WO2023099793A1

WO2023099793A1 - Novel compositions comprising retinoids

Info

Publication number: WO2023099793A1
Application number: PCT/EP2022/084471
Authority: WO
Inventors: Christine Mendrok-Edinger; Eileen JACKSON; Angela Wildermann; Peter Louis HOUSTON
Original assignee: Dsm Ip Assets B.V.
Priority date: 2021-12-03
Filing date: 2022-12-05
Publication date: 2023-06-08

Abstract

The present invention relates to novel compositions comprising a retinoid mixture of cis and trans isomers of retinoids, particularly with a cis/trans ratio of less than 0.01 (1:100) as well as the use thereof for the prevention and/or treatment of adverse skin conditions associated with an imbalanced skin microbiome, particularly for prevention or treatment or lessening of ailments associated with Cutibacterium acnes, Corynebacterium xerosis and/or Matassezia, particularly Matassezia furfur.

Description

NOVEL COMPOSITIONS COMPRISING RETINOIDS

The normal skin flora consists of a variety of commensal skin microbes which live in homeostasis or balance with the host. To protect against potentially pathogenic microbes and/or imbalance of the commensal skin microbes, antimicrobial active compounds play a key role for many cosmetic applications, including but not limited to prevention/treatment/lessening of symptoms of acne or malodor caused by sweating.

Acne is taken to mean a skin disorder which is evident in inflamed papules, pustules or nodules, caused by increased talc production and impaired keratinization of the skin. The inflammation may be associated with reddening, swelling and pressure pain. Besides genetic predisposition, possible causes of acne formation can be androgens, comedogenic substances (for example in cosmetics), smoking, stress or excessive colonization of the skin by bacteria. Acne is in particular triggered by the microorganism Cutibacterium acnes, which is a bacterium which normally colonizes the skin and lives on sebum. Acne may arise, for example, if the number of these bacteria is increased. The presence of bacteria in the follicles results in inflammation reactions, which is evident in the form of red nodules or pustules. The production of free fatty acids by the bacteria furthermore promotes the inflammation reaction in the follicle. One approach to acne treatment is the use of systemic or topical agents comprising antimicrobial active compounds which address the overgrowth of Cutibacterium acnes.

The fungal genus Matassezia comprises lipid-dependent and lipophilic yeast species that are part of the normal skin microbiota. In general, because of their dependence on lipids for survival, Matassezia yeasts are most often found in sebum-rich areas of the skin such as the trunk, back, face, and scalp. Several adverse skin conditions have been associated with an overpopulation of Matassezia yeasts, in particular Matassezia furfur (M. furfur), such as itching skin, pityriasis versicolor, dandruff formation, seborrheic dermatitis atopic dermatitis, and psoriasis. Again, one effective approach to treat adverse effects associated with M. furfur is to topically apply anti-fungal agents.

Besides water and salt, axillary sweat contains many other substances (such as fats, amino acids, sugars, lactic acid, urea, etc.). Freshly formed sweat is odorless; the typical sweat odor only forms due to the action of skin bacteria on the sweat, which decompose the latter. Examples of such bacteria are Corynebacterium such as Corynebacterium xerosis. For this reason, antimicrobial substances are usually also employed besides aroma substances and antiperspirants in deodorants, with the aim of controlling the bacteria which are involved in the odor formation.

Thus, there is an ongoing need for mild treatments for the reduction of one or more of the above-mentioned microbes on the skin of humans and animals, i.e. treatments which are well tolerated by the skin, to maintain a healthy homeostasis of the skin and/or improve the health of the skin microbiome and thus to alleviate potential negative ailments associated with said microbes.

Surprisingly it has now been found that certain retinoid mixtures of cis/trans isomers, particularly with a cis/trans ratio of less than 0.01, are capable of improving the homeostasis of the skin microbiome, i.e. exhibit an excellent antimicrobial activity against Cutibacterium acnes, Corynebacterium xerosis and/or Matassezia, particularly M. furfur, and are thus particularly suitable for mitigating or treating adverse effects resulting from an overpopulation thereof, such as particularly useful for prevention, treatment and/or lessening the symptoms of acne, itching or malodor caused by sweat.

Thus, the present invention relates to a retinoid mixture comprising cis- and trans-isomers of retinoids comprising retinol, retinal, retinyl acetate, retinoic acid, with a cis/trans ratio of less than 0.01, particularly retinoid mixtures comprising retinol and retinyl acetate wherein the cis/trans ratio is in the range of from 0.0049 to 0.0025. Particularly, the present invention relates to pharmaceutical, food, feed or cosmetic composition comprising said retinoid mixture comprising cis and trans isomers, with a cis/trans ratio of less than 0.01.

The term "retinoid" as used herein refers to compounds of formula (l) (without any indication of the stereochemistry):

formula (l), wherein

R is -CHO, -CH₂OH, -COOH, -CH(R¹)₂, -CH₂OR², -COOR³, -C0NHR⁴, or -CO(NR⁴)₂, R1 are independently lower alkoxy or R¹' and R¹" taken together are lower alkylenedi oxy,

R² is alkanoyl or aroyl,

R³ is alkyl, aryl or aralkyl; and

R⁴, R⁴' and R⁴’’ are independently hydrogen, alkyl, aryl or aralkyl; wherein the term "lower alkoxy" is an alkoxy group with 1 to 6 carbon atoms, such as, for example, methoxy, ethoxy or propoxy; the term "lower alkylenedioxy" is such a group which likewise contains 1 to 6 carbon atoms, e.g., methylenedioxy or ethylenedioxy and wherein the alkyl or alkylene part can be straight-chain or branched depending on the number of carbon atoms; the term "alkanoyl" refers to either straight-chain or branched alkanoyl groups with 1 to18 carbon atoms, such as, for example, formyl, acetyl, propionyl, butyryl, stearoyl and palmitoyl; the term "aroyl" refers to aromatic carboxylic acids with 7 and 11 carbon atoms, including benzoyl or naphthoyl, respectively; the term "alkyl" is a straight-chain or branched alkyl group with 1 to 18 carbon atoms, e.g., methyl, ethyl, propyl, butyl, decyl, dodecyl, hexadecyl or octadecyl; the term "aryl" as such or as part of "aralkyl" is phenyl or naphthyl; and the term "aralkyl" embraces such groups with 1 to 4 carbon atoms in the aliphatic part, e.g., benzyl and phenylpropyl.

Particularly, compounds according to formula (l) as defined herein are selected from vitamin A and/or derivatives thereof including but not limited to one or more retinoids selected from retinol, retinal, retinoic acid, as well as derivatives such as esters, acetals and/or amides, particularly esters, more particularly retinyl acetate. Particularly suitable retinyl esters according to the present invention are retinyl acetate, retinyl propionate, retinyl linoleate, retinyl palmitate, retinyl retinoate and/or retinyl formyl aspartamate. Preferably, the compounds according to formula (l) are selected from retinol and/or retinyl esters, particularly retinol and/or retinyl acetate.

Preferred in all embodiments of the present invention is the use of retinol and/or its esters, particularly retinol and/or retinyl acetate, as antimicrobial agent with a cis/trans ratio as defined herein. In all embodiments, retinyl acetate is furthermore particularly suitable as anti-microbial agent against Cutibacterium acnes, Corynebacterium xerosis and Malassezia, preferably M. furfur, while retinol is particularly suitable as antimicrobial agent against Cutibacterium acnes.

The cis/trans ratio as given herein refers to the wt.-% ratio of the sum of all cis- isomers to the respective all trans isomer of the respective retinoid, such as e.g. retinyl acetate, retinol, retinal or the like, as determined by known methods such as e.g. HPLC, assuming the same response factor for all isomers.

As used herein, a "retinoid mixture" comprises retinyl ester isomers, particularly retinyl acetate isomers, such as cis- and trans-isomers, in a ratio as defined herein. The retinoid mixture might comprise cis and/or trans isomers of retinol or retinal.

As used herein, the cis/trans ratio, particularly the ratio of cis-isomers to trans- isomers in a retinoid mixture comprising retinyl acetate, retinol or retinal, more particularly the ratio of cis-retinyl acetate to trans-retinyl acetate or the ratio of cis-retinol to trans-retinol or the ratio of cis-retinal to trans-retinal, means comparing the wt% of a cis-isomer to the wt% of the corresponding trans- isomer, all based on total retinoids in said mixture. Thus, a mixture comprising a cis/trans ratio of 0.03 with regards to retinyl acetate is a mixture with e.g. 1 wt% cis-retinyl acetate based on total retinoids within said mixture and 33 wt% trans-retinyl acetate based on total retinoids within said mixture. A cis/trans ratio of 0.03 with regards to retinyl acetate would also apply to a mixture with 2.95 wt% cis-retinyl acetate and 94.15% trans-retinyl acetate, or with 2.99 wt% cis-retinyl acetate and 99.6% trans-retinyl acetate, or with 2.98 wt% cis-retinyl acetate and 99.2 wt% trans-retinyl acetate, or with 2.97 wt% cis-retinyl acetate and 99.7 wt% trans-retinyl.

As used herein, the term "trans-retinyl acetate", "trans-retinol", "trans-retinal" or the like are known to the skilled person and in line with the IUPAC-IUB nomenclature and mean that all double bonds in such retinyl acetate, retinol, retinal compound, including the compound according to formula (l), are in trans configuration. The term "trans-retinyl ester", particularly "trans-retinyl acetate", and "all-trans-retinyl ester", particularly "all-trans-retinyl acetate", are used interchangebly herein. Thus, if one of several double bonds is not in the trans configuration but in the cis configuration, such isoforms are named herein as e.g. cis-retinyl acetate or cis-retinol or cis-retinal.

Retinoid isomers in cis-configuration that are covered by the present invention include but are not limited to 9-cis-retinol, 11 -cis retinol, 13-cis retinol, 9, 13-d i- cis-retinol, 11,13-di-cis retinol, 13-cis-3,4-didehydro retinol, 9-cis-3,4-didehydro retinol, 9,13-di-cis-3,4-didehydro retinol, 13-cis retinal, 11-cis-retinal, 11,13-di-cis retinal, 9, 13-d i-cis-reti nal, 9-cis retinal, 13-cis-3,4-didehydro retinal, 11,13-di-cis- 3,4-didehydro retinal, as well as the respecitve cis-forms of retinyl acetate (for review, see e.g. Table 1 in Gundersen and Blomhoff, J. Chromatogr. A 935, 13-43, 2001).

In all embodiments of the present invention, the cis/trans ratio of retinoid isomers as defined above, i.e. wt% of cis- or trans-isomers of retinoids such as e.g. retinyl ester, particularly retinyl acetate, retinol, retinal based on total retinoids in the mixture, is less than 0.01, preferably a cis/trans ratio of 0.0099, 0.0095, 0.009, 0.0085, 0.008, 0.0075, 0.007, 0.0065, 0.006, 0.0055, 0.005, 0.0049, 0.0045, 0.0043, 0.004, 0.0035, 0.003, 0.0028, 0.0025, 0.0022, 0.002, 0.0018, 0.0015, 0.001, 0.0005 or less, such as 0.0001 or less, more preferably ranges of 0.0099 to 0.0001, 0.008 to 0.001, 0.007 to 0.002, 0.0099 to 0.001, 0.005 to 0.001, 0.005 to 0.0001, 0.005 to 0.0005, 0.006 to 0.001, 0.009 to 0.0001, 0.008 to 0.0001, 0.006 to 0.0001, 0.0055 to 0.0001, 0.005 to 0.002, 0.007 to 0.0001, 0.0045 to 0.0001, 0.004 to 0.0001, 0.0035 to 0.0001, 0.003 to 0.0001, 0.005 to 0.0025, 0.004 to 0.0005, 0.006 to 0.0005, 0.006 to 0.0008, 0.006 to 0.0015, 0.006 to 0.002, 0.006 to 0.003, 0.006 to 0.0004, 0.006 to 0.0025, most preferably a cis/trans ratio of 0.0049 to 0.0025. According to further inventive embodiments, the cis/trans ratio of retinol isomers as defined above, i.e. wt% of cis- or trans-retinol, based on total retinoids in the mixture, is 1:more than 100, preferably a cis/trans ratio of 1:105, 1:105.26, 1:110, 1:111.11, 1:117.65, 1:120, 1:125, 1:130, 1:133.33, 1:135, 1:140, 1:142.86, 1:150, 1:153.85, 1:155, 1:160, 1:165, 1:166.67, 1:170, 1:175, 1:180, 1:181.82, 1:185, 1:190, 1:195, 1:200, 1:204.08, 1:205, 1:210, 1:215, 1:220, 1:222.22, 1:225, 1:230, 1:232.56, 1:235, 1:240, 1:245, 1:250, 1:255, 1:260, 1:265, 1:270, 1:275, 1:280, 1:285, 1:285.71, 1:290, 1:300, 1:305, 1:310, 1:320, 1:325, 1:330, 1:333.33, 1:340, 1:345, 1:350, 1:357.14, 1:360, 1:370, 1:380, 1:390, 1:400, 1:420, 1:450, 1:454.55, 1:460, 1:480, 1:500, 1:520, 1:550, 1:555.56, 1:600, 1:666.67, 1:700, 1:800, 1:900, 1:1000, 1:1200, 1:1500, 1:2000, 1:2500, 1:2800, 1:4000, 1:5000, 1:7000 or less, such as 1:1000 or less, more preferably ranges of 1:101 to 1:10000, 1:125 to 1:1000, 1:140 to 1:500, 1:101 to 1:1000, 1:200 to 1:1000, 1:200 to 1:10000, 1:200 to 1:2000, 1:600 to 1:1000, 1:110 to 1:10000, 1:500 to 1:700, 1:150 to 1:400, 1:200 to 1:500, 1:250 to 1:400, 1:250 to 1:1000, most preferably a cis/trans ratio of 1:100 to 1:500, even more preferably 1:200 to 1:400.

In one preferred embodiment, the retinoid according to formula (l) is retinyl acetate, thus, a retinoid mixture comprising retinyl acetate particularly with a cis/trans ratio of less than 0.01, preferably 0.0099, 0.0095, 0.009, 0.0085, 0.008, 0.0075, 0.007, 0.0065, 0.006, 0.0055, 0.005, 0.0049, 0.0045, 0.0043, 0.004, 0.0035, 0.003, 0.0028, 0.0025, 0.0022, 0.002, 0.0018, 0.0015, 0.001, 0.0005 or less, such as 0.0001 or less, more preferably ranges of 0.0099 to 0.0001, 0.008 to 0.001, 0.007 to 0.002, 0.009 to 0.0001, 0.008 to 0.0001, 0.005 to 0.001, 0.005 to 0.0001, 0.005 to 0.0005, 0.006 to 0.001, 0.006 to 0.0001, 0.0055 to 0.0001, 0.007 to 0.0001, 0.0045 to 0.0001, 0.005 to 0.002, 0.004 to 0.0001, 0.0035 to 0.0001, 0.003 to 0.0001, 0.005 to 0.0025, 0.006 to 0.0005, 0.006 to 0.0008, 0.006 to 0.0015, 0.006 to 0.002, 0.006 to 0.003, 0.006 to 0.0004, 0.006 to 0.0025, 0.004 to 0.0005, most preferably a cis/trans ratio of 0.0049 to 0.0025. Compositions, particularly pharmaceutical, food, feed or cosmetic compositions comprising retinoid mixtures as defined herein comprising retinyl acetate with a cis/trans ratio as above are particularly useful for prevention, treatment or lessening the symptoms of acne, itching skin, pityriasis versicolor, dandruff formation, seborrheic dermatitis atopic dermatitis, psoriasis and/or malodor caused by sweat, particularly useful as antimicrobial agents against Cutibacterium acnes, Corynebacterium xerosis and/or Malassezia, preferably M. furfur.

In one preferred embodiment, the retinoid according to formula (l) is retinol, thus, a retinoid mixture comprising retinol particularly with a cis/trans ratio of less particularly with a cis/trans ratio of less than 0.01, preferably a cis/trans ratio Of 0.0099, 0.0095, 0.009, 0.0085, 0.008, 0.0075, 0.007, 0.0065, 0.006, 0.0055, 0.005, 0.0049, 0.0045, 0.0043, 0.004, 0.0035, 0.003, 0.0028, 0.0025, 0.0022, 0.002, 0.0018, 0.0015, 0.001, 0.0005 or less, such as 0.0001 or less, more preferably ranges of 0.0099 to 0.0001, 0.008 to 0.001, 0.007 to 0.002, 0.0099 to 0.001, 0.005 to 0.001, 0.005 to 0.0001, 0.005 to 0.0005, 0.006 to 0.001, 0.009 to 0.0001, 0.008 to 0.0001, 0.006 to 0.0001, 0.0055 to 0.0001, 0.005 to 0.002, 0.007 to 0.0001, 0.0045 to 0.0001, 0.004 to 0.0001, 0.0035 to 0.0001, 0.003 to 0.0001, 0.005 to 0.0025, 0.004 to 0.0005, 0.006 to 0.0005, 0.006 to 0.0008, 0.006 to 0.0015, 0.006 to 0.002, 0.006 to 0.003, 0.006 to 0.0004, 0.006 to 0.0025, most preferably a cis/trans ratio of 0.003. Compositions, particularly pharmaceutical, food, feed or cosmetic compositions comprising retinoid mixtures as defined herein comprising retinol with a cis/trans ratio as above are particularly useful for prevention, treatment and/or lessening the symptoms of acne, particularly useful as antimicrobial agents against Cutibacterium acnes.

The retinoid mixture comprising cis and trans isomers of retinoids according to formula (l), particularly retinyl esters, preferably retinyl acetate, and/or retinol according to the present invention can either be prepared by admixing the respective all trans isomers with one or more cis isomers obtained by chemical or biological processes. Methods to prepare such all trans and/or cis isomers are well known to a person skilled in the art. Alternatively, the mixture can be prepared in said isomer ratio by adjusting the processes accordingly.

Advantageously, in all embodiments of the present invention, the retinoid mixtures comprising retinoids as of formula (l) and as defined herein, are biologically produced through a fermentation process. In this process trans retinyl esters, in particular trans retinyl acetate, and/or retinol are made through the action of specific enzymes that results in stable all trans retinyl esters, preferably all trans retinyl acetate, being produced. The trans retinyl ester, preferably trans retinyl acetate, can be treated with heat to form cis retinyl esters, preferably cis retinyl acetate, to achieve the proper levels mentioned previously in all the embodiments of the present invention (see e.g. McBee et al., JBC, Vol. 276, No. 51, pp. 48483-48493, 2001).

Advantageously, in all embodiments of the present invention, the retinoid mixtures comprising cis and trans retinoids as defined herein including retinol and retinyl esters, particularly retinyl acetate, with a cis/trans ratio of less than 0.01, particularly wherein the cis/trans ratio is in the range of from 0.0049 to 0.0025, preferably wherein said retinoids as defined herein are biologically produced through a fermentation process, preferably leading to a retinoid mixture with yellowish color.

As known in the art, color can be precisely described in several different co- ordinate systems, such as XYZ, RGB, CYMK, or L*a*b* (CIELAB according to EN ISO/CIE 11664-4: 2019). A preferred method is the definition via the L*a*b* system. The skilled person knows which instrument to use depending on the different color measurement systems and how to measure the color of the mixtures as described herein.

A "yellowish" color as used herein means a color as defined by the L*a*b* color system, particularly wherein L*a*b* being (3<L*<100, -25<a*<30,10<b*<150), such as e.g. L* being in the range of 50 to 100, a* being in the range of -25 to 10 and b* being in the range of 40 to 150, preferably wherein L* being in the range of 80 to 100, a* being in the range of -22 to 1, b* being in the range of 40 to 85 or 100 to 140, more preferably L* being in the range of 80 to 95, a* being in the range of - 17 to -1, b* being in the range of 105 to 135, particularly L* being about 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100 and a* being about -24.9, -24, -23, -22, -21, -20, -19, -18, -17, -18, -17, -16, -15, -14, -13, -12, -11, - 10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0 and b* being about 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135.

In a particular embodiment, the retinoid mixture comprising cis and trans isomers of retinoids as defined herein, particularly retinyl esters, preferably retinyl acetate, and/or retinol are produced in a fermentation process using suitable retinol producing host cells, such as e.g. bacterial or fungal cells, (see e.g. Sun et al, ACS Synth. Biol. 2019 Sep 20;8(9):2131 -2140; Jang et al., Microbial Cell Factories 2011, 10:59), wherein the cells are expressing the respective enzymes, such as e.g. trans-selective enzymes, i.e. beta-carotene oxidase (BCOs) involved in biosynthesis of retinol from conversion of beta-carotene into retinal, that might be further enzymatically converted into retinol and/or retinyl esters, particularly retinyl acetate. Particularly, the fermentation is fed ethanol, corn sugar or corn oil all derived from agricultural production. The fermentation products comprising retinyl esters, particularly retinyl acetate, and/or retinol might be extracted in an aliphatic phase and subsequently purified to crystalline forms by methods as used in the art. In some embodiments, mixtures of retinoids as defined herein, particularly mixtures comprising retinyl acetate and retinol with specific cis/trans ratio according to the present invention are obtained in a fermentation process with retinoid-producing host cells, wherein beta-carotene is enzymatically converted into retinoids comprising retinal, retinol or retinyl acetate with a cis/trans ratio as defined herein, wherein the inventive cis-/trans ratio can be obtained using one or more enzymes having oxygenase and isomerase functionality (see e.g. Oberhauser et al., PNAS, vol 105, no. 48, 19003, 2008). Particularly, the retinoid- producing host organism is capable of enzymatically converting beta-carotene into retinyl acetate via retinal and retinol.

The term "biologically produced" as used herein means that the retinoids, particularly retinyl esters, particularly retinyl acetate, and/or retinol is produced by the help of biotechnological process, such as a fermentation process including cultivation of a suitable (carotenoid and/or retinoid producing) host cell expressing the respective enzymes involved in conversion of a suitable carbon source into retinyl esters, particularly retinyl acetate, and/or retinol as defined herein, wherein the host cell might be selected from bacteria, fungi, particularly yeast, plant or algae, particularly from fungal cells, such as e.g. Yarrowia or Saccharomyces, or bacterial cells, such as e.g. E. coli. It might furthermore be selected from other suitable microorganism known to produce retinoids. "Bio-produced", "biologically-derived" and "biologically produced" or "bio-based" are used synonymously herein. Accordingly, said biologically produced retinoids according to formula (l) are composed of carbon from atmospheric carbon dioxide (also referred to as carbon of atmospheric origin) converted to sugars and starches by green plants and thus preferably sugars and starches composed of non-fossil-fuel carbon. It also includes the use of isolated and/or immobilized enzymes in a process for generation of the retinoid mixtures as defined herein, such as specific enzymes capable of selectively catalyzing the formation of the specific trans/cis ratio of retinoids, particularly retinyl esters, preferably retinyl acetate, and/or retinol in a mixture as defined herein.

In one aspect, the retinoid mixture as defined herein is produced via fermentation using a fungal host cell, such as e.g. an oleaginous yeast, particularly Yarrowia, said host cell being cultivated in the presence of a suitable carbon source and in the presence of a plant-based second phase, e.g. vegetable oil, such as e.g. corn oil, as second phase solvent, wherein the retinoids are accumulated in the second phase.

Suitable plant-based second phase solvents might be selected from any vegetable oil, including but not limited to oleic, palmitic, steric or linoleic acid and glycerol, such as e.g. corn, olive, cottonseed, rapeseed, sesame, canola, safflower, sunflower, soybean, grapeseed, or peanut oil, preferably corn oil.

Carbon sources to be used for the present invention might be selected from linear alkanes, free fatty acids, ethanol, glucose and/or mixtures thereof.

As used herein, a "bio-based" compound has a C-14/C-12 isotope ratio in the range of from 1:0 to greater than 0:1, as in contrast to a fossil-based compound with a C-14/C-12 isotope ratio of 0:1. Bio-based content of a compound can be measured by known radiocarbon and isotope ratio mass spectrometry analysis or accelerator mass spectrometry, such as e.g. the ASTM test method D6866 such as D6866-05 or D6866-20, DIN SPEC 91236 (CEN/TS 16137), ISO 16620, or DIN EN 16785/1, wherein the C-14/C-12 isotope ratio in a sample is measured and compared to a standard 100% biobased material to give percent biobased content of the sample.

"Carbon of atmospheric origin" as used herein refers to carbon atoms from carbon dioxide molecules that have recently, in the last few decades, been free in the earth's atmosphere. Such carbons in mass are identifiable by the presence of particular radioisotopes as described herein. "Green carbon", "atmospheric carbon", "environmentally friendly carbon", "life-cycle carbon", "non-fossil fuel- based carbon", "non-petroleum based carbon", "carbon of atmospheric origin", and "biobased carbon" are used interchangeably herein.

In all embodiments of the present invention, advantageously the mixtures comprising retinoid according to formula (l) comprising retinol and/or retinyl esters, preferably retinyl acetate, are produced by merely organic, renewable, bio-based feedstock, particularly fermentatively produced, as such retinol and/or retinyl esters, preferably retinyl acetate, has an anthropogenic CO₂ emission profile of zero upon biodegradation because all of the CO₂ molecules released during degradation from such "fermentatively-derived" or "fermentatively-produced" retinoids have an atmospheric origin. Thus, the net release of CO₂ to the atmosphere is zero.

Thus, the present invention is particularly directed to a retinoid mixture comprising retinyl acetate and retinol comprising cis- and trans-isomers as defined herein, with a cis-/trans ratio (defined as wt% based on total retinoids in the mixture) of less than 0.01, wherein said mixture has at least about 20%, such as 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 98 or 100% biobased carbon according to the definition given in the present application.

Particularly, the present invention is directed to a biodegradable composition comprising a mixture of retinyl acetate with a cis-/trans-ratio of less than 0.01 as defined herein, wherein the retinyl acetate mixture in said composition has an anthropogenic CO₂ emission profile of zero upon biodegradation.

In a further embodiment, the present invention relates to the use of said retinoid mixture and/or pharmaceutical, food, feed or cosmetic composition comprising said mixture of cis and trans isomers of retinoids, particularly retinyl acetate and/or retinol, as defined herein as antimicrobial agent, i.e. an agent which exhibits an antimicrobial activity particularly on the skin. In particular, the present invention is directed to the use of a retinoid mixture and/or pharmaceutical, food, feed or cosmetic composition comprising said mixture according to the present invention as antimicrobial agent, more particularly as an agent for inhibiting (reducing) and/or abolishing the growth of skin microbes such as in particular selected from Cutibacterium acnes, Corynebacterium xerosis and/or Malassezia, such as in particular M. furfur.

In another embodiment, the invention relates to a method or process for inhibiting and/or abolishing growth of microbial cells growing on the skin, in particular cells of Cutibacterium acnes, Corynebacterium xerosis and/or Malassezia, preferably M. furfur, said method comprising contacting said microbial cells with a retinoid mixture and/or pharmaceutical, food, feed or cosmetic composition comprising said mixture according to the present invention.

In all embodiments of the present invention and as used herein, the term "antimicrobial activity" or "antimicrobial effect" preferably refers to the capability of inhibiting and/or abolishing the growth of skin microbes, particularly cells of Cutibacterium acnes, Corynebacterium xerosis and/or Malassezia, preferably M. furfur, in a given sample or in a human or animal in need thereof and compared to the inoculum respectively a control as outlined in the examples. The terms "abolishing" and "killing" are used interchangeably herein. The term "growth" in connection with skin microbes and as used herein refers to unwanted or unhealthy growth of the microbes as defined herein, resulting to an increase of microbial cells on the skin compared to a balanced and healthy skin microbiome.

Due to the antimicrobial activity against skin microbes such as Cutibacterium acnes, Corynebacterium xerosis and/or Malassezia, particularly M. furfur, the retinoid mixtures and/or pharmaceutical, food, feed or cosmetic compositions comprising said mixtures according to the present invention are further suitable for the treatment, prevention and/or lessening the symptoms of adverse skin conditions associated with an overpopulation of said microbes, such as acne control application (Cutibacterium acnes), deodorant applications (Corynebacterium xerosis) and hair care such as in particular dandruff applications (Malassezia, preferably M. furfur).

For example, the above-mentioned antimicrobial effect can be used for microbiome balancing, e.g., when applied on an external surface of the human or animal body.

Thus, in another embodiment, the retinoid mixtures and/or pharmaceutical, food, feed or cosmetic compositions comprising said mixtures as defined herein are in particularly useful as antimicrobial compounds in cosmetic or pharmaceutical products used for controlling/ reducing acne, particularly used to inhibit overpopulation of Cutibacterium acnes on the skin, as components of deodorants, particularly used to inhibit overpopulation of Corynebacterium xerosis causing malodor upon sweating, or for controlling/ reducing dandruff, particularly used to inhibit overproduction of Malassezia, preferably M. furfur.

Said antimicrobial effect can, however, also be used to prevent and/or treat diseases linked with a dysbiosis or imbalance of skin microbiota associated with an increased number (or overpopulation)/growth of Cutibacterium acnes, Corynebacterium xerosis and/or Malassezia, particularly M. furfur.

Thus, the present invention furthermore relates to the use of a retinoid mixture and/or pharmaceutical, food, feed or cosmetic composition comprising said mixture of the present invention as anti-acne, deodorant or anti-dandruff active compound, as well cosmetic or pharmaceutical products, such as anti-acne, anti-dandruff and/or deodorants comprising the retinoid mixtures and/or pharmaceutical, food, feed or cosmetic compositions comprising said mixtures as defined herein as active compounds, wherein particularly a retinoid mixture comprising retinyl acetate and retinol with a cis/trans ratio as defined herein is suitable for the treatment, prophylaxis and/or lessening the symptoms of acne, wherein particularly a retinoid mixture comprising retinyl acetate with a cis/trans ratio as defined herein is suitable as deodorant compound by reducing/inhibiting the formation of malodor and for the treatment, prophylaxis and/or lessening the symptoms of dandruff.

"Prevention" or "prophylaxis" as used herein includes not only total prevention, delaying the onset of, lessening the severity of symptoms of the condition, and/or increasing the length of time between recurrence of the condition.

Thus, it is well understood, that retinoid mixtures and/or the pharmaceutical, food, feed or cosmetic composition comprising said mixtures comprising cis and trans isomers of retinoids according to formula (l) and as defined herein, particularly retinoids selected from retinyl esters, preferably retinyl acetate, and/or retinol having a cis/trans ratio of less than 0.01 according to the present invention can be used both in the cosmetic sense as well as in the pharmaceutical sense.

A pharmaceutical application is conceivable, for example, for the treatment, prevention and/or lessening of any disorder and disease associated with said microbes such as in particular Cutibacterium acnes and/or Malassezia, preferably M. furfur, in a human (e.g. a patient) or animal in need thereof such as in the treatment, prevention and/or lessening of the symptoms of pityriasis versicolor, dandruff formation, seborrheic dermatitis, atopic dermatitis, psoriasis and acne.

A cosmetical application is conceivable, if the application is intended to preserve and/or enhance the beauty and/or youthfulness of a person specifically as it relates to the appearance of tissue or skin. Preferred cosmetic (non-therapeutic) applications according to the present invention encompass the treatment, prevention and/or lessening the symptoms of itching skin, the maintenance of skin homeostasis, the provision of microbiome balancing as well as the reduction of malodor formation caused by sweat.

In one preferred embodiment the retinoid mixture according to the present invention consists essentially of cis- and trans-retinoids according to formula (l), such as retinol and/or retinyl ester, particularly retinyl acetate, in the ranges and with all the definitions and preferences as given herein.

The term "consists essentially of" as used according to the present invention means that the total amount of ingredients within the mixture ideally sum up to 100 wt.-%. It is however not excluded that small amounts of impurities or additives may be present in the mixture, with the proviso that the total amount of such impurities is preferably less than about 5 wt.-%, more preferably less than about 3, 2, 1 wt.-% and which are e.g. introduced via the respective raw materials and/or processes used.

As used herein, the term "impurities" and "additives" are used interchangeably herein and refer to co-ingredients within the inventive mixture and that are present in the inventive mixture in an amount of less than 5 wt.-% based on all ingredients present in the mixture.

If the retinoid mixture according to the present invention consists essentially of retinyl acetate with a cis/trans ratio as defined herein, then the purity of said mixture, i.e. the (total) amount of cis and trans retinyl acetate is preferably at least about 95%, more preferably at least about 96%, most preferably at least about 98% or more, as determined by methods known in the art, such as e.g. HPLC, particularly reversed phase C4 HPLC.

If the mixture and/or composition comprising said mixture according to the present invention consists essentially of retinol, then the purity of said mixture, i.e. the (total) amount of cis and trans retinol is preferably at least about 95%, more preferably at least about 96%, most preferably at least about 98% or more, as determined by methods known in the art, such as e.g. HPLC, particularly reversed phase C4 HPLC.

As used herein, the term "purity" means the sum of cis- and trans isomers in relation to the total weight, e.g. the sum of cis-retinyl acetate and trans-retinyl acetate according to the definition given herein gives a percentage of purity based on total retinoids set to 100% purity. Thus, if a mixture consists essentially of 98.03 wt% trans-retinol and 0.25 wt% cis-retinol, said mixture has a purity with regards to retinol of 98.28%. Preferably, and in accordance with all embodiments of the present invention, the retinoid mixture comprises less than 0.5 wt% cis-retinyl esters, particularly cis-retinyl acetate, based on total retinoids in said mixture. Preferably, and in accordance with all embodiments of the present invention, the retinoid mixture comprises comprises less than 0.3 wt% cis-retinol based on total retinoids in said mixture.

In one embodiment, the retinoid mixtures comprising cis and trans retinoid isomers, particularly retinyl acetate and/or retinol with a cis/trans ratio as defined herein further comprise small amounts of additives such as e.g. dihydro- retinoids, including dihydro-retinol and/or di hydro- retinyl acetate, particularly in a range of 0.2 to 0.01 wt% or less, such as e.g. 0.2, 0.18, 0.16, 0.15, 0.14, 0.12, 0.1, 0.05, 0.01 wt% or less, preferably a range of 0.2 to 0.1, 0.17 to 0.06, 0.1 to 0.05, 0.04 to 0.01 wt%, more preferably a percentage of 0.1 wt% or less, all based on total retinoids within said mixture. Also preferably, the percentage of dihydro- retinyl acetate is about 0.05 wt% or less, particularly about 0.01 wt% or less based on total retinoids within said mixture.

In some embodiments, the retinoid mixtures comprising cis and trans retinyl acetate and retinol with a cis/trans ratio as defined herein further comprise small amounts of additives such as e.g. retinal, including but not limited to 9-cis retinal, trans retinal, such as in amounts of 1 wt% or less, such as about 0.8, 0.7, 0.5, 0.2, 0.1, 0.08, 0.05, 0.03, 0.02, 0.01, 0.005 wt% or less, preferably percentage of retinal in the range of 1 to 0.005 wt%, 0.5 to 0.01 wt%, 0.5 to 0.02 wt%, 0.05 to 0.01 wt%, 0.05 to 0.02 wt%, 0.04 to 0.1 wt%, 0-2 to 0.04 wt%, most preferably a range of 0.2 to 0.019 wt% or 0.04 to 0.01 wt% all based on total retinoids within said mixture.

To make use of the antimicrobial activity against Cutibacterium acnes, Corynebacterium xerosis and/or Malassezia, preferably M. furfur, of the retinoid mixtures and/or pharmaceutical, food, feed or cosmetic compositions comprising said mixtures according to the present invention, they can be used in a multiplicity of applications, such as, for example, cosmetic or pharmaceutical products.

Thus, in another embodiment, the compositions according to the present invention are cosmetic or pharmaceutical products further comprising a cosmetically or pharmaceutically acceptable carrier.

The term "cosmetically or "pharmaceutically acceptable carrier" refers to all carriers and/or excipients and/or diluents conventionally used in cosmetic compositions or pharmaceutical products. As used herein, it can be understood to be a physiologically acceptable medium, i.e. a medium compatible for the intended use such as e.g. with keratinous substances, such as the skin, mucous membranes, and keratinous fibers.

The term "cosmetic product" as used in the present application refers to compositions as defined under the heading "Kosmetika" in Rompp Lexikon Chemie, 10th edition 1997, Georg Thieme Verlag Stuttgart, New York as well as to cosmetic compositions as disclosed in A. Domsch, "Cosmetic Compositions", Verlag fur chemische Industrie (ed. H. Ziolkowsky), 4^th edition, 1992 and refers to products/ compositions which are used to treat, care for or improve the appearance of the skin and/or scalp.

The term "pharmaceutical composition" or "pharmaceutical products" as used herein refers to compositions which are used for the treatment, prevention and/or lessening of the symptoms of diseases and/or disorders.

Preferably the cosmetic or pharmaceutical products according to the present invention comprise the retinoid mixture comprising cis and trans isomers of retinoids according to formula (l) or pharmaceutical, food, feed or cosmetic compositions comprising such mixtures with all the definitions and preferences as given herein in an amount from 0.00001 to 1 wt.-%, more preferably from 0.0001 to 0.75 wt.-%, most preferably from 0.001 to 0.5 wt.-%, based on the total weight of the composition. Further particular suitable ranges include 0.01 to 0.2 wt.-% or 0.05 to 0.2 wt.-%.

Further advantageous according to the present invention is the use of a retinoid mixture or pharmaceutical, food, feed or cosmetic composition comprising said mixture with all the definitions and preferences as given herein as active compound in deodorants or antiperspirants as it has an antimicrobial action against Corynebacterium xerosis which is responsible for the decomposition of sweat and thus for the formation of the malodor, even at very low concentrations of less than 0.15 wt.-%.

Thus, in another advantageous embodiment the cosmetic or pharmaceutical product according to the present invention are deodorant compositions comprising a retinoids, such as particularly retinyl acetate and/or retinol, with a cis/trans ratio as defined herein in an amount of 0.01 to 0.15 wt.-%, preferably of 0.05 to 0.15 wt.-%, based on the total weight of the composition as these compositions are particularly suitable to avoid the unpleasant odor formation caused by or Corynebacterium xerosis by killing respectively significantly inhibiting the growth of these specific bacteria selectively at this concentration range.

Also advantageous according to the present invention is the use of a retinoid mixture and/or pharmaceutical, food, feed or cosmetic compositions comprising said mixtures with all the definitions and preferences as given herein as active compound in anti-acne preparations as it has an antimicrobial action against Cutibacterium acnes, even at very low concentrations of less than 0.3 wt.-% or even less than 0.15 wt.-%. Thus, in another advantageous embodiment the cosmetic or pharmaceutical products according to the present invention are anti-acne products comprising retinoids, particularly retinyl acetate and/or retinol as defined herein in an amount of 0.01 to 0.3 wt.-%, preferably of 0.05 to 0.25 wt.-%, based on the total weight of the product as these compositions are particularly suitable to kill respectively significantly inhibit the growth of Cutibacterium acnes. Particularly suitable anti-acne compositions are creams, lotions and the like, preferably in the form of an emulsion such as an O/W emulsion as disclosed herein.

Also advantageous according to the present invention is the use of a retinoid mixture and/or pharmaceutical, food, feed or cosmetic composition comprising said mixture with all the definitions and preferences as given herein as active compound in anti-dandruff preparations as it has an antimicrobial action against Matassezia, preferably M. furfur, even at very low concentrations of less than about 0.3 wt.-%.

Thus, in another advantageous embodiment the cosmetic or pharmaceutical products according to the present invention are anti-dandruff compositions comprising said retinoid mixtures or pharmaceutical, food, feed or cosmetic compositions comprising said mixtures, in an amount of 0.1 to 0.3 wt.-%, based on the total weight of the product as these products are particularly suitable to kill respectively significantly inhibit the growth of Matassezia, preferably M. furfur. Particularly suitable anti-dandruff compositions are shampoos and hair tonics.

The cosmetic or pharmaceutical compositions/ products as disclosed herein preferably are aqueous compositions, i.e. compositions which comprise water.

It is furthermore advantageous, that the water content in said cosmetic or pharmaceutical products according to the present invention is at least about 30 wt.-%, preferably at least about 40, 45, 50, 60, 70, 80, 90 wt.-%, such as e.g. in the range of from 30 to 90 wt.-%, such as from 40 to 90 wt.-%, from 45 to 90 wt.-% or from 50 to 90 wt.-%, based on the total weight of the composition. Further suitable ranges are from 30 to 75 wt.-%, from 30 to 70 wt.-%, from 30 to 60 wt.-% and from 40 to 60 wt.-%.

In a particular embodiment, the compositions according to the present invention are cosmetic products intended to be topically applied to mammalian keratinous tissue such as in particular to human/animal skin or the human/animal scalp. Such compositions/products are also called dermatological compositions. Thus, preferably in all embodiments of the present invention the cosmetic compositions are topical cosmetic (i.e. dermatological) compositions/ products with all the definitions and preferences as given herein.

The topical cosmetic products according to the present invention may be leave- on or rinse-off compositions, and include any cosmetic product applied to a human body, primarily for improving appearance, cleansing, odor control or general aesthetics. Preferably the cosmetic products of the present invention are leave-on compositions/products.

It is well understood that the cosmetic compositions/products according to the invention intended for topical application comprise a physiologically acceptable medium, i.e. a medium compatible with keratinous substances, such as the skin, mucous membranes, and keratinous fibers. In particular, the physiologically acceptable medium is a cosmetically acceptable carrier. In all embodiments of the present invention, it is preferred that the carrier comprises water.

The term "cosmetically acceptable carrier" (also referred to herein as carrier) refers to all vehicles/ carriers conventionally used in cosmetic compositions, i.e. which are suitable for topical application to the keratinous tissue, have good aesthetic properties, are compatible with the actives present in the composition/products, and will not cause any unreasonable safety or toxicity concerns. Such carriers are well-known to one of ordinary skill in the art and can include one or more compatible liquid(s) or solid filler diluent(s), excipient(s), additive(s) or vehicle(s) which are suitable for application to skin.

The exact amount of carrier will depend upon the actual level of the active ingredients and of any other optional ingredients that one of ordinary skill in the art would classify as distinct from the carrier (e.g., other active ingredients).

The cosmetic products of the present invention preferably comprise from 50% to 99.995%, such as from 50% to 99.95, more preferably from 60% to 99.995%, such as from 60% to 99.95, still more preferably from 75% to 99%, and most preferably, from 80% to 98% such as 90% to 98%, by weight of the composition/product, of a carrier, based on the total weight of the composition.

The cosmetic compositions/ products in accordance with the invention can be in the form of a liquid, lotion, a thickened lotion, a gel, a cream, a milk, an ointment, a paste, a powder, a make-up, or a solid tube stick and can be optionally be packaged as an aerosol and can be provided in the form of a mousse such as an aerosol mousse, a foam or a spray foam, a spray, a stick.

Preferably the cosmetic compositions/products according to the present invention are in the form of lotions, creams, gels, and tonics. These product forms may be used for a number of applications, including, but not limited to, hand and body lotions, facial moisturizers, anti-ageing preparations, make-ups including foundations, and the like. Any additional components required to formulate such products vary with product type and can be routinely chosen by one skilled in the art.

If the cosmetic compositions/products of the present invention are formulated as an aerosol and applied to the skin as a spray-on product, a propellant is added to the composition.

The cosmetic compositions/products according to the present invention can be prepared by conventional methods in the art such as e.g. by admixing the retinoid mixture or composition comprising said mixture of cis and trans isomers of retinoids as defined herein, having a cis/trans ratio of less than 0.01 with all the definitions and preferences given herein with the cosmetically acceptable carrier.

The cosmetic composition/ products may comprise further ingredients, which may form part of the carrier. Such ingredients are particularly surfactants, emulsifiers, thickeners, and oils. Such suitable surfactants, emulsifiers, thickeners, and oils are well known to a person skilled in the art.

The cosmetic compositions/products of the invention (including the carrier) may comprise further conventional (cosmetic) adjuvants and additives, such as preservatives/antioxidants, fatty substances/oils, water, organic solvents, silicones, thickeners, softeners, emulsifiers, antifoaming agents, aesthetic components such as fragrances, surfactants, fillers, anionic, cationic, non-ionic or amphoteric polymers or mixtures thereof, propellants, acidifying or basifying agents, dyes, colorings/ colorants, abrasives, absorbents, chelating agents and/or sequestering agents, essential oils, skin sensates, astringents, pigments or any other ingredients usually formulated into such compositions.

If nothing else is stated, the excipients, additives, diluents, etc. mentioned in the following are suitable for the compositions according to the present invention.

The necessary amounts of the cosmetic and dermatological adjuvants and additives can, based on the desired product, easily be determined by the skilled person.

The additional ingredients can either be added to the oily phase, the aqueous phase or separately as deemed appropriate. The mode of addition can easily be adapted by a person skilled in the art.

Examples of suitable cosmetic surfactants, emulsifiers, thickeners, oils, excipients, diluents, adjuvants, additives as well as active ingredients commonly used in the skin care industry which are suitable for use in the cosmetic compositions of the present invention are for example described in the International Cosmetic Ingredient Dictionary & Handbook by Personal Care Product Council (http://www.personalcarecouncil.org/), accessible by the online INFO BASE (http://online.personalcarecouncil.org/jsp/Home.jsp), without being limited thereto.

The cosmetically active ingredients useful herein can in some instances provide more than one benefit or operate via more than one mode of action.

Of course, one skilled in this art will take care to select the above mentioned optional additional ingredients, adjuvants, diluents and additives and/or their amounts such that the advantageous properties intrinsically associated with the combination in accordance with the invention are not, or not substantially, detrimentally affected by the envisaged addition or additions.

The cosmetic compositions/products according to the present invention are in particular skin care preparations, functional preparations and/or hair care preparations such as most in particularly skin or hair care preparations.

Examples of skin care preparations are, in particular, light protective preparations (sun care preparations), anti-ageing preparations, preparations for the treatment of photo-ageing, body oils, body lotions, body gels, treatment creams, skin protection ointments, moisturizing preparations such as moisturizing gels or moisturizing sprays, face and/or body moisturizers, as well as skin lightening preparations.

Examples of functional preparations are cosmetic compositions containing active ingredients such as hormone preparations, vitamin preparations, vegetable extract preparations, anti-ageing preparations, and/or antimicrobial (antibacterial or antifungal) preparations without being limited thereto. Examples of hair care preparations which are suitable according to the invention and which may be mentioned are shampoos, hair conditioners (also referred to as hair rinses), hairdressing compositions, hair tonics, hair regenerating compositions, hair lotions, water wave lotions, hair sprays, hair creams, hair gels, hair oils, hair pomades or hair brilliantines. Accordingly, these are always preparations which are applied to the hair and the scalp for a shorter or longer time depending on the actual purpose for which they are used.

Preferably in all embodiments of the present invention the skin/functional and/or hair care preparation is a deodorant, an anti-perspirant, an anti- dandruff or an anti-acne composition comprising a mixture of retinoids, particularly retinol and/or retinyl acetate, with a cis/trans ratio as defined herein.

In a preferred embodiment, the cosmetic products/compositions according to the invention are in the form of emulsions and/or gels. Even more preferably, the cosmetic compositions are emulsions which contain an oily phase and an aqueous phase such as in particular O/W, W/O, Si/W, W/Si, O/W/O, W/O/W multiple or a pickering emulsions, PIT-emulsions, nano emulsions, micro emulsions, multiple emulsions (e. g. O/W/O- or W/O/W-type)

The amount of the oily phase (i.e. the phase containing all oils and fats including the polar oils) present in such emulsions such as in particular O/W, W/O, Si/W, W/Si, O/W/O, W/O/W multiple or a pickering emulsions is preferably at least about 10 wt.-%, such as in the range from 10 to 60 wt.-%, preferably in the range from 15 to 50 wt.-%, most preferably in the range from 15 to 40 wt.-%, based on the total weight of the composition.

The oil phase according to the invention preferably comprises oils selected from butylenglykoldicaprylat/-dicaprat, dimethicone, propylenglykoldicaprylat/- dicaprat, dicaprylylether, C_12-15-Alkylbenzoat, C_18-38-fatty acid triglyceride, dibutyladipate, cyclomethicone, 2-phenylethylbenzoat, isopropyl lauroyl sarkosinate, caprylic/capric triglyceride as well as mixtures thereof.

The amount of the aqueous phase present in such emulsions is preferably at least about 20 wt.-%, such as in the range from 20 to 90 wt.-%, preferably in the range from 30 to 80 wt.-%, most preferably in the range from 30 to 70 wt.-%, based on the total weight of the composition.

Advantageously in all emulsions of the present invention the ratio of oily phase to aqueous phase is selected in the range of 40:60 to 30:70. In one particular advantageous embodiment, the cosmetic compositions/products according to the present invention are in the form of an oil-in-water (O/W) emulsion comprising an oily phase dispersed in an aqueous phase in the presence of an O/W emulsifier. The preparation of such O/W emulsions is well known to a person skilled in the art.

If the cosmetic composition/products according to the invention is an O/W emulsion, then it contains advantageously at least one O/W- or Si/W-emulsifier selected from the list of glyceryl stearate citrate, glyceryl stearate SE (self- emulsifying), stearic acid, salts of stearic acid, polyglyceryl-3- m ethylglycosedistearate. Further suitable emulsifiers are phosphate esters and the salts thereof such as cetyl phosphate (e.g. as Amphisol® A from DSM Nutritional Products Ltd), diethanolamine cetyl phosphate (e.g. as Amphisol® DEA from DSM Nutritional Products Ltd), potassium cetyl phosphate (e.g. as Amphisol® K from DSM Nutritional Products Ltd), sodium cetearylsulfate, sodium glyceryl oleate phosphate, hydrogenated vegetable glycerides phosphate and mixtures thereof. Further suitable emulsifiers are sorbitan oleate, sorbitan sesquioleate, sorbitan isostearate, sorbitan trioleate, cetearyl glucoside, lauryl glucoside, decyl glucoside, sodium stearoyl glutamate, sucrose polystearate and hydrated polyisobutene. Furthermore, one or more synthetic polymers may be used as an emulsifier. For example, PVP eicosene copolymer, acrylates/C10-30 alkyl acrylate crosspolymer, and mixtures thereof.

The at least one O/W, respectively Si/W emulsifier is preferably used in an amount of 0.5 to 10 wt.-%, in particular in the range of 0.5 to 6 wt.-%, such as more in particular in the range of 0.5 to 5 wt.-%, such as most in particular in the range of 1 to 4 wt.-%, based on the total weight of the cosmetic composition.

Particular suitable O/W emulsifiers to be used in the cosmetic compositions according to the invention encompass phosphate ester emulsifiers such as advantageously 8-10 alkyl ethyl phosphate, C9-15 alkyl phosphate, ceteareth-2 phosphate, ceteareth-5 phosphate, ceteth-8 phosphate, ceteth-10 phosphate, cetyl phosphate, C6-10 pareth-4 phosphate, C12-15 pareth-2 phosphate, C12-15 pareth-3 phosphate, DEA-ceteareth-2 phosphate, DEA-cetyl phosphate, DEA- oleth-3 phosphate, potassium cetyl phosphate, deceth-4 phosphate, deceth-6 phosphate and trilaureth-4 phosphate.

A particular suitable O/W emulsifier to be used in the cosmetic compositions according to the invention is potassium cetyl phosphate e.g. commercially available as Amphisol® K at DSM Nutritional Products Ltd Kaiseraugst.

Another particular suitable class of O/W emulsifiers are non-ionic self- emulsifying systems derived from olive oil e.g. known as (INCI Name) cetearyl olivate and sorbitan olivate (chemical composition: sorbitan ester and cetearyl ester of olive oil fatty acids) sold under the tradename OLIVEM 1000.

In one particular embodiment, the invention relates to cosmetic compositions/ products with all the definitions and preferences given herein in the form of O/W emulsions comprising an oily phase dispersed in an aqueous phase in the presence of an O/W emulsifier wherein the O/W emulsifier is potassium cetyl phosphate. The amount of oily phase in such O/W emulsions is preferably at least about 10 wt.-%, more preferably in the range of 10 to 60 wt.- %, most preferably in the range of 15 to 50 wt.-%, such as in the range of 15 to 40 wt.-%, based on the total weight of the composition.

Preferably, the cosmetic compositions/products according to the invention further comprise at least one fatty alcohol (co-emulsifier), such as in particular cetyl alcohol, cetearyl alcohol and/or behenyl alcohol. The total amount of one or several fatty alcohols on the topical compositions according to the invention is preferably selected in the range of about 0.1 to about 10.0 wt.-%, in particular in the range of about 0.5 to 6.0 wt.-% with respect to the total weight of the topical composition.

Preferably, the topical compositions/ products according to the invention comprise a thickener in particular if the topical composition is in the form of an emulsion to assist in making the consistency of a product suitable. Preferred thickeners are aluminiumsilicates, xanthan gum, hydroxypropylmethylcellulose, hydroxyethylcellulose, polyacrylates such as carbopol (e.g. Carbopol® 980, 981, 1382, 2984, 5984) or mixtures thereof. Further preferred thickeners encompass acrylate/C_10-30 alkyl acrylate copolymers (such as e.g. Pemulen™ TR-1, Pemulen™ TR12, Carbopol® 1328 by NOVEON) as well as Aristoflex® AVC (INCI: Ammonium Acryloyldimethyltaurate/VP Copolymer).

The cosmetic compositions/products according to the present invention advantageously comprise a preservative. When present, the preservative is preferably used in an amount of 0.1 to 2 wt.-%, more preferably in an amount of 0.5 to 1.5 wt.-%, based on the total weight of the composition.

The cosmetic compositions/products according to the invention have a pH in the range of 3 to 10, preferably a pH in the range of 4 to 8, most preferred a pH in the range of pH 4 to 7.5, such as in the range of 5 to 6.5. The pH is adjusted by methods known to a person skilled in the art, e.g. by using an acid such as e.g. citric acid or a base such as e.g. sodium hydroxide (e.g. as aqueous solution), triethanolamine (TEA Care), Tromethamine (Trizma Base) and Aminomethyl Propanol (AMP- Ultra PC 2000), according to standard methods in the art.

The amount of the cosmetic composition to be applied to the skin is not critical and can easily be adjusted by a person skilled in the art. Preferably the amount is selected in the range of 0.1 to 3 mg/cm² skin, such as preferably in the range of 0.1 to 2 mg/cm²skin and most preferably in the range of 0.5 to 2 mg/cm²skin.

The following examples are provided to further illustrate the compositions and effects of the present invention. These examples are illustrative only and are not intended to limit the scope of the invention in any way.

The following embodiments (1) to (14) are particularly within the scope of the present invention:

(1): A mixture of cis and trans isomers of retinoids, wherein the cis/trans ratio within said mixture is less than 0.01, preferably a cis/trans ratio of 0.0099, 0.0095, 0.009, 0.0085, 0.008, 0.0075, 0.007, 0.0065, 0.006, 0.0055, 0.005, 0.0049, 0.0045, 0.0043, 0.004, 0.0035, 0.003, 0.0028, 0.0025, 0.0022, 0.002, 0.0018, 0.0015, 0.001, 0.0005 or less, such as 0.0001 or less, more preferably ranges of 0.0099 to 0.0001, 0.008 to 0.001, 0.007 to 0.002, 0.0099 to 0.001, 0.005 to 0.001, 0.005 to 0.0001, 0.005 to 0.0005, 0.006 to 0.001, 0.009 to 0.0001, 0.008 to 0.0001, 0.006 to 0.0001, 0.0055 to 0.0001, 0.005 to 0.002, 0.007 to 0.0001, 0.0045 to 0.0001, 0.004 to 0.0001, 0.0035 to 0.0001, 0.003 to 0.0001, 0.005 to 0.0025, 0.004 to 0.0005, 0.006 to 0.0005, 0.006 to 0.0008, 0.006 to 0.0015, 0.006 to 0.002, 0.006 to 0.003, 0.006 to 0.0004, 0.006 to 0.0025, most preferably a cis/trans ratio of 0.0049 to 0.0025.

(2): A composition comprising a mixture of cis/trans retinoids of embodiment (1).

(3): Mixture of embodiment (1) or composition of embodiment (2) comprising retinoids selected from retinol and/or retinyl esters, the retinyl ester being preferably retinyl acetate.

(4): Mixture or composition of embodiment (3), wherein the retinyl ester is retinyl acetate.

(5): Mixture or composition of embodiments (1), (2), (3) or (4), wherein the retinoids are biologically-derived. (6): Mixture or composition of embodiments (1), (2), (3), (4) or (5), wherein the mixture consists of at least about 95% retinyl esters based on all components in the mixture, particularly wherein the retinyl ester is retinyl acetate or at least about 95% retinol based on all components in the mixture.

(7): Mixture or composition of embodiments (1), (2), (3), (4), (5) or (6) used as antimicrobial agent against Cutibacterium acnes, Corynebacterium xerosis and/or Matassezia, preferably Matassezia furfur.

(8): Mixture or composition of embodiments (1), (2), (3), (4), (5), (6) or (7) used for the treatment, prevention and/or lessening of symptoms of disorders or diseases selected from the group consisting of pityriasis versicolor, dandruff, seborrheic dermatitis, atopic dermatitis, psoriasis and acne.

(9): A pharmaceutical or cosmetic composition or product comprising a mixture or composition of embodiments (2), (3), (4), (5), (6), (7) or (8).

10: Composition or product of embodiment (9) comprising at least one further component selected from the group consisting of pharmaceutically or cosmetically acceptable carrier, water and at least one agent selected from the group consisting of surfactants, emulsifiers, thickeners, oils, and mixtures thereof.

11: Cosmetic composition of embodiment (9) or (10), wherein the composition is a shampoo preparation, hair conditioner, O/W emulsion, W/O emulsion or a gel.

12: Method of treating the skin and/or the scalp, said method comprising the steps of contacting the skin and/or scalp with a mixture or composition of embodiments (1), (2), (3), (4), (5), (6), (7), (8), (9), (10) or (11).

13: Method of embodiment (12), for the treatment, prevention and/or lessening of symptoms of itching skin, malodor formation and/or for maintaining a healthy skin homeostasis and/or for maintaining skin microbiome balance.

14: Use of a mixture or composition of embodiments (1), (2), (3), (4), (5), (6), (7), (8), (9), (10) or (11 .for the prevention, treatment and/or lessening of symptoms of itching skin, for the reduction or inhibition of malodor formation, for the maintenance of a healthy skin homeostasis and/or for the maintenance of skin microbiome balance.

15: A method for killing and/or inhibiting the growth of Cutibacterium acnes, Corynebacterium xerosis and/or Matassezia, particularly Matassezia furfur, said method comprising contacting said microbes with a mixture or composition of embodiments (1), (2), (3), (4), (5), (6), (7), (8), (9), (10) or (11).

Examples

Example 1: Antimicrobial efficacy

Retinoid mixture comprising retinyl acetate and retinol as defined herein can be produced as described in W02022090549 (Ex.1), wherein the retinoids are accumulated in the lipid phase with subsequent isolation/extraction with ethanol or the like as known in the art.

The antimicrobial efficacy of retinol ("Retinol mix") and retinyl acetate ("RetAc mix I and II) having different cis/trans ratio has been assessed in analogy to the regulatory challenge test method (NF EN ISO11930). Thus, solutions of the respective retinol and retinyl acetate mixtures (reference samples and inventive mixtures with a purity of about 98%, see Table 1) were prepared in physiological serum with 0.85 wt.-% NaCl under sterile conditions. The presence of cis and trans-isomers were calculated by reversed phase C4 HPLC analysis.

Table 1: cis/trans ratio of tested Retinol mix, retAc mix I and II, and a control ("Reference retinol" and "Reference retAc") as analyzed by HPLC. For further details see text.

The solutions of the active(s) were then deposed in 96-deep well plates (1.6 ml/well). The wells were contaminated with Cutibacterium acnes, Corynebacterium xerosis, and Matassezia furfur, respectively, to obtain the initial contamination. After contamination, each well was thoroughly mixed to ensure a homogeneous distribution of the microbes. Then each plate was incubated at 22°C for 24h. The counting of the (remaining) population was carried out 24h after contamination. The results for Cutibacterium acnes are shown in Table 2 and 3, results for Corynebacterium xerosis in Table 4 and 5, and results for Matassezia furfur in Table 6), respectively.

Table 2: anti-acne activity of retinyl acetate (samples according to Table 1) after contamination with Cutibacterium acnes. The concentration of tested retinyl acetate with cis/trans ratio as indicated in Table 1 was 0.1%. For further details see text.

Table 3: anti-acne activity of retinol (samples according to Table 1) after contamination with Cutibacterium acnes. The concentration of tested retinol with cis/trans ratio as indicated in Table 1 was 0.25%. For further details see text.

As can be seen in Table 2 and 3, the specific cis/trans mixture of retinyl acetate and retinol, respectively, according to the present invention has an excellent effect in anti-acne application, i.e. against growth of Cutibacterium acnes. A retinyl acetate mixture with a cis/trans ratio of 0.003 to 0.0049 was able to reduce Cutibacterium acnes by about 81% ("A R") compared to a reference with a cis/trans ratio of 0.01. The anti-acnes effect towards Cutibacterium acnes of a retinol mixture with a cis/trans ratio of 0.003 was increased by about 30% ("A R") as compared to the reference with a cis/trans ratio of 0.01. The efficacy of commercially available trans-retinol and trans-retinyl acetate, respectively (e.g. Dry Vitamin A-Acetate 500 or Retinol 50 C from BASF or Microvit®A from Adisseo) against growth of Cutibacterium acnes are in the same range as the reference samples (not shown).

Table 4: antimicrobial activity of retinyl acetate (samples according to Table 1) after contamination with Corynebacterium xerosis as applicable in a deodorant. The concentration of tested retinyl acetate with cis/trans ratio as indicated in Table 1 was 0.1%. For further details see text.

Table 5: antimicrobial activity of retinyl acetate (samples according to Table 1) after contamination with Corynebacterium xerosis as applicable in a deodorant. The concentration of tested retinyl acetate with cis/trans ratio as indicated in Table 1 was 0.25%. For further details see text.

The efficacy of retinyl acetate mixtures against Corynebacterium xerosis with cis/trans ratios according to Table 1 could be increased by up to 81% ("A R") as compared to a reference with a cis/trans ratio of 0.01 or a commercially available retinyl acetate sample (data not shown). As shown in Table 5, the use of a cis/trans ratio of about 0.0049 was less effective compared to ratio of about 0.0025.

Table 6: anti-dandruff activity of retinol (samples according to Table 1) after contamination with Malassezia furfur. The concentration of tested retinol with cis/trans ratio as indicated in Table 1 was 0.25%. For further details see text.

As can be seen from Table 6, the cis/trans retinol mixture according to the present invention shows a significantly higher activity of 60% ("A R") against M. furfur and is thus very effective against dandruff as compared to a reference with a cis/trans ratio of 0.01 or a commercially available sample of retinol (not shown).

Example 2: Formulations Cosmetic formulations in the form of gels, emulsions, shampoo, hair cream, lotion, make-up, toner, after-shave, creams, hand sanitizer, anti-transpirant or deodorant are created according to methods known in the art. If not indicated otherwise the pH of the formulations is adjusted to pH 3-7.5 as deemed appropriate. In the following formulations the term "NEW INGREDIENT" refers to retinoids, i.e. retinol (Retinol mix) or retinyl acetate (RetAc mix I or II) with a cis/trans ratio as indicated in Table 1.

Table 7: Retinoid comprising gels. For further details see text.

Table 8: Retinoid comprising O/W emulsions. Palmitoyl Oligopeptide & Palmitoyl Tetrapeptide-7 are given in [ppm]. For further details see text.

Table 9: Retinoid comprising O/W emulsions. Palmitoyl Pentapeptide-4 is given in [ppm]. For further details see text.

Table 10: Retinoid comprising W/O emulsions. Palmitoyl Tripeptide-38 is given in [ppm]. For further details see text.

Table 11: Retinoid comprising O/W emulsion for facial cream. For further details see text.

Table 12: Retinoid comprising shampoo. For further details see text.

Table 13: Retinoid comprising anti dandruff shampoo. For further details see text.

Table 14: Retinoid comprising revitalizing hair cream. For further details see text.

Table 15: Retinoid comprising natural lotion. For further details see text.

Table 16: Retinoid comprising liquid make-up. For further details see text.

Table 17: Retinoid comprising moisturizing toner. For further details see text.

Table 18: Retinoid comprising after shave SPF 15. For further details see text.

Table 19: Retinoid comprising anti-aging serum. For further details see text.

Table 20: Retinoid comprising anti-aging cream. For further details see text.

Table 21: Retinoid comprising hand sanitizer gel. For further details see text.

Table 22: Retinoid comprising microbiome balancing cream. For further details see text.

Table 23: Retinoid comprising antitranspirant. For further details see text.

Table 24: Retinoid comprising natural deodorant. For further details see text.

Claims

1. A mixture comprising cis and trans isomers of retinoids, particularly comprising cis and trans isomers of retinyl acetate and retinol, wherein the cis/trans ratio within said mixture is 1 to more than 100, wherein the ratio is calculated as wt% of cis-isomers compared to wt% of trans-isomers based on total retinoids in said mixture, particularly wherein the mixture comprises less than 0.5 wt% of cis retinyl esters, preferably cis-retinyl acetate, and optionally wherein the mixture comprises less than 0.3 wt% of cis retinol, all based on total retinoids.

2. The mixture according to claim 1, comprising cis- and trans isomers of retinoids, with a ratio of 1:105, 1:105.26, 1:110, 1:111.11, 1:117.65, 1:120, 1:125, 1:130, 1:133.33, 1:135, 1:140, 1:142.86, 1:150, 1:153.85, 1:155, 1:160, 1:165, 1:166.67, 1:170, 1:175, 1:180, 1:181.82, 1:185, 1:190, 1:195, 1:200, 1:204.08, 1:205, 1:210, 1:215, 1:220, 1:222.22, 1:225, 1:230, 1:232.56, 1:235, 1:240, 1:245, 1:250, 1:255, 1:260, 1:265, 1:270, 1:275, 1:280, 1:285, 1:285.71, 1:290, 1:300, 1:305, 1:310, 1:320, 1:325, 1:330, 1:333.33, 1:340, 1:345, 1:350, 1:357.14, 1:360, 1:370, 1:380, 1:390, 1:400, 1:420, 1:450, 1:454.55, 1:460, 1:480, 1:500, 1:520, 1:550, 1:555.56, 1:600, 1:666.67, 1:700, 1:800, 1:900, 1:1000, 1:1200, 1:1500, 1:2000, 1:2500, 1:2800, 1:4000, 1:5000, 1:7000 or less, such as 1:1000 or less, more preferably ranges of 1:101 to 1:10000, 1:125 to 1:1000, 1:140 to 1:500, 1:101 to 1:1000, 1:200 to 1:1000, 1:200 to 1:10000, 1:200 to 1:2000, 1:600 to 1:1000, 1:110 to 1:10000, 1:500 to 1:700, 1:150 to 1:400, 1:200 to 1:500, 1:250 to 1:400, 1:250 to 1:1000, most preferably a cis/trans ratio of 1:100 to 1:500.

3. The mixture according to claim 2, wherein the mixture comprises cis- and trans retinyl acetate with a ratio of about 1:200 to 1:400.

4. The mixture according to claim 2, wherein the mixture comprising cis- and trans retinol with a ratio of 1:333.

5. The mixture according to any one of claims 1 to 4 comprising 1 wt% or less retinal based on total retinoids.

6. The mixture according to any one of claims 1 to 5 with a color value of L* being in the range of 50 to 100, a* being in the range of -25 to 10 and b* being in the range of 40 to 150.

7. A pharmaceutical, food, feed or cosmetic composition comprising a biologically-derived mixture of any of claims 1 to 6.

8. The composition according to claim 7, wherein the biologically-derived mixture according to any one of claims 1 to 6 is biologically produced through fermentation process.

9. The composition according to claim 7 or 8, wherein the mixture according to any one of claims 1 to 6 has an anthropogenic CO₂ emission profile of zero upon biodegradation.

10. The composition according to any one of claims 7 to 9 for use as antimicrobial agent against Cutibacterium acnes, Corynebacterium xerosis and/or Matassezia, preferably Matassezia furfur.

11. The composition according to any one of claims 7 to 9 for use in the preparation of a composition for the treatment, prevention and/or lessening of symptoms of disorders or diseases selected from the group consisting of pityriasis versicolor, dandruff, seborrheic dermatitis, atopic dermatitis, psoriasis and acne.

12. The composition of claim 11 which is a cosmetic composition.

13. Cosmetic method for treatment of the skin and/or the scalp, said method comprising the steps of contacting the skin and/or scalp with a mixture or composition according to any one of claim 1 to 12.

14. Cosmetic method accordint to claim 13, for the treatment, prevention and/or lessening of symptoms of itching skin, malodor formation, for maintaining a healthy skin homeostasis and/or for maintaining skin microbiome balance.