GB2037306A

GB2037306A - Cyclodextrin-camomile inclusion complexes and pharmaceutical compositions containing them

Info

Publication number: GB2037306A
Application number: GB7938763A
Authority: GB
Original assignee: Chinoin Gyogyszer es Vegyeszeti Termekek Gyara Zrt
Current assignee: Chinoin Private Co Ltd
Priority date: 1978-11-20
Filing date: 1979-11-08
Publication date: 1980-07-09
Also published as: SU1514240A3; HU176217B; DK491679A; AT363176B; NO155625C; YU280379A; JPS5573617A; NO793731L; NL7908354A; GB2037306B; FI68174C; SE7909505L; DE2944350A1; CH647534A5; FR2441389B1; IT7969222A0; CS223972B2; FR2441389A1; PL219739A1; ATA738579A

Abstract

An abstract of camomile plant material is stabilised as an inclusion complex with cyclodextrin. The complex can be formulated into pharmaceutical and cosmetic compositions or into animal feeds. The material complexed may be obtained from Flores chamomillae and/or Anthemis nobilis and/or Achillea collina. More specifically the complexed material may be "blue-oil" or aroma and/or flavour extracted from camomile plant material.

Description

SPECIFICATION Cyclodextrin-camomile inclusion complexes and pharmaceutical compositions containing them The present invention relates to cyclodextrin camomile inclusion complexes and a process for the preparation of same as well as compositions containing the complexes.

Camomile, HUNGARIAN CAMOMILE (fores chamomil/ae) and blood-wort (Achi//ea co/I/na) widely used in pharmaceutical industry and Roman camomile RAnthemis nobilis) have been known and employed for a long time in therapy because of their active ingredient.

The inflorescence of the plant is utilized, the infusion of which is active in the internal treatment of catarrhal diseases of the stomach, intestine or the bladder, and in the external treatment as a fomenting agent in case of conjunctivitis, sinusitis, or external otitis. The activity is due to the histamine releasing property of camazulene contained in the volatile oil of camomile, which activates the reticulo-endothelial system and hastens the recovery of stubborn torpid type inflammation processes.

Camomile may be utilized by the following methods: 1) infusion is prepared (= camomile tea), which contains flavonoids, coumarins and the aromas and flavours characteristic of camomile, but only partially contains the volatile oil-terpene components responsible for the pharmacological activity.

2) camomile oil is prepared. This oil is not employed directly but incorporated into ointments, creams, baby powders, i.e. generally antiinflammatory compositions. The stability of the oil is poor and the products prepared from this oil lose their stability in a short time. The oil does not have the well known camomile aroma.

Main components of camomile oil: 1-bizabolol camazulene dicycloethers bizabolol-oxide I bizabolol-oxidell pharnezene herniarin Afurther disadvantage of the use of the inflorescence is the steady decrease of the active ingredient content on storage and the plant material is necessarily accompanied by microbiological and parasitic infections. The blue-oil recovered from the inflorescence is free of infection or contamination but the stability thereof is even less certain. The active ingredient content of the blue oil-containing compositions may be warranted only for a short time. Thus none of the commercially available products gives a satisfactory solution of the stability problem of the active ingredient.

The available camomile compositions (liquid or in tablet form) greatly differ in composition from the natural camomile; they contain only a minor part of the original components and consist mainly of decomposition products. For only a short time after manufacture the product is reminiscent of camomile, but a chemical analysis shows significant differences even at this time.

A commercially available liquid preparation was analysed by chromatography - 6 months after manufacture - and altogether two undecomposed camomile oil components could be detected. One component was camazulene amounting to 15 to 20 per cent of the camazulene content of camomile oil. The presumed camazulene is probably only azulene (artificially prepared azulene). The other component which could be detected from camomile drops in traces was 1-bizabolol; the fu rther two detected components were prebably decomposition products.

The composition is a mildly burnt-odoured, brown alcoholic liquid. One single flavone type substance could be found, which however, could not be identified as any of the flavone type components of camomile.

We also tested an "instant tea" prepared from camomile tea by spray drying. According to chromatography the tea did not contain any volatile oil component mentioned above. One - unidentifiable decomposition product could be detected with a specific reagent forterpenes. A great number of flavone-type compounds are present, which are presumably various glycosides of apigenin flavone.

According to the present invention we provide an inclusion complex of cyclodextrin with an extract of camomile plant material. Thus the active ingredient, aroma and flavour of camomile may be stabilized. The so called inclusion complexes are easy to formulate and use and the dosage may be accurately controlled.

Cyclodextrins are closed rings consisting of glyco-pyranose units, their chemical structure consisting of hydrophilic surface and hydrophobic inner hollow. Thus by contacting them in an aqueous solution with hydrophobic molecules so called inclusion complexes are formed. The molecules of aromas or pharmaceuticals enclosed in an inclusion complex are well-protected from external effects (oxygen, heat, light etc.). Thus the active ingredients may be stabilized by formation of inclusion complexes and may be converted directly to pharmaceutical compositions by conventional methods.

The inclusion complex of the present invention may contain as enclosed compound an extract obtained from Fores chamomillae andlorAnthemis nobilis andiorAchi//ea co//inea plants. The inclusion complex may contain preferably "blue oil" material, and/or aromas and flavours extracted from camomile plant material.

The present invention also provides a process for the preparation of the inclusion complex. The inclusion complexes may be prepared by: reacting (t-, ss- or y-cyclodextrin or a mixture of any of these in solution with an extract of camomile plant material, and separating the resulting inclusion complex from the reaction mixture.

The cyclodextrin may be present as a crude fermentation broth obtained in the course of the preparation of said cyclodextrin, or may be present in a partially prehydrolyzed starch solution.

Extracts obtained from Flores chamomillae, Achilles collina and Anthemis nobilis plants are used in the process of the invention. The preparation of the extract - so called blue oil - and/or aroma and flavourings may be carried out by methods knownperse. The complex formation is carried out e.g. at 15-80 C, preferably at 50"C whereafter the reaction mixture is cooled under vigorous stirring.

The cyclodextrin-camomile inclusion complexes are stable, powdery products, which dissociate in water and thus possess camomile activity.

The invention also provides pharmaceutical and cosmetic compositions containing the inclusion complexes. The inclusion complexes may be formulated in pharmaceutical compositions or cosmetics without the danger of the active ingredient's decomposition. The compositions may contain the usual carriers and/or adjuvants such as binding agents, lubricants, flavouring agents and optionally other pharmaceutically active ingredients. The complex can also be formulated into animal feeds orfeed premixes.

According to the invention a combined composition may also be prepared containing a complex of cyclodextrin formed with camomile blue oil, and another complex formed with aroma and/orfiavourings in a variable ratio.

It is particularly advantageous to use the inclusion complex of blue oil as a pharmaceutical or cosmetic intermediate as so far only such aromas and flavourings have been used for the same purpose which can be found in the form of an aqueous extract and which do not possess any essential pharmacological activity.

The following advantages of the inclusion complexes of the invention may be enumerated: 1) the complexes are prepared from a natural active ingredient, 2) the complex contains all the pharmacologically important components of the active ingredient, 3) the product is stable against heat, light, oxygen and metal ions, etc.

4) the product is a crystalline powder, which may be easily compressed to tablets, 5) well administrable pharmaceutical preparations may be obtained having a constant active ingredient content.

The details of the invention are illustrated by the following Examples which are given merely for illustration and not for limitation.

Example 1 10.0 g of ss-cyclodextrin moisture content: 14.46%) are dissolved in 180 ml. of 30% by vol aqueous ethanol under steady stirring at 50"C. A solution of 1 g. of camomile oil in 10 vol % aqueous ethanol is added dropwise to the ss-cyclodextrin solution. 3 to 4 minutes after the addition is ended the system becomes turbid and the crystalline adduct starts to crystallize. The system is slowly cooled to room temperature (4.5-5 hours). Stirring is stopped and the complex is put on ice for 16 hours. The mixture is then filtered through a sintered glass filter and dried above phosphorous pentoxide at room temperature. Thus 10.06 g of crystalline light-blue camomile oil ss-cyclodextrin complex is obtained.

Active ingredient content of the complex. 8.12%, yield related to camomile oil: 75.04%. The efficiency of the complex formation may be increased by using a high speed stirrer. Empirical formula and molecular weight may be given only reiated to ss-cyclodextrin: (C6H1005)7, MACS: 1135.0. Approximate average molecular weight of sesquiterpene derivatives of camomile oil is 230, thus the average molecular weight of the complex including about 7% water amounts to approximately: 1460.

No structural formula for the product can be given since not all the active ingredient components of natural camomile are yet known.

The product obtained according to Example lisa light blue, microcrystalline powder having a mild camomile odor. It has no melting point; upon heating it starts to decompose at about 200"C i.e. at a temperature characteristic for the decomposition of ss-cyclodextrin.

Solubility: in distilled water 0.030-0.035 9./100 ml.

in 96% ethanol 0.030 go100 ml.

in contact with benzene and chloroform only camomile oil is dissolved, ss-cyclodextrin is practically insoluble in these solvents (data relate to 25 C).

The aqueous solutions of the complexes are always somewhat turbid.

The complex is rather stable at room temperature; it may be stored at least for 5 years without decomposition.

Stability of the product of Example 1 against oxidation is shown by oxidation tests according to Warburg.

The results are summarized in Table I.

TABLE I Oxygen consumption rd/mg.

Time (hours) camomile oil l'-CD-camomile complex 70 6 2 80 14 4 120 18 5 160 23 7 200 30 7 240 58 7 280 80 7 320 100 7 The oxygen consumption of the complex may be neglected in comparison with the oxygen consumption of the pure camomile oil.

Neither camomile oil nor cyclodextrin are toxic when administered peros. The two components do not form any covalent bond and the complex dissociates under physiological conditions.

Activity of the complex on the reticulo-endothelialsystem.

The phagocyte function of the recticuto-endotheliai system is generated by histamine as a chemical activator. Upon the effect of histamine the endothelical cells of peripheral capillary vessels are converted to phagocytes within a short time which accumulate within themselves Indian ink injected in the blood stream like the RES cells of liver, spleen or bone marrow.

Since camomile also releases histamine and activates RES, by following the elimination ofthe Indian ink injected intravenously it became possible to compare the efficacy of pure camomile oil with the inclusion complex.

The experiments were carried out by using CFLP male mice weighing 25 (+2) g. (CFLP stands for an international strain of stable genetic consititution). The method was substantially the same as the method of Janscd (Jancs6, M.: Orvosok Lapja, 1947,111.28, 1025)0.5 ml. of 10% Indian ink/25 g. body weight was injected into the tail vein of the mice in physiological salt solution. To this solution 1% gelatine is added in order to ensure the stability of the colloidal system. A suspension of carbon granules having a diameter of 0.2 -1t't was used as the injection of a solution containing granules of a bigger size caused the filling of the lung by ink and the animals died of embolism.Before the administration of the ink 0.5 ml. of a physiological salt solution had been injected twice under the skin of the mice. The animals were treated per os with 5 mg.

of camomile oil or 5 mg. of the product of Example 1 containing camomile oil one hour before the administration ofthe ink.

The elimination of the ink from the blood was followed by photometry.

Following the intravenous injection of the ink every 5 minutes 10 ml. of blood was sucked into the measuring pipette, homogenized in mildly alkalized water and the light absorption of the solution was determined by photometry.

The elimination of the ink in the treated and the untreated animals is summarized in Table II.

Toxicity assays of the camomile-p-cyclodextrin inclusion complex show that the complex is not toxic.

No toxicity could be observed when administering camomile complex to 10 female mice (body weight 20-25 g.) per os in the form of a suspension in an amount of 3000 mg./kg. body weight (corresponding to 234 mg. active ingredient kg. body weight) and to 10 male mice (body weight 20 to 25 g) under similar circumstances up to 3000 mg.. kg. body weight (corresponding to 264 mg active ingredient/kg. body weight).

5000 mg.;kg. body weight camomile complex (corresponding to 430 mg. of active ingredient) was administered to 10 female and 10 male rats and no toxic phenomenon was observed.

TABLE II Elimination of ink from blood [Administration of ink increased the blood extinction by 25% on average. The data in the table show the decrease of this value in groups consisting of 8 animals (average values)].

Timeafterthe Et - Et injection of ~~~~~~~~~~~~~~ .100 the ink E0 Camomile Product according Control oil to Example 1 between 10 to 20X minutes 2.63 7,78 6.75 between 20 to 30 minutes 3.43 3.30 5.60 between 30 to 40 1.69 5.47 4.67 minutes total between 10 to 40 minutes 8.15 16.55 17.12 x = extinction value relating to time 0 cannot be determined exactly Et = extinction in time t after the injection of the ink E0 = extinction measured before the injection of the ink Example 2 Preparation of camomile aroma-ss-cyclodextrin inclusion complex 10 g. of ss-cyclodextrin are dissolved in 30% by vol. aqueous ethanol at 50"C, whereafter 2.5 g. camomile aroma obtained from 30 g. of camomile inflorescence are added in 10 ml. of ethanol. The system became turbid in the 10th to 12th minute after the addition. The system is then not heated any longer and is cooled to room temperature under steady stirring for 4 hours. The mixture is then allowed to stand in a refrigerator for 16 hours followed by filtration through glass4ilter and dried above phosphorous pentoxide. 10.8 g. of yellowish white crystalline product is obtained; active ingredient content is about 12 % (measured by weight).

When preparing a complex containing flavours and aromas of camomile inflorescence one may preferably use an extract of Roman camomile (Anthemis nobilis) as starting material as the main source of flavours and aromas, and containing only a small part of the characteristic components of blue-oil.

Example 3 Sensory evaluation of "Complete" camomile tea The product obtained according to Example 1 contains all the pharmacologically important components of camomile, but does not contain the characteristic aroma components of camomile. In most cases these components are not required, but in some cases the aroma may be desirable as well. The product according to Example 2 contains these aroma components, thus a "complete" camomile tea may be obtained by combining the two products.

Accordingly the following samples have been compared: 4.5 g. of the product according to Example 2 (camomile-aroma complex) + 0.5 g. of the product according to Example 1 (camomile oil-complex) in 1 liter of water and 2.2 g. of camomile inflorescence boiled in 1 liter water.

The assay was carried out by triangular comparative test. The samples contained camomile infusion and cyclodextrin inclusion complex tea in the same number. The samples were cooled to 20 or 40"C and in order to eliminate the subjective influencing effect of the different colours the tea was placed to vessels covered in dark paper.

The sensory test was carried out by 11 observers at 20 and 40"C; the identity was guessed correctly by 10 observers: among them the infusion of camomile was preferred by 3 observers, the cyclodextrin inclusion complex was preferred by 7 observers.

Accordingly: the significance level of the difference test is 99.9% and the significance level of the qualitative test is 99.0%.

The test showed that the observers giving the correct answer preferred the tea prepared by dissolving cyclodextrin inclusion complex at a significance of 99.9%.

Example4 1 g. of the product prepared according to Example 1 corresponds to 8.40 g of air-dry plant material. The product may be utilized in the veterinary field in various cases of intestinal inflammations of pigs, cattle, horses, dogs, cats etc. as follows: a) in each case when the gastro-intestinal inflammations are caused by dietetic mistakes. In such cases the animal should be administered 50 to 150 mg. complex/kg. body weight (or a corresponding tablet dose) 3 to 5 times for 2-3 days until diarrhoea ceases. The product is preferably combined with therapeutically usual amount of charcoal. Until complete recovery instead of drinking water an aqueous solution prepared from the camomile complex of Example 1 at body temperature is given to the animals.

b) in cases when the gastro-intestinal inflammation of various degrees of severity is caused by pathogens (coliform bacteria, etc:) camomile complex may be combined - after a preliminary treatment with a laxative - with other antibacterial agents such as oxolinic acid. The combination may be administered in drinking water or admixed with the fodder until the animals is recovered. Drinking water may be replaced by an aqueous solution prepared from camomile cyclodextrin until the recovery of the animal.

c) in case of external inflammation diseases of various domestic animals a talcum, or a granulate containing camomile cyclodextrin may be used placed between muslin bandages. Before placing it on the inflamed part of the body, it is soaked in water for a short time.

d) A solution or suspension prepared from the product of Example 1 may be employed for the treatment of conjunctivitis, or inflammations of the mouth, anus or uterus.

e) In a few days after weaning the incidence of a non-specific enteritis of non-infectious origin in pigs is 30 to 90%. The frequency and intensity of enteritis may be decreased or the number of days necessary to overcome enteritis may be reduced by using camomile oil-(S-cyclodextrin in the fodder. Simultaneously an increased fodder uptake and better utilization of the fodder may be observed.

3.42 kg. of the camomile oil-(1-cyclodextrin complex prepared according to Example 1 are supplemented with flour to 50 kg, and a homogeneous mixture was prepared. This premix was diluted with fodder to a 200-fold amount, i.e. 10000kg. of weaned piglet fodder were prepared, 0.3 kg. of which contained 15 mg. of camomile oil (0.5 kg. is an average fodder uptake per day of a piglet of weaning age). Experiments were carried out in two different pig breeding farms. In farm I tetra-hybrid pigs were weaned at an age of 28 days and the animals were fed according to recipies of the Hungarian firm Phylaxia with dry feed by self-feeding system. In farm II similar pigs of similar age were fed from a feeding trough according to Central Soya recipies with dry feed.The number of animals and the experimenta results are contained in the following Tables.

The Tables show that the daily weight gain is significantly better in the group treated with camomile complex, than in the control group. At the same time the amount of fodder necessary per 1 kg. ofweight gain is smaller.

The daily weight gain of the animals exceeded by 25 to 30 g. the weight gain of the control and to achieve 1 kg. of weight gain the required amount of fodder could be reduced by 100 g. to 125 g.

Farm No. I Death, weight gain and fodder utilization parameters Group treated with camomile Control groups Age (days) at the beginning of the experiment 29.56 + 4.60 25.50 t 2.14 at the end of the experiment 49.56+ 4.60 45.50 + 2.14 Number of animals at the beginning of the experiment 309 306 at the end of the experiment 299 293 Death (individuals) 10(3.24%) 13(4.252/o) enteritis 8 (2.59 %) 12 (3.92 %) other 2 (0.65 %) 1(0.33%) Average weight (kg.) at the beginning of the experiment 6.29 1 1.12 5.58 + 0.71 at the end of the experiment 12.8812.12 11.471.17 Average weight gain (kg.) 6.59 5.89 Average weight gain per day (9.) 330 295 Total consumed fodder (kg.) 4350 4050 Average daily fodder consumption (g.) 715 676 Fodder required for 1 kg.

of daily weight gain 2.171 2.296 Farm No. II Death, weight increase and fodder utilization parameters Group treated with camomile Control group Age (days) at the beginning of the experiment 33.17 + 3.54 29.68 + 2.84 at the end of the experiment 60.17 + 3.54 56.68 + 2.84 Number of animals (pieces) at the beginning of the experiment 234 211 at the end of the experiment 225 206 Death (individuals) 9 (3.85 %) 5 (2.37 %) enteritis 6 (2.56 %) 3(1.42%) other 3 (1.28 %) 2 (0.95 %) Average weight (kg.) at the beginning of the experiment 8.931 1.35 7.95 + 1.14 at the end of the experiment 17.201 2.23 15.541 2.10 Average weight gain (kg.) 8.27 7.59 Average weight gain per day (g.) 306 281 Total consumed fodder (kg.) 4850 4206 Average daily consumed fodder (9.) 783 747 Fodder needed to 1 kg. of weight gain (kg.) 2.556 2.658 Example 5 Baby powder Composition: Camomile extract ss-CD 5.0g.

Azulenol 100 % ss-CD 5.0 g.

basic magnesium carbonate 70.0 g.

talc 920.0 9.

1000.0 g.

Camomile an d azu lenol-B-CD inclusion com plexes are thoroughly pulverized to pass fu Ily through a O.16 mm mesh screen (screen classification according to Ph. Hg. VI.). After screening, the mixture is homogenized with a basic magnesium carbonate and talc. The final baby powder is screened again and filled into suitable castors.

Example 6 Dry shaving powder Composition: camomile extract-ss-CD 5.0g.

azulenol-100 %-ss-CD 5.0g.

kaolin 130.0 g.

magnesium carbonate 130.0 g.

starch (ANM) 116.0g.

cetyl alcohol 20.0g magnesium stearate 30.0 g.

zinc oxide 50.0 g.

talc 514.0 9.

1000.0 g.

Camomile and azulenol-p,-CD inclusion complexes are thoroughly pulverized to pass fully through a 0.16 mm mesh screen (Ph. Hg. VI. screen classification). The thus prepared active ingredient is admixed with starch (ANM-Amylum non mucilaginosum special talc starch) followed by mixing the remaining powder components in an increasing amount. The mixture is then filled into castors or optionally pressed into cylindrical form.

Example 7 Tea tablets Composition: camomile extract--ss-CD 20.0 g.

azulenol-100 %-ss-CD 20.0 g.

ascorbic acid 44.0 g.

sodium hydrogen carbonate 15.0 g.

glycerol monostearate 1.0g.

From ascorbic acid and sodium bicarbonate separate granules are prepared with glycerol monostearate by conventional techniques of pharmacy. Camomile and azulenol-ss-CD inclusion complexes are thoroughly pulverized to pass fully through 0.16 mm mesh screen (Ph. Hg. VI. screen classification). Camomile and azulenol-ss-CD inclusion complexes are admixed with the granules of ascorbic acid and sodium bicarbonate and compressed into 0.5 g tablets.

Example 8 Tea Component-ratio of tea 1.8 g. of camomile extract-(3-CD complex and 0.2 g. of camomile oil ss-CD complex are dissolved in 100 ml. of hot water.

Claims

1. An inclusion complex of cyclodextrin with an extract of camomile plant material.

2. An inclusion complex according to claim 1 comprising as complexed material an extract obtained from Flores chamomillae and/or Anthem/s nobilis andlorAchillea collina.

3. An inclusion complex as claimed in claim 1 or 2 comprising as complexed material "blue-oil" extracted from camomile plant material.

4. An inclusion complex according to claim 1 or 2 comprising as complexed material aroma and/or flavour extracted from camomile plant material.

5. A mixture of the inclusion complexes of claims 3 and 4.

6. An inclusion complex as claimed in claim 1, substantially as illustrated in Example 1 herein.

7. An inclusion complex as claimed in claim 1, substantially as illustrated in Example 2 herein.

8. A process for the preparation of an inclusion complex according to claim 1 which comprises reacting (t-, - or ,-cyclodextrin or a mixture of any of these in solution with an extract of camomile plant material, and separating the resulting inclusion complex from the reaction mixture.

9. A process as claimed in claim 8 wherein said cyclodextrin is present as a crude fermentation broth obtained during the preparation of said cyclodextrin.

10. A process as claimed in claim 8 wherein said cyclodextrin is present in a partially pre-hydrolyzed starch solution.

11. A process as claimed in any of claims 8 to 10 wherein said extract has been obtained from Flores chamomillae andlorAnthemis nobilis and/or Achilles collies.

12. A process as claimed in any of claims 8 to 11 wherein said extract comprises "blue-oil" extracted from camomile plant material.

13. A process as claimed in any of claims 8 to 11 wherein said extract comprises flavour and/or aroma extracted from camomile plant material.

14. A process as claimed in any of claims 8 to 13 wherein complex formation is performed at a temperature of 15 to 80"C, followed by slow cooling of the reaction mixture under vigorous stirring.

15. A process as claimed in claim 14 wherein complex formation is performed at about 50"C.

16. A process as claimed in claim 8 substantially as hereinbefore described with reference to Example 1 or2.

17. A pharmaceutical composition containing an inclusion complex according to any of claims 1 to 3,5 or 6 as active ingredient and a pharmaceutically acceptable carrier and/or adjuvant.

18. A cosmetic preparation which comprises an inclusion complex according to any of claims 1 to 7 and a cosmetic carrier.

19. An animal feed or feed premix comprising an inclusion complex according to any of claims 1 to 3, 5 or6.

20. A pharmaceutical composition substantially as illustrated in Example 5, 7 or 8.

21. A cosmetic preparation substantially as illustrated in Example 6.

22. An animal feed substantially as illustrated in Example 4.

23. Use of the complex of claim 1 as a pharmaceutical agent for human or veterinary treatment.