DE2338462B2 - PROCESS FOR CHEMICAL PRESERVATION - Google Patents

Description

A subculture was grown from these germs and this was grown on the substrate mentioned above inoculierL

3. Test temperature

Since the effect of the preservatives is 5, we carried out the experiments at 18-22 ° C (»Soaps,

rising temperature rises, but on the other hand the oil, fats, waxes ", 98th year, No. 13/1972, p. 423 /

cosmetics, pharmaceuticals and 424) to be preserved. Food is stored at room temperature,

4. Determination of the number of germs in the substrates mixed with microorganisms

can be used as a benchmark for antimicrobial effectiveness can be used.

The test results are compiled in Tables 1 to 3 below. Table 4 contains for comparison, the results of corresponding tests without the use of parahydroxybenzoic acid esters.

Substrates, with and without the addition of the invention mixture to be used, were contaminated with the microorganisms and the course of the Development of germs followed by counting germs. With antimicrobial effectiveness the substances decreases the germ content decreases and the substrates become germ-free. The time until sterility occurs

Table 1

Antimicrobial effectiveness of hexanoic acid monoe'.yceride in combination with a pHB ester combination (Methyl ethyl ester 1: 1)

Substrate:

3% oleyl alcohol + 10 AO

l "o protein hydrolyzate

pH 6.0 test temperature 18-20 ° C

Inoculated germs 900,000 / ml

Addition of:

Germ content / ml without additives 0.5% hexane 0.3% pHB- 0.5% hexane 1.0% hexane 1% hexane 1.0% hexane after sour mono Ester acid mono- acid mono- acid mono- acid mono- glyceride combination glyceride glyceride glyceride glyceride 0.3% pHB- 0.3% pHB- 0.15% pHB- Ester Esier- Ester combination Kcimbination combination

1 day

4 days

8 days

15 days

25 days

36 days

50 days

15000000 40000000 31000000 24000000 19000000 16000000 12000000

2000000

18000000

20000000

4,500,000

2,500,000

450

80000

1500000

1200000

1000000

800000

250000

160000

80000 400000

300,000

150000

000

000
2000000
540000
450000
400,000
200,000
000

2CK) OOO
1000
0
0
0
0
0

1000000

1500000

400,000

400,000

300,000

60000

20000

Table 2

Antimicrobial effectiveness of octanoic acid monoglyceride in combination with a pHB ester combination (Methyl / ethyl ester 1: 1)

Substrate:

3% oleyl alcohol + 10 AO 1% protein hydrolyzate pH 6.0 Test temperature 18-2O ⁰ C Inoculated germs: 900,000 / ml

Addition of:

Germ content / ml
after

Without addition

0.5% octanoic acid monoglyceride

0.3% pHB ester (combination 0.5% octanoic acid monoglyceride
0.3% pHB ester combination

1.0% octanoic acid monoglyceride
0.3% pHB ester combination

1.0% octanoic acid monoglyceride 0.15% pHB ester
combination

ITag
4 days
8Taee

150000 (X) 40000 (XM) 31000000

1200000

800000

60000

1500000 1200000 1000000 000

800

50

100
7th
0

9000

continuation

iCeimgebaU / inl Without addition after

0.5% octanoic acid craonoglyccride

0.3% pHB-Estcr-Kombinalion 0.5% octanoic acid monoglyceride 0.3% pHB-Esler combination

1.0% octanoic acid monoglyceride 0.3% pH B-ester combination

1.0% octane

acid onono-

glyceride

0.15% pHB-

Donkey

combination

Days
Days
Days
50 days

24000000 19000000 16000000 12000000

40000

30000

10,000

5000

800000

250000

160

80 0
0
0
0

0
0
0
0

0 0 0 0

Table 3

Antimicrobial effectiveness of the moncacetyl or monopropionyl derivatives of monoglycerides medium-chain

Fatty acids in combination with a pHB ester combination (methyl / ethyl ester 1: 1)

Substrate:

3% oleyl alcohol + 10 AO

1% protein hydrolyzate

pH 6.0 test temperature 18-20 ° C

Inoculated germs 550,000 / ml

Kcim content / ml after

Without addition

1% I-Oclanoyl-3-acetyIglycerin

1% 1-hexanoyl

T-propionyl

glycerin 0.3% pHB-Estcr combination

1% 1-oclanoyl 3-acctylglycerin 0.3% pHB ester combination

1.0% I-hexa-

noyl-3-propionyl-

glycerin

0.3% pHB-

Ester

combination

1 day

4 days

8 days

15 days

25 days

36 days

50 days

7000000

12000000

20000000

15000000

11000000

3000000

2,500,000

150000

80

45000

20000

5000

250

60

38

9

2

900

2000000

500000

500000

800000

400,000

200,000

000

5500
150
0
0
0
0
0

4000 200 0 0 0 0 0

Table 4

Antimicrobial effectiveness of fatty acid monoglycerides or their monoacetyl and monopropionyl

derivatives

Substrate:

3% oleyl alcohol + 10 AO 1% protein hydrolyzate pH 6.0 Test ^{temperature 18-20 °} C Inoculated germs 160,000 / ml

Addition of:

Kcimgchalt / m! after

0.8% hexanoic acid- 1.3% hexanoic acid- 0.8% octanoic acid- 1.3% octanoic acid- 1.3% 1-hexanoyl- 1.3% 1-octanoyl monoglyceride monoglyceride monoglyceride monoglyceride 3-propionyl-3-acclylglyceride

glycerin

ITag

4 days

8 days

15 days

25 days

36 days

Sn Tm ve

: $ ooooo

900000

700000

200,000

120000

70000

40000

200,000

800000

600000

40000

20000

15000

10,000

18th

400,000

350000

150000

60

40000

12 15000

000

000

CKM)

120000 100,000 100,000 100,000 70000 90,000 50,000 60000 3000 40,000 200 1,500 0 0

Claims (2)

: Claim: i-s process for the chemical preservation of cosmetics, pharmaceuticals and foodstuffs with the addition of parahydroxybenzoic acid esters. characterized in that the substrate to be preserved is given a mixture of a) 0.5 to 1.0 percent by weight of a compound of the general formula (I) '1S in which R is a straight-chain aliphatic hydrocarbon radical with 5 to 7 carbon atoms and R1 is hydrogen, an acetyl radical or is a propionyl radical, and from zo b) 0.15 to 0.3 percent by weight of the methylundoder ethyl ester of parahydroxybenzoic acid is added. It is known. Preserve food by adding parahyuroxybenzoic acid esters. However, a disadvantage of these preservatives is their low solubility in the substrates to be preserved, which limits their inherently good antimicrobial effectiveness, so that in many cases adequate preservation cannot be achieved. A process has now been found for the chemical preservation of cosmetics, pharmaceuticals and foodstuffs with the addition of parahydiroxybenzoic acid esters, which is characterized. that the substrate to be preserved is a mixture of a) 0.5 to 1.0 percent by weight of a compound of the general formula RCO-CH2-CH (OH) -CH2-O-R1 (1) O in which R is a straight-chain aliphatic hydrocarbon radical 5 to 7 carbon atoms and R1 is hydrogen, an acetyl radical or a propionyl radical, and from b) 0.15 to 0.3 percent by weight of the methyl and / or ethyl ester of parahydroxybenzoic acid is added. Compounds of the general formula (I) which are suitable for the process according to the invention are the monoglycerides of hexane, heptane and octane carboxylic acids and their monoacetyl and monopropionyl derivatives. The monoglycerides mentioned can be obtained by reacting the corresponding carboxylic acids with glycide in the presence of a basic catalyst and at elevated temperature. The monoacetyl and monopropionyl derivatives can be prepared in the same way by reacting the corresponding carboxylic acids with glycidyl acetic or propionic acid. The monoglycerides or monoglyceride derivatives to be used according to the invention are generally added to the substrates to be preserved in amounts of 0.5 to 1.0 percent by weight, based on the weight of the substrate. The amount of methyl and / or ethyl ester of parahydroxybenzoic acid used is between 0.15 and 03 percent by weight, also based on the weight of the substrate. In many cases it is advantageous to use the parahydroxybenzoic acid ester in the form of a combination of equal parts of the methyl and ethyl esters. The mixture of monoglycerides or monoglyceride derivatives and parahydroxybenzoic acid esters to be used according to the invention unexpectedly results in an extraordinary synergistic effect. The monoglycerides or monoglyceride derivatives can be incorporated very easily into cosmetics, pharmaceuticals and foods. They increase the antimicrobial effectiveness of the parahydroxybenzoic acid ester to a very considerable extent. Since they are also odorless and tasteless, the smell and taste of the preparations preserved with them are not affected. They are also physiologically harmless, do not have any irritating effect on the skin and are consequently ideal for the preservation of cosmetics, pharmaceuticals and foods. An additional advantage of the mixture to be used according to the invention is that its antimicrobial effectiveness is generally not adversely affected by other substances. Testing the antimicrobial effectiveness Individual variants of the mixture to be used according to the invention were tested for their antimicrobial effectiveness and compared with the individual components. The tests were carried out under the following conditions: 1. The substrate used An aqueous solution of 3% ethoxylated (10 mol ethylene oxide) oleyl alcohol was used as the substrate and 1% protein hydrolyzate used. The results when testing the antimicrobial effectiveness of preservatives in this substrate can be transferred to other substrates (»soap, oils, Fette, Wachse ”, 94th year, p. 647 [1968]). 2. Microorganisms In order to create practical conditions, a germ mixture of the following composition was chosen: Gram negative germs Oram positive germs Pseudomonas aeruginosa
Aerobacter aerogenes
Escherichia coli
Proteus vulgaris Mixed germs 1 (from a
Protein hydrolyzate isolated)
Mixed germs II (from a
Protein-fatty acid ^ condensate isolated) Staphylococcus aureus
hemolyticus
Staphylococcus albus
Streptococcus
without hemolysis
Bacillus subtiiis Candida albicans