Abstract:

For surveillance of the cosmetic hygiene for cosmetics containing fermented ingredients, 30 batches of cosmetics containing fermented ingredients were subjected to microbiological tests according to the Safety and Technical Standards for Cosmetics （2015 edition）. Additionally, to investigate the influence of the antibacterial system therein on the applicability of bacteria control method and the applicability of microbial counting method, Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Candida albicans and Aspergillus niger were used for test according to Chinese Pharmacopoeia （2020 edition）. The results showed that, the hygienic quality of cosmetics containing fermented ingredients was good, with a pass rate of 96.67%. Among the 30 batches, the positive control of Escherichia coli did not grow in two batches of cosmetics, and the Staphylococcus aureus did not grow in one batch of cosmetics, and Pseudomonas aeruginosa grew normally in all cosmetics. A total of three batches did not pass the applicability of the control bacteria inspection method, and test-solution dilution method was needed to meet the requirements. There were four batches that had very strong antibacterial activity toward Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Candida albicans, i.e., even using 1:100 test solution, the recovery rate of the test bacteria was still less than 0.5, which required the use of membrane filtration method to make the recovery rate of test bacteria reach 0.5-2.0. Among the 30 batches of cosmetics containing fermented ingredients, 5 batches of cosmetics had different degrees of antibacterial activity, which might affect the accuracy of microbial testing results. Currently, commercially available cosmetics containing fermented ingredients are added with chemical preservatives. However, probiotic fermentation ingredients are not only functional ingredients but also good biological preservatives. Thus, cosmetics containing fermented ingredients may seriously affect the detection rate of microorganisms therein. Therefore, it is necessary to conduct a suitability test before microbiological test for such cosmetics.

Key words: cosmetics containing fermented ingredients, microbiological test, applicability, microbial inhibition