Preparation of Antimicrobial Compounds from Lactic Acid Bacteria and Bacillus spp. for Cosmetic Application

• Main Authors: Wan-Tzu Li, 李婉慈
• Other Authors: Chien-Ku Lin
• Format: Others
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/88717100420660310210

碩士 === 弘光科技大學 === 食品暨應用生物科技所 === 99 === Lactic acid bacteria (LAB) and Bacillus are usually offered as probiotic microbes nowadays, and are beneficial for the health of humans and animals. Recently, the antimicrobial compounds isolated from probiotics have been identified and used as natural antagonistic ingredients to replace chemical inhibitors in food and cosmetic industry. Therefore, the works to find bacteriocin-producing strains with broad-spectrum or specific antimicrobial compounds are still continued. In this study metabolites from LAB and Bacillus with anti-spectrum against putrefactive and skin-inflammatory microbes were prepared and concentrated to freezing-dried powder (BCMC). The antibiotic efficiency of BCMC in cosmetic formulation was evaluated consequently. The present results were as followings: 1.In vitro antagonism experiments, Bacillus circulans(BC-1) broth showed high activity against putrefactive and skin-inflammatory microbes. The antibiotic efficiency of BC-1 was highly increased through cell culture in RS medium. The possible antagonistic compounds were characterized as iturin A and its isoforms by HPLC analysis. These compounds showed stability against heat and pH treatment. 2.The BC-1 cell-free culture was subjected to methanol extraction followed lyophilization to make a concentrated powder named BCMC. The skin toxicity of BCMC was shown no detectable irritation by human patch test. 1%BCMC showed better antimicrobial activity than commercial antibiotic ingredients in well-agar-diffusion tests. 2%BCMC showed antimicrobial activity to all test putrefactive and skin-inflammatory microbes. 3.The cosmetic lotions added with 2.5%BCMC were prepared and the antibiotic activity was determined. The inoculated microbes (E. coli、 P. aeruginosa、 S. aureus、 P. acnes、 S.epidermidis及 S. pyogenes ) were totally inhibited during 7 days. The results showed good antibiotic effectiveness of BCMC in cosmetic formulation. 4.In storage test, the lotions with 2.5%BCMC and 1% Euxyl PE9010 were incubated at 4、25、40 and 500C, respectively. The plate counts of test lotions remained unchanged during one month. The results showed the stability of antibiotic effectiveness of BCMC under different storage temperatures. 5.One L. reuteri strain was found to transform glycerol into a potent broad-spectrum antimicrobial compound, reuterin, which inhibits the growth of fungi, gram-positive and gram-negative bacteria. However, the transform efficiency of reuterin was unstable and low. The antibiotic effectiveness in cosmetic products needs a further study.