Inhibitory effects of botanical extracts on the growth, biofilm and lipase activity of acne-causing bacteria

• Main Authors: Yau Rong Liing, 嶺瑤蓉
• Other Authors: Po Jung Tsai
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/98062724798573061403

碩士 === 國立臺灣師範大學 === 人類發展與家庭學系 === 99 === Acne vulgaris is a chronic disorder of the pilosebaceous follicles of the skin. Acne-causing bacteria, such as Propionibacterium acnes and Staphylococcus epidermidis, play an important role in the pathogenesis of acne vulgaris. Both bacteria resided within the follicles grow as a biofilm and hydrolyzed triglyceride to free fatty acids by bacterial lipase has been proposed as a major factor in the pathogenesis of acne vulgaris. ROS, and especially superoxide anions, were rapidly produced by keratinocytes upon stimulation by P. acnes surface proteins. In addition, superoxide anions were generated by P. acnes stimulated keratinocytes and involved in the development of acne inflammatory lesions. The aim of this study was to investigate inhibitory effects of various botanical extracts on growth, biofilm formation, and extracellular lipase activity of acne-causing bacteria and their anti-oxidation properties. Aqueous, methanolic, ethanolic and EA extract of rosemary were analyzed and quantified by HPLC. The antimicrobial activity of extracts was assessed by determining of minimum inhibitory concentration (MIC) values obtained by a modified microdilution broth method. Results showed that ethanolic, methanolic, ethyl-acetate and aqueous extracts of rosemary, sage, verbena, green tea and black tea significantly inhibited the growth of acne-causing bacteria, including P. acnes and S. epidermidis. Aqueous extract of verbena significantly inhibited the growth of P. acnes. We also tested the inhibitory activity of botanical extracts on the biofilm-forming ability of P. acnes in a microtiter plate model. In a preliminary experiment, we determined the optimal conditions for P. acnes biofilm formation. A mature biofilm (i.e. a biofilm in which the biomass does not significantly increase any further) was established following 48 hr incubation. Following 16 hr incubation, ethanolic, methanolic, ethyl-acetate and aqueous extracts of rosemary, sage, verbena, green tea, and black tea significantly prevented biofilm formation of P. acnes. In addition, ethanolic, methanolic and aqueous extracts of sage and green tea could remove established mature biofilm of P. acne. Furthermore, we conducted experiments to investigate the inhibitory effect of botanical extracts on crude lipase activity of acne-causing bacteria. Results showed that ethanolic, methanolic, ethyl-acetate and aqueous extracts of rosemary, sage, verbena, green tea and black tea significantly inhibited lipolytic activity of crude lipase purified from P. acnes and S. epidermidis. In the present study, the antioxidant activity of botanical extracts was determined by the scavenging activities of 2, 2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide, superoxide and hydroxyl radical . We also evaluated the total phenolic contents of botanical extracts. The potent radical scavenging effects were observed in ethanolic, methanolic, ethyl-acetate and aqueous extracts of rosemary, sage, verbena, green tea, and black tea. Besides aqueous extract of rosemary, rosmarinic acid, carnosol and carnosic acid were determined and quantified by HPLC in the methanolic, ethanolic and EA extract of rosemary. In conclusion, extracts of rosemary, sage, verbena, green tea, and black tea had potent inhibitory effects on the growth, lipolytic activity and biofilm formation of acne-causing bacteria and possessed excellent anti-oxidative properties.These data suggested that extracts of rosemary, sage, verbena, green tea, and black tea may be potentially therapeutic agents for the treatment of acne vulgaris.