Joung Hee, Kwon Dong-Yeul, Choi Jang-Gi, Shin Dong-Young, Chun Soon-Sil, Yu Young-Beob, Shin Dong-Won
Department of Oriental Medicine Resources, College of Bio Industry Science, Sunchon National University, Sunchon, Jeonnam, Republic of Korea.
J Nat Med. 2010 Apr;64(2):212-5. doi: 10.1007/s11418-010-0388-7. Epub 2010 Jan 30.
Smallanthus sonchifolius (yacon) is a perennial plant mostly cultivated in South America, primarily for use of the tubers as a food crop and the leaves as fodder for livestock. The antibacterial activities of the methanol extract of yacon leaves (S. sonchifolius) and its n-hexane, ethyl acetate, n-butanol and water fractions were evaluated against 6 strains of methicillin-resistant Staphylococcus aureus (MRSA) and 1 standard methicillin-susceptible S. aureus (MSSA) strain by using the disc diffusion method and minimal inhibitory concentrations (MICs) assay in the presence and absence of light. No activity was detected when the two methods were performed without light; however, under illumination at 4000 lux, the n-hexane fraction of yacon (HFY) had a MIC of 15.6 microg/ml. HFYL, prepared by exposure of HFY to 4000 lux for 18 h, was more effective than HFY in terms of antimicrobial activity against the 6 MRSA strains and 1 standard MSSA strain. HFYL mixed with ampicillin or oxacillin showed a synergistic effect with all fractional inhibitory concentrations values being below 0.5. The present study demonstrates the enhancement and antimicrobial activity of yacon leaves against MRSA in the presence of light.
雪莲果是一种多年生植物，主要生长在南美洲，其块茎作为粮食作物，叶子用作牲畜饲料。采用纸片扩散法和最低抑菌浓度（MIC）测定法，在有光和无光条件下，评估了雪莲果叶甲醇提取物及其正己烷、乙酸乙酯、正丁醇和水相部分对6株耐甲氧西林金黄色葡萄球菌（MRSA）和1株甲氧西林敏感金黄色葡萄球菌（MSSA）标准菌株的抗菌活性。在无光条件下进行这两种方法时未检测到活性；然而，在4000勒克斯光照下，雪莲果正己烷相部分（HFY）的MIC为15.6微克/毫升。将HFY置于4000勒克斯光照下18小时制备的HFYL，对6株MRSA菌株和1株MSSA标准菌株的抗菌活性比HFY更强。HFYL与氨苄西林或苯唑西林混合显示出协同效应，所有分级抑菌浓度值均低于0.5。本研究证明了在光照条件下雪莲果叶对MRSA的抗菌活性增强。
