Joung Dae-Ki, Joung Hee, Yang DA-Wun, Kwon Dong-Yeul, Choi Jang-Gi, Woo Seo, Shin Dong-Young, Kweon Oh-Hyun, Kweon Kee-Tae, Shin Dong-Won
Department of Oriental Medicine Resources, College of Bio Industry Science, Sunchon National University, Sunchon, Jeonnam 540-742;
Exp Ther Med. 2012 Apr;3(4):608-612. doi: 10.3892/etm.2012.459. Epub 2012 Jan 25.
Methicillin-resistant Staphylococcus aureus (MRSA) is a bacterium responsible for a number of infections in humans that are difficult to treat, and as a result, is a substantial contributor to morbidity and mortality. In the present study, in search of natural products capable of inhibiting this multidrug-resistant bacterium, we investigated the antimicrobial activity of rhein isolated from Rheum palmatum L. (Polygonaceae) against 16 different strains of the bacterium. New antimicrobial activity was found using the paper disc diffusion method [minimal inhibitory concentrations (MICs)], MTT test and checkerboard dilution test. Against the 16 strains, the disc diffusion test was in the range of 20-29 mm and the MICs of rhein were in the range of 7.8-31.25 μg/ml. From these results we performed the checkerboard test to determine the synergism of rhein in combination with ampicillin (AM) or oxacillin (OX) against all strains. The combined activity of rhein and the two antimicrobial agents (AM and OX) against all strains resulted in a fractional inhibitory concentration index ranging from 0.28-1 and from 0.18-1, respectively. The effect of rhein with AM and OX was found to be synergistic or partially synergistic. We found that rhein reduced the MICs of AM and OX. Rhein in combination with AM or OX could lead to the development of new combinations of antibiotics against MRSA infection.
耐甲氧西林金黄色葡萄球菌（MRSA）是一种可导致人类多种难以治疗的感染的细菌，因此，它是导致发病和死亡的一个重要因素。在本研究中，为了寻找能够抑制这种多重耐药细菌的天然产物，我们研究了从掌叶大黄（蓼科）中分离出的大黄酸对16种不同菌株的抗菌活性。采用纸片扩散法[最低抑菌浓度（MIC）]、MTT试验和棋盘稀释试验发现了新的抗菌活性。对于这16种菌株，纸片扩散试验的抑菌圈直径在20 - 29毫米之间，大黄酸的MIC在7.8 - 31.25微克/毫升之间。根据这些结果，我们进行了棋盘试验，以确定大黄酸与氨苄西林（AM）或苯唑西林（OX）联合使用对所有菌株的协同作用。大黄酸与这两种抗菌剂（AM和OX）联合使用对所有菌株的活性导致分级抑菌浓度指数分别在0.28 - 1和0.18 - 1之间。发现大黄酸与AM和OX的作用是协同或部分协同的。我们发现大黄酸降低了AM和OX的MIC。大黄酸与AM或OX联合使用可能会产生针对MRSA感染的新抗生素组合。
