芦荟抗菌作用与蒽醌化合物的关系

目的 :分析芦荟抗菌作用与蒽醌化合物含量的关系 ,比较芦荟大黄素和芦荟苷的抗菌作用 ,探讨糖基取代结构对芦荟苷抗菌活性的影响。方法 :利用琼脂扩散法分析皂质芦荟叶皮提取物、芦荟大黄素和芦荟苷对 3种革兰氏阴性菌、2种革兰氏阳性菌的抑菌活性 ,利用扫描电镜技术分析了芦荟苷对大肠杆菌的作用。结果 :芦荟的抗菌作用与蒽醌化合物的含量呈正相关性。芦荟苷 (1g·L^-1)具有较强的抗菌活性 抑菌直径大于 (7.1±0.15)mm] ,对革兰氏阳性菌的抗性高于革兰氏阴性菌。芦荟大黄素的抗菌活性较弱。芦荟苷能够改变细胞的形态 ,破坏细胞结构。结论 :蒽醌化合物是芦荟中的抗菌成分 ,芦荟苷是主要抗菌有效成分之一 ,葡萄糖基取代结构增强了其侵入细胞外被和杀菌的能力。

Relationship Between Antibacterial Activity of Aloe and Its Anthaquinone Compounds

Objective: To investigate the relationship between the antibacterial activity of aloe and its contents of anthaquinone comp ounds, measure and compale antibacterial activities of aloin and aloe-emodin, a nd analyse the effect of glycoside on the antibacterial activity of aloin. Method: The antibacterial activities of the extracts from the o uter leaf of Aloe saponaria Haw, aloin and aloe-emodin against three Gram-nega tive and two Gram-positive bacteria were investigated with the method of agar d iffusion. The antibacterial effect of aloin on E. coli was further studied with scanning electron microscopy. Result: The antibacterial ac tivities of aloe showed to be dependent on the dose of anthraquinone, aloin (1 g ·L ^{-1) exhibited higher antibacterial activity inhibition diameter>(7.1±0.15) mm] than Aloe-emodin (inhibition diameter<5.0 mm), and aloin changed the morphology of E.coli and damaged the outer cell structrue. Concl usion: Anthraquinone compounds are the active antibacterial component s in aloe and aloin is the main active compound. The glycoside makes it easy for aloin to invade cells and enhances its activity.}