Abstract: Polysaccharides of Viola diffusa and V. principis were extracted by ethanol precipitation and antimicrobial and antioxidant tests were carried out respectively. The results showed that the extraction rate of V. diffusa and V. principis polysaccharide was 7.0% and 8.3% respectively. The antimicrobial and antioxidant activities of polysaccharides extracted by ethanol precipitation with different multiple volumes were different. Antibacterial experiment indicated that the inhibition zone of V. diffusa polysaccharide to Escherichia coli and Bacillus subtilis reached 8.46 mm and 8.59 mm, while those of V. principis were 9.13 mm. However, neither of the two violets showed inhibitory activity against Aspergillus niger and Saccharomyces cerevisiae. The antioxidant evaluation suggested that antioxidant activity of polysaccharide of V. diffusa was 243.64 U·mL-1, while the antioxidant activity of V. principis was 411.78 U·mL-1. Thus V. principis was significantly stronger than V. diffusa in antimicrobial and antioxidant activities (P<0.01). In general, there was a certain anti-oxidative activity of polysaccharide of V. diffusa and V. principis, therefore, both of them could be used as a resource of medicinal and edible plant for development and utilization.

Key words: Viola diffusa, Viola principis, polysaccharides, antibacterial, antioxidant activity

摘要： 利用乙醇沉淀法提取蔓茎堇菜Viola diffusa和柔毛堇菜V. principis多糖并分别进行抑菌及抗氧化试验。结果表明，蔓茎堇菜和柔毛堇菜多糖提取率分别为7.0%和8.3%。不同倍数体积无水乙醇沉淀提取的多糖抑菌和抗氧化能力不同。抑菌效果显示，蔓茎堇菜多糖对大肠杆菌和枯草芽孢杆菌的抑菌圈分别可达8.46 mm和8.59 mm，柔毛堇菜对大肠杆菌和枯草芽孢杆菌的抑菌圈均可达9.13 mm，但两种堇菜多糖对黑曲霉和啤酒酵母未呈现抑制活性；抗氧化研究发现，蔓茎堇菜多糖抗氧化活性为243.64 U·mL-1，柔毛堇菜多糖抗氧化活性为411.78 U·mL-1。由此可见，无论是抑菌还是抗氧化活性方面，柔毛堇菜极显著优于蔓茎堇菜(P <0.01)。蔓茎堇菜和柔毛堇菜多糖都具有一定的抑菌抗氧化活性，均可作为食药两用植物资源进行开发利用。

关键词: 蔓茎堇菜, 柔毛堇菜, 多糖, 抗菌, 抗氧化活性