Abstract: Taking Dendrobium candidum in Longling County of Yunnan Province as experimental material, this study obtained anthocyanins with solvent-extraction method. The effects of ethanol volume fraction, material-liquid ratio, extraction temperature, pH, extraction time on the extraction rate of anthocyanins were studied by single fator experiment; and the best extraction technology condition was obtained through technology optimization by orthogonality experimental method. Besides, bacteriostasic activities of anthocyanins from Dendrobium candidum inhibiting Escherichia coli, Staphyloccocus aureus, Bacillus subtilis were also studied. Results showed that the optimal condition were as following: ethanol 60%, material-liquid ratio 1 g∶20 mL, extraction temperature 4℃, pH 3, extraction time 120 min, twice extraction time, and the total anthocyanins yield 3.12 mg/g FW. The minimum inhibitory mass concentration(MIC) on Escherichia coli, Staphyloccocus aureus, Bacillus subtilis were 9.75 mg/L, 4.88 mg/L and 1.22 mg/L, respectively. And the minimum bactericidal concentration(MBC) were 9.75 mg/L, 4.88 mg/L, 2.44 mg/L, respectively.

Key words: Dendrobium candidum, anthocyanin, extraction, anti-microbial activity

摘要： 以云南龙陵铁皮石斛为试验材料，用溶剂浸提法提取铁皮石斛花色苷。通过单因素试验考察乙醇体积分数、料液比、提取温度、pH、提取时间对铁皮石斛花色苷提取率的影响，以正交试验进行工艺优化得到最佳提取工艺条件。并考察铁皮石斛花色苷对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌的抑制作用。结果表明，溶剂浸提法提取铁皮石斛花色苷的最佳工艺条件为：60%乙醇、料液比为1 g:20 mL、提取温度40℃、pH 3、提取时间120 min、提取次数为2次，花色苷含量为3.12 mg/g FW。其对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌的最低抑菌质量浓度分别为9.75 mg/L、4.88 mg/L和1.22 mg/L，最低杀菌质量浓度分别为9.75 mg/L、4.88 mg/L、2.44 mg/L。

关键词: 铁皮石斛, 花色苷, 提取, 抑菌活性