关键词: 铁皮石斛, 花色苷, 提取, 抑菌活性

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