唐古特白刺中黄酮类化合物正交提取工艺与体外抗菌活性研究

Orthogonal extracting process and in vitro antibacterial activity of flavonoids from Nitraia tangutorum Bor.

用索氏回流法正交提取唐古特白刺中的黄酮类化合物,用黄酮类化合物最大吸光度(吸收波长510 nm)对提取物进行可见光谱检测,测定黄酮类化合物的含量。以芦丁标准品做对照,对比选取最佳提取工艺;并对两种供试菌进行体外最小抑制浓度(MIC)测定。结果表明,乙醇浓度、乙醇用量、回流时间、超声功率、超声时间的不同对唐古特白刺中黄酮的提取均有影响。其最佳工艺参数为:乙醇浓度65%、乙醇体积250 mL(唐古特白刺10.0 g)、回流时间1 h、超声功率70%、超声时间40 min;对大肠埃希氏杆菌、金黄色葡萄球菌的MIC分别为0.35 mg/mL和0.50 mg/mL。

Soxhlet reflux method was used to extract flavonoids from Nitraia tangutorum Bor.and the extracting process was optimized by orthogonal test with rutin as an indicator.Then the contents of total flavonoids were measured at the maximum absorption wavelength of 510 nm with spectrometry.The minimal inhibitory concentration（MIC） of the flavonoids was measured by means of bacteriostasis tests in vitro on two kinds of bacteria.The results showed that ethanol concentration,ethanol volume,reflux time,ultrasonic frequency and ultrasonic time could all impact the extracting of the the flavonoids.The optimal process was as follows： 250 mL ethanol at 65%,reflux for 1 h,ultrasonic frequency of 70% and ultrasonic extracting for 40 min.MIC of the flavonoids against Escherichia coli and Staphylococcus aureus was 0.35 and 0.50 mg/mL,respectively.