樟树叶中木脂素化合物的分离鉴定及其抑菌活性

Isolation and Identification of Lignans from Cinnamomum camphora and Its Antibacterial Activity

为了分离与鉴定樟树叶95%乙醇提取物中正丁醇层木脂素类物质并考察其抑菌活性,分别采用大孔树脂、硅胶、Sephadex LH-20,ODS等柱色谱技术进行分离与纯化;运用现代波谱学方法,包括紫外色谱、红外光谱、质谱、核磁共振等进行结构鉴定。通过滤纸片琼脂扩散法和二倍稀释法测定樟树叶木脂素对4种供试菌的抑菌活性,结果表明:从樟树叶中分离鉴定了2种木脂素化合物,分别为(+)松脂素-β-D-葡萄糖苷(1)、芝麻素(2),均是首次从樟树叶中分离得到。抑菌试验表明:松脂素-β-D-葡萄糖苷和芝麻素对食品中常见的4种供试菌具有不同程度的抑制作用,对细菌的抑制作用优于真菌。

To isolate and identify the lignans in the 95% ethanol extracts from the leaves of Cinnamomum camphora and research the antibacterial activity of lignans. The compounds were purified by AB-8 macroporous resin, silica gel, Sephadex LH-20, ODS column chromatography. The structures of the compounds were identified on the basis of chemical methods （Ecgrine and Labet reaction） and spectral methods（UV, IR, MS , H-NMR, C-NMR）. The agar disc diffusion method was used to determine the diameter of inhibition zone （DIZ）. The dilution broth method measured the minimum inhibitory concentration （MIC） and minimum bacterial concentration （MBC）. Four compounds are identified as （＋） pinoresinol-β-D-gluciside （1）, sesamin （2）. Compounds 1, 2 are reported in the leaves of this species for the first time. The compounds can inhibit gram negative bacteria （E. coli） as well as gram positive bacteria （S. aureus）. The average of DIZ values of E.coli, S.aureus are 10.55, 12.44 mm, respectively. The MIC values of E. coli, S. aureus are 31.25- 62.5 μg/mL. The MBC values of E. coli, S. aureus are 62.5-125 μg/mL. The Gram- negative microorganisms are slight- ly more sensitive to lignans when compared to Gram positive. The lignans is suitable as a natural preservative to inhibit the growth of food-spoilage, extending the shelf life of food.