NOVEL NATURAL ANTIMICROBIAL SUBSTANCE ISOLATED FROM THE STALK AND LEAF OF HOVENIA DULCIS THUNB AND ISOLATING METHOD THEREOF

摘要

PURPOSE: A novel natural antimicrobial substance isolated from the stalk and leaf of Hovenia dulcis Thunb and an isolating method thereof are provided. Therefore, the novel natural antimicrobial substance, hovenidine B6, having pyridine structure can be found. CONSTITUTION: The novel natural antimicrobial substance, hovenidine B6 is isolated from the stalk and leaf of Hovenia dulcis Thunb by the steps of: heat-extracting the stalk and leaf of Hovenia dulcis Thunb; centrifuging the extract and freeze-drying the supernatant to obtain the extract powder; concentrating the methanol filtrate under reduced pressure to obtain methanol extract; adding a weak alkali buffer and ethylacetate into the methanol extract to divide a liquid fraction and an ethylacetate neutral fraction, and adding ethylacetate into the liquid fraction to obtain ethylacetate acid fraction; subjecting the above fractions to silica gel adsorption column chromatography using ethylacetate-methanol solution to obtain an active fraction; subjecting the active fraction to gel filtration chromatography using Sephadex LH-20 column; and subjecting the purified fraction to reverse HPLC using methanol-water solvent to isolate hovenidine B6.