《生药学教学课件》12-裸子植物

生木质部大多为管胞,极少有导层,次生木质部大多为管胞,极少有导管;韧皮部中有筛胞而无伴胞。管;韧皮部中有筛胞而无伴胞。??化学成分: 化学成分: 1. 1. 黄酮类黄酮类; ; 2. 2. 生物碱类。生物碱类。银杏叶银杏叶 Ginkgo Folium Ginkgo Folium 【【来源来源】】为银杏科植物为银杏科植物银杏银杏 Ginkgo biloba Ginkgo biloba L. L. 的的干燥叶。干燥叶。【【性状鉴别性状鉴别】】【【显微鉴别显微鉴别】】上表皮气孔下表皮韧皮部木质部草酸钙簇晶【【化学成分化学成分】】 1 1、黄酮类、黄酮类(flavonoids) (flavonoids) ?黄酮醇及黄酮醇苷类(flavonols and flavonol glycosides) ?双黄酮类(biflavones) ?原花色素类( proanthocyanidins ) O HOOHO OH R 2 OR 1 kaemperol R 1 = H R 2 = H quercetin R1 = H R2 = OH in R1 = H R2 = OMe 3-O -[6- O-(?-L-rhamnosyl )-?-D-glucosyl]in 3-O -[2- O-(?-D-glucosyl )-?-L-rhamnosyl]quercetin 3-O -[6- O-(?-L-rhamnosyl ) - ?-D-glucosyl]kaempferol Main flavonoids occurring in Ginkgo biloba O HO OH O OH OH O O H 3C HOHOOO HOOH OH O C C OH H HCO C36H36O18 MW=756