The active compounds in herb drugs are mainly secondary metabolites, which are greatly influenced by external conditions. Particularly, light intensity has a great influence on the photosynthesis and accumulation of s...The active compounds in herb drugs are mainly secondary metabolites, which are greatly influenced by external conditions. Particularly, light intensity has a great influence on the photosynthesis and accumulation of secondary metabolites. In this study, the light intensity was changed, and the influence of the light intensity on leaf photosynthetic characteristics, antioxidant enzyme activity and flavone contents of Lithocarpus litseifoliusp (Hance) Chun. was discussed. The results showed that (1) L. litseifolius is a typical heliophyte. As the light intensity decreased, the contents of chlorophyll a (Chl a), chlorophyll b (Chl b) and total chlorophyll (Chl a + b) all increased. However, the Chl a/b ratio gradually decreased. The daily variation of net photosynthetic rate changed from a double-peak curve under natural light to single-peak curve under 20% full light two shading nets. (2) As the light intensity decreased, the SOD and POD activities and the soluble proteins content decreased in the leaves. In contrast, the malondialdehyde content increased. (3) The flavone content was the highest in leaves at one shading nets 60% of full light, and the lowest occurred in leaves at two shading nets 20% of full light. A comprehensive analysis indicated that an appropriate shading could induce shade tolerance in the leaves of L. litseifolius, which promoted the accumulation of flavonoids. L. litseifolius should be planted in the lower position of sunny slope or the upper position of shady slope to increase the content of flavone in the leaves.展开更多
Five compounds were isolated from the precipitation of Lithocarpus litseifolius.On the basis of spectral data,they were identified as huazhongilexin(1),lithocarpic acid O(2),(24S^(*),25R^(*))-cycloartane-3β,24,25,26-...Five compounds were isolated from the precipitation of Lithocarpus litseifolius.On the basis of spectral data,they were identified as huazhongilexin(1),lithocarpic acid O(2),(24S^(*),25R^(*))-cycloartane-3β,24,25,26-tetrol(3),lithocarpic acid D(4),2,3,23-trihydroxy olean-12-en-28-oic acid(5).Compounds 1,3,5 were isolated from this plant for the first time,compound 2 was new and shown to be weak cytotoxic when tested against A549,HeLa,HepG2,and MCF-7 cell lines.展开更多
文摘The active compounds in herb drugs are mainly secondary metabolites, which are greatly influenced by external conditions. Particularly, light intensity has a great influence on the photosynthesis and accumulation of secondary metabolites. In this study, the light intensity was changed, and the influence of the light intensity on leaf photosynthetic characteristics, antioxidant enzyme activity and flavone contents of Lithocarpus litseifoliusp (Hance) Chun. was discussed. The results showed that (1) L. litseifolius is a typical heliophyte. As the light intensity decreased, the contents of chlorophyll a (Chl a), chlorophyll b (Chl b) and total chlorophyll (Chl a + b) all increased. However, the Chl a/b ratio gradually decreased. The daily variation of net photosynthetic rate changed from a double-peak curve under natural light to single-peak curve under 20% full light two shading nets. (2) As the light intensity decreased, the SOD and POD activities and the soluble proteins content decreased in the leaves. In contrast, the malondialdehyde content increased. (3) The flavone content was the highest in leaves at one shading nets 60% of full light, and the lowest occurred in leaves at two shading nets 20% of full light. A comprehensive analysis indicated that an appropriate shading could induce shade tolerance in the leaves of L. litseifolius, which promoted the accumulation of flavonoids. L. litseifolius should be planted in the lower position of sunny slope or the upper position of shady slope to increase the content of flavone in the leaves.
文摘Five compounds were isolated from the precipitation of Lithocarpus litseifolius.On the basis of spectral data,they were identified as huazhongilexin(1),lithocarpic acid O(2),(24S^(*),25R^(*))-cycloartane-3β,24,25,26-tetrol(3),lithocarpic acid D(4),2,3,23-trihydroxy olean-12-en-28-oic acid(5).Compounds 1,3,5 were isolated from this plant for the first time,compound 2 was new and shown to be weak cytotoxic when tested against A549,HeLa,HepG2,and MCF-7 cell lines.
