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Seed characteristics and the lipid and fatty-acid compositions were determined for the new cotton varieties ASh-25, Omad, 9771-I, Termez-43, and Bukhara-6.  相似文献   

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Three crystalline compounds, rhamnetin(1), rhamnocitrin(4), and kaempferol(6) were isolated from the hot methanol extract of leaves of Rhamnus formosana Matsum.  相似文献   

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从槲树叶Quercus dentata Thunb中分离纯化得到五种酚性成分. 通过理化性质分析和光谱解析等手段确定其化学结构分别为: 2-新橙皮糖基-2,6-二羟基苯甲酸苯甲酯(1), 龙胆酸5-O-(6-O-没食子酰基)--D-吡喃葡萄糖苷(2), 3,5,7-三羟基色原酮-3-O--D-吡喃葡萄糖苷(3), 没食子酸(4), 儿茶素(5), 其中化合物13为新化合物.  相似文献   

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Eleven chemical constituents were isolated from the ethyl acetate soluble fraction of the aerial part of Rosa laevigata Michx. These compounds include the Henze's ketol (16), diethyl malate (17), three γ-lactones (18-20), loliolide (21), p-coumaric acid (22), 6,7-dimethoxycoumarin (23) and three flavonoids (24-26). The new compounds 19 and 20 were determined to be the cis- and trans-isomers of ethyl 2-benzyl-3-hydroxy-5-oxo-3-furancarboxylate.  相似文献   

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Bioassay‐guided fractionation of the active AcOEt‐soluble layer from the whole plant of Amischotolype hispida resulted in the isolation of four new compounds, i.e., amisbenzoic acid ( 1 ), one butenolide derivative, amisnolide ( 2 ), one chlorin analog, amisphytin ( 3 ), one lignan, amislignol ( 4 ), and one metabolite isolated for the first time from nature, (?)‐glaberide I ( 5 ), along with 20 known compounds, 6 – 25 . Their structures were elucidated on the basis of UV, IR, 1D‐ and 2D‐NMR (1H,1H‐COSY, DEPT, HSQC, HMBC), as well as HR‐ESI‐MS, analyses. Among these isolates, palmitic acid ( 13 ) showed an antimycobacterial activity with an MIC value of 20.0 μg/ml against Mycobacterium tuberculosis H37Rv.  相似文献   

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建立了微波消解-电感耦合等离子体质谱法,测定香菇、金针菇、白玉菇、杏鲍菇和茶树菇5种食用菌中必需微量元素(Mg、Ca、V、Cr、Mn、Fe、Co、Ni、Cu、Zn、Se、Sr)和有害元素(As、Cd、Pb)的含量。以微量元素为指标,评价5种食用菌的营养价值和食用安全性。结果表明,5种食用菌均含有丰富Mg、Ca、Cr、Mn、Fe、Cu、Zn,及少量V、Co、Ni、Se、Sr、As、Cd和Pb,且重金属As、Cd和Pb含量均低于国家标准(GB7096-2003)中关于食用菌规定的总量,食用安全。统计回归分析表明,香菇与其它4种食用菌同属真菌,因此微量元素含量相关系数R0.6,但P值均大于0.05,说明微量元素含量因科属的不同而有较大差异,但影响不显著。  相似文献   

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Three new monosialo-gangliosides, CEG-3 (3), CEG-4 (4), and CEG-5 (5), were obtained, together with two known gangliosides, SJG-1 (1) and CG-1 (2), from the lipid fraction of the chloroform/methanol extract of the sea cucumber Cucumaria echinata. The structures of the new gangliosides were determined on the basis of chemical and spectroscopic evidence to be 1-O-[4-O-acetyl-alpha-L-fucopyranosyl-(1-->11)-(N-glycolyl-alpha-D-neuraminosyl)-(2-->6)-beta-D-glucopyranosyl]-ceramide (3) and 1-O-[alpha-L-fucopyranosyl-(1-->11)-(N-glycolyl-alpha-D-neuraminosyl)-(2-->6)-beta-D-glucopyranosyl]-ceramide (4, 5). The ceramide moieties of each compound were composed of heterogeneous sphingosine or phytosphingosine bases, and 2-hydroxy or nonhydroxylated fatty acid units. These gangliosides showed neuritogenic activity toward the rat pheochromocytoma cell line PC-12 in the presence of nerve growth factor.  相似文献   

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