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排序方式: 共有559条查询结果,搜索用时 31 毫秒
1.
目的对毛茛科乌头属药用植物乌头Aconitum carmichaelii地上部分进行化学成分研究。方法乌头干燥的茎叶用甲醇回流提取,所得的浸膏用1.5%HCl溶解,醋酸乙酯萃取得总粗提取物。粗提物用各种柱色谱进行分离纯化,经光谱数据(~1H-NMR、~(13)C-NMR、MS)进行结构鉴定。结果从乌头地上部分分离得到15个化合物,分别鉴定为3-羧基-吲哚(1)、corchoionol C(2)、β-谷甾醇-3-O-β-D-葡萄糖苷-6′-棕榈酸酯(3)、松脂素(4)、(+)-N-formylnorglaucine(5)、oxoglaucidaline(6)、海罂粟碱(7)、(+)-cataline(8)、山柰酚-7-O-α-L-鼠李糖苷(9)、山柰酚-3-O-β-(2″-乙酰基)-半乳糖苷(10)、megastigmane(11)、山柰酚-7-O-α-L-阿拉伯糖苷(12)、山柰酚-3-O-β-D-吡喃木糖苷(13)、山柰酚-3-O-β-D-葡萄糖苷(14)、槲皮素-3-O-β-D-半乳糖苷(15)。结论化合物1~15均为首次从该植物的地上部分中分离得到,其中化合物1~3、5、6、8~15为首次从乌头中分离得到。 相似文献
2.
乌头植株再生体系的建立 总被引:4,自引:1,他引:4
目的 建立乌头高效再生系统,短期内获得大量优质种苗。方法 以试管苗叶片为外植体,在添加不同激素配比的培养基上培养。结果 培养基MS BAl.0mg/L KT0.5mg/L NAA0.2mg/L最适合于乌头叶片不定芽的分化;培养基MS BAl.5mg/L NAA0.1mg/L有利于芽的增殖;培养基MS BA0.5mg/L NAA0.1mg/L有利于芽的伸长;不加激素的1/2MS培养基有利于根的诱导。结论 采用组织培养方式可进行乌头的快速繁殖,使乌头种苗的工厂化生产成为可能。 相似文献
3.
Four new C19-diterpenoid alkaloids, hemaconitines A–D (1–4), were isolated from the roots of Aconitum hemsleyanum var. circinatum. Their structures were elucidated as 19R-hydroxyl-secoyunnaconitine (1), (3R)-hydroxyl-liwaconitine (2), 14-anisoyl-leucanthumsine E (3), and 19R -acetonyl-8-O-methyltalatisamine (4) by extensive spectroscopic analysis (IR, UV, HR-ESI-MS, 1D, and 2D NMR). 相似文献
4.
《Maturitas》2016
Current knowledge on the effects of nut consumption on human health has rapidly increased in recent years and it now appears that nuts may play a role in the prevention of chronic age-related diseases. Frequent nut consumption has been associated with better metabolic status, decreased body weight as well as lower body weight gain over time and thus reduce the risk of obesity. The effect of nuts on glucose metabolism, blood lipids, and blood pressure is still controversial. However, significant decreased cardiovascular risk has been reported in a number of observational and clinical intervention studies. Thus, findings from cohort studies show that increased nut consumption is associated with a reduced risk of cardiovascular disease and mortality (especially that due to cardiovascular-related causes). Similarly, nut consumption has been also associated with reduced risk of certain cancers, such as colorectal, endometrial, and pancreatic neoplasms. Evidence regarding nut consumption and neurological or psychiatric disorders is scarce, but a number of studies suggest significant protective effects against depression, mild cognitive disorders and Alzheimer’s disease. The underlying mechanisms appear to include antioxidant and anti-inflammatory actions, particularly related to their mono- and polyunsaturated fatty acids (MUFA and PUFA, as well as vitamin and polyphenol content). MUFA have been demonstrated to improve pancreatic beta-cell function and regulation of postprandial glycemia and insulin sensitivity. PUFA may act on the central nervous system protecting neuronal and cell-signaling function and maintenance. The fiber and mineral content of nuts may also confer health benefits. Nuts therefore show promise as useful adjuvants to prevent, delay or ameliorate a number of chronic conditions in older people. Their association with decreased mortality suggests a potential in reducing disease burden, including cardiovascular disease, cancer, and cognitive impairments. 相似文献
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6.
Wild-growing mushrooms could be a potential source of mineral elements The aim of this study was to analyze the mineral composition of 18 species of wild-growing mushrooms collected in a natural park from the Spanish southeast (province of Granada). Ca, Mg, K, Na, Fe, Cu and Zn, were determined by flame atomic absorption spectroscopy and P was analyzed colorimetrically by the vanadomolybdate procedure; the accuracy of methods was assessed by the use of certified reference materials. The contribution of mushrooms consumption to the mineral daily recommended intakes was calculated. Although large variations were observed between species, the most abundant mineral elements in the analyzed mushrooms were K and P, with average contents of 29.3 ± 8.1 and 8.60 ± 4.8 g/kg dry matter (dm), respectively. Low Na concentrations were observed (26.5–579 mg/kg dm), with the only exception of Amanita ovoidea, and high Fe values, exceeding in some cases 1000 mg/kg dm (such as in Lactarius deliciosus and Morchella conica). Mushrooms may be significant contributors of K and P in the human diet and also good sources of trace elements, especially Cu and Fe, providing negligible quantities of Na. Strong correlations were observed for Ca/Mg and Cu/Zn contents in the mushrooms analyzed. 相似文献
7.
Cannabidiol (CBD) exhibits significant efficacy in mental and inflammatory diseases. Several studies have recently reported on the rapid antidepressant-like effects of CBD, suggesting that CBD is a potential anti-depressant or anti-stress drug. However, CBD is mainly administered orally or by inhalation with poor bioavailability, resulting in high costs. We aim to explore the efficacy of long-term periodic administration of CBD in chronic mild stress (CMS) via two routes and its pharmacokinetics. We treated ICR mice with CBD administered orally and intravenously and then determined the kinetic constants. A single bolus intravenous injection of CBD resulted in a half-life of 3.9 h, mean residence time of 3.3 h, and oral bioavailability of about 8.6%. The antidepressant-like effects of periodically administered CBD on the chronic mild stress mouse model are evaluated. Results demonstrated that such treatment at a high dose of 100 mg/kg CBD (p.o.) or a low dose of 10 mg/kg CBD (i.v.), elicited significant antidepressant-like behavioral effects in forced swim test, following increased mRNA expression of brain-derived neurotrophic factor (BDNF) and synaptophysin in the prefrontal cortex and the hippocampus. Our findings are expected to provide a reference for the development of intravenous antidepressant formulations of CBD. 相似文献
8.
9.
Juan He Man-Si Yang Wen-Xiang Wang Zheng-Hui Li Waill Ahmed Mohamed Elkhateeb Ting-Chi Wen Hong-Lian Ai Tao Feng 《RSC advances》2018,9(1):128
A bioguided separation on the cultures of the potato endophytic fungus Bipolaris eleusines led to the isolation of two anti-phytopathogenic (Alternaria solani) sesquiterpenoid-xanthone adducts, namely bipolins I and J (1 and 2). Their structures were established via extensive spectroscopic analysis. Compounds 1 and 2 exhibit potent inhibitory activity against A. solani with MIC values of 8 and 16 μg mL−1, respectively.Two sativene sesquiterpenoid-xanthone adducts from potato endophytic fungus Bipolaris eleusines 相似文献
10.
Fengcai ZOU Xin YU Yan YANG Shuang HU Hua CHANG Jianfa YANG Gang DUAN 《Iranian Journal of Parasitology》2015,10(4):648-651