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61.
Elena V. Popova Eun-Jung Lee Chun-Hua Wu Eun-Joo Hahn Kee-Yoeup Paek 《Plant Cell, Tissue and Organ Culture》2009,97(3):337-343
Two-years-old Ginkgo biloba cell culture initiated from cotyledonary explants was cryopreserved by a simple desiccation method. Preliminary incubation
of callus clumps on MS preculture medium supplemented with 100 g l−1 sucrose and 2 mg l−1 ABA for 7 and 14 days resulted in accumulation of endogenous soluble sugars and was essential for cell culture post-cryopreservation
survival. The optimal time for the preculture on sucrose-and-ABA containing medium was found to be 14 days. The sufficient
desiccation duration was determined as 150 min. FCM profiles of calli maintained for 2 years remained stable and were not
affected by cryopreservation. 相似文献
62.
银杏内生菌Chaetomium globosum ZY-22次生代谢产物分离鉴定 总被引:2,自引:0,他引:2
采用柱层析方法从银杏叶内生真菌Chaetomium globosum ZY-22的培养菌丝体提取物中分离得到脑苷脂B(1)、脑苷脂C(2)、尿囊素(3)、9(11)-去氢麦角甾醇过氧化物(4)以及4,6,8,22-四烯-3-酮-麦角甾烷(5)和球毛壳甲素(6)共6个次生代谢物;经波谱分析确定了6个化合物的结构,其中脑苷脂B、脑苷脂C和尿囊素是首次从内生真菌中得到;海虾致死试验结果显示,化合物1~6在10 μg/mL浓度下对丰年虾的致死率分别为1.6%、4.2%、7.4%、16.9%、12.8%、83.6%、表明球毛壳甲素对海虾表现出很强的毒性作用. 相似文献
63.
A comparison of testing methods for constituents of Ginkgo biloba was performed as part of the process for determining which of the many available analytical methods was most appropriate for inclusion in the American Herbal Pharmacopoeia (AHP). Three primary methods were reviewed: those adopted by the European Pharmacopoeia, the National Science Foundation-Institute for Nutraceutical Advancement (NSF-INA) and the United States Pharmacopeia. Methods were compared by evaluating sample preparation and hydrolysis, precision and methods of total flavonol glycoside calculation by two independent laboratories. The AHP adopted the method of NSF-INA for inclusion in the AHP monograph owing to observed superiority of this method in terms of precision, glycoside calculation, ease of sample preparation and chromatographic parameters. 相似文献
64.
Ginkgolides are potent blockers of the glycine receptor Cl- channel (GlyR) pore. We sought to identify their binding sites by comparing the effects of ginkgolides A, B and C and bilobalide on alpha1, alpha2, alpha1beta and alpha2beta GlyRs. Bilobalide sensitivity was drastically reduced by incorporation of the beta subunit. In contrast, the sensitivities to ginkgolides B and C were enhanced by beta subunit expression. However, ginkgolide A sensitivity was increased in the alpha2beta GlyR relative to the alpha2 GlyR but not in the alpha1beta GlyR relative to the alpha1 GlyR. We hypothesised that the subunit-specific differences were mediated by residue differences at the second transmembrane domain 2' and 6' pore-lining positions. The increased ginkgolide A sensitivity of the alpha2beta GlyR was transferred to the alpha1beta GlyR by the G2'A (alpha1 to alpha2 subunit) substitution. In addition, the alpha1 subunit T6'F mutation abolished inhibition by all ginkgolides. As the ginkgolides share closely related structures, their molecular interactions with pore-lining residues were amenable to mutant cycle analysis. This identified an interaction between the variable R2 position of the ginkgolides and the 2' residues of both alpha1 and beta subunits. These findings provide strong evidence for ginkgolides binding at the 2' pore-lining position. 相似文献
65.
Evidence-based drug--herbal interactions 总被引:2,自引:0,他引:2
Due to the growing use of herbals and other dietary supplements healthcare providers and consumers need to know whether problems might arise from using these preparations in combination with conventional drugs. However, the evidence of interactions between natural products and drugs is based on known or suspected pharmacologic activity, data derived from in vitro or animal studies, or isolated case reports that frequently lack pertinent information. The usefulness of such information is questionable. More recently an increasing number of documented case reports, in vivo studies, and clinical trials have evaluated herbal-drug interactions. Results have sometimes been contradictory and more research is needed. Since there is a lack of rigorous studies that can establish the clinical significance of herb-drug interactions, an evidence-based evaluation of the current literature concerning commonly used herbal-drug interactions, as well as other dietary supplements, was conducted. 相似文献
66.
目的:研究一种以银杏叶、牛蒡提取物为主成分的发酵食品(GBF)对小鼠衰老指标的影响。方法:以D-半乳糖造衰老模型,以每只每天0.5ml剂量的GBF对小鼠灌胃,以不喂GBF的衰老模型小鼠为对照,以正常饲养的小鼠为空白对照(CK),42d后研究其对衰老相关指标组织单胺氧化酶、丙二醛含量、羟脯氨酸含量和腹腔巨噬细胞吞噬活性的影响。结果:喂食GBF的小鼠肝,脑组织中单胺氧化酶的活性比对照降低了36.7%和25.1%,丙二醛含量比对照降低了19%和44.6%。差异达到统计学显著水平(p<0.05);而皮肤组织中羟脯氨酸含量和巨噬细胞吞噬活性分别高于对照28.6%和63.2%,显著高于对照(p<0.05)。结论:GBF具有显著抗衰老活性。 相似文献
67.
3-Nitropropionic acid (3-NP), an irreversible inhibitor of succinate dehydrogenase enzyme (SDH), induces neurodegeneration similar to that observed in Huntington’s disease (HD). Reduction of prepulse inhibition (PPI) of acoustic startle response, locomotor hypoactivity, bilateral striatal lesions as well as brain oxidative stress are major features of HD. The present study was designed to investigate neuroprotective effect of Ginkgo biloba extract (EGb 761) on 3-NP induced neurobehavioral changes and striatal lesions.Rats administered 3-NP (20 mg/kg, s.c.) for five consecutive days exhibited PPI deficits and locomotor hypoactivity whereas, pretreatment of animals with EGb 761 (100 mg/kg, i.p. for 15 days) ahead of and during the induction of HD by 3-NP (20 mg/kg for 5 days starting at day 8) ameliorated 3-NP-induced neurobehavioral deficits. Administration of 3-NP increased the level of striatal malondialdehyde (MDA). This effect was prevented in animals pre-treated with EGb 761. Changes in the level of apoptotic regulatory gene expressions, following 3-NP treatment, were demonstrated as both an up-regulation and a down-regulation of the expression levels of striatal Bax and Bcl-xl genes, respectively. In addition, an up-regulation of the expression level of striatal glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was also observed. Pre-treatment with EGb 761 caused a down-regulation in striatal GAPDH and Bax together with an up-regulation of striatal Bcl-xl expression level as compared to the 3-NP treated group. Histochemical examination of striatal tissue showed that EGb 761 significantly prevented 3-NP induced inhibition of SDH activity. Histopathological examination further affirmed the neuroprotective effect of EGb 761 against 3-NP toxicity.Taken together, these results suggest that EGb 761 has a neuroprotective role in the current HD paradigm, which may be related to improvement of energy metabolism, antioxidant properties and antiapoptotic effects. 相似文献
68.
银杏外种皮提取液对菜粉蝶幼虫的毒力研究 总被引:3,自引:0,他引:3
用银杏外种皮水煮提取液进行室内菜粉蝶毒力实验和田间药效测定试验。结果表明,相当于0.75g/ml的银杏外种皮提取液对菜粉蝶3龄幼虫室内浸虫试验,幼虫死亡率为76.6%,浸叶饲喂健虫的幼虫死亡率为63.3%。0.15g/ml银杏外种皮提取液对菜粉蝶3龄幼虫室内浸虫试验,幼虫死亡率为53.3%,浸叶饲喂健虫死亡率为43.3%。0.75g/ml的银杏外种皮提取液对菜粉蝶5龄幼虫室内浸虫试验,幼虫死亡率仅为33.3%。0.75g/ml银杏外种皮提取液对菜粉蝶3龄幼虫田间药效测定,其幼虫死亡率为64%,校正防治效果为63.6%。 相似文献
69.
70.