不同溶剂法对西南委陵菜根、叶的总黄酮含量测定

分别采用95%乙醇、70%乙醇和甲醇溶液三种溶剂为提取液,用分光光度法测定西南委陵菜(Potentillafuigens)根、叶总黄酮含量,比较其提取物的提取率,结果表明70%乙醇溶液是较好的提取液。西南委陵菜根、叶总黄酮含量分别为24.15%、9.62%。     

Neuroprotective effects of flavonoids extracted from licorice on kainate-induced seizure in mice through their antioxidant properties

A relationship between status epilepticus (SE) and oxidative stress has recently begun to be recognized. To explore whether the flavonoids extracted from licorice (LFs) have any protective effect on kainate (KA)-induced seizure in mice, we treated mice with LFs before and after KA injection. In KA-treated mice, we found that superoxide dismutase (SOD) activity decreased immediately after the onset of seizure at 1 h and then increased at 6 h. It returned to baseline 1 d after seizure and then increased again at 3, 7, and 28 d, while malondialdehyde (MDA) content remained at a high level at 1 h, 6 h, 3 d, 7 d, and 28 d, indicating a more oxidized status related to the presence of more reactive oxygen species (ROS). Treatment with LFs before KA injection reversed the seizure-induced change in SOD activity and MDA content at 1 h, 6 h, 3 d, 7 d, and 28 d. Treatment with LFs after seizure decreased KA-induced SOD activity and MDA content at 7 and 28 d. Also, LF pre- and post-KA treatments decreased seizure-induced neuronal cell death. Subsequently, Morris water maze tests revealed that the escape latency was significantly decreased and the number of target quadrant crossings was markedly increased in the LF-treated groups. Thus, our data indicate that LFs have protective effects on seizure-induced neuronal cell death and cognitive impairment through their anti-oxidative effects.     

Promoting role of an endophyte on the growth and contents of kinsenosides and flavonoids of Anoectochilus formosanus Hayata, a rare and threatened medicinal Orchidaceae plant

Anoectochilus formosanus, commonly known as “Jewel Orchid”, is a Chinese folk medicine used to treat hypertension, diabetes, and heart disease. The existence of A. formosanus is currently threatened by habitat loss, human and animal consumption, etc. The highly potent medicinal activity of A. formosanus is due to its secondary metabolites, especially kinsenosides and flavonoids. This orchid also has a unique mycorrhizal relationship. Most adult orchids rely on endophytes for mineral nutrition and have complex interactions with them, which are related to plant growth, yield and changes in secondary metabolites. This study investigated the promoting role of F-23 fungus (genus Mycena) on the biomass and contents of kinsenosides and flavonoids of A. formosanus in pot culture. The following were observed after 10 weeks of symbiotic cultivation: increased shoot height, shoot dry weight, and leaf numbers by 16.6%, 31.3%, and 22.5%, respectively; increased contents of kinsenosides, isorhamnetin-3-O-β-d-rutinoside, and isorhamnetin-3-O-β-d-glucopyranoside by 85.5%, 226.1%, and 196.0%, respectively; some hyphae in epidermal cells dyed red and/or reddish brown by safranine; and, significantly reduced number of starch grains in cortical cells. Moreover, F-23 fungus significantly improved the kinsenoside and flavonoid contents of A. formosanus. These findings supported the reports that endophytes can alter the production of secondary metabolites in their plant hosts, although further physiological, genetic and ecological analyses are warranted.     

金银花和叶中黄酮类化合物提取工艺条件的探讨

采用L9(34)正交实验探讨了从金银花及金银花叶中提取黄酮类化合物的影响因素,获得最佳提取工艺参数.     

正交设计提取酸模中黄酮化合物

采用正交设计法对酸模（Rumexacetosa Linn．）中黄酮类化合物的最佳提取工艺进行了初步研究。结果显示最佳提取工艺组合为,即乙醇浓度85％、提取时间3h、料液比1：10。影响提取的因素依次为：提取时间〉乙醇浓度〉溶媒倍数。     

南疆地区核桃叶中总黄酮的测定

采用分光光度法对喀什地区核桃叶中黄酮类化合物的总含量进行了测定.用70%乙醇多次超声提取黄酮类化合物,以芦丁为对照品,NaNO2-Al（NO3）3-NaOH为显色系统,在510 nm处进行分光光度测定,建立标准曲线回归方程A=12.432C+0.019,线性相关系数R2=0.9974,测定结果表明,核桃叶中黄酮类化合物的总含量为0.0346 mg/g.     

银杏叶黄酮种类、含量变化及形成规律与调控

经作者研究归纳,报道了银杏叶黄酮的种类、银杏叶黄酮含量的变化及其影响因子、银杏叶子黄酮生物体内的合成途径及其生理生化机制、银杏叶黄酮的体外合成等,并对今后银杏叶黄酮的调控研究提出了4点建议。     

山楂黄酮提取工艺研究

对山楂总黄酮含量的提取,不同工艺影响很大。本文采用单因素和正交实验法方法研究不同工艺条件对山楂黄酮提取效率的影响,得出最佳浸提工艺及相关工艺参数。     

土荆芥总黄酮含量的测定

以芦丁为标准品,采用70%乙醇溶液、甲醇溶液和乙酸乙酯溶液三种不同溶剂分别连续回流提取土荆芥全草,用分光光度法于510mm处测定土荆芥中总黄酮含量,结果表明:70%乙醇溶液是相对较好的提取溶剂;再以70%乙醇溶液为溶剂连续回流提取土荆芥不同部位,测得其根、茎和种子中总黄酮含量分别为0.075%、0.045%和0.318%。     

海金沙总黄酮提取物对花生油抗氧化稳定性影响

在花生油中添加海金沙总黄酮提取液,考查了温度、过氧水和紫外光对花生油过氧化值的影响．结果表明：常温反应10h,花生油中添加4mL海金沙总黄酮提取液的过氧化值比不加小50．26％;分别于90℃加热和0．03％过氧水氧化10h,花生油中添加海金沙总黄酮提取液的过氧化值比不加小21．13％和17．4％;用紫外灯照射10h,添加海金沙总黄酮提取液的花生油,其过氧化值比不加小11．85％．羟基自由基清除能力实验表明：花生油中添加10mL海金沙总黄酮提取物的自由基清除率是不加的2．57倍．