高效液相色谱法测定小儿感冒颗粒中靛蓝与靛玉红含量

目的建立小儿感冒颗粒中靛蓝与靛玉红含量测定方法。方法采用依利特Hypersil BDS C18色谱柱(4.6 mm×200 mm,5μm);流动相:甲醇-水(74∶26);流速:1.0 ml/min;检测波长:289nm;柱温:30℃。结果靛蓝的线性范围为0.00117～0.0234μg(r=0.999 7),平均回收率为98.24%,RSD=1.16%(n=6);靛玉红的线性范围为0.00141～0.0281μg(r=0.999 7),平均回收率为98.90%,RSD=1.17%(n=6)。结论该方法准确可靠、简单快速,可用于小儿感冒颗粒质量控制。     

Antioxidant activity and total phenolic content of ethanolic extract of Caesalpinia bonducella seeds

The aim of this study was to assess the in vitro potential of ethanolic extract of Caesalpinia bonducella seeds as a natural antioxidant. The DPPH activity of the extract (20, 40, 50, 100 and 200 μg/ml) was increased in a dose dependent manner, which was found in the range of 38.93–74.77% as compared to ascorbic acid (64.26–82.58%). The IC₅₀ values of ethanolic extract and ascorbic acid in DPPH radical scavenging assay were obtained to be 74.73 and 26.68 μg/ml, respectively. The ethanolic extract was also found to scavenge the superoxide generated by EDTA/NBT system. Measurement of total phenolic content of the ethanolic extract of C. bonducella was achieved using Folin–Ciocalteau reagent containing 62.50 mg/g of phenolic content, which was found significantly higher when compared to reference standard gallic acid. The ethanolic extract also inhibited the hydroxyl radical, nitric oxide, superoxide anions with IC₅₀ values of 109.85, 102.65 and 89.84 μg/ml, respectively. However, the IC₅₀ values for the standard ascorbic acid were noted to be 70.79, 65.98 and 36.68 μg/ml respectively. The results obtained in this study clearly indicate that C. bonducella has a significant potential to use as a natural antioxidant agent.     

Chemoprevention of rat mammary carcinogenesis by Azadirachta indica leaf fractions: Modulation of hormone status,xenobiotic-metabolizing enzymes,oxidative stress,cell proliferation and apoptosis

We evaluated the chemopreventive potential of the ethyl acetate fraction (EAF) and methanolic fraction (MF) of Azadirachta indica (neem) leaf on 7,12-dimethylbenz[a]anthracene (DMBA)-induced rat mammary carcinogenesis. Estradiol and estrogen receptor status, xenobiotic-metabolizing enzyme activities, redox status, DNA and protein modifications, and the expression of cell proliferation, and apoptosis related proteins in the mammary gland and liver were used as biomarkers of chemoprevention. Administration of both EAF and MF at a dose of 10 mg/kg bw effectively suppressed tumour incidence. Chemoprevention by neem leaf fractions was associated with modulation of hormone and receptor status, xenobiotic-metabolising enzymes, and lipid and protein oxidation, with upregulation of antioxidants, inhibition of oxidative DNA damage, protein modification, and cell proliferation, and induction of apoptosis. However EAF rich in constituent phytochemicals was more effective than MF in modulating multiple molecular targets. These results provide evidence for the chemopreventive efficacy of neem leaf fractions in the rat mammary tumour model.     

In vitro antioxidant activity and total phenolic content of ethanolic leaf extract of Stevia rebaudiana Bert.

The aim of this study was to assess the in vitro potential of ethanolic leaf extract of Stevia rebaudiana as a natural antioxidant. The DPPH activity of the extract (20, 40, 50, 100 and 200 μg/ml) was increased in a dose dependent manner, which was found in the range of 36.93–68.76% as compared to ascorbic acid 64.26–82.58%. The IC₅₀ values of ethanolic extract and ascorbic acid in DPPH radical scavenging assay were obtained to be 93.46 and 26.75 μg/ml, respectively. The ethanolic extract was also found to scavenge the superoxide generated by EDTA/NBT system. Measurement of total phenolic content of the ethanolic extract of S. rebaudiana was achieved using Folin–Ciocalteau reagent containing 61.50 mg/g of phenolic content, which was found significantly higher when compared to reference standard gallic acid. The ethanolic extract also inhibited the hydroxyl radical, nitric oxide, superoxide anions with IC₅₀ values of 93.46, 132.05 and 81.08 μg/ml, respectively. However, the IC₅₀ values for the standard ascorbic acid were noted to be 26.75, 66.01 and 71.41 μg/ml respectively. The results obtained in this study clearly indicate that S. rebaudiana has a significant potential to use as a natural antioxidant agent.     

A 13-week subchronic toxicity study of dietary administered saponin-rich and isoflavones-containing soybean extract in F344 rats

A subchronic toxicity study of soybean extract was performed in F344 rats with dietary administration at concentrations of 0%, 1.25%, 2.5% and 5% for 13 weeks. No mortality or abnormal clinical signs in any group were observed. Body weight gains were decreased with a tendency for reduction of feed intake in the 1.25% and above female and 5% male groups. In males, absolute and relative liver weights were increased in the 1.25% and above groups. In females relative kidney weights were increased in the 1.25% and above groups. Other significant changes such as decreased RBC and hematocrit and increased urea nitrogen were detected in the 2.5% and/or 5% groups. On histopathological observation, atrophy of the ventral prostate was observed in all animals in the 5% male group. Mucification and atrophy of the vaginal epithelium and increased atretic follicles in ovaries were noted in 2.5% and 5% female rats. Based on the above findings the lowest-observed-adverse-effect level for male and female rats was estimated to be 1.25% (707.2 and 751.8 mg/kg b.w./day, respectively).     

地稔水提液抗氧化活性的紫外光谱快速预测方法

目的 建立基于紫外光谱和偏最小二乘回归算法的地稔水提液抗氧化活性快速预测方法.方法 采用1,1-二苯基-2-苦腈基(DPPH)自由基清除活性表征地稔水提液的抗氧化活性,采集190～600 nm的紫外光谱,通过优化光谱波长范围和预处理方法,建立抗氧化活性与紫外光谱的最优偏最小二乘回归模型.采用Visual Basic开发...     

银杏叶提取物对高糖环境下ECV304细胞的保护作用

目的：探讨银杏叶提取物对高糖环境下人脐静脉内皮细胞（ECV304）的保护作用及机制。方法：体外培养的ECV304细胞分为高糖组、银杏叶保护组、甘露醇高渗对照组（甘露醇组）和正常细胞组,在35 mmol•L^-1高糖条件下培养ECV304细胞24 h后,分别收集不同处理组的细胞,检测细胞产生羟自由基（•OH）、超氧阴离子（O^-₂）、丙二醛(MDA)水平,同时测定细胞超氧化物歧化酶（SOD）活性;采用不同处理组的细胞制作扫描电镜图片,观察细胞及线粒体形态的改变。结果：高糖组细胞产生•OH、O^-₂和MDA水平高于银杏叶保护组（P<0.05）,SOD活性低于银杏叶保护组（P<0.05）。甘露醇组细胞产生•OH、O^-₂、MDA水平显著低于高糖组（P<0.05）。电镜下可见银杏叶保护组线粒体形态完好,线粒体内嵴清晰可见;高糖组线粒体肿胀,线粒体内嵴消失,坏死细胞增多。结论：银杏叶提取物对高糖导致的ECV304细胞损伤具有保护作用。     

滇桂艾纳香不同提取物急性毒性研究

目的：观察滇桂艾纳香药材用不同溶剂提取的浸膏灌胃给予小鼠后产生的急性毒性反应和死亡情况。方法：预实验发现50%、70%乙醇提取物毒性不明显,无法测定半数致死量（LD50）,需改作最大耐受量（MTD）试验,并且初步确定水提取物半数致死量（LD50）试验用药剂量,正式实验采用小鼠灌胃给药的方法测定水提取物半数致死量（LD50）和50%、70%乙醇提取物最大耐受量（MTD）。结果：滇桂艾纳香水提取物的LD50为143.1034g生药/kg,50%、70%乙醇提取物MTD分别259.60g生药/kg、309.68g生药/kg。结论：滇桂艾纳香毒性较小,临床用药安全,且水提取物毒性大于醇提取物。     

白花蛇舌草提取物体外对人胃癌细胞SGC-7901增殖抑制作用的实验研究

目的探讨白花蛇舌草提取物体外对人胃癌细胞SGC-7901增殖的抑制作用。方法通过体外无菌传代培养人胃癌细胞SGC-7901,将白花蛇舌草提取物以0．05mg/mL、0．1mg／mL、0．15mg／mL、0．2mg／mL四个不同浓度作用于该细胞,24h后采用MTF法检测细胞活性及数量。结果药物组0．05mg／mL和0．1mg／mL浓度孔的吸光值与对照组相比无显著性差异（P〉0．05）,而0．15mg／mL和0．2mg／mL浓度孔的吸光值明显小于对照组（P〈0．05）。结论白花蛇舌草提取物体外对人胃癌细胞SGC-7901增殖有一定的抑制作用,且抑制作用的强弱可能跟药物浓度有关,值得进一步研究。