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以金荞麦叶和覆盆子叶为植物原料,经酵母菌发酵制备农用酵素营养液,研究其发酵过程中主要营养组分的动态变化规律。结果表明,随着发酵时间的延长,金荞麦叶和覆盆子叶农用酵素营养液各营养组分的变化趋势类似。游离氨基酸含量呈先上升后下降趋势;总氮含量呈不规则变化;总酚、总酸和总磷含量总体呈上升趋势;总糖含量呈下降趋势;钾离子含量呈先升高后下降再上升变化。但两者养分含量除钾离子外差异较为明显。金荞麦叶农用酵素营养液的总氮、游离氨基酸以及总酸含量高于覆盆子叶农用酵素营养液;而覆盆子叶农用酵素营养液的总糖、总磷和总酚含量较高。 相似文献
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目的:利用课堂教材上的经典提取方法-pH梯度萃取法,提取中药大黄中的游离蒽醌组分(大黄酸、大黄素、芦荟大黄素、大黄酚、大黄素甲醚),并计算其含量,考察课堂教学实验中提取大黄游离蒽醌中各组分总含量是否符合中国药典规定。方法:利用pH梯度萃取法提取并计算各组分含量。结果:大黄酸0.018%、大黄素0.48%、芦荟大黄素0.38%、大黄酚0.76%、大黄素甲醚0.38%,结论:大黄游离蒽醌组分的总含量为2.02%,符合中国药典不低于1.5%的规定。 相似文献
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《内江科技》2018,(10)
目的:通过Box-Behnken响应面法优化女贞叶中熊果酸的提取工艺。方法:采用加热回流提取女贞叶中熊果酸,通过单因素考察了提取溶剂浓度、液料比、提取时间对女贞叶中熊果酸提取率的影响,并通过Box-Behnken响应面法优化提取工艺,得到熊果酸最优提取工艺条件。结果:经实验优化确认女贞叶中的熊果酸最优提取工艺为:提取液使用95%乙醇,液料重量比为14.5,持续提取1.5 h,并经过重复3次提取实验验证表明,女贞叶中熊果酸的提取率的实测值与预测值误差较小,说明实验预测较为准确。结论:运用Box-Behnken响应面法优化女贞叶中熊果酸的提取工艺,实验次数少,预测准确度高,同时为其他中药材的提取提供借鉴意义。 相似文献
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目的:提取马尾松松针挥发油,测定其水溶液总酚含量和分析研究挥发油化学成分。方法:采用水蒸气蒸馏法提取挥发油,采用Folin-Ciocalteau法测定水溶液中总多酚含量,并通过GC/MS技术对挥发油进行分析。结果:GC/MS技术鉴定出10个成分(见表1)。结论:总多酚含量为6.56mg/ml;挥发油主要由烷烃(72.88%,相对质量分数,下同)、醇(12.93%)、醚(14.19%)组成,其中烷烃含量最多。 相似文献
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文章优化了八角茴香莽草酸的提取方法。分别考察了单因素料液比、超声波功率、提取温度、提取时间的影响,并在单因素基础上进行了4因素3水平正交设计试验,得到最佳提取工艺为:料液比:1∶28(g:mL),超声波功率190W,提取时间20 min,提取温度53℃。在最优工艺下分别测定了桂西地区不同地方八角茴香莽草酸含量,结果表明大新的样品含量最高,达到8.21%,隆林的样品含量最低为5.87%。 相似文献
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本文研究了以香樟叶为原料,利用有机溶剂浸取及微波辅助方法研究香樟精油提取工艺。探讨了溶剂种类、微波功率、微波时间、料液比对香樟叶中精油提取效果的影响,并通过正交试验确定其最佳提取工艺。结果表明:无水乙醇为最佳提取溶剂,最佳提取条件为:微波功率700W,微波时间10min,料液比8:1。在此条件下,香樟叶的出油率达4.26%。 相似文献
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采用碘量法和2,6-二氯靛酚滴定法两种方法对样品鲜枣中维生素C含量的测定,比较两种方法结果表明,2,6-二氯靛酚滴定法的精密度更好,而碘量法操作快捷,适应于即时测定。 相似文献
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研究不同贮存条件下,肉桂叶精油中微量萜类化合物的种类和相对百分含量变化。采用水蒸气蒸馏法对鲜肉桂叶及分别在不同贮存温度(15℃、20℃、25℃、30℃、室温)下贮存不同时间(0～90d)肉桂叶中的挥发性成分进行提取,得到的肉桂叶精油采用气相色谱-质谱联用技术进行分析测定,以面积归一法计算其中微量(相对含量0.1%～1.0%)萜类化合物的相对百分含量。在贮存过程中共检测到13种微量萜类成分,分别为(-)-龙脑、γ-依兰油烯、β-杜松烯、香树烯、(-)-α-蒎烯、α-人参烯、石竹烯、喇叭烯、桉油烯醇、库贝醇、毕橙茄醇、α-红没药醇、绿花白千层醇。不同贮存条件下肉桂叶精油微量萜类成分的种类和含量均有较大差异,贮存80d以上的肉桂叶中基本不含萜类成分。该研究为肉桂采摘后植物体内的生物合成途径及机理等方面的研究提供依据,为肉桂油的产业化生产提供参考。 相似文献
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分光光度法测定蒙古栎叶中多酚的含量 总被引：2，自引：0，他引：2
以没食子酸为标准品,使用福林酚试剂(FC),通过分光光度法,对蒙古栎树叶中植物多酚含量进行了测定.首先从方法的稳定性、线性关系、精确性和准确性角度,对FC法进行了调整,确定了以没食子酸为标准的最佳反应条件.结果表明,最佳反应条件为0.15mL FC试剂(1mol/L),0.15mL 10%体积分数的Na2CO3,25℃反应80min后于760nm处测吸光值.使用调整后的方法测得结果为:蒙古栎叶中总酚含量为6.39%,RSD为1.90%.方法操作简单,结果重现性好, 可用来测定蒙古栎叶中总酚的含量. 相似文献
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Free radical generation and lipid peroxidation among the dry cell industry workers exposed to carbon
K. K. Reddy T. P. K. Reddy B. V. Somasekharaiah K. Soorya Kumari 《Indian journal of clinical biochemistry : IJCB》1998,13(1):27-32
A total of 75 healthy male dry cell industry workers exposed to carbon for 5, 8 and 10 years were compared with 48 controls
matched for age and economic status with respect to free radical generation, lipid peroxidation and antioxidant levels. Lymphocytes
were seperated from the whole blood and used for estimation of free radicals and antioxidants. Plasma lipid peroxidation products
were estimated in the form of thiobarbituric acid reactive substances. Significant increase in free radical generation and
lipid peroxidation products were observed in carbon exposed population than controls, and the increase was found to be significant
with increase in the period of exposure. The levels of antioxidants i.e., superoxide dismutase (SOD) and catalase were found
to decrease with the increase in exposure to carbon in industrial workers. These results suggest that exposure to carbon augments
free radical generation, lipid peroxidation and promotes decline in antioxidant enzymes. 相似文献
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1961-2013年东北三省极端气候事件时空格局及变化 总被引：1，自引：0，他引：1
东北三省是中国重要的商品粮基地。本文基于东北三省1961-2013年71个台站逐日气温、降水资料,选取了“欧洲地区极端事件统计和区域动力降尺度”（STARDEX）项目提出的57个极端指数中的8个核心指数,分析和揭示东北三省极端气候事件的空间格局及变化,研究结果可为降低东北三省自然灾害对农业生产的影响,以及制定应对气候风险的策略提供依据。研究结果表明：①年和四季的高温阈值、低温阈值与最长热浪天数均随时间呈现波动上升趋势,年和春、秋、冬季的霜冻日数随年际表现为下降趋势;②东北三省西南地区易发生极端高温事件,北部易发生极端低温事件。同时北部亦是年和春、秋霜冻日数的高值分布区,且高温热浪的天数相对较长（高温热浪的季节）;③年和秋季强降水阈值随时间呈现波动下降趋势,而春、夏和冬季强降水阈值呈现波动上升趋势;年和春、夏、冬季强降水比例和强降水日数亦随年际呈现波动上升趋势,秋季强降水比例和强降水日数则表现为下降趋势;年和春、秋、冬季的持续干期呈现下降趋势,夏季呈现上升趋势;④东南部是极端降水事件的高发区,夏季与春季、秋季为极端降水事件易发的季节,极端事件增多,且向西部蔓延。年与四季的持续干期的分布均呈现西长东短的特点。 相似文献
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Jyoti Sethi Sushma Sood Shashi Seth Anjana Talwar 《Indian journal of clinical biochemistry : IJCB》2004,19(2):152-155
Ocimum sanctum leaves have been traditionally used in treatment of diabetes mellitus. Dietary supplementation of fresh tulsi leaves in a
dose of 2 gm/kg BW for 30 days led to significant lowering of blood glucose levels in test group. Intake ofOcimum sanctum also led to significant increase in levels of superoxide dismutase, reduced glutathione and total thiols, but marked reduction
in peroxiodised lipid levels as compared to untreated control group. The leaves were found to possess both superoxide and
hydroxyl free radical scavenging action. The present observations establish the efficacy ofOcimum sanctum leaves in lowering blood glucose levels and antioxidant property appears to be predominantly responsible for hypoglycemic
effect. 相似文献
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Halim Eshrat M. Ali Hussain 《Indian journal of clinical biochemistry : IJCB》2002,17(2):115-123
This study was carried out to investigate the effect of oral feeding of water extract of fresh leaves ofAzadirachta indica (Fam:Meliaceae) in streptozotocin induced diabetes and its associated retinopathy in rats. Treatment of the diabetic rats with aqueous extract of leaves ofA. indica at a dose of 250 mg/kg body weight for 16 weeks resulted in gradual but significant fall in blood glucose and improvement in serum total, LDL and HDL cholesterol and triacylglycerol which increased in diabetic rats. It also showed improvement in body weight and reversed retinopathy. 相似文献
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Effect of oral administration of 2 ml per day of suspension (in water) of alcoholic extract of whole fruit of Trichosanthes dioica (2%) (=100 g fresh wt.=7 g dry wt.=1/15 g of alcoholic extract) with the help of catheter alongwith basal diet for four weeks have been studied in the normal albino rabbits. It was observed that this extract lowered the blood sugar, total cholesterol, low density lipoprotein cholesterol and triglyceride levels, and increased the high density lipoprotein cholesterol, phospholipid and faecal sterol levels. Such effects are manifested from the very first week of feeding and are statistically significant. 相似文献
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以佛指银杏为试材，通过1987-1988两年的试验，结果表明：种实的鲜重、干重、体积和纵横径的生长都是单S型生长曲线，纵横径生长高峰早于体积和鲜重，而鲜重的生长高峰又早于干重，种实及各组织间在一定时期内的生长均呈极显著正相关。 相似文献
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K Reshma V Rao Ashalatha M Dinesh DM Vasudevan 《Indian journal of clinical biochemistry : IJCB》2005,20(1):160-164
Flavonoids extracted from the leaves of Indian holy basil, Ocimum sanctum showed promising results as radioprotector in rodents.
Hence it was thought pertinent to analyze the antioxidants of erythrocytes in oral cancer patients who were concurrently treated
with radiation and ocimum flavonoids. Oral cancer patients consisted of 2 groups. Group A (n=17) received radiation alone
while Group B(n=17) received radiation and ocimum flavonoids(OF). Samples of heparinised blood were collected prior to treatment,
15 and 30 days respectively after treatment. Blood from normal healthy volunteers were taken as controls (n=25). Erythrocytes
were analyzed for the antioxidants viz. glutathione, glucose 6 phosphate dehydrogenase, glutathione peroxidase and superoxide
dismutase by the standard methods. Results of analysis indicated that erythrocytes from cancer patients (Group A and B) had
significantly high glutathione levels before as well as after treatment compared to controls. It was observed that Group B
which received OF showed a significant reduction in glutathione levels in comparison with Group A. All the other parameters
showed no statistical significant changes. Results of the study suggest that erythrocytes from cancer patients responded to
oxidative stress by elevating glutathione levels, while a decrease in glutathione levels observed in Group B, could be due
to the free radical scavenging effect of OF, sparing the glutathione. However OF did not seem to exert its effect on other
antioxidants of erythrocytes. 相似文献
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饮用水Ames致突变性与主要有机污染指标的关系 总被引：7，自引：1，他引：7
通过对某城市水源水、自来水及经不同组合工艺净化水Ames试验结果与主要有机污染指标的对应关系分析,发现诱发回变指数MA(TA98)主要与总有机碳有关。在此基础上进一步研究了几种常见有机微污染物与MA的关系。其研究成果对于认识饮用水致突变性,改进饮水深度处理工艺,提高饮水水质均具有指导作用。 相似文献
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黑龙江省1967年至2007年极端气温与降水综合强度的时空特征分析 总被引：3，自引：2，他引：1
利用黑龙江省73个气象站1967年-2007年的逐日气温和降水量资料, 基于极端气候事件综合强度模型方法, 分析了黑龙江省极端气温与降水事件的时空变化特征。研究表明:①极端高温事件综合强度在年代际变化上夏与秋季总体呈增强趋势, 20世纪90年代后增强更为显著。极端低温事件综合强度在年代际变化上春与冬季总体呈明显减弱趋势, 其中冬季减弱趋势较显著;②极端降水事件综合强度在年代际变化上春秋两季呈减弱趋势, 夏冬两季呈增强趋势, 其中秋季减弱较显著, 冬季增强较显著;③极端高温事件综合强度夏秋两季影响较重区域为松嫩平原西部和三江平原地区;极端低温事件综合强度春冬两季影响较重区域为三江平原地区、牡丹江地区北部和哈尔滨地区西北部;④极端降水事件综合强度春秋两季从西到东递增, 夏季中部地区较强, 冬季中部与东部地区较强;四季综合强度影响较重区域为大兴安岭最北端的漠河县、小兴安岭地区、三江平原东部边缘局部区域和牡丹江半山区。 相似文献