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XIE Xueqiang 《Journal of Landscape Research》2020,(2):95-98
The native and introduced ground cover plants were screened by field survey,cultivation test and configuration effect evaluation in arid valleys of Ganzi Tibetan area.A total of 205 species belonging to 140 genera,67 families were selected as applicable types.Among them,there were 53 species of evergreen shrubs,36 species of deciduous shrubs,17 species of woody vines,99 species of herbaceous plants;27 species of color-leafed plants,8 species of succulent plants.And 79 species were recommended as the best ground cover plants.Higher plants in Ganzi Tibetan area were increased to 5,362 species,1147 genera,244 families through screening. 相似文献
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我国是畜牧业和畜禽产品生产、消费大国,肉类的产量居世界第一位.但畜产品的出口量却不多,这很大程度上源于我国的畜产品存在质量安全问题.随着人们安全意识的不断提高,以及我国加入WTO,发展无污染、无残留、对人类健康无损害的畜产品已成为必然选择.…… 相似文献
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以山杏幼叶为材料,比较了4种DNA提取方法。结果表明,处理为100mmol/LTris2HCl（pH8.0）、20mmol/LEDTA（pH8.0）、1.4mmol/LNaCl、2%CTA、10mmol/LNa2S2O5、2%β-巯基乙醇、1%PVP-40、1%Vc的CTAB4方法提取的基因组总DNA质量较高,DNA溶液无色透明,紫外分光光度计测得OD260/OD280为1.8～2.0,无降解现象,RNA去除干净,经AFLP分析条带清晰,多态性好,说明此法提取的DNA能够适应AFLP分析的要求。 相似文献
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功能性复方荷叶袋泡茶的研制 总被引：2，自引：0，他引：2
采用荷叶、菊花和茶叶三种原料,通过两两组合选优、再三者组合优化配比,试图筛选出口感好、营养成分搭配合理的最佳配方。结果表明：组合chj2营养保健成分氨基酸和茶多酚含量较高,含水量较低,感官评定茶汤绿色清澈、香气清新、口感纯正,是一种较理想的配比组合。包装袋大小、冲茶水温、制作原料等因素对袋泡茶茶水品质有较大影响,要求包装袋大小适中,以容纳3～4g的规格大小为宜;水温一般以80～90℃比较好,冲泡后茶汤香气清新、汤色清绿、味道纯正;原料要求新鲜无霉变、品质纯正,确保袋泡茶质量。 相似文献
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The advances in the treatment of heart failure with Yangxinshi tablet are reviewed in this paper.Yangxinshi tablet has effects of nourishing myocardia,improving myocardial metabolism,reducing myocardial oxygen consumption,dilating coronary artery,improving cardiac blood supply,reducing blood viscosity and improving microcirculation,and it can improve the functions of heart and curative effect of heart failure. 相似文献
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夏枯草生殖生长期总黄酮积累规律及抗氧化活性研究 总被引：5，自引：0，他引：5
通过测定夏枯草生殖生长期各阶段不同器官的总黄酮含量,揭示夏枯草各器官总黄酮的积累规律。采用70%乙醇超声波提取,后用等体积的乙酸乙酯、正丁醇和水萃取,得到乙酸乙酯、正丁醇和水提取物,以BHT为对照,研究不同溶剂提取物的抗氧化活性。结果表明:夏枯草根、茎、叶中的黄酮含量随着生长进程而升高,至终花期达到最高;花穗中的黄酮含量在花盛期最高;各器官相比,叶中黄酮含量最高。夏枯草不同溶剂提取物及对照BHT清除DPPH.的能力高低次序为:乙酸乙酯提取物>正丁醇提取物>BHT>水提物,清除.OH的能力高低次序为:BHT>乙酸乙酯提取物>正丁醇提取物>水提物,并且不同溶剂提取物的抗氧化活性与其总黄酮含量呈较显著的相关性。夏枯草总黄酮具有良好的抗氧化活性,可在夏枯草花终期或果穗干枯期采集叶或全草提炼加工。 相似文献
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《Medicinal Plant》2015,(Z2)
[Objective] To research the effects of hydrochloric acid hydrolysis extraction on the antioxidant and antimicrobial activities of tannin extracts from Castanea mollissima,Cyclobalanopsis glauca and Quercus aliena. [Methods] Extracts from C. mollissima,C. glauca and Q. aliena were prepared by water extraction( WE) and ethanol extraction( EE) and HCl( 4 M) hydrolysis extraction( HE),respectively.Their DPPH radical scavenging capabilities,antimicrobial activities and gallic acid contents( GAC) were detected as well as the soluble tannin contents in dry leaves.[Results]The soluble tannin contents in C. mollissima,C. glauca and Q. aliena leaves were 87. 32,76. 89 and 51. 28 mg / g,respectively. HE increased the GAC in the extracts of C. mollissima and C. glauca by 15- 60 and 5- 15 times,respectively,while the GAC in the extracts of Q. aliena remained almost unchanged when compared with WE and EE. Meanwhile,the DPPH scavenging capabilities and antimicrobial activities were also enhanced by HE. C. albicans and C. tropicalis were more sensitive than others to the three plant extracts,especially to C. glauca. Unexpectedly,C. glauca had the highest antimicrobial activity,but its tannin and gallic acid contents were only moderate,indicating that other substance with higher antimicrobial activity existed. [Conclusions]HE enhanced the antioxidant and antimicrobial activities of tannin rich extracts of the three plant leaves from the Fagacae family. 相似文献
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为探究红枣枣果在成熟过程中相关品质及抗氧化活性的变化规律,以不同成熟度(未成熟青白果、四成熟微红果、八成熟半红果和成熟全红果)的狗头枣枣果为研究材料,探究其不同成熟阶段酚类物质、有机酸、三萜酸、VC含量及抗氧化活性(DPPH自由基清除能力,总还原力)的差异性。结果表明:4个不同成熟度红枣共检测出8种酚类物质、4种有机酸、3种三萜酸,其中儿茶素、阿魏酸、绿原酸为主要的酚类物质,柠檬酸和苹果酸为主要的有机酸,白桦脂酸和熊果酸为主要的三萜酸。4个成熟度红枣总酚含量为556.7~963.7 mg/100 g,总黄酮含量为412.7~866.7 mg/100 g,VC含量为335.5~665.5 mg/100 g,这3种物质含量皆在青白果时期最高,且随着成熟度的提高呈下降趋势;枣果的抗氧化能力由高到低为未成熟青白果>四成熟微红果>八成熟半红果>成熟全红果。枣果在未成熟青白果时的VC、总酚、总黄酮含量最高,抗氧化活性最强,可作为获取天然抗氧化活性物质的原材料。 相似文献
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小米加工成米粥后供人食用,为研究其在加工过程中生理活性物质的变化规律,对小米经高压蒸煮、冷冻干燥、复水加工制成速食小米粥过程中氨基酸、酚酸、黄酮含量及提取物的抗氧化能力变化进行研究。结果表明,总氨基酸与必需氨基酸含量在加工过程中无显著性差异,小米中结合态酚酸高压蒸煮后降低27.87%,对小米中自由态黄酮经高压蒸煮后降低29.57%。冷冻干燥和复水对酚酸与黄酮含量影响不显著。复水后小米粥中的香草酸含量与小米相比增长73.94%。复水小米粥中自由态与结合态酚酸提取物清除DPPH自由基能力分别比小米中降低55.83%和88.39%;高压蒸煮后自由态与结合态酚酸提取物三价铁还原能力显著下降,分别下降30.08%和39.74%;冷冻干燥和复水对酚酸提取物三价铁还原能力无显著影响。 相似文献
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枇杷叶总黄酮超高压提取及抗氧化活性 总被引：2，自引：0，他引：2
为研究超高压提取的枇杷叶总黄酮的抗氧化能力。选用L9(34) 正交实验对枇杷叶总黄酮的提取工艺条件进行优选,以总黄酮得率为指标,考察乙醇浓度、超高压压力、超高压提取时间、固液比(g：mL)对总黄酮得率的影响。并且测定了总黄酮对DPPH自由基的清除作用。结果表明：总黄酮提取最佳工艺条件为：乙醇浓度50%、超高压压力400Mpa、超高压提取时间4.5min、固液比1：18。该条件下总黄酮的得率可达0.693%,总黄酮浓度和对DPPH自由基的清除作用呈现线性相关。超高压提取的总黄酮具有较强的抗氧化能力,具有较高的应用价值。 相似文献
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Abdelnaser Abdelghany Elzaawely Shinkichi Tawata 《Journal of Crop Science and Biotechnology》2012,15(1):59-64
Rumex dentatus L. (Family: Polygonaceae) is a weedy plant widely distributed in many countries including Egypt. It has been used in the
Mediterranean diet as a leafy vegetable and its leaves and roots exhibited various biological activities. In our study, total
phenolics, antioxidant capacities assayed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and β-carotene bleaching methods and reducing power were evaluated in different extracts/fractions of leaves and roots of R. dentatus grown in Egypt. In addition, their phenolic compositions were determined by GC-MS and HPLC. The results showed that total
phenolic content in the ethyl acetate fractions of leaves and roots were high and measured at 169.5 and 257.4 mg gallic acid
equivalent per g extract, respectively. The ethyl acetate fractions of leaves and roots exhibited strong DPPH activity and
the DPPH IC50 values were 0.021 and 0.012 mg mL−1 of leaves and roots, respectively. Furthermore, the ethyl acetate fractions of leaves and roots showed high reducing power
and antioxidant activity assayed by β-carotene bleaching method. GC-MS and HPLC analyses indicated that these fractions contained a variety of phenolic compounds
including p-hydroxybenzoic acid, syringic acid, vanillin, benzoic acid, ferulic acid, and cinnamic acid. Our study verified that the
ethyl acetate fractions of leaves and roots of R. dentatus have strong antioxidant activities which are correlated with its high levels of phenolic compounds and therefore, they could
be utilized as a natural source of antioxidant in food industry. 相似文献
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不同干燥处理对马齿苋总酚含量及其抗氧化性的影响 总被引：2，自引：0，他引：2
分别采用热风干燥法、真空微波干燥法和真空冷冻干燥法处理马齿苋,测定马齿苋粉甲醇提取液的总酚含量、总抗氧化能力、还原能力、DPPH·清除能力、羟自由基清除能力和超氧阴离子自由基清除能力,研究不同干燥方法对马齿苋粉总酚含量和抗氧化性的影响。结果表明,真空冷冻干燥法制得的马齿苋干粉样品中总酚含量显著高于真空微波与热风干燥样品;不同的干燥方法对马齿苋粉的抗氧化性有明显影响,真空冷冻干燥法制得的马齿苋粉甲醇提取液的总抗氧化能力、还原能力、DPPH·与羟自由基清除能力显著高于真空微波和热风干燥法制得的马齿苋粉(P0.05),但真空冷冻干燥样品与真空微波干燥样品对O_2~-·的清除率无显著差异,综合考虑产品品质与加工成本,采用真空微波干燥法更为合理。 相似文献
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以春季茶树碧香早的一芽二叶茶鲜叶为原料,将其固定及分别加工成六大茶类,比较研究了相同加工茶鲜叶及其干茶质量下的六大茶类体外抗氧化性能,以期为茶叶新产品开发及健康消费提供科学依据。结果表明,固定样及六大茶类的还原能力和清除DPPH.、亚硝基、.OH及O2-.的能力均随茶汤浓度的增加而增强;固定样、绿茶、黄茶、黑茶、乌龙茶、白茶以及红茶对DPPH.的IC50依次为0.017、0.019、0.019、0.020、0.021、0.022和0.038mg干茶浸出物/ml,绿茶、固定样、乌龙茶、黑茶、白茶、黄茶和红茶对.OH的IC50依次为1.438、1.695、2.988、4.163、4.606、4.881和6.847mg干茶浸出物/ml,固定样、乌龙茶、黄茶、绿茶、白茶、黑茶和红茶对亚硝基的IC50依次为1.285、1.401、1.514、1.525、1.847、2.146和5.163mg干茶浸出物/ml。说明由相同原料加工而成的六大茶类在浸泡相同质量干茶的条件下,因其加工工艺的不同而在体外抗氧化性能上存在差异,固定样及六大茶类的抗氧化能力大小在总体上呈现不发酵茶(绿茶)＞半发酵茶(乌龙茶)＞全发酵茶(红茶)的趋势,其中以清除DPPH.的效果最好。 相似文献
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测定了三种绿茶的总多酚、黄酮和花青素含量,利用亚铁离子螯合能力、DPPH清除能力和铁还原力法对三种绿茶提取物的抗氧化活性进行分析,结果表明绿茶中以黄山毛峰的总酚含量最高。黄酮含量基没有显著性差异。花青素的含量由大到小依次是信阳毛尖、黄山毛峰和营州芽峰。亚铁离子螯合能力,黄山毛峰>信阳毛尖>营州芽峰。在稀释倍数为2时,黄山毛峰的亚铁离子螯合能力分别是信阳毛尖和营州芽峰的1.32倍和1.38倍。在0.25-1mgDW/mL的浓度下,黄山毛峰的对DPPH的清除能力要显著高于信阳毛尖和营州芽峰,而信阳毛尖和营州芽峰之间无显著性差异。在稀释倍数为2时,黄山毛峰的铁还原力分别是信阳毛尖和营州芽峰的1.35和1.4倍。 相似文献