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1.
以一年生艾纳香种子苗为实验材料,用一水合氯化钙提供钙元素,在冬季艾纳香生长迟缓期进行3次施肥,测定艾纳香的株高、地径、叶长和叶宽等生长指标以及生物量。采用紫外可见分光光度法测定艾纳香不同部位中总黄酮的相对含量,并计算总黄酮的绝对含量;采用GC测定艾纳香叶片中l-龙脑的相对含量,并计算l-龙脑的绝对含量。结果表明:钙元素极显著增加了冬季生长迟缓期的艾纳香叶、茎和根生物量,其中5 g/L钙处理组的艾纳香叶生物量极显著高于其他3个处理组,10、15 g/L钙处理下的叶生物量极显著高于空白对照组(CK),分别是对照的3.03倍和2.65倍。钙元素的施加抑制了艾纳香不同部位总黄酮相对含量的积累,然而显著增加了总黄酮绝对含量。5 g/L钙处理组的l-龙脑相对含量和绝对含量最高,分别为0.22%和0.22 g,与10、15 g/L钙和CK组相比,分别增加了37.50%、22.22%、37.50%和100%、100%、450%。在冬季艾纳香生长迟缓期施加钙元素可以显著促进艾纳香叶、茎和根生物量的积累,提高总黄酮和l-龙脑的绝对含量。  相似文献   

2.
利用纤维素酶协同超声波提取技术对广金钱草中总黄酮的提取工艺进行筛选,通过单因素试验和L9(34)正交试验优选出纤维素酶协同超声波法提取总黄酮的最佳工艺为:乙醇浓度50%、料液比1:30,纤维素酶500mg,超声波提取时间30min.在该提取条件下黄酮得率为2.28%.本实验优选的工艺设计合理,稳定可行,抗氧化活性较好,...  相似文献   

3.
探讨艾纳香总黄酮对大鼠皮肤创伤愈合的影响及其作用机制。取大鼠150只,随机分为模型组、京万红组和艾纳香总黄酮高、中、低组,建立大鼠背部双侧圆形创伤模型,连续给药10 d,测定创面面积,计算愈合率;于术后的1、3 、5、7 、10 d检测创缘组织IL-1、TNF-α表达量并切取创伤边缘皮肤全层,制片,HE染色后镜下观察创面组织形态学的改变。结果表明:艾纳香总黄酮随药物剂量的增加而提高创面愈合百分率,缩短愈合时间,创伤早期增强创面IL-1、TNF-α的表达。艾纳香总黄酮促进大鼠皮肤创伤的愈合机制之一可能是增强创伤早期炎症因子的分泌,从而促进创面的修复愈合。  相似文献   

4.
通过对传统醇提法、超声波法、微波法、微波-超声协同法4种提取方法的比较,研究绿茶总黄酮的最佳提取方法。结果表明:微波提取法的最佳工艺条件为乙醇浓度70%,液固比45∶1,微波时间40s;微波-超声协同提取法最佳工艺为乙醇浓度70%,液固比45∶1,超声时间30min。4种提取方法以微波-超声协同提取法总黄酮得率最高,并比较4种提取方法获得的绿茶总黄酮提取物对羟自由基(·OH)的清除效果,超声提取法清除·OH效果最佳。  相似文献   

5.
为了优化千层塔全草中总黄酮的提取工艺。采用索氏提取方法,以总黄酮提取率为考察指标,通过单因素试验确定各因素对提取工艺的影响,正交试验确定最佳提取工艺。结果表明:影响千层塔总黄酮提取效率的主次因素依次为:乙醇浓度>温度>提取时间>料液比。千层塔中总黄酮最佳提取工艺为:乙醇浓度60%、提取时间130 min、提取温度85 ℃、料液比(g/mL)1 ∶ 35,千层塔中总黄酮提取率为1.262 6%。  相似文献   

6.
超声波辅助提取石崖茶总黄酮工艺优化   总被引:1,自引:0,他引:1  
应用正交试验方法对石崖茶总黄酮提取工艺进行优化。结果表明:各因素对总黄酮提取量影响大小依次为:料液比超声温度超声时间乙醇浓度。超声波辅助石崖茶总黄酮提取工艺最佳条件为料液比1∶40(g/m L)、乙醇浓度70%、超声时间30 min、超声温度55℃,此条件下总黄酮提取率为30.3%。采用该工艺测定广西昭平、桂平和金秀三个产地的石崖茶总黄酮含量,结果昭平石崖茶总黄酮含量最高,为30.4%。  相似文献   

7.
涂建飞  卢立  张晶 《人参研究》2013,25(2):43-45
目的测定菜豆豆荚总黄酮含量,优化菜豆中黄酮提取工艺。方法以芦丁为对照品通过紫外分光光度法测定总黄酮含量,将回流法、超声法、煎煮法提取黄酮类化合物的提取效率进行对比,采用正交法优化了超声提取工艺。用最佳提取工艺验证实验结果。结果提取次数对黄酮提取率影响显著.超声时间和乙醇浓度对提取率影响不显著。结论最佳提取工艺为85%乙醇、超声60min、提取3次,菜豆中总黄酮含量为158.86mg/100g。  相似文献   

8.
张野  杨世海 《人参研究》2012,24(2):28-30
目的优化酸枣仁中总黄酮的提取工艺。方法利用分光光度计通过测定吸光度测定酸枣仁中总黄酮的含量,采用正交试验,优选酸枣仁中总黄酮最佳提取工艺。结果最佳提取工艺为加10倍量,70%的乙醇,提取1次,每次1h。结论建立的酸枣仁总黄酮含量的测定方法,该方法简单、快捷,重现性好,可用于酸枣仁的质量控制和定量分析。优选的方法可靠,重现性好,可用于提取酸枣仁中总黄酮。  相似文献   

9.
目的确定葛根有效成份提取的最佳条件。方法以40%乙醇为溶剂,通过正交实验,以葛根总黄酮得率为评价指标,筛选最佳工艺条件。结果 40%乙醇为溶剂提取葛根总黄酮的最佳组合条件为提取时间120min,溶剂用量25倍,提取温度80℃,提取次数2次。结论该条件下葛根中总黄酮的得率为8.95%。此实验方法操作简单、快捷,具有高效性及安全性,适合工业化生产推广。  相似文献   

10.
通过单因素试验,分析乙醇浓度、提取温度、提取时间、料液比、提取次数等对总黄酮提取率的影响,采用正交试验确定山地五月茶总黄酮的最佳提取工艺。结果表明,山地五月茶总黄酮的最佳提取条件为乙醇浓度85%、料液质量体积比1∶10、提取温度90℃,加热回流提取2.0 h,提取3次。在此条件下,测得山地五月茶总黄酮的含量为(4.548 6±0.041 5)mg/g。本研究建立了山地五月茶总黄酮的提取工艺,可为山地五月茶资源的充分利用、研究开发等提供科学依据。  相似文献   

11.
12.
Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.  相似文献   

13.
Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.  相似文献   

14.
15.
Novel food and non-food uses for sorghum and millets   总被引:4,自引:3,他引:4  
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.  相似文献   

16.
Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.  相似文献   

17.
Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X1 (also called RXact).  相似文献   

18.
The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O2•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O2•− scavenging, (IC50 = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC25 = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC50 = 863 µg/mL; elastase, IC50 = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O2•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.  相似文献   

19.
The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.  相似文献   

20.
Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules contributes to many possible adsorption interactions between chitosan and pollutants (dyes, metals, ions, phenols, pharmaceuticals/drugs, pesticides, herbicides, etc.). These functional groups can help in establishing positions for modification. Based on the learning from previously published works in literature, researchers have achieved a modification of chitosan with a number of different functional groups. This work summarizes the published works of the last three years (2012–2014) regarding the modification reactions of chitosans (grafting, cross-linking, etc.) and their application to adsorption of different environmental pollutants (in liquid-phase).  相似文献   

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