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儿茶素是茶叶的主要功能成分,本试验探讨了乙醇浸提、硫酸-香荚兰素比色法检测绿茶面包中儿茶素含量的可行性.选择95％乙醇溶液作为提取溶剂,采用3因素3水平正交试验设计方案,考察料液比、浸提温度、浸提时间对绿茶面包中儿茶素总量提取效果的影响,并对硫酸-香荚兰素比色法检测绿茶面包中儿茶素含量进行了方法学考察.结果表明,绿茶面包中儿茶素总量检测的最佳浸提条件为:料液比1:20(g·mL-1),70℃水浴浸提45 min;硫酸-香荚兰素比色方法为:取0.5 mL浸提液,加入2.5 mL1％的香荚兰素/乙醇溶液和2.5 mL30％的硫酸/乙醇溶液,在20℃下反应10～30 min,取反应液在500 nm处测定吸光度.本方法中儿茶素浓度在0.025～0.3 mg·mL-1范围内,吸光度与浓度线性关系良好(R2=0.9996),同一样品重复测定6次的RSD为1.31％,儿茶素高、中、低浓度加标回收率范围在98.75％～103.25％,本方法满足绿茶面包中儿茶素总量的检测分析,儿茶素含量可作为标定绿茶面包中茶叶添加量的评价指标. 相似文献
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在石斛兰组织培养中,以茎尖、叶尖为外植体,在附加2,4—D0.15～0.5毫克/升、BA0.5毫克/升的MS培养基上,其分化率可达1:10左右。分化的幼芽转至含有活性碳、椰乳的MS培养基中(附加2,4—D和BA各0.1毫克/升),即能正常生长形成无根幼苗。将幼苗转入含有IBA0.2～0.4毫克/升的MS培养基中,能够诱导生根,形成具有根、茎、叶的完整小植株。 相似文献
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对无土栽培香荚兰叶片的营养状况进行测试分析。结果表明：施用不同配方营养液的香荚兰各养分含量也不同。施用A3营养液和对照A5的香荚兰叶片N素含量在适宜范围内，而施用A1、A2和A4营养液的香荚兰叶片N素缺乏；除施用对照A5的香荚兰叶片K素缺乏外，施用其余4种营养液配方K素存在高量；施用所有配方营养液的香荚兰叶片的P素、Ca素和Mg素均为缺乏，其中Ca、Mg缺乏非常严重。各营养液配方下的香荚兰叶片养分之间比例严重失衡。从养分含量方面分析，以A3营养液配方为基础，进行营养液配方调整比较适宜；从养分平衡状况来看， 相似文献
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以野生黄精不定芽为材料,以MS为基本培养基,添加不同浓度的植物生长调节剂6-BA、2,4-D、NAA、KT进行3因素4水平的正交设计试验,筛选黄精增殖的最佳培养条件;探讨不同培养温度对黄精组培苗继代增殖的影响;以1/2 MS为基本培养基,探讨不同生长素及其浓度和不同培养容器对组培苗生根的影响。结果表明,黄精组培苗最佳继代增殖培养基为MS + 2.0 mg/L 6-BA + 0.2 mg/L 2,4-D + 0.4 mg/L NAA,最佳培养温度为22 ℃,平均繁殖系数达6.88;最佳生根培养基为1/2 MS + 0.5 mg/L NAA + 0.2 mg/L IBA,平均生根率达96.2%;接种袋是黄精工厂化育苗的首选生根培养容器。 相似文献
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外源IBA对裸花紫珠扦插生根和内源激素含量变化的影响 总被引：1，自引：0，他引：1
以药用植物裸花紫珠(Callicarpa nudiflora)1年生半木质化枝条为材料,采用吲哚丁酸(IBA)5个浓度(0、1 000、1 500、2 000、2 500 mg/L)处理。每隔6 d从1 500 mg/L IBA浓度与对照处理插穗的基部取样1次,测定在生根过程中内源吲哚乙酸(IAA)、脱落酸(ABA)、赤霉素(GA3)、玉米素核苷(ZR)含量的变化。扦插80 d后,采用隶属函数法综合评价生根效果。结果表明:不同IBA浓度处理对插穗生根影响差异显著。与对照相比,IBA处理不同程度地提高了插穗的生根率、平均生根数、最长根长和平均根长,降低了偏根率。其中,以1 500 mg/L IBA处理生根效果最好,其生根率、根体积最大,综合评价指数最高。在裸花紫珠插穗根原基诱导和愈伤组织形成阶段,1 500 mg/L IBA处理可提高插穗基部IAA和GA3含量,降低ABA和ZR含量,IAA/ABA和IAA/ZR比值迅速升高。在不定根形成、发生及生长发育阶段,IAA含量下降,IAA/ABA和IAA/ZR比值逐渐降低。较低的内源ABA、ZR含量和较高的IAA、GA3含量及IAA/ABA、IAA/ZR比值,有利于裸花紫珠插穗半木质化插穗不定根的形成和发育。 相似文献
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以五指山野生的1～2年生的山苦茶木质化枝条为扦插材料,利用不同浓度(100、400、800 mg/L)的根旺、IBA、NAA、IAA浸泡3类插穗(长度都约为10 cm,直径分别为0.20～0.40、0.45～0.70、0.75～1.00 cm)基部,时间为0.5、2.0、8.0 h;扦插基质为河沙。结果表明,不同处理间扦插生根率和生根数与对照组相比,均存在显著差异,以直径为0.45～0.70 cm的插穗的插条的生根效果最好;单一生长调节剂的处理中,以根旺及IBA的效果最好,生根率达到50%以上;不同浓度的生长调节剂处理中以800 mg/L的IBA效果最好,生根率达到60%,生根条数13条;3种处理时间中以0.5 h的生根效果最好。 相似文献
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用５种培养液：１／２ＭＳ，１／２ＭＳ＋ＩＡＡ，１／２ＭＳ＋ＰＰ３３３＋ＩＡＡ，ＡＢＴ１号生根粉及对照，作香荚兰蔓段秀导不定根发生和生长试验。经２０ｄ培养，１／２ＭＳ＋ＰＰ３３３＋ＩＡＡ培养液诱导不定根发生率最高，新根生长最好，试验观察到，ＰＰ３３３和ＩＡＡ在一定浓度配比下，对香荚兰有明显诱导生根作用。 相似文献
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香草兰果荚发育中存在严重的果荚脱落现象,对香草兰果荚脱落情况及其內源激素含量变化进行探讨,以期解决目前生产上果荚脱落率高的问题。设疏果后保留1个、8~10个香草兰果荚以及未疏果共3种处理,从果荚发育至脱落的60 d内分期取材,采用酶联免疫法分别测定各处理果荚中生长素(IAA)、赤霉素(GA)、玉米素核苷(ZR)和脱落酸(ABA)的含量。结果表明:3种处理的果荚脱落率与保留果荚数目呈正相关;IAA和ZR的含量在前期较高,ABA的含量在中、后期较高,GA的含量一直维持在较低的水平;较高的IAA/ABA和(IAA+GA+ZR)/ABA比值有利于控制果荚脱落;疏果处理有利于坐果的激素平衡,而保留过多的果荚则不利于形成激素平衡。本研究可为解决生产中的香草兰落荚问题提供理论依据和技术方法。 相似文献
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《Journal of Crop Improvement》2013,27(2):81-114
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
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Lakshman Lal 《Potato Research》1987,30(2):329-334
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
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Joseph E. Laferriere Charles W. Weber Edwin A. Kohlhepp 《Plant foods for human nutrition (Dordrecht, Netherlands)》1991,41(3):277-282
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described. 相似文献
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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
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M. I. Siri P. Villanueva M. J. Pianzzola L. Franco Fraguas G. Galván M. Acosta F. Ferreira 《Potato Research》2004,47(3-4):127-138
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
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Alejandro Carlos Tozzini María Fernanda Ceriani María Verónica Saladrigas H. Esteban Hopp 《Potato Research》1991,34(3):317-324
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
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Rita Favas Janaína Morone Rosrio Martins Vitor Vasconcelos Graciliana Lopes 《Marine drugs》2022,20(3)
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
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Alejandro M. S. Mayer Abimael D. Rodríguez Orazio Taglialatela-Scafati Nobuhiro Fusetani 《Marine drugs》2013,11(7):2510-2573
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