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1.
为优化西瓜中番茄红素微波辅助提取工艺,明确番茄红素的抗氧化活性,以番茄红素提取量为指标,通过单因素结合正交试验优化西瓜中番茄红素微波辅助提取工艺条件,并以BHT为阳性对照,利用清除DPPH·法和·OH法评价西瓜番茄红素的抗氧化活性。结果表明,微波辅助提取西瓜中番茄红素最佳工艺条件为:以体积比7∶1的乙酸乙酯-丙酮混合溶液为提取剂,微波功率260 W,微波时间60 s,料液比1∶12(g/mL),提取次数2次。此工艺条件下,西瓜中番茄红素的提取量为1.602 mg/g。西瓜番茄红素与BHT清除DPPH·的IC_(50)分别为8.95μg/mL与20.36μg/mL;清除·OH的IC_(50)分别为4.44μg/mL与10.44μg/mL,表明西瓜番茄红素具有很强的抗氧化活性。 相似文献
2.
藤三七总黄酮的超声波辅助提取及其抗氧化性研究 总被引：1，自引：0，他引：1
以藤三七为原料,采用超声波辅助提取总黄酮,利用正交试验优化其提取工艺,并从清除羟基自由基(·OH)、1,1-苯基-2-苦基肼自由基(DPPH·)和超氧阴离子自由基(O2-·)的能力3个角度评价其抗氧化性。结果表明,超声波辅助提取藤三七总黄酮的最佳提取工艺为:乙醇体积分数80%,液料比40∶1(m L/g),超声时间60 min,超声温度40℃。在该条件下,总黄酮平均提取率为18.51%。超声波辅助提取的总黄酮具有较强的抗氧化性,对·OH、DPPH·、O2-·清除作用明显,且其质量浓度与抗氧化活性呈量效关系,是一种良好的天然抗氧化剂。 相似文献
3.
应用响应面法对超声波辅助提取黄瓜皮多酚的工艺进行优化,并对多酚的抗氧化活性进行了研究。以多酚提取率为响应值,选取超声温度、乙醇浓度、液料比、超声时间为自变量,应用Box-Behnken对试验进行设计和响应面优化,并通过多酚对羟自由基(·OH)和1,1-二苯基-2-三硝基苯肼自由基(DPPH·)的清除效果来评价其抗氧化活性。结果表明,黄瓜皮多酚的最佳提取工艺为:超声温度65℃,乙醇浓度62%,液料比26∶1(mL/g),超声时间31 min。在此条件下,测得多酚提取率实际值为(10.29±0.14)mg/g,理论值和实际值相对误差是0.39%,由此可以说明应用响应面法所得到的提取工艺参数可行性强、可靠性高。黄瓜皮多酚对·OH和DPPH·清除率的IC50值分别为116.60 mg/L和57.41 mg/L,表明黄瓜皮多酚具有较好的抗氧化活性,且抗氧化活性与多酚浓度呈正相关,该研究为将黄瓜皮多酚开发成天然抗氧剂提供理论基础。 相似文献
4.
以菊芋叶为原料,以料液比、乙醇浓度、超声时间、超声功率为考察因素,在单因素试验的基础上,通过响应面设计优化菊芋叶多酚的提取工艺,并探究菊芋叶多酚的体外抗氧化活性.结果表明,菊芋叶多酚的最佳提取条件为:料液比1:20(g/mL),乙醇浓度50％,超声时间50 min,超声波功率500 W,在该条件下多酚得率为31.923 mg/g.抗氧化试验表明:菊芋叶多酚具有明显的抗氧化活性,对DPPH自由基(DPPH·)、羟基自由基(·OH)和超氧阴离子自由基(O2·)有较好的清除能力;与VC的抗氧化活性相比,菊芋叶多酚对O2·的清除作用明显高于VC. 相似文献
5.
6.
研究了超声波辅助乙醇溶剂法萃取荔枝核黄酮的工艺条件。在单因素试验基础上,采用BoxBehnken设计进行响应面优化分析,建立回归方程模型,模型决定系数R2=0.985 0。结果表明,优化的最佳工艺参数为:液料比12.7∶1(g/g),超声时间14.7 min,提取时间120 min,超声波功率174 W,乙醇体积分数55%。该工艺条件下,荔枝核黄酮提取实际得率均值为6.565 6%。荔枝核黄酮具有较强的自由基清除能力,其清除·OH和DPPH·的IC50分别为5.938μg·m L~(-1)和8.571μg·m L~(-1)。 相似文献
7.
黑枸杞总黄酮微波辅助提取及其抗氧化活性研究 总被引：2，自引：0，他引：2
以总黄酮提取率为考察指标,通过单因素试验与正交试验,研究了影响黑枸杞总黄酮微波辅助提取的因素条件,优化了提取工艺,同时以2,6-二叔丁基对甲酚(BHT)为阳性对照,利用1,1-二苯基-2-三硝基苯肼自由基(DPPH·)与羟基自由基(·OH)清除法评价黑枸杞总黄酮的抗氧化活性。结果表明,乙醇浓度对黑枸杞总黄酮微波辅助提取有显著影响,黑枸杞总黄酮最佳提取工艺条件为:60%乙醇为提取剂,料液比1∶25(g/m L),微波时间14 min,微波功率325 W。该提取工艺条件下,黑枸杞总黄酮提取率为4.35%。黑枸杞总黄酮与BHT对DPPH·的IC50分别为0.64 mg/m L和1.30 mg/m L,对·OH的IC50分别为0.40 mg/m L和1.68 mg/m L,表明黑枸杞总黄酮具有很强的抗氧化活性。 相似文献
8.
优化马齿苋中总黄酮的甲醇浸提-超声波辅助提取最佳工艺，并评价其体外抗氧化、抗肿瘤活性。以甲醇浓度、提取温度、料液比和超声功率为因素，以总黄酮提取率为指标，通过单因素试验与正交设计优选马齿苋总黄酮的超声波辅助提取条件；测定其对DPPH?和?OH的清除能力评价抗氧化活性；MTT法测定其对人肺癌细胞A549体外增殖的影响。结果表明：马齿苋总黄酮的最佳提取工艺为：料液比1:50，温度80℃，超声功率200 W，甲醇浓度90%，提取30 min，提取2次，总黄酮提取率为6.37%。马齿苋总黄酮对DPPH?清除率在4.0 mg/mL为89.80%，对?OH清除率在20.0 mg/mL为86.07%；其质量浓度为420 μg/mL时对细胞A549增殖的抑制率为74.62%，与阳性药组无显著性差异。该优化工艺准确可靠，提取率高；马齿苋总黄酮具有较强的抗氧化和抗肿瘤活性。 相似文献
9.
旨在优化商洛天麻多糖的提取工艺并分析其抗氧化活性。本研究以商洛市天麻为材料,通过正交试验对超声辅助热水浸提法提取天麻多糖的工艺进行优化,并测定其DPPH自由基和羟基自由基的清除能力,以分析其抗氧化活性。结果表明,超声波辅助热水浸提法提取天麻多糖的最佳工艺条件为提取温度65℃,提取时间45 min,料液比1:40 g/mL,该条件下商洛天麻多糖含量为32.83 mg/g。天麻多糖清除DPPH自由基及羟基自由基的能力随浓度的增大而升高,说明天麻多糖含量在一定范围内有良好的清除DPPH自由基及羟基自由基的效果。当浓度3.5 mg/mL时,天麻多糖对DPPH自由基清除率能达到40.52%,羟基自由基的清除率能达到36.52%。天麻多糖具有开发成抗氧化剂的潜力。 相似文献
10.
采用超声联合酶法提取紫花苜蓿总黄酮,利用响应面法对该提取工艺进行优化,并对其提取物进行体外抗氧化活性研究。结果表明,超声联合酶法提取紫花苜蓿总黄酮的最佳工艺为:液料比40:1,超声时间为55min,超声温度为60℃,在此条件下紫花苜蓿总黄酮的提取率达9.928mg/g,与理论值的相对误差为0.40%,相比于其他传统方法,提取量大大提高;此外,紫花苜蓿总黄酮拥有良好的清除DPPH和·OH自由基的能力,其半数清除浓度(IC50)分别为14.31μg/mL及28.23μg/mL。 相似文献
11.
Jens Jensen 《Euphytica》1979,28(1):47-56
Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans. 相似文献
12.
G. H. Kroon 《Euphytica》1994,76(1-2):125-125
Summary
K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes. 相似文献
13.
Hongyan WEI Jian ZHOU Jinguang LU Jingzheng SONG Qiongxi YU Zhihong JIANG 《Medicinal Plant》2019,(6):27-29
[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol... 相似文献
14.
Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed. 相似文献
15.
Mohammed Riyazaddin Polavarapu B. Kavi Kishor Are Ashok Kumar Belum V. S. Reddy Rajendra S. Munghate Hari C. Sharma 《Plant Breeding》2015,134(4):423-436
Sorghum shoot fly, Atherigona soccata, is one of the important pests of postrainy season sorghums. Of the 90 sorghum genotypes evaluated for resistance to this pest, RHRB 12, ICSV 713, 25026, 93046 and 25027, IS 33844‐5, Giddi Maldandi and RVRT 3 exhibited resistance in postrainy season, while ICSB 463, Phule Anuradha, RHRB 19, Parbhani Moti, ICSV 705, PS 35805, IS 5480, 5622, 17726, 18368 and 34722, RVRT 1, ICSR 93031 and Dagidi Solapur showed resistance in rainy season, suggesting season‐specific expression of resistance to A. soccata. ICSB 461, ICSB 463, Phule Yasodha, M 35‐1, ICSV 700, 711, 25010, 25019 and 93089, IS 18662, Phule Vasudha, IS 18551 and 33844‐5 and Barsizoot had fewer deadhearts than plants with eggs across seasons, suggesting antibiosis as one of the resistance mechanism. Five genotypes exhibited resistance with high grain yield across seasons. Correlation, path and stepwise regression analyses indicated that leaf glossiness, seedling vigour, trichome density, oviposition and leaf sheath pigmentation were associated with the expression of resistance/susceptibility to shoot fly, and these can be used as marker traits to select and develop shoot fly‐resistant sorghums. 相似文献
16.
Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed. 相似文献
17.
Summary
Hordeum chilense is a wild barley extensively used in wide crosses in the Triticeae. It could be a valuable source of resistance to Fusarium culmorum and Septoria nodorum. Some H. chilense x Triticum spp. amphiploids, named tritordeums, were more resistant than the parental wheat line to these diseases, others were not. Average contents of ergosterol and deoxynivalenol (DON) suggested that resistance to colonization by Fusarium was the highest for Hordeum chilense, followed by tritordeum and wheat in decreasing order. In particular, the H. chilense genotypes H7 and H17 enhanced the wheat resistance to F. culmorum in its tritordeum offsprings. Resistance to S. nodorum in tritordeum was not associated with tall plant height. There is sufficient genetic variation for resistance to F. culmorum and S. nodorum among tritordeum to allow the breeding of lines combining short straw and resistance to both diseases. 相似文献
18.
J. T. Fletcher 《Euphytica》1992,63(1-2):33-49
Summary Cultivars of tomatoes, cucumbers, lettuce and peppers have been bred for resistance to one or more pathogens. Some tomato and cucumber cultivars have resistance to a wide range of diseases. Resistance has been transient in many cases and a succession of cultivars with new genes or new combinations of resistance genes has been necessary to maintain control. There has been a number of notable exceptions and these have included durable resistance to such pathogens asFulvia fulva and tomato mosaic virus. With lettuce the resistance situation is complicated by the occurrence of fungicide resistant pathotypes. There are no strains ofAgaricus bisporus purposely bred for disease resistance.In protected flower crops only resistance to Fusarium wilt in carnations has been purposely bred but differences in disease resistance are apparent in cultivars of many ornamental crops. This is particularly so in chrysanthemums where there are cultivars with resistance to many of the major pathogens. Similar situations occur with other flower crops and pot plants. Cultivars of some species have not been systematically investigated for resistance.The need for genetic resistance will increase with the further reduction, in the limits on pesticide use and an increasing public awareness and importance of pesticide pollution.ADAS is an executive agency of the Ministry of Agiculture, Fisheries and Food and the Welsh Office. 相似文献
19.
M. Raj Ahuja 《Euphytica》2009,165(1):5-19
The genetic constitution and diversity of four relictual redwoods are discussed in this review. These include monotypic genera
of the family Cupressaceae: coast redwood (Sequoia sempervirens), giant sequoia (Sequoiadendron giganteum), dawn redwood (Metasequoia glyptostroboides), and alerce (Fitzroya cupressoides). All four species are narrow endemics, share a number of common phenotypic traits, including red wood, and are threatened
species. Fossil history suggests that the ancestors of redwoods probably originated during the Cretaceous and Tertiary periods
and flourished thereafter for millions of years. Towards the end of the Tertiary period began their decline and struggle for
existence that continued during the subsequent geologic upheavals and climate changes, until the survival of the present-day
redwoods in the current restricted locations in the world (USA, China, and South America). Although two species, Sequoiadendron and Metasequoia, are diploids (2n = 22), and the other two are polyploids: Fitzroya a tetraploid (2n = 4x = 44), and Sequoia a hexaploid (2n = 6x = 66); they all share the same basic chromosome number x = 11. The genome size in the hexaploid Sequoia is one of the largest (31,500 MB) in the conifers, while the genome sizes of diploid Metasequoia and Sequoiadendron are about one-third (~10,000 MB) of Sequoia. Genetic diversity in the redwoods is lower than most other gymnosperms, except in Sequoia, which seems to rank near the upper quarter of the coniferous forest trees. Genomic research is sparse in the redwoods, and
should be pursued for a better understanding of their genome structure, function, and adaptive genetic diversity. 相似文献
20.
The induction in vitro of adventitious shoots in Rosa 总被引：8，自引：0，他引：8
Summary Adventitious shoots were formed on excised leaves, roots and callus of Rosa persica x xanthina and on excised leaves of R. laevigata and R. wichuraiana on culture media that included BAP and NAA as growth regulators. Shoots formed freely on freshly cultured callus of R. persica x xanthina but their production declined in successive cultures and ceased after twelve weeks. Transplantation to soil was improved by rooting plantlets in cellulose plugs in vitro and transferring plantlets to soil while still in the plugs. 相似文献