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为比较不同品种荔枝果皮酚类物质含量、组成及其抗氧化活性差异,用80%甲醇分别提取6个品种荔枝果皮中的酚类物质,测定其总酚和总黄酮含量。采用铁离子还原能力（FRAP）和自由基离子清除能力（ABTS）等方法评价其抗氧化活性。通过高效液相色谱（HPLC）鉴定不同的单体酚并分析其在不同品种荔枝果皮之间的差异。结果表明,不同品种荔枝果皮的酚类物质含量为28.69~68.48 mg/g,不同品种荔枝果皮的酚类物质含量和抗氧化能力存在显著的差异（P<0.05）。酚类物质的含量、FRAP和ABTS抗氧化活性能力均以‘荔枝王’为最高,分别为68.48 mg/g、546.31 μmol/g和511.25 μmol/g。液相色谱结果鉴定出‘糯米糍’中的8种单体酚,而含量相对较高的是A型原花青素三聚体和原花青素A2。研究结果可为荔枝加工废弃物荔枝果皮的开发利用提供理论依据。 相似文献
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西藏不同青稞品种的品质差异分析 总被引：2，自引：0，他引：2
为了解西藏地区不同青稞品种的品质差异,采集了西藏青稞主产区的不同青稞品种,并对青稞中的水分、淀粉、粗蛋白、粗纤维、矿质元素以及有效成分总黄酮、花青素、β-葡聚糖等14项指标进行了检测。结果表明:有色青稞中淀粉和微量元素Mn、Cu、Zn的含量在年度间存在着显著的差异,且有色青稞微量元素含量普遍偏低;青稞总黄酮含量范围在0.14%~0.42%,均值为0.23%;β-葡聚糖含量范围为2.65%~6.52%,均值为4.59%;有色青稞花青素含量变化较大,范围在0.022 7~0.649 7 mg/g,均值为0.133 2 mg/g。总黄酮含量、β-葡聚糖含量年际间差异不大,花青素含量年际间差异巨大。总黄酮含量有色青稞显著高于普通青稞,而β-葡聚糖含量二者无显著差异。 相似文献
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分析了我国不同产区不同品种亚麻籽的组成及体外抗氧化特性。结果表明,除基本组成成分外,不同品种亚麻籽主要活性组分含量和体外抗氧化活性具有显著差异。α-亚麻酸、木酚素、总酚酸、黄酮、生育酚、植物甾醇含量范围分别为33.42%~59.74%,120~918 mg/100g,209~491 mg/100g,33.04~75.63 mg/100g,8.68~20.75 mg/100g,340~596 mg/100g。亚麻籽提取物DPPH值和FRAP值分别为4 357~8 146 μmol Trolox/100g, 8 289~15058 μmol Trolox/100g。此外,不同品种亚麻籽抗营养因子生氰糖苷含量差异较为显著(5.57~11.34 mg HCN/100g)。相关性分析结果表明,亚麻籽提取物体外抗氧化活性与木酚素、总酚酸和黄酮含量具有显著相关性（p<0.05）。主成分分析和聚类分析结果表明,亚麻籽主要酚类化合物及其抗氧化活性主要依赖于亚麻籽品种特性,而非种植区域。 相似文献
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为研究光照对青稞萌发过程中功能成分的影响,以隆子黑青稞为材料,采用酶联免疫吸附法和分光光度计法测定了不同光照时间处理下黑青稞萌发过程中褪黑素、总酚和总黄酮含量及其抗氧化活性;同时测定了黑青稞发芽率、胚根和胚芽长度,并对避光萌发5 d的芽苗进行了感官评定。结果表明,随萌发时间的延长,青稞芽苗中褪黑素、总酚和总黄酮含量与种子相比均显著增加,且不同光照时间下芽苗中各被测指标增幅有显著性差异。避光条件下萌发5 d时芽苗的褪黑素含量最高,为13.11 ng·g-1 ,是种子的2.2倍;避光萌发第7天时芽苗中总酚和总黄酮含量最高,分别为842.81±3.33和157.31±0.53 mg·100 g-1,是种子的2.8倍和3.9倍。抗氧化活性因为测定方法的不同略有差异,但不同光照时间均增加了种子抗氧化活性,避光萌发第7天,芽苗中FRAP、DPPH自由基和ABTS自由基清除能力最大,分别是种子的3.2倍、4.9倍和 4.6倍;羟自由基清除能力在避光萌发第5天达到最大,是种子的8.0倍。黑青稞发芽率和胚芽长不受光照时间的影响,避光处理下胚根平均长度最长;避光萌发5 d的黑青稞芽苗感官评定整体可接受性为7级-中等喜欢。综上,避光萌发显著增加了黑青稞活性成分含量和抗氧化活性,为黑青稞相关功能产品的开发提供了数据支撑和理论参考。 相似文献
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产地及品种对西藏青稞营养品质的影响 总被引：1，自引：0，他引：1
为了明确产地和品种对西藏青稞营养品质的影响,对采自西藏6个地(市)、26个县的7个普通青稞品种和3个有色青稞品种(257份样品)的5个品质指标和8种矿质元素含量进行了分析。结果表明,(1)产地生态条件是影响青稞品质和矿质元素含量的首要因素,产地对普通青稞的10个被测指标有显著影响;品种对普通青稞的5种被测指标有显著影响;产地和品种的交互作用显著影响5个被测矿质元素含量;产地显著影响有色青稞的黄酮、粗蛋白和磷含量。(2)青稞不同品质指标和矿质元素含量变异程度不同,变异系数最高为52.3%。供试青稞粗淀粉含量为46.64%~53.76%,粗蛋白含量为6.51%~14.21%,粗纤维含量为1.66%~3.4%,β-葡聚糖含量为3.63%~5.13%,黄酮含量为0.18%~0.40%;钾含量为4 224.8~7 646.5mg·kg~(-1),磷含量为2 243.1~6 288.7mg·kg~(-1),镁含量为731.6~1 572.0mg·kg~(-1),钙含量为246.4~789.0mg·kg~(-1),铁含量为27.59~173.99mg·kg~(-1),锌含量为17.56~85.22mg·kg~(-1),锰含量为10.42~22.23mg·kg~(-1),铜含量为2.12~11.84mg·kg~(-1)。(3)有色青稞的粗淀粉和黄酮含量显著高于普通青稞,而粗蛋白和粗纤维含量显著低于普通青稞,β-葡聚糖含量二者间无显著差异。 相似文献
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本文建立了采用高效液相色谱法同时检测火麻籽油中10种酚类物质的方法,10种单体酚检出限为0.05～0.12μg/mL,线性相关系数为0.9970～0.9998,回收率为85%～108%。检测了8份不同产地火麻籽油的总酚、总黄酮含量及体外抗氧化活性指标（DPPH、FRAP、ABTS+·）。总酚含量为1.20～17.35mg对香豆酸/100g,总黄酮含量为7.61～51.72mg柚皮苷/100g。DPPH清除能力为9.03～19.71mmol TE/100g,FRAP还原能力为13.12～30.09mmol TE/100g,ABTS+•清除能力为29.40～358.37mmol TE/100g。相关性分析表明,总酚含量与DPPH、ABTS+•清除能力和FRAP还原能力呈显著正相关;总黄酮含量与DPPH清除能力、FRAP的还原能力呈显著正相关。 相似文献
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为了解青稞籽粒长、宽在品种(系)间的差异,以来自国内外的214份青稞品种(系)为材料,对粒长、粒宽进行鉴定分析。结果表明,青稞粒长、粒宽在品种(系)间均存在显著差异。粒长的变异范围为4.125～8.117 mm,平均值6.075 mm,总变异系数10.906%;籽粒较长的材料有北青2号(青海海北)、长芒裸大麦(云南昆明)、白青稞(西藏隆子)、山青7号(西藏山南)和喜马拉4号(西藏仁布),以喜马拉4号最长;籽粒较短的材料有湟中六棱青稞(青海湟中)、扎骨(西藏左贡)、褐青稞(青海)、米大麦(云南晋宁)和米如红(西藏南木林),以湟中六棱青稞最短。粒宽变异范围为1.670～3.553 mm,平均值2.596 mm,总变异系数13.721%;籽粒较窄材料有米如红(西藏南木林)、白青稞(西藏昌都)、丹巴黑青稞(四川丹巴)、冬207(西藏拉萨)和白青稞(西藏隆子),其中最窄品种为米如红;较宽材料为Bang-Iu(墨西哥)、紫青稞(西藏穷结)、繁29(青海)和喜马拉6号(西藏日喀则),最宽材料为喜马拉6号。从材料来源看,青稞粒长在不同地区间也差异显著,但粒宽差异不显著;甘肃材料的粒长平均值最大(6.2... 相似文献
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为探究甘肃酒泉产甜叶菊中总黄酮提取条件、成分与其抗氧化活性间的关系。采用乙醇超声水浴提取法,探讨提取时间、温度、料液比、功率等因素对总黄酮提取条件的影响;用HPLC柠檬酸-甲醇流动相梯度洗脱法测定甜叶菊中芦丁、圣草枸杞苷、山奈素、槲皮素、橙皮苷的含量;用FRPD和DPPH法评价甜叶菊茎叶中总黄酮提取物与抗氧化活性之间的关系。结果:通过正交试验,得出乙醇超声水浴的最佳提取条件:80%乙醇、提取功率450 W、料液比1∶20、提取时间150 min、温度85℃、提取3次,总黄酮提取率最高可达到0.88%;HPLC法检测甜叶菊茎叶中5种黄酮成分,以芦丁的含量(701.42μg/g)为最高,槲皮素含量(451.55μg/g)居其次,橙皮苷含量(297.54μg/g)与山奈素含量(241.21μg/g)较少,圣草枸杞苷含量(57.44μg/g)极微;用FRPD和DPPH法评价甜叶菊茎叶总黄酮提取物抗氧化活性,其抗氧化活性高达10.02 mg/g DW,黄酮含量与抗氧化活性二者呈较显著的正相关性(R=0.769～0.792)。这为甜叶菊中黄酮类物质的提取与进一步开发利用提供基础性研究资料。 相似文献
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干燥方式对澳洲坚果青皮酚类物质提取量及抗氧化活性的影响 总被引：1，自引：0，他引：1
本研究以新鲜澳洲坚果青皮为对照组,研究60℃热风干燥、微波干燥及真空冷冻干燥对澳洲坚果青皮总酚、总黄酮提取量及抗氧化活性的影响。结果表明:与对照组相比,不同干燥处理对澳洲坚果青皮总酚、总黄酮提取量及抗氧化活性均有影响,真空冷冻干燥处理对其影响最小,总酚提取量、总黄酮提取量分别为935.61、995.75 mg/hg,DPPH自由基、ABTS自由基半数清除率IC50分别为6.83、63.84 mg/L,总抗氧化能力约为Trolox的1.74倍;不同干燥处理后,澳洲坚果青皮总酚、总黄酮提取量及抗氧化活性存在显著性差异（p<0.05）。相关性分析结果表明:不同干燥处理后抗氧化活性与总酚、总黄酮提取量显著相关（p<0.05）。因此,与60℃热风干燥、微波干燥相比,真空冷冻干燥能较好的保留澳洲坚果青皮中酚类物质,并具有较强抗氧化活性,适于澳洲坚果青皮干燥处理。 相似文献
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Systemic and asymptomatic Neotyphodium fungal endophytes infect numerous species of the Poaceae. The frequencies of Neotyphodium endophyte infection in Finland were investigated among and within seven Nordic cultivars of meadow fescue, Schedonorus pratensis (Huds.) P. Beauv., which is a widely grown pasture and forage grass species in Scandinavia. The cultivars were Kasper, Salten, Antti, Fure, Ilmari, Inkeri and Kalevi. Frequencies of infection of cultivars varied from endophyte-free cultivar Fure to highly infected cultivar Inkeri [mean (standard deviation of mean) of 0·95 (0·023)]. Mean frequencies of infection of three cultivars remained lower than 0·10, and two of the cultivars, Kasper and Salten, were intermediately infected. In most of the cultivars, frequencies of infection varied only slightly among seed lots. In cultivar Kasper, however, the frequency of endophyte infection was highly variable (0–0·96) among the 45 seed lots examined. The relative importance of cultivar, seed lot and infection by Neotyphodium endophyte to the aphid Rhopalosiphum padi L. was studied experimentally, using both endophyte-free and endophyte-infected plants of four seed lots of the two intermediately infected cultivars. Endophyte infection increased plant resistance to R. padi , overriding the influences of seed lot and cultivar. It is proposed that variation caused by endophyte infections in cultivars of meadow fescue should be taken into account in assessing plant breeding programmes in Europe. 相似文献
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Quynh-Hoa Pham Xuan-An Tran Thi-Nha-Trang Nguyen Thi-Thuy-Anh Tran Hai-Yen Hoang Thi-Hong-Van Nguyen Thi-Hanh Tang Thi-Phuc Do 《水稻科学》2016,23(6):334
Rice(Oryza sativa) is sensitive to salinity, but the salt tolerance level differs among cultivars, which might result from natural variations in the genes that are responsible for salt tolerance. High-affinity potassium transporter(HKTs) has been proven to be involved in salt tolerance in plants. Therefore, we screened for natural nucleotide polymorphism in the coding sequence of Os HKT1, which encodes the HKT protein in eight Vietnamese rice cultivars differing in salt tolerance level. In total, seven nucleotide substitutions in coding sequence of Os HKT1 were found, including two non-synonymous and five synonymous substitutions. Further analysis revealed that these two non-synonymous nucleotide substitutions(G50T and T1209A) caused changes in amino acids(Gly17Val and Asp403Glu) at signal peptide and the loop of the sixth transmembrane domain, respectively. To assess the potential effect of these substitutions on the protein function, the 3D structure of HKT protein variants was modelled by using PHYRE2 webserver. The results showed that no difference was observed when compared those predicted 3D structure of HKT protein variants with each other. In addition, the codon bias of synonymous substitutions cannot clearly show correlation with salt tolerance level. It might be interesting to further investigate the functional roles of detected non-synonymous substitutions as it might correlate to salt tolerance in rice. 相似文献
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Russell Pressey 《American Journal of Potato Research》1969,46(8):291-297
Freshly harvested potatoes contain low levels of total invertase and high levels of invertase inhibitor. Total invertase increases sharply when potatoes are placed in cold storage, but the inhibitor is not depleted in all varieties. The absence of basal invertase activity in Norchip tubers indicates that an excess of invertase is not required for reducing sugar formation. Analyses of 37 varieties and seedlings after 3 months cold storage revealed that the reducing sugar content is not proportional to the invertase activity. High sugar contents are associated with low inhibitor levels, but low sugars are not necessarily associated with high inhibitor levels. The results indicate that invertase participates in reducing sugar formation, but other factors are responsible for the regulation of starch-sugar conversion in potatoes during cold storage. 相似文献
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马铃薯试管苗组织培养及微型薯诱导技术的研究 总被引：9，自引：2，他引：9
通过加入不同浓度的BA、NAA和KT,以探讨外源激素对马铃薯试管苗生理性状的影响,发现低浓度的外源激素较适合用来进行试管苗的增殖。本试验利用香豆素进行微型薯的诱导,结果表明低浓度的香豆素对提高薯重和大薯率有利,而高浓度有利于提高微型薯的结薯数量。 相似文献
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Soomro MT Zahir E Mohiuddin S Khan AN Naqvi II 《Pakistan journal of biological sciences: PJBS》2008,11(2):285-289
In present study, Mn, Fe, Zn, Cu, Co, Pb, Cr, Ni and Cd were analyzed by FAAS in green and black tea samples of locally available in the Pakistani market. Na and K were also determined by Flame Photometer. Tea leaves can be the source of mineral components and trace elements, as well as some undesirable substances due to exposure to the environment. Among the metals tested, K was the most abundant one followed by Na, Mn and Fe. Fortunately, toxic heavy metals, Pb and Cd, had the lowest contents in tea samples and also in tea aqueous extracts. Concentration of heavy metals in tea aqueous extract was markedly lower than their total contents except that of K. The solubility of studied metals in tea aqueous extract varied widely and ranged from 0.0-95%. The lowest ranges of solubility were listed for toxic heavy metals Pb and Cd. The possible uptake of metals by the human body from tea aqueous extract has also been determined. The amounts of metals that one may take up through consumption of tea aqueous extract were found to match the acceptable daily intake even taking into account exposure from air, food and drinking water. 相似文献
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我国发展能源油料作物的策略分析 总被引：10，自引：5，他引：5
分析了国内外植物油脂的供需形势、我国耕地和边际地利用潜力、油脂植物资源的种属分布特点等,提出发展我国能源油料作物和生物柴油产业的3点建议：加大对边际地、油脂植物资源的调查等基础平台性研究,为政府决策和产业服务;加强产学研结合,形成研究、推广、产业的良性循环;制定能源植物推广应用优惠政策、推动能源油料作物生产发展。 相似文献