共查询到19条相似文献,搜索用时 78 毫秒
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不同氨基酸螯合锌对小鼠抗氧化能力的影响 总被引:1,自引:0,他引:1
研究了三种形式锌源对小鼠抗氧化能力的影响。选用断奶小鼠(KM种)81只,随机分为三组(硫酸锌组、蛋氨酸锌组和亮氨酸锌组)。实验第一周,饲喂缺锌日粮。实验第8d起,三组饲喂加锌日粮。三种锌源均能提高肝脏、血清锌含量。补锌能使血清MDA含量明显下降,不同锌源间差异不显著(p>0.05)。补锌7d后,三种锌源提高了小鼠总抗氧化能力、总SOD、铜锌超氧化物歧化酶活性、谷胱甘肽含量,蛋氨锌组和亮氨酸锌组优于硫酸锌组酸(p<0.05)。亮氨酸锌,蛋氨酸锌的抗氧化能力优于硫酸锌,氨基酸螯合锌组之间抗氧化能力的差异不大。 相似文献
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为了探讨γ-生育三烯酚对体外培养的人结肠癌HT-29细胞的生长抑制作用,采用MTT、分裂指数、集落形成、形态学观察法测定细胞活力,Hoechst 33258荧光染色法和DNA ladder法检测检测细胞凋亡。结果表明:γ-生育三烯酚能够显著抑制HT-29细胞的增殖(P0.05),且存在剂量-效应关系,其48 h半数抑制浓度(IC 50)为35.45μmol/L;形态学观察和DNA ladder结果显示受试物能够诱导HT-29细胞凋亡。γ-生育三烯酚对人结肠癌HT-29细胞具有生长抑制作用,此作用可能与其凋亡诱导效应有关。 相似文献
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目的:研究灵芝肽(Ganoderma lucidum peptides,GLP)在体外对人肝癌HepG2细胞增殖抑制及诱导凋亡的作用。方法:HepG2细胞用含不同浓度GLP培养基培养12、24、36、48、60h,GLP分为5个浓度梯度,分别为0.25、0.5、1、2、4mg/ml,采用噻唑兰(methyl thiazolyl tetrazolium,MTT)法观察细胞生长抑制作用,用可见光显微镜、荧光显微镜观察细胞形态学变化、激光共聚焦(laser scanning confocal microscopy,LSCM)观察细胞内钙离子浓度的变化。结果:MTT法显示灵芝肽能显著抑制人肝癌HepG2细胞的生长,且存在浓度及时间依赖性。镜下可见细胞出现典型凋亡细胞形态学改变:细胞染色质浓缩,细胞体积缩小、核固缩深染、细胞膜出泡、凋亡小体形成;LSCM观察到胞内钙离子浓度明显增加。结论:0.25~4.0mg/ml的GLP体外可显著抑制人肝癌HepG2细胞增殖,存在量效关系和时效关系,能诱导人肝癌HepG2细胞凋亡,并且提示细胞内钙离子浓度的升高可能是细胞凋亡的机制之一。 相似文献
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《食品与药品》2017,(6)
目的观察凤冈锌硒茶对5株癌细胞的体外抗癌活性。方法采用煎煮法制备凤冈锌硒茶及普通绿茶水溶液,采用MTT法研究两种茶水溶液对乳腺癌细胞MCF-7、卵巢癌细胞SKOV-3、肝癌细胞SMMC-7721、肺癌细胞A549、结肠癌细胞HT29的体外增殖抑制作用;采用Hoechst 33258/PI双染法观察卵巢癌细胞SKOV-3凋亡形态。结果除结肠癌细胞外,凤冈锌硒茶水溶液对4株癌细胞48 h增殖抑制率均显著高于普通绿茶(P0.05);且72 h增殖抑制率均显著高于48 h,作用呈时间依赖性(P0.05);对卵巢癌细胞的增殖抑制率显著高于乳腺癌、肝癌、肺癌、结肠癌细胞;随着茶水溶液浓度增大,凤冈锌硒茶对卵巢癌细胞凋亡形态学影响加剧。结论凤冈锌硒茶及普通绿茶水溶液均有较强体外抗癌活性,且凤冈锌硒茶作用显著优于普通绿茶。 相似文献
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《食品工业科技》2016,(18)
乳白蛋白与油酸形成的复合物具有癌细胞生长抑制作用(Human alpha-lactalbumin made lethal to tumor cells,HAMLET)。本文制备了卵白蛋白(Ovalbumin,OVA)和油酸(Oleic acid,OA)的复合物(OVA-OA),通过检测细胞生长抑制、细胞膜通透性、细胞生长周期和凋亡的变化,分析了OVA-OA对人结肠癌细胞(Caco-2)的生长抑制作用以及其中OA对生长抑制作用的贡献。结果表明,当OVA-OA中OA的浓度达到182μmol/L时,OVA-OA对Caco-2细胞有显著(p0.05)生长抑制作用,273μmol/L时生长抑制作用增强,且随着作用时间的延长(1~3 h)而增强。在182μmol/L时,OA对Caco-2细胞也有生长抑制作用,其剂量效应关系与OVA-OA一致。但当OA浓度为273μmol/L时,其生长抑制作用弱于OVA-OA的。OVA-OA和OA均会促使乳酸脱氢酶(Lactate dehydrogenase,LDH)释放,增大晚期凋亡和坏死的细胞百分比,阻滞细胞周期在G0/G1期和S期。由此可知,OVA-OA对结肠癌细胞具有HAMLET样生长抑制作用,其中OA起主要作用。OVA-OA对人结肠癌细胞的生长抑制作用是通过损伤细胞膜、阻滞细胞生长周期和促进细胞凋亡来实现的。 相似文献
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研究水飞蓟素预处理对丙烯酰胺诱导肝细胞凋亡的抑制作用,并探讨其作用机制。以Hep G2细胞为模型细胞,设4个水飞蓟素预处理组(12,24,48,96μg/m L),预处理时间6 h,用8 mol/L丙烯酰胺染毒;同时设1个丙烯酰胺染毒组和1个细胞悬液对照组。分别采用MTT法和Annexin V-FITC双染法检测细胞活力和凋亡情况;采用细胞化学法检测细胞中Caspase-3的活性及ROS和GSH水平。结果表明,丙烯酰胺可显著增加细胞凋亡率,降低细胞存活率(P0.01)。用12~96μg/m L质量浓度范围的水飞蓟素对细胞进行预处理后,细胞凋亡率明显降低,存活率明显提高;同时细胞内ROS水平和Caspase-3的活性显著降低,细胞内GSH含量明显提高(P0.01),且在水飞蓟素质量浓度为96μg/m L时,达到最佳效果。以上说明水飞蓟素可有效抑制丙烯酰胺诱导的肝细胞凋亡,原因可能与其减缓细胞内氧化压力和抑制肝细胞凋亡途径中关键酶Caspase-3活性有密切关系。 相似文献
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BACKGROUND: Food acidulants, β‐carotene‐rich vegetables and sulfur compound‐rich Allium spices are known to improve zinc bioaccessibility from food grains. This animal study evaluated the positive influence of these promoters of zinc bioaccessibility on zinc status during zinc repletion in Wistar rats previously rendered zinc‐deficient by feeding a zinc‐deficient semi‐synthetic diet for 4 weeks. Groups of these zinc‐deficient animals were subsequently maintained on a zinc‐containing grain‐based diet for 2 weeks. Various experimental diets consisted of the grain‐based diet supplemented with (1) carrot, (2) onion, (3) amchur, (4) carrot + amchur and (5) onion + amchur. RESULTS: Zinc deficiency was confirmed by lower zinc concentration in tissues and bones and lower activity of zinc‐containing enzymes. Zinc concentration was 10–15% lower in serum, liver and kidney of zinc‐deficient rats. Bone weight in zinc‐deficient rats was 20% lower than that in normal rats. Activities of zinc‐containing enzymes (hepatic superoxide dismutase and alcohol dehydrogenase and serum alkaline phosphatase) were lower in the zinc‐deficient group. Animals fed diets supplemented with these promoters of zinc bioaccessibility showed better zinc status in tissues and bones compared with those repleted with the control stock diet. CONCLUSION: This animal study supports the claim of promoters of zinc bioaccessibility for improving zinc status, which may find practical application. Copyright © 2011 Society of Chemical Industry 相似文献
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Meika Foster Anna Chu Peter Petocz Samir Samman 《Journal of the science of food and agriculture》2013,93(10):2362-2371
Plant‐based diets contain less saturated fat and cholesterol and more folate, fibre and phytochemicals than omnivorous diets, but some micronutrients, especially zinc, are poorly bioavailable. The findings of studies exploring the zinc intake and zinc status in populations that habitually consume vegetarian diets are inconsistent. This study aims to investigate the effects of plant‐based diets on dietary zinc intake and status in humans using systematic review and meta‐analysis techniques. Thirty‐four studies were included in the systematic review. Of these, 26 studies (reporting 48 comparisons) compared males and/or females consuming vegetarian diets with non‐vegetarian groups and were included in meta‐analyses. Dietary zinc intakes and serum zinc concentrations were significantly lower (?0.88 ± 0.15 mg day?1, P < 0.001 and ?0.93 ± 0.27 µmol L?1, P = 0.001 respectively; mean ± standard error) in populations that followed habitual vegetarian diets compared with non‐vegetarians. Secondary analyses showed greater impact of vegetarian diets on the zinc intake and status of females, vegetarians from developing countries and vegans. Populations that habitually consume vegetarian diets have low zinc intakes and status. Not all vegetarian categories impact zinc status to the same extent, but a lack of consistency in defining vegetarian diets for research purposes makes dietary assessment difficult. Dietary practices that increase zinc bioavailability, the consumption of foods fortified with zinc or low‐dose supplementation are strategies that should be considered for improving the zinc status of vegetarians with low zinc intakes or serum zinc concentrations at the lower end of the reference range. © 2013 Society of Chemical Industry 相似文献
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研究了不同浓度的ZnSO4以及一定浓度的ZnSO4配合不同浓度的赤霉素GA3对麦芽富锌量的影响。结果表明,在浸麦度达到4 1 8%时用15 0mg/L的ZnSO4处理效果最好,麦芽有机锌含量是对照的2 0 3倍;当ZnSO4浓度为10 0mg/L ,赤霉素浓度为0 10mg/L时,对富锌作用促进最大,是对照的2 35倍。文中还对麦芽的富锌速度和有机锌在麦芽中的分布进行了研究。结果表明,发芽36h麦芽转化的有机锌量最多,达到36 0 0μg/ (g·d) ;蛋白质和多糖中有机锌的比例分别占总锌的6 6 %和2 3%。实验为富锌麦芽的生产提供了一定的理论基础 相似文献
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Jessie E Paterson Gwendoline F Berndt Deborah Cameron William Rowbottom 《Journal of the science of food and agriculture》1991,54(3):387-392
The response of barley to foliar and soil applied zinc was studied at fire low soil zinc sites in south-east Scotland over two season. None of the treatments increased the grain yield at harvest. Of the treatments studied only foliar applied zinc sulphate consistently increased the zinc content of plant tissue, and this was more marked when a split application of 2·5 + 2·5 kg ha?1 Zn was used as opposed to a single treatment of 5 kg ha?1 Zn. It is concluded that at the present time there is no evidence that zinc is limiting the yield potential of barley when grown on low zinc soils in this part of Scotland. 相似文献
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介绍并对比镀锌板、带、丝、棒、管以及涂塑产品锌层质量和厚度在测定中执行的不同标准、计算公式、取样量和对天平精度的要求;指出测定锌层质量和厚度的方法主要有重量法、电磁测量法、金相测量法、电化学溶解法。其中重量法由于简单易操作,不仅在国内外广泛应用,而且在仲裁试验时也常用此法。 相似文献
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锌离子在啤酒酿造中的作用与控制 总被引:1,自引:0,他引:1
啤酒中锌离子来源于麦芽、大米、酿造用水、酒花。Zn^2 在啤酒酿造过程中可起到催化荆作用,与氨基酸结合形成Zn-氨基酸螯合物。在啤酒酿造过程中,可激活酶提高酶的作用;促进糖化、发酵;促进蛋白质合成及其稳定性;缓解某金属离子的毒性作用,促进挥发物质的产生和双乙酰的还原,缩短发酵时间,提高啤酒质量;但含量过量会使啤酒非生物稳定性降低,影响啤酒质量。通过对糖化过程和发酵过程的控制,可降低醪液pH值。加入少量小麦芽,加入适量ZnCl2,ZnSO4及酵母营养盐等,可实现对Zn^2 的有效控制,达到最佳酿造浓度。 相似文献