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1.
To investigate the effects of dietary quercetin on growth, antioxidation, and flesh quality of grass carp, Ctenopharyngodon idella, six diets were prepared with quercetin inclusion rates of 0 (control diet), 0.1, 0.2, 0.4, 0.6, and 0.8 g/kg. Grass carp with a body weight of 13.3 ± 0.1 g were fed with one of the six diets for 60 days. The weight gain (WG) showed a quadratic relationship with dietary quercetin levels; the supplementation of 0.4 g/kg quercetin significantly improved WG (+4.73%) and decreased feed conversion ratio (?0.06) (p < .05) when compared to those of the control group. The intestinal fat ratio was reduced by the addition of 0.2 or 0.4 g/kg of quercetin (p < .05), and serum activities of alkaline phosphatase and superoxide dismutase were increased by the addition of 0.4 and 0.6 g/kg of quercetin (p < .05). The inclusion of 0.2–0.6 g/kg of quercetin increased the contents of delicious amino acids and decreased the cooking loss of flesh (p < .05). Flesh collagen content was increased by the addition of 0.4–0.8 g/kg of quercetin (p < .05). In conclusion, dietary quercetin could improve the growth and enhance the antioxidation and flesh quality of grass carp, with the recommended supplemental level of quercetin was 0.37 g/kg.  相似文献   
2.
【目的】 试验旨在探讨槲皮素在防治仔猪感染猪流行性腹泻病毒(PEDV)中的作用。【方法】 选取18头体重相近、健康的7日龄仔猪(杜×长×大),随机分为3组(对照组、PEDV组和PEDV+槲皮素组),每组6个重复,每个重复1头猪,试验期共11 d。经过3 d适应期后,于试验第4~10天给PEDV+槲皮素组仔猪口腔灌服10 mg/kg BW的槲皮素,其他组仔猪口腔灌服等体积的人工乳,于试验第8天给PEDV组与PEDV+槲皮素组仔猪口腔灌服1×104.5TCID50的PEDV,对照组灌服等体积的PBS溶液。试验第11天早上空腹称重,全部仔猪灌服D-木糖(0.1 g/kg BW),1 h后经前腔静脉采血,检测血液生化指标、血浆二胺氧化酶(DAO)活性和D-木糖含量;将所有仔猪屠宰取空肠黏膜,检测肠道屏障相关基因,包括肠绒毛蛋白(villin),紧密连接蛋白-1(claudin-1),闭合蛋白(occludin)和肠型脂肪酸结合蛋白(iFABP)的相对表达量。【结果】 与对照组相比,PEDV组仔猪平均日增重显著下降(P<0.05),粪便评分显著升高(P<0.05);血液中高密度脂蛋白含量显著降低(P<0.05),肌酐和尿素氮的含量显著提高(P<0.05);血浆中D-木糖含量显著降低(P<0.05);空肠claudin-1、iFABP基因的相对表达量显著下调(P<0.05)。与PEDV组相比,PEDV+槲皮素组仔猪平均日增重和血浆D-木糖含量显著升高(P<0.05);血液中肌酐和尿素氮的含量显著降低(P<0.05);空肠claudin-1、villiniFABP基因的相对表达量显著上调(P<0.05)。【结论】 10 mg/kg BW槲皮素可在一定程度上缓解PEDV感染导致的仔猪生长抑制和肾功能损伤,增强肠道吸收与屏障功能。  相似文献   
3.
【目的】 通过研究槲皮素对猪流行性腹泻病毒(PEDV)感染仔猪肠道形态、肠道抗氧化功能及空肠脂质代谢相关基因相对表达量的影响,旨在探讨槲皮素对PEDV感染仔猪肠道的保护作用。【方法】 选取18头健康的7日龄断奶仔猪,随机分为3组:对照组、PEDV组和槲皮素+PEDV组,每组6个重复,每个重复1头猪。试验期8 d,于试验第0~7天,对槲皮素+PEDV组仔猪每天口腔灌服10 mg/kg BW的槲皮素,其余组灌服等体积的人工奶。于试验第5天晚上给PEDV组和槲皮素+PEDV组仔猪口腔灌服104.5TCID50的PEDV,对照组仔猪灌服相同体积的PBS溶液。于试验第8天早上屠宰,取仔猪十二指肠、空肠、回肠及结肠组织样品进行检测。【结果】 与对照组相比,PEDV组仔猪空肠和回肠的绒毛高度以及绒毛高度与隐窝深度比值极显著降低(P<0.01),空肠、回肠和结肠中谷胱甘肽过氧化物酶(GSH-Px)和总超氧化物歧化酶(T-SOD)的活力显著降低(P<0.05),十二指肠、空肠、回肠和结肠中过氧化氢酶(CAT)的活力显著降低(P<0.05),回肠和结肠中丙二醛(MDA)的含量显著升高(P<0.05),空肠中载脂蛋白A1(APOA1)、载脂蛋白B (APOB)、载脂蛋白C2(APOC2)、脂肪酸结合蛋白2(FABP2)、酰基辅酶A合成酶长链家族成员3(ACSL-3)和脂肪酸合酶(FASN)基因的相对表达量极显著下调(P<0.01)。与PEDV组相比,槲皮素+PEDV组仔猪空肠和回肠的绒毛高度以及绒毛高度与隐窝深度比值极显著提高(P<0.01),空肠、回肠和结肠中GSH-Px和T-SOD的活力显著提高(P<0.05),十二指肠、空肠和结肠中CAT的活力显著提高(P<0.05),回肠和结肠中MDA的含量显著降低(P<0.05),空肠中APOB、FABP2和FASN基因的相对表达量极显著上调(P<0.01)。【结论】 添加槲皮素可有效缓解PEDV感染导致的仔猪肠道损伤,提高仔猪肠道抗氧化能力以及空肠脂质代谢的能力。  相似文献   
4.
槐花米抗氧化成分的提取及其活性研究   总被引:7,自引:1,他引:7  
用75%乙醇提取了槐花米中具有抗氧化活性的粗提物,然后通过碱提酸沉法从该粗提物中提取了芦丁,并制备了芦丁的水解产物槲皮素。采用磷钼酸盐法测定了不同质量浓度的粗提物、芦丁和槲皮素的抗氧化活性,并与BHT、VC的抗氧化活性进行了比较。结果表明,抗氧化性强弱顺序为:VC>槲皮素>芦丁>粗提物>BHT。  相似文献   
5.
TLC—UV法测定银杏叶中槲皮素的含量   总被引:1,自引:0,他引:1  
建立了银杏叶黄酮类成分槲皮素的薄支析测定方法,分析条件:硅胶GF254薄层,展开剂为苯-醋酸乙酯-丙酮-甲酸(10:8:2:1,体积比),无水乙醇作解吸溶剂,吸光度检测波长360nm。结果表明:该法精确、重现性好和线性范围宽。  相似文献   
6.
Legumes contain a range of non‐nutritional phytochemicals that may have health‐promoting effects in humans. In this study, we determined the concentrations of four phytoestrogens (coumestrol, apigenin, luteolin and quercetin) in field‐grown alfalfa (Medicago sativa L.). Differences between plants of different stages of maturity, between plant parts, and different canopy segments were assessed. The concentration of individual phytoestrogen in whole herbage varied between 15 and 225 μg g?1 dry matter (DM) and was strongly affected by stage of maturity. Coumestrol and apigenin concentrations were highest at early vegetative stages, luteolin and quercetin at early vegetative and late flowering stages. All phytoestrogens were found in lowest concentrations at the early flowering stage (average 68 μg g?1 DM); stage at which alfalfa is usually harvested when used as a forage source for animals. At vegetative stages, apigenin was the predominant phytoestrogen in herbage followed by coumestrol, the reverse being observed upon initiation of flowering; luteolin and quercetin were found at all stages in similarly lower concentrations. Concentrations of luteolin, quercetin and apigenin were 225, 410 and 690 % greater, respectively, in flowers than in leaves or stems; coumestrol concentration was similar between plant parts. In flowers and stems the predominant phytoestrogens were apigenin and quercetin, followed by coumestrol and luteolin. Similar concentrations (average 26 μg g?1 DM) of each of the four phytoestrogens were found in leaves. Concentrations through the herbage canopy varied and were greatest at >60 cm from the soil surface for apigenin and coumestrol, but greatest at >60 and 0–20 cm for quercetin and at 0–20 cm for luteolin. The results suggest that if alfalfa is to be used as a source of phytoestrogens and is harvested for the production of herbal supplements or nutraceuticals, management will need to be adapted.  相似文献   
7.
An experiment was conducted to evaluate the effects of in ovo injection of chrysin, quercetin and ascorbic acid on hatchability, somatic attributes, hepatic antioxidant status and early post‐hatch growth performance of broiler chicks. Four hundred and eighty embryonated broiler breeder eggs containing live 18‐day‐old embryos were divided into six groups of 80 eggs each. One group remained intact and served as a control group (i), whereas the other five groups were injected with the prepared injection solutions as follows: (ii) 0.05 ml distilled water; (iii) 0.05 ml distilled water containing 6 mg ascorbic acid; (iv) 0.05 ml dimethyl sulfoxide (DMSO); (v) 0.05 ml DMSO containing 4.5 mg quercetin; and (vi) 0.05 ml DMSO containing 4.5 mg chrysin. The hatchability rate, hatching weight, residual yolk sac weight, yolk sac‐free body weight, liver weight, hepatic glutathione peroxidase and total superoxide dismutase activities, as well as malondialdehyde concentrations, were not affected by the injected solutions. There were no differences between chicks hatched from the control and in ovo injected eggs in weight gain, feed intake and feed conversion ratio from 0 to 11 days of age. However, the specific contrast performed between the in ovo injected groups and intact eggs revealed that in ovo injection significantly increased hatchability rate (p = .0493). This finding also implies that our injection procedure was harmless. In conclusion, the intra‐egg injection of chrysin, quercetin or ascorbic acid at the injection rates used in this study did not have a significant effect on hatchability, somatic characteristics, early growth performance and hepatic antioxidant status of broiler chicks. However, the overall hatchability was higher in the in ovo injected eggs as compared to non‐injected ones. These findings also confirmed the harmlessness of the procedure developed for in ovo injection in this study.  相似文献   
8.
Current study was carried out to examine the protective effects of quercetin against toxicity induced by hydrogen peroxide in rooster semen in vitro. Semen samples were collected from ten roosters (Ross 308 broiler breeder males, 32 weeks old) twice a week by abdominal massage method. Samples with ≥70% progressive motility were selected, pooled, diluted and used for the study. Experimental groups consisted of negative control, control that received solvent of quercetin, H2O2 (40 μM) and combination groups which incubated with constant dose of H2O2 (40 μM) plus various levels of quercetin (20, 40 and 80 μM). Measurement of total hydroperoxide (HPO), malondialdehyde (MDA), nitric oxide (NO), total antioxidant capacity (TAC) and superoxide dismutase activity as well as routine sperm tests were done at 0, 24 and 48 hr of storage at 4°C. Results revealed that exposure to hydrogen peroxide significantly increased HPO (138.43 ± 7.32 vs. 66.08 ± 3.97 μmol/g protein), MDA (7.21 ± 0.08 vs. 5.71 ± 2.16 μmol/g protein) and NO (0.367 ± 0.013 vs. 0.215 ± 0.011 μmol/g protein) levels and decreased sperm progressive motility (27.28 ± 1.21 vs. 47.49 ± 1.29%), and amounts of TAC (11.49 ± 0.39 vs. 15.70 ± 0.79 mmol/g protein) compared to control at 24 hr (p < 0.05). Changes at mentioned variables were repeated at 48 hr of storage. Also, co‐administration of quercetin (especially at 40 and 80 μM) with hydrogen peroxide restored the toxic effects of hydrogen peroxide on rooster semen parameters such as primary and secondary lipid peroxidative indicators and other evaluated variables. The study concluded that rooster semen enrichment with quercetin would protect lipid peroxidative and nitrosative hydrogen peroxide‐mediated damage during cold liquid storage of rooster semen.  相似文献   
9.
The objective of this study was to characterize the flavonoid compounds found in the different grain parts of common and tartary buckwheat, and to determine the contribution of these flavonoids to the antioxidant properties of buckwheat. Eight flavonoid compounds were quantified and their antioxidant activity determined by FRAP, DPPH, and ABTS assays. Of the flavonoid compounds identified rutin was the most abundant, particularly in tartary buckwheat, in which it comprised approximately 90% of total flavonoid content. Flavan-3-ols were detected in common but not tartary buckwheat, and quercetin was detected only in tartary buckwheat. Flavonoid content—in particular, levels of rutin, orientin, and/or epicatechin gallate—was found to influence the total antioxidant activity of buckwheat. Results from this study indicate that antioxidant activity is not only closely associated with flavonoid content, but that different flavonoids contribute differently to the total antioxidant activity of common and tartary buckwheat.  相似文献   
10.
为完善甜地丁质量标准,采用薄层色谱法对甜地丁中槲皮素的鉴别进行了研究,并用高效液相色谱法测定其含量。薄层色谱以甲苯-乙酸乙酯-甲酸(7:5:0.5)为展开剂,高效液相法色谱柱为C18(4.6mm×250mm,5μm),流动相为甲醇-0.3%磷酸溶液(50:50),检测波长为360nm,流速1mL/min,柱温25℃,进样量10μL。结果表明薄层色谱法能对槲皮素实现有效分离,高效液相色谱法槲皮素进样浓度在5。100μg/mL范围内与峰面积呈良好的线性关系(r=O.9997);样品平均回收率为96.1%(n=6),RSD为0.7%。本方法为进一步控制甜地丁的质量提供了依据。  相似文献   
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