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151.
Jiang SZ Yang ZB Yang WR Wang SJ Wang Y Broomhead J Johnston SL Chi F 《Journal of animal physiology and animal nutrition》2012,96(6):1147-1156
The objectives of this study were to investigate the toxicity of zearalenone (ZEA) on hepatonephric organs, serum metabolites and oxidative stress of piglets and to evaluate the efficacy of Calibrin‐Z (CAZ) in preventing ZEA‐induced adverse effects. The experiment was conducted for 22 days using 36 piglets weaned at 21 days of age (Landrace × Yorkshire × Duroc, 18 females and 18 males; 8.84 ± 0.21 kg average body weight). Piglets of each gender were randomly allocated to the following six dietary treatments: (i) Control (basal diet only); (ii) Control + 1 g/kg CAZ; (iii) Control + 1 mg/kg ZEA; (iv) Control + 1 mg/kg ZEA + 1 g/kg CAZ; (v) Control + 1 mg/kg ZEA + 2 g/kg CAZ; (vi) Control + 1 mg/kg ZEA + 4 g/kg CAZ. Piglets were housed and fed individually for the entire experimental period. Blood samples were taken, and piglets were killed at the end of the experiment to obtain organs for physiological assessment. Results showed that piglets fed the ZEA‐contaminated diet had increased (p < 0.05) activities of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma‐glutamyltransferase (GGT), creatine kinase and cholinesterase, concentrations of urea, and creatinine in serum, and malondialdehyde (MDA) in serum and liver. Pigs fed the ZEA‐only diet also showed reductions in serum (p < 0.05) globulin, triglycerides and high‐density lipoproteins (HDL), and reductions in total superoxide dismutase (TSOD) and glutathione peroxidase (GSHPx) activity in both serum and liver. Supplementation of CAZ at the dosages of 1–4 g/kg to the diet containing 1.05 mg/kg ZEA linearly increased (p < 0.05) concentrations of triglycerides and HDL in serum, activity of TSOD and GSHPx in serum and liver, but linearly reduced (p < 0.05) all tested serum enzymes and lowered (p < 0.05) the elevated concentrations of urea, and creatinine in serum, and MDA in serum and liver caused by dietary ZEA. Piglets fed the ZEA‐contaminated diet showed increased (p < 0.05) relative weight of liver and kidney compared with the control, whereas only numerical improvement on relative weight of liver and kidney was observed with simultaneous addition of CAZ at 4 g/kg diet and ZEA. However, feeding the diet with CAZ alone at 1 g/kg had no impact on any of the measured parameters when compared to the control. It is suggested that feeding ZEA at 1.05 mg/kg exerted a deleterious effect on piglets, which was totally or partly ameliorated by dietary supplementation of CAZ at concentrations between 1 and 4 g/kg diet. 相似文献
152.
棉籽粕源发酵蛋白质饲料的代谢产物研究 总被引:2,自引:0,他引:2
本试验旨在通过液相色谱串联质谱(LC-MS)代谢组学分析平台对不同微生物棉籽粕源发酵蛋白质饲料代谢产物进行研究.采用LC-MS法对对照组、假丝酵母组、酿酒酵母组、复合组的发酵代谢产物进行分析,结合偏最小二乘法-判别分析(PLS-DA)方法对数据进行模式识别和小分子差异代谢产物寻找.结果表明:各试验组代谢产物相对含量与对照组相比差异显著(P<0.05),且在PLS-DA分析中得到了很好的分离,主要表现在甘露醇、琥珀酸等糖类代谢产物;磷酸胆碱、L-肉碱、甘油磷酸、磷脂酰乙醇胺(PE)和磷脂酰胆碱(PC)等脂类代谢产物;二肽、三肽、甜菜醛、同型半胱氨酸等蛋白质与氨基酸的代谢产物;以及烟酸、阿魏酸、尿嘧啶、乙醇醛等其他途径代谢产物.除与脂类代谢有关的甘油磷酸、PE、PC相对含量显著降低之外(P<0.05),其他试验组小分子代谢产物相对含量均比对照组显著增加(P<0.05).由此可见,不同菌种发酵饲料中含有大量糖类、脂类、蛋白质等代谢途径产生的小分子代谢产物,含量因发酵菌种的不同而不同. 相似文献
153.
采用HPLC-DAD-MSn法对兔肌注恩诺沙星给药后血浆中恩诺沙星和代谢产物的紫外光谱和质谱裂解行为进行分析,获得各化合物的光谱和多级质谱信息。比较给药前后兔血浆的DAD检测色谱图,发现6个可能的代谢产物M1……M6。根据化合物结构和质谱裂解途径及标准品的色谱保留时间,确定M3为环丙沙星,并推测M5可能为加氧恩诺沙星;M4获得一级质谱数据和紫外光谱数据;M1、M2和M6仅得到紫外光谱数据。推测恩诺沙星在兔体内的主要代谢反应是脱乙基反应和氧化反应。 相似文献
154.
桃3种砧木次生木质部导管分子性状比较 总被引:1,自引:0,他引:1
为桃树抗寒砧木的选择提供参考依据,采用组织离析、显微照相与生物计量统计法,检测并比较了山桃(Prunus davidiana)(SP)、毛桃(P.persica)(MP)和珲春桃(P.persica cv.Hun-chun-tao)(HP)3种桃砧木根与茎导管分子形态和大小。结果表明,3种桃砧木导管分子性状相比较,根与茎导管分子侧壁次生增厚和木质化的方式、纹孔式、穿孔板类型以及其根一端具尾的导管分子比例基本相似,其茎导管分子均具有螺旋加厚现象,但是,两端具尾、一端具尾、两端无尾、两端倾斜、一端倾斜和两端水平的导管分子比例以及导管分子的长度与直径、根与茎导管分子长度与直径的比率均存在差异。 相似文献
155.
156.
157.
Phuong-Y. Mai Graldine Le Goff Erwan Poupon Philippe Lopes Xavier Moppert Bernard Costa Mehdi A. Beniddir Jamal Ouazzani 《Marine drugs》2021,19(7)
Solid-phase extraction embedded dialysis (SPEED technology) is an innovative procedure developed to physically separate in-situ, during the cultivation, the mycelium of filament forming microorganisms, such as actinomycetes and fungi, and the XAD-16 resin used to trap the secreted specialized metabolites. SPEED consists of an external nylon cloth and an internal dialysis tube containing the XAD resin. The dialysis barrier selects the molecular weight of the trapped compounds, and prevents the aggregation of biomass or macromolecules on the XAD beads. The external nylon promotes the formation of a microbial biofilm, making SPEED a biofilm supported cultivation process. SPEED technology was applied to the marine Streptomyces albidoflavus 19-S21, isolated from a core of a submerged Kopara sampled at 20 m from the border of a saltwater pond. The chemical space of this strain was investigated effectively using a dereplication strategy based on molecular networking and in-depth chemical analysis. The results highlight the impact of culture support on the molecular profile of Streptomyces albidoflavus 19-S21 secondary metabolites. 相似文献
158.
Birthe M. Damgaard Christian F. Børsting Klaus L. Ingvartsen Rikke Fink 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(3):127-135
The effects of carbohydrate-free diets on body weight changes, feed consumption, and plasma concentrations of nutrients, metabolites, and hormones in lactating mink and on growth performance in kits were investigated in a total of 108 litters during the lactation period of seven weeks. The litters were distributed in three experimental groups fed different ratios of metabolisable energy (ME) derived from protein and fat (61:38; 47:52; 33:66). The females and kits were weighed at parturition and 2, 3, 4, and 7 weeks after parturition. Blood samples were collected from females in the second, fourth, and sixth week of the lactation period. Carbohydrate-free diets fed to lactating mink can in principle support normal performance, health of the females, and growth performance of the kits. However, mink need a sufficient supply of available gluconeogenic precursors in the form of amino acids. In the present experiment, the diet with 33% of ME from protein contained insufficient amounts of gluconeogenic precursors for lactating mink, and three weeks post partum this group was excluded from the experiment. The differences in dietary protein level (61% and 47% of ME) and fat level (38% and 52% of ME) influenced the plasma concentrations of free fatty acids (FFA) and urea, but had minimal influence on plasma concentrations of other nutrients, metabolites, and hormones. 相似文献
159.
Chun-Yan An Xiao-Ming Li Chun-Shun Li Ming-Hui Wang Gang-Ming Xu Bin-Gui Wang 《Marine drugs》2013,11(7):2682-2694
Four new quinazolinone alkaloids, namely, aniquinazolines A–D (1–4), were isolated and identified from the culture of Aspergillus nidulans MA-143, an endophytic fungus obtained from the leaves of marine mangrove plant Rhizophora stylosa. The structures of the new compounds were elucidated by spectroscopic analysis, and their absolute configurations were determined on the basis of chiral HPLC analysis of the acidic hydrolysates. The structure for 1 was confirmed by single-crystal X-ray diffraction analysis. All these compounds were examined for antibacterial and cytotoxic activity as well as brine shrimp (Artemia salina) lethality. 相似文献
160.