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1.
果寡糖对猪粪便细菌群作用下L-色氨酸代谢的影响 总被引:3,自引:0,他引:3
本试验研究了果寡糖对猪粪便细菌群作用下L -色氨酸代谢的影响。将 10 % (W/V)粪水厌氧分装于无菌瓶中 ,分成 4组 :1组 (对照 )添加 2 5 0 μmol/LL -色氨酸 ;2~ 4组 :分别在对照组的基础上添加 0 .5 % ,1.0 %和 1.5 %果寡糖。 38℃、厌氧培养。在培养期的不同时间点 (0 ,2 ,4 ,6 ,8,12 ,18,2 4h)分别从各瓶中取 1mL培养液 ,分析各培养液中吲哚类物质含量。培养 2 4h后 ,分析各培养液中细菌学指标和pH。结果表明 :含L -色氨酸的体外培养液中添加 0 .5 % ,1.0 %和 1.5 %果寡糖 ,培养 2 4h后 ,使粪臭素浓度、吲哚 - 3-乙酸峰值和pH值均显著降低。添加1.0 %和 1.5 %果寡糖显著降低色氨酸降解率和粪臭素相对产率 ,显著提高吲哚相对产率 ,显著降低梭菌和大肠杆菌数 ,显著增加双歧杆菌和总厌氧菌数。 相似文献
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《Journal of Veterinary Behavior: Clinical Applications and Research》2014,9(5):248-253
Horse trekking is a noncompetitive physical activity conducted as a recreation and leisure experience, but so far potential effects on physiological changes in horses have not been investigated. The aim of the present research was to study whether trekking would affect plasma serotonin (5-hydroxytryptamine [5-HT]) concentrations in platelet poor plasma samples, together with its precursor tryptophan, and other hematological and functional variables. The study was carried out on 28 clinically healthy horses, habitually used for trekking, of which 18 participated in a 2-day trekking event, and 10 were used as the control group. The results obtained showed a significant effect of exercise on the serotonin, red blood cell, white blood cell, platelet, hematocrit, hemoglobin, heart rate, respiratory rate, and rectal temperature changes. These effects are probably related to a combination of submaximal exercise and some degree of dehydration. Prolonged and aerobic exercise, like that involved in trekking, could affect both the release of 5-HT from the stores in the blood stream as well as hematological and functional adaptations in response to physical effort. Moreover, results confirm a physiological influence of 5-HT in the regulation of the vascular system, induced by exercise. The present findings imply that assessment of plasma 5-HT as well as hematological and functional variables may be proposed as an additional tool to evaluate the physiological adjustment in response to physical activity in trained horses that may influence their performance. 相似文献
4.
L-色氨酸对喜树愈伤组织中喜树碱合成的影响 总被引:1,自引:0,他引:1
喜树碱是一种从天然植物喜树中分离的抗癌活性物质,通过细胞培养合成喜树碱是喜树碱生产的一条重要途径。本试验利用喜树的顶芽、叶片、茎段为外植体,在B5培养基上(附加1.0 mg/l的NAA,0.5 mg/l的2,4-D和0.5 mg/l的KT)诱导喜树愈伤组织。同时考察L-色氨酸对喜树愈伤细胞培养中喜树碱积累的影响,结果表明,在B5培养基中添加0.001-0.002 mg/ml的L-色氨酸,对喜树愈伤细胞的生长没有明显影响,但是对喜树愈伤细胞合成喜树碱的促进作用明显,喜树碱含量比未添加L-色氨酸培养的愈伤增加了3倍。 相似文献
5.
A feed trial was conducted with a total of 1 134 Beijing ducklings to study the optimum level of dietary lysine (Lys) (0.95,1.10, 1.25%), methionine (Met) (0.26, 0.46, 0.66%) and tryptophan (Trp) (0.20, 0.30, 0.40%) for those ducklings during aphase of 0-2 weeks. Ducklings were randomly allotted to 27 groups according to a 3 × 3 × 3 factorial arrangement and fed a basal corn-soybean-peanut meal diet containing 20.26% CP, 12.45 MJ kg-1 ME. The results from this study indicate that Lys affected body weight (P<0.01), feed intake (0-14 d) (P<0.01), but had no effect on feed/gain (0-14 d) (P>0.05), uric acid concentration (P > 0.05). Methionine influenced body weight (P < 0.01), feed/gain (P < 0.05), and feed intake (P < 0.01). Tryphtophan had no effect on indices measured. The requirement of the Lys and Met for Beijing ducklings of 0-2 weeks of age were 1.10 and 0.46%. The requirement of Trp for Beijing ducklings of 0-2 weeks of age was not more than 0.20%. 相似文献
6.
LIU Hua-zhen TANG Wen-hua PENG Ke-mei CHEN Wen-qin LUO Guan-zhong WANG Yan WEI Lan 《中国农业科学(英文版)》2006,5(6):473-477
Healthy Cherry Valley ducks were used in the present study. Different doses of tryptophan were injected intraperitoneally to them after being fasted 4 h (8:00 a.m.-12:00 a.m.). One hour later, they were deeply anaesthetized and perfused. The cerebellum was removed to make serial paraffin longitudinal sections. The streptavidin-biotin-peroxidase complex (SABC) method was used to study the distribution of serotonin-like neurons in the cerebellum. All films were analysed by using a computer-assisted image analysis system. Serotonin-like neurons are only localized in cerebellar Purkinje cell layer. The optical density averages of serotonin-like neurons in 200 and 100 mg kg^-1 group are significantly higher than that of 0 mg kg^-1 group (P〈0.01). These results show that serotonin-like neurons are distributed in Purkinje cell layer and that excessive tryptophan can affect the content of serotonin in cerebellum. 相似文献
7.
通过试验研究色氨酸对12~17周龄金定蛋鸭的免疫指标和性成熟指标的影响,最终确定后备蛋鸭色氨酸的需要量。选择12周龄健康的金定蛋鸭180只,随机分成5组,每组6个重复,每个重复6只。处理Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ组饲喂色氨酸水平分别为0.199%、0.22%0、.24%、0.26%、0.30%。采用二次曲线方程确定后备蛋鸭的色氨酸适宜水平。结果表明:①0.252%~0.269%的色氨酸能显著提高试鸭血清白细胞介素(IL-2)和免疫球蛋白G(IgG)含量(P<0.05),显著降低血清皮质醇(Cort)和免疫球蛋白M(IgM)的含量(P<0.05)。0.252%~0.255%的色氨酸能显著提高试鸭的胸腺指数、法氏囊指数和脾指数(P<0.05)。②0.242%~0.260%的色氨酸对试鸭促卵泡激素(FSH)和雌二醇(E2)分泌影响不显著(P>0.05),对血清中促黄体生成素(LH)和孕酮(P4)影响显著(P<0.05)。0.247%~0.250%的色氨酸能促进试鸭生殖器官的发育,但不显著(P>0.05)。试验结果提示:以免疫指标及性成熟为评价指标1,2~17周龄金定蛋鸭的适宜色氨酸水平为0.242%~0.269%。 相似文献
8.
用氨基酸自动分析仪分析色氨酸方法研究 总被引:1,自引:0,他引:1
比较研究多种水解剂及水解条件对蛋白质色氨酸(TRP)的分析效果,结果证明4mol/LLiOH110℃水解20h效果最好,其次是5mol/LNaOH+5%SnCl2110℃,20h。进一步试验发现6mol/LLiOH120℃水解6h可以缩短水解时间,其样品回收率与4mol/LLiOH条件的相当或略高。实验证明样品水解必须充入高纯氮气。试验了排除氨干扰的方法,认为直接除氨法可有效消除氨对测定的影响。对中和条件、样品水解液的保存进行了试验。经改进上机分析程序,可节省2/3的茚三酮试剂。 相似文献
9.
Phosphorus (P) and zinc (Zn) are important determinants of plant productivity, particularly in the tropical grasslands of Brazil. Nutrient deficiency is one of the most important factors limiting plant productivity, decreasing photosynthesis efficiency and plant development. The present study investigates in Brachiaria brizantha (Hochst. ex A. Rich.) Stapf. cv. ‘Marandu’: 1) the gas exchange measurements; 2) the total leaf area development; and 3) the dry matter production due to P and Zn nutrition. Plants of B. brizantha cv. ‘Marandu’ were grown in nutrient solution under five rates of P (0.1, 0.6, 1.1, 1.6, and 2.1 mmol L?1) and five rates of Zn (0.00, 0.75, 1.5, 2.25, and 3.00 μmol L?1), in a fractioned factorial. Plants were harvested two times. Phosphorus supply increased carbon dioxide (CO2) assimilation and stomatal conductance, and decreased intercellular CO2. The interaction P rates x Zn rates were significant for the total leaf area variables and shoot dry matter in the second growth period. The nutrition of P and Zn interfered in the B. brizantha productivity by changing the grass photosynthesis and leaf area. 相似文献
10.
采用活性炭对L-色氨酸发酵液的脱色工艺进行研究。通过单因素试验考察了活性炭用量、脱色时间、温度、pH值对脱色率和吸附率的影响,并通过正交试验对脱色条件进行优化,得出最佳的脱色工艺:活性炭用量0.5%,pH2.0,室温,脱色时间20min。 相似文献