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151.
褪黑素在植物生长、发育、生物与非生物胁迫中发挥重要作用.色氨酸脱羧酶(tryptophan decarboxylase,TDC)是褪黑素生物合成中第一个重要的酶.本研究克隆川桑TDC基因,并将其转入烟草中过表达,探讨MnTDC在盐胁迫下的作用机制.结果 表明,成功构建过表达载体pLGNL-MnTDC,并经过农杆菌介导的愈伤组织转化获得3个独立转基因系.GUS染色、基因组PCR鉴定证明MnTDC成功转化到烟草株系中.qRT-PCR结果表明MnTDC在3个转基因烟草株系中的转录水平显著高于野生型(WT).UPLC-MS/MS结果表明转基因株系显著提高了褪黑素的生物合成量.盐胁迫下,Mn TDC过表达烟草与野生株系烟草相比,耐盐性显著增强.转基因烟草株系中的过氧化氢酶(CAT)、超氧化物歧化酶(SOD)及过氧化物酶(POD)活性均显著高于野生株系烟草,脯氨酸(Pro)等调节渗透压物质的含量和ERD10C等调节渗透压的基因表达量显著高于野生株系烟草,转基因株系中丙二醛(MDA)含量比野生株系烟草低.研究结果表明,MnTDC通过调节烟草细胞中褪黑素的含量进而影响了烟草植株整体的耐盐性.本研究初步揭示了MnTDC基因的抗逆功能,为桑树耐盐分子育种提供了重要候选基因和理论参考. 相似文献
152.
Runqi Fu Chan Liang Daiwen Chen Hui Yan Gang Tian Ping Zheng Jun He Jie Yu Xiangbing Mao Zhiqing Huang Yuheng Luo Junqiu Luo Bing Yu 《Journal of animal physiology and animal nutrition》2021,105(5):898-907
The present study investigated the effects of Bacillus coagulans and yeast hydrolysate supplementation on growth performance, immune response and intestinal barrier function of weaned piglets. Twenty-four weaned piglets with an average body weight (BW) of 6.89 ± 0.15 kg were divided into four diets for 28 days. The treatments were basal diet (control), basal diet supplemented with antibiotic (20 mg/kg colistin sulphate and 40 mg/kg bacitracin zinc, AT), probiotics (400 mg/kg Bacillus coagulans ≥5 × 109 CFU/g, BC) or yeast hydrolysate (5000 mg/kg yeast hydrolysate, YH). Average daily gain (ADG) and average daily feed intake (ADFI) were improved by AT and YH diets (p < 0.05), while BC diet only increased ADG (p < 0.05). The complement 3 (C3), lysozyme (LZM) and tumour necrosis factor-α (TNF-α) concentrations in serum were increased in BC diet (p < 0.05). Feeding AT and YH caused the increase of jejunal villus height (p < 0.05), and a higher ratio of villus height/crypt depth was observed in AT, BC and YH groups (p < 0.05). The mRNA expression of zonula occludens-1 (ZO-1) in jejunal mucosa was up-regulated by AT, BC and YH diets (p < 0.05). Dietary AT, BC or YH inclusion decreased the interleukin-1β (IL-1β) concentration and TNF-α mRNA expression (p < 0.05), and YH supplementation even down-regulated toll-like receptor 4 (TLR4) and CD14 expressions (p < 0.05). In summary, the dietary administration of BC or YH both improves growth performance through promoting the intestinal barrier function, indicating both of them can serve as potential alternatives to antibiotics growth promoters for the piglet production. 相似文献
153.
为了解保健砂中主要矿物质元素的含量情况,试验采集了6省共11个地区的鸽保健砂产品,首先比较了用湿法消化、干法消化和酸溶解法对钙磷待测样品进行前处理的效果,分别按照GB/T 6436-2018和GB/T 6437-2018测定方法测定了样品中的Ca、P含量,接着采用GB/T 13885-2017方法测定了样品中Fe、Cu、Zn、Mn的含量。结果表明:Ca的测定3号样品干法较湿法消化结果高3.16%(P < 0.05),5号样品干法、酸溶解法较湿法消化结果分别低0.87%、2.16%(P < 0.05),三种方法中酸溶解法最适合对保健砂进行前处理|多数省(市)的保健砂样品均有较高含量的Ca,最高达到29.4%|P含量普遍严重偏低,8个样品的P含量都在0.05%以下,比其余样品的P含量低数十倍|钙磷比多数都在100以上,最高钙磷比达到792,保健砂中钙磷比例严重失衡|样品中Fe、Cu、Zn、Mn的含量分别为3387 ~ 22185、3.8 ~ 112.5、7.46 ~ 865.5 mg/kg和58.8 ~ 1401 mg/kg。由此可见,保健砂中各矿物质元素含量差异均极大,迄今没有统一的标准,质量问题不容忽视。
[关键词] 保健砂|矿物质元素|前处理|钙|磷 相似文献
154.
Zhu Zeng Yalin Zhang Jun He Jie Yu Xiangbing Mao Ping Zheng Yuheng Luo Junqiu Luo Zhiqing Huang Bing Yu Daiwen Chen 《动物营养(英文)》2021,7(2):393
There are appreciable does of raffinose in soybean, but the impacts of raffinose on pigs are poorly investigated. We used 2 experiments to investigate the influence of soybean raffinose on growth performance, digestibility, humoral immunity and intestinal morphology of growing pigs. In Exp. 1, a total of 30 crossbred (Duroc × Landrace × Yorkshire) barrows (21.93 ± 0.43 kg) were randomly divided into 3 groups, and were fed with the control diet, the control diets supplemented with 0.2% and 0.5% raffinose, respectively, for 21 d. Results showed that the addition of 0.2% or 0.5% raffinose reduced (P < 0.05) average daily feed intake (ADFI), average daily gain (ADG) and nutrient digestibility, and dietary 0.5% raffinose increased the ratio of feed to gain (P < 0.05). For serum indexes, dietary 0.5% raffinose decreased growth hormone and increased glucagon-like peptide-2, immunoglobulin G, tumor necrosis factor-α (TNF-α) and interleukin-6 concentration (P < 0.05). In Exp. 2, a total of 24 crossbred barrows (38.41 ± 0.45 kg) were randomly divided into 3 groups, and were fed with the control diet (ad libitum), the raffinose diet (0.5% raffinose, ad libitum), and the control diet in the same amount as the raffinose group (feed-pair group) for 14 d, respectively. Compared with the control diet, dietary 0.5% raffinose decreased ADFI (P < 0.05). Intriguingly, the raffinose group had lower ADG than the feed-pair group, lower nutrient digestibility, lower amylase activity in duodenum, lower amylase, lipase and trypsin activities in jejunum and higher TNF-α concentration in serum compared with the other 2 groups, and a higher ratio of villus height to crypt depth compared with the control group (P < 0.05). These results showed that soybean raffinose could reduce feed voluntary intake and body gain while improving intestinal morphology without a significant negative influence on immunity. Taken together, dietary raffinose could decrease growth performance by reducing both feed intake and nutrient digestibility while inducing humoral immune response of growing pigs. 相似文献
155.
连续流粮食干燥过程是一个非线性大滞后多变量的过程,要精确控制粮食出口的终水分比较困难。本文设计一种新的连续流粮食干燥过程的控制方法,对连续流粮食干燥过程中的多个影响因素进行研究,分析粮食干燥自控系统在设计时所必须选择的可测干扰、数字变量、控制变量和被控变量等,并且提出基于自适应逆控制技术的连续流粮食干燥系统的离散化模型,主要针对工业控制对象中存在的时变和时滞问题,推导出该连续流粮食干燥控制系统的预测模型。通过实验对实际系统进行验证,结果证明本系统具有较好的鲁棒性和稳定性。 相似文献
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