共查询到19条相似文献,搜索用时 237 毫秒
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人工合成大豆球蛋白A3酸性多肽基因cDNA序列,构建原核表达载体pET30a-A3,将重组质粒转化大肠杆菌(E.coli)BL21后用IPTG诱导表达,经His亲和层析纯化,获得纯度约91%融合A3蛋白。Western blotting显示,所获得的A3融合蛋白可与对豆粕过敏的仔猪血清发生免疫反应,表明所得融合蛋白具有免疫活性。利用Lasergene7.0中Protean软件对A3蛋白氨基酸序列进行B细胞抗原表位预测和分析,推测其中97~113、156~160、169~176、186~193、271~284和295~312氨基酸区段是A3酸性多肽的B细胞抗原表位,其中169~176区段的平均抗原指数最高,表位抗原性最强。本结果为进一步研究该蛋白致敏机理及单抗制备奠定了初步基础。 相似文献
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大豆发芽过程中抗原蛋白降解及营养特性变化 总被引:1,自引:0,他引:1
研究大豆发芽过程中抗原蛋白降解、抗原活性和营养成分的变化规律。结果表明,发芽期间,大豆子叶组织结构变得疏松;主要抗原蛋白β-伴球蛋白的α′-和α-亚基降解较快,而β-亚基降解缓慢。大豆11S球蛋白的酸性链降解快,而碱性肽链降解慢。ELISA分析表明,在发芽的前4 d中,β-伴球蛋白和11S球蛋白的抗原活性剩余率分别为58%和76%,延长发芽时间抗原活性降低较小。整个发芽期间,必需氨基酸和总氨基酸含量变化不大,但天冬氨酸含量显著增加,谷氨酸的含量明显降低。抗坏血酸含量在发芽第3 d时达到最大值,延长发芽时间,其含量降低。综上可知,在发芽4 d时大豆的食用安全性和营养价值较为理想。 相似文献
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筛选了降解豆粕的优良菌株黑曲霉X03.通过正交试验确定了其固态发酵的最佳水解条件.结果表明:在发酵温度31℃、粉碎后豆粕粒径为1.0 mm、小麦粉添加量10%、接种量为4%、自然pH条件下发酵48 h,发酵豆粕大豆肽转化率可达63.5%. 相似文献
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以脱脂豆粕为原料,通过植物乳杆菌液态发酵后制备大豆分离蛋白,测定所得大豆分离蛋白的溶解性、乳化性、乳化稳定性、凝胶强度、持水性和持油性等功能性质。豆粕经发酵后所提大豆分离蛋白的溶解性、乳化性、凝胶强度、持水性和持油性均显著提高(p<0.05),乳化稳定性显著降低(p<0.05),持水性及持油性变化不大。SDS-PAGE电泳显示,豆粕经发酵后所提大豆分离蛋白在29.044.3 ku出现新条带,是由于乳酸菌所产蛋白酶的降解作用,大豆分离蛋白中大分子量蛋白被降解成小分子量蛋白,其中发酵对7S组分影响较大,对11S组分影响较小。经实验表明乳酸菌发酵可以有效改善大豆分离蛋白的功能性质。 相似文献
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采用Nagano法从豆粕中分离β-伴大豆球蛋白并酶解制备水解肽,以单因素试验和正交试验确定酶解最佳条件,通过高效液相法分析β-伴大豆球蛋白水解肽的分子量分布,比较并检测了β-伴大豆球蛋白水解肽和大豆分离蛋白水解肽的体外抗氧化效果。结果显示:在20g/L的底物浓度下的最佳条件为酶和底物比10000U/g,温度55℃,pH7.5,水解时间4h,水解度为72.7%,明显高于酶解大豆分离蛋白51.4%的水解度,且水解时间更短。β-伴大豆球蛋白水解肽主要为130~1000u的短肽,占肽总量的86.3%,均一性极高。β-伴大豆球蛋白水解肽对O2-.和.OH均有清除作用,清除.OH的能力明显高于大豆分离蛋白水解肽,即β-伴大豆球蛋白的水解肽对大豆肽清除.OH的作用贡献更大。 相似文献
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近年来,随着我国一直倡导无抗饲料养殖与发展,生物饲料逐渐成为饲料行业主要技术突破口和研究对象,越来越多的企业及科研工作者投身于生物饲料的开发与应用。发酵豆粕是目前研究最多也最为深入的一种生物饲料。阐述了发酵豆粕营养价值、抗营养因子、制备工艺以及在动物养殖行业中的应用。在制备工艺上,从发酵菌株的选择和工艺参数控制两方面剖析固态发酵过程对发酵产品品质的影响,包括菌种、发酵温度、发酵时间、pH以及水分含量等参数指标;在动物养殖中,由于发酵豆粕富含小分子肽、游离氨基酸、乳酸、益生菌等多种营养成分,深受饲料企业及养殖户青睐。从畜牧、禽类以及水产三大板块阐述发酵豆粕在养殖中对动物生长的影响,探讨发酵豆粕在动物养殖中的重要性;同时对发酵豆粕未来发展趋势进行了分析和总结。 相似文献
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大豆脱皮工艺及其对大豆取油工艺效果的影响 总被引:2,自引:2,他引:2
大豆脱皮不仅是大豆浸出取油工艺中生产低温豆粕必要的前处理工序,也应在生产高温饲用豆粕的大豆浸出取油工艺中推广应用。其目的是,提高豆粕的蛋白质含量,增加浸出设备的处理量,降低湿粕的含溶量和残油量,减少生产过程的能量消耗,改善油品质量。 相似文献
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G A Broderick 《Journal of dairy science》1986,69(11):2948-2958
Nitrogen solubility and enzymatic and rumen in vitro degradabilities indicated protein from expeller soybean meal was more resistant to ruminal degradation than that from solvent soybean meal. This was confirmed in Trial 1 by reduced rumen ammonia and branched-chain volatile fatty acids, and by 64% more supplemental protein escaping the rumen when cows were fed expeller soybean meal. In Trial 2, rations supplemented with either solvent or expeller soybean meal, averaging 16.4% protein, were fed to 12 cows in a crossover study. Production averaged 35.3 kg/d but was not influenced by diet. A small but significant improvement in milk to feed ratio occurred with expeller soybean meal. In Trial 3, four sources of protein were fed to 20 cows in a 4 X 4 Latin square: 6.3% solvent, 4.1% expeller (plus .3% urea), 10.0% solvent, or 6.6% expeller soybean meal. Production of milk and milk components was similar on the diets containing 6.3 and 6.6% soybean meal, intermediate on 10.0% solvent, and least on the expeller-urea diet. Milk to feed was equal and greatest on diets containing 6.6% expeller and 10.0% solvent soybean meal, indicating comparable utilization of the expeller diet containing only 60% as much supplemental protein. 相似文献
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Five primiparous Holstein cows (483 kg BW) of low productivity were used in a 4 x 5 incomplete Latin square design to study the effects of feeding two levels of grain containing soybean meal and one level of grain containing fish meal on feed intake, milk production, digestibility, and rumen fermentation. Animals all were fed alfalfa silage for ad libitum intake. Collection of data was between wk 11 and 24 of lactation. The four treatments were an all silage diet (control), silage and medium concentrate fed at 1.8% BW containing soybean meal, and silage and low concentrate fed at 1.3% BW containing either soybean meal or fish meal. Treatments other than control were designed to give similar CP intake from the concentrate, which was based on high moisture corn and cob meal. Milk production and composition were similar among treatments except for fat percentage, which was significantly lower for low grain soybean meal. Intake of DM was higher on medium grain soybean meal compared with the other treatments. Average BW and change in BW (.11 kg/d) were not affected by treatments. Digestibility of DM was higher for cows fed grain (68 to 73%) than for those fed the control diet (60%). Generally, feeding concentrate at 1.3 or 1.8% BW and supplementing with soybean meal or fish meal resulted in pH and concentrations of NH3 N and VFA similar to those observed on the all silage diet. Feeding concentrate at 1.3 or 1.8% BW and supplying fish meal or soybean meal did not change feed utilization enough to increase milk production in low producing cows compared with an all silage diet. 相似文献
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发酵非常规蛋白饲料对肉仔鸡生长性能和养分消化率的影响 总被引:1,自引:0,他引:1
研究了发酵非常规蛋白饲料(后称发酵饲料)对肉仔鸡生产性能和养分消化率的影响,选用250只肉仔鸡,随机分为5个处理组,试验期6周。A组饲料为基础玉米豆粕日粮,B组添加10%未发酵饲料替代部分豆粕,处理组C、D、E分别添加发酵饲料5%、10%、15%替代部分豆粕。处理组平均日采食量、平均日增重均高于B组,与A组相比差异不显著(P>0.05),D组与A组最为接近。通过代谢试验可得出,发酵饲料与未发酵饲料相比粗蛋白质消化率显著增加(P<0.05),氨基酸消化率差异不显著(P>0.05)。因此,在发酵饲料替代10%豆粕是可行的。 相似文献
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去皮豆粕的生产与应用 总被引:5,自引:1,他引:5
在大豆浸出制油过程中,通过增加脱皮工艺,可得到高蛋白去皮豆粕.将豆粕与收集的豆皮分别粉碎后,把豆皮按需添加至去皮豆粕中,可得到不同粗蛋白(CP)含量的的等级豆粕.影响脱皮效果的因素主要有干燥温度、破碎辊间隙、吸风量、豆皮筛网规格等.高蛋白豆粕比普通豆粕具有较高的营养与使用价值,随着饲料工业的发展,我国高蛋白豆粕在饲料中所占比例将逐步增加. 相似文献
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优质蛋白饲料资源短缺成为影响我国粮食安全的重要变量。我国粮油加工副产物资源丰
富,但是饲用价值偏低,通过生物发酵、酶解、合成生物学等现代生物技术对这些资源进行加工
处理,能实现资源提质增效,达到替代大豆粕的目的。本文重点综述了发酵饲料、酶解饲料和菌
体蛋白饲料的生产工艺、饲用价值以及在豆粕减量替代研究中的应用效果,同时介绍了微生物吸
附、降解以及生物酶在脱除真菌毒素上的研究进展,最后对生物发酵饲料的开发、产业化应用、
标准制定、行业监管等方面提出了研究展望。本文可为生物技术在粮油饲料资源增值上的应用提
供有力指导。 相似文献
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Holstein cows in early lactation, producing about 30 kg/d of milk, were fed high energy diets containing 5% Megalac. Three protein treatments, soybean meal diet (16% CP), fish meal diet (16% CP), and soybean meal-fish meal diet (20% CP) were compared in a change-over design. Digestibilities of DM, gross energy, CP, and ADF were not affected significantly by protein treatments. The fish meal diet decreased DMI but increased milk and SCM production compared with the soybean meal diet. Daily production of milk, SCM, and milk components (fat, protein, and lactose) were highest and BW gain lowest for the high protein soybean meal-fish meal diet. The fish meal and soybean meal-fish meal diets increased fat percentage but decreased lactose percentage of milk compared with soybean meal diet. This suggests that, for each diet, the energy supply was adequate, and the observed changes were the effects of protein (i.e., AA) supply to the cows. Thus, there seems to be good reason to feed a good quality undegradable protein like fish meal to cows producing more than 30 kg/d of milk. 相似文献