【作者】 赵晓芳；

【导师】 林海； 张宏福；

【作者基本信息】 山东农业大学 ， 动物营养与饲料科学， 2003， 硕士

【摘要】 随着我国畜牧业的快速发展，蛋白质饲料短缺现象越来越严重。为开发新的蛋白质资源，本课题对味精菌体蛋白的提取工艺、主要提取方法以及味精菌体蛋白利用的经济效益和环境效益进行了调研；对味精菌体蛋白的常规营养成分、真蛋白质含量、各种矿物元素以及重金属含量进行了测定；并通过代谢试验测定了鸡味精菌体蛋白的表观代谢能、氨基酸的消化率，为开发利用味精菌体蛋白这种非常规蛋白饲料提供科学依据。现将论文简述如下：第一章： 本文对味精废液的特性，味精菌体蛋白的产量、提取工艺、主要提取方法以及开发利用菌体蛋白的经济效益和环境效益进行了综述。味精菌体蛋白的主要提取工艺有三种，分别为：从味精发酵液中直接提取、等电废液中提取和等电离交废液中提取，其中以第三种最为常用。主要提取方法有高速离心、超滤、加热沉淀和絮凝沉淀或气浮，其中以絮凝法最为常用，采用絮凝法提取味精菌体蛋白时，絮凝剂的选择和絮凝条件的控制非常重要。开发利用味精菌体蛋白，不但可缓解我国蛋白质饲料短缺现象，还可减轻对环境的污染，具有重大的经济效益和环境效益。第二章：本试验选择了四种有代表性的味精菌体蛋白，对其常规营养成分、真蛋白含量、氨基酸含量、各种矿物元素、pH值以及重金属含量进行测定。结果表明，由味精废液中提取出的味精菌体蛋白的粗蛋白含量非常高，甚至超过鱼粉的粗蛋白含量，但真蛋白含量、氨基酸含量相对较低，氨基酸组成极不平衡，谷氨酸含量很高，胱氨酸、赖氨酸含量较低。不同厂家味精菌体蛋白中，氨基酸组成差别很大，以Ⅳ的氨基酸组成最为平衡，理想蛋白水平最高。味精菌体蛋白还含有丰富的矿物元素，但存在钙少磷多的现象，且钙磷总体水平较低。除汞含量较高外，味精菌体蛋白中其它重金属含量均较低，不会对动物的安全造成威胁。第三章：选用体重为2.5kg左右（2658±256g）、健康、无强饲反应的农大褐成年公鸡15只，随机分成5组，每组3只，采用5×5拉丁方设计，运用强饲－排空法测定味精菌体蛋白的表观代谢能。结果表<WP=5>明，味精菌体蛋白的总体水平较低，其中Ⅳ的表观代谢能最高，为2887.5cal/g，Ⅰ的表观代谢能最低，为1443.3cal/g，Ⅳ味精菌体蛋白的表观代谢能是Ⅰ的两倍。味精菌体蛋白的表观代谢能两两之间均有显著差异（p<0.05）或极显著差异（p<0.01）。第四章：选用体重2.5kg左右（2695±176g）、健康去盲肠农大褐成年公鸡20只，随机分成5组，每组4只。采用5×5拉丁方设计，运用强饲－排空法测定了味精菌体蛋白的氨基酸消化率，结果表明，味精菌体蛋白的表观氨基酸消化率、真氨基酸消化率总体水平都比较低。表观氨基酸消化率都低于80％。四种味精菌体蛋白中，Ⅳ的真氨基酸消化率最高，必需氨酸消化率大多在80％以上，而其余三种味精菌体蛋白的真氨基酸消化率都在80％以下。味精菌体蛋白的多数氨基酸消化率两两之间差异显著（p<0.05）或极显著（p<0.01）。除Ⅰ和Ⅲ的蛋氨酸、Ⅰ的色氨酸、Ⅱ和Ⅲ的丙氨酸、Ⅲ的甘氨酸的表观消化率与真消化率之间差异不显著（p>0.05），其余氨基酸的表观消化率与真消化率差异显著（p<0.05）或极显著(p<0.01)。更多还原

【Abstract】 In order to exploit new protein resources, this paper investigated the technology and the methods of collecting glutamate thalli protein and its ecnomic benefits and envorimental benefits of exploring glutamate thalli protein. The routine nutrients, true protein content, mineral content and heavy metal contents in the glutamate thalli protein of sampled from four factories were determined. Furthermore, apparent metabolitic energy (AME) and amino acid digestibility of glutamate thalli protein were determined by metabolitic trial. The results of this paper are summarized as follows:The first, this paper investigated the character of monosodium glutamate waste water, output of glutamate thalli protein, the technology and methods of collecting glutamate thalli protein in China. There are four kinds of methods of extracting glutamate thalli protein: high-speed centrifuge, ultrafiltration, heat and precipitate, flocculate and precipitate or air floatation, but the fourth is main method used in factories in China. The choice of flocculant and reactive terms control are very important. Exploiting and utilizing glutamate thalli protein can not only alleviate the shortage phenomenon of protein feedstuffs in our country, but also lighten the pollution of the environment, have great economic benefits and environmental benefit.The second, the routine nutrients, true protein, amino acid, minerals, pH value and heavy metal contents in the glutamate thalli protein were determined. The results indicated the glutamate thalli proteinhas very high crude protein content, even surpassing that of fish meal, but its true protein content, amino acid content are relative low, amino acid constitute of glutamate thalli protein is imbalance. Among all the amino acids, the content of Glutamic acid is the highest, however, that of Cystine is the lowest. There are plentiful minerals in glutamate thalli protein, but calcium and phosphorus<WP=7>contents are low, morever the ratio of calcium and phosphorus is not proper. The heavy metal elements contents are relative low and safe for animals except mercury.The third, 15 nongdahe adult roosters which its` average weight is 2658g were divided into 5 groups at random, 3 roosters every group. The trial use 5 ×5 latin design to determine the AME of glutamate thalli protein with forcefeeding-fasting method. The results revealed that the AME of glutamate thalli protein is low as a whole, the AME of Ⅳ(2887.5Cal/g) is highest, and that of l is the lowest(1443.3Cal/g). There is significant difference between them.The fourth, 20 nongdahe cecectomized adult roosters were divided 5 groups to determine the amino acid digestibility of glutamate thalli protein, 4 roosters every group. The results indicated that the apparent amino acid digestibility and true amino acid digestibility of the four kinds of glutamate thalli protein is relative low. Almost all the apparent digestibility of glutamate thalli protein is below 80%. Most of essential amino acid true digestibility of Ⅳ is above 80%, while others is below 80%. Expect the Cys and Arg true digestibility of Ⅳ is equivalent to fish meal, others are far below that of fish meal and soybean meal. There is significant difference between them (p<0.05) or (p<0.01). There are significant difference between apparent digestibility and true digestibility for almost all the amino acids, expect Met, Trp ofⅠ, Met, Ala, Gly of Ⅲ and Ala of Ⅱ.更多还原