共查询到17条相似文献,搜索用时 109 毫秒
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植酸酶作为饲用酶制剂被广泛应用于环保型饲料中,主要介绍了植酸酶对家禽生产性能、家畜生产性能的影响,以及植酸酶对氮、磷代谢和植酸酶对矿物质元素代谢的影响,最后对植酸酶发展前景进行了展望。 相似文献
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黑曲霉(A.niger)496 1菌株所产胞外植酸酶,经透析浓缩、DEAE cellulose离子交换层析及SephadexG 75,Sephacryl100凝胶过滤,获得了2个植酸酶,其相对分子质量分别为64200及41100.该2个植酸酶的最适pH分别为6.0和3.0,最适温度分别为55℃和40℃.初步确定一个是中性植酸酶,另一个为酸性植酸酶. 相似文献
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本研究选用七种不同植酸酶产品,通过粒度分布、水分、灰分、容重、耐热性、体外对植酸磷的释放效应等方面进行不同植酸酶物理特性的评估,同时在零无机磷的极端饲料配方下,观察不同植酸酶对肉鸡生长性能和胫骨发育的影响,以综合评估不同植酸酶的功效。结果表明:不同植酸酶的几何平均粒径无差异(P0.05),但算术平均粒径和粒度模数差异显著(P0.001),植酸酶A、B、F和G颗粒可能更细更集中;水分、灰分含量和容重差异显著(P0.05),植酸酶A和F更有益于在配合饲料中的混合和均匀分布;不同植酸酶耐热性能不同(P0.001),A和G表现更好;体外酶解释放磷的效果差异极显著(P0.01),植酸酶A的体外磷释放率较高;相比于其他植酸酶,肉鸡饲粮中添加植酸酶A,能够极显著提高肉鸡采食量(P0.01),且有提高期末体重和平均日增重的趋势(P=0.083)。此外,处理A表现出了更大的肉鸡胫骨重(P0.05)。不同植酸酶产品理化特性比较及在肉鸡上的实际饲喂效果存在差异,可见,对植酸酶的评估不能从单一方面(如耐热性)考虑,应综合植酸酶的粒度分布和均匀度、耐热性能、肉鸡生长性能和养分释放效应以及胫骨发育等指标科学系统评估。 相似文献
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植酸酶研究进展及其在饲料工业中的应用 总被引:22,自引:1,他引:21
综述了植酸酶的种类、来源、酶学特性、酸活的测定方法、当前国内外对植酸酶高产菌株的研究进展,以及应用植酸酶制剂对饲料营养价值与畜禽生产性能的影响。 相似文献
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植酸的抗营养作用及植酸酶在饲料中的应用(二) 总被引:5,自引:1,他引:4
5应用植酸酶制剂应考虑的几个具体问题5.1动物种类及年龄植酸酶制剂仅适用于各种非反刍动物。目前研究报道较多的是将植酸酶制剂用于鸡和猪。动物消化道中植酸的降解实际上有3种来源的植酸酶参与,即饲料中的植酸酶(包括植物性饲料中存在的植酸酶和添加的外源性植酸... 相似文献
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Birgit Zimmermann Hans‐Joachim Lantzsch Rainer Mosenthin Franz‐Josef Schner Hans Konrad Biesalski Winfried Drochner 《Journal of the science of food and agriculture》2002,82(11):1298-1304
Two experiments with a total of 76 growing pigs (average initial body weight 16.6 kg) were conducted to compare the efficacy of cereal phytases (wheat and rye) and supplemented microbial phytase (Natuphos®). Using the slope ratio technique, the dose–response relationship between five levels of phytase (0, 50, 100, 150 and 200 U kg?1) and the apparent absorption of phosphorus (P) within each source of phytase was calculated. Graded phytase levels in the diets were obtained by adding increasing amounts of microbial phytase or phytase‐containing wheat (Exp 1) or rye (Exp 2) to phytase‐inactivated basal diets at the expense of phytase‐inactivated wheat (Exp 1) or rye (Exp 2). Except for wheat phytase, addition of phytase to the basal diets increased (P < 0.05) apparent P absorption, with microbial phytase being more efficient (P < 0.05) than cereal phytase. There were no significant differences in apparent P absorption between the wheat‐ or rye‐based diets when either microbial or cereal phytases were supplemented from 0 to 200 U kg?1. It could be derived from the results of this study, by means of regression analysis, that the efficacy of cereal phytases was 40% compared to microbial phytase. © 2002 Society of Chemical Industry 相似文献
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Phytase in non‐ruminant animal nutrition: a critical review on phytase activities in the gastrointestinal tract and influencing factors
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Yueming Dersjant‐Li Ajay Awati Hagen Schulze Gary Partridge 《Journal of the science of food and agriculture》2015,95(5):878-896
This review focuses on phytase functionality in the digestive tract of farmed non‐ruminant animals and the factors influencing in vivo phytase enzyme activity. In pigs, feed phytase is mainly active in the stomach and upper part of the small intestine, and added phytase activity is not recovered in the ileum. In poultry, feed phytase activities are mainly found in the upper part of the digestive tract, including the crop, proventriculus and gizzard. For fish with a stomach, phytase activities are mainly in the stomach. Many factors can influence the efficiency of feed phytase in the gastrointestinal tract, and they can be divided into three main groups: (i) phytase related; (ii) dietary related and (iii) animal related. Phytase‐related factors include type of phytase (e.g. 3‐ or 6‐phytase; bacterial or fungal phytase origin), the pH optimum and the resistance of phytase to endogenous protease. Dietary‐related factors are mainly associated with dietary phytate content, feed ingredient composition and feed processing, and total P, Ca and Na content. Animal‐related factors include species, gender and age of animals. To eliminate the antinutritional effects of phytate (IP6), it needs to be hydrolyzed as quickly as possible by phytase in the upper part of the digestive tract. A phytase that works over a wide range of pH values and is active in the stomach and upper intestine (along with several other characteristics and in addition to being refractory to endogenous enzymes) would be ideal. © 2014 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献
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Abstract: In this study, alkaline phytase was added to whole‐wheat bread and the phytate content and mineral profiles were compared to commercially available acidic phytase. At neutral pH, some phytate (approximately 20%) was degraded by endogenous phytase in wheat flour, while 40% of phytate was hydrolyzed by alkaline phytase DS11 and a 35% reduction was observed with acidic phytase. Most of the enzymatic activity occurred during the proofing stage, and the rate of reaction depended on pH. DS11 phytase effectively degraded the phytate level within a 30 min treatment at pH 7; however, at least 60 min was needed with acidic phytase to achieve the same hydrolysis level. Mineral profiles were also dramatically affected by the phytate reduction. The biggest increase was observed in Fe2+ by the phytase treatment. The Fe2+ content increased 10‐fold at pH 7 and 8‐fold at pH 5 with alkaline phytase DS11. Alkaline phytase DS11 was shown to be effective at phytate reduction in whole‐wheat bread preparation. Additionally, phytate degradation enhanced the mineral availability of bread. 相似文献
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以蚕豆为试材,研究了发芽过程中植酸酶在蚕豆不同部位的变化和性质。发芽蚕豆不同部位植酸酶活性呈现先高后低的变化趋势,子叶植酸酶在发芽第6天达到最高值。超声波处理对发芽蚕豆胚根和子叶植酸酶活性有一定促进作用,其中以15min超声波处理对胚根植酸酶活性影响最大,5min处理、10min处理和15min处理均对子叶植酸酶活性有显著影响。在发芽过程中不同光照对蚕豆进行处理,不论胚根、子叶还是胚芽,黑暗处理植酸酶活性高于光照处理。核酸抑制剂放线菌素(Act-D)和蛋白质抑制剂环已酰胺(CHM)对发芽蚕豆胚根、子叶和胚芽中的植酸酶活性有一定影响,其中以CHM的抑制效果最为明显。 相似文献
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A fungus producing high levels of phytase was isolated from air and identified as Cladosporium sp. The phytase production was stimulated by phytate in the medium used. The maximum production of phytase (108 U/ml) occurred in a medium containing 1.0 g of phytate per 100 ml. The phytase was purified to electrophoretic homogeneity by ion-exchange chromatography and gel filtration. Based on SDS-PAGE analysis, the molecular weight of the purified phytase was calculated to be approximately 32.6 kDa, and the narrow protein band indicated that this phytase is not glycosylated. The phytase has an optimum pH of 3.5, and an optimum temperature of 40 degrees C. The phytase activity was stimulated by 2-mercaptoethanol and dithiothreitol, and inhibited by Ba2+, Pb2+, iodoacetate, p-chloromercuribenzoate and phenylmethylsulfonyl fluoride. The phytase displayed high affinity for phytate and the Km was 15.2+/-3.1 microM. NMR analyses (1D and 2D) indicated that the end hydrolysis product of phytate was myo-inositol 1,2,5-triphosphate. 相似文献
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以蚕豆为试材,研究发芽过程中植酸酶在蚕豆不同部位的变化和性质.发芽蚕豆不同部位植酸酶活性呈现先高后低的变化趋势,子叶植酸酶在发芽第6天达最高值.超声波处理对发芽蚕豆胚根、子叶和胚芽植酸酶活性有一定促进作用,其中以15min超声波处理对胚根和胚芽植酸酶活性影响最大,5min处理、10min处理和15min处理均对子叶植酸酶活性有显著影响.在发芽过程中不同光照对蚕豆进行处理,不论胚根、子叶还是胚芽,黑暗处理植酸酶活性高于光照处理.核酸抑制剂放线菌素(Act-D)和蛋白质抑制剂环已酰胺(CHM)对发芽蚕豆胚根、子叶和胚芽中的植酸酶活性有一定影响,其中以CHM的抑制效果最为明显. 相似文献