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1.
Decreased iron and zinc bioaccessibility, caused by the anti-nutrient phytic acid, is one of the leading reasons for micronutrient deficiency-related disorders. Biofortification of wheat with phytase gene to enhance iron and zinc bioaccessibility appears to be a fitting solution for this problem, especially in developing countries where most of the population belongs to the lower economic sector. However, societal views on crops, particularly crops that are genetically modified (GM) to express a new trait, needs to be changed. Risk assessment of GM crops can play a crucial role in fostering positive public perception, since it is imperative to ensure safety before allowing human consumption. The present study performed compositional and morphological risk assessment of T3 and T4 generations of phytase transgenic wheat by comparing their biochemical and morphological traits. Transgenic plants were analysed for their carbohydrate, protein, starch and phytic acid content along with iron bioaccessibility, zinc bioaccessibility and phytase enzyme activity. Morphological traits studied included plant height, seed number, seed weight and spike number. No significant differences were observed for carbohydrate, protein, starch content and for morphological traits; however, a significant increase was observed in phytase activity as well as iron and zinc bioaccessibility, which correlated with a significant decrease in phytic acid. These results demonstrate that phytase transgenic wheat is as native as local wheat varieties and can potentially increase iron and zinc bioaccessibility. 相似文献
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大量研究结果显示,植酸酶在动物生产和环境保护方面具有很好的应用前景。本文就植酸酶的种类和来源、理化特性、作用机理以及在畜牧业上的应用作一简要综述。 相似文献
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将体重相近的60头15kg左右的杜长大仔猪分为5个处理(对照组、AP降低0.1%、AP降低0.12%、AP降低0.1%+酶、AP降低0.12%+酶),每个处理3个重复,每重复4头仔猪。研究结果表明:曰粮有效磷水平和植酸酶对仔猪生长、料重比都有显著的影响(P〈0.05),与对照组相比,当日粮有效磷水平降低0.1%,仔猪体重、日增重会显著降低,而料重比显著上升;当有效磷降低0.1%添加植酸酶时,仔猪体重、日增重会显著增加,而料重比显著下降;当日粮有效磷降低0.12%时,不论加酶与否,其体重、日增重都会显著下降,而料重比会显著增加。 相似文献
5.
Feng Wang Yu-Hong Yang Zhi-Zhong Han Hong-Wei Dong Cheng-Hui Yang Zuo-Yu Zou 《Aquaculture International》2009,17(2):143-157
Rainbow trout were fed a diet containing phytase-sprayed and phytase-pretreated soybean meal with different phytase levels.
The single factor random block design was used to analyze the effects on rainbow trout of dietary phytase supplementation
on growth performance, nutritional ingredient digestibility and nutrient excretion. After 90 days, the results showed that
feed conversion ratio (FCR) and protein efficiency ratio (PER) were significantly improved and specific growth rate (SGR)
was not affected by spraying phytase, but SGR, FCR and PER were not significantly improved by phytase pretreatment. A digestibility
trial conducted after the feeding trial showed that apparent digestibility coefficient (ADC) of diet protein and minerals
was increased with phytase supplementation. However, there was a negative effect of phytase on the ADC of lipid. The excretion
experiment showed that the supplementation of phytase resulted in decreased nutrient excretion in feces, but lipid excretion
was slightly increased with phytase supplementation. In addition, the results of P excretion and ADC of P analyzed by t-test showed that phytase pre-treatment method should be a more rational method than the spraying method. The results of SGR,
ADC of P and P excretion analyzed by quadratic regression indicated that 2,000–3,000 U/kg levels by the spraying method could
be a rational range of phytase supplementation, and about 1,000 U/kg should be an optimal level by the pretreatment method.
Thus, use of phytase in rainbow trout feeds can have economic and environmental benefits. 相似文献
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Two consecutive feeding trials were conducted to determine the optimum dietary level of the cottonseed and soybean meal (CS) for replacement of fish meal (FM) in diets for juvenile and ongrowing parrot fish with or without iron and phytase. In experiment I, juvenile parrot fish (BW: 3.17 g) were fed one of six experimental diets for 12 weeks which were formulated to replace FM protein by equal proportion (1:1, w:w) of CS at 0, 10, 20, 30, 40, or 50% (designated as CS0, CS10, CS20, CS30, CS40, or CS50, respectively). In experiment II, ongrowing parrot fish (BW: 55 g) were fed one of five experimental diets for 9 weeks. The experimental diets were formulated to replace FM protein by CS at 0, 20, or 30% (designated as CS0, CS20, or CS30, respectively) and to include ferrous sulfate (0.1 and 0.2%) and phytase into the CS20 and CS30 diets (CS20 + Fe&P and CS30 +Fe&P, respectively). Results from the two feeding trials indicated that the CS could replace up to 20% FM protein in diets for juvenile parrot fish (3–22 g) and up to 30% in ongrowing (55–120 g) parrot fish. The supplemental effect of iron and phytase was not significant on growth performance. Total or each gossypol enantiomer concentration in the liver increased as the level of dietary cottonseed meal increased. However, gossypol in the liver of fish fed diets supplemented with iron was not detected. The dietary supplementation of CS significantly reduced the levels of plasma triacyglycerols and total cholesterol. The present study indicates that plant protein sources are better utilized in larger fish, and that up to approximately 30% FM protein could be replaced by CS with iron and phytase in the presence of supplemental lysine and methionine. 相似文献
7.
植酸酶对北京红鸡蛋用母雏生产性能及血液指标影响的研究 总被引:3,自引:0,他引:3
480只1日龄北京红鸡蛋用母雏随机分为8个处理组,每个处理4个重复,每个重复15只鸡。玉米-豆粕型试验日粮分为3个磷水平,即TP=0.5%、0.6%、0.7%,在TP=0.5%时,每公斤日粮分别添加500FTU、750FTU、1000FTU植酸酶,在TP=0.6%时,每公斤日粮分别添加500FTU、750FTU植酸酶。结果不同处理间0~6周龄雏鸡平均日增重差异极显著(P<0.01),而日饲料消耗量及饲料转化率差异不显著(P>0.05):从血液指标看,不同处理间血磷、血钙、碱性磷酸酶(ALP)差异均不显著,但血磷低的处理组,一般ALP水平相对较高。 相似文献
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来源于Selenomonas ruminantium的高比活植酸酶基因在毕赤酵母中的高效表达 总被引:6,自引:1,他引:6
应用酶解效率更高的高比活植酸酶是进一步提高植酸酶发酵效价、降低植酸酶生产成本的有效途径。根据毕赤酵母对于密码子的选择偏向,对来源于原核瘤胃微生物Selenomonasruminantium的高比活植酸酶基因phyS进行了密码子优化,将优化后的植酸酶基因phyS(m)与未优化的phyS插入到毕赤酵母转移载体pPIC9中,转化毕赤酵母得到重组子,在摇瓶水平上,phyS(m)的表达水平比phyS高10倍。在5L发酵罐中,优化后的植酸酶基因phyS(m)其蛋白表达量达到4mgml-1发酵液,效价达到1.6×106I 相似文献