大麦内源酶去除大豆植酸的正交实验研究

利用发芽大麦的植酸酶去除大豆中的植酸。实验表明,将发芽3d的大麦与浸泡1d的大豆以6∶4的比例混合粉碎后,在60℃,pH6.0条件下酶解3h,麦豆混合物中植酸去除率可达96%以上。     

大麦内源酶去除大豆植酸的正交实验研究

利用发芽大麦的植酸酶去除大豆中的植酸。实验表明,将发芽3d的大麦与浸泡1d的大豆以6∶4的比例混合粉碎后,在60℃,pH6.0条件下酶解3h,麦豆混合物中植酸去除率可达96%以上。      

大麦内源酶去除大豆植酸的研究

利用发芽大麦的植酸酶去除大豆中的植酸。试验表明：将发芽3d的大麦与浸泡1d的大豆以6：4的比例混合粉碎后，在55-60℃，pH=5，5条件下酶解3h，麦豆混合物中植酸去除率可达93％以上。     

不同发芽条件对蚕豆植酸酶活性的影响

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.     

酶法降低糙米植酸含量工艺条件的优化

以糙米为研究对象，借助超声波强化传质过程，利用植酸酶降低糙米中植酸的含量，研究液料比、温度、pH值对植酸水解反应的影响，采用中心组合试验方案设计和响应面分析方法对植酸水解的工艺条件进行优化。研究结果表明，植酸水解工艺的优化条件为：pH值6．5，温度为53℃，液料比为10。     

内源性植酸酶对大豆乳、面团等食品中植酸的作用

天然植物食品中含有内源性植酸酶,一定条件下可以催化其中的植酸水解。实验表明,内源性植酸酶在对豆乳中的植酸进行水解时,45℃下24 h后植酸磷水解率达到了28.1%;内源性植酸酶在对面团中的植酸水解时,45℃下4 h后植酸磷水解率达到27.9%,而添加一定量酵母于面团中进行发酵处理,面团中植酸磷的水解率可以增至40.9%。所以,食品中内源性植酸酶对植酸的水解作用是存在的,但程度有限。     

工艺参数对发芽糙米中植酸含量的影响

研究发芽糙米生产过程中糙米所含抗营养因子植酸的变化规律,以发芽温度、发芽时间、浸泡时间、赤霉素浓度等工艺参数对产品植酸含量的影响进行了正交试验,试验结果表明:发芽温度和发芽时间对植酸含量的影响显著,发芽温度的提高和发芽时间的持续使糙米中植酸的含量逐步下降;通过发芽降低糙米植酸含量的最佳工艺参数组合为:发芽温度36℃、发芽时间34 h、浸泡时间12 h、赤霉素(GA3)浓度0.30 mg/L,此条件下发芽糙米产品中的植酸含量为3.22 mg/g.     

ICP-AES分析植酸酶对制麦过程中游离态金属离子含量的变化

运用电感耦合等离子体原子发射光谱法(ICP-AES)考察了外源添加植酸酶对大麦发芽过程中游离态K+、Na+、Ca2+、Mg2+、Zn2+含量的变化。实验发现:添加外源植酸酶能提高发芽过程中游离态金属离子的含量,K+、Na+、Ca2+、Mg2+、Zn2+含量同比可提高10.7%、23.4%、16.3%、8.0%、75.5%。通过比较金属离子含量的变化可以为制定合理的制麦工艺提供参考。     

ICP-AES分析植酸酶对制麦过程中游离态金属离子含量的变化

运用电感耦合等离子体原子发射光谱法（ICP-AES）考察了外源添加植酸酶对大麦发芽过程中游离态K+、Na+、Ca2+、Mg2+、Zn2+含量的变化。实验发现:添加外源植酸酶能提高发芽过程中游离态金属离子的含量,K+、Na+、Ca2+、Mg2+、Zn2+含量同比可提高10.7%、23.4%、16.3%、8.0%、75.5%。通过比较金属离子含量的变化可以为制定合理的制麦工艺提供参考。      

不同发芽条件对蚕豆植酸酶活性变化和性质的影响

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。     

外源性植酸酶在大豆乳中的应用

植物性食物中的植酸不能被单胃动物吸收,但是植酸酶能够水解植酸最终释放出肌醇和无机磷,供单胃动物吸收利用。本实验在研究温度、pH等因素对植酸酶活性影响的基础上,确定植酸酶催化植酸的水解条件为温度45℃、pH4.5、时间2h、酶添加量300FTU/kg。将植酸酶添加到大豆乳中,对大豆乳中植酸/植酸盐进行水解,分析发现大豆乳中有机磷的水解率高达82.9%;植酸酶对大豆乳中植酸/植酸盐的水解作用,对提高大豆乳的营养价值具有重要意义。     

Production of phytase by Aspergillus ficuum and reduction of phytic acid content in canola meal

Production of the phytase (EC 3.1.3.8) from Aspergillus ficuum in a submerged batch process was inhibited by high concentrations of glucose. The inhibition was overcome by applying a fed batch technique in the production of the enzyme. Tests carried out at different oxygen concentrations revealed that aeration had a beneficial effect on the production of the enzyme. The enzyme showed an optimum pH and temperature of 5·0 and 60°C, respectively. Preincubation of the enzyme preparation at 60°C resulted in relatively fast denaturation of the enzyme. Upon storage at 4°C it lost only 15% of its activity in 5 weeks. Aspergillus ficuum also produced phytase when grown on canola meal by a solid state technique. The enzyme catalysed degradation of the phytic acid present in the meal and completely eliminated it, rendering the commodity more suitable for animal feed. An apparent 10% increase in protein content of the canola meal was noted as a result of the growth of the microorganism.     

目前国内外植酸酶研究进展

详细地介绍了植酸(盐)生化生理特性，综述了国内外植酸酶研究的概况及植酸酶添加到饲料中的主要功能，也指出了当前研究植酸酶的攻关方向。     

植酸酶在食品和医药方面的应用展望

从植酸及其盐类的抗营养作用出发，简单介绍了植酸酶的分类，来源，着重阐述了植酸酶在食品和医药方面应用及所面临的困难和应用前景。     

植酸酶在米糠谷蛋白提取中应用的研究

以脱脂米糠分级去除清、球、醇溶蛋白后的残渣为原料,以植酸去除率为评价指标,以酶解温度、酶解p H、酶解时间和植酸酶添加量为影响因素进行单因素实验。在此基础上,根据Box-Benhnken中心组合实验设计原理,设计三因素三水平响应面优化实验。在分析各个因素的显著性和交互作用后,得出去除植酸的最佳工艺条件为:植酸酶添加量2.5 U/g,p H5.6,酶解温度48℃,酶解时间3 h,此条件下,模型实际值为85.47%。在最优植酸酶解条件下,米糠谷蛋白的提取率和纯度分别提高了24.53%和10.16%,与此同时,谷蛋白中植酸含量降低了93.2%,溶解性也一定程度上得到了改善。      

The degradation of phytate by microbial and wheat phytases is dependent on the phytate matrix and the phytase origin

BACKGROUND: Phytases increase utilization of phytate phosphorus in feed. Since wheat is rich in endogenous phytase activity it was examined whether wheat phytases could improve phytate degradation compared to microbial phytases. Moreover, it was investigated whether enzymatic degradation of phytate is influenced by the matrix surrounding it. Phytate degradation was defined as the decrease in the sum of InsP₆ + InsP₅. RESULTS: Endogenous wheat phytase effectively degraded wheat InsP₆ + InsP₅ at pH 4 and pH 5, while this was not true for a recombinant wheat phytase or phytase extracted from wheat bran. Only microbial phytases were able to degrade InsP₆ + InsP₅ in the entire pH range from 3 to 5, which is relevant for feed applications. A microbial phytase was efficient towards InsP₆ + InsP₅ in different phytate samples, whereas the ability to degrade InsP₆ + InsP₅ in the different phytate samples ranged from 12% to 70% for the recombinant wheat phytase. CONCLUSION: Wheat phytase appeared to have an interesting potential. However, the wheat phytases studied could not improve phytate degradation compared to microbial phytases. The ability to degrade phytate in different phytate samples varied greatly for some phytases, indicating that phytase efficacy may be affected by the phytate matrix. Copyright © 2011 Society of Chemical Industry     

The effect of germination on the phytase activity,phytate and total phosphorus contents of some Nigerian‐grown grain legumes

BACKGROUND: Grain legumes are under‐exploited as possible sources of phytase for the poultry industry. The current study was conducted to assess the effect of germination on phytase activities, phytate and total phosphorus content in samples of Nigerian‐grown grain legumes. The legumes screened were African yambean (AYB, Sphenostylis stenocarpa), lima bean (Phaseolus lunatus), pigeon pea (Cajanus cajan), cowpea (Vigna unguiculata) and groundnut (Arachis hypogea). RESULTS: Phytase activity was low in AYB, lima bean and pigeon pea but high in cowpea and groundnut. Phytate content ranged between 3.01 g kg^?1 and 8.95 g kg^?1 while total phosphorus content ranged between 2.63 g kg^?1 and 5.93 g kg^?1. The grain legumes with higher phytase activity recorded the lowest phytate and phosphorus content. During germination there was an initial 4‐fold to 35‐fold increase in phytase activity after 6–7 days of germination followed by a decrease until 10 days (P < 0.05). The increase in phytase activity during germination was accompanied by a significant reduction in phytate (P < 0.05) and a small but significant increase in total phosphorus. CONCLUSION: The increase in phytase activity and the accompanying decrease in phytate content could have a positive implication for the nutrition of poultry and ruminants and for the environment. Copyright © 2010 Society of Chemical Industry     

辐照对大麦发芽的影响

该文介绍了3个品种的大麦干种子经Co60辐照后的发芽情况。结果表明,在0kGy~3kGy低剂量辐照下,对相同品种大麦辐照的发芽率几乎没有影响,影响大麦发芽率的因素主要为大麦的质量,而不是辐照。     

Phytate content and phytate degradation by endogenous phytase in pea (Pisum sativum)

In order to rapidly reduce the content of inositol tri–hexaphosphates in pea flour by action of the endogenous phytase, raw materials as well as incubation conditions have been evaluated. The phytate (inositol hexaphosphate) content was analysed in 27 pea varieties; the influence of storage time and the difference in phytate content between the germ and the cotyledon were determined. Furthermore, degradation of inositol phosphates by the endogenous phytase enzyme was studied in pea flour, germ and cotyledon. To find the maximum phytate degradation, the effects of temperature and pH during pea flour incubation were investigated. The most efficient phytate degradation in pea flour incubation was achieved at pH 7.5 and 45 °C. At this condition an almost complete degradation of phytate and a 66% reduction in the sum of inositol hexa‐, penta‐, tetra‐ and triphosphates were reached in 10 h. The storage time of pea seeds or removal of the germ did not have a major effect on the phytate content. Since several inositol pentaphosphate isomers were produced during phytate degradation, it can be concluded that peas contain several phytate‐degrading enzymes, or one phytate‐degrading enzyme with unspecific initial hydrolysation pattern. © 2001 Society of Chemical Industry.