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用菠萝蛋白酶对醇法大豆浓缩蛋白进行酶法改性,提高醇法大豆浓缩蛋白的溶解性.在单因素分析的基础上采用响应面分析方法对酶解条件进行优化,酶解的最佳条件为pH6.5,反应温度48℃,底物浓度6%,加酶量607 U/g.此条件下水解4 h,水解度可达11.07%. 相似文献
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菠萝蛋白酶水解泥鳅蛋白制备ACE抑制肽的研究 总被引:1,自引:0,他引:1
为了探讨利用泥鳅蛋白制备功能性肽的可能性,采用高效液相色谱法测定泥鳅肉水解物对血管紧张素转换酶(ACE)的抑制作用,从胰蛋白酶、胃蛋白酶、菠萝蛋白酶、复合风味蛋白酶、复合蛋白酶5种酶中筛选出菠萝蛋白酶作为酶解泥鳅肉制备具有降血压活性水解物的适宜水解酶。在单因素试验的基础上,采用L9(34)正交试验设计对该酶的酶解条件进行优化。结果表明最佳水解条件为:温度55℃,固液比1:3,pH6.5,加酶量1000U/g pro,水解时间90min。在该条件下,水解物的ACE抑制率IC50值为0.0184mg/mL,ACE抑制肽的相对分子质量主要集中在924左右。 相似文献
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M. A. Mazorra-Manzano J. C. Ramírez-Suarez R. Y. Yada 《Critical reviews in food science and nutrition》2018,58(13):2147-2163
ABSTRACTProteins are a potential source of health-promoting biomolecules with medical, nutraceutical, and food applications. Nowadays, bioactive peptides production, its isolation, characterization, and strategies for its delivery to target sites are a matter of intensive research. In vitro and in vivo studies regarding the bioactivity of peptides has generated strong evidence of their health benefits. Dairy proteins are considered the richest source of bioactive peptides, however proteins from animal and vegetable origin also have been shown to be important sources. Enzymatic hydrolysis has been the process most commonly used for bioactive peptide production. Most commercial enzymatic preparations frequently used are from animal (e.g., trypsin and pepsin) and microbial (e.g., Alcalase® and Neutrase®) sources. Although the use of plant proteases is still relatively limited to papain and bromelain from papaya and pineapple, respectively, the application of new plant proteases is increasing. This review presents the latest knowledge in the use and diversity of plant proteases for bioactive peptides release from food proteins including both available commercial plant proteases as well as new potential plant sources. Furthermore, the properties of peptides released by plant proteases and health benefits associated in the control of disorders such as hypertension, diabetes, obesity, and cancer are reviewed. 相似文献
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María del Carmen Oliver-Salvador Zhirui Lian Richard A. Laursen Víctor M. Bolaños-García Manuel Soriano-García 《Food chemistry》2011
A new proteinase, mexicain-IV (MX-4), has been purified to homogeneity from the latex fruits of Jacaratia mexicana (formely Pileus mexicanus), a plant member of the Caricaceae family. MX-4 shows a Mr of 23.7 kDa, pI of 9.3 and maximum proteolytic activity on casein and BAPNA at pH 8.0–8.5 and pH 7.0–7.5, respectively. The amino acid sequence of MX-4 and its reversible inhibition by HgCl2 show that the proteinase belongs to the family of cysteine proteinases. This enzyme exhibits rather broad substrate specificity, although there seems to be a slight preference for cleavage of peptides having certain hydrophobic residues in the P2 position. Biochemical and circular dichroism studies revealed that this enzyme belongs to the α + β class of proteins, in agreement with the results obtained by X-ray crystallographic structure determination, and showed that MX-4 has a higher pH and thermal stability than other members of the Caricaceae family, including papain. These properties make this novel protease a suitable novel analytical tool for the proteomic analysis of peptide fragments of great potential interest in the food industry and other industries. 相似文献
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以干发酵肠为研究对象,在传统自然发酵的工艺基础上,以不同的组合方式添加菠萝蛋白酶、谷氨酰胺转氨酶和ZnSO4,比较这3种组合的发酵肠之间各项理化指标的差异。结果显示:随着发酵时间的延长,3组工艺发酵肠中的水分含量、pH值呈下降趋势;蛋白质、挥发性盐基氮(TVB-N)、氨基态氮及脂肪含量和过氧化值(POV)值逐渐升高。在发酵过程中,Ⅱ组(酶+ZnSO4)和Ⅲ组(加酶)总蛋白质含量低于Ⅰ组(传统工艺),挥发性盐基氮与氨基态氮含量高于Ⅰ组(传统工艺)。而Ⅱ组(酶+ZnSO4)和Ⅲ组(加酶)工艺相比较,Ⅱ组(酶+ZnSO4)pH值、蛋白质含量高于Ⅲ组(加酶),挥发性盐基氮和氨基态氮含量却相对较低。3种组合工艺发酵肠之间的POV值差异不显著。 相似文献
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本文研究不同浓度的Fe~(2+)和Fe~(3+)对菠萝蛋白酶活性和60℃下酶稳定性的影响,以及通过圆二色谱检测Fe~(2+)和Fe~(3+)对酶构象的变化,并初步探究EDTA-2Na结合超滤膜法在菠萝蛋白酶制备工艺中清除铁离子的应用效果。结果表明:Fe~(2+)浓度在0~0.75 mmol/L范围内,对菠萝蛋白酶活性有促进作用,以0.5 mmol/L促进效果最佳,但浓度大于0.75 mmol/L时,抑制酶活,且随浓度增加,抑制程度增强。Fe~(3+)对菠萝蛋白酶只有抑制作用,抑制程度与Fe~(3+)浓度成正比,且Fe~(3+)对酶的抑制作用强于Fe~(2+)。60℃下,Fe~(2+)在浓度为0.5 mmol/L对菠萝蛋白酶的稳定性表现出促进作用,延长了酶的半衰期。Fe~(3+)对酶的稳定性呈现抑制作用。Fe~(2+)和Fe~(3+)浓度大于0.5mmol/L时,随离子浓度的升高,对酶稳定性的抑制作用增强。采用圆二色谱检测酶的二级结构表明:Fe~(2+)和Fe~(3+)对酶抑制作用表现为α-螺旋含量下降,β-折叠和β-转角含量稍下降,无规卷曲含量明显提高。EDTA-2Na结合超滤膜法除铁的效果很明显,铁含量(干重)从291.63 mg/kg降低到142.99 mg/kg,铁离子去除率达50.97%,其酶活也由597.27 U/mg上升到808.52 U/mg,酶活提高了26.13%。 相似文献
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不同金属离子对菠萝蛋白酶活性及热稳定性的影响 总被引:3,自引:0,他引:3
该试验研究表明,Mg2+、Mn2+和Ca2+对菠萝蛋白酶的酶活性均有促进作用,且在浓度分别为4mmol/L,2mmol/L和2mmol/L最明显;Zn2+对菠萝蛋白酶的活性抑制作用明显,且随浓度的增大抑制作用越大。在60℃下Ca2+、Mn2+对菠萝蛋白酶的热稳定性具有促进作用,Ca2+浓度为3mmol/L时菠萝蛋白酶的半衰期延长了55min,增加了原菠萝蛋白酶的59.5%。Mn2+浓度为1mmol/L时半衰期延长了19.78min,增加了原菠萝蛋白酶的29%。Mg2+、Zn2+对菠萝蛋白酶的热稳定性没有明显的促进作用。 相似文献