饲料蛋白酶的最新研究与应用进展
|
摘要
蛋白质是动物养殖中非常重要的营养元素之一。更好的消化利用蛋白质,促进其它养分的充分利用,提高生长性能减少环境污染。因此,以饲料为底物最优化筛选而得到的蛋白酶会大大提高饲料中蛋白质的营养功效。本文将讨论饲料用偏碱性蛋白酶(EC 3.4.21.-)的特点和作用机理,主要包括以下方面:(1)其底物选择范围广,可水解不同来源的饲料蛋白质。(2)在不同的肠道pH值范围均具有活性:在小肠中性和碱性pH值范围活性最高,在胃中酸性pH值范围仍然具有较高活性。(3)在功能上与动物内源蛋白质消化酶具有互补性,可将动物内源蛋白消化酶不易降解的蛋白肽键有效降解。(4)不受植物原料中(如豆粕)胰蛋白酶抑制因子的影响。(5)可降解蛋白类抗营养因子(如胰蛋白酶抑制因子、植物凝聚素),从而降低其对动物生长性能的负面影响。(6)偏碱性蛋白酶与其它市售饲料酶具有协同作用。(7)可广泛应用到禽和猪饲料中,改善畜禽的生长性能。
Protein is one of the indispensable nutrients in animal feed. Better digestion and utilization ofprotein will also help to promote the full utilization of other feed nutrients, thus improving animalgrowth, performance and reducing environment pollution. This paper presents and discusses our recentdata demonstrating why our newly developed slightly alkaline protease(EC 3.4.21.-) is better for thesepurposes. These include:(1) Having a wide substrate specificity and hydrolyzing feed proteins from vari-ous sources.(2) Being active over a wide pH range, most active in the neutral and alkaline pH ranges inthe small intestine and also having activity in the acidic pH of the stomach.(3) Being complementary inaction mode to the animals' own digestion proteases with the ability to hydrolyze peptide bonds that arenot easily degraded by their endogenous proteases.(4) Being not susceptible to trypsin inhibitors foundin plant-based feed materials such as soybean.(5) Capable of potentially degrading anti-nutritional fac-tors such as trypsin inhibitors and phytoagglutinins, thus reducing their negative impact on animal per-formance.(6) Having synergetic effects with other feed enzymes in efficiently utilizing feed nutrients.(7) Having been demonstrated to improve the performance of both poultry and swine in animal trials.
Protein is one of the indispensable nutrients in animal feed. Better digestion and utilization ofprotein will also help to promote the full utilization of other feed nutrients, thus improving animalgrowth, performance and reducing environment pollution. This paper presents and discusses our recentdata demonstrating why our newly developed slightly alkaline protease(EC 3.4.21.-) is better for thesepurposes. These include:(1) Having a wide substrate specificity and hydrolyzing feed proteins from vari-ous sources.(2) Being active over a wide pH range, most active in the neutral and alkaline pH ranges inthe small intestine and also having activity in the acidic pH of the stomach.(3) Being complementary inaction mode to the animals' own digestion proteases with the ability to hydrolyze peptide bonds that arenot easily degraded by their endogenous proteases.(4) Being not susceptible to trypsin inhibitors foundin plant-based feed materials such as soybean.(5) Capable of potentially degrading anti-nutritional fac-tors such as trypsin inhibitors and phytoagglutinins, thus reducing their negative impact on animal per-formance.(6) Having synergetic effects with other feed enzymes in efficiently utilizing feed nutrients.(7) Having been demonstrated to improve the performance of both poultry and swine in animal trials.
引文