A study was undertaken to investigate the production of amino acids from excess activated sludge (EAS) by enzymatic hydrolysis. Firstly, the protein was extracted from EAS. Secondly, the protein solution was further h...A study was undertaken to investigate the production of amino acids from excess activated sludge (EAS) by enzymatic hydrolysis. Firstly, the protein was extracted from EAS. Secondly, the protein solution was further hydrolyzed under free enzyme or immobilized enzyme. The reversed phase high performance liquid chromatography (RP-HPLC) and inductively coupled plasma emission spectrometer (ICP) were applied to determine the contents of amino acids and heavy metals, respectively. The effects of enzyme/substrate(E/S), pH, temperature, and reaction time were investigated in detail. The results indicated that, the optimum conditions for protein hydrolysis were temperature 55℃, pH 10, E/S 9 g/L, and reaction time 8 h, and the highest yield of amino acids was more than 10 g/100 g dry sludge (DS) under free enzyme. Moreover, the security and nutrition were taken into consideration. There were seven kinds of essential amino acids and ten non-essential amino acids in the raw amino acid (RAA) solution, and the contents of heavy metals were lower, living up to Hygienical standard for feeds (China). This technology widens the source of amino acids and makes the extraction of amino acids from EAS more economic and effective.展开更多
The recycling of waste from food processing is an important industrial procedure for obtaining protein sources with high added value.In this study,trout(Onchorynchus mykiss),anchovy(Engraulis encrasicolus),and whiting...The recycling of waste from food processing is an important industrial procedure for obtaining protein sources with high added value.In this study,trout(Onchorynchus mykiss),anchovy(Engraulis encrasicolus),and whiting(Merlangius merlangus)wastes were hydrolyzed.The hydrolyzation procedure was investigated under the optimum predicted conditions defined by time,temperature,and enzyme ratio(E/S)using alkaline protease(pH 8),Protamex(pH 7),and Flavourzyme(pH 7).The hydrolysis conditions that showed the best degree of hydrolysis(DH%)were optimized using response surface methodology(RSM)with the central composite design(CCD)and Box-Behnken design(BBD)models.The effects of three independent variables,temperature(40-60℃),time(1-8 h),and enzyme concentrations(1-2%),were examined for model optimization.It was determined that the DH%varies between 50.92%and 74.30% according to the type of fish waste and enzyme.The highest degree of hydrolysis was observed from trout waste(74.30%)and the lowest degree from whiting waste(50.92%)with Flavourenzyme.From this study,it has been shown that different degrees of hydrolysis and protein recovery can be obtained,depending on fish species,waste composition,enzyme type,and hydrolysis method.展开更多
为探究双酶不同酶解路线制得大米蛋白肽的性质差异,研究采用胰蛋白酶(A)和碱性蛋白酶(B)按不同酶解路线对大米蛋白进行酶解,制备了5种大米蛋白肽(A^(1)B^(1)、A^(1)B^(2)、A^(2)B^(1)、A^(1*)B^(2)、A^(2)B^(1*)),对其水解度、基本成分...为探究双酶不同酶解路线制得大米蛋白肽的性质差异,研究采用胰蛋白酶(A)和碱性蛋白酶(B)按不同酶解路线对大米蛋白进行酶解,制备了5种大米蛋白肽(A^(1)B^(1)、A^(1)B^(2)、A^(2)B^(1)、A^(1*)B^(2)、A^(2)B^(1*)),对其水解度、基本成分、氨基酸组成、微观结构、二级结构、分子量分布、风味和体外抗氧化活性等进行分析。结果表明,A^(2)B^(1)组的蛋白含量最高达到90.69%,肽含量高达72.73%;各路线的水解度大于17.60%,水解较为完全;微观结构均由不规则块状变为球体状,A1B2组和A^(1*)B^(2)组球体壁较厚,A^(2)B^(1)组和A^(2)B^(1*)组球体壁较薄,A^(1)B^(1)组为球体碎片;各路线的必需氨基酸含量比大米蛋白低,A1B2组必需氨基酸含量最高;二级结构以多种构象并存,各路线二级结构均以β-转角为主,占二级结构的44.62%~47.18%;各路线酶解产物多为低分子量的多肽,分子量低于5 k Da的多肽占92.09%~93.71%;A1B2样品鲜味最强,涩味最弱,A^(2)B^(1)样品咸味和苦味最弱;相比于A^(1)B^(1)组、A1B2组和A^(1*)B^(2)组,A^(2)B^(1)组和A^(2)B^(1*)组的抗氧化活性更强。通过对双酶不同酶解路线大米蛋白肽的性质研究,综合基本成分、肽含量、氨基酸组成、风味和抗氧化活性评价,A^(2)B^(1)组的品质最佳。展开更多
基金Innovation Program of Shanghai Municipal Education Commission,China(No.12zz069)Shanghai Municipal Natural Science Foundation,China(No.11ZR1400400)Fundamental Research Funds for the Central Universities,China(No.12D11303)
文摘A study was undertaken to investigate the production of amino acids from excess activated sludge (EAS) by enzymatic hydrolysis. Firstly, the protein was extracted from EAS. Secondly, the protein solution was further hydrolyzed under free enzyme or immobilized enzyme. The reversed phase high performance liquid chromatography (RP-HPLC) and inductively coupled plasma emission spectrometer (ICP) were applied to determine the contents of amino acids and heavy metals, respectively. The effects of enzyme/substrate(E/S), pH, temperature, and reaction time were investigated in detail. The results indicated that, the optimum conditions for protein hydrolysis were temperature 55℃, pH 10, E/S 9 g/L, and reaction time 8 h, and the highest yield of amino acids was more than 10 g/100 g dry sludge (DS) under free enzyme. Moreover, the security and nutrition were taken into consideration. There were seven kinds of essential amino acids and ten non-essential amino acids in the raw amino acid (RAA) solution, and the contents of heavy metals were lower, living up to Hygienical standard for feeds (China). This technology widens the source of amino acids and makes the extraction of amino acids from EAS more economic and effective.
基金supported by Ordu University Scientific Research Projects Coordination Unit(ODU/BAP)with project number BD-1701 and AR-1646.
文摘The recycling of waste from food processing is an important industrial procedure for obtaining protein sources with high added value.In this study,trout(Onchorynchus mykiss),anchovy(Engraulis encrasicolus),and whiting(Merlangius merlangus)wastes were hydrolyzed.The hydrolyzation procedure was investigated under the optimum predicted conditions defined by time,temperature,and enzyme ratio(E/S)using alkaline protease(pH 8),Protamex(pH 7),and Flavourzyme(pH 7).The hydrolysis conditions that showed the best degree of hydrolysis(DH%)were optimized using response surface methodology(RSM)with the central composite design(CCD)and Box-Behnken design(BBD)models.The effects of three independent variables,temperature(40-60℃),time(1-8 h),and enzyme concentrations(1-2%),were examined for model optimization.It was determined that the DH%varies between 50.92%and 74.30% according to the type of fish waste and enzyme.The highest degree of hydrolysis was observed from trout waste(74.30%)and the lowest degree from whiting waste(50.92%)with Flavourenzyme.From this study,it has been shown that different degrees of hydrolysis and protein recovery can be obtained,depending on fish species,waste composition,enzyme type,and hydrolysis method.
文摘为探究双酶不同酶解路线制得大米蛋白肽的性质差异,研究采用胰蛋白酶(A)和碱性蛋白酶(B)按不同酶解路线对大米蛋白进行酶解,制备了5种大米蛋白肽(A^(1)B^(1)、A^(1)B^(2)、A^(2)B^(1)、A^(1*)B^(2)、A^(2)B^(1*)),对其水解度、基本成分、氨基酸组成、微观结构、二级结构、分子量分布、风味和体外抗氧化活性等进行分析。结果表明,A^(2)B^(1)组的蛋白含量最高达到90.69%,肽含量高达72.73%;各路线的水解度大于17.60%,水解较为完全;微观结构均由不规则块状变为球体状,A1B2组和A^(1*)B^(2)组球体壁较厚,A^(2)B^(1)组和A^(2)B^(1*)组球体壁较薄,A^(1)B^(1)组为球体碎片;各路线的必需氨基酸含量比大米蛋白低,A1B2组必需氨基酸含量最高;二级结构以多种构象并存,各路线二级结构均以β-转角为主,占二级结构的44.62%~47.18%;各路线酶解产物多为低分子量的多肽,分子量低于5 k Da的多肽占92.09%~93.71%;A1B2样品鲜味最强,涩味最弱,A^(2)B^(1)样品咸味和苦味最弱;相比于A^(1)B^(1)组、A1B2组和A^(1*)B^(2)组,A^(2)B^(1)组和A^(2)B^(1*)组的抗氧化活性更强。通过对双酶不同酶解路线大米蛋白肽的性质研究,综合基本成分、肽含量、氨基酸组成、风味和抗氧化活性评价,A^(2)B^(1)组的品质最佳。
