title: Evaluation of the hydrolysis specificity of protease from marine Exiguobacterium sp. SWJS2 via free amino acid analysis.
abstract: This study evaluates the hydrolysis specificity of newly developed protease from Exiguobacterium sp. SWJS2 (EP) based on the released free amino acid (FAA) during enzymolysis and through comparing with commercially available papain and Alcalase 2.4L. Results showed that EP had great potential in producing hydrolysates with better nutrition and less bitterness. The percentages of essential amino acids in the EP-treated Coilia mystus and soybean protein were 72 and 70 %, respectively. And, corresponding hydrophobic amino acids were 74 and 72 %, respectively (i.e. <60 % for papain- or Alcalase 2.4L-treated samples). The differences in FAA releasing rates between EP and the two commercial proteases suggested that EP could become a new commercial protease that offers different reaction rates and extends protease application scope. Track changes in FAA profiles throughout EP hydrolysis revealed that the release of each amino acid exhibited its distinct regularity as the hydrolysis proceeded, which also varied with the substrate proteins. EP hydrolysis of C. mystus and soybean protein led to greater production rates of Phe, Leu, Val, Ile and Ala, suggesting that EP might have higher preference to these amino acids.
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou, 510640, China.
authors.forename: Fenfen
authors.initials: F
authors.lastname: Lei
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou, 510640, China.
authors.forename: Chun
authors.initials: C
authors.lastname: Cui
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou, 510640, China.
authors.forename: Qiangzhong
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou, 510640, China.|School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland, New Zealand.
authors.forename: Dongxiao
authors.initials: D
authors.lastname: Sun-Waterhouse
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou, 510640, China. femmzhao@scut.edu.cn.|State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, 510640, China. femmzhao@scut.edu.cn.
authors.forename: Mouming
authors.initials: M
authors.lastname: Zhao
mesh_terms: D059001:Aquatic Organisms / Q000201:enzymology*; D001419:Bacteria / Q000201:enzymology*; D001426:Bacterial Proteins / Q000737:chemistry*; D006868:Hydrolysis; D010447:Peptide Hydrolases / Q000737:chemistry*; D030262:Soybean Proteins / Q000737:chemistry; D013379:Substrate Specificity / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D030262:Soybean Proteins; D010447:Peptide Hydrolases