title: Antioxidant Effect and Functional Properties of Hydrolysates Derived from Egg-White Protein.
abstract: This study utilized commercially available proteolytic enzymes to prepare egg-white protein hydrolysates (EPHs) with different degrees of hydrolysis. The antioxidant effect and functionalities of the resultant products were then investigated. Treatment with Neutrase yielded the most α-amino groups (6.52 mg/mL). Alcalase, Flavourzyme, Protamex, and Ficin showed similar degrees of α-amino group liberation (3.19-3.62 mg/mL). Neutrase treatment also resulted in the highest degree of hydrolysis (23.4%). Alcalase and Ficin treatment resulted in similar degrees of hydrolysis. All hydrolysates, except for the Flavourzyme hydrolysate, had greater radical scavenging activity than the control. The Neutrase hydrolysate showed the highest 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity (IC50=3.6mg/mL). Therefore, Neutrase was identified as the optimal enzyme for hydrolyzing egg-white protein to yield antioxidant peptides. During Neutrase hydrolysis, the reaction rate was rapid over the first 4 h, and then subsequently declined. The IC50 value was lowest after the first hour (2.99 mg/mL). The emulsifying activity index (EAI) of EPH treated with Neutrase decreased, as the pH decreased. The EPH foaming capacity was maximal at pH 3.6, and decreased at an alkaline pH. Digestion resulted in significantly higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ABTS radical scavenging activity. The active peptides released from egg-white protein showed antioxidative activities on ABTS and DHHP radical. Thus, this approach may be useful for the preparation of potent antioxidant products.
authors.affiliation: Comimax Co. Ltd., Seoul 139-860, Korea.
authors.forename: Dae-Yeon
authors.initials: DY
authors.lastname: Cho
authors.affiliation: Department of Food and Nutrition, Korea University, Seoul 136-703, Korea.
authors.forename: Kyungae
authors.initials: K
authors.lastname: Jo
authors.affiliation: Department of Food and Nutrition, Korea University, Seoul 136-703, Korea.
authors.forename: So Young
authors.initials: SY
authors.lastname: Cho
authors.affiliation: Department of Food Science and Biotechnology of Animal Resources, Konkuk University, Seoul 143-701, Korea.
authors.forename: Jin Man
authors.initials: JM
authors.lastname: Kim
authors.affiliation: Dairy Food R&D Center, Maeil Dairies Co., Ltd. Pyungtaek 451-861, Korea.
authors.forename: Kwangsei
authors.initials: K
authors.lastname: Lim
authors.affiliation: Department of Food and Nutrition, Korea University, Seoul 136-703, Korea; BK21PLUS Program in Embodiment: Health-Society Interaction, Department of Public Health Science, Graduate School, Korea University, Seoul 136-703, Korea.
authors.forename: Hyung Joo
authors.initials: HJ
authors.lastname: Suh
authors.affiliation: Division of Animal Science, Chonnam National University, Gwangju 500-757, Korea.
authors.forename: Sejong
authors.initials: S
authors.lastname: Oh
keywords: Neutrase; egg-white protein; functionality; hydrolysate; radical scavenging activity