Comparison of antioxidant activities of bovine whey proteins before and after simulated gastrointestinal digestion |
| |
Authors: | Alberto R. Corrochano Yunus Sariçay Elena Arranz Phil M. Kelly Vitaly Buckin Linda Giblin |
| |
Affiliation: | 1. Teagasc Food Research Centre, Moorepark, Fermoy, Co Cork, Ireland, P61 C996;2. School of Chemistry & Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland, D04 V1W8 |
| |
Abstract: | Oxidative stress caused by free radicals has been implicated in several human disorders. Dietary antioxidants can help the body to counteract those reactive species and reduce oxidative stress. Antioxidant activity is one of the multiple health-promoting attributes assigned to bovine whey products. The present study investigated whether this activity was retained during upper gut transit using a static simulated in vitro gastrointestinal digestion (SGID) model. The capacity to scavenge free radicals and reduce ferric ion of whey protein isolate (WPI), individual whey proteins, and hydrolysates pre- and post-SGID were measured and compared using various antioxidant assays. In addition, the free AA released from individual protein fractions in physiological gut conditions were characterized. Our results indicated that the antioxidant activity of WPI after exposure to the harsh conditions of the upper gut significantly increased compared with intact WPI. From an antioxidant bioactivity viewpoint, this exposure negates the need for prior hydrolysis of WPI. The whey protein α-lactalbumin showed the highest antioxidant properties post-SGID (oxygen radical absorbance capacity = 1,825.94 ± 50.21 μmol of Trolox equivalents/g of powder) of the 4 major whey proteins tested with the release of the highest amount of the antioxidant AA tryptophan, 6.955 μmol of tryptophan/g of protein. Therefore, α-lactalbumin should be the preferred whey protein in food formulations to boost antioxidant defenses. |
| |
Keywords: | whey protein hydrolysis antioxidant activity simulated gastrointestinal digestion α-lactalbumin |
本文献已被 ScienceDirect 等数据库收录! |
|