Bioactivity of Cod and Chicken Protein Hydrolysates before and after in vitro Gastrointestinal Digestion.

Polona Jamnik,Tune Wulf,Ingrid Undeland,Annette Almgren,Hordur G Kristinsson,Margret Geirsdottir,Katja Istenič, ,Tatjana Koštomaj,Rosa Jonsdottir

doi:10.17113/ftb.55.03.17.5117

Abstract

Bioactivity of cod (Gadus morhua) and chicken (Gallus domesticus) protein hydrolysates before and after in vitro gastrointestinal (GI) digestion was investigated using yeast Saccharomyces cerevisiae as a model organism. Both hydrolysates were exposed to in vitro GI digestion prior to cellular exposure to simulate digestion conditions in the human body and therefore investigate the role of modulations in the GI tract on the cell response. The effect of digested and undigested hydrolysates on intracellular oxidation, cellular metabolic energy and proteome level was investigated. No difference in the effect on intracellular oxidation activity was obtained between cod and chicken hydrolysates, while higher affect on intracellular oxidation was provided by digested hydrolysates, with relative values of intracellular oxidation of cod of (70.2±0.8) and chicken of (74.5±1.4) % than by undigested ones, where values of cod and chicken were (95.5±1.2) and (90.5±0.7) %, respectively. Neither species nor digestion had any effect on cellular metabolic energy. At proteome level, digested hydrolysates gave again significantly stronger responses than undigested counterparts; cod peptides here also gave somewhat stronger response than chicken peptides. The knowledge of the action of food protein hydrolysates and their digests within live cells, also at proteome level, is important for further validation of their activity in higher eukaryotes to develop new functional food ingredients, such as in this case chicken and cod muscle-derived peptides.

Highlights

Protein hydrolysates containing bioactive peptides show potential use as functional food ingredients for health promotion and disease risk reduction
Proteome changes after exposing yeast cells to non-digested and digested cod and chicken protein hydrolysates To study the effects of protein hydrolysates, before and after gastrointestinal digestion (GI) digestion, at a proteome level, the protein profile of yeast cells treated with both, non-digested and digested protein hydrolysates was analyzed
In the cells exposed to non-digested and digested chicken or cod protein hydrolysates, yeast proteins down-regulated by hydrolysates were identified as peptidyl-prolyl cis-trans isomerase (PPIase), elongation factor 1-beta (Efb1), elongation factor 2 (Eft2), translationally-controlled tumor protein homolog (Tma19), peroxiredoxin (Tsa1) and cytochrome c oxidase subunit 6 (Cox6) (Table 2, Fig. 3)

Summary

Introduction

Protein hydrolysates containing bioactive peptides show potential use as functional food ingredients for health promotion and disease risk reduction. This study beside proteome investigated the effects of cod and chicken protein hydrolysates on antioxidant activity and cellular metabolic energy using yeast S. cerevisiae in the stationary phase as a model organism, where yeast cells resemble cells of multicellular organisms in important aspects (most energy comes from mitochondrial respiration, G0 phase, oxidative damages accumulate over time) [4] Both hydrolysates were exposed to in vitro GI digestion prior to cellular exposure to simulate the digestion conditions in the human body and investigate the role of enzymatic breakdown and other modulations in the GI tract on the responses given by the peptides. For both cod and chicken, such simulated digestion studies with treatment of cells with digests have not been reported earlier

Methods

Results

Conclusion