Improvement of antioxidant potential in rats consuming feathers protein hydrolysate obtained by fermentation of the keratinolytic bacterium, Bacillus pumilus A1

Abstract

The in vitro and in vivo antioxidant activities of feathers protein hydrolysate (FPH), produced by fermentation with the keratinolytic bacterium, Bacillus pumilus strain A1, were evaluated. The antioxidant activities of FPH, evaluated using DNA nicking and ferrozine assays, demonstrate that FPH present an important antioxidant potential. Interestingly, the addition of this hydrolysate (2.5 and 5%) to the feed of rats caused a significant decrease in the rate of thiobarbutiric acid reagent substances (TBARS) and the enzymatic antioxidants activities (superoxide dismutase, glutathione peroxidase and catalase) in liver, kidney, heart, brain and cerebella, as compared to the control. However, the supplementation of the standard food by 2.5% of untreated feather meal or 5% of soya is associated with an increase of the TBARS rate and enzymatic antioxidant activities. These results indicate that FPH may be useful as supplementary proteins and natural antioxidant in animal feed formulation.

Key words: Feather protein hydrolysate, Bacillus pumilus, lipids peroxidation, oxidative stress, dietary ingredient.