Efficacy of Keratinolytic Bacteria (Bacillus pumilus) for decomposing non-sparingly degradable poultry feathers from waste to wealth

Abstract

There is a growing need for economical and environmentally responsible ways to valorizing poultry feather waste, and keratinolytic bacteria show significant promise. A single strain of Bacillus pumilus NM03, which was isolated from living poultry and has been shown to have substantial keratinolytic characteristics, degrades feathers. In this work, the effects of temperature on the quality of compost prepared with wheat and coriander straw were assessed both alone and in combination with thermophilic microbial inoculation. Temperature @ 37°C + inoculum significantly reduced total nitrogen loss (56.20 and 69.80%) and total organic carbon degradation (47.06 and 62.41%) in coriander and wheat straw composting, respectively, when compared to temperature @37°C. For different regression models, the higher and lower R2 values were estimated for the linear-linear and log logistic models for coriander with feather composting, and the linear-linear and linear models for wheat with feather composting, respectively. The principal component loading matrix obtained from correlation matrix reveals that the first three components whose eigen values are greater than 1, together account for about 91.70% and 87.69 % of the total explained variance in coriander and wheat with feather composting, respectively. Furthermore, our results showed that temperature @ 37°C + inoculum were most suited for feather composting with wheat and coriander straw for total organic carbon and total nitrogen breakdown was expedited for increased bacterial richness and diversity, as well as Bacillus pumilus overrepresentation. The quality of end-product obtained based on final C: N ratio coriander compost with feathers was found to be the best supplement for composting of such highly keratinoluytic waste.