Studies on Valorization of Dairy Waste for Probiotic & Nanobiotic Applications

Abstract

India, as one of the world’s largest dairy producers, generates approximately five million tons of paneer whey annually. This byproduct, rich in organic compounds, poses severe environmental challenges due to its high biochemical oxygen demand (BOD) and chemical oxygen demand (COD). Currently, a significant portion of whey is disposed of untreated into water bodies, contributing to pollution and ecological imbalance. While some whey is processed into animal feed or low-value products, these methods are limited and do not fully capitalize on whey’s potential for valorization, leading to persistent environmental concerns. This study addresses the need for sustainable whey valorization by transforming paneer whey into valuable bio-products. Leveraging Response Surface Methodology (RSM), we optimized the production of pediocin, an antimicrobial peptide, achieving a peak yield of 56,000 AU/ml. Our results show that the formulated whey medium produced five times more pediocin compared to conventional MRS (de Man–Rogosa–Sharpe) media, with significant validation through growth modeling. Encapsulation of Pediococcus pentosaceus in alginate enabled continuous pediocin production, effectively reducing Listeria monocytogenes by 4 log CFU during co-incubation, thus illustrating the medium's potential for enhanced microbial biomass and bioactive compound production. Furthermore, a Plant Growth-Promoting Bacteria (PGPB) consortium was developed from whey-cultivated Bacillus and Pseudomonas strains, which was tested in field trials on Bok choy plants. The consortium enhanced soil biodiversity, as shown by metagenomic analysis, which revealed increased bacterial richness and the emergence of new metabolic functions in treated soils. These results underscore the consortium’s potential to support sustainable agricultural practices by promoting plant growth and improving soil health.