Background: The increasing environmental impact of food waste, especially starch-rich residues, necessitates sustainable biodegradation methods to reduce pollution and resource wastage. Objectives: This study aimed to isolate α-amylase-producing bacteria from saline-rich organic soils in Jeddah, Saudi Arabia, and assess their effectiveness in degrading food waste through enzymatic starch hydrolysis. Materials and Methods: A16, was identified using biochemical assays (Gram staining, catalase/oxidase tests) and 16S rRNA sequencing. Enzyme production was optimized at different pH levels (4-9) and temperatures (30-60 °C). Purification involved ammonium sulfate precipitation (80% saturation), dialysis, and chromatography (Sephadex G-100, DEAE-Sephadex A-50). The purified enzyme was applied to 10 kg of food waste (bread and fruits) to evaluate degradation efficiency. Results: ). Purification resulted in a 58 kDa enzyme with a 3.7-fold increase in specific activity (5.448 U.mg-1). Food waste treated with AK16 showed a 50% volume reduction within 25 days, accompanied by rapid starch decomposition. Conclusions: A16 as a highly effective and environmentally friendly biocatalyst for the degradation of starch-rich waste. Its excellent alkaline and thermal stability, along with its ability to efficiently reduce waste, demonstrate its potential for sustainable use in industrial and environmental settings. These results present a promising bio-based approach to managing organic waste, promoting a circular economy, and minimizing the environmental impact of waste disposal.
Khalel et al. (Wed,) studied this question.