Separation and identification of microbial enzymes on cereal grains/oilseeds and their activity assessment and effects on the quality of processing products - A comprehensive review

Abstract

Grains/oilseeds and their processing by-products are readily colonized by a diverse and complex microbial community. This microbial community actively interacts with plants by secreting various metabolites through every process, from seed to maturation, harvesting, processing and storage. It is a major driver in the spoilage of final products and bulk storage feedstocks such as wheat, corn, and legumes. Recent studies indicate that enzymes secreted by microbes significantly impact the quality of grains/oilseeds, as well as their subsequent processing products. Current analytical studies on microbial enzymes associated with grains/oilseed surfaces primarily focus on specific species. Seeds in fields or storage are exposed to dynamic and diverse microbial communities, leading to uncertainties in microbial protein sources and inaccuracies in protein identification. This hinders our ability to develop targeted preventive measures against microbial damage. Moreover, the regularity of distribution and the activity assessment of these microbial enzymes will also affect the decision-making for final preventive measures. Consequently, it is of great significance to evaluate the hydrolytic activities of the enzymes and identify the species and sources of relevant enzymes in attack, invasion, and colonization. This review provides a comprehensive overview of the impact of microbial origin enzymes on grain/oilseed and their proteomic analysis strategies, as well as the limitations and challenges in the current methods.