微生物法生产γ-聚谷氨酸工艺优化及其在农业领域的应用研究进展

Optimization of microbial production process of γ-polyglutamic acid and research progress in its application in agriculture

摘要:

我国农业目前正朝着集约化、信息化、智慧化、绿色化方向发展，人们对农产品的选择更注重安全、绿色和生态健康。因此，化肥安全性、低残留和环保性显得尤为重要。天然生物发酵的生物刺激素因绿色环保、安全有效，能够减肥增效而受到广泛关注。其中，γ-聚谷氨酸(γ-polyglutamic acid, γ-PGA)是一种由微生物合成的聚氨基酸，具有无毒、可食用、保湿、易螯合、易分散等特点，广泛应用于医疗、食品和农业领域，是一种理想的新型生物刺激素肥料。本文对γ-PGA的合成途径与条件、工艺优化以及应用等方面的研究进展进行了综述，包括微生物(芽孢杆菌)发酵制备γ-PGA的流程、培养基营养成分的发酵工艺优化等。另外，本文还讨论了农用γ-PGA分析测定的不同方法以及γ-PGA在土壤改良、肥料增效、作物生长调节等方面的应用效果，为γ-PGA的微生物发酵合成提供了参考，并为其在农业新型肥料领域的进一步发展提供了新的思路。

Abstract:

China’s agriculture is progressing towards more intensive, information-driven, smart, and environmentally friendly practices. Consumers are increasingly prioritizing safety, sustainability, and ecological health when selecting agricultural products. Accordingly, the safety, low residue, and environmental friendliness of chemical fertilizers have become crucial. Biostimulants derived from natural fermentation have attracted considerable attention due to their eco-friendly nature, safety, efficacy, and ability to reduce fertilizer application while enhancing efficiency. Among these, γ-polyglutamic acid (γ-PGA), a microbially synthesized polyamino acid, is non-toxic, edible, moisturizing, readily chelatable, and highly dispersible. It is extensively used in the medical, food, and agricultural sectors, making it an ideal novel biofertilizer and biostimulant. This review summarizes the latest research on biosynthetic pathways, production conditions, process optimization, and applications of γ-PGA. This review provides an overview and analysis of the fermentation process for γ-PGA production by Bacillus strains, with a focus on optimizing the medium composition. Furthermore, this article discusses various analytical methods for quantifying γ-PGA in agricultural applications and examines its effects on soil improvement, fertilizer efficiency enhancement, and crop growth regulation. This review aims to provide valuable insights into the microbial synthesis of γ-PGA and propose new directions for its development in the field of new fertilizers.