Unveiling the mechanism of fermentation induced antioxidant activity enhancement in asparagus juice: Metabolomic and transcriptomic insights into the functional role of Lactiplantibacillus plantarum JGS 49

Abstract

Fermentation has emerged as a pivotal strategy for improving the functional attributes of plant-based foods. This study demonstrates the biotransformation of asparagus juice through fermentation with Lactiplantibacillus plantarum JGS49, revealing systematic enhancements in nutritional and bioactive profiles. The process significantly elevated titratable acidity (1.56–10.26 g/L) and lactic acid content (10.29 g/L), while boosting total phenolic content and antioxidant capacity. Ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) analysis identified 1101 metabolites, with notable dynamic changes during fermentation. The fermentation process exhibited different substrate utilization patterns, characterized by the gradual consumption of small peptides, amino acids, nucleosides, and specific organic acids. The accumulation of characteristic bioactive metabolites was observed, among which metabolites such as phenylacetaldehyde, gentisic acid, 4-coumaric acid, homovanillic acid, indole-3-lactic acid, 3-phenyllactic acid, and DL-4-hydroxyphenyllactic acid became the signature biomarkers of the fermentation process. Transcriptome analysis disclosed substantial alterations in gene expression within L. plantarum JGS49 during fermentation, especially in the pathways related to translation and ribosomal function, peptide biosynthesis, and metabolic pathways. Differentially expressed genes were correlated with enriched metabolic pathways such as phenylalanine, tyrosine, and tryptophan biosynthesis, histidine metabolism, riboflavin metabolism, and glycerolipid metabolism in 0–12 h fermentation stage, while glycolysis/gluconeogenesis and pyruvate metabolism in 12–48 h fermentation stage. The integration of metabolomic and transcriptomic data clarified the mechanisms through which L. plantarum JGS49 enhances the nutritional quality and bioactivity of asparagus juice. This research laid a foundation for further exploration of L. plantarum-fermented asparagus juice as a functional food ingredient, emphasizing its potential to provide improved nutritional properties and health benefits.