Effect of ultrasound combined with exogenous GABA treatment on polyphenolic metabolites and antioxidant activity of mung bean during germination

•Ultrasound pretreatment enhanced the phenolics content of mung bean sprouts.•Phenolics content and antioxidant capacity of mung bean sprouts positively correlated.•A total number of 608 metabolites were detected in sprouted mung beans.•More than 50 phenolic compounds were identified in sprouts of mung bean.•Sprouted mung bean digest showed high phenolics content and antioxidant capacity.