Analysis of bioactive compounds in lyophilized aqueous extracts of barley sprouts

The objective of this study was to characterize the lyophilized aqueous extracts of barley variety Esmeralda and Perla ungerminated and germinated for 3, 5, and 7 days. Significant changes were observed in both barley varieties, particularly in the freeze-dried extracts of 7 days (P7, E7) compared to ungerminated barley extracts (P0, E0). There was an increase in the total content of carbohydrates, proteins, amino acids, and phenols. The freeze-dried extract P7 exhibited the highest content of total sugars, reducing sugars, and oligosaccharides, with values of 269.52, 23.95, and 853.8 mg/g dry weight (dw) respectively. The increase in protein and amino acid content was similar in P7 and E7. Additionally, a concentration of total phenols and flavonoids was observed to be 18.17 mg GAE/g and 2.54 mg QE/g in P7, and 21.73 mg and 2.8 mg QE/g in E7. Ferulic acid and catechin were the predominant compounds in all extracts. E7 showed a 327% increase in DPPH radical scavenging activity compared to ungerminated barley. On the other hand, in the ABTS assay, a 624% increase in antioxidant activity was observed in P5 extracts, and the capacity for Fe (II) ion oxidation increased by 134% in P7 extracts. These findings suggest that barley germination can enhance its nutrient profile and antioxidant capacity. The obtaining of aqueous extracts indicates the relevance for easy consumption, which has significant implications for human health, as barley-derived foods could provide additional health benefits or even the consumption of aqueous extracts as a base for a potential beverage.