Elevation of gamma-aminobutyric acid (GABA) and essential amino acids in vacuum impregnation mediated germinated rice traced by MALDI imaging

Optimization of germination and ultrasonic‐assisted extraction for the enhancement of γ‐aminobutyric acid in pumpkin seed

“…In addition, the AA content of XC‐2 was significantly higher than other cultivars. The enhancement of essential amino acid contents was observed in a previous study of germinated rice (Kamjijam et al., 2021 ), which is consistent with the results in this study. Combined with the results of protein content, we conclude that part of macromolecular protein is converted into amino acids during germination (Guo et al., 2011 ).…”

“…And the lack of fit value was found to be not significant ( p = .41 > .05), which proved the validity of the experimental model. The analysis of variance (ANOVA) showed that GABA content was significantly ( p < .05) affected by MSG concentration and germination time, being the effect of germination time higher than MSG concentration, and the result was consistent with the germination study on rice (Kamjijam et al., 2021 ). Additionally, germination time and MSG concentration interacted significantly on GABA accumulation during germination.…”

Unravel the Local Complexity of Biological Environments by MALDI Mass Spectrometry Imaging

“…GABA was shown to increase constantly and reached a maximum after 96 h. In the white rice variety, most amino acids (e.g., glutamic acid, alanine, arginine, asparagine, aspartic acid, cysteine, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline serine, threonine, tryptophan, tyrosine, and valine) accumulated in the scutellum, the coleoptile, and the aleurone layer but were absent from the endosperm. Except for tryptophan, methionine, and aspartic acid, most of them were found in the endosperm in the brown rice variety [52].…”

Identification of Markers of Saccharides in Polygonati Rhizoma During the Steaming Process by MALDI-TOF Mass Spectrometry Imaging

“…With little or no sample pretreatment, various natural compounds could be simultaneously detected in a single run, providing the spatial information of chemicals within samples in studies. These included hard and dry cereals [16] , coffee beans [17] ， chocolates [18] , corn stalks [19] , peptide in dry-cured ham muscle fibers [20] ,and polyphenols and related primary metabolites in bilberry [21] .Other reported samples included gamma-aminobutyric acid and essential amino acids in vacuum impregnation mediated germinated rice [22] ,curcumin analogs in dried turmeric root [23] , specialized metabolites in tea [24] ,and metabolites at different maturity stages of strawberry [25] .Further, the distribution and changes of glycoalkaloids in potato tubers under different storage duration [26] and phytochemicals in the dried root of Isatis indigotica [27] were also reported. To date, to the best of our knowledge, there is no report yet on mapping phytochemicals in Polygonati rhizoma using MSI to investigate the accumulation patterns of nutrient types in this medicinal herb and food.…”