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Mung bean starch is distinguished by its exceptional high amylose content and regulation of starch biosynthesis in leaves and storage tissues, such as seeds, share considerable similarities. Genetic engineering of starch composition and content, requires detailed knowledge of starch biosynthetic gene expression and enzymatic regulation. In this study we applied detailed transcriptomic analyses to unravel the global differential gene expression patterns in mung bean leaves and in seeds during various stages of development. The objective was to identify candidate genes and regulatory mechanisms that may enable generation of desirable seed qualities through the use of genetic engineering. Notable differences in gene expression, in particular low expression of the Protein Targeting to Starch (PTST), starch synthase (SS) 3, and starch branching enzyme1 (SBE1) encoding genes in developing seeds as compared to leaves were evident. These differences were related to starch molecular structures and granule morphologies. Specifically, the starch molecular size distribution at different stages of seed development correlated with the starch biosynthesis gene expression of the SBE1, SS1, granule-bound starch synthases (GBSS) and isoamylase 1 (ISA1) encoding genes. Furthermore, putative hormonal and redox controlled regulation were observed, which may be explained by abscisic acid (ABA) and indole-3-acetic acid (IAA) induced signal transduction, and redox regulation of ferredoxins and thioredoxins, respectively. The morphology of starch granules in leaves and developing seeds were clearly distinguishable and could be correlated to differential expression of SS1. Here, we present a first comprehensive transcriptomic dataset of developing mung bean seeds, and combined these findings may enable generation of genetic engineering strategies of for example starch biosynthetic genes for increasing starch levels in seeds and constitute a valuable toolkit for improving mung bean seed quality.

A cytological study was carried out on four Zingiber species from Thailand, namely, Z. chrysostachys, Z. isanense, Z. junceum, and Z. niveum, which are edible and beautiful ornamental plants. They all have somatic chromosomal numbers of 2n = 22. This research contributes to karyological knowledge regarding this species. The somatic chromosomal counts of Z. niveum and Z. isanense are reported for the first time, as are the NFs of all species, which were all discovered to be 44. All four edible and ornamental species had their karyotypes: 16m + 6sm for Z. chrysostachys, 4m + 18sm for Z. isanense, 12m + 10sm for Z. junceum, and 14m + 4sm + 4st for Z. niveum. The dominant characteristics of these four Zingiber species are as follows: Z. chrysostachys has yellow bracts, pale yellow flowers, and a red labellum with white dots; Z. isanensis has red-brown bracts, white flowers, and a white labellum; Z. junceum has green bracts, yellow flowers, and a yellow labellum; and Z. niveum has white bracts, yellow flowers, and a yellow labellum. Additionally, principal component analysis (PCA) of the karyotype formula was used to divide the four Zingiber species into two groups via various points using the chromosome indexes (CIs): Z. niveum (D) with Z. chrysostachys (A), and Z. junceum (C) with Z. isanensis (B). This finding implies that, while being in the same stage, the CIs of these four Zingiber species can be used to distinguish them, revealing their resemblance at unique stages and close relationship. Accordingly, the chromosomal structure, karyotype formulae, and CIs can be used to distinguish these four edibles and ornamental Zingiber species from Thailand.

Mulberry fruits are used for food, cosmetics and medicine. Several phytochemical and bioactive compounds in mulberry fruits are widely used for health benefits. During the ripening stage of mulberry fruits, different phytochemicals are present. This study investigates color, phytochemical compounds and antioxidant activity in mulberry fruit during seven ripening stages. The results indicate that the color changes from green to purple. The green stage contains high levels of vitamin c (12 mg/gDW), while the purple stage has the highest sugar levels, particularly fructose (241 mg/gDW) and glucose (171 mg/gDW). Trends of amino acids, anthocyanin and vitamin C increased initially, peaking in M6 and then declined in the final ripening stage (M7). Phenolic acid, flavonoids and γ-aminobutyric increased when the ripening level increased. The antioxidants activity was analyzed by 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) free radical and ferric reducing antioxidant power (FRAP) assays. It was found to have the highest contents in M7 at 19 mgTE/gDW (DPPH) and 22 mg FeSO4/gDW (FRAP), which were positively correlated with the total phenolic and total flavonoid contents. This study provides information on mulberry fruit during ripening that should be helpful in designing products while maintaining its high antioxidant content, excellent bioactivity and quality for use in food, cosmetics and medicine.