Bioactivity surveys of some medicinal plants in Trat Agroforestry Research and Training Station, Trat Province

This study investigates the bioactivity properties of 16 ethanolic extracts from medicinal plants, representing 8 families, collected from the Trat Agroforestry Research and Training Station in Trat province. The research specifically examines three bioactivity properties: antioxidant activity, anti-diabetic activity and anti-inflammatory activity. Antioxidant activity was evaluated using DPPH, FRAP, ABTS and nitric oxide scavenging assays. The anti-diabetic activity was determined by inhibiting alpha-glucosidase and alpha-amylase, while the anti-inflammatory activity was assessed by inhibiting BSA denaturation. The findings indicate that Volkameria inermis exhibited the highest antioxidant potential, as measured by DPPH (IC50 = 0.011 ± 0.005 mg/mL), ABTS (IC50 = 57.173 ± 6.901 mg/mL), FRAP (IC50 = 0.070 ± 0.020 mg/mL) and nitric oxide scavenging (IC50 = 0.127 ± 0.071 mg/mL) and was characterized by a significant phenolic compound content (121.92 ± 0.66 mg GAE/g). Moreover, extracts from the Garcinia family, specifically Garcinia cowa and Garcinia hanburyi, demonstrated notable anti-diabetic properties, inhibiting alpha-glucosidase (IC50 = 1.383 ± 0.131 mg/mL) and alpha-amylase (IC50 = 0.233 ± 0.012 mg/mL), respectively. Notably, Gnetum gnemon was the only plant to exhibit substantial anti-inflammatory activity (IC50 = 0.034 ± 0.011 mg/mL) through its capacity to protect bovine serum albumin (BSA) from degradation. Consequently, further research is warranted to identify the key substances and mechanisms of action that contribute to the development of effective therapeutic agents and medicinal applications

New insights into the evolutionary history of plant sorbitol dehydrogenase

Background: Sorbitol dehydrogenase (SDH, EC 1.1.1.14) is the key enzyme involved in sorbitol metabolism in higher plants. SDH genes in some Rosaceae species could be divided into two groups. L-idonate-5-dehydrogenase (LIDH, EC 1.1.1.264) is involved in tartaric acid (TA) synthesis in Vitis vinifera and is highly homologous to plant SDHs. Despite efforts to understand the biological functions of plant SDH, the evolutionary history of plant SDH genes and their phylogenetic relationship with the V. vinifera LIDH gene have not been characterized. Results A total of 92 SDH genes were identified from 42 angiosperm species. SDH genes have been highly duplicated within the Rosaceae family while monocot, Brassicaceae and most Asterid species exhibit singleton SDH genes. Core Eudicot SDHs have diverged into two phylogenetic lineages, now classified as SDH Class I and SDH Class II. V. vinifera LIDH was identified as a Class II SDH. Tandem duplication played a dominant role in the expansion of plant SDH family and Class II SDH genes were positioned in tandem with Class I SDH genes in several plant genomes. Protein modelling analyses of V. vinifera SDHs revealed 19 putative active site residues, three of which exhibited amino acid substitutions between Class I and Class II SDHs and were influenced by positive natural selection in the SDH Class II lineage. Gene expression analyses also demonstrated a clear transcriptional divergence between Class I and Class II SDH genes in V. vinifera and Citrus sinensis (orange). Conclusions Phylogenetic, natural selection and synteny analyses provided strong support for the emergence of SDH Class II by positive natural selection after tandem duplication in the common ancestor of core Eudicot plants. The substitutions of three putative active site residues might be responsible for the unique enzyme activity of V. vinifera LIDH, which belongs to SDH Class II and represents a novel function of SDH in V. vinifera that may be true also of other Class II SDHs. Gene expression analyses also supported the divergence of SDH Class II at the expression level. This study will facilitate future research into understanding the biological functions of plant SDHs.Other UBCReviewedFacult