Araçain, a tyrosol derivative and other phytochemicals from Psidium guineense Sw

DNA Barcode, chemical analysis, and antioxidant activity of Psidium guineense from Ecuador

This study investigates the phytochemical, genetic, and antioxidant properties of Psidium guineense, a species native to the tropical dry forests of Ecuador. Leaves were collected, preserved in recognized herbaria, and subjected to Soxhlet extraction using polar and non-polar solvents. Phytochemical screening revealed the presence of secondary metabolites, while GC-MS analysis detected chemical compounds in the extracts. Antioxidant assays demonstrated high phenolic (54.34 ± 0.49 mg GAE/g) and flavonoid (6.43 ± 0.38 mg QE/g) content, with significant antioxidant activity in DPPH (0.57 ± 0.04 mg TE/g), FRAP (105.52 ± 6.85), and ABTS (1.25 ± 0.01 mg TE/g) assays. DNA barcoding of nine loci, (seven from the chloroplast genome and two nuclear genome) using a CTAB extraction protocol and PCR, provides the first genetic characterization of this species, contributing to genetic diversity assessments and phylogenetic studies. These findings underscore the importance of P. guineense as a source of potent bioactive compounds with significant antioxidant potential, highlighting its applicability in nutritional and pharmaceutical industries. Additionally, the genetic insights gained support efforts to expand DNA barcoding databases for tropical biodiversity conservation.

A novel Vestitain A from the ripe fruits of Embelia vestita Roxb

A new compound, vestitain A (1), together with 11 known compounds were isolated from the ripe fruits of Embelia vestita Roxb., among them compounds 5,10-12 were isolated from this plant for the first time. Their structures were elucidated and characterized by detailed spectroscopic analysis. Further, the isolated new compound 1 was evaluated for its hypoglycemic effects in vivo. Our research showed that compound 1 could decrease the fasting blood glucose (FBG) by approximately 36.31% in diabetic rats at the high dose (800 mg/kg). By the Morris Water Maze experiments, we found that compound 1 had the effect of intervention on social behavior in diabetic rats, which might provide a reference basis for its development and utilization as a potential hypoglycemic drug.

The antibacterial activity of natural-derived flavonoids

Flavonoids, a wide variety of phenolic secondary metabolites, are found in almost all plant families in the leaves, stems, roots, flowers, and seeds. Flavonoids could exert antibacterial activity via damaging the cytoplasmic membrane, inhibiting energy metabolism, and inhibiting the synthesis of nucleic acids, so flavonoids are considered constitutive antibacterial substances. This review aims to outline the recent advances of natural-derived flavonoids, including flavonoid glycosides with antibacterial potential to provide novel antibacterial lead hits/candidates, covering articles published between January 2016 and July 2021.

First complete NMR data and theoretical study of an antimicrobial formylated dihydrochalcone from Psidium guineense Sw

Chalcones are a widespread group of natural compounds characterized by the basic structure 1,3-diaryl-2-propen-1-one. In this study, we focused on the uncommon formylated chalcone 3'-formyl-2',4',6'-trihydroxy-5'-methyldihydrochalcone that possess interesting antimicrobial and anticancer potential. Considering the pharmacological relevance of this compound, we report its isolation and the first complete and unequivocal NMR data for this substance, corroborated by in silico theoretical study. In addition to that, its antibacterial potential was evaluated and the compound presented strong activity against Pseudomonas aeruginosa.[Formula: see text].