Potential of coumarins against Covid-19.

Isolation of two new phenolic C-glucosides and in silico LSD1 and quorum sensing inhibitory potential of phytoconstituents isolated from Ardisia elliptica Thunb aerial parts.

Faidherbia albida is one of the plants that have been used traditionally throughout the world in the treatment of diabetes. In previous studies, various parts of the plant such as the methanolic root bark, aqueous seed and the aqueous stem bark extracts have been tested on alloxan induced diabetic rats for their anti-hyperglycemic activity. In the current study, the anti-hyperglycemic activity of total ethanolic extract of F. albida fruits was evaluated in nicotinamide-streptozotocin induced diabetic mice using glimepiride as a reference anti-diabetic drug. Total ethanolic fruit extract at 200mg/kg body weight significantly (p < 0.05) lowered the blood glucose levels of diabetic mice by (74%) within 4 hours of oral administration while the peak of the hypoglycemic effect of glimepiride (55.2%) occurred at 4th hour after oral administration. The results provided evidence that F. albida fruit extract is recommended to be used as a hypoglycemic drug in treating diabetes patients.

Genus Acacia (Mill.), with approximately 1300 species, is considered the largest genus in family Fabaceae. It has been used traditionally throughout the world in the treatment of different types of cancer. In the course of the search for selective cytotoxic substance on the human pancreatic carcinoma PANC-1 cells adapted to nutrient starvation, two known lupane-type triterpenes; 3β-O-cis-coumaroylbetulinic acid (1), and betulinic acid (2) and one steroid compound; stigmasterol (3) were isolated for the first time from the extract of Acacia laeta R. Br. ex Benth (Fabaceae) stem. The chemical structures of compounds 1-3 were determined using spectroscopic analysis. Cytotoxic activities of the isolated compounds against PANC-1 adapted to glucose deficiency were determined Both compounds 1 and 2 showed selective inhibition of the growth of PANC-1 cells under glucose deficient conditions, with IC50 values of 3.3 and 5.0 μM, respectively, whereas compound 3 did not show the activity up to 100 µM.

Discovering alternative compounds for treating antibiotic-resistant infections is critical to alleviate the current antibiotic resistance crisis. Endophytic fungi are a source of numerous recently approved antibiotics particularly polyketide-derived molecules. This study aimed to isolate and identify antimicrobial compounds from Dothideomycetes sp. 11144 as well as molecular docking study for their affinity to different Methicillin-resistant Staphylococcus aureus (MRSA) selected proteins. Herein, we describe the isolation of four polyketide-type metabolites, a new natural α-pyrone derivative, (R)-6-(2-hydroxypropyl)-4-methoxy-2H-pyran-2-one (1) along with three known anthraquinone derivatives, chrysophanol (2), emodin (3), and coniothyrinone B (4) from Dothideomycetes sp. 11144 liquid culture. The extracts and isolated compounds were screened for their antimicrobial activity. (R)-6-(2-hydroxypropyl)-4-methoxy-2H-pyran-2-one (1) and emodin (3) exhibited antibacterial activity against MRSA with IC50 values of 61.0 and 24.4 µM, respectively. They were screened virtually via molecular docking for their affinity to different MRSA essential proteins compared to conventional inhibitors. Emodin demonstrated high affinity to the penicillin-binding protein with a pose score of -13.57 kcal/mol (1MWT). The emodin architecture could serve as a framework for the development of potent anti-MRSA antibiotics.