Therapeutic Potential of Diospyros malabarica Methanolic Leaf Extract: Evidence of Anticancer, Antimicrobial, Antisickling, and Sedative Effects

Abstract

Diospyros malabarica, more commonly referred to as the Gaub tree, is known for its ethnomedicine applications, though there is inadequate research regarding its physical capabilities. Herein is described the full study investigating the anticancer, antimicrobial, antisickling and neuropharmacological activities of a methanol extract of D. malabarica leaves (MEDM). MEDM was prepared by cold maceration and subjected to standardised bioassays. MEDM showed considerable anticancer activity with a clear dose-dependent effect against the cervical cancer cell line HeLa, inhibiting cell growth by 49.16 (1000 µg/mL), in conjunction with unequivocal morphological evidence of apoptosis. In a disc diffusion test of antimicrobial properties, MEDM showed broad-spectrum activity against Gram-positive (Bacillus cereus and Staphylococcus aureus) and Gram-negative bacteria (Vibrio cholerae and Klebsiella pneumoniae), as well as several fungi, and inhibition zones increased in a concentration-dependent manner. Cells were placed in 24-well plates and treated with DMSO or extract at the IC50 concentration for 24 hours. The experimental data were replicated three times, and the mean and standard deviation were used to represent the results. Excel is commonly utilised for conducting statistical analyses. A unique and notable finding was the validated potent antisickling activity where MEDM (500 µg/mL) reversed sickled red blood cells by 72.49% after 120 minutes and was found to be superior to the standard drug phenylalanine at several different time points. The neuropharmacological study suggested obvious effects, and in the sleep test with thiopental sodium, 400 mg/kg of MEDM significantly reduced the time to sleep and increased time asleep. Also, in the forced swimming test, MEDM significantly increased immobility time in a dose-dependent manner, suggesting a sedative effect. The findings clearly show that Diospyros malabarica has a range of therapeutic effects. The bioactivities seen are probably due to its unique and abundant phytochemical profile characterised by flavonoids, tannins, and terpenoids, which are known to induce effects such as apoptosis, disrupt microbial membranes, block haemoglobin S polymerisation and influence GABAergic neurotransmission. This work provides solid science to bolster the traditional uses of D. malabarica. These findings suggest a potential avenue for discovering future therapeutics for cancer, sickle cell disease, microbial infections, and/or neurological disorders. Future work should focus on the isolation and identification of bioactive compounds responsible for each activity in order to more accurately define the mechanisms of action, as well as other possible uses in the clinic.