Search

Acacia nilotica ( A. nilotica) is an important medicinal plant, found in Africa, the Middle East, and the Indian subcontinent. Every part of the plant possesses a wide array of biologically active and therapeutically important compounds. We reported the antileishmanial activity of A. nilotica bark methanolic extract through in vitro antileishmanial assays and dissected the mechanism of its action through in silico studies. Bark methanolic extract exhibited antipromastigote and antiamastigote potential in a time and dose-dependent manner with IC 50 values of 19.6 ± 0.9037 and 77.52 ± 5.167 μg/mL, respectively. It showed cytotoxicity on THP-1-derived human macrophages at very high dose with a CC 50 value of 432.7 ± 7.71 μg/mL. The major constituents identified by gas chromatography-mass spectrometry (GC-MS) analysis, 13-docosenoic acid, lupeol, 9,12-octadecadienoic acid, and 6-octadecanoic acid, showed effective binding with the potential drug targets of Leishmania donovani ( L. donovani ) including sterol 24- c -methyltransferase, trypanothione reductase, pteridine reductase, and adenine phosphoribosyltransferase, suggesting the possible mechanism of its antileishmanial action. Pharmacokinetic studies on major phytoconstituents analyzed by GC-MS supported their use as safe antileishmanial drug candidates. This study proved the antileishmanial potential of bark methanolic extract A. nilotica and its mechanism of action through the inhibition of potential drug targets of L. donovani ., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Cassia fistula has a wide array of biologically active and therapeutically important class of compounds. Leishmania donovani important drug targets, sterol 24-c methyltransferase ( Ld SMT), trypanothione reductase ( Ld TR), pteridine reductase ( Ld PTR1), and nucleoside hydrolase ( Ld NH), were modelled, and molecular docking was performed against the abundant phytochemicals of its leaf extract. Molecular docking results provided the significant prima facie evidence of the leaf extract to have antileishmanial potential. To confirm this, we performed in vitro antileishmanial and cytotoxicity assays. Methanolic extract of C. fistula leaves showed growth inhibition and proliferation of L. donovani promastigote with an IC 50 value of 43.31 ± 4.202 μg/mL. It also inhibited the growth of intra-macrophagic amastigotes with an IC 50 value of 80.76 ± 3.626 μg/mL. C. fistula extract was found cytotoxic at a very high concentration on human macrophages (CC 50 = 626 ± 39 μg/mL). Annexin V/propidium iodide (PI) staining assay suggested partial apoptosis induction in parasites by C. fistula to exert its antileishmanial activity. Here, for the first time, we have shown the antileishmanial potential of C. fistula leaves. Overall, our results could open new insight for an affordable and natural antileishmanial with high efficacy and less toxicity., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)