Evaluation of <i>Zamia floridana</i> A. DC. Leaves and Its Isolated Secondary Metabolites as Natural Anti-Toxoplasma and Anti-Cancer Agents Using In Vitro and In Silico Studies

Toxoplasmosis and cancer are life-threatening diseases with worldwide distribution. However, currently used chemosynthetic treatments are not devoid of their own intrinsic problems. Natural metabolites are gaining attention due to their lower side effects. In this study, we investigated for the first time Zamia floridana leaves extract and its different fractions for their toxoplasmocidal activity, using Virulent RH Toxoplasma gondii, and cytotoxic activity against MCF-7 and HCT-116 cancer cell lines using MTT assay. The n-butanol fraction was the most potent fraction against T. gondii with an EC50 of 7.16 ± 0.4 µg/mL compared to cotrimoxazole (4.18 ± 0.3 µg/mL). In addition, the n-BuOH fraction showed a significant cytotoxicity against MCF-7 and HCT-116 with IC50 of 12.33 ± 1.1 and 17.88 ± 1.4 µg/mL, respectively, compared to doxorubicin (4.17 ± 0.2 and 5.23 ± 0.3 µg/mL, respectively), with higher safety index against normal cell line (WISH). Therefore, the n-BuOH fraction was investigated for its phytochemicals using extensive chromatographic techniques, which led to the isolation of six compounds that were fully characterized using different spectroscopic techniques. Three biflavonoids (1, 2 and 4) in addition to two phenolic acid derivatives (3 and 5) and a flavonoid glycoside (6) were isolated. Compounds (1, 3, 5 and 6) were reported for the first time from Z. floridana. In silico docking studies for toxoplasmocidal and cytotoxic effects of these compounds revealed that compounds (1, 2, 4 and 6) have promising inhibition potential of either thymidylate synthase-dihydrofolate reductase (TS-DHFR) or cyclin dependent kinase 2 (CDK2) target proteins. This study is considered the first report of chemical and biological investigation of Z. floridana leaves

Papaverinol-N-Oxide: A Microbial Biotransformation Product of Papaverine with Potential Antidiabetic and Antiobesity Activity Unveiled with In Silico Screening

Bioconversion of biosynthetic heterocyclic compounds has been utilized to produce new semisynthetic pharmaceuticals and study the metabolites of bioactive drugs used systemically. In this investigation, the biotransformation of natural heterocyclic alkaloid papaverine via filamentous fungi was explored. Molecular docking simulations, using protein tyrosine phosphatase 1B (PTP1B), &alpha;-glucosidase and pancreatic lipase (PL) as target enzymes, were performed to investigate the antidiabetic potential of papaverine and its metabolites in silico. The metabolites were isolated from biotransformation of papaverine with Cunninghamella elegans NRRL 2310, Rhodotorula rubra NRRL y1592, Penicillium chrysogeneum ATCC 10002 and Cunninghamella blackesleeana NRRL 1369 via reduction, demethylation, N-oxidation, oxidation and hydroxylation reactions. Seven metabolites were isolated: namely, 3,4-dihydropapaverine (metabolite 1), papaveroline (metabolite 2), 7-demethyl papaverine (metabolite 3), 6,4&prime;-didemethyl papaverine (metabolite 4), papaverine-3-ol (metabolite 5), papaverinol (metabolite 6) and papaverinol N-oxide (metabolite 7). The structural elucidation of the metabolites was investigated with 1D and 2D NMR and mass spectroscopy (EI and ESI). The molecular docking studies showed that metabolite 7 exhibited better binding interactions with the target enzymes PTP1B, &alpha;-glucosidase and PL than did papaverine. Furthermore, papaverinol-N-oxide (7) also displayed inhibition of &alpha;-glucosidase and lipase enzymes comparable to that of their ligands (acarbose and orlistat, respectively), as unveiled with an in silico ADMET profile, molecular docking and molecular dynamics studies. In conclusion, this study provides evidence for enhanced inhibition of PTP1B, &alpha;-glucosidase and PL via some papaverine fungal transformation products and, therefore, potentially better antidiabetic and antiobesity effects than those of papaverine and other known therapeutic agents