Isolation and Preliminary Uterine Activity of Endophytic Fungi from Ficus exasperata
Egboche Isaac *
Department of Pharmaceutical Chemistry, Dora Akunyili College of Pharmacy, Igbinedion University, Okada, Edo State, Nigeria.
Samuel J. Bunu
Department of Pharmaceutical and Medicinal Chemistry, Faculty of Pharmacy, Niger Delta University, Bayelsa, Nigeria.
Enitome Bafor
Department of Pharmacology and Toxicology, College of Pharmacy, University of Benin, Edo State, Nigeria.
Usifoh O. Cyril
Department of Pharmaceutical Chemistry, College of Pharmacy, University of Benin, Edo State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Endophytic fungi are increasingly investigated as sources of secondary metabolites with potential biological activity. This study isolated endophytic fungi from the leaves of Ficus exasperata and evaluated the preliminary effects of selected fungal extracts on oxytocin-induced uterine contractions in an ex vivo mouse uterine model. Healthy leaves of Ficus exasperata were collected, surface-sterilised with 70% ethanol, cut into small segments and inoculated on malt extract agar supplemented with chloramphenicol. Fungal isolates obtained from the mid-rib and leaf-blade regions were subcultured and fermented on sterile rice medium for 28 days. The fermented material was extracted with ethyl acetate, concentrated and screened using isolated uterine horns from female Swiss albino mice mounted in a 10 ml organ bath containing physiological salt solution. The effects of the extracts on oxytocin-induced contraction frequency and amplitude were recorded and expressed relative to control responses. Among the tested extracts, FEMR2 produced the highest inhibitory effect, reducing contraction frequency by 85.00% and amplitude by 89.29% at the tested concentration. FEMR1, FELB1 and FELB2 showed lower inhibitory effects under the same experimental conditions. GC-MS analysis of the active FEMR2 extract indicated nonanoic acid and hexanoic acid as the predominant detected constituents, with area percentages of 24.42% and 15.99%, respectively. These findings indicate that an endophytic fungal isolate from Ficus exasperata contains metabolites capable of reducing oxytocin-induced uterine contractility. Further studies are required to confirm the fungal identity, isolate the active constituents, define concentration-response relationships and determine safety and mechanism of action.
Keywords: Endophytic fungi, Ficus exasperata, Fusarium sp, oxytocin-induced contractions, uterine activity, tocolytic activity, ethyl acetate extract, nonanoic acid, hexanoic acid, ex vivo assay, GC-MS