Evaluation of mycochemical composition and in vitro sporulation inhibition activities of selected Nigerian indigenous mushrooms against Eimeria oocysts.

Abstract

This study was on comparative sporulation inhibition activities of five mushroom species (Ganoderma resinaceum, G. lucidum, Trametes elegans, T. gibbosa, and Pisolithus arhizus) extracts by different solvents against three Eimeria species (Eimeria acervulina, E. maxima, and E. tenella) at different concentrations (25-75&#x202f;mg/ml) and incubation periods (24&#x202f;h and 48&#x202f;h). The results demonstrate substantial interspecific and solvent-, concentration-, and time-dependent variation in anticoccidial efficacy. Among the five mushroom species tested, P. arhizus emerged as the most potent inhibitor of Eimeria oocyst sporulation, achieving complete inhibition at relatively low concentrations, with values ranging from 74&#x202f;% to 100 across all Eimeria species and solvent extracts. This indicates an exceptionally potent anticoccidial effect of the P. arhizus extract. T. elegans and G. lucidum exhibited intermediate activity, while G. resinaceum and T. gibbosa were less effective. Even at 25&#x202f;mg&#xb7;ml&#x207b;&#xb9;&#x202f;, P. arhizus ethanol extracts suppressed &#x2265;&#x202f;80&#x202f;% of sporulation in all three Eimeria species. These levels exceed the maximal inhibition seen with T. elegans (84&#x202f;% in ethanol, 75&#x202f;mg&#xb7;ml&#x207b;&#xb9;, E. tenella) and G. lucidum (63&#x202f;%). The more modest suppression by G. resinaceum (peak at 46&#x202f;%) and T. gibbosa (peak at 34&#x202f;%) suggests comparatively lower content or accessibility of active metabolites. A clear dose-dependent pattern was observed across all species and solvents, with sporulation inhibition increasing significantly (p&#x202f;<&#x202f;0.05) with concentration. Temporal analysis revealed that inhibition at 48&#x202f;h was either comparable or slightly reduced compared to 24&#x202f;h in some extracts, suggesting partial degradation or reduced bioavailability of active compounds over time. Organic solvent extracts consistently outperformed aqueous extracts across all fungal species. Ethanol and methanol yielded the highest sporulation inhibition percentages, followed by ethyl acetate and water. The main secondary compounds obtained from the ethanol solvent are polar, such as phenolic compounds. Terpenes are mid-polar metabolites that are obtained from ethyl acetate. Across all treatments, E. tenella showed the highest susceptibility to the extracts, followed by E. maxima and E. acervulina. Findings of this study establish P. arhizus as a promising candidate for developing novel, natural anticoccidial agents. These findings necessitate further quantitative analysis to isolate and identify the specific compounds responsible for the observed efficacy spectrum.