Phytochemical screening of wild Ganoderma species harvested from different ecological zones in Nigeria

Abstract

The Ganoderma genus is known to have curative properties against a wide range of human illnesses. This study seeks to examine the presence and quantity of phytochemicals in wild Ganoderma species collected from five ecological zones in Nigeria. The results revealed the presence of saponins, alkaloids, flavonoids, phenols, tannins, coumarin, steroids, terpenoids, triterpenes and anthraquinones in ten Ganoderma species. Saponin levels ranged from 1.10% in G. applanatum to 2.80% in G. lucidum (GALAG). Notably, G. lucidum (GALAG) and G. lucidum (GOYO2) exhibited significantly higher saponin content (2.80% and 2.51%, respectively). Alkaloid percentages were significantly higher in G. lucidum (4.82 ± 0.04%) and G. resinaceum (4.69 ± 0.05%) compared to other species. Flavonoids varied substantially, as G. sinensis demonstrated the highest flavonoid content (3.44 ± 0.068 QE), significantly surpassing all others, followed by G. resinaceum 2 (2.85 ± 0.040 QE) and G. leucocontextum (2.66 ± 0.002 QE). Phenol content, measured as gallic acid equivalents (GAE), was highest in G. resinaceum 2 (1.82 ± 0.030 GAE) and G. sinensis (1.57 ± 0.037 GAE), showing significant differences (P < 0.05). Tannin content was most pronounced in G. applanatum (1.14 ± 0.000 GAE) (GAKOG) and G. resinaceum 2 (1.08 ± 0.010 GAE) (GABUK), with significant differences (P < 0.05) from others. Interestingly, the lowest tannin concentrations (0.06 ± 0.000 GAE) were observed in G. lucidum (GIMO). There were significant differences (P < 0.01) across all phytochemical parameters among the Ganoderma species. Ganoderma resinaceum, G. sinensis, and G. applanatum emerged as the most promising candidates for pharmaceutical exploration, particularly for their elevated levels of alkaloids, flavonoids, and tannins. Furthermore, G. resinaceum 2 emerged as the most phytochemically enriched species, leading in four out of five phytochemical categories—marking it a strong candidate for functional food and pharmaceutical development pipelines.