- Eluwa H.C, Njoku-Tony R.F, Ebe T.E & Agagwuncha C.U
- DOI: 10.5281/zenodo.24048276
- Global Academic and Scientific Journal of Multidisciplinary Studies (GASJMS)
Oil
pollution from artisanal refining has posed significant environmental
challenges in the Niger Delta, Nigeria, contaminating soils with polycyclic
aromatic hydrocarbons (PAHs) and heavy metals. This study evaluated the
bioremediation potential of two white-rot mushrooms, Lentinus subnudus and
Calocybe indica, on crude oil-contaminated soils from Ahoada West (AWS) and
Ogba Egbema (OES), compared to non-contaminated control soils. A 2 × 3
factorial experiment in a completely randomized design (CRD) with three
replicates was established, comprising two fungal species (Lentinus subnudus
and Calocybe indica) and three soil categories (AWS contaminated soil, OES
contaminated soil, and non-contaminated control soil). Soil samples (250 g
each) were placed in experimental pots, inoculated with 50 g of mushroom spawn
prepared on Potato Dextrose Agar (PDA), and incubated for 12 weeks. Sampling
was carried out biweekly to monitor PAH concentrations, nine heavy metals
(iron, Fe; manganese, Mn; copper, Cu; zinc, Zn; chromium, Cr; cadmium, Cd;
lead, Pb; nickel, Ni; and vanadium, V), and selected soil physicochemical
parameters. Data obtained were subjected to analysis of variance (ANOVA), and
means were separated using the least significant difference (LSD) at 5%. Results
indicated that Lentinus subnudus reduced PAH levels in AWS and OES soils by
54.2% and 61.5%, respectively, while Calocybe indica achieved reductions of
63.4% and 68.7% over the 12-week period. Heavy metal concentrations also
declined significantly; for example, copper residues decreased by 48.2–79.0%,
and zinc by 42.5–75.1%, depending on the fungal species and soil type. Both
fungi enhanced microbial community abundance and diversity, facilitating
pollutant degradation and improving soil quality. These findings demonstrate
that Lentinus subnudus and Calocybe indica are effective, eco-friendly agents
for the bioremediation of PAH- and heavy metal-contaminated soils, offering
sustainable strategies for soil reclamation in tropical oil-impacted
environments.
Keywords: Mycoremediation, Lentinus subnudus, Calocybe indica, PAHs, Heavy metals.
