Abstract:
Polyaromatic hydrocarbons (PAHs), which are the major by-products of fossil fuel burning, are released to the
environment with the immense growth of urbanization and industrialization. These pollutants are subsequently deposited on many
substrates including plant surfaces. Due to their toxicity, mutagenicity, carcinogenicity and recalcitrant nature, they can result in
many hazardous effects on human health. Application of endophytes in bioremediation has shown much promise in removing these
PAHs from contaminated substrates. In the present study, an attempt was made to isolate and identify endophytic fungi from the
moss plant Macromitrium sp. (frequently available) in Sapugaskanda (highly polluted) and Hettimulla (less polluted) areas in Sri
Lanka. Subsequently, their potential in degrading PAHs (naphthalene and phenanthrene) was investigated. Endophytes from the moss
were isolated following the surface sterilization method, and their physiological roles in degrading naphthalene and phenanthrene
were carried out using plate assays, spectrophotometric and high-performance liquid chromatography (HPLC) analysis. Most of the
endophytic fungi isolated from Macromitrium sp. were able to grow in Bacto Bushnell-Haas (BBH) medium incorporated with
naphthalene and phenanthrene, separately, displaying colony diameters more than 30 mm. As per the results obtained from
spectrophotometric and HPLC analysis, Penicillium oxalicum, Nigrospora oryzae, Aspergillus oryzae, A. aculeatus, Penicillium sp.1,
Penicillium sp.5, Eupenicillium sp.2 and Mortierella sp.1 degraded both naphthalene and phenanthrene more than 85%. The findings
of the present investigation provide some insight into how these endophytic fungi could be used for bioremediation of PAHs in
environmental sites where contamination prevails, and also open avenues for future research in the relevant field.