No abstract

Mushrooms are a group of fungi that are diverse and in the Niger Delta region; there are various species, some of which share similar morphological features. Over the years, mushrooms have been put to several important uses ranging from food, nutraceuticals, feed for livestock, and more recently bioremediation, hence, the need for an accurate approach of identification is eminent. This study aims to identify three mushroom samples with the potential for crude oil degradation using molecular tools. The molecular identification of the mushrooms was carried out with the ITS (Internal Transcribed Spacer) region to analyze their genetic diversity. The three mushroom samples were identified as Pleurotus ostreatus, Pleurotus floridanus and Lentinus squarrosulus. The blast results showed 86.0%, 97.9%, and 88.4% for Pleurotus ostreatus, Pleurotus floridanus and Lentinus squarrosulus respectively for sequence similarity. The samples were assigned unique accession numbers on GenBank The use of molecular characterization gives reliable results to the species level. The results from this study have increased the database of Pleurotus and Lentinus DNA and serve as a basis for the identification of unidentified species by comparing their PCR amplified sequences with ITS primers.

Fungi play vital roles as decomposers. White rot fungi are an eco-physiological group that degrades wood by the secretion of specialized extracellular enzymes including lignin-modifying enzymes. There is growing interest in the use of extracellular enzymes for bioremediation. This study determined the Lignin Modifying Enzymes (LMEs) associated with two species of mushroom, Pleurotus ostreatus and Lentinus squarrosulus. The qualitative study was conducted using agar medium substituted with chromogenic substances to determine the production of LMEs by the species. The appearance of colour change and clearance due to reaction with chromogenic substrates were used to determine LMEs production by the fungi. The results showed that Pleurotus ostreatus and Lentinus squarrosulus tested positive by the appearance of light brown colouration, reddish-brown colouration and discolouration of media for overall polyphenol oxidase, Laccase and Peroxidase activity, respectively. The study showed that the species studied are candidates for large scale production of LMEs that can be utilized as an eco-friendly solution for bioremediation of contaminated sites.