Bioprospecting Suitability of Selected Basidiomycetes for Biocoloration and Bioremediation Potential

Abstract

Prospects for utilizing edible fungi (Basidiomycetes) in cross-cutting industrial applications have not been fully explored. This study sought to bioprospect for bioactive molecules with colouring potential from golden yellow Pleurotus citrinopileatus and an exotic pink P. djamor and determine their application in food and non food (textile industry). Data obtained were analysed statistically using 1-way ANOVA, with multiple comparison done with Tukey test at α=0.05.These mushrooms were grown on seven selected substrates namely wheat straw, rice straw, sugarcane baggase, bean straw, banana fibres, maize stovers, sawdust and yields determined. Beans straw and rice straw reported earnest pin head formation with a significant biological efficiency of 72%, 70% for P. citrinopileatus and 68%, 62% for P. djamor respectively. These substrates reported a significant mean basidiocap number and pin head abortion from the five substrates (p<0.05). There were no statistical difference in growth parameters between wheat straw and sugarcane baggase for both species (p>0.05). Sawdust reported poor growth parameters. Extraction was done in four phenological states and subjected to phytochemicals screening, determination of total polyphenols content, and Total Flavonoid content, Total carotenoids, β-Carotene, Lycopene, antioxidant activities using ABTS assay, DPPH assay, and Ferricyanide reducing power. Standard methods were used for qualitative analysis; Folin Ciocalteu assay for Total polyphenols, Aluminium chloride reduction method for total flavonoid. Phytochemical components identified included saponin, terpenoids, flavonoids, and polyphenols. Primordials exhibited increased concentration of phytochemicals, which correlated positively (r≥0.9, p<0.05) with total phenolics (19.025±0.847; 13.803±0.797mg GAE/g dwt), total flavonoids (14.824±0.89; 10.619±0.785mg QE/g dwt) and total antioxidant properties. Antioxidant properties were concentration dependent with ethanol extracts exhibiting statistically significant higher values than water extracts. A Liquid Chromatography quadrupole time of Flight Mass Spectrometry was used for profiling metabolites across these phenologies. ChemSpider™ database was used for putative identification of compounds based on their empirical formula and accurate mass. A total of 21 compounds were identified based on their empirical formula and accurate mass. Extracts from primordials have potentiated health benefits. Formulated Mushroom powder was incorporated into yoghurt to assess psysicochemical and acceptability profiles based on organoleptic tests. Yoghurt formulated with mushroom powder at 1.5% (w:v) and 3% w:v) were statistically better in acceptance than 5% (p>0.05). The 5% formulated had significant colour properties but poor viscosity and pH with extended setting time (18hrs). Mushrooms have a potential in fortifying dairy products. One set of mushroom powder was xii subjected for fastness study using mordanted fabric. Fabrics exhibited varied colour shades depending on mordants used. Copper sulphate showed significant intensity of colouration with lower fastness than Alum for both species dye bath (p>0.05). Unmordanted fabrics exhibited significant colour fast. Spent substrates were tested for degradation and discolour Levafix Blue CA based on optical density. Discolouration of levafix by spent substrates was concentration dependent for each treatment. Biodegradation by 50gm SMS exhibited significant difference between the two species, this signified the potential of spent substrates in mycoremediation.