Antioxidant and antimicrobial properties of Pleurotus djamor (Rumph. ex Fr.) Boedijn enriched with selenium (Se) and zinc (Zn) nanoparticles

Samson, Debbarma

Antioxidant and antimicrobial properties of Pleurotus djamor (Rumph. ex Fr.) Boedijn enriched with selenium (Se) and zinc (Zn) nanoparticles

Date

2023

Authors

Samson, Debbarma

Publisher

Punjab Agricultural University

Abstract

The biofortification potential of biogenic selenium (Se) and zinc (Zn) NPs derived from P. djamor and P. sajor-caju were evaluated in terms of yield, protein content, antimicrobial activity, antioxidant and phenolic content. The fruit body extracts of P. djamor and P. sajorcaju were used for the synthesis of Se and ZnO NPs using the precursor salts (Na2SeO4 and ZnC4H6O4) at different concentrations (0.4 to 1.0 mM). The visual colour change in the extracellular extracts of Pleurotus spp. treated with salts were observed (deep orange red and white for Na2SeO4 and ZnC4H6O4, respectively). This visual color change indicated the formation of biogenic NPs for both Se and Zn salts. Characterization of the NPs through UVVis spectroscopy revealed the optimized precursor salt concentration (0.4 mM for P. djamor and 0.8 mM for P. sajor-caju) and incubation time spans (72 hours for BioSeNPs-PD, BioZnONPs-PD, BioSeNPs-PSC and 96 hours for BioZnONPs-PSC). TEM imaging revealed spherical and roughly spherical shape for Se and ZnONPs, respectively with average particle size of 124 and 68 nm and 84 and 91 nm for PD and PSC BioSeNPs and BioZnONPs respectively. FTIR analysis revealed the presence of specific functional groups that denote the formation of characteristic nanoparticles. The maximum yield was found in BioZnNPs-PSC treated P. sajor-caju with an average fruit body yield of 56.16 ± 4.6 kg/100 kg dry straw. The BioZnNPs-PD treated P. djamor fruit body showed the highest total soluble protein content with a value of 2.98±0.07 mg g-1. The highest Zn level was observed in BioZnONPs (P. djamor) enriched wheat straw (133.1 ± 3.54 ppm), while Se content was highest (95.67 ± 2.98 ppm) in BioSeNPs fortified P. sajor-caju. BioZnONPs-PD exhibited the highest antibacterial activity against S. aureus, while BioSeNPs-PD and BioSeNPs-PSC were equally effective against E. coli. The biofortification of P. djamor with BioZnONPs exhibited the highest H2O2 and FRAP activities, while the fortification of P. sajor-caju with BioZnONPs showed the highest DPPH radical scavenging activity. The phenolic content of biofortified fruit bodies was significantly higher than the non-supplemented control, with biogenic Se/ZnO NPs was found to be more effective in enhancing phenolic content than inorganic supplementation. Thus, this study revealed that bio-fortification of P. djamor and P. sajor-caju with Zn and Se BioNPs played an important role in increasing the yield, protein content, elemental composition, antioxidant, and phenolic content, as well as exhibited antimicrobial activity which could be helpful in enhancing the nutraceutical value of mushrooms which may be used as a future food supplement.

Citation

Samson, Debbarma (2023). Antioxidant and antimicrobial properties of Pleurotus djamor (Rumph. ex Fr.) Boedijn enriched with selenium (Se) and zinc (Zn) nanoparticles (Unpublished M.Sc. thesis). Punjab Agricultural University, Ludhiana, Punjab, India.