Green synthesis of zinc oxide nanoparticles for the industrial biofortification of (Pleurotus pulmonarius) mushrooms

Abstract

Zinc malnutrition is major health problem in children and women of reproductive age (WRA) in developing countries. This study aimed to find nutritionally balanced food at an affordable cost. For this purpose, Pleurotus pulmonarius (Mushroom) is fortified with zinc oxide nano particles (ZnO-NPs) synthesized from Nigella sativa seed extract. ZnO-NPs were characterized using UV visible and FTIR Spectroscopy, SEM-EDX, XRD, PSA and Zeta potentials. ZnO-NPs were sprayed in different concentrations on substrate used for the cultivation of P. pulmonarius. Cultivated mushroom fruiting bodies were dried and powdered. Bio absorption of zinc was calculated using atomic absorption spectroscopy. Zinc absorption increased by enhancing the number of nano particles spraying on lingo-cellulosic substrate. The controlled bag had 2.27 ± 0.00 mg of zinc content per 2 g of mushroom powder. The minimum amount (3.46 ± 0.16 mg/2 g of mushroom) of zinc micronutrient was absorbed by the bag having 50 mg spray of ZnO-NPs per Kg of the wheat straw. Maximum amount of bio accumulation was done by bag having 5000 mg spray of ZnO-NPs (10.46 ± 0.08 mg/2 g of mushrooms powder). Zinc fortification had a significant (p < 0.05) effect on the uptake of zinc by fruiting bodies. ZnO-NPs at the concentration of 200 mg per kilogram of substrate gave optimized value of biological efficiency [B.E] (40.2 % ± 0.25), while B.E decreased with the increase in ZnO-NPs spray due to bio accumulation of zinc with increased concentration of ZnO-NPs spray.