Assessment of the effect of iron and selenium fortification on the amino acids profile of Pleurotus ostreatus

Pleurotus ostreatus mushroom is a source of dietary elements and can be enriched with minerals due to their ability to absorb nutrients from the substrate they are cultivated upon and bio-accumulate them as functional organic compounds during growth. This study investigated phytochemical, proximate and amino acids profile of P. ostreatus enriched with iron (Fe) and selenium (Se). Quantitative phytochemical study of mineral fortified and non-fortified mushroom showed the presence of tannin, alkaloids, phenol, saponin and flavonoid. Tannin levels were abundant in iron-fortified mushrooms (8.31 mg/g) and non-fortified mushrooms (6.37 mg/g). Flavonoids were abundant in non-fortified mushrooms (3.12 mg/g) and iron-fortified mushrooms (2.44 mg/g), respectively. Selenium-fortified mushrooms had highest fat content (14.20%), crude fibre (12.13%) and ash (7.50%), respectively. Seventeen (17) types of essential and non-essential amino acids were found in cultivated mushrooms; eight (8) in non-fortified and nine (9) in selenium and iron-fortified mushrooms. Tryptophan (83.33 mg/100 g) was most abundant in iron-fortified. Second most abundant were isoleucine (76.7 mg/100 g), histidine (60.0 mg/100 g), and methionine (22.33 mg/100 g) in non-fortified mushrooms, respectively. Glycine (80.00 mg/kg) and cysteine (60.00 mg/100 g) were most abundant in non-fortified mushrooms. Alanine, glutamic acids, serine, aspartic acid, proline, arguine, and tyrosine were least abundant and ranged from (6.51 mg/100 g to 1.21 mg/100 g) in non-fortified, iron-fortified and selenium-fortified mushroom, respectively. Results from this study revealed that Fe and Se-fortified Pleurotus ostreatus could serve as a rich vehicle source of essential amino acids for animal and human consumption.