Abstract:
This study aimed to analyze the chemical composition and biological activities
of grey oyster mushroom. Chemical composition analysis revealed that grey oyster
mushroom contained protein as the main component at 29.38 g/100 g, followed by
carbohydrates at 45.61 g/ 100 g, while fat content was low at only 2. 20 g/ 100 g.
Additionally, dietary fiber was found at 9.04 g/100 g, and the energy content was 355.92
kcal/100 g. Extraction using methanol as solvent by maceration method yielded 4.6%
crude extract. Antioxidant activity testing using DPPH method showed that the extract
had high antioxidant activity of 79.95%, close to the Trolox standard at 98.55%. Using
ABTS method, antioxidant activity was 74.98%, and FRAP method showed a value of
108.64 mg ascorbic acid per gram of extract. Total phenolic content was 2.36 mg tannic
acid equivalent per gram dry weight. Fatty acid analysis revealed saturated fatty acids at
0.50 g/100 g, with Palmitic acid as the main component. Unsaturated fatty acids were
1.70 g/100 g, with cis-9,12-Linolenic acid as the main component at 1.53 g/100 g. No
trans fatty acids were detected. Among Omega fatty acids, Omega-9 was highest at 1.53
g/100 g. Amino acid analysis showed diverse amino acids, with Glutamic acid being the
highest at 3,144.40 mg/100 g, followed by Aspartic acid and Alanine. Essential amino
acids found in high amounts included Leucine, Valine, Lysine, and Isoleucine.β-glucan
structure analysis using FTIR spectra technique showed important peaks consistent with
β-glucan standard, with peaks at 3307.54, 2928.68, 1641.01, 1371.69, 1149.55, 1030.71,
and 830. 39 cm- 1, indicating the presence of hydroxyl groups, aliphatic chains, and
polysaccharide structures.