Nutritional Composition, Antioxidant Activity, Cytotoxicity, and Enzymatic Potential of <i>Ficus nitida</i>-Associated <i>Tomophagus colossus</i>

Abstract

A fruiting body of a basidiomycete fungus was discovered growing on chopped Ficus nitida tree trunks in the student housing on the Assiut University campus during the course of this inquiry and a normal collecting operation in the Assiut Governorate, Egypt. Following the growth of the basidioma’s inner tissue on PDA, fungal mycelial growth was achieved. Internal transcribed spacer region (ITS) sequencing has allowed for the identification of the fungus as Tomophagus colossus. On the dry weight basis, chemical analysis of T. colossus AUMC 14536 basidioma revealed that it contains 28.81% carbohydrates, 25.34% crude fats, 23.44% crude fibers, 20.64% crude proteins, and 3.02% ash, in addition to potassium, phosphorus, calcium, selenium, iron, and zinc (133.59, 114.46, 6.27, 3.08, 1.28, and 0.73 mg/100 g dry weight, respectively). The total phenolic compounds (39.26 mg/g) and total flavonoids (5.62 mg/g) were also evaluated. The basidioma extract’s antioxidant activity was assessed as %DPPH radical scavenging activity with an IC50 of 4.15 µg/mL compared with a 1.89 µg/mL IC50 of ascorbic acid. In solid-state fermentation (SSF), the fungus could ferment broad bean straw, palm leaf hay, rice husk, rice straw, sugarcane bagasse, and wheat bran to produce endoglucanase, exoglucanase, laccase, pectinase, and xylanase in substantial amounts. Specific activity exhibited the highest values for endoglucanase (81.48 U/mg), exoglucanase (114.35 U/mg), pectinase (81.94 U/mg), and xylanase (70.18 U/mg) on the rice husk, while the peak of laccase activity (94.27 U/mg) was gained on bean straw. This is the first assessment of the organism’s nutritional value, amino acid content, antioxidant activity, and enzymatic capabilities in Egypt.

Keywords

• amino acids
• antioxidant
• biodiversity
• cytotoxicity
• <i>Ficus</i>
• ITS