Optimization of Submerged Fermentation of Cordyceps militaris Mycelium with Coconut Broth

Abstract

Cordyceps militaris is a well-known medicinal mushroom celebrated for its immunomodulatory, antioxidant, and anti-inflammatory properties. This study explores the optimization of submerged fermentation for C. militaris mycelium using coconut broth as a sustainable nutrient medium. Coconut broth, consisting of coconut sugar, white sugar, and skim milk, was investigated for its effectiveness in promoting biomass yield and bioactive compound production. Using a 2-Level Full Factorial Design and Box-Behnken Design, the study examined varying concentrations of coconut sugar at 9 ◦Brix (100-200 ml/L), white sugar (10-30 g/L), and skim milk (5-10 g/L) to identify the most influential factors affecting the dry weight of C. militaris mycelium (DWCM). Statistical analysis revealed that skim milk, white sugar, and coconut sugar significantly contributed to increased DWCM, with contribution rates of 97.09%, 88.38%, and 74.67%, respectively. The steepest ascent method determined the direction of optimization, and the final regression model identified the ideal conditions for maximum DWCM (27.172 g/L) as 128.38 ml/L of coconut sugar at 9 ◦Brix, 25.476 g/L of white sugar, and 11.466 g/L of skim milk. These results indicate that coconut broth is an eco-friendly and suitable for scaling up production of bioactive compounds and developing innovative functional health products.