ABSTRACT

Auricularia auricula-judae, the third most cultivated edible fungus globally, holds significant potential for applications in cosmetics, food, and pharmaceuticals. This study explores the utilization of Terminalia catappa leaves as a substrate for the cultivation of A. auricula. Terminalia catappa leaves were incorporated into the cultivation process at different stages, including as a culture media additive and a substrate for spawn material. The study aims to investigate the effects of Terminalia catappa leaves on the vegetative growth of A. auricula. Results indicate that the 10% concentration of leaf extract exhibited optimal mycelial extension (8.40 ± 0.06cm) and density (very dense) compared to the control group (0% concentration), 8.33 ± 0.03cm appearing to be very dense. The concentrations above 20% partially inhibited mycelial growth while 80% and 100% exhibited complete inhibition. However, it can be said that there is no significant difference in the rate of mycelial extension between 0% and 10% as they grew almost simultaneously. The highest biomass was observed at 40% concentration (0.34 ± 0.04)g while  the liquid medium containing 0% had the highest biomass of (0.26 ± 0.02)g. Additionally, Terminalia catappa leaves, as a substrate material in the mother spawn preparation, showed varying effects on colonization rate. The substrate with no treatment showed faster colonization (14.00 ± 0.32 days) when compared to spawn containing other additives, whereas the addition of Calcium Sulphate hindered growth (complete inhibition). In conclusion, Terminalia catappa leaves have potential as a supplemental substrate component, particularly at lower concentrations, without significantly impacting the yield or colonization rate of A. auricula. However, their use as a primary substrate or spawn material is not recommended due to potential growth inhibition. Further research is warranted to explore underlying mechanisms and optimize the use of Terminalia catappa leaves in mushroom cultivation of Auricularia auricula.