Enhancement of mycelial biomass and lignocellulolytic enzymes of milky mushroom Calocybe indica through supplementation with organic amendments

Abstract

Milky mushroom (Calocybe indica) also known as tropical mushroom or summer mushroom has significant attributes of milky white colour with high nutritive value and long shelf life. The yield performance of milky mushrooms again depends on the secretion of lignocellulolytic enzymes that further influence the colonization of mycelium on the substrates. In the present study, organic supplements viz. cakes of cotton, groundnut, sesamum, coconut cake, neem cake, powdered moth bean, red gram, horse gram, green gram, soya bean, lab-lab, maize, rice bran and wheat bran amended at 1% and 5% concentration induced profuse mycelial growth and enhanced ligninolytic enzyme secretion by Calocybe indica under in vitro conditions. The results revealed that wheat bran and red gram supplements at 5 % concentration in PDA medium were found to influence the mycelial growth on the 7th day (68.67 mm and 62.33 mm respectively). Similarly, both wheat bran and red gram supplements at 5 % in liquid medium supported increase in the biomass production of C. indica on the 15th day (1.83 and 1.40 g) followed by horse gram. The influence of organic supplements on the induction of lignocellulolytic activity showed that the maximum cellulase and xylanase activity (1.7 U/min/g and 0.835 U/min/g respectively) and laccase activity (1.6 U/min/g) were noticed in the substrate supplemented with wheat bran followed by horse gram (1.3 U/min/g) at 5% concentration under solid-state fermentation. However, the lignin peroxidase activity was maximum (0.59 U/min/g) in combination with wheat bran (2.5%) and red gram (2.5%) and manganese peroxidase activity was maximum in wheat bran supplement (0.3 U/min/g) at 5% concentration. It is inferred that amending organic supplements viz. wheat bran, horse gram and red gram to substrates enhance the mycelial growth, biomass production and lignocellulolytic enzyme secretion of C. indica and offers scope for yield improvement.