Cultivation and growth dynamics of endophytic fungi in a solid culture medium based on sugar beet pulp

The production of mycelium from endophytic fungi is of interest for applications ranging from inoculants and biofertilizers for crop production to fermentations for enzyme and metabolite production. The purpose of this study was to test the capacity of a solid growth medium based on beet pulp for growing different strains of endophytes.

The ergosterol content of inoculated medium was measured to estimate fungal growth. Several parameters related to the preparation of the growth medium, such as water content, calcium salts and incubation time, were evaluated. The greatest fungal biomass production was observed in a medium prepared with a 1:2 (beet pulp:water) ratio, containing calcium sulfate and carbonate. Strains belonging to different fungal species grew well in the growth medium finally selected, producing yields ranging from 50 to 500 g mycelium per kilogram of dry culture, after 22-27 days. Cultures containing up to 400 g beet pulp grew successfully, and could be scaled up.

A solid culture medium based on beet pulp supported the growth of diverse taxa of fungal endophytes. Both the water and calcium salt content of the growth medium affected the efficiency of mycelium production. Considering these factors, beet pulp medium was an excellent endophyte cultivation medium because of the high yield of fungal biomass observed, together with its ease of handling and scaling-up production. © 2019 Society of Chemical Industry.