Polysorbate 80 Differentially Impacts Erinacine Production Profiles in Submerged Cultures of Hericium

The mycelia of Hericium erinaceus contain neuroprotective cyathane diterpenoids (e.g., erinacine A). There is evidence that cultivation of submerged mycelia with surfactants increases glucose uptake and biomass, but the impact on erinacine production is unknown. Here, we tested the impact of glucose and polysorbate 80 on the mycelial erinacine profiles of five Hericium strains cultivated under submergence, including those of Hericium erinaceus, Hericium americanum, and Hericium coralloides. Metabolite profiling confirmed that mycelial extracts contained 13% to 91% of the erinacines A, C and P in additive-free cultures of all strains, with the remainder secreted to the culture medium. Overall, erinacine P production was several orders of magnitude greater than that of the other erinacines, except for H. erinaceus (DAOMC 251029), where erinacine C was most evident. H. coralloides (DAOMC 251017) produced the greatest concentrations of erinacines A and P. For the most part mycelial erinacine concentrations were reduced in cultures co-supplemented with glucose and polysorbate 80. This treatment caused an 83-100% reduction in the concentrations of erinacines A, C, and P in the mycelial extracts of most strains. By contrast, there was evidence that glucose and polysorbate 80 had no effect on erinacine A production within mycelia of H. americanum, and erinacine P concentrations in H. erinaceus (DAOMC 251029) and H. americanum (DAOMC 251011). In most strains, the secretion of erinacines to the culture medium declined with glucose and polysorbate 80. Conversely, these additives increased the concentrations of erinacines C and P in the culture medium filtrate of H. americanum (DAOMC 21467) and yielded more secreted erinacine P in H. erinaceus (DAOMC 251029). The information provides feasible strategies to produce mycelia with unique erinacine profiles including those rich in erinacine P.