Feeding of nano scale oats β-glucan enhances the host resistance against Edwardsiella tarda and protective immune modulation in zebrafish larvae

In this study, we prepared and characterized the oats origin of nano scale β-glucan (NBG) and investigated the immunomodulatory properties in zebrafish larvae. Newly prepared NBG (average particle size of 465 nm) was fully soluble in water. Zebrafish larvae survival rate was increased against pathogenic bacteria Edwardsiella tarda, when NBG was added to the water (500 μg/mL) compared to NBG non-exposed controls. Moreover, quantitative real time PCR (qRT-PCR) results showed up-regulation of immune functional genes including TNF-α, IL-1β, β-defensin, lysozyme, IL 10, IL 12 and C-Rel indicating higher survival rate could be due to stronger immunomodulatory function of NBG (500 μg/mL). Thus, non-toxic, water soluble and biodegradable NBG from oats could be considered as the potential immunostimulant for larval aquaculture.