Assessment of the role of anthocyanin standardized elderberry (Sambucus nigra) extract as an immune-stimulating nutraceutical of Nile tilapia, Oreochromis niloticus.

Abstract

The study of nutraceuticals and their connection to immunity is an expanding field of research. The use of nutraceuticals to alleviate stress and enhance immunity in adverse aquaculture environments have been examined to a certain extent. To elucidate the understanding, we focused on the immunological effect of membrane-separated 13% anthocyanin standardized elderberry (EB) extract with maltodextrin excipient, widely used first-line nutraceuticals to augment the immunity, in aquaculture fish, Nile tilapia. To evaluate the potential of EB-extract, we assessed their capability to enhance lymphocyte proliferation and interleukin-2 production in an in-vitro condition using spleen and thymus lymphocytes. The experiments on spleen and thymus T-cells demonstrated significantly higher T-cell proliferation by EB-extract when lectin mitogen Con A was present as a stimulator. Likewise, our spleen B-cell proliferation result reveals a significant effect of EB-extracts, along with B-cell stimulator non-lectin mitogen LPS. Further, the quantification of IL-2 indicates elevated IL-2 levels when spleen T-cells were cultured with EB-extracts and with Con A present as a stimulator. These suggest that 13% anthocyanin standardized EB-extracts can aggrandize fish cells' cellular and humoral immune responses. With further research, elderberry extracts could be used to supplement commercial feed in aquaculture to reduce stress and stimulate the immune response.