| Abstract |
Extracts of Botryococcus braunii and Nannochloropsis oculata were evaluated for inhibitory activity against acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and tyrosinase (TYRO) and capacity to attenuate hydrogen peroxide (H2O2)-induced injury in the human dopaminergic cell line SH-SY5Y. We also report the antioxidant activity, the total phenolic content (TPC) and the fatty acid (FA) profile of these microalgae. Both species had low levels of TPC and considerable amounts of polyunsaturated fatty acids (PUFA). The highest radical scavenging activity (RSA) against 1,1-diphenyl-2-picrylhydrazyl (DPPH) was observed in the acetone extract of B. braunii and in the diethyl ether extracts of both strains. The acetone extract of B. braunii had the highest RSA against 2,2 -azino-bis(3-ethylbenzothiazoline-6-sulphonic acid). The extracts had a higher capacity to chelate iron than copper, and the highest iron chelation was achieved with the hexane extract of N. oculata. The diethyl ether and water extracts of the latter species also displayed the highest copper chelation. Except for the acetone extract of B. braunii and the water extract of N. oculata, all samples inhibited AChE, especially the hexane extract of N. oculata. Samples had moderate BChE inhibition and no effect towards TYRO. Almost all samples effectively protected neuronal cells against oxidative stress induced by H2O2. These results suggest possible novel applications of biomass from those microalgae in the pharmaceutical industry and/or as functional foods. |
