Investigation of nutraceutical potential of the microalgae Chlorella vulgaris and Arthrospira platensis

The microalgae Chlorella vulgaris and Arthrospira platensis were evaluated as nutraceuticals. It was observed that Arthrospira platensis is richer in saturated fatty acids (FA) and Chlorella vulgaris richer in monounsaturated FA. Within polyunsaturated FA (PUFA), n3 PUFA content was below 1% in Arthrospira sp and over 10% in Chlorella vulgaris. This microalga had the lowest polyphenolic content. The highest value was found in the aqueous extract of Arthrospira platensis, 334 +/- 32 mg GAE per 100 g dw. Regarding DPPH, only aqueous extracts of Chlorella vulgaris yielded antioxidant activity with an inhibitory activity of 80 +/- 1%. ABTS results showed stronger inhibition through the aqueous extracts than through the ethanolic extracts, 89%-93% vs. 24%-32%. Concerning cytotoxicity, ethanolic extracts of Chlorella vulgaris induced a cell viability decrease of approximately 80%. The biochemical characterisation and bioactivity assessment of Chlorella vulgaris and Arthrospira platensis showed that these microalgae have potential for nutraceutical applications.