Microalgae and cyanobacteria as sources of bioactive compounds for cosmetic applications: A systematic review

Microalgae and cyanobacteria are rich in compounds with a wide diversity of biological activities that can be used to create new products with promising applications by the cosmetic industry. Many studies evaluating the bioactivities of microalgae and cyanobacteria extracts have been published, however perception of their potential use in cosmetic applications is still limited. The objective of this study was to systematically review the recent literature to assess the potential applications of microalgae and cyanobacteria in cosmetics. A total of 8498 articles mentioning antioxidant or anti-inflammatory properties, or cosmetic or nanosystem applications of microalgae and cyanobacteria extracts or biomass in the past 5 years were retrieved from different databases and the eligibility process was conducted applying inclusion and exclusion criteria. After that, 151 papers were selected of which 61 % cited antioxidant properties, 19 % cosmetic applications, 14 % anti-inflammatory potential, and 6 % nanosystem applications. The most reported genera were Chlorella (7 %), Arthrospira (7 %), Tetraselmis and Scenedesmus (6 % each). Crude extracts or biomass (56 %), pigments (14 %) and polysaccharides (9 %) were the type of microalgae- and cyanobacteria-based products most reported, Ninety-six percent of articles used in vitro methods with in vitro non-cellular assays being most cited (79 %) when compared with cellular assays (21 %), and only 4 % used in vivo approaches. Considering cosmetic applications, photoprotection (43 %), anti-cancer (melanoma) (19 %), and wound healing (16 %) were the most reported. A limited number of studies reported nanosystem applications, with metal nanoparticles and nanoemulsions as the most common nanosystem. The evidence found in the literature suggest that microalgae and cyanobacteria extracts are rich sources of bioactive products and compounds for cosmetic industry, which potential is far from being fully explored.

The authors acknowledge the financial support provided by the FCT Portuguese Foundation for Science and Technology (PD/BD/150264/2019) under the Doctoral Programme “Agricultural Production Chains – from fork to farm” (PD/00122/2012) and the Financiamento Plurianual de Unidades de I&D UIDB/04050/2020. This work was also supported by the “Contrato-Programa” UIDB/04050/2020 funded by national funds through the FCT I.P. This work was also funded by POCI-01-0247- FEDER-033784, Project Nº 33784, Extratoteca – Extratos de Microalgas com Elevado Valor-Acrescentado.