Cosmetic Application of Cyanobacteria Extracts with a Sustainable Vision to Skincare: Role in the Antioxidant and Antiaging Process

Nature-based and sustainably sourced cosmetics have been dominating the area of skincare products worldwide. Due to their antioxidant and antiaging properties, compounds from cyanobacteria, such as carotenoids and phycobiliproteins, may replace synthetic ingredients in cosmetic formulations and may be used in products such as sunscreens, skincare creams, and makeup. In this study, we evaluated the potential of acetonic and aqueous extracts from cyanobacteria strains of the genera Cyanobium and Leptothoe and from strains within Synechococcales and Oscillatoriales orders, for use in cosmetics. Extractions were sequentially performed with acetone and water. Extracts were firstly analyzed for their toxicity to keratinocytes, fibroblasts, and endothelial cells (HaCAT, 3T3L1 and hCMEC/D3, respectively). The non-cytotoxic extracts were characterized in terms of total proteins, carotenoids, chlorophyll, phenols, phycobiliproteins, and analyzed for their antioxidant potential against the superoxide anion radical (O-2(center dot-)), and for their ability to inhibit key enzymes associated with the skin aging process. Aqueous extracts were richer in total proteins and phycobiliproteins. The aqueous extracts of Synechococcales cyanobacterium LEGE 181157 and Synechococcales cyanobacterium LEGE 181150 showed the highest value for total proteins (760.81 and 695.25 mu g BSA mL(dry extract,)(-1) respectively) and the best values regarding O-2(center dot-) scavenging (IC50 = 63.24 and 112.18 mu g mL(dry extract)(-1), respectively) with a significant negative correlation observed (p < 0.01). Moreover, aqueous extracts of Synechococcales cyanobacterium LEGE 181150 and Synechococcales cyanobacterium LEGE 181157 inhibited hyaluronidase, (IC50 of 483.86 and 645.06 mu g mL(dry extract)(-1), respectively), with a significant negative correlation with total proteins (p < 0.05), pointing out the contribution of these compounds to the biological activities observed. Acetonic extracts were richer in carotenoids and phenols. Zeaxanthin and beta-carotene were predominant among all strains, being present in higher amount in Cyanobium sp. LEGE 07175 (53.08 mu g mg(-1)) and Leptothoe sp. LEGE 181156 (47.89 mu g mg(-1)), respectively. The same strains also showed the highest values for collagenase inhibition at 750 mu g mL(dry extract)(-1) (32.88 and 36.61%, respectively). Furthermore, Leptothoe sp. LEGE 181156 exhibited the lowest IC50 value for tyrosinase inhibition (465.92 mu g mL(dry extract)(-1)) and Synechococcales cyanobacterium LEGE 181157 presented the best values for elastase inhibition (IC50 of 380.50 and IC25 of 51.43 mu g mL(dry extract)(-1)). In general, cyanobacteria extracts demonstrated potential for being used for antiaging purposes, with aqueous extracts being more efficient at free radicals scavenging and acetonic ones at avoiding degradation of dermal matrix components.

Automated summary

This study evaluated the potential of acetonic and aqueous extracts from different strains of cyanobacteria for use in cosmetics. The results showed that aqueous extracts were more effective in scavenging free radicals, while acetonic extracts were more effective in preventing degradation of dermal matrix components. Cyanobacteria extracts demonstrated potential for antiaging purposes.