Anti-skin glycation and collagen level stimulation of brown seaweed extracts and their compositional characteristics

Abstract

This study aimed to investigate anti-skin aging potential of the extracts from three Southern Australian brown seaweeds: Ecklonia radiata (ER), Cystophora moniliformis (CM), and Cystophora siliquosa (CS). These extracts and two positive controls (Aminoguanidine (AG), a drug candidate for anti-glycation, and phloroglucinol (PG)) were tested for their inhibition of glycation reaction using in vitro non-cellular bovine serum albumin (BSA)-glucose and methylglyoxal (MGO) models. The safe doses were also established by toxicity test with human skin fibroblast cell by MTT assay. Among three extracts studied, ER showed the highest toxic, but far less than both positive controls. The CM and CS extracts at 500 μg/mL showed inhibition of glycation activity, approximately 65–90 % compared to AG (15–40 %) and PG (15–20 %) at 20 μg/mL. In addition, the stimulation of collagen and elastin levels using an in vitro cell-based assay was evaluated. Relative to the control (water without samples), the CM and CS extracts at concentration greater than or equal to 250 μg/mL significantly increased the collagen levels of human skin fibroblast cells up to ∼16.5 folds, while there was no significant increase in elastin levels by most seaweed extracts. Furthermore, compositions of all extracts were characterized. Apart from high polysaccharide contents, phlorotannin which accounts for 17–23 % of CM and CS might be responsible for their anti-skin aging benefits. These findings demonstrate that the brown seaweed extracts CM and CS have high potential to be used as skin anti-aging supplements with anti-glycation and collagen stimulation benefits, worthy of further in vivo studies.