Unlocking the Antiadipogenic Potential of Carotenoids From <i>Galdieria phlegrea</i>

Oxidative stress, a sedentary and inactive lifestyle, or a high-fat diet are among the main causes responsible for the alteration of skin topography, a complex multifactorial disorder of the deeper layers of the skin, mainly caused by an impairment of lipid production, degradation, and storage. Natural bioactive compounds can improve skin health and appearance as well as reassure consumers' about the safety of the molecules used in cosmetics. Carotenoids from microalgae are receiving attention because of their potent antioxidant activity. Here, a carotenoid extract from Galdieria phlegrea residual biomass was successfully explored for its ability to inhibit in vitro skin hyperpigmentation, to interfere with 3T3-L1 adipocytes differentiation, as well as to affect de novo lipogenesis and enhance lipolysis in mature adipocytes. The same set of experiments was done in parallel on the extract obtained from fresh biomass, but no biological activity was observed. The obtainment of a high-value class of molecules in a cascade approach highlights the importance of a biorefinery approach to obtain active extracts with a concurrent lowering of the overall process costs.