From crown to cosmetics: Exploring the efficacy of an upcycled pineapple biopolymer in sustainable skincare, suncare and hair care applications

OBJECTIVE: Nearly 50% of the pineapple by weight is discarded after harvesting due to various processing methods, resulting in huge amounts of waste containing beneficial compounds and metabolites that have high valorization potential across multiple industries. Agricultural waste, expanding industrialism and human transportation have increased airborne pollution and ultraviolet (UV) exposure, which exerts negative effects on skin, hair and overall health. As such, an eco-conscious cosmetic ingredient creating a physical barrier between the skin surface and environmental aggressors with properties to combat the subsequent cellular effects of these harmful factors is highly sought after. Accordingly, we investigated the capacity of an upcycled film-forming pineapple biopolymer to provide a comprehensive array of benefits for utilization in skincare, sunscreen and haircare formulations while facilitating environmental sustainability. METHODS: We developed a novel Pineapple Leaf Fibre Crosspolymer (PALF) by subjecting discarded pineapple leaf fibres to a proprietary manufacturing process involving alkali treatment, acidic hydrolysis and yeast fermentation. Next, efficacy was examined to determine the cosmetic potential of PALF in skincare, sunscreen and haircare formulations. In vitro and ex vivo experiments evaluated PALF for antioxidant, anti-inflammatory, antipollution, UV protection and pigment-dispersing properties. Furthermore, in vivo studies were implemented to elucidate the impact of PALF on dermal carbon deposition, long-wear foundation transfer resistance, skin hydration, barrier function, sensory experience and perceived hair benefits. RESULTS: The in vitro and ex vivo experiments demonstrated PALF reduced excessive oxidative stress, quelled inflammation, inhibited the negative effects of airborne pollution and UV exposure, while exhibiting effective pigment-dispersing properties. With respect to in vivo studies, PALF reduced dermal carbon deposition while improving long-wear foundation transfer resistance, skin hydration, barrier function, sensory experience and perceived hair benefits. CONCLUSION: Taken together, the eco-friendly PALF protects against harmful environmental aggressors while exerting other beneficial effects on the skin and hair. Importantly, PALF forms a physical barrier on the skin surface, limiting pollution contact with the skin with the capacity to blunt the cellular effects of harmful environmental factors. Collectively, the present investigation demonstrates PALF retains a comprehensive array of benefits in a wide range of cosmetic formulations and applications while facilitating environmental stability.