From waste to beauty: Evaluation of the utilization of by-products of watermelon (Citrullus lanatus) and eggshells of hen (Gallus gallus do mesticus) as ingredients for cosmetic products.

Abstract

The current cosmetic industry is seeking new, environmentally friendly, and cost-effective raw materials. Therefore, by-products from the agro-food industry become an interesting opportunity, as some of them possess bioactive compounds with potential cosmetic use. This study investigated the composition of watermelon and eggshell waste for the extraction and potential use of antioxidants and collagen. The ex-traction of antioxidants from three fractions of watermelon waste (green part, white part, and seed) and eggshell was evaluated. For the watermelon fractions, methanol extraction was used, obtaining antioxidant extracts with inhibition percentages of 68.50%, 56.93%, and 82.04% for ABTS and 48.3%, 17.7%, and 68.5% for DPPH, respectively. On the other hand, a mineral composition analysis was performed on the eggshell using ICP-MS, finding calcium and magnesium as its primary constituents. Additionally, the collagen content and type present in the egg membrane were determined, resulting in a content of 500 mg/100 g, mainly represented by type X collagen, with a size of 45 KD. These results recognize the technical potential of some components present in these waste materials; however, it is necessary to delve deeper into the technical-economic feasibility, regulatory framework, and scalability of the process for effective incorporation of these matrices into the global cosmetic industry.