From tilapia (Oreochromis niloticus) farming, the by-products have been identified as a source of collagen that could be used for the development of dermocosmetics or pharmaceutical products. However, the characteristics of collagen related to a specific strain or culture must be well defined prior to its application. Collagen was extracted from the skin of three strains of tilapia: red YY males (YY: two Y-type sex chromosomes), XX gray females, and the F1: offspring of crossing red YY males with XX gray females; at different ages in the adult phase, using acetic acid and pepsin enzyme. The characteristics of acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) were shown by SDS-PAGE band profiles to be similar to bovine collagen type I (SIGMA), the PSC of gray tilapia being more fragile to temperature changes, consistent with the results of fractional viscosity. The characteristics of the F1 progeny were prioritized for being a commercially productive and sustainable source for the extraction of collagen, and the ASC form, being the one with the greatest stability and advantage over PSC, of importance to our investigations, leads to a controlled digestion as in the case of peptide induction, and also in the development of natural products in the pharmaceutical and/or dermocosmetic industry. Evaluations of the triple helix structure by FT-IR, X-ray diffraction and UV–visible spectroscopy give similar results between the strains: red, gray, and F1, and between ages in the adult form F1 (15, 24, and 36 months of age). Consequently, the skin of tilapia in adult form is recommended sustainably for up to 24 months of age where the collagen is obtained with the use of acetic acid without enzymatic treatment.

Herbal extracts have been widely used in dermocosmetics as a source of biomolecules and also as a natural claim. Fruits from Caesalpinia spinosa show great potential for their polyphenolic content, preservative, and film-forming features, as previously reported in specialized literature; however, the toxicity requires investigation. We explored Oreochromis niloticus (tilapia) in larval, alevins, and juvenile stages to evaluate the ex vivo and in vivo genotoxicity and in vivo acute and chronic toxicity of C. spinosa aqueous extract in different concentrations. Cytotoxicity, animal behavior, morphological deformities, and DNA damage were evaluated. Our results showed genotoxic effect in ex vivo tests, but no DNA damage in in vivo erythrocytes. We suggest a mechanism of cell permeability involved in the toxicity of C. spinosa aqueous extract. Internal validation showed the feasibility of O. niloticus applied for toxicity evaluation. Further studies could contribute for better understanding the uses and safety of C. spinosa in cosmetics and topical pharmaceutical products.

Obtaining new cosmetic ingredients, mainly from sustainable sources, as novel excipients or even active compounds is noteworthy for the cosmetic industry to enhance new innovative dermocosmetics. Thus, it is essential to establish the safety of these new ingredients to avoid adverse events, mainly those associated with clastogenic effects from the chemical compounds used for collagen extraction. In this study, we evaluated solutions of chemical compounds used in the collagen extraction process from tilapia skin (Oreochromis niloticus). The cytotoxic and genotoxic effects of the solutions used in the collagen extraction process were 10.0, 1.0, 0.5, and 0.1% n-butanol. Solutions were evaluated by the Allium test and the comet assay in peripheral white blood cells. The residual water from the final skin wash in the pre-treatment phase and the 0.5% lyophilized collagen extract were also investigated. The absence of cytotoxic and genotoxic activity was demonstrated in the collagen extract, despite the fact that n-butanol showed DNA damage, both in the root cells of Allium cepa and in the white blood cells of human peripheral blood. Therefore, we note the necessity to carry out genotoxicity tests to guarantee the absence of contaminants in the collagen extract for cosmetic purposes