A closer look at the antioxidant activity of collagen obtained from Oreochromis sp.

Mexican researchers evaluated the antioxidant properties of collagen extracted from the skin and gall of Oreochromis sp., also known as red tilapia. Their findings were published in the Journal of Medicinal Food.

• Not much focus is given to the reduction of fishing waste generated during evisceration and filleting.
• On the other hand, fishing waste is used in the production of flours and silages, which are low value-added products.
• Because it poses a serious environmental problem, the researchers decided to look for an alternative and profitable use for fishing waste.
• To analyze its antioxidant properties, they subjected the skin and gall of red tilapia to three treatments and obtained salt-soluble collagen, acid-soluble collagen (ASC) and pepsin-hydrolyzed collagen (PHC).
• They then measured collagen yield and antioxidant activity for both hydrolyzed (HC) and non-hydrolyzed collagen (PHC).
• The researchers reported that ASC from tilapia skin had the highest extraction yield (3.02 percent), while only PHC extraction (0.16 percent) was feasible for tilapia gall.
• NHC did not display antioxidant activity, but ASC from skin and PHC from gall showed a 22.58 percent and 10.34 percent radical scavenging activity (RSA) against DPPH, respectively.
• Against the free radical ABTS, PHC from tilapia skin and gall exhibited an RSA of 30.40 percent and 29.43 percent, respectively.
• Meanwhile, ASC from skin and PHC from gall exhibited 94.40 percent and 81.54 percent ferric-reducing antioxidant power, respectively, and 43.63 and 38.08?mcg ascorbic acid equivalent [AAE]/mL total antioxidant capacity, respectively.
• While HC extracts showed RSA, NHCs proved to be excellent metal ion chelators.

Based on these findings, the researchers concluded that red tilapia skin collagen can be used as an active ingredient in nutraceuticals, pharmaceuticals and functional foods.

Journal Reference:

Medina-Medrano JR, Quinones-Munoz TA, Arce-Ortiz A, Torruco-Uco JG, Hernandez-Marinez R, Lizardi-Jimenez MA, Varela-Santos E. ANTIOXIDANT ACTIVITY OF COLLAGEN EXTRACTS OBTAINED FROM THE SKIN AND GILLS OF OREOCHROMIS SP. Journal of Medicinal Food. 10 July 2019;22(7):722–728. DOI: 10.1089/jmf.2019.0013