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This study assessed the antioxidant activity of M oringa oleifera Lam. extracts on the oxidative stability of fish oil subjected to conditions of accelerate storage (16 days at 60C) compared with synthetic antioxidants such as tertiary butylhydroquinone ( TBHQ) and butylated hydroxytoluene ( BHT). Fish oil samples were added with leaves, flowers and seed pod extracts and evaluated for peroxide, hydroperoxides, anisidine and conjugated diene values. Changes in trans-fatty acid and aldehyde content were also assessed. The addition of M oringa extracts delayed the oxidation of fish oil; in particular, extracts of leaves showed a higher antioxidant activity when compared with TBHQ and BHT, considering peroxide and hydroperoxide levels. To control the formation of secondary oxidation compounds, synthetic antioxidants were most effective; however, leaf extract showed the highest protective effects of polyunsaturated fatty content in fish oil. Results indicate that the extract of M . oleifera leaves is an effective antioxidant to prevent oxidation in fish oil. Practical Applications Antioxidants are important ingredients in food processing to retard, reduce or prevent oxidative deterioration. Synthetic antioxidants are widely used in the food industry; however, their utilization has been questioned because of toxicity. Therefore, there is a growing interest in the use of natural antioxidants to reduce or replace the synthetic antioxidants in edible oils. M oringa oleifera L. is a botanical specie that is well known for its rich compounds with high antioxidant activity; in particular, its leaf extract can be used to replace synthetic antioxidants used in fish oil. [ABSTRACT FROM AUTHOR]

Co-products from the juice processing of guava (CG), mango (CM) and barbados cherry (CB) were investigated with a view to their exploitation as a potential source of natural antioxidants. The ethanolic extracts were analyzed for total extractable phenolic content (TEP), DPPH radical scavenging activity (RSA-DPPH), ferric reducing antioxidant power (FRAP) and antioxidant activity in relation to the β-carotene/ linoleic acid system. The TEP levels in the CG, CM and CB extracts were (24.15 ± 1.59), (44.18 ± 1.73) and (49.21 ± 3.70) mg GAE/g extract, respectively. The CM extract showed higher DPPH, FRAP and antioxidant activity in the β-carotene/linoleic acid system. The data revealed a positive linear correlation between TEP, RSA-DPPH and FRAP (r2 = 0.85 - 0.98); however, the β-carotene/linoleic acid system (r2 = 0.01 - 0.26) shows low correlation with the TEP levels and other assessment systems. The results suggest that co-products generated from the juice processing of the studied fruit have promising use as a natural source of antioxidants. [ABSTRACT FROM AUTHOR]