Ethanolics extracts of Moringa: Antioxidant effect in soybean oil by PDSC and Rancimat

• Published in: Journal of thermal analysis and calorimetry 2014-07, Vol.117 (1), p.265-268
• Main Authors: Nascimento, Jaqueline A., Araújo, Kassandra L. G. V., Epaminondas, Poliana S., Pontes, Alline L. S., Souza, Antonia L., Queiroz, Neide, Souza, Antonio G.
• Format: Article
• Language: English
• Subjects: Analysis; Analytical Chemistry; Antioxidants; Chemistry; Chemistry and Materials Science; Inorganic Chemistry; Measurement Science and Instrumentation; Physical Chemistry; Polymer Sciences
• ISSN: 1388-6150; 1588-2926
• DOI: 10.1007/s10973-014-3664-z

The use of natural antioxidants has been widely promoted in the food industry, because it is economically viable and very attractive with consumers. In this study, we determined the extractable total phenolic content (FET) of crude ethanol extracts of the leaves (EL), flowers, and seed pods of Moringa oleifera Lam. We also evaluated the antioxidant effect of the extracts on oxidative stability of soybean oil, through the accelerated PDSC and Rancimat ® techniques using the synthetic antioxidants butylated hydroxytoluene (BHT) and tert -butylhydroquinone (TBHQ) as positive control. The values of FET in the extracts ranged from 41.75 ± 3.35 to 53.69 ± 1.00 mg GAE g −1 , and EL extract exhibited best result. The results of oxidative stability in both techniques showed that the EL extract provided greater protection to the oil, indicating a correlation between the amount of FET and the protective effect. Comparison made between the synthetic antioxidants and extracts revealed that in the Rancimat technique, extracts were less effective than the synthetic antioxidants TBHQ and BHT, however, in the PDSC technique the EL extract was more effective than BHT, proving to be a good alternative for applications in the soybean oil, replacing this synthetic antioxidant.