Comparative Study on some Plants as Sources of Natural Antioxidants

Abstract

Nowadays, plants and natural products have a great probable interest due to their pharmaceutical, cosmetic and nutritional applications. So, the biologically active compounds of moringa and fig leaves as well as red pepper fruits and seeds were assessed as antioxidants agents as well as their antioxidant activities were evaluated using different assays and the obtained results revealed that, moringa and fig leaves had the highest content of chlorophylls A and B, but their contents in moringa leaves (625.37 and 229.94 mg/100g, respectively) were more than four folds greater than fig leaves (142.14 and 83.57 mg/100g, respectively). Red pepper fruits and moringa leaves had the highest contents of total carotenoids. The ABTS and DPPH procedures gave the highest antioxidant capacity values of all selected raw materials. Furthermore, moringa and fig leaves recorded the highest contents of antioxidant activity comparing with red pepper fruits and seeds correlated with the highly contents of total phenols and flavonoids. Moringa leaves had higher contents of phenolic acids (309.4mg/100g) than other selected plants and E-vanillic and pyrogallol were the most common phenolic compounds found in moringa leaves. On the other hand, there are little differences between fig leaves and red pepper fruits but, the lowest phenolic acids content (136.58 mg/100g) was detected in red pepper seeds. There was variation in flavonoids individuals between all selected raw materials. Moringa and fig leaves had approximately the same highest contents of flavonoids (283.71 and 266.73 mg/100g, respectively) than red pepper fruits and seeds which recorded lowest ones (112.84 mg/100g). Cobalamin (B 12) was the major B complex vitamins found in fig leaves, red pepper fruits, moringa leaves and red pepper seeds which recorded 994.01, 217.46, 164.81 and 125.5 mg/100g, respectively. Moringa leaves and red pepper fruits are considered as excellent sources for vitamins C and K that play an important roles as antioxidant agents to protect biological systems via inhibition or prevention of oxidation stress induced by reactive oxygen substances generated from normal metabolic activity or environmental factors followed by red pepper seeds and fig leaves.