Mango Peels and Kernels from Selected Varieties of Côte d’ivoire are Potential Sources of Antioxidative Bioactive Compounds

Abstract

Aims: This study aimed to quantify the bioactive compounds and the antioxidant activity of mango peels and kernels from two main varieties (Kent, Keitt) cultivated in Côte d’Ivoire.
 Study Design: Processing of mango varieties, determination of bioactive compounds content of mango peels and kernels, evaluation of antioxidant activity of mango peels and kernels.
 Place and Duration of Study: Felix Houphouet-Boigny University, Biotechnology Laboratory (March to September 2019).
 Methodology: Ripe mango (Mangifera indica L) fruits from Kent and Keitt varieties were processed to obtain peels and kernels powders. Methanolic extracts of peels and kernels were used to determine the content of phenolics, flavonoids and tanins while hexanic extracts were used to determine the content of carotenoids and phytosterols. DPPH scavenging and ferric reducing power tests were used to evaluate antioxidant activity of peels and kernels.
 Results: Total phenolics content of kernels of Kent (4371.22 ± 24.98 mg/100g dw) and Keitt (4037.93 ± 20.43 mg/100g dw) were higher (P ˂ 0.05) than those of peels from the two varieties (2564.37 – 3082.07 mg/100g dw). The values for carotenoids content of peels varied from 37.53 to 57.74 μg/g dw while those of kernels varied from 1.48 to 3.46 μg/g dw. Based on DPPH test The IC50 values ranged from 0.2 to 0.7 mg/mL with the highest antioxidant activity reported for kernels from Kent variety. The absorbance at 700 nm was found to be 0.4 for kernel of Keitt variety and 0.3 for ascorbic acid at a dose level of 0.03 mg/mL.
 Conclusion: Peels and kernels from Kent and Keitt varieties are potential sources of bioactive compounds especially phenolics, tanins, carotenoids and phytosterols. These valuable bioactive compounds in mango by-products may have greater application in the food, cosmetic and pharmaceutical industries.