Bioactives and Antimicobial Potential of Processing by Products of Four Mango Varieties (Magifera indica Varieties Amelie, Kent, Keitt and Brooks) from the Poro Region (Ivory Coast)

Abstract

Aims: During the industrial processing of mango, considerable quantities of peel and seeds are rejected, which results in a significant economic loss for the manufacturer, as well as an impact on the environment. However, mango almond and peel flours present enormous nutritional and especially therapeutic potentialities. Thus, the objective of this work is to contribute to the valorization of the waste of 4 varieties of mango (Amelie, Kent, Keitt, Brooks) from north in Ivory Coast by the determination of their bioactive compounds in, order to be used in the pharmaceutical industry. Place and Duration of Study: Laboratory of Biochemistry and Food Technology, Nangui Abrogoua University, Abidjan 02, Ivory Coast. Between March 2019 to July 2021.  Methodology: Phenolic compounds of the Mango almond and peel flours were extracted with ethanol. UV-VIS spectrophotometry was employed to further quantify the total phenolic, tannin and total flavonoid content. DPPH radical scavenging assay, 2.2-azino-bis (3-ethylbenzthiazoline-6- sulphonic acid (ABTS) scavenging test and ferric reducing antioxidant power (FRAP) were used to determine antioxidant activity. As for phenolic acids, they were analysed by HPLC. Well diffusion method was used to determine antibacterial activity. Results: The analysis of the bioactive compounds of these mango discards revealed that they are characterised by high contents of total polyphenols 39.67 ± 0.04 to 85.18 ± 0.01 mg/g in the peel and 22.86 ± 0.03 to 58.43 ± 0.00 mg/g in the almond, flavonoids 4.36 ± 0.03 to 20.43 ± 0.02 mg/g in peel and from 6.59 ± 0.01 to 26.72 ± 0.02 mg/g in almonds, tannins 5.04 ± 1.13 to 8.64 ± 0.76 mg/g in peel and from 6.58 ± 0.06 to 12.46 ± 0.11 in almonds. Antioxidant activity varies in peel and almond from 64.49 ± 2.56 to 96.40 ± 0.32 % and 89.16 ± 1.45 to 97.96 ± 0.25 % respectively for ABTS, from 59.51 ± 0.26 to 86, 27 ± 0.56% and 80.39 ± 0.56 to 87.21 ± 0.39% for DPPH inhibition and from 0.59 ± 0.0 to 0.72 ± 0.01 mg/g and from 0.81% to 0.92% mg/g for iron reduction by the FRAP method. As for the antimicrobial activity, very marked inhibition diameters were observed both with the peel extracts and in the almonds for different bacteria (B. ceurus, E. coli, ST. aureus, S. typhi, P. aeruginosa). Conclusion: These results demonstrate that the antimicrobial and antioxidant activities of the by-products of the four mango varieties are potential sources of bioactive compounds. These by-products could therefore be used in the pharmaceutical industry and diet.