Determination of Vitamin Contents of Maize (Zea mays L) Produced and Stocked from Rural Conditions in Cote D’ivoire

Abstract

Aims: Maize is prized for its richness in nutrient compounds. Despite its socio-economic importance, maize faces a quality problem that is sometimes very delicate. Indeed, maize during different production, post-harvest processing, storage and transport conditions is exposed to bio-aggressors that can alter the quality of this cereal. With this in mind, this study was conducted to determinate the vitamins contents of maize produced and stored in five maize-producing regions of Côte d’Ivoire. Study Design: A total of 1 500 samples of maize as grains, epis and spathes were collected at rate of 500 samples by region (Gbêkê, Poro, Hambol, Indénié-Djuablin and Gontougo) and sent to the laboratory for analysis of the vitamin contents. Place and Duration of Study: This study was carried out during March 2016 to January 2017. Then, the analyses of the collected sample took place at the Biotechnology, Agriculture and Valorisation of Biological Ressources Laboratory of the Félix Houphouët-Boigny’s University, Abidjan. Methodology: Vitamins determination was carried by High Performance Liquid Chromatography. A total of twelve vitamins were evaluated namely 9 water-soluble vitamins (thiamin, riboflavin, niacin, choline, pantothenic acid, pyridoxine, biotin, folic acid and cobalamin) and 3 fat-soluble vitamins (β-carotene, vitamin E and K). Results: Results show a significant difference between vitamins contents of the different maize forms and regions. The mean values ranged from 0.09 ± 0.04 to 557.24 ± 10.97 mg / kg for water-soluble vitamins and from 0.31±0.25 to 4.20±1.00 mg / kg for fat-soluble vitamins. Choline was the most abundant of the water-soluble vitamins while β-carotene and vitamin E were the most abundant of the fat-soluble vitamins. Maize grains and epis had the highest levels of these vitamins all of the regions. Maize spathes samples, especially those from Indénié-Djuablin and Gontougo, showed the lowest concentrations. Conclusion: A significant variability from one region to another can be noticed at level of vitamins regardless the type of maize. Maize vitamin contents seem to be related to maize form (grains, epis, spathes), maize variety, agronomic practices, post-harvest treatments and storage structure.