AComDim highlighting of agroclimatic factors influencing the Moringa oleifera Lam. leaf’s composition

International audienceThe quality control of the chemical composition leaves of Moringa oleifera Lam. is fundamental for the dietary treatment of diseases or for any quantitative study on human nutrition. To highlight the impact of climatic and edaphic factors on the chemical composition of Moringa oleifera Lam. leaves, a multivariate chemometric method, ANOVA (ANalysis Of Variance) Common Dimensions (AComDim) was used to interpret the changes in their Fourier Transform Infrared Attenuated Total Reflectance (FTIR-ATR) spectra. Leaves were collected from five geographical areas of Cameroon, recognized for their climatic and soil diversity. The factor “agroclimatic zone” was the most significant, followed by “month/year” (January, April and September between 2015 and 2017), “year” and “maturity” factors. Three slightly significant interactions between “year” and “agroclimatic zone” or “maturity” or “month/year” were observed. For a given agroclimatic zone, January samples were richer in polysaccharides than April samples which were characterized by a highest amount in proteins and aromatic compounds. The “maturity” factor revealed that young leaves contained fewer proteins and antioxidant compounds. The “year” factor was involved in all significant interactions and confirmed the temporal character of the studied factors. The diversity of climate and soils in Cameroon must be taken into account if a certain typicity of collected Moringa Oleifera leaves, or a constant quality may be assured before their marketing phase in powder form as a dietary supplement