Regrowth age, region, and harvest season on chemical and color parameters of Moringa oleifera from Brazil

Abstract

Moringa oleifera leaves are used in Brazilian folk medicine for their nutritional and biological activities. Although already cultivated for commercial ends in warmer regions of Brazil, little is known about the effects of seasonality, growing region, and regrowth age. This study evaluated, by chemometric tools, the influence of harvest season (winter, spring, autumn, and summer), growing area in Brazil (South, Southeast, and Northeast), and regrowth age (40 and 80 days) on chemical and color parameters. The chemical composition was determined according to AOAC methods; the color measurement and the elemental composition were performed using colorimetry and spectrophotometry, respectively. All tests were carried out at UTFPR laboratories. The results from Multivariate Analysis of Variance (Manova) revealed that all the parameters evaluated were affected by seasonality, regrowth age, and growing region. Principal component analysis (PCA) was carried out to better understand how the Moringa leaf samples correlate with response variables, and PCA found two distinct groups. The color of the M. oleifera leaves was affected by seasonality, regrowth, and region of cultivation, and samples from the south region were greener than the two other seasons. Leaves with 40 days of regrowth from the south were characterized by their high protein content (25.2%) and potassium content (1646.8 mg 100 g−1). At the same time, young leaves cultivated in the southeast showed a higher content of fiber and lipid content. Finally, samples from the northeast harvested during autumn, spring, and summer showed a higher content of ash and minerals: Mg, Mn, and Na. Samples for the northeast showed a good correlation with temperature and radiation, which indicates that these parameters can influence the nutritional quality of M. oleifera leaves.