Soil properties and phytochemical analysis of spleen amaranth (Amaranthus dubius Mart. Ex Thell.) from Ankole and Teso sub-regions of Uganda: Implications for management and prevention of hyperglycemia

Abstract

Background: The current authors reported a remarkably higher prevalence of hyperglycemia in Ankole than in the Teso sub-region of Uganda, and Amaranthus dubius was documented among the frequently eaten leafy vegetables in both sub-regions. In an attempt to investigate this remarkable variance in the prevalence of hyperglycemia and find alternative therapies for hyperglycemia, we assessed the influence of soil properties on phytochemical quantity in spleen amaranth (A. dubius) from the two sub-regions. The soil properties and vegetable phytochemicals were quantified using spectrophotometric methods. Results: Soil pH, organic matter (OM), and nitrogen (N) were higher in soil samples from the Teso sub-region than those from the Ankole sub-region. The Teso sub-region had sandy loam soils that were relatively low in exchangeable cations, whereas Ankole had clay loam soils. Total tannin content (TTC) and total saponin content (TSC) were significantly higher in A. dubius samples from the Teso sub-region, and total alkaloid content (TAC) was higher in vegetable samples from Ankole. The Pearson’s correlation results showed a significant relationship between pH and TTC, N, and TAC. Total flavonoid con tent (TFC) was correlated with exchangeable cations. Conclusion: High soil pH, N, cations, and sand percentage found in soil samples from the Teso sub-region supported the biosynthesis of polyphenolic compounds in the vegetable samples. By implication, this consequently benefited its consumers by reducing blood glucose levels ultimately reducing the prevalence of hyperglycemia in the region.