Variations in the accumulation of three secondary metabolites in Euclea undulata Thunb. var. myrtina as a function of seasonal changes

Results for the summer rainfall area indicate seasonal fluctuations in the levels of α-amyrin-3O-β-(5-hydroxy) ferulic acid in roots. It is also noteworthy that the roots always contain 7-methyl-juglone and only found in the leaves on the rainy season of the summer rainfall area. The stems can be harvested for α-amyrin-3O-β-(5-hydroxy) ferulic acid and the leaves for epicatechin in both seasons in the summer rainfall area. Results from the winter rainfall area indicate far less seasonal fluctuation. Most metabolites appear to be either present or absent in the respective organs regardless of season with the exception of epicatechin that is absent in the roots in the rainy season. Fluctuations were, however, detected in epicatechin levels in stems and 7-methyl-juglone levels in roots. From the results obtained it is evident that α-amyrin-3O-β-(5-hydroxy) ferulic acid occurs in roots, stems and leaves in the winter rainfall area and is independent of temperature whereas 7-methyl-juglone is present only in the roots. Leaves can replace the use of roots when harvested in a winter rainfall area irrespective of season as α-amyrin-3O-β-(5-hydroxy) ferulic acid and epicatechin are present and 7-methyl-juglone are absent.