Background: Vernonia amygdalina is a green leafy vegetable that grows in tropical Africa and popularly cultivated in the southern part of Nigeria for its economic, nutritional and ethnomedicine value.Aims: This study analysed the influence of copper-induced abiotic stress on the deoxyribonucleic acid and secondary metabolites of V. amygdalina.Setting: Analyses of plant material were carried out in the Department of Botany, Lagos State University.Methods: Deoxyribonucleic acid (DNA) extraction and Inter Simple Sequence Repeat (ISSR) amplification were performed. Copper (Cu) concentration in leaves and stem of V. amygdalina was determined using inductively coupled plasma-optical emission spectroscopy (ICP-OES), secondary metabolites were determined using gas chromatography–mass spectrometry (GC-MS) and the effect on DNA amplification and profiling was analysed using gel electrophoresis.Results: After 41 days of cultivation, the stem of V. amygdalina significantly bioaccumulated 37 mg/L, 50 mg/L and 215 mg/L of Cu after spiking with 400 mg/L, 1000 mg/L and 2000 mg/L, respectively, whilst the leaves accumulated 52 mg/L, 100 mg/L and 350 mg/L of Cu, respectively. Copper-impregnated soil influenced phytochemicals of the plants by causing inconsistent increase and decrease in specific compounds such as levomenthol, methyl stearate and glycerine. Deoxyribonucleic acid bands of the stem and leaf of V. amygdalina from control site showed no band shift, whilst band shift occurred in the stem and leaf of the Cu-spiked V. amygdalina.Conclusion: This study revealed the leaves of V. amygdalina having higher Cu accumulation capacity than the stems. Also, Cu alters the quality and quantity of phytochemicals in plant parts.

Introduction: Anthropogenic activities by man in Nigeria especially Lagos State have induced accumulation of heavy metals in soils which invariably have resulted in the disturbance of living organism’s biochemical and physiological functions. Aim: This study assessed the level of heavy metals concentration in cassava (Manihot esculenta) harvested in selected farms in Lagos state. Materials and Methods: Leaves, stems, tubers of cassava were obtained from Morogbo, Badagry area and Odogunyan, Ikorodu area; and the concentrations of heavy metals content were determined using Atomic Absorption Spectrophotometric (AAS) method. Results: The results in mg/kg showed that heavy metals concentration [Nickel (3559.67 ± 5794.16), Manganese (120.33 ± 5.51), Copper (52.10 ± 2.85 and so on] were highly bioaccumulated in leafy part of the cassava. Conversely, Sodium (11620.00 ± 820.18) and Potassium (15133.33 ± 508.46) were highly bio-accumulated in the cassava’s stem while Calcium (3996.67 + 35.12) was found in high concentration in the cassava’s tuber. Lead (0.03 ± 0.05) and Cadmium (0.08 ± 0.08) were of significant values in the soil of Ikorodu and lower in the soil of Badagry. Heavy metal (Ni, Mn, Cd, Mg and Na) bio-accumulation in the two different location were higher in Badagry than Ikorodu, while Zn, Fe and K were higher in Ikorodu than in Badagry but Cobalt was not detected in both sites. Conclusion: Copper, Lead, Zinc, Manganese, Iron, Nickel, Calcium, Sodium and Potassium were above the recommended level of W.H.O. Therefore, consumption of leafy and tuber part of the cassava in both Ikorodu and Badagry areas could pose threat to animals.