Bioremediation of heavy metals from municipal sewage by cyanobacteria and its effects on growth and some metabolites of Beta vulgaris

The present research was done to study the ability of cyanobacterial species for removing heavy metals from sewage. As well, to estimate the growth and some metabolites of Beta vulgaris irrigated with sewage treated by cyanobacterial species. The best removal results were obtained by Anabaena oryzae compared to the other studied cyanobacteria. Whereas A. oryzae showed high removal efficiency for cadmium (Cd2+) followed by lead (Pb2+), zinc (Zn2+), iron (Fe2+), copper (Cu2+) and manganese (Mn2+) (88.5, 83.1, 68.8, 62.0, 55.2 and 42.4%, respectively). Irrigation of plants by untreated or treated sewage generally caused stimulation in the total proteins, proline, carbohydrates and ascorbic acid. B. vulgaris grown in soil irrigated with untreated sewage showed maximum catalase, peroxidase activity, hydrogen peroxide (H2O2) and lipid peroxidation compared to the other treatments. The heavy metals availability was relatively low in the plant irrigated with treated sewage by cyanobacterial species, so the antioxidants requirement was low and hence the induction of antioxidants was lower compared to the plant irrigated with untreated sewage.