Biodegradation of crude oil by some cyanobacteria under heterotrophic conditions

Abstract

AbstractPetroleum hydrocarbons are one of the most common groups of persistent organic contaminants in the environment. The degradation process of the oil takes place by microorganisms to remove it from the environment. The cyanobacteria Nostoc punctiforme and Spirulina platensis are used in this study to investigate their ability to grow and degrade different concentrations of crude oil under heterotrophic conditions. It was found that S. platensis can grow at different concentrations of crude oil (0.5, 1, 1.5, and 2%). No growth was obtained with N. punctiforme incubated with crude oil concentrations (0.5, 1, 1.5, and 2%) until 11 days, after this period the growth progressively increased, especially with 2% crude oil. Chlorophyll a, contents of S. platensis, decreased with increasing incubation period and approximately unchanged with increasing concentration of crude oil. High carotenoids contents in S. platensis was obtained after 7 and 11 days of incubation with different concentrations of oil except...