Crude oil-induced morphological and physiological responses in cyanobacterium Microchaete tenera ISC13

In this research the effects of crude oil on morphological and physiological characterization of the cyanobacterium Microchaete tenera ISC13 were investigated. Isolated cyanobacterium treated with different oil concentrations [control, 1, 2.5, 5 and 7%] in carbonless BG11[0] medium. Morphological characteristics such as morphology of filament, cellular shapes and sizes, relative position of heterocytes and akinetes were described for these treatments. Biometrical and morphological observations carried out by light and scanning electron microscopy. Dimensions of cells did not significantly impress, although a slightly increase in length of vegetative cells was observed in 2.5 and 5% crude oil in comparison to control. With respect to the physiological responses, cyanobacterium growth increased with elevated oil concentration but no changes was observed in chlorophyll content. Phycobiliproteins [PBP], phycocyanin [PC] and allophycocyanin [APC] had the highest rate in control. Increasing crude oil decreased all PBP. This study demonstrated that crude oil doesn't have destructive effect on Microchaete tenera ISC13 and suggest probable potential of this microorganism to use oil hydrocarbons as carbon source

Molecular and morphological characterization of oil polluted microalgae

Oil pollutions are widespread environmental pollutants. Most of the studies have been focused on the biodegradation of these pollutions. Unfortunately, the information on the microflore of the polluted regions especially for microalgae is limited. In this research, we have focused on Masjed Soleiman; one of the most oil polluted cities in Iran. Soil and water samples were collected from different stations and seasons and their microalgae identified morphologically and molecularly. TPH, PAH and heavy metals of these stations were analyzed. The relationship between TPH contents and micro algal populations has also been considered. Results showed microalgae, present in these regions belonged to Cyanobacteria, Chlorophyta and Diatoms. Among them Phormidium sp. was the most dominant species that was found in all polluted regions. Microalgae biomass, declined in high level polluted medium, whereas low levels of TPH showed no effect on microbial biomass. According to the results the isolated specimens have high resistance to environmental pollutions. So the type and frequency of the species, can lead us to estimate the amount of pollution in different sampling regions