biodiversity of cultivable green algae collected from the coast of guilan

In this study, the cultivable algae in the coasts of guilan province in the south west part of the caspian sea were isolated, purified and then morphologically and molecularly identified in february 2016. the separated samples were examined by optical microscopy and morphological analysis. then, 18s rdna gene primer pair was used for green algae polymerase chain reaction. totally, 14 algae strains were identified. among them, four strains were related to the algal branch of chlorophyta. considering the importance of the caspian sea as one of the largest aquatic habitats in the country, many studies have been conducted on the identification and study of phytoplankton and algae of the caspian sea. the seasonal variation of phytoplanktons in the southern basin of the caspian sea was studied. during a winter season, 31 species belonged to the chlorophyta among 32 study stations. the results of this research show that the growth and diversity of the algae in the habitats is affected by seasonal fluctuations and changes in environmental factors such as temperature, salinity, food level, type of bed (due to spread range of sampling area) and a combination of them. in general, research has shown that some factors such as salinity, temperature, source of nitrogen and ambient oxygen, ph, heavy elements, uv rays and other environmental stressors affect the chemical composition and antioxidant activity in algae.