Pharmacognosic researches on isolated microalgal species from geothermal springs of Afyonkarahisar province

Microalgae are one of the oldest life forms in the universe. Microalgae based compounds show antioxidant, anticancer, antiinflammatory, antiobesity, antiangiogenic, anti HIV, antiviral, antiparasitic, antimicrobial, neuroprotective, antifungal and enzyme inhibitory effects. Cyanobacteria, which is a class of microalgae, are one of the important group of organisms for the discovery of biologically active new compounds. In our thesis work, four cyanobacteriae were isolated from three different geothermal springs of Afyonkarahisar province and they were identified with 16S ribosomal RNA analysis. It was found that isolated species are Geitlerinema sp., Oscillatoria sp., Leptolyngbya sp. (a) and Leptolyngbya sp. (b). Cyanobacteriae were cultured and hexane extracts were used to determine of their carotenoid profiles as well as antioxidant and cytotoxic effects. C-phycocyanins were purified from aqueous extracts of four dry cyanobacteria masses and their antioxidant and cytotoxic effects were determined. For determining antioxidant effects, DPPH and ABTS radical scavenging methods were used. MTT method was used to determine cytotoxic effect against to HeLa cancer cell and L929 healthy cell lines. Isolated Leptolyngbya sp. (a) shows higher content of β-carotene and C-phycocyanin; besides carotenoids and C-phycocyanin's of this cyanobacteria show higher capacity to scavenge DPPH and ABTS radicals among other isolated species. Cyctotoxic effect results show neither carotenoids nor C-phycocyanins posses significant cytotoxic effect to HeLa and L929 cell lines. Results were compared with the similar researches on Spirulina species which is leading cyanobacteria for biotechnologic and commercial applications all over the world. Our thesis work is an important study in terms of determination of native species, that can be alternative to Spirulina which is widely used in industries such as health, food and cosmetics in the world, with their carotenoid and phycocyanin content and revealing bioactivity of their compounds. Keywords: Leptolyngbya sp., cyanobacteria, carotenoid, C-phycocyanin, UPC2.