Isolation and screening of cyanobacteria native to the Segzi Desert from soils covered with terrestrial lichens

Desert terrestrial lichens are often from the cyanolichens category, which has achieved a wide range of adaptation to ecological conditions. To cultivate and screen the native desert cyanobacteria, samples were collected from the soils covered with cyanolichens, including Pecania terricola, Enchylium tenax, Collema cocophorum, and Lathagrium auriforme. After culturing the cyanobacteria on the BG 11 medium, homogeneous cyanobacteria were prepared in four purification steps and screened based on the amount of chlorophyll a and polysaccharides (LB EPS and TB EPS). Based on morphological characteristics, cyanobacteria species, including Coleofasciculus chthonoplast and Microcoleus vaginatus, were identified. According to the results, the amount of chlorophyll-a in Microcoleus vaginatus was 0.49 mg / l, LB-EPS was 17.55%, and TB-EPS was 8.45%. In Coleofasciculus chthonoplast chlorophyll a, LB-EPS and TB-EPS were measured 0.27 mg /L, 16.36% 8.22%, respectively. The results of the ANOVA test showed that the difference between chlorophyll a and EPS in the two species of cyanobacteria was significant. The mean concentration of intracellular polysaccharides was not significantly different from each other. Based on these results, Microcoleus vaginatus had better physiological conditions and higher adaptation to the ecological stress compared to Coleofasciculus chthonoplast. Therefore that is a more suitable species for soil stabilization in the Sejzi desert.