Morphological and Genetical Characterization of Selected Cyanobacterial species from Lesser Cholistan and their Potentials

Abstract

The objectives of this study were to explore and collect cyanobacterial samples from different substrates and localities in the lesser Cholistan desert; characterize the isolates morphologically and genetically using the polyphasic approach; and assess the antibacterial, cytotoxic and anticancer potential. For this purpose expeditions were commissioned to Cholistan desert. In the field ecological data was recorded and collated with lab-based morphological and molecular analyses to infer species identification and diversity. This involved culturing of several species too. Axenic cultures obtained in BBM, BG11, BG0 and SpM media, corresponding to seven major taxa of Cyanobacteria, were recorded. Among field samples, the green types were observed frequently contributing a share of 48.5% while 37% blue green types were observed in the collections. Among green algal types, members of the genus Scenedesmus were found most frequently. Other green taxa were represented by either one or two species only. Among blue green types, Phormidium was observed most frequent. Among unique types, Neowestiellopsis was found at three sites. Anabaena was observed on sites found in close vicinity of agricultural land. In conclusion, Cholistan desert has huge cyanobacterial diversity including the unicellular forms; the polyphasic approach has clarified the identification/taxonomic position of morphologically closely related species. This included Nodularia, Desertifilum, Neowestilliopsis and Nostoc sp. with subtle morphological differences. For the first time, four genera Neowestilliopsis, Desertifilum, Klisinema, and Aliinostoc were reported from the Cholistan Desert, Pakistan. The biological activity analyses revealed strong antimicrobial, cytotoxic and anticancer potential in Neowestiellopsis, Tolypothrix and Desertifilum, and all these warrant further analyses.