Polyphasic evaluation and cytotoxic investigation of isolated cyanobacteria with an emphasis on potent activities of a Scytonema strain

Trang T Ngo; Bich-Loan T Nguyen; Tuan A Duong; Thu-Huyen T Nguyen; Thanh L Nguyen; Kien T Kieu; Minh-Hanh T Do; Sang V Nguyen; Nguyen Dinh Thang; Hang T L Pham

doi:10.3389/fmicb.2022.1025755

Polyphasic evaluation and cytotoxic investigation of isolated cyanobacteria with an emphasis on potent activities of a Scytonema strain

Front Microbiol. 2022 Oct 28:13:1025755. doi: 10.3389/fmicb.2022.1025755. eCollection 2022.

Authors

Trang T Ngo¹, Bich-Loan T Nguyen¹, Tuan A Duong², Thu-Huyen T Nguyen³, Thanh L Nguyen^{1

3}, Kien T Kieu³, Minh-Hanh T Do¹, Sang V Nguyen^{1

3}, Nguyen Dinh Thang¹, Hang T L Pham^{1

4}

Affiliations

¹ Faculty of Biology, University of Science, Vietnam National University, Hanoi, Vietnam.
² Department of Biochemistry, Genetics, and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, South Africa.
³ Center for Life Sciences Research, Faculty of Biology, University of Science, Vietnam National University, Hanoi, Vietnam.
⁴ The Key Laboratory of Enzyme and Protein Technology, University of Science, Vietnam National University, Hanoi, Vietnam.

Abstract

Cyanobacteria are phototrophic organisms widely found in most types of natural habitats in the tropical regions of the world. In this study, we isolated and identified cyanobacterial strains from paddy soil in Hanoi (Vietnam) and investigated their cytotoxic activities. Five isolated cyanobacterial strains showed distinctive profiles of gene sequences (rRNA 16S and rbcL), phylogenetic placements, and morphological characteristics. Based on the polyphasic evaluation, they were classified as Scytonema bilaspurense NK13, Hapalosiphon welwitschii MD2411, Aulosira sp. XN1103, Desikacharya sp. NS2000, and Desmonostoc sp. NK1813. The cytotoxic screening revealed that the extract of strain Scytonema bilaspurense NK13 exhibited potent cytotoxic activities against four human cell lines of HeLa cells, OVCAR-8 cells, HaCaT cells, and HEK-293T cells, with IC₅₀ values of 3.8, 34.2, 21.6, and 0.6 μg/mL, respectively. This is the first time a well-classified Scytonema strain from tropical habitat in Southeast Asia has been recognized as a potential producer of cytotoxic compounds.

Keywords: Aulosira; Desikacharya; Desmonostoc; Hapalosiphon; Scytonema; polyphasic approach.