title: Assessing contamination of microalgal astaxanthin producer Haematococcus cultures with high-resolution melting curve analysis.
abstract: Due to its superior antioxidant capabilities and higher activity than other carotenoids, astaxanthin is used widely in the nutraceutical and medicine industries. The most prolific natural producer of astaxanthin is the unicellular green microalga Haematococcus pluvialis. The correct identification of any contaminants in H. pluvialis cultures is both essential and nontrivial for several reasons. Firstly, while it is possible to distinguish the main microalgal contaminant Coelastrella sp. (in H. pluvialis cultures), in practice, it is frequently a daunting and error-prone task for personnel without extensive experience in the microscopic identification of algal species. Secondly, the undetected contaminants may decrease or stop production of astaxanthin. Lastly, the presence of other contaminants such as fungi can eventually infect and destroy the whole algae collection. In this study, high-resolution melting (HRM) analysis was developed to detect microalgal and fungal contamination. The developed diagnostic procedure allowed to distinguish pure H. pluvialis samples from cultures contaminated with low amounts (1.25 ng/ml) of microalgal DNA and fungal DNA (2.5 ng/ml). Such discrimination is not possible with the use of microscopy observations and allows fast and efficient collection testing.
authors.affiliation: Functional Evolution of Biological Systems Team, Institute of Plant Genetics, Polish Academy of Sciences, Strzeszynska 34, 60-479, Poznan, Poland. adaw@igr.poznan.pl.
authors.forename: Adam
authors.initials: A
authors.lastname: Dawidziuk
authors.affiliation: Functional Evolution of Biological Systems Team, Institute of Plant Genetics, Polish Academy of Sciences, Strzeszynska 34, 60-479, Poznan, Poland.
authors.forename: Delfina
authors.initials: D
authors.lastname: Popiel
authors.affiliation: AlgaeLabs Ltd., Dunska 9, 54-427, Wroclaw, Poland.
authors.forename: Magda
authors.initials: M
authors.lastname: Luboinska
authors.affiliation: AlgaeLabs Ltd., Dunska 9, 54-427, Wroclaw, Poland.|Institute of Chemistry of Food Technology, University of Economics, Komandorska 118/120, 53-345, Wroclaw, Poland.
authors.forename: Michal
authors.initials: M
authors.lastname: Grzebyk
authors.affiliation: AlgaeLabs Ltd., Dunska 9, 54-427, Wroclaw, Poland.
authors.forename: Maciej
authors.initials: M
authors.lastname: Wisniewski
authors.affiliation: Functional Evolution of Biological Systems Team, Institute of Plant Genetics, Polish Academy of Sciences, Strzeszynska 34, 60-479, Poznan, Poland.
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Koczyk
mesh_terms: D001483:Base Sequence; D000460:Chlorophyta / Q000378:metabolism*; D059018:DNA Contamination; D048028:DNA, Algal / Q000302:isolation & purification*; D004271:DNA, Fungal / Q000302:isolation & purification*; D057230:Limit of Detection; D058086:Microalgae / Q000235:genetics; D024341:Xanthophylls / Q000096:biosynthesis
chemical_list: D048028:DNA, Algal; D004271:DNA, Fungal; D024341:Xanthophylls; C005948:astaxanthine
keywords: Contamination; Diagnostics; HRM; Haematococcus pluvialis; Microalgae