Network Component Analysis Can Identify Potential Axenisation Strategies Circumventing Antibiotic‐Use for Phototrophic Eukaryotic Microalgae

Environmental Microbiology Reports, vol. 18, pp. e70290

Abstract

Axenisation of phototrophic eukaryotic microalgae has been studied for over a century, with antibiotics commonly employed to achieve axenic cultures. However, this approach often yields inconsistent outcomes and contributes to the emergence of antibiotic-resistant microbes. A comprehensive analysis of previous reports on axenisation was necessary to identify alternate workflows tailored to each major microalgal group. Literature from scholarly databases was systematically recovered and network component analysis was performed to identify method-clusters commonly reported for the axenisation of diatoms, dinoflagellates, and green algae. Promising workflows circumventing the use of antibiotics appeared to be filtration ↔ washing ↔ micropicking for diatoms, and micropicking ↔ subculturing ↔ flow cytometry for dinoflagellates. No clear workflow could emerge for green algae although Streak plating ↔ Flowcytometry → Ultrasonication was considered despite these methods appearing in different clusters. Furthermore, the literature suggests that a combination of microscopy (e.g., epifluorescence), cell counting (e.g., agar plating), and sequencing (16S and/or 18S) was essential to confirm the final purity of the mother culture. More systematic and high-quality primary research is required to identify effective workflows for other microalgal divisions and fortify/contrast the ones proposed herein based on network component analysis.

Authors 5

1. Ajay Balu Iyer

   University College Dublin

   Affiliation as printed

   Conway Institute of Biomolecular Research University College Dublin Belfield Ireland

   UCD Algae Group, School of Biosystems and Food Engineering University College Dublin Dublin Ireland

2. Matthias Monissen Aachen

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University Aachen Germany

3. Q. Teo

   University College Dublin

   Affiliation as printed

   Conway Institute of Biomolecular Research University College Dublin Belfield Ireland

   UCD Algae Group, School of Biosystems and Food Engineering University College Dublin Dublin Ireland

4. Oskar Modin

   Chalmers University of Technology

   Affiliation as printed

   Architecture and Civil Engineering Chalmers University of Technology Gothenburg Sweden

5. Ronald Halim corresponding

   University College Dublin

   Affiliation as printed

   Conway Institute of Biomolecular Research University College Dublin Belfield Ireland

   UCD Algae Group, School of Biosystems and Food Engineering University College Dublin Dublin Ireland