Decontamination protocol of the macroalga Bostrychia binderi Harvey (Rhodophyta) for unialgal cultures and laboratory studies

Abstract

This study aimed to test the effectiveness of physical and chemical procedures for surface decontamination of Bostrychia binderi Harvey. For this, thalli were washed and immersed in chemical solutions (5% liquid detergent, 1% povidone iodine and 0.2% sodium hypochlorite) at different times and combinations. After treatments the thalli were cultivated in laboratory to verify possible negative effects caused by the procedures to alga. Contaminating organisms in the algal culture medium were quantified at the end of cultivation. Washing, spraying, removal of macrofauna individuals with tweezers, thalli immersion in 5% liquid detergent for 60 seconds, after in 0.2% sodium hypochlorite for 2 minutes were effective procedures to eliminate all contaminants analyzed. Thalli immersion in 1% povidone iodine did not affect negatively the thalli growth, whereas immersion in 0.2% sodium hypochlorite for 5 minutes affected. For establishment of Bostrychia unialgal cultures we recommend the protocol proposed in this study.

Image-Based Analysis and Quantification of Biofouling in Cultures of the Red Alga Asparagopsis taxiformis

“…Epiphytes may compete with target algae for resources or may physically settle on and grow over their surfaces, compromising light capture and water movement, subsequently leading to diminished growth and the dilution of target species. Some epiphytes may also be pathogenic (Borburema et al 2021;Behera et al 2022).…”

Image-based analysis and quantification of biofouling in cultures of the red alga Asparagopsis taxiformis

“…Contamination of algae cultures may be caused by many organisms, including competing algae (e.g. Diatoms: Shea et al 2006, Winckelmann et al 2016cyanobacteria: Meseck 2007;andgreen algae: Grivalský et al 2021, Behera et al 2022), epiphytes (Borburema et al 2021;Behera et al 2022), fungi and bacteria (Fott 1967;Berland et al 1972;Gutman et al 2009;Carney and Lane 2014;Fulbright et al 2018), and zooplankton grazers (mainly ciliates, rotifers, copepods, amoeba, and dinoflagellates: Deore et al 2020;Di Caprio 2020). Biological contamination of both micro and macroalgal cultures is one of the greatest challenges for efficient, reliable and scalable production of algal biomass (Fernandes et al 2011;Deore et al 2020;Zhu et al 2020;Behera et al 2022).…”