Immobilization of algicidal bacterium Shewanella sp. IRI-160 and its application to control harmful dinoflagellates.

Abstract:

:Shewanella sp. IRI-160 is an algicidal bacterium isolated from Delaware Inland Bays. It secretes water-soluble compounds that inhibit the growth of dinoflagellates. Previous research indicated that this bacterium does not have a negative impact on other algal species. In this research, Shewanella sp. IRI-160 was immobilized to different porous matrices, including agarose, alginate hydrogel, cellulosic sponge, and polyester foam. The retention of Shewanella sp. IRI-160 on or within these matrices was examined at 4 and 25 °C for 12 days. Results indicated that alginate was superior in terms of cell retention, with >99% of Shewanella cells retained in the matrix after 12 days. Shewanella sp. IRI-160 cells were then immobilized within alginate beads to evaluate algicidal effects on harmful dinoflagellates Karlodinium veneficum and Prorocentrum minimum at bacterial concentrations of 106 to 108 cells mL-1. The effects on dinoflagellates were compared to non-harmful cryptophyte Rhodomonas sp., as well as the effects of free-living bacteria on these species. Results indicated that immobilized Shewanella sp. IRI-160 in alginate beads were as effective as the free-living bacteria to control the growth of K. veneficum and P. minimum, while no negative impacts of immobilized Shewanella sp. IRI-160 on the non-harmful control species Rhodomonas sp. were observed. Overall, this study suggests that immobilized Shewanella sp. IRI-160 may be used as an environmentally friendly approach to prevent or mitigate the blooms of harmful dinoflagellates and provides insight and directions for future studies.

journal_name

Harmful Algae

journal_title

Harmful algae

authors

Wang Y,Coyne KJ

doi

10.1016/j.hal.2020.101798

subject

Has Abstract

pub_date

2020-04-01 00:00:00

pages

101798

eissn

1568-9883

issn

1878-1470

pii

S1568-9883(20)30078-0

journal_volume

94

pub_type

杂志文章