Algicidal Activity of Novel Marine Bacterium Paracoccus sp. Strain Y42 against a Harmful Algal-Bloom-Causing Dinoflagellate, Prorocentrum donghaiense

Abstract

blooms occur frequently in the Yangtze River estuary and the adjacent East China Sea. These blooms have damaged marine ecosystems and caused enormous economic losses over the past 2 decades. Thus, highly efficient, low-cost, ecofriendly approaches must be developed to control blooms. In this study, a bacterial strain (strain Y42) was identified as sp. and was used to lyse The supernatant of the strain Y42 culture was able to lyse, and the algicidal activity of this Y42 supernatant was stable with different temperatures and durations of light exposure and over a wide pH range. In addition to , Y42 showed high algicidal activity against, , and, suggesting that it targets primarily Pyrrophyta. To clarify the algicidal effects of Y42, we assessed algal lysis and determined the chlorophyll contents, photosynthetic activity, and malondialdehyde contents of after exposure to the Y42 supernatant. Scanning electron microscopy and transmission electron microscopy analyses showed that the Y42 supernatant disrupted membrane integrity and caused algal cell breakage at the megacytic zone. Photosynthetic pigment loss and significant declines in both photosynthetic efficiency and the electron transport rate indicated that the Y42 supernatant damaged the photosynthetic system of Malondialdehyde overproduction indicated that the Y42 supernatant caused lipid peroxidation and oxidative damage to membrane systems in the algal cell, ultimately leading to death. The findings of this study reveal the potential of Y42 to remove algal cells from blooms. is one of the most common dinoflagellate species that form harmful algal blooms, which frequently cause serious ecological pollution and pose health hazards to humans and other animals. Screening for bacteria with high algicidal activity against and studying their algicidal processes and characteristics will contribute to an understanding of their algicidal effects and provide a theoretical basis for preventing algal blooms and reducing their harm to the environment. This study reports the algicidal activity and characteristics of against The stability of the algicidal activity of in different environments (including different temperature, pH, and sunlight conditions) indicates its potential for use in the control of blooms.

Algicidal characterization and mechanism of Bacillus licheniformis Sp34 against Microcystis aeruginosa in Dianchi Lake

“…Ts‐12 against Phaeocystis globosa . MDA is produced by lipid peroxidation of the cell membrane, and its amount increases with the peroxidation of the membrane lipid . In this study, MDA content in algal cells was significantly increased, indicating that Sp34 supernatant caused oxidative damage to the algal cell membrane.…”

A method to assess algicidal activity of microalgal extracts coupling microalgae produced in stirred closed photobioreactor operating in continuous with pulse amplitude modulated (PAM) fluorometry

“…Pulse amplitude modulated (PAM) fluorometry [1] is a non-destructive method based on chlorophyll a fluorescence that was already successfully used in previous study to assess allelochemical interaction between microalgae [2] , [3] , [4] , algicidal / antialgal activity of marine bacterium [5] and herbicide activity of chemicals (e.g. Diuron [6] ).…”

“…It may therefore also be sensitive to cell energy metabolism and interactions between carbon and nitrogen assimilation. The use of microalgae produced in batch culture to carry out such experiment [2 , 5 , 6] may thus be controversial as these unbalanced culture conditions (e.g. pH, light, nutrient availability) continuously modify the microalgae photophysiology.…”

Biotechnological Potential of Bacteria Isolated from the Sea Cucumber Holothuria leucospilota and Stichopus vastus from Lampung, Indonesia

“…In addition, recent studies reported algicidal activities of Paracoccus sp. against harmful algal blooms of Prorocentrum donghaiense [42].…”