Novel Derivatives of 9,10-Anthraquinone Are Selective Algicides against the Musty-Odor CyanobacteriumOscillatoria perornata

Abstract

Musty "off-flavor" in pond-cultured channel catfish (Ictalurus punctatus) costs the catfish production industry in the United States at least $30 million annually. The cyanobacterium Oscillatoria perornata (Skuja) is credited with being the major cause of musty off-flavor in farm-raised catfish in Mississippi. The herbicides diuron and copper sulfate, currently used by catfish producers as algicides to help mitigate musty off-flavor problems, have several drawbacks, including broad-spectrum toxicity towards the entire phytoplankton community that can lead to water quality deterioration and subsequent fish death. By use of microtiter plate bioassays, a novel group of compounds derived from the natural compound 9,10-anthraquinone have been found to be much more selectively toxic towards O. perornata than diuron and copper sulfate. In efficacy studies using limnocorrals placed in catfish production ponds, application rates of 0.3 M (125 g/liter) of the most promising anthraquinone derivative, 2-[methylamino-N-(1-methylethyl)]-9,10-anthraquinone monophosphate (anthraquinone-59), dramatically reduced the abundance of O. perornata and levels of 2-methylisoborneol, the musty compound produced by O. perornata. The abundance of green algae and diatoms increased dramatically 2 days after application of a 0.3 M concentration of anthraquinone-59 to pond water within the limnocorrals. The half-life of anthraquinone-59 in pond water was determined to be 19 h, making it much less persistent than diuron. Anthraquinone-59 appears to be promising for use as a selective algicide in catfish aquaculture.

Existing and emerging cyanocidal compounds: new perspectives for cyanobacterial bloom mitigation

“…To provide better solubility, 9,10-anthraquinone was modified to anthraquinone-59 (2-[methylamino-N-(1-methylethyl)]-9,10-anthraquinone). By use of micro-titre plate bioassays, this novel compound was found to be much more selectively toxic towards O. perornata than diuron and copper sulphate, and in studies using limno corrals placed in catfish production ponds for gradual release, application rates of 0.3 lM (125 lg L -1 ) of the anthraquinone-59 drastically reduced the abundance of O. perornata and levels of 2-methylisoborneol, the musty compound produced by O. perornata (Schrader et al 2003). More water-soluble anthraquinone analogues with interesting ecotoxicological properties have been synthesized recently (Nanayakkara and Schrader 2008).…”

“…It also causes thylakoid disorganization (identical to the reported modification in a cyanobacterium treated with simazine) and reduces the number of ribosomes (Schrader et al 2000). Unfortunately, this compound did not effectively reduce the abundance of cyanobacteria in catfish production ponds, possibly due to its early precipitation (Schrader et al 2003). To provide better solubility, 9,10-anthraquinone was modified to anthraquinone-59 (2-[methylamino-N-(1-methylethyl)]-9,10-anthraquinone).…”

Contribution of Streptomyces in sediment to earthy odor in the overlying water in Xionghe Reservoir, China

“…These compounds are semi-volatile terpenoids produced as secondary metabolites by planktonic and benthic cyanobacteria, actinomycetes, fungi, and myxobacteria (Schulz et al, 2004;Wood et al, 1983). In an effort to eliminate these types of taste and odor compounds, many studies have been aimed at preventing the growth of cyanobacteria based upon the isolation and identification of odor-producing cyanobacteria and the conditions promoting their growth in natural lakes and ponds (Schrader et al, 2003;Murray-Gulde et al, 2002). However, the application of these preventive measures may not be appropriate in odorous waters where the organisms responsible for geosmin and 2-MIB production are not cyanobacteria.…”

A marine algicidal actinomycete and its active substance against the harmful algal bloom species Phaeocystis globosa

“…losses (Blauw et al 2010), with the economic loss from HAB-related events in the United States having been estimated to be worth several billions of U.S. dollars annually (Schrader et al 2003).…”