Identification of toxic fatty acid amides isolated from the harmful alga Prymnesium parvum carter

Low pH preempts bloom development of a toxic haptophyte

“…In an effort to interpret such observations, Valenti et al (2010a) hypothesized that toxins produced by P. parvum behave like weak bases, which become more nonionized, bioavailable, and toxic with increasing pH. Observations in the present study are also consistent with more recent, groundbreaking findings from Bertin et al (2012a,b) who provided a novel report of a new class of toxins, fatty acid amides, produced by P. parvum (Bertin et al, 2012a), and demonstrated that increasing pH increased toxicity of two of these fatty acid amides, oleamide and linoleamide, to rainbow trout gill cells (Bertin et al, 2012b). Clearly, additional toxicological research is warranted on impacts of fatty acid amides associated with P. parvum blooms in inland waters.…”

The contribution of fatty acid amides to Prymnesium parvum Carter toxicity

“…Many molecules have been implicated in the toxicity of P. parvum (Igarashi, 1999;Manning and La Claire, 2010), and we recently have shown that toxic fatty acid amides are previously undescribed toxic compounds of this species (Bertin et al, 2012). Neurotoxic, cytotoxic, ichthyotoxic, and hemolytic effects have all been attributed to P. parvum toxins (Yariv and Hestrin, 1961).…”

Semi-quantitative assay for polyketide prymnesins isolated from Prymnesium parvum (Haptophyta) cultures

“…There are many seemingly contradictory reports concerning the levels and types of toxicity that polyketide prymnesins (PPs) exhibit, partly because their ichthyotoxic properties reportedly require co-factors, such as divalent cations, antibiotics or polyamines (Manning and La Claire, 2010a). Also, additional toxic principles have been reported more recently from this alga, including galactolipids, polyunsaturated fatty acids (PUFAs) and fatty acid amides (FAAs) (Henrikson et al, 2010;Bertin et al, 2012aBertin et al, , 2012b; however, the ichthyotoxicity of some of these compounds has been questioned recently (Blossom et al, 2014b). Because a variety of extraction protocols and bioassays have been employed over the past few decades in attempt to (semi-)quantify the "toxicity" of P. parvum, it is nearly impossible to determine precisely which compounds are responsible for the various forms of toxicity that have been observed (Brooks et al, 2010;Manning and La Claire, 2010a).…”