Response of algae and zooplankton to C18 fatty acids of Chlamydomonas reinhardtii

Abstract

Three C 18 fatty acids were assayed for their activity against a number of algae and zooplankton . The three acids, lenolenic, lenoleic, and oleic, reduced the growth of Haematococcus lacustris, Synechococcus leopoliensis, and Botrydiopsis alpina by 50% of control growth in concentrations below 7 ppm . Calanoid and cyclopoid copepods in mixed cultures inoculated with lenolenic and lenoleic acid had LD 50 values below 10 ppm. An increase in copepod mortality was observed with increases in cyclopoid density and decreased with increases in calanoid density . Eucyclops agilis inoculated with lenolenic acid had a LD 50 value of 4 ppm .

Growth inhibition of Monodus subterraneus by free fatty acids

“…Up till now, mainly unsaturated or polyunsaturated fatty acids of C 18 or C 20 or their oxygenated products are mentioned as the main growth inhibiting compounds for microalgae (Ikawa et al, 1984(Ikawa et al, , 1997McCracken et al, 1980;Spruell, 1984;Yamada et al, 1993). However, our results show that the inhibition can also be caused by saturated fatty acids.…”

“…Fatty acids and their oxidation products are often considered as algal growth inhibitors (Ikawa et al, 1984(Ikawa et al, , 1997McCracken et al, 1980;Spruell, 1984;Wu et al, 2006;Yamada et al, 1993). Fatty acids are known to be important physiological and ecological markers that can be excreted in the culture medium (Sushchik et al, 2001(Sushchik et al, , 2003.…”

ALLELOCHEMICALS OF BOTRYOCOCCUS BRAUNII (CHLOROPHYCEAE)1

“…Linolenic acid from Chlorococcum and Dunaliella might act as an antibiotic against microorganisms (Ohta et al 1995). C 18 fatty acids were proven to be toxic to zooplankton (Spruell 1984). Thus, it is possible that, like many phytoplankton, B. braunii uses free fatty acids as an allelochemical to inhibit the growth of other plankton in its natural environment.…”

Potencial contaminante del mar por aguas residuales de las industrias de harinas y aceites de pescado

“…El valor de pH compatible con la vida de los peces está comprendido entre 5 y 9, pero para la mayoría de las especies acuáticas la zona de pH favorable se sitúa entre 6 y 7,2. Entre otros factores existe evidencia de que el medio ácido aumenta la toxicidad de los ácidos grasos oleico y linoleico sobre los peces (Spruell, 1984). El efecto tóxico de la disminución del pH de los vertidos analizados dependerá obviamente de la dilución del vertido en dependencia de las cantidades totales de agua residual y el grado de recambio del medio marino.…”