Influence of herbicides on the growth and composition of the yellow-green alga Trachydiscus minutus

The yellow-green alga Trachydiscus minutus has not been studied in detail prior to the first decade of the 21 st century due to the fact it has been easily confused with the algae of the genus Chlorella. It is known that the cells of the algae have a high amount of lipids and proteins and they lack chlorophyll-b. Currently, there is no published data available to describe the effects of herbicides on growth and biochemical composition. The aim of this work is to study the effects of the glyphosate-containing herbicide Roundup and the effects of atrazine on the growth of Trachydiscus minutus, its pigment and protein composition, its lipid composition and fatty acid profile. Both herbicides are able to significantly inhibit the growth of the algal cultures if they are treated with concentrations higher than 20 mg/l. The protector spermine was unsuccessfully used to overcome the inhibitory effects of atrazine on Trachydiscus minutus. Both glyphosate and atrazine are shown to lower the content of pigments in the algal cells. The influence of both atrazine and glyphosate on the content of eicosapentaenoic acid is insignificant, while spermine enhances its percentage.