Ecotoxicity of the lipid-lowering drug bezafibrate on the bioenergetics and lipid metabolism of the diatom Phaeodactylum tricornutum

Fluoxetine Arrests Growth of the Model Diatom Phaeodactylum tricornutum by Increasing Oxidative Stress and Altering Energetic and Lipid Metabolism

“…Following direct trans-esterification of cell pellets, in freshly prepared methanol sulfuric acid (97.5:2.5, v/v), at 70°C for 60 min, fatty acids methyl esters (FAMEs) were recovered using petroleum ether and dried under a N 2 flow in a dry bath at 30°C ( Feijão et al, 2018 ; Duarte et al, 2019 ). Hexane resuspended FAMEs were analyzed in a gas chromatograph (Varian 430-GC gas chromatograph) equipped with a hydrogen flame ionization detector set at 300°C.…”

Glyphosate-Based Herbicide Toxicophenomics in Marine Diatoms: Impacts on Primary Production and Physiological Fitness

“…According to the Organization for Economic Cooperation and Development (OECD) guidelines for algae bioassays [53] and the recommended initial cell density for microalgae cells with similar size to P. tricornutum, initial cell concentration was approximately 2.7 × 10 5 cells mL −1 . Forty-eight hours after inoculation, cultures were exposed to 0, 10, 50, 100, 250, or 500 µg L −1 glyphosate for 48 h [24,41,46], obtained from the glyphosate-based herbicide "Roundup ® Pronto" containing 7.2 g L −1 of glyphosate. Since no studies have measured glyphosate in marine water, the herbicide concentrations were chosen based on the range of environmental concentrations found in agricultural water streams in relevant literature [49][50][51][52], as it was found that this chemical presents the same half-life in saltwater as it does in freshwater [10,11].…”

“…While other substances compose Roundup ® , glyphosate is the main active component. Exposure took place 48 h after inoculation to ensure that the experiment was performed during the cell exponential growth phase [24,41,46]. There were three replicates for each herbicide concentration from a total of 18 experimental units.…”

“…Culture cell density was assessed daily, using a non-actinic light to measure minimum chlorophyll fluorescence (F 0 ). Analysis of chlorophyll transient light curves (Kautsky plot) was carried out using the OJIP test according to [41]. Fluorometric analysis parameters and their description can be accessed in Table 1.…”

“…In both cases, there was inhibition of CO 2 assimilation and depletion of intermediates from the photosynthetic carbon reduction cycle due to deregulation of the shikimate pathway [39,40]. In such scenarios, non-invasive high-throughput bio-optical screening tools, such as Pulse Amplitude Modulated (PAM) fluorometry, emerge as invaluable techniques to evaluate ecotoxicity in photosynthetic organisms [12,41,42]. Through PAM it is possible to translate the fluorescence signals as proxies to the bioenergetics involved in photosynthesis in a non-destructive form [13,[41][42][43][44] to efficiently assess primary productivity [45,46] and the physiological effects in plant material at different concentrations of contaminants [12,41,42,44].…”