Effect and removal of bisphenol A by two extremophilic microalgal strains (Chlorophyta)

Abstract

The effects and the removal efficiency of bisphenol A (BPA) on two extremophilic Chlorophyta strains, an alkaliphilic Picocystis and a thermophilic Graesiella, were assessed. BPA was shown to inhibit the growth and photosynthesis of both species, but to a greater extent for Graesiella. The growth IC 50 (4 days) was 32 mg L −1 for Graesiella andhigherthan75mgL −1 for Picocystis. Oxidative stress was induced in both strains when exposed to increasing BPA concentrations, as evidenced by increased malondialdehyde content. BPA exposure also resulted in an over-expression of antioxidant activities (ascorbate peroxidase, glutathione S-transferase and catalase) in Picocystis whereas they were repressed in Graesiella. Both species exhibited high BPA removal efficiency, reaching 72% for Picocystis and 52.6% for Graesiella at 25 mg L −1 . BPA removal was mostly attributed to biodegradation for both species. Overall, according to its extended tolerance and its removal capacity, Picocystis appeared to be a promising species for the BPA bioremediation even at high contamination levels.

Can BPA Analogs Affect Cellular and Biochemical Responses in the Microalga Phaeodactylum tricornutum Bohlin?

“…In addition, increased activity of both CAT and GST was reported in Picocystis sp. exposed to 25, 50, and 75 mg/L of BPA [ 53 ]. As for GR, which is an enzyme involved in the glutathione cycle, we did not observe any effects of the tested compounds during exposure.…”

“…when it was treated for 1, 2, 3, 4, and 5 days with 25, 50, and 75 mg/L; in addition, after 4 and 5 days, the APX activity was also increased by 10 mg/L of BPA. However, at 1 mg/L of BPA, no alterations in APX activity were recorded [ 53 ]. In the latter study, the activity of APX measured in Graesiella sp.…”

“…In the latter study, the activity of APX measured in Graesiella sp. showed an opposite pattern of variation with respect to that of Picocystis sp., with decreased enzyme activity at higher BPA concentrations [ 53 ].…”

Bio-removal of bisphenol A by cyanobacterium Gloeocapsopsis crepidium

“…Both species showed high BPA removal efficiencies, with Graesiella reaching 52.6% and Picocystis reaching 72% at 25 mg/L. The removal of BPA was mainly attributed to biodegradation by both species (Ben Ouada et al, 2018). Another study showed that a monoculture of Chlorella sorokiniana was able to partially remove BPA (Eio et al, 2015).…”