Removal of Aqueous 17α-Ethinylestradiol by <i>Rhodococcus</i> Species
Bibliographic record
Abstract
Pharmaceutical substances such as 17α-ethinylestradiol (EE2), the active component of the contraceptive pill, are often not eliminated during wastewater treatment and are persistent in the environment. Using solid-phase extraction and chromatography methods for analyzing low concentrations of EE2 and metabolites, biodegradability of EE2 was studied using four bacteria grown under aerobic conditions in the absence or presence of a readily available carbon source (2.5 g/L of adipic acid or glucose). Preliminary identification of produced metabolites was also completed. In presence of a cosubstrate, Rhodococcus erythropolis removed EE2 up to 47% of its initial concentration (1.4 and 0.5 mg/L) in 13 h, while it removed only 10% after 75 h without a cosubstrate. In the presence of a cosubstrate, Rhodococcus equi removed EE2 up to 39% of its initial concentration (1.4 mg/L) after 65 h, whereas no significant EE2 removal was observed using Rhodococcus rhodochrous and Rhodococcus zopfii. Preliminary analysis of EE2 transformation products confirmed the presence of phenol and a compound of high molecular weight (331 amu). These results improve our understanding of the effect of common biological wastewater treatment variables such as bacteria strains, acclimation, and presence of cosubstrate, on the removal of EE2.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".