Chiral Analysis of Pesticides and Drugs of Environmental Concern: Biodegradation and Enantiomeric Fraction

The importance of stereochemistry for medicinal chemistry and pharmacology is well recognized and the dissimilar behavior of enantiomers is fully documented. Regarding the environment, the significance is equivalent since enantiomers of chiral organic pollutants can also differ in biodegradation processes and fate, as well as in ecotoxicity. This review comprises designed biodegradation studies of several chiral drugs and pesticides followed by enantioselective analytical methodologies to accurately measure the enantiomeric fraction (EF). The enantioselective monitoring of microcosms and laboratory-scale experiments with different environmental matrices is herein reported. Thus, this review focuses on the importance of evaluating the EF variation during biodegradation studies of chiral pharmaceuticals, drugs of abuse, and agrochemicals and has implications for the understanding of the environmental fate of chiral pollutants.The authors wish to thank Fundação para a Ciência e Tecnologia—FCT for financial support under the project Fluoropharma PTDC/EBB-EBI/111699/2009, the PhD grant attributed to Alexandra S. Maia SFRH/BD/86939/2012, QREN-POPH, European Social Fund, MCTES, PEst FCOMP-01-0124-FEDER-022718; PEst-OE/EQB/LA0016/2011, PEst-OE/SAU/UI4040/2014. This research was partially supported by the Strategic Funding UID/Multi/04423/2013 through national funds provided by FCT—Fundação para a Ciência e Tecnologia and European Regional Development Fund (ERDF), in the framework of the program PT2020 and by CESPU (ChiralDrugs_CESPU_2017

Biodegradation of chiral pharmaceuticals by an activated sludge consortium followed by a Chiral HPLC-FD

Biodegradation tends to be enantioselective in contrast to abiotic degradation and it is necessary enantioselective analytical methods to quantify the enantiomeric fraction of chiral pharmaceuticals in the environment for correct risk assessment. In this work, we developed HPLC-FD methods to follow the biodegradation of four beta-blockers: alprenolol , propranolol , metoprolol and atenolol and the antidepressant fluoxetine during 15 days in batch mode. The biodegradation assays were performed using AS from the aerated tanks of a municipal wastewater treatment plant with a singly compound supplementation and a mixture compound supplementation similar to those found in wastewater influents. Abiotic degradation in the presence of light and in the dark was evaluated. Either the low concentration or the mixture effects are situations closer to those found in the environment. The results indicate the higher degradation extents for the S-enantiomer forms, as is shown in Figure 1

Residual Effect of the Phosphate Fertilization and Filter Cake on the Sugarcane Ratoon Breaking.

RESUMO: O fósforo é considerado um elemento essencial para as plantas e se encontra em baixa quantidade nos solos brasileiros. Na cana-de-açúcar, assume grande importância no enraizamento e no perfilhamento e, portanto, na produtividade final. São restritas as informações sobre o efeito residual da adubação fosfatada para a cana soca. Este trabalho teve por objetivo avaliar a rebrota da cana-de-açúcar em função da adubação com torta de filtro enriquecida com fontes solúveis de fósforo, realizada no plantio. O experimento foi realizado a campo em Presidente Prudente-SP com a variedade RB867515. Utilizou-se o delineamento experimental em blocos completos ao acaso, no esquema fatorial 5 x 4, sendo o primeiro fator os níveis de torta de filtro (0; 0,5; 1,0; 2,0 e 4,0 ton.ha-1) e o segundo os níveis de fósforo (0, 50, 100, 200 kg.ha-1 de P2O5), com 4 repetições. O número de perfilhos por metro linear foi avaliado aos 60 dias após a rebrota. As doses de fósforo associada à torta de filtro, aplicadas no plantio da cana-de-açúcar, favorecem a brotação da primeira soqueira. Doses de 4,0 ton.ha-1 de torta de filtro, aplicadas com o fósforo mineral, elevam a brotação das soqueiras, assim como as doses de P2O5, a partir de 50 Kg.ha-1. ABSTRACT: Residual Effect of the Phosphate fertilization and filter cake on the sugarcane ratoon breaking. The phosphorus is considered an essential element for the plants and is in low amount in the Brazilian soils. In the sugarcane, assumes great importance in the rooting and tiller, increasing the productivity. They are restricted the information on the residual effect of the phosphorus manuring for the sugarcane it beats. This work had for objective to evaluate the coppicing of the sugarcane in function of the manuring with filter cake enriched with soluble phosphate. The experiment, carried through in Presidente Prudente-SP, used a randomized complete block design, in the factorial outline 5 x 4, where the first factor consisted of doses of filter cake (0; 0,5; 1,0; 2,0 and 4,0 ton ha-1) and the second, doses of phosphorus fertilizer (0, 50, 100, 200 Kg ha-1 of P2O5), with 4 repetitions. The tiller number for lineal meter was evaluated to the 60 days after the coppicing. The phosphorus doses associated to the filter cake, applied in the planting of the sugarcane, they favor the coppice of the first ratoon. Doses of 4,0 ton ha-1 of filter cake, applied with the phosphorus mineral, they elevate the ratoons coppice, as well as the doses of P2O5, starting from 50 Kg ha-1.bitstream/item/72728/1/Foloni-RevistaAgrarian-v5-2012.pd

Solid Phase Extraction of Fluoroquinolone Antibiotics from Wastewaters – Assessment of Different Commercial Sorbents

Microbial degradation of fluorinated pharmaceuticals during wastewater treatment processes remains inadequate in most situations. Due to incomplete elimination, these residues are continually being introduced into the aquatic environments in which they settle throughout time since many of them are resistant to degradation. Fluoroquinolone antibiotics due to its persistence and implication on resistant-bacteria development, pose special interest in environmental analysis. Due to their zwitterionic characteristics, the extraction/pre-concentration process of fluoroquinolones prior analyses is an unquestionable challenge. This work compares the solid phase extraction efficiency of four fluoroquinolones (Ofloxacin, Norfloxacin, Ciprofloxacin and Moxifloxacin) from wastewater effluents by different commercial sorbents. Prior to wastewater analysis, preliminary tests were conducted in distilled water with a larger number of sorbents. Different experimental protocols and sorbents, namely OASIS® HLB, OASIS® WAX, OASIS® WCX (500 mg) and the molecularly imprinted polymer SupelMIP TM were applied to wastewater samples collected from a municipal wastewater treatment plant from the north of Portugal. The extracts were analyzed by a HPLC withFluorescence Detection validated method using a Luna PFP (2) 3µm column. Despite good results obtained with the molecularly imprinted polymer in distilled water, these cartridges did not perform efficiently when applied to wastewater effluents, probably due to the sample high complexity especially since their specific design for biological samples. Regarding OASIS® considered sorbents; HLB 500mg and WAX 500mg presented the best recovery rates of the fourstudied antibiotics, between 84-75% and 64-94%, respectively. Although the recoveries achievedwere not that dissimilar between the two mentioned sorbents, chromatograms of WAX extracts appear much cleaner in the antibiotics retention times while chromatograms of HLB extractsclearly show the presence of strong polar substances, probably matrix humic and fulvic acids,that behave as resilient interferences in the analysis, disturbing a proper identification of target compounds and reducing chromatographic resolution

Biodegradation of Beta-Blockers and Fluoxetine followed by a Chiral HPLC-FD

Despite of the massive publications concerning pharmaceuticals in the environment, the problematic related with chiral compounds and enantioselective degradation are still largely unknown [1]. Enantiomers have different interactions with enzymes, receptors and other chiral molecules, leading to different biological activities. Thus, biodegradation tends to be enantioselective in contrast to abiotic degradation. However, biodegradation studies regarding enantioselectivity on the process are scarce [2].] MATERIALS AND METHODS [Four beta-blockers: alprenolol (ALP), propranolol (PHO), metoprolol (MET) and atenolol (ATE) and the antidepressant fluoxetine (FX) were enantiomerically separated by a macrocyclic antibiotic vancomycin CSP (ASTEC Chirobiotic V 5µm) under polar organic mode phase (methanol:ethanol:triethylamine:acetic acid.50:50 v/v) and fluorescence detection for enantiomeric fraction quantification. The developed methods were established using a minimal medium inoculated with activated sludge (AS) as a matrix.] RESULTS AND DISCUSSION [The Chirobiotic VTM was able to resolve ALP and PHO as well as MET, ATE and FX in two short runs. A separation factor (α) between 1.12 and 1.34 and resolution (Rs) between 1.30 and 4.35 were obtained. The methods demonstrated to be selective and linear within the range, with detection limits between 2.5 and 10ng/mL. These methods were applied to follow the biodegradation of the target compounds. The biodegradation assays were performed using AS from a municipal WWTP and the results indicate the higher degradation extents for the S- enantiomer forms at initial concentrations tenfold above those found in the environment (10ppm and 5ppm). The same assays were performed at an initial concentration of 1ppm for a singly supplementation and at 0,5ppm for a mixture of compounds, a closer situation to the real environment.] CONCLUSIONS [To our knowledge, chromatographic enantioseparations of the mixture of ALP and PHO and the mixture of MET, FX and ATE using the Chirobiotic™ V, have not been previously reported. The feasibility of this application was confirmed by two biodegradation studies using AS, with S-form being faster degraded, showing stereoselectivity

Chiral analysis of pesticides and drugs of environmental concern: biodegradation and enantiomeric fraction

The importance of stereochemistry for medicinal chemistry and pharmacology is well recognized and the dissimilar behavior of enantiomers is fully documented. Regarding the environment, the significance is equivalent since enantiomers of chiral organic pollutants can also differ in biodegradation processes and fate, as well as in ecotoxicity. This review comprises designed biodegradation studies of several chiral drugs and pesticides followed by enantioselective analytical methodologies to accurately measure the enantiomeric fraction (EF). The enantioselective monitoring of microcosms and laboratory-scale experiments with different environmental matrices is herein reported. Thus, this review focuses on the importance of evaluating the EF variation during biodegradation studies of chiral pharmaceuticals, drugs of abuse, and agrochemicals and has implications for the understanding of the environmental fate of chiral pollutants.info:eu-repo/semantics/publishedVersio