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Occurrence and removal of drugs of abuse in Wastewater Treatment Plants of Valencia (Spain)
2014
Andrés-Costa, María Jesús | Rubio-López, Nuria | Morales Suárez-Varela, María | Picó, Yolanda
The occurrence of 8 drugs of abuse and metabolites in the influent and effluent of the 3 Wastewater Treatment Plants (WWTP) that treat wastewater from Valencia was studied in 2011, 2012 and 2013. Target drugs except 6-monoacetylmorphine (6-ACMOR) were detected in 100% of the influents. The WWTPs eliminate cocaine (COC), amphetamine (AMP), methamphetamine (MAMP) and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH). Benzoylecgonine (BECG) was also efficiently eliminated (93–98%), whereas 3,4-methylenedioxymethamphetamine (MDMA) presented removal rates of 32–57% and ketamine (KET) was not eliminated. The most consumed illicit drugs, according to the estimated concentrations of each compound in the studied WWTPs, were cannabis and COC followed by KET, AMP, MAMP, MDMA and heroin. Environmental risk assessment was evaluated by calculating Risk Quotient (RQ). MDMA and KET could pose a medium risk and low risk, respectively, to the aquatic organisms. Although short-term environmental risk is not worrisome, long-term effects cannot be known exactly.
Afficher plus [+] Moins [-]Molecular, functional, and cellular alterations of oocytes and cumulus cells induced by heat stress and shock in animals
2020
Abdelnour, Sameh A. | Yang, Chun-Yan | Swelum, Ayman A. | Abd El-Hack, Mohamed E. | Khafaga, Asmaa F. | Abdo, Mohamed | Shang, Jiang-Hua | Lu, Yang-Qing
Global warming is considered as the main environmental stress affecting ecosystems as well as physiological and biochemical characteristics, and survivability of living organisms. High temperature induces various stresses and causes reduction of fertility through reducing the oocyte developmental competence and alteration in surrounding cells’ functions. This causes major economic loss to livestock creating a selective pressure on animals to the advantage of better adapted genotypes and to the detriment of others. In this review, a search in Science Direct, Google Scholar, PubMed, Web of Science, Scopus, and SID databases until 2020 was conducted. Keywords which include heat stress, shock, high temperature, oocyte, cumulus, and animals were investigated. Studies have exhibited that heat stress can disturb the development and function of oocyte and cumulus cells (CCs) concerning reproductive efficiency. Heat stress has deleterious consequences on oocyte maturation and development via reduced number of polar body extrusion, adenosine monophosphate, and guanosine monophosphate synthesis. Heat stress caused the alteration of cytoplasmic and nuclear features as well as trans-zonal projections and gap junctions. In addition, heat stress is accompanied with reduced mitochondrial activity (copy mDNA number, distribution, and membrane potential) in cumulus–oocyte complexes. This review targets the description of results in the most recent studies that aimed to call attention to the influences of heat stress on molecular, functional, and cellular changes in oocytes and CCs in animals to design evidence on the acting mechanisms as the core of this problem from a comparative review.
Afficher plus [+] Moins [-]Ascorbic acid regulates nitrogen, energy, and gas exchange metabolisms of alfalfa in response to high-nitrate stress
2022
Niu, Junpeng | Chen, Zhao | Yu, Su | Wang, Quanzhen
The effects of exogenous ascorbic acid (AsA) on the growth parameters, nitrogen metabolism, energy status, and photosynthetic gas exchange in alfalfa under high-nitrate stress were studied. The seedlings treated with the control, 200 mmol L⁻¹ nitrates (HN) or 200 mmol L⁻¹ nitrate + 0.1 mmol L⁻¹ AsA (HN + AsA), were sampled on days 0 and 10 after treatments. AsA was sprayed on the leaves, while HN was conducted by watering. Both of them were performed once every other day for three times in total. The results revealed that in the HN treatment, the growth parameters were the lowest; total phosphorus (TP), nitrogen-related enzyme activities, soluble protein (SP), adenosine triphosphate (ATP), and energy charge (EC) were reduced; and photosynthetic rate (Photo), conductance to H₂O (Cond), transpiration rate (Trmmol), instantaneous water use efficiency (WUE), and apparent CO₂ use efficiency (CUE) were also inhibited; and total nitrogen (TN), nitrate-nitrogen (NO₃¯-N), ammonium-nitrogen (NH₄⁺-N), adenosine diphosphate (ADP), adenosine monophosphate (AMP), and intercellular CO₂ concentration (Ci) were increased compared with the control. However, these parameters changed conversely in the HN + AsA treatment. In addition, there was a good curve regression equation relationship between TN and NO₃¯-N, TN and NH₄⁺-N, NO₃¯-N and NH₄⁺-N, respectively. It indicates that AsA improves the growth parameters, nitrogen-related enzyme activities, energy metabolism, and photosynthesis, whereas it inhibits the toxicity of excess NO₃¯-N and NH₄⁺-N accumulations, thereby promoting the growth of alfalfa under high-nitrate stress. These metabolisms are closely related to each other during the regulatory process in alfalfa. Hence, AsA has potential to be applied to improve the growth of alfalfa under high-nitrate stress.
Afficher plus [+] Moins [-]Cu(II)-catalyzed degradation of ampicillin: effect of pH and dissolved oxygen
2018
Guo, Yiming | Tsang, Daniel C. W. | Zhang, Xinran | Yang, Xin
Cu(II)-catalyzed hydrolysis of β-lactam antibiotics has been well-identified and recognized as the key mechanism of antibiotic degradation. However, the overlooked Cu(II) oxidation susceptibly also plays an important role comparably with hydrolysis. This study evaluated the roles of hydrolysis and oxidation in Cu(II)-catalyzed degraded ampicillin (AMP), as a typical β-lactam antibiotic, under relevant environmental conditions (pH 5.0, 7.0, and 9.0; oxygen 0.2 and 6.2 mg/L). Under AMP and Cu(II) molar ratio of 1:1, AMP degradation was the fastest at pH 9.0, followed by pH 5.0 and pH 7.0. The facilitation of oxygen on AMP degradation was notable at pH 5.0 and 7.0 rather than pH 9.0. AMP degradation rate increased from 21.8% in 0.2 mg/L O₂ solution to 85.9% in 6.2 mg/L O₂ solution at pH 7.0 after 4-h reaction. AMP oxidation was attributed to both oxygen-derived Cu(I)/Cu(II) cycle and intermediate reactive oxygen species (HO. and O₂.⁻). Several intermediate and final products in AMP degradation were firstly identified by LC-quadrupole time-of-flight-MS analysis. Phenylglycine primary amine on the AMP structure was the essential complexation site to proceed with the oxidation reaction. The oxidation of AMP preferentially occurred on the β-lactam structure. The inherent mechanisms related to pH and oxygen conditions were firstly investigated, which could enhance the understanding of both oxidation and hydrolysis mechanisms in AMP degradation. This study not only has an important implication in predicting β-lactam antibiotic transformation and fate in natural environment but also benefits the developing of strategies of antibiotic control to reduce the environmental risk.
Afficher plus [+] Moins [-]Characterization of phosphorus forms in lake macrophytes and algae by solution 31P nuclear magnetic resonance spectroscopy
2016
Feng, Weiying | Zhu, Yuanrong | Wu, Fengchang | Meng, Wei | Giesy, John P. | He, Zhongqi | Song, Lirong | Fan, Mingle
Debris from aquatic macrophytes and algae are important recycling sources of phosphorus (P), which can result in continuing blooms of algae by recycling bioavailable P in the eutrophic lakes. However, knowledge of forms of P in aquatic macrophytes and algae and their contribution to internal loads of P in lakes is limited. Without such knowledge, it is difficult to develop appropriate strategies to remediate and or restore aquatic ecosystems that have become eutrophic. Therefore, in this work, P was extracted from six types of aquatic macrophytes and algae collected from Tai Lake of China and characterized by use of solution ³¹P-nuclear magnetic resonance (NMR) spectroscopy. When extracted by 0.5 M NaOH-25 mM EDTA, extraction recovery of total P(TP) and organic P(Pₒ) exceeded 90 %. Concentrations of Pₒ in algae and aquatic macrophytes were 5552 mg kg⁻¹ and 1005 mg kg⁻¹ and accounted for 56.0 and 47.2 % of TP, respectively. When Pₒ, including condensed P, was characterized by solution ³¹P-NMR Pₒ in algae included orthophosphate monoesters (79.8 %), pyrophosphate (18.2 %), and orthophosphate diester (2.0 %), and Pₒ in aquatic macrophytes included orthophosphate monoesters (90.3 %), pyrophosphate (4.2 %), and orthophosphate diester (5.5 %). Additionally, orthophosphate monoesters in algal debris mainly included β-glycerophosphate (44.1 %), α-glycerophosphate (13.5 %), and glucose 6-phosphate (13.5 %). Orthophosphate monoesters in aquatic macrophytes mainly included β-glycerophosphate (27.9 %), α-glycerophosphate (24.6 %), and adenosine 5′ monophosphate (8.2 %). Results derived from this study will be useful in better understanding nutrient cycling, relevant eutrophication processes, and pollution control for freshwater lakes.
Afficher plus [+] Moins [-]Removal rates of antibiotics in four sewage treatment plants in South India
2016
Prabhasankar, Valiparambil Prabhakaranunni | Joshua, Derrick Ian | Balakrishna, Keshava | Siddiqui, Iyanee Faroza | Taniyasu, Sachi | Yamashita, Nobuyoshi | Kannan, Kurunthachalam | Akiba, Masato | Praveenkumarreddy, Yerabham | Guruge, Keerthi S.
The occurrence and removal of seven selected pharmaceutical compounds (PCs) in sewage treatment plants (STPs) in South India were investigated. The PCs selected for this study were sulfamethoxazole (SMX), trimethoprim (TMP), chloramphenicol (CAP), erythromycin (ERY), naproxen (NPX), bezafibrate (BZF), and ampicillin (AMP). Wastewater samples were collected from inlet and outlet of the STPs during pre-monsoon, monsoon, and post-monsoon seasons to investigate the seasonal influences in occurrence and removal rates. The analytical method was based on simultaneous extraction of all target compounds by solid phase extraction (SPE), using a hydrophilic–lipophilic-balanced (HLB) sorbent followed by high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). The STP that catered exclusively to domestic wastewater had lesser concentrations of PCs compared to the STPs serving the combined hospital and domestic effluents. SMX was the dominant compound in all effluents with the highest concentration at 3.2 μg/L in the outlet of an STP. TMP and ERY were the other PCs present at higher concentrations in STP outlets (1 μg/L and 0–0.13 μg/L, respectively). Removal rates varied from 100 % for BZF to 60–100 % for SMX, CTX, and AMP.
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