► The removal of C.I. Reactive Red 43 dye by electrocoagulation (EC) was studied. ► Response surface methodology was utilized for optimizing and modeling EC process. ► The results confirmed ...degradation of dye was occurrence during EC using iron anode. ► The degradation by-products were identified by GC–MS technique.
The optimization and modeling of the electrocoagulation process which conducted by means of iron (EC-Fe) and aluminum (EC-Al) anodes, in the removal of C.I. Reactive Red 43 were performed through the response surface methodology (RSM). Moreover, the occurrence of possible destructive reactions during both EC-Fe and EC-Al processes was investigated using UV–Vis spectrometry, total organic carbon (TOC) and GC–MS analyses. The electrocoagulation experiments were carried out in a monopolar batch reactor using two anodes and two cathodes in parallel connections. Current density, time, pH and chloride concentration were considered as input variables for RSM. The analysis of variance revealed a high coefficient of determination (REC-Fe2=0.981 and REC-Al2=0.934) between experimental removal efficiency and predicted one by RSM developed models. The optimum conditions proposed by RSM to reach the maximum RR43 removal through the EC-Fe were different from the ones proposed for the EC-Al. At the optimum conditions, the removal efficiency of dye was more than 99% for both processes, whereas 90.58% and 98.37% of initial TOC concentration decreased during EC-Fe and EC-Al processes, respectively. The analyses results confirmed that beside sweep flocculation mechanism, known as the main removal mechanism, the degradation of dye was occurred during EC-Fe as a minor pathway.
Bacterial strains D11, E1 and E2 isolated from petroleum-contaminated soils were found to be members of Acinetobacter genus revealed by 16S rRNA gene sequence analysis and phenotypic characteristics. ...After incubation for 5 days, about 43, 9 and 12 % of total petroleum hydrocarbons of crude oil were degraded by strains D11, E1 and E2, respectively, and determined by GC?MS analysis. Moreover, about 70 and 76 % of single hydrocarbon hexadecane was degraded by the strains D11 and E1 after 3 days of short incubation time, respectively, while the strain E2 degraded about 48 % of single hydrocarbon pentadecane. By using PCR-based method, gene sequences of the strains D11 and E2 showed similarity to alkane 1-monooxygenases from Acinetobacter sp. BUU8 alkM with 93.06 and 92.72 %, respectively, while the sequence similarity of strain E1 was 95.84 % to Acinetobacter sp. 826659. The present study of hydrocarbon biodegradation by Acinetobacter strains may provide a good advantage in bioremediation process.
•SAMBRs can operate at very low HRTs (1h), and are very tolerant to hydraulic shocks.•SMP were 14±2mgCOD/L (feed 544mg/L) at steady state, but fluctuated during shocks.•GC–MS with solid phase ...extraction identified 120 compounds in the SAMBR effluent.•Microbially produced N-butyl-benzenesulfonamide/cyclooctasulfur found during shocks.
This study investigated the performance of a submerged anaerobic membrane bioreactor (SAMBR) fed with synthetic wastewater (544±22mgCOD/L) operating at different hydraulic retention times (HRTs-12h, 8h, 6h, 4h, 2h, and 1h) at both steady state, and under transient load conditions (2 and 1h), and the SMPs produced under these conditions. COD removal at decreasing HRTs (12h, 8h, 6h, 4h, and 2h) was high (>94%), but decreased to 80% when operating at 1h HRT. VFAs accumulated when the HRT was decreased to 2h and 1h, accounting for 69% and 89% of the effluent COD, respectively. Effluent SMPs accounted for an average of 14±2mgCOD/L at steady state, but this fluctuated more during transient conditions (12±6mgCOD/L). The COD equivalent of dissolved methane in the effluent was 17% at 4h HRT, exceeding the saturation value of methane. Low MW compounds were identified using gas chromatography–mass spectrometry (GC–MS), with solid phase extraction (SPE) as the pre-treatment. 120 compounds were identified in the effluent at steady state, and were alkanes (39), alkenes (3), esters (11), alcohols (7), nitrogenated compounds (11), phenols (11), and others (9). Increases in cyclooctasulfur, N-butyl-benzenesulfonamide, alkanes, 1-naphthalenol, camphor, 2-methylphenol, and (Z)-9-octadecenamide were also found during transient conditions, and these compounds were not found in the feed; hence it is possible that these compounds were produced by microorganism as by-products from substrate utilization.
Headspace solid-phase microextraction/gas chromatography-mass spectrometry (HS-SPME/GC-MS) analysis combined with 'relative odour activity value (ROAV)' was used to monitor changes in key volatile ...compounds in peanut oil, soybean oil, rapeseed oil, and linseed oil during ambient storage. Volatile composition and oxidation process were compared among edible oil samples. The differences in the volatile contents of edible oils led to their characteristic flavour. Aldehydes featured a relatively high content and low odour threshold and mainly contributed to the flavour of edible oils. The key flavour compounds included pentanal, hexanal, octanal, nonanal, trans-2-heptenal, and benzaldehyde, which are important oxidative degradation products of oleic acid and linoleic acid. The formation of key volatile oxidation compounds was affected by different oxidation processes during ambient storage. Certain aldehydes increased with oxidation level, whereas other aldehydes initially increased then decreased. Correlation analysis showed that the concentrations of several volatile compounds progressively increased during oxidation. The key volatile oxidation compounds formed during oil storage at ambient temperature are partly different from those generated at high temperatures. Volatile oxidation compounds can be a marker for monitoring the oxidation degree of edible oils during ambient storage.
This article contains the result of the first study on the chemical composition of six methanol extracts of different plant parts of the Gypsophila pilulifera, which were grown in vitro and ...transferred to field conditions according to their distribution location. The methanol extracts of the leaves, branches, and roots of the G. pilulifera were obtained using the maceration method. All methanol extracts were derivatized with trimethylsilyl (-TMS) for gas chromatography-mass spectrometry (GC-MS) analysis. Fatty acid derivatives were the dominant group in all the extracts. Palmitic acid, (Z,Z)− 9,12-octadecadienoic acid, and stearic acid were common fatty acids in all extracts. Sterols were detected in all methanol extracts. The predominant sterol was (3β,22E)-Ergosta-7,22-dien-3-ol in the analyzed extracts. The determination of sterol compounds contributes to greater knowledge about the G. pilulifera and brings more attention to this plant species. G. pilulifera is an endemic and critically endangered (CR) species. The plant has potential use in different areas, especially in the pharmaceutical industry. In the current study, the chemical content of the underground and aboveground parts of G. pilulifera produced under in vitro conditions from the seeds collected from two different locations in nature was investigated comparatively according to their locations for the first time.
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•The parts of Gypsophila pilulifera were in vitro produced from meristem and seed explants.•Sterols were detected in all the methanol extracts.•(3β,22E)-Ergosta-7,22-dien-3-ol was the predominant sterol in analyzed extracts.•Fatty acid derivatives were the dominant group in all the extracts.
In this study, a comprehensive investigation was conducted to use municipal sewage sludge (MSS) as a promising feedstock for bioenergy production via pyrolysis process. Using thermogravimetric ...analysis (TGA), MSS was subjected to thermal decomposition experiments at four different heating rates of 5, 10, 30 and 50 °C/min. TGA curves were divided into three distinctive stages, namely drying zone (T ≤ 200 °C), active pyrolysis zone (200 < T < 600 °C), and char decomposition zone (T ≥ 600 °C). Moreover, the data were used to analyze thermo-kinetic parameters through Flynn-Wall-Ozawa (FWO), Kissenger-Akahira-Sunose (KAS), and Starink methods, where the average values of Ea (126.62–136.92 kJ/mol), Gibbs free energy (159.19–159.61 kJ/mol), and calculated high heating value (HHV, 16.47 ± 0.03 MJ/kg) showed the considerable bioenergy potential of the low-cost biomass. The low difference between Ea and ΔH (~ 5 kJ/mol) showed that product formation was favorable during pyrolysis. In addition, for the first time, the comparative study of the results predicted from support vector regression (SVR) model and the experimental data, showed a satisfactory agreement (R2 > 0.9999) and accurate results regarding different train-test data categories. Further employed was Pyrolysis–Gas Chromatography/Mass Spectroscopy (Py-GC/MS) at 700 °C to characterize the potential chemical products, which indicated the presence of a range of aromatic and aliphatic hydrocarbons, nitrogen-containing compounds, alcohol, furans and sulfur compounds. Finally, three alternative scenarios associated with the planned project were presented and techno-socio-economic assessment (TSEA) of the alternative scenarios were evaluated, for the first time, by means of economic indexes and considering social aspects. Net present value (NPV) of all alternative scenarios of the pyrolysis plant over the 20-year plant lifetime was positive compared to the base case, indicating that the project was feasible. Sensitivity analysis of the optimistic scenario showed that the profitability of pyrolysis plant was highly dependent on bio-oil selling price and total production cost.
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•Thermo-kinetics parameters of MSS pyrolysis were deciphered.•SVR model indicated good applicability to predict remaining mass.•Py-GC/MS analysis was conducted to characterize the potential chemical products.•Three alternative scenarios were designed for techno-socio-economic assessment.•Economic sensitivity analysis was carried out to identify most important variables.
Table olives are one of the most important traditional fermented vegetables in Europe and their world consumption is constantly increasing. Conservolea and Kalamàta are the most important table ...olives Greek varieties. In the Greek system, the final product is obtained by spontaneous fermentations, without any chemical debittering treatment. This natural fermentation process is not predictable and strongly influenced by the physical-chemical conditions and by the presence of microorganisms contaminating the olives. Natural fermentations of Conservolea and Kalamàta cultivars black olives were studied in order to determine microbiological, biochemical and chemical evolution during the process. Following the process conditions generally used by producers, in both cultivars, yeasts were detected throughout the fermentation, whereas lactic acid bacteria (LAB) appeared in the last staged of the process. A new optimized specific protocol was developed to select autochthonous yeast and LAB isolates that can be good candidates as starters. These microorganisms were pre-selected for their ability to adapt to model brines, to have beta-glucosidase activity, not to produce biogenic amines. Chemical compounds deriving by microbiological activities and associated to the three different phases (30, 90 and 180 days) of the fermentation process were identified and were proposed as chemical descriptors to follow the fermentation progress.
•A microbiological and chemical evolution of black olives fermentation is proposed.•A new protocol for yeast and LAB selection as autochthonous starter is developed.•Chemical descriptors can be associated to three different phases of fermentation.
The aim of this investigation was to find enzymes and metabolites involved in ß Cypermethrin pesticide degradation. The continuous usage of chemical pesticide for rapid agriculture activities leads ...to the major cause of soil pollution. In this study, Bacillus cereus, a bacterium isolated from the BT cotton cultivated and pesticide contaminated soil has the efficiency to degrade ß Cypermethrin, a synthetic pyrethroid insecticide used in most crop cultivations. Standard lab scale bioremediation process was followed on mineral salt agar medium (MSM) enriched with ß Cypermethrin. Initially, the fragmentation of ß Cypermethrin was confirmed by Thin-Layer Chromatography (TLC), which revealed the existence of metabolites with Retention Factor (RF) value range of 0.47 and 0.71, corresponding to standard samples of 3-PBA and phenol. Later, SDS-PAGE analysis was carried out to identify enzymes involved in the biodegradation, and a protein of size 56 kDa molecular weight was identified and confirming the presence of Pyrethroid hydrolase. The fragmented ß Cypermethrin metabolite was reconfirmed by GC–MS analysis, which confirmed the degradation of ß Cypermethrin. The peaks of metabolites were recognized as Benzylamine and related components, these are derivatives of ß cypermethrin in degraded by B. cereus. Hence, the study concludes that, the 56 kDa molecular weight Pyrethroid hydrolase synthesized by B. cereus has the efficiency to metabolize the ß Cypermethrin pesticide. Thus, the B. cereus could be most suitable agent for chemical pesticide degradation.
Gastrointestinal disorders are among the most common diseases that cause discomfort to people who are affected. In Morocco, aromatic and medicinal plants are widely used to calm these pains and ...eliminate their symptoms. Among these plants, Artemisia campestris L. which is used in eastern Morocco to treat digestive system problems.
Our study aimed to experimentally verify the traditional use of this plant by evaluating the myorelaxant and antispasmodic effects of the essential oil of Artemisia campestris L. (EOAc).
Gas Chromatography-Mass Spectrometry analysis (GC-MS) was performed to identify the compounds present in the EOAc. Then, these molecules were subjected to the in silico study for molecular docking. The myorelaxant and antispasmodic evaluation of the EOAc were tested in vitro on an isolated rabbit and rat jejunum mounted on an organ bath. Then, an isotonic transducer connected to an amplifier recorded the graph related to intestinal contractility.
GC-MS analysis of the essential oil of Artemisia campestris L. showed the presence of m-Cymene (17.308%), Spathulenol (16.785%), β Pinene (15.623%), α Pinene (11.352%), α.-Campholenal (8.848%) as main constituents. The EOAc gave a dose-dependent and reversible myorelaxant effect on the spontaneous contractions of jejunum isolated from rabbits, with an IC50 equal to 72.16 ± 15.93 μg/mL. This effect did not occur through adrenergic receptors. The EOAc has an antispasmodic effect on the contractions of rat jejunal induced by a medium with low (25 mM) or high concentration (75 mM) of KCl, and carbachol 10−6 M. The obtained inhibitory effects are comparable to those of a non-competitive antagonist of cholinergic receptors. The major compounds of EOAc allowed the establishment of a relationship between these phytoconstituents and the antispasmodic effect found by the EOAc. The obtained results are also supported by a docking study.
The obtained results confirm favorably the use of Artemisia campestris L. in traditional Moroccan medicine for the treatment of digestive tract illness, which gives us a new route to valorize the effects obtained by a phytomedicine specific for the digestive tract.
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•Essential oil of Artemisia campestris L. (EOAc) showed the presence of m-Cymene , Spathulenol , β Pinene , and α Pinene.•The EOAc gave a dose-dependent and reversible myorelaxant effect on the spontaneous contractions of rabbit jejunum.•The EOAc had an antispasmodic effect on the contractions of rat jejunum induced byKCl, and Carbachol.•The inhibitory effects obtained by EOAc are comparable to those of a non-competitive antagonist of cholinergic receptors.•Spathulenol was the best component among those of EOAc that could bind to voltage-gated Ca2+ and Muscarinic receptor.
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