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Use of Prosopis laevigata Seed Gum and Opuntia ficus-indica Mucilage for the Treatment of Municipal wastewaters by Coagulation-Flocculation

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Natural Resources 2012年第2期3卷 35-41页

作者： Luis G. Torres Sandra L. Carpinteyro-Urban Department of Bioprocesses Unidad Profesional Interdisciplinaria de Biotecnología UPIBI-Instituto Politécnico Nacional Mexico

Prosopis laevigata and Opuntia ficus-indica grow in arid and semiarid regions of Mexico and other countries. Both produce biopolymers with interesting characteristics from the rheological point of view as well as because of their coagulating-flocculating capabilities. Prosopis produce galactomannans inside the endosperm, very similar to those found in guar, locust bean, and tara gums. Opuntia sp. produces mucilage that contains polygalacturonic acid and five neutral sugars. Prosopis seed gum has not been proposed to be used as coagulant-flocculant before. In the case of Opuntia mucilage, some authors have suggested its use in the treatment of waters, using either the mucilage or the whole cladode powder. The use of these products in the treatment of municipal or even industrial wastewaters could give rise to diverse benefits. From the environmental point of view, treated waters with neither Fe nor Al, nor synthetic polymers would be obtained (with less toxicity risk). Besides, the produced sludges would be smaller in amount, with better biodegradability, and lower metals content. From the economical point of view, the use of these biopolymers would give an added value to the Opuntia and Prosopis culture in Mexico, helping small communities to enhance their incomes by producing environmental-friendly products. This work shows that both Prosopis galactomannan and Opuntia mucilage can be used to treat municipal wastewaters with an initial organic charge of about 827 mg/L as COD by the coagulation-flocculation process, with COD removals for the mesquite seed gum of up to 90% (pH 10, dose of 75 mg/L) and of 60% (pH 7, doses of 50 and 150 mg/L). In the case of mucilage, 65% of the initial COD was removed at pH 10 (dose of 50 mg/L). These figures are very promising for the treatment of wastewaters, with environmental-friendly products.

关键词： Biopolymers Coagulation Flocculation Opuntia ficus Mucilage Prosopis laevigata Seed Gum wastewaters

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Study on Cadmium Resistant-Bacteria Isolated from Hospital wastewaters

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Advances in Bioscience and Biotechnology 2014年第8期5卷 718-726页

作者： Benmalek Yamina Benayad Tahar Madour Lila Hacene Hocine Fardeau Marie Laure Laboratoire de Microbiologie IRD Aix-Marseille Université Université du Sud Toulon-Var CNRS/INSU IRD Marseille France Laboratoire de Microbiologie Département de BCM Faculté des sciences biologiques Université des Sciences et de Technologie Houari Boumediene Alger Algerie

In hospital, a variety of substances are in use for medical purposes as diagnostics and researches. Among them, heavy metals which are not biodegradable by chemical reactions have bioaccumulation properties. Cadmium is a toxic pollutant that enters hospital wastewaters by different ways. However, isolated bacteria from hospital effluents have high resistance to antimicrobial agents and therefore the ability to uptake cadmium and other metals. So, their use is recommended for wastewater bioremediation. In this study, twelve cadmium-resistant bacteria were isolated from hospital wastewaters and identified. The cadmium-resistant isolates characterized include both Gram-negative [75%] and Gram-positive [25%]. The Minimum Inhibitory Concentration of hospital wastewaters isolates was determined in solid media and was ranged from 250 to 950 micrograms/milliliters. All the isolates showed co-resistance to zinc and mercury. They were also antibiotic resistant and tolerated up a significant concentration of NaCl. The cadmium-resistant species Klebsiella pneumoniae and Pseudomonas aeruginosa were the most resistant to cadmium. The species Klebsiella pneumonia also resists to the highest concentrations of zinc and mercury. The results of toxicity tests on Vibrio fischeri, showed that the DI50 [15 min] as low as 0.07 carried away 50% luminescence inhibition.

关键词： Antibiotics Cadmium-Resistant Bacteria Hospital wastewaters

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The study of biological activity of transformation products of diclofenac and its interaction with chlorogenic acid

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Journal of Environmental Sciences 2020年第5期32卷 128-141页

作者： Marzena Matejczyk Piotr Ofman Katarzyna Dabrowska Renata Swislocka Wlodzimierz Lewandowski Bialystok University of Technology Faculty of Civil Engineering and Environmental SciencesDepartment of ChemistryBiology and Biotechnology15-341BialystokPoland Bialystok University of Technology Department of Environmental Engineering TechnologyBialystok15-341Poland Waclaw Dabrowski Institute of Agricultural and Food Biotechnology Department of Microbiology02-532WarsawPoland

In the present work we compared the biological activity of DCF,4’-OHDCF and 5-OHDCF as molecules of most biodegradation pathways of DCF and selected transformation products(2-hydroxyphenylacetic acid;2,5-dihydroxyphenylacetic acid and 2,6-dichloroaniline)which are produced during AOPs,such as ozonation and UV/H2 O2.We also examined the interaction of DCF with chlorogenic acid(CGA).CGA is commonly used in human diet and entering the environment along with waste mainly from the processing and brewing of coffee and it can be toxic for microorganisms included in activated sludge.In the present experiment the evaluation of following parameters was performed:E.coli K-12 cells viability,growth inhibition of E.coli K-12 culture,LC50 and mortality of Chironomus aprilinus,ge no toxicity,sodA promoter induction and ROS generation.In addition the reactivity of E.coli SM recA:luxCDABE biosensor strain in wastewater matrices was measured.The results showed the influence of DCF,4’-OHDCF and 5-OHDCF on E.coli K-12 cells viability and bacteria growth,comparable to AOPs by-products.The highest toxicity was observed for selected,tested AOPs by-products,in comparison to the DCF,4’-OHDCF and 5-OHDCF.Genotoxicity assay indicated that 2,6-dichloroaniline(AOPs by-product)had the highest toxic effect.The oxidative stress assays revealed that the highest level of ROS generation and sodA promoter induction were obtained for DCF,4’-OHDCF and 5-OHDCF,compared to other tested compounds.We have also found that there is an interaction between chlorogenic acid and DCF,which resulted in increased toxicity of the mixture of the both compounds to E.coli K-12,comparable to parent chemicals.The strongest response of E.coli SM biosensor strain with recA:luxCDABE genetic construct in filtered treated wastewaters,comparable to control sample was noticed.It indicates,that E.coli SM recA:luxCDABE biosensor strains is a good tool for bacteria monitoring in wastewater environment.Due to toxicity and biological activity of tested DCF transformation products,

关键词： Diclofenac Biodegradation Chlorogenic acid Advances oxidation processes (AOPs) wastewaters Microbial biosensors

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Vacuum promotes metabolic shifts and increases biogenic hydrogen production in dark fermentation systems

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Frontiers of Environmental Science & Engineering 2016年第3期10卷 513-521页

作者： Haifa RAJHI Daniel PUYOL Mirna C. MARTiNEZ Emiliano E. DLAZ Jose L. SANZ Department of Molecular Biology University Autonoma of Madrid Madrid 28049 Spain Section of Chemical Engineering University Autonoma of Madrid Madrid 28049 Spain MYGEN Laboratory Cantoblanco Madrid 28049 Spain

The successful operation of any type of hydrogen-producing bioreactor depends on the performance of the microorganisms present in the system. Both substrate and partial gas pressures are crucial factors affecting dark fermentation metabolic pathways. The main objective of this study was to evaluate the impact of both factors on hydrogen production using anaerobic granular sludge as inoculum and, secondly, to study the metabolic shifts of an anaerobic community subjected to low partial gas pressures. With this goal in mind, seven different wastewater （four synthetic media, two industrial waste- water, and one domestic effluent） and the effect of applying vacuum on the systems were analyzed. The application of vacuum promoted an increase in the diversity of hydrogen-producing bacteria, such as Clostridium, and promoted the dominance of acetoclasticover hydrogenotrophic methanogens. The application of different media promoted a wide variety of metabolic pathways. Nevertheless, reduction of the hydrogen partial pressure by application of vacuum lead to further oxidation of reaction intermediates irrespective of the medium used, which resulted in higher hydrogen and methane production, and improved the COD removal. Interestingly, vacuum greatly promoted biogenic hydrogen production from a real wastewater, which opens possibilities for future application of dark fermentation systems to enhance biohydrogen yields.

关键词： dark fermentation biohydrogen wastewaters vacuum

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Composite Activated Carbon from Canarium schweinfurthii/Polyethylene Terephthalate: Adsorption Test of Rhodamine B Dye Removal in Aqueous Solution

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Journal of Materials Science and Chemical Engineering 2023年第11期11卷 75-105页

作者： Gadjui Youatou Boris Ankoro Naphtali Odogu Lekene Ngouateu René Blaise Kouotou Daouda Ndi Julius Nsami Ngomo Horace Manga Ketcha Joseph Mbadcam Applied Physical and Analytical Chemistry Laboratory Department of Inorganic Chemistry Faculty of Science University of Yaoundé I Yaoundé Cameroon Department of Chemistry Faculty of Science University of Buea Buea Cameroon

The present work deals on one hand with the valorization of wastes plastics, polyethylene terephthalate (PET) and Canarium schweinfurthii (CS) for the preparation of polyethylene terephthalate activated carbon (PETAC) and Canarium schweinfurthii/polyethylene terephthalate activated carbon (CS/PETAC). These adsorbents, on the other hand, were used for removal Rhodamine B (RhB) in an aqueous solution. PET and CS precursors were subjected to thermogravimetric analysis (TGA) and differential scanning colorimetry (DSC). Meanwhile PETAC and CS/PETAC were characterized using scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), X-ray fluorescence (XRF), Fourier transformed infrared spectroscopy (FT-IR) and nitrogen adsorption/desorption (N2-BET). The N2-BET results revealed an increase of the specific surface area from 6.75 m2/g to 1282.0 m2/g for PETAC and CS/PETAC. The results of characterization indicated the key role played by plastic wastes to enhance the structural and functional properties of CS/PETAC. The RhB removal from the aqueous solution onto PETAC and CS/PETAC was found to be independent of pH, with an optimal contact time of RhB removal within 10 min for materials. The non-linear adsorption isotherm data for the adsorption process showed that the Langmuir and Freundlich models best fitted the RhB adsorption onto PETAC meanwhile only the Freundlich adsorption isotherm gave the best fit for CS/PETAC according to the correlation coefficient value closed to unity. The pseudo-first and pseudo-second-order kinetic models best described the RhB dye removal on both adsorbents. Additionally, the Elovich model confirmed that chemisorption was the main mechanism followed. These findings proved that CS seeds and PET wastes are low-cost precursors that should be given an added value by transforming them into an outstanding carbon material for dye removal in liquid effluent.

关键词： Activated Carbon Rhodamine B Canarium schweinfurthii Plastics Wastes Pollution wastewaters

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Synthesis and photocatalytic properties of Sn-TiO_(2) nanomaterials

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Journal of Advanced Dielectrics 2020年第1期10卷 129-138页

作者： E.M.Bayan T.G.Lupeiko L.E.Pustovaya M.G.Volkova Department of Chemistry Southern Federal University Rostov-on-Don 344090 Russia Don State Technical University Rostov-on-Don 344000 Russia

Sn-doped TiO_(2) nanomaterials were synthesized by sol-gel method.It was shown the phase compositions and phase transitions change with the introduction of different tin amounts(0.5-20 mol.%).X-ray powder diffraction was used to study the effect of different tin amounts on the anatase-rutile phase transition.It was found that the introduction of ions increases the thermal stability of anatase modifications.The material’s photocatalytic activity was studied in reaction with a model pollutant(methylene blue)photodegradation under UVand visible light activation.The best photocatalytic properties were shown for material,which contains 5 mol.%of Sn.

关键词： Nanomaterial titanium dioxide photocatalysis anatase wastewaters tin

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Occurrence and ecological risk assessment of pharmaceutical products in the Kadicha river in Lebanon

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Emerging Contaminants 2021年第1期7卷 196-203页

作者： Fatme Merhabi Elena Gomez Nancy Ariza Castro Helmieh Amine David Rosain Jalal Halwani Helene Fenet Hydrosciences Montpellier IRDCNRSUniversity of MontpellierMontpellierFrance Water&Environment Science Laboratory Faculty of Public Health(FSP III)Lebanese UniversityTripoli1300Lebanon Escuela de Química Instituto Tecnologico de Costa RicaCartago 159-7050Costa Rica

Contamination of aquatic systems with pharmaceutical products represents a rising concern.The Kadicha river in Northern Lebanon is an illustrative example of a small Mediterranean river affected by rapid urbanization and population growth.This paper reports the first study on occurrence and ecological risk assessments on selected pharmaceuticals and their metabolites within the Kadicha river.For this purpose,surface water samples were collected over two sampling campaigns from twelve sites impacted by urban,rural,and mixed land uses(residential and agricultural zones)within the Kadicha river basin.Among the studied pharmaceuticals,six compounds(carbamazepine,diclofenac,acetaminophen,sulfamethoxazole,ofloxacin,and atenolol)were detected with detection frequencies and concentrations that vary according to the sampling sites.Carbamazepine was the most frequently detected compound and showed the highest concentrations(not detected-290 ng/L).The presence of pharmaceuticals carbamazepine,ofloxacin(not detected-190 ng/L),and atenolol(not detected-93 ng/L)was related to raw wastewater inputs in the water body,while the presence of sulfamethoxazole(not detected-23 ng/L)was associated with its usage in specific sites with livestock activity.Besides,the presence of acetaminophen(not detected-242 ng/L)and diclofenac(not detected-1055 ng/L)can be affected by their degradation properties in river waters.The highest concentrations were observed in the urbanized downstream area,while the lowest concentrations were within the rural upstream area.Thus,the urbanized downstream area presents the highest potential risks for aquatic species.Moreover,ofloxacin may pose high ecotoxicological risks in this watershed.The levels of contamination with pharmaceuticals do not exceed the concentrations reported in the literature.Furthermore,the levels of carbamazepine,diclofenac,and acetaminophen were more similar to sites receiving raw wastewaters,while the concentration levels of sulfamethoxazole,ofloxacin,and atenolol were more similar to s

关键词： Kadicha river Pharmaceuticals Surface waters wastewaters Potential risk Urbanization

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Biodegradation of Toxic Compounds in Olive Mill Wastewater by a Newly Isolated Potent Strain: <i>Aspergillus niger</i>van Tieghem

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Journal of Water Resource and Protection 2013年第8期5卷 768-774页

作者： Fatiha Hanafi Mohammed Mountadar Samira Etahiri Mohamed Fekhaoui Omar Assobhei Département de Zoologie et Ecologie Animale Institut Scientifique Université Mohammed V-Agdal Rabat Morocco Laboratoire de Biotechnologies Marine et de l’Environnement Faculté des Sciences Université Chouaib Doukkali El Jadida Morocco Laboratoire de Biotechnologies Marine et de l’Environnement Faculté des Sciences Université Chouaib Doukkali El Jadida Morocco Unité de Chimie Analytique et Sciences de l’Environnement Faculté des Sciences Université Chouaib Doukkali El Jadida Morocco

Thirty-two strains isolated from olive oil production plants were screened for their tolerance to the polyphenols and their ability to grow in olive oil mill wastewaters (OMW). An Ascomycete isolate that grew best on OMW was selected for further study to evaluate its effect on removal of organic pollutants, phenolic compounds and OMW toxicity. This strain was identified by DSMZ as Aspergillus niger van Tieghem. The growth of Aspergillus niger van Tieghem on stored OMW decreased pH and led to the reduction of phenolic compounds with a resultant discoloration of OMW and significant reduction of chemical oxygen demand (COD), in proportion to the dilution of OMW. The reduction of the COD, phenolics and color exceeded 50%. Tannase, the enzyme detected in the growth medium of Aspergillus niger van Tieghem was produced during primary metabolic growth. The maximal enzyme activity attaining 0.68 EU/ml was achieved in 3rd days of cultivation. The phytotoxicity of the stored OMW was reduced to about 40% after 4 days’ incubation with Aspergillus niger van Tieghem.

关键词： Aspergillus niger van Tieghem Olive Oil Mill wastewaters Phenolic Compounds Tannase Toxicity

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Physic-Chemical Evaluation of Urban Wastewater of the Town of Sidi Kacem

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Computational Water, Energy, and Environmental Engineering 2014年第1期3卷 30-35页

作者： Omar El Rhaouat Imane El Kherrati Fatiha El khayyat Hamid Chiguer Karima Ezziani Abdalsalam Ibeda Mostafa Fareh Youssef Saidi Khadija El Kharim Driss Belghyti Laboratory of Environment and Renewable Energies Faculty of Science University Ibn Tofail Kenitra Morocco National Office of Drinking Water Rabat Morocco Office of Technical Studies Rabat Morocco

The goal of this study is the evaluation of pollution by the physic-chemical characterization of urban wastewaters discharged in the river R’dom of the town Sidi Kacem. The motivation of this study is multiple firstly to give an answer to the choice of methods of treatment of raw sewage and secondly to raise awareness of the pollution of the river R’dom who is a source of irrigation in the region. The physic-chemical analyses were carried out on the level of the collector 1 (domestic collector of the Zaouia District) and that of collector 2 (domestic collector of the allotments Thami Amar, road of Tangier and Saada), during the year 2012 at the same time “in situ” and at the Laboratory of Environment (Faculty of Sciences Kenitra). The polluting load out of organic matter (DBO5, DCO, MES), out of mineral matter (Cl-, Ca2+, Mg2+, K+, , Na+) and out of nitrogenized matter (, , Nitrogenize total) was more important, except for the temperature and of the pH which are in conformity with the Moroccan standards of rejection. Ratios DCO/DBO5, DBO5/DCO and MES/DBO5 inform about the biodegradability of these effluents and permitted choice of the suitable treatment process. Indeed, results obtained show that the domestic effluents exceed the national standards of rejection, which requires an intervention of the competent jurisdictions in order to preserve the public health, to protect the environment and install an efficient sewage treatment plant to ensure a sustainable development.

关键词： wastewaters Physic-Chemistry Pollution Sidi Kacem Morocco

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Coliforms and Helminth Eggs Removals by Coagulation-Flocculation Treatment Based on Natural Polymers

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Journal of Water Resource and Protection 2013年第11期5卷 1027-1036页

作者： Evelyn Zamudio-Pérez Neftalí Rojas-Valencia Isaac Chairez Luis Gilberto Torres Bioprocesess Department UPIBI-Instituto Politécnico Nacional Barrio la Laguna Ticomán Mexico Engineering Institute UNAM Environmental Engineering Department Coyoacán Mexico

Wastewater from a municipal wastewater treatment plant (Mexico) was treated by a coagulation-flocculation using natural gums. The residual water was characterized in terms of organic load, and biological contaminants, i.e. total Coliforms (TC), fecal Coliforms (FC) and helminth eggs (HE). The sample has values of 2.8 × 107 MPN/100 ml, 8.48 × 106 MPN/100 ml and 470 HE/L is regarded to TC, FC and HH, respectively. The HE identified in the wastewaters were Diphyllobothrium latum, Ascaris lumbricoides, Hymenolepis nana and Toxocara canis. From several gums, Hydroxypropyl triammonium chloride guar gum (HPTAC-guar) was selected as the most adequate coagulant-flocculant for the class of municipal wastewater (MWW). A diminution of 82% for TC, 94% for FC and 99% for HE was obtained. Besides, the reduction of chemical oxygen demand (COD) and turbidity removals were 46% and 39% respectively. The natural gum mixed with Ca(OH)2, obtained removals of 52% for TC, 100% for HE, 47% for COD and 30% for turbidity.

关键词： Coagulation Fecal Coliforms Flocculation Helminth Eggs Total Coliforms wastewaters

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