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Human APOBEC3A (A3A) is a nucleic acid-modifying enzyme that belongs to the cytidine deaminase family. Canonically, A3A catalyzes the deamination of cytosine into uracil in single-stranded DNA, an activity that makes A3A both a critical antiviral defense factor and a useful tool for targeted genome editing. However, off-target mutagenesis by A3A has been readily detected in both cellular DNA and RNA, which has been shown to promote oncogenesis. Given the importance of substrate discrimination for the physiological, pathological, and biotechnological activities of A3A, here we explore the mechanistic basis for its preferential targeting of DNA over RNA. Using a chimeric substrate containing a target ribocytidine within an otherwise DNA backbone, we demonstrate that a single hydroxyl at the sugar of the target base acts as a major selectivity determinant for deamination. To assess the contribution of bases neighboring the target cytosine, we show that overall RNA deamination is greatly reduced relative to that of DNA, but can be observed when ideal features are present, such as preferred sequence context and secondary structure. A strong dependence on idealized substrate features can also be observed with a mutant of A3A (eA3A, N57G) which has been employed for genome editing due to altered selectivity for DNA over RNA. Altogether, our work reveals a relationship between the overall decreased reactivity of A3A and increased substrate selectivity, and our results hold implications both for characterizing off-target mutagenesis and for engineering optimized DNA deaminases for base-editing technologies.

This study evaluated the capacity of a rock phosphate for the adsorption of organic dyes methylene blue MB and methyl orange MO in aqueous solution, in order to minimize the impact of these dyes on the environment. The physicochemical characterization of natural phosphates (NP) shows that its mineralogy is carbonate-fluorapatite, calcite and quartz, as demonstrated by X-ray diffraction. An infrared (IR) analysis completed the structural study by confirming the characteristic bands of a carbonated fluorapatite type B. The influence of adsorbent dose, pH, initial concentration and temperature of the dye solution on adsorption onto NP was studied. The experimental results show that MB is adsorbed almost entirely at an adsorbent dose of 1 g/L and at a more basic pH and that the Langmuir model describes its isotherm well. For MO, adsorption is performed at acidic pH, such that discoloration reaches 60% at pH 4 and NP adsorbent dose of 10 g/L. The maximum adsorbed amounts of MB (pH=9) and MO (pH=4) were found to be 9.54 and 1.09 mg/g, respectively. The kinetic data were analyzed to show that the pseudo-second-order model seems to be the most appropriate to describe the adsorption dynamics of both dyes on the naturel phosphate. The thermodynamic results show that the adsorption is endothermic for MB and exothermic for MO. So, rock phosphate shows a good potential as a sorbent for cationic dyes removal from wastewater.

DNA deaminase enzymes play key roles in immunity and have recently been harnessed for their biotechnological applications. In base editors (BEs), the combination of DNA deaminase mutator activity with CRISPR-Cas localization confers the powerful ability to directly convert one target DNA base into another. While efforts have been made to improve targeting efficiency and precision, all BEs to date utilize a constitutively active DNA deaminase. The absence of regulatory control over promiscuous deaminase activity remains a major limitation to accessing the widespread potential of BEs. Here, we reveal sites that permit splitting of DNA cytosine deaminases into two inactive fragments, whose reapproximation reconstitutes activity. These findings allow for the development of split-engineered base editors (seBEs), which newly enable small-molecule control over targeted mutator activity. We show that the seBE strategy facilitates robust regulated editing with BE scaffolds containing diverse deaminases, offering a generalizable solution for temporally controlling precision genome editing.

Ce travail s'inscrit dans le contexte global de valorisation de la biodiversité des plantes aromatiques du Sénégal. L’objectif de l’étude était de déterminer la composition chimique d’huiles essentielles (HE) de Mentha arvensis L. et d’évaluer leurs activités antioxydante et insecticide. A cet effet, des feuilles de M. arvensis ont été récoltées dans la région de Dakar (Sénégal) et séchées à l'ombre puis leurs HE extraites par entrainement à la vapeur d'eau. Les HE obtenues ont été analysées par chromatographie en phase gazeuse (CPG) couplée à un détecteur à ionisation de flamme (FID) et un spectromètre de masse (MS). L’activité antioxydante des HE a été évaluée par la méthode d’inhibition du radical 2,2-diphényl-1-picrylhydrazyl (DPPH) tandis que l’activité insecticide a été testée par fumigation contre Sitophilus zeamais (Motsch.). Les résultats ont montré que les HE contiennent principalement du menthol (68,4%), de l’acétate de menthyle (16,9%) et de la menthone (5,0%). Leur activité antioxydante augmente avec la concentration, soient 38%, 57% et 73% d’inhibition respectivement pour 10, 25 et 50 mg/ml ; la CI50 est de 19,5 mg/ml. Les huiles présentent aussi une activité insecticide. Cette dernière bien qu’étant faible après 24 heures, augmente fortement au bout de 48 heures avec une mortalité maximale de 92%. Cette mortalité atteint des maximums de 98% pour 5 et 25 μl et 100% pour 50 et 75 μl après 72 heures. English title: Antioxidant and insecticidal activities of essential oils of Mentha arvensis L. from Senegal This work is part of the global context of valorization of the biodiversity of aromatic plants from Senegal. The aim of the study is to determine the chemical composition of essential oils (EOs) of Mentha arvensis L. and to evaluate their antioxidant and insecticidal activities. For this purpose, leaves of M. arvensis were harvested in Dakar region, Senegal and dried in the shade. EOs were extracted by steam distillation from dried leaves and analyzed by gas chromatography (GC) coupled to a flame ionization detector (FID) and a mass spectrometer (MS). The antioxidant activity of EOs was assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method while the insecticidal activity was tested by fumigation against Sitophilus zeamais (Motsch.). The results revealed that EOs were dominated by menthol (68.4%), menthyl acetate (16.9%) and menthone (5.0%). The antioxidant activity assay showed that the inhibition increased with the concentration: 38%, 57% and 73% for 10, 25 and 50 mg/ml, respectively; the IC50 was of 19.5 mg/ml. The oils were also effective as insecticide. Mortalities were low after 24 hours and increased strongly after 48 hours with a maximum of 92%. They reached a maximum of 98% for 5 and 25 μl and 100% for 50 and 75 μl after 72 hours.

Background Adansonia digitata (L) fruit has a multi-purpose function one among many, is the antioxidant activities of the fruit by preventing oxidative stress. The effect of Adansonia digitata (L) fruit on lead-induced liver and kidney damage is not clear. Hence, the study was aimed to assessed the protective role of Adansonia digitata (L) fruits against lead acetate induced changes in the liver and kidney function test parameters and the histology of both organ in experimental rats. The rats were divided into five groups with five rats each. All the rats were administered with respective assigned treatment once daily for 6 weeks. Rats in groups I were administered with just distil water (2 ml/kg). Rats in groups II were administered with lead acetate (30 mg/kg) while rats in groups III–V were administered Adansonia digitatata (L) fruit extract (250 mg/kg and 500 mg/kg) and Succimer (5 mg/kg) respectively, then additionally challenged with lead acetate (30 mg/kg) immediately after. At the end of the administration, the blood serum from the experimental rats were used for biochemical analysis. Then, the the organs such as the liver and kidney collected for histological study. Results Rats administered with Lead acetate showed an increase in AST, ALP and ALT as well as increase in urea and creatinine level (p Adansonia digitatata (L) fruit prevented the effect (upsurge of serum, Urea, Creatinine, AST, ALP and ALT) of lead acetate. Rats administer with only Lead acetate revealed marked liver steatosis and the degeneration of the kidney glomerulus. The Adansonia digitatata (L) fruit extract and Succimer prevented the histological liver steatosis, as well as the degeneration of the glomerulus of the kidney cytoarchitecture. Conclusion The findings in this study suggest that Adansonia digitata fruits extract has a protective potentials against lead acetate induced liver and kidney toxicity by preventing the upsurge of liver function enzymes and kidney function parameters. Hence, Adansonia digitata fruits can serve as a natural plant agent that can prevent hepato-renal toxicity. Therefore, Adansonia digitata holds future prospects in preclinical framework to ameliorate organs toxicity for oral therapeutic applications.

This work investigates the synthesis of Mg-Fe layered double hydroxides intercalated by sulphate (Mg-Fe-SO4) or dodecylsulfate (Mg-Fe-SDS) and their capacity to adsorb methyl orange (MO), as a mode...

Myoglobin (MG) is a biomarker for heart muscle injury, making it a potential target protein for early detection of myocardial infarction. Elevated myoglobin levels alone have low specificity for acute myocardial infarction (AMI) but in combination with cardiac troponin T have been considered highly efficient diagnostic biomarkers. Myoglobin is a monomeric heme protein with a molecular weight of 17 kDa that is found in skeletal and cardiac tissue as an intracellular storage unit of oxygen. MG consists of eight α-helices connected by loops and a heme group responsible for oxygen-binding. Monoclonal antibodies are widely used analytical tools in biomedical research and have been employed for immunoanalytical detection of MG. However, the epitope(s) recognized by MG antibodies have been hitherto unknown. Precise molecular identification of the epitope(s) recognized by antibodies is of key importance for the development of MG as a diagnostic biomarker. The epitope of a monoclonal MG antibody was identified by proteolytic epitope extraction mass spectrometry in combination with surface plasmon resonance (SPR) biosensor analysis. The MG antibody was immobilized both on an affinity microcolumn and a gold SPR chip. The SPR kinetic analysis provided an affinity-binding constant KD of 270 nM for MG. Binding of a tryptic peptide mixture followed by elution of the epitope from the SPR-MS affinity interface by mild acidification provided a single-epitope peptide located at the C-terminus [146-153] [YKELGFQG] of MG. The specificity and affinity of the epitope were ascertained by synthesis and affinity-mass spectrometric characterization of the epitope peptide.

Analytical methods for molecular characterization of diagnostic or therapeutic targets have recently gained high interest. This review summarizes the combination of mass spectrometry and surface plasmon resonance (SPR) biosensor analysis for identification and affinity determination of protein interactions with antibodies and DNA-aptamers. The binding constant (KD) of a protein–antibody complex is first determined by immobilizing an antibody or DNA-aptamer on an SPR chip. A proteolytic peptide mixture is then applied to the chip, and following removal of unbound material by washing, the epitope(s) peptide(s) are eluted and identified by MALDI-MS. The SPR-MS combination was applied to a wide range of affinity pairs. Distinct epitope peptides were identified for the cardiac biomarker myoglobin (MG) both from monoclonal and polyclonal antibodies, and binding constants determined for equine and human MG provided molecular assessment of cross immunoreactivities. Mass spectrometric epitope identifications were obtained for linear, as well as for assembled (“conformational”) antibody epitopes, e.g., for the polypeptide chemokine Interleukin-8. Immobilization using protein G substantially improved surface fixation and antibody stabilities for epitope identification and affinity determination. Moreover, epitopes were successfully determined for polyclonal antibodies from biological material, such as from patient antisera upon enzyme replacement therapy of lysosomal diseases. The SPR-MS combination was also successfully applied to identify linear and assembled epitopes for DNA–aptamer interaction complexes of the tumor diagnostic protein C-Met. In summary, the SPR-MS combination has been established as a powerful molecular tool for identification of protein interaction epitopes.

Paracetamol is a non-steroidal, anti-inflammatory drug widely used in pharmaceutical applications for its sturdy, antipyretic and analgesic action. However, an overdose of paracetamol can cause fulminant hepatic necrosis and other toxic effects. Thus, the development of advantageous analytical tools to detect and determine paracetamol is required. Due to simplicity, higher sensitivity and selectivity as well as costefficiency, electrochemical sensors were fully investigated in last decades. This review describes the advancements made in the development of electrochemical sensors for the paracetamol detection and quantification in pharmaceutical and biological samples. The progress made in electrochemical sensors for the selective detection of paracetamol in the last 10 years was examined, with a special focus on highly innovative features introduced by nanotechnology. As the literature is rather extensive, we tried to simplify this work by summarizing and grouping electrochemical sensors according to the by which manner their substrates were chemically modified and the analytical performances obtained., Graphical abstract Image 1, Highlights • An overview of the electrochemical sensors developed for the sensing of paracetamol in the last 10 years. • Carbon paste, glassy carbon and screen printed are the most investigated carbon-based electrodes. • Multiwalled carbon nanotubes-based composites are the most efficient modifiers for paracetamol detection. • Metal organic frameworks allowed the detection of paracetamol at picomolar levels. • Differential pulse voltammetry was the most useful to discriminate multiple compounds and improve sensitivity.

Background: Klebsiella pneumoniae is a bacterial pathogen commonly associated with severe nosocomial and community acquired infections especially through the acquisition of extended spectrum β-lactamases (ESβL) and biofilm formation capacity. The objectives of this study are to determine the prevalence of K. pneumoniae ESβL (KP-ESβL)-producing isolates in the Regional Military University Hospital of Oran (HMRUO) Algeria,characterize their antibiotic resistance profile, genetically detect blaTEM and blaCTX-M genes, and evaluate their biofilm formation capacity.Methodology: Different clinical specimens including blood, cerebrospinal fluids, urine and catheter, pus, perirectal abscess, and surgical wounds were collected from patients with suspected clinical infections in different units and departments of the hospital. The specimens were cultured on Blood, MacConkey and CLED agar (for urine only) plates and incubated aerobically for 24 hours at 37°C for preliminary identification of bacteria using conventional colony morphology, Gram stain reaction, and disk diffusion test for antibiotic susceptibility testing (AST). Confirmation of isolates, antibiogram, minimum inhibitory concentration (MIC) and detection of resistance phenotypes, were carried out by the automated Vitek 2 (BioMérieux) identification and susceptibility method. ESβL production was confirmed by the synergy and combination disk tests. ESβL genes were detected by conventional simplex PCR and biofilm formation was detected by the tissue culture plate (TCP) method.Results: A total of 630 patients’ clinical samples (one sample per patient) were processed. Klebsiella pneumoniae was isolated in 40 (6.3%) samples, and 15 of these (37.5%) produced ESβL. In the disk diffusion AST assay, all 40 K. pneumoniae isolates were resistant to ampicillin and ticarcillin while all 40 isolates were sensitive to cefoxitin, imipenem and ertapenem. KP-ESβL producing isolates were more frequently recovered from intensive care unit (33.3%) and from urine (46.7%) samples. Group 1 blaCTX-M genes were detected in 13 of the 15 (86.7%) KP-ESβL isolates, and 46.7% of these isolates were moderate biofilm producers.Conclusion: There is need for health departments to put in place preventative measures through regular surveillance of these resistant pathogens and initiating appropriate infection prevention and control strategies to limit their spread in Algerian hospitals and worldwide. Keywords: Klebsiella pneumoniae, ESβL, biofilm, PCR, antibacterial resistance French title: Klebsiella pneumoniae productrice de-lactamase spectre tendu dans l'hôpital universitaire militaire régional d'Oran, Algérie: résistance aux antibiotiques, formation de biofilm et détection desgènes blaCTX-M et blaTEM Contexte: Klebsiella pneumoniae est un pathogène bactérien communément associé aux infectionsnosocomiales et communautaires sévères, en particulier par l'acquisition de β-lactamases à spectre étendu(ESβL) et la capacité de formation de biofilm. Les objectifs de cette étude sont de déterminer la prévalence desisolats de K. pneumoniae producteurs de βLSE (KP-βLSE) au CHU d'Oran (HMRUO) Algérie, caractériser leurprofil de résistance aux antibiotiques, détecter génétiquement les gènes blaTEM et blaCTX-M, et évaluer leurcapacité de formation de biofilm.Méthodologie: Différents échantillons cliniques, y compris du sang, des liquides céphalo-rachidiens, de l'urinemictionnelle et du cathéter, du pus, des abcès périrectal et des plaies chirurgicales ont été prélevés despatients suspectés d'infections cliniques dans différentes unités et départements de l'hôpital. Les échantillonsont été cultivés sur des milieu de culture: deglose au sang, MacConkey et CLED (pour l'urine uniquement) etincubés en aérobie pendant 24heures à 37°C pour l'identification préliminaire des bactéries en utilisant lamorphologie conventionnelle des colonies, la coloration de Gram et le test de diffusion sur disque pour les testsde sensibilité aux antibiotiques (AST). La confirmation des isolats, l'antibiogramme, la concentration minimaleinhibitrice (CMI) et la détection des phénotypes de résistance ont été réalisés par la méthode automatiséed'identification et de sensibilité sur Vitek 2 (BioMérieux). La production de βLSE a été confirmée par les tests desynergie et de double disques. Les gènes de βLSE ont été détectés par PCR simplex conventionnelle et laformation de biofilm a été détectée par la méthode de la plaque de culture tissulaire (TCP).Résultats: Un total de 630 échantillons cliniques de patients (un échantillon par patient) ont été traités.Klebsiella pneumoniae a été isolé dans 40 échantillons (6,3%) et 15 d'entre eux (37,5%) ont produit des βLSE.Dans le test AST à diffusion sur disque, tous les 40 isolats de K. pneumoniae étaient résistants à l'ampicilline età la ticarcilline, tandis que les 40 isolats étaient sensibles à la céfoxitine, à l'imipénème et à l'ertapénème. Lesisolats producteurs de KP-βLSE ont été plus fréquemment récupérés dans les unités de soins intensifs (33,3%)et dans les échantillons d'urine (46,7%). Les gènes blaCTX-M du groupe 1 ont été détectés dans 13 des 15 isolatsde KP-βLSE (86,7%), et 46,7% de ces isolats étaient des producteurs de biofilm modérés.Conclusion: Il est nécessaire que les services de santé mettent en place des mesures préventives grâce à unesurveillance régulière de ces pathogènes résistants et à la mise en place de stratégies appropriées deprévention et de contrôle des infections pour limiter leur propagation dans les hôpitaux algériens et dans lemonde. Mots clés: Klebsiella pneumoniae, βLSE, biofilm, PCR, résistance antibactérienne

Emerging contaminants have recently aroused attention because of their harmful impact on ecosystem and human health. Among those contaminants, standout gallic acid which is known for its high toxic...

The aim of this study is to evaluate the Mg-Al layered double hydroxides (LDHs) containing dodecyl sulfate and carbonate ions in the removal of methyl orange (MO) from aqueous solution. The prepared materials (Mg-Al-CO3 and Mg-Al-Ds) were characterized by XRD, TEM and FT-IR methods. XRD patterns of the two materials show the interlayer type structure with (00 l) reflections. TEM analysis showed that the LDH samples have nanoscale structures. FTIR spectroscopy confirmed the presence of the desired anions in the interlayer space. The results of the adsorption experiences for MO were performed as a function of solution pH and contact time. The adsorption ability of MO onto Mg-Al-CO3 was practically influenced by pH solution. However, the adsorption capacity of MO by Mg-Al-Ds appears stable at the different values of solution pH. The maximum adsorption capacities were 185.06 and 97.5 mg/g for Mg-Al-Ds MB and Mg-Al-CO3, respectively. The adsorption tests recommend the use of organic LDHs as potential adsorbents for azo dye treatment in a wide range of pH.

This work involved the removal of textile dyes by synthesized Ni-Fe-SDS and Ni-Fe-SO4 layered double hydroxides (LDH). The adsorbent was synthesized using co-precipitation method at room temperature. Samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) and inductively coupled plasma (ICP). The obtained materials were used for the removal of methyl orange (MO) as a model anionic dye. Adsorption experiments were carried out under different solution pH and contact time. XRD analyses indicate low degree of crystallinity when using SDS as an intercalating anion in the LDH structure. Experimental results indicate rapid adsorption process with maximum adsorption capacity occurred in acidic medium. The maximum adsorption capacities were 105.36 and 82.45 mg/g, respectively for Ni-Fe-SDS and Ni-Fe-SO4 samples.

Apium graveolens var. dulce commonly known as celery, belongs to the Apiaceae family. It is used especially as a vegetable and medicinal plant. In Senegal, A. graveolens is used as a food condiment. The aim of this work is to study the chemical composition of A. graveolens stems (S), leaves (L) essential oils and anti-inflammatory activity. GC/FID and GC/MS analyzes carried out on essential oils obtained by steam distillation showed that oils from both stems and leaves were characterized by the same major constituents α-pinene, the prominent compound of oils represented 69.3 and 68.4% for stems (S) and leaves (L), respectively. It is followed by limonene (9.5 and 9.8%), α-phellandrene (5.5 and 5.9%) and β-pinene (4.8 and 4.3%). These compounds represented 89.1% (S) and 88.4% (L) of the total essential oils content. Anti-inflammatory activity was measured by the inhibition of 5-lipoxygenase (5-LOX) by A. graveolens essential oil anti-inflammatory assays revealed an IC50 of 29.5±2.0 µg/mL for A. graveolens oils and 23.7±0.5 µg/mL for quercetine used as a reference. This study showed that essential oils of A. graveolens was an important source of α-pinene who is probably responsible of its anti-inflammatory properties.

In order to mitigate debris in the low Earth orbit and to avoid dramatic collisions on Earth after atmospheric reentry at its end of life, the spacecraft mission has to take into account the influence of reentry on the spacecraft survivability. In this way, oxidation in air plasma conditions was studied on metallic alloys such as TA6V to obtain oxidation kinetic laws at high temperature and for short time duration (few minutes). Experimental results obtained for the oxidation of TA6V at high temperature and low pressure in air plasma conditions together with microstructural characterization using SEM and XRD are presented. For a constant holding time of oxidation of 300 s for two total air pressures (300 and 2000 Pa) in the temperature range 1300–1900 K, the mass variation versus reciprocal temperature follows an Arrhenius law that gives a same activation energy of around 62–64 kJ/mol showing the low influence of pressure. Then kinetics laws were obtained for a constant temperature of 1830–1840 K for 3 pressures (300, 2000 and 5000 Pa) in the short time interval 50–470 s. The oxidation of the TA6V alloy by atomic oxygen leads to the spallation of the oxide layers even for short duration, and thus, the space debris during its atmospheric reentry will lose very few mass and the debris will reach the Earth only partially destroyed. The mass loss was calculated, and finally, it was shown that it represents only 0.5‰ of the initial mass of the TA6V alloy.

This study is focused on the preparation of activated carbon based on carob shells waste by chemical activation with ZnCl2. The Box-Behnken experimental design with 17 experiences was used to optim...

The production of chili pepper (Capsicum annuum L.) is hindered by several biotic factors even though striding progresses were made in genetic improvement in the last two decades. Among the advancements were the fast-track genetic improvement of disease-resistant varieties by the use of marker-assisted selection (MAS) and the conventional breeding-based introgression of major resistance genes. Marker development, marker-based identification and fine mapping have revealed a large number of resistance genes, from which cloning of some candidate genes demonstrated the applicability and versatility of map-based cloning for disease resistance. In some of the recent fine mapping of disease resistance QTLs, closely linked DNA markers were identified, which in turn resulted in the rapid introgression of target gene(s) into breeding lines. Also, progresses were made on the characterization and map-based cloning of resistance genes conferring broad-spectrum resistance. As the number of identified and characterized resistance genes and the DNA markers linked to resistance genes are steadily generated, the development of multiple/durable resistance to major chili pepper diseases is accelerated by MAS. In the present review, the development of molecular markers, marker-based mapping of genes conferring resistance to ten major chili pepper diseases were discussed, focusing on the recent advancements in major and QTL-spanning resistance gene mapping. The review provides up-to-date insights into the development of DNA markers linked to disease resistance genes and the cloning of resistance genes, which are all so crucial in pepper breeding for disease resistance.

Chickpea (Cicer arietinum L.) is an important legume plant which is being affected by drought stress. Due to drought, chickpea production has been low in Ethiopia and other chickpea producing countries. Hence, the aim of this study was to reduce the impact of drought on chickpea plant by taking advantage of consortium effect of Mesorhizobium ciceri CP41 and Pseudomonas fluorescens Biotype G. Two chickpea varieties, Habru (drought tolerant) and Arerti (drought susceptible) were used to study the effect of the two bacterial consortia in moderating the effects of drought stress on some morphological, physiological and biochemical traits. The results showed that co-inoculation had significantly improved fresh and dry weight of leaves, root and shoot (p

The modern consumer values those components that can promote their well-being and help them reduce the risk of diseases the use of steviolglucosides as a sweetener in the formulation of foods is promising. The study evaluated the tangential microfiltration for clarification and conservation of blackberry juice sweetened with dried leaves of stevia. Two ceramic membranes were evaluated. The tests were performed at 35°C in concentration mode at a constant transmembrane pressure and tangential velocity. The formulation of the juice was defined through sensory evaluation tests. Volume, flow permeate, temperature, and pressure input and output were registered. The results of the variables analyzed in the process, as well as the physicochemical characterization of clarified juice, helped define the operating conditions for draw two formulations of microfiltrated juice, sweetened with stevia or sucrose, and thus evaluate the effectiveness of microfiltration as a conservation treatment. Aciduric microorganisms were quantified; molds and yeasts were carried out in the generated pasteurized samples stored at five different temperatures (5, 20, 30, 37, and 45°C). The recovery permeate juice obtained was 84.62%. The permeate Flow (Jp), exhibited higher values at 40L/hm2. Also, the concentration of stevioside and rebaudioside A in the retentate increased with advancing ultrafiltration. A significant variation in color, turbidity, and soluble solids, was observed, unlike the pH. Also, its chemical and microbiological stability is confirmed that allows you to preserve quality during 27 days of storage. RESUMEN Dada la importancia que el consumidor moderno le otorga a aquellos componentes que puedan promover su bienestar y ayudarle a reducir el riesgo de enfermedades, el uso de los esteviolglucósidos como edulcorante en la formulación de alimentos resulta prometedor. El presente estudio evaluó la microfiltración tangencial como tratamiento de clarificación y conservación de un jugo de mora endulzado con hojas deshidratadas de estevia. Se evaluaron dos membranas cerámicas. Los ensayos fueron efectuados a 35°C en modo concentración, a una presión transmembranaria y velocidad tangencial constante. La formulación del jugo fue definida a través de pruebas de evaluación sensorial. Se registró el volumen, flujo del permeado, la temperatura y la presión de entrada y salida. Los resultados de las variables analizadas y la caracterización fisicoquímica del jugo microfiltrado, permitieron definir las condiciones de operación para elaborar dos formulaciones, uno endulzado con estevia y otro con sacarosa y así evaluar la efectividad de la microfiltración. También se efectuaron recuentos de acidúricos, mohos y levaduras, en las muestras pastaurizadas almacenadas a cinco diferentes temperaturas (5, 20, 30, 37 y 45ºC). El estudio permitió obtener un 84,62% de recuperación del jugo permeado. El flujo de permeado (Jp), exhibió valores superiores a 40L/hm2. La concentración de esteviósido y rebaudiósido A en el retenido aumentó al avanzar la ultrafiltración. Se apreció, una variación de color, turbidez y sólidos solubles, a diferencia del pH. Asimismo se corroboró su estabilidad química y microbiológica al conservar su calidad durante 27 días de almacenamiento.

This study focused on the preparation of activated carbons from Thapsia transtagana stems by boric acid activation and their evaluation for dyes removal. The central composite design and response surface methodology were used to optimize the preparation conditions. The effect of activation temperature, impregnation ratio and activation time on iodine number (IN), methylene blue index (MB index) and removal efficiencies of methyl violet (MV), methyl orange (MO) and indigo carmine (IC) were fully evaluated. The activated carbon samples prepared in optimal conditions were characterized by FTIR, XRD, SEM-EDX, Boehm's titration, and point of zero charge (pHPZC). The equilibrium data for dyes sorption onto optimum activated carbons were best fitted with Langmuir isotherm. Keywords: Thapsia transtagana stems, Dyes removal, Chemical activation, Central composite design

Nano zerovalent iron (nZVI), produced from green tea extracts, was incorporated in a cation exchange resin (R-nFe) to investigate its performance regarding the removal of four non-steroidal anti-inflammatory drugs (NSAIDs): ibuprofen (IBU), naproxen (NPX), ketoprofen (KTP) and diclofenac (DCF). The effect of contact time, NaCl pretreatment, pH, R-nFe dose, the role of the supporting material, the initial concentration of pollutants, and the combined effect of nZVI with oxidative reagents was assessed through a series of batch experiments. According to the results, the best removal efficiencies obtained for DCF and KTP were 86% and 73%, respectively, at 48 h of contact time with NaCl pretreated R-nFe at a dose of 15 g L−1 and a pH of 4. The maximum removal efficiency for NPX was 90% for a contact time of 60 min with PS 1 mM and a pH of 3, which was quite similar to the experiment with a greater contact time of 48 h without PS addition. The maximum IBU removal was 70%, this was reached at pH 3, with a contact time of 30 min and R-nFe 15 g L−1. To the authors’ best knowledge, this is the first study investigating the utilization of nZVI, produced from leaf extracts and incorporated into a cationic exchange resin, to remove NSAIDs from water.

d-tagatose is a rare monosaccharide, naturally present at low concentrations in some fruits and dairy products.d-tagatose is "generally recognized as safe" and is used as a low-calorie sweetener in the food industry.It is able to inhibit the growth of numerous microorganisms, such as phytopathogenic oomycetes responsible for important crop diseases. Thanks to the negligible effects on human health and the environment,d-tagatose has been proposed as a sustainable product for crop protection. This review describes the current knowledge on modes of action ofd-tagatose against phytopathogenic oomycetes and its potential uses in agriculture.d-tagatose can negatively affect the growth of phytopathogenic oomycetes by inhibiting key enzymes of sugar metabolism, such as β-glucosidase inPhytophthora infestans, and fructokinase and phosphomannose isomerase inHyaloperonospora arabidopsidis. Moreover,d-tagatose affects sugar content, causes severe mitochondrial alterations, and inhibits respiration processes with the accumulation of reactive oxygen species inP.infestans, but not inP.cinnamomi. Differential effects ofd-tagatose are associated with a global gene downregulation inP.infestansand with an efficient transcriptional reprogramming of multiple metabolic processes inP.cinnamomi.d-tagatose displays possible species-specific effects inPhytophthoraspp. and nutritional properties on some plant-associated microorganisms. However, inhibitory effects are reversible andP.infestansgrowth can be restored in the absence ofd-tagatose. Further functional studies are discussed in this review, in order to promote the use ofd-tagatose for sustainable crop protection.

Heavy metals represent one of the most important kinds of pollutants, causing serious threats to the ecological balance. Thus, their removal from aqueous solution is a major environmental concern worldwide. The process of adsorption—being very simple, economical, and effective—is widely applied for the decontamination of wastewaters from heavy metals. In this process, the adsorbent is the key factor affecting the performance; for this reason, significant efforts have been made to develop highly efficient and selective adsorbents with outstanding properties. This paper presents a detailed overview of the research on different methods of synthesis of nanocomposite materials based on the polymer polyaniline combined with nanomaterials, along with the influence of the synthesis method on their size, morphology, and properties. In addition, the study evaluates the adsorption efficiency of various developed nanocomposites for the adsorption of heavy metals from aqueous solution. From an economical and environmental point of view, the regeneration studies of the nanocomposites are also reported.

Olive mill wastewater (OMW) poses severe problems for aquatic and environmental systems, especially in the Mediterranean region, therefore, its treatment is of great interest. This study aimed the removal of phenolic compounds from OMW by sugarcane bagasse (SCB) as a low-cost adsorbent. Different parameters influencing the adsorption such as adsorbent dose, solution of pH, contact time and temperature were optimized. I was found that SCB can be used as an effective and low-cost adsorbent to remove phenolic compounds from OMW. Application of experimental design approach showed an optimum of 60% removal after 60 min at 60 °C and pH of 12. Langmuir and Freundlich isotherm models were used to describe the equilibrium date, while kinetics data were fitted to pseudo-first-order and pseudo-second-order kinetic models. The obtained results showed that the equilibrium data were best fitted to Freundlich model. The Langmuir model also gives good correlation and shows an adsorption capacity of 57.7 mg/g. kinetics data followed pseudo-second-order model instead of pseudo-second-order model. The thermodynamic parameters including ∆G°, ∆H° and ∆S° were also investigated and suggested an exothermic process. In addition, high energy value of SCB both before (13.15 MJ/kg) and after adsorption (15.58 MJ/kg) indicates its potential for use as an alternative energy source.

Diclofenac is a non-steroidal anti-inflammatory drug of wide use around the world for the treatment of several diseases such as ankylosing spondylitis, acute muscle pain conditions, and osteoarthritis. Although in proper doses it does not display any side effects, an overdose of diclofenac can cause adverse effects in the human body. Moreover, the presence of diclofenac in ecosystems directly affects the health of living organisms, even if it is present at trace. Therefore, the development of analytical tools for diclofenac monitoring was needed. In this context, electrochemical sensing and biosensing methods have been commonly reported. In this review, a critical evaluation of the methods employed for diclofenac analysis is presented according to the following classifications: potentiometric sensors, sensing at non-modified solid electrodes, chemically modified electrodes and biosensors. Recent developments related to the use of electrochemical detection of diclofenac in pharmaceutical formulations, biological fluids and environmental samples were reported and discussed.

Tagatose is a rare sugar with no negative impacts on human health and selective inhibitory effects on plant-associated microorganisms. Tagatose inhibited mycelial growth and negatively affected mitochondrial processes in Phytophthora infestans, but not in Phytophthora cinnamomi. The aim of this study was to elucidate metabolic changes and transcriptional reprogramming activated by P. infestans and P. cinnamomi in response to tagatose, in order to clarify the differential inhibitory mechanisms of tagatose and the species-specific reactions to this rare sugar. Phytophthora infestans and P. cinnamomi activated distinct metabolic and transcriptional changes in response to the rare sugar. Tagatose negatively affected mycelial growth, sugar content and amino acid content in P. infestans with a severe transcriptional reprogramming that included the downregulation of genes involved in transport, sugar metabolism, signal transduction, and growth-related process. Conversely, tagatose incubation upregulated genes related to transport, energy metabolism, sugar metabolism and oxidative stress in P. cinnamomi with no negative effects on mycelial growth, sugar content and amino acid content. Differential inhibitory effects of tagatose on Phytophthora spp. were associated with an attempted reaction of P. infestans, which was not sufficient to attenuate the negative impacts of the rare sugar and with an efficient response of P. cinnamomi with the reprogramming of multiple metabolic processes, such as genes related to glucose transport, pentose metabolism, tricarboxylic acid cycle, reactive oxygen species detoxification, mitochondrial and alternative respiration processes. Knowledge on the differential response of Phytophthora spp. to tagatose represent a step forward in the understanding functional roles of rare sugars.

Roots are prominent plant-microbe interaction sites and of great biological relevance for many studies. The root response is of interest when searching for potential systemic resistance inducers. Screening of elicitors often focuses on the oxidative burst, the rapid and transient production of Reactive Oxygen Species (ROS). However, to our knowledge, no high-throughput, sensitive methods have been developed for the quantification of ROS released by roots. Here, we report on the development of an L-012-based chemiluminescence bioassay to quantitatively determine the oxidative burst following elicitation events in roots. Rice and grapevine were used as monocot and dicot models. We demonstrate that chitosan, a recognized elicitor in rice cells, was able to elicit ROS production in rice roots. Chitosan also triggered a strong oxidative burst in grapevine cell suspension cultures, while grapevine roots were not responsive. Although this method is broadly applicable, the L-012 probe requires careful consideration of solvents and plant species. Insufficient extracellular ROS, quenching, and the interference of solvents with the probe can undermine the assay sensitivity.

In this work, a promising photocatalyst was prepared and investigated for the photocatalytic degradation of caffeine as a model pharmaceutical pollutant. Mg-doped ZnO-Al2O3 heterostructure with different content of Mg (1, 3 and 5 wt%) was prepared from Zn-Al-CO3 layered double hydroxides precursors using ceramic process. The synthesized catalysts were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) coupled with energy dispersive X-ray analysis (EDX) and UV–vis diffuse reflectance spectroscopy (UV–vis DRS). The photocatalytic activity of the catalysts was evaluated for the degradation of caffeine in aqueous solutions under UV irradiation. Detailed experiments based on the effect of doping amount, irradiation time, photocatalyst dose, initial solution pH, caffeine concentration and reuse were performed and discussed in this study. The 1%Mg-ZnO-Al2O3 sample showed the highest photocatalytic activity with a degradation efficiency of 98.9% after 70 min of irradiation. This catalyst showed significantly higher degradation efficiency compared to undoped, pure ZnO and standard Degussa P-25 titanium dioxide. The photocatalyst showed good stability after three regeneration cycles.

Damping-off caused by Pythium aphanidermatum, as one of the most infamous plant diseases, is considered as a significant disease that causes severe damages in greenhouse and field crops in a vast range of hosts especially vegetables. The application of chemical fungicides as a common method to control this disease poses negative side effects on humans and the environmental components. Actinobacteria, especially members of the genus Streptomyces, are fascinating biocontrol agents and plant growth-promoting rhizobacteria, which exhibit safer alternative managements to control this disease. The present study aims to explore for bioactives soil Streptomyces isolates that are able to control P. aphanidermatum, which is the causal agent of damping-off in tomato. Out of a total of 116 actinobacteria isolates collected from the soil, 53 have showed an antagonistic activity against P. aphanidermatum, as deduced through in vitro dual cultures. Based on in vitro Petri plate seedling-bioassays (IPSB), from the 53 tested isolates in dual cultures, two isolates coded as H2 and H3, considered as the most bioactive agents, were selected to assess their biocontrol performances against P. aphanidermatum in the Sandwich bed-mix technique in greenhouse experiments. In vivo greenhouse statistical studies were performed to compare seven treatments using completely randomized design experiments. Metalaxyl fungicide was applied as the chemical-control treatment. To evaluate biocontrol efficiencies of the two Streptomyces symbionts, disease incidence recorded throughout the course of experiment and criteria of number of leaves, length of the plants, plant fresh and dry weights, were measured at the end of experiment and analyzed statistically. The resulted disease incidences for all treatments indicated that the two Streptomyces strains had PGPR activity, and they were effective in decreasing disease incidence and improving plant performances regarding number of leaves, height, and plant fresh and dry weights. Based on the phylogenetic analysis of the partial sequences of the 16S rRNA gene, the strain H2 revealed a close relation to six Streptomyces species, namely S. badius, S. caviscabies, S. globisporus, S. parvus, S. sindenensis, and S. griseoplanus, with 99.9% similarity. The strain H3 also indicated a close relation of the same similarity to two species, namely S. flavogriseus and S. pratensis. In overall, collected data dictated that the two bioactive root symbiont Streptomyces strains effectively controlled the damping-off disease caused by P. aphanidermatum.

International audience; A series of magnesium phosphate samples modified by incorporation of aluminium, denoted MgAlP-x (where x indicates the Al molar ratio%; x = 0; 10; 20; 40%), have been prepared by coprecipitation method followed by characterization. Their structures have been investigated by using powder X-ray diffraction, the surface area by physisorption of nitrogen (BET), Fourier transform infrared (FTIR) were used to characterize the functional groups of solids and MAS–NMR spectroscopy. X-ray diffractograms for synthesized materials suggest the formation of mixed solids, such as Mg3(PO4)2, AlPO4 and Al2O3. Incorporation of aluminium into magnesium orthophosphate increased the temperature of crystallization, so that MgAlP-x systems retained amorphous up to 973 K. The specific surface area increases with aluminium content. 31P MAS–NMR spectra of calcined MgP shows a single peak at δ = +0.4 ppm and two overlapped signals for calcined MgAlP-x (x = 20 and 40%). But the dry solids present more than a single peak. The varying values of chemical shifts are due to the existence of different types of 31P structural configurations and oxygen environment. 27Al MAS-NMR spectra of sample exhibit two peaks, which were characteristic of the octahedral and tetrahedral environments of Al3+ ions. It was observed that the incorporation of Al in MgP material decreases the patent blue V (PB) photodegradation. The highest dye degradation was obtained over the MgP catalyst (without Al). No correlation between the adsorption before UV irradiation and the rate of photodegradation.

The main objective of this study was to evaluate the ability of both antagonistic bacteria Bacillus amyloliquefaciens (SF14) and Alcaligenes faecalis (ACBC1) used in combination with salicylic acid (SA) to effectively control brown rot disease caused by Monilinia fructigena. Four concentrations of salicylic acid (0.5%, 2%, 3.5%, and 5%) were tested under in vitro and in vivo conditions. Furthermore, the impact of biological treatments on nectarine fruit parameters&rsquo, quality, in particular, weight loss, titratable acidity, and soluble solids content, was evaluated. Regardless of the bacterium, the results indicated that all combined treatments displayed a strong inhibitory effect on the mycelial growth of M. fructigena and disease severity. Interestingly, all SA concentrations significantly improved the biocontrol activity of each antagonist. The mycelial growth inhibition rate ranged from 9.79% to 88.02% with the highest reduction rate recorded for bacterial antagonists in combination with SA at both concentrations of 0.5% and 3.5%. The in vivo results confirmed the in vitro results with a disease severity varying from 0.00% to 51.91%. A significant biocontrol improvement was obtained with both antagonistic bacteria when used in combination with SA at concentrations of 0.5% and 2%. The lowest disease severity observed with ACBC1 compared with SF14 is likely due to a rapid adaptation and increase of antagonistic bacteria population in wounded sites. The impact of all biological treatments revealed moderate significant changes in the fruit quality parameters with weight loss for several treatments. These results suggest that the improved disease control of both antagonistic bacteria was more likely directly linked to both the inhibitory effects of SA on pathogen growth and induced fruit resistance.

In this study, density functional theory (DFT) calculations combined with molecular dynamics (MD) simulation have been used to understand the adsorption mechanism of sulfur dioxide (SO2) and carbon dioxide (CO2) on the graphite surface in aqueous medium, in view of analytical and environmental application. The global reactivity descriptors, such as the frontier molecular orbital energies (EHOMO and ELUMO), gap energy (ΔEgap), absolute hardness (η) and softens (σ), fraction of electrons transferred (ΔN) and electronegativity (χ) were evaluated. The dynamic descriptors calculated by the MD simulation such as the adsorption energy (Eads), total energy (Etot), deformation energy (Edef), rigid adsorption energy (RAE) and dEads/dNi were also calculated and discussed. The obtained results indicated strong electron acceptor ability and high adsorption energy, which can suggest good adsorption ability. The interaction energies (ΔEinteraction) were negative for both gases indicating strong attractive force between the molecules and the graphite surface. The highest values of the binding energy (ΔEbinding) indicate that the adsorption of each molecule is strong and stable, which is in agreement with the interaction energies. The values of EHOMO and Eads were negative, indicating that the complete chemical processes occur spontaneously. Furthermore, MD simulation was applied to investigate the most stable configuration of the molecules on the graphite (111) surface. The larger Eads and the smaller bond distances indicate that graphite exhibited higher sensitivity to interact with SO2 and CO2 molecules in an aqueous medium.

In this study, cobalt sulfide-reduced graphene oxide (CoS-rGO) nanocomposite was prepared by a solvothermal route and its structure, morphology and composition were assessed using various techniques, including transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA). The catalytic performance of CoS-rGO was evaluated for activation of peroxymonosulfate (PMS) for the elimination of rhodamine B (RhB) and pentachlorophenol (PCP) in water. The effects of various operating parameters on the degradation efficiency were systematically studied. Under optimized operating conditions, the CoS-rGO/PMS system achieved fast (less than 10 min) elimination of RhB and PCP at room temperature, as evidenced by high-performance liquid chromatographic (HPLC) analysis. Electron Paramagnetic Resonance (EPR) studies along with scavenging experiments revealed that sulfate radicals ( S O 4 • − ) were the primary players in the catalytic process. Interestingly, the CoS-rGO catalyst was stable after 8 cycles without obvious activity loss. The results reported in the present study hold promise for potential application of CoS-rGO for PMS activation for the elimination of various organic pollutants.

Actin γ 2, smooth muscle (ACTG2) R257C mutation is the most common genetic cause of visceral myopathy. Individuals with ACTG2 mutations endure prolonged hospitalizations and surgical interventions, become dependent on intravenous nutrition and bladder catheterization, and often die in childhood. Currently, we understand little about how ACTG2 mutations cause disease, and there are no mechanism-based treatments. Our goal was to characterize the effects of ACTG2R257C on actin organization and function in visceral smooth muscle cells. We overexpressed ACTG2WT or ACTG2R257C in primary human intestinal smooth muscle cells (HISMCs) and performed detailed quantitative analyses to examine effects of ACTG2R257C on (a) actin filament formation and subcellular localization, (b) actin-dependent HISMC functions, and (c) smooth muscle contractile gene expression. ACTG2R257C resulted in 41% fewer, 13% thinner, 33% shorter, and 40% less branched ACTG2 filament bundles compared with ACTG2WT. Curiously, total F-actin probed by phalloidin and a pan-actin antibody was unchanged between ACTG2WT- and ACTG2R257C-expressing HISMCs, as was ultrastructural F-actin organization. ACTG2R257C-expressing HISMCs contracted collagen gels similar to ACTG2WT-expressing HISMCs but spread 21% more and were 11% more migratory. In conclusion, ACTG2R257C profoundly affects ACTG2 filament bundle structure, without altering global actin cytoskeleton in HISMCs., A mutation associated with visceral myopathy profoundly disrupts actin gamma 2, smooth muscle (ACTG2) filament bundles without changing the global actin cytoskeleton in visceral smooth muscle cells.

Crown gall disease of grapevine, caused by Agrobacterium tumefaciens, often results in severe economic loss to grape production worldwide. This study demonstrated the ability of the endophytic bacteria Pseudomonas sp. Sn48 and Pantoea sp. Sa14 isolated from domesticated and wild grapevines to induce resistance in both above‐ and belowground tissues of grapevines infected with A. tumefaciens. Our results provide evidence that both strains can colonize roots and/or shoots. We showed that the strains Pseudomonas sp. Sn48 and Pantoea sp. Sa14 are capable of inducing stilbenic phytoalexin production in grapevine tissues and to further prime plantlets for enhanced phytoalexin production after A. tumefaciens inoculation. We also showed that in the majority of treatments, polyamine accumulation remained unchanged or slightly increased in plantlets treated with Pseudomonas sp. Sn48 and Pantoea sp. Sa14 compared with the control. Our findings indicated that the levels of polyamines remain unchanged or significantly decrease in plantlets treated with endophytic bacteria after A. tumefaciens challenge compared to the control and plantlets treated with individual endophytic bacterial strains. PR1, PR2, and PR4 gene expression levels of plantlets treated with Pseudomonas sp. Sn48 and Pantoea sp. Sa14 significantly increased after A. tumefaciens inoculation. The findings revealed the efficacy of the selected endophytic bacteria in triggering grapevine resistance against A. tumefaciens and the possible use of these strains as an alternative to chemical control methods in grapevine crown gall disease management.

The chemoselectivity and stereospecificity of the addition of the morpholine and the meta-chloroperoxybenzoic acid (m-CPBA) onto 9α-hydroxyparthenolide were studied using Density Functional Theory (DFT) calculations with the B3LYP/6-311+G(d,p) computational level within the Molecular Electron Density Theory (MEDT), to demonstrate the key role of the Global Electron Density Transfer (GEDT) and to examine the polar character of these reactions. This work is divided into two parts; the first part concerns the reaction between the morpholine and the 9α-hydroxyparthenolide. The second part deals with the epoxidation of the 9α-hydroxyparthenolide by m-CPBA followed by the addition of the morpholine to the major product resulting from the epoxidation step. The obtained results show that the reaction between the morpholine and the 9α-hydroxyparthenolide takes place on the double bond C3=C4. On the other hand, when 9α-hydroxyparthenolide is attacked by m-CPBA, the epoxidation reaction is carried out on the double bond C1=C2.

This work aims to treat olive mill wastewater (OMWW) by infiltration percolation in different columns containing filtration sand, granular activated carbon, and lime, and thus followed by biological treatment using the soil microorganisms to the treatment that will give the best results. The optimum removal efficiency was obtained using granular activated carbon column mixed with 15% of lime with percentages removal of 39.33, 60.28, 53.17 and 88.74% for biological oxygen demand (BOD5), chemical oxygen demand (COD), polyphenols and suspended matter respectively. Aerobic treatment 30 days of OMWW obtained from the column of activated carbon mixed with 15% of lime, neutralized and diluted 15 times with distilled water was investigated. The results showed a significant percentage reduction of 79.78, 69.43, and 60.67%, respectively, for BOD5, COD, and polyphenols. The global removal percentages after the two successive treatments were 87.86% for COD, 87.39% for BOD5 and 81.59% for polyphenols compounds. Fourier Transformed Infrared spectroscopy analysis of crude OMWW, infiltrated percolated and biologically treated, showed a difference between the spectra that manifests by the reduction of the spectrum intensity bands after each treatment stage, which confirmed the analytical results. Soil microorganisms have shown their biodegradation efficiency of organic matter and polyphenols of these much-polluted effluents under aerobic conditions. The results indicated that the pretreatment of raw olive mill wastewater could be realized before biological treatment to obtain a satisfactory reduction.