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Magnetic chitosan nanoparticles, synthesized by in situ precipitation, have been used as adsorbents to remove sulfamethoxazole (SMX), a sulfonamide antibiotic dangerous due to its capacity to enter ecosystems. The adsorption of SMX has been carried out in the presence of tertiary wastewaters from a depuration plant to obtain more realistic results. The effect of pH on the adsorption capacity significantly changed when carrying out the experiments in the presence of wastewater. This change has been explained while taking into account the charge properties of both the antibiotic and the magnetic chitosan. The composition of wastewaters has been characterized and discussed as regards its effect on the adsorption capacity of the magnetic chitosan. The models of Elovich and Freundlich have been selected to describe the adsorption kinetics and the adsorption isotherms, respectively. The analysis of these models has suggested that the adsorption mechanism is based on strong chemical interactions between the SMX and the magnetic chitosan, leading to the formation of an SMX multilayer. [ABSTRACT FROM AUTHOR]

Methanol is expected to be a possible solution for reducing global greenhouse gas emissions and minimizing the dependency on fossil fuels. This paper presents a systematic approach of methanol (MeOH) production from industrial waste gases including flue gas (FG) and coke oven gas (COG) that are considered an important threat to the environment. The impact of process parameters, including dimensional parameters (length, diameter, and number of tubes) and operational parameters (reactor temperature, pressure, and thermal fluid temperature) over the MeOH synthesis, are investigated by Aspen Plus. Firstly, the synthesis process is designed and optimized using syngas (SG) as a feed material. Secondly, by replacing the feed material with FG and COG, methanol production variability is investigated and demonstrated for the same optimized process. Afterward, an efficient heat exchange network system is developed for all three different processes using Aspen Energy Analyzer. The optimized dimensional parameters of the MeOH synthesis reactor are determined to be a length of 12 m, a diameter of 0.06 m, and 5000 tubes for achieving a conversion rate of 75%. Meanwhile, the optimized operational parameters are identified as a reactor temperature of 209   ° C , reactor pressure of 70 bar, and thermal fluid temperature of 196   ° C . Furthermore, the influence of the stoichiometric number (SN) on the process was observed with higher SN values resulting in increased hydrogen (H2) concentration and an improved forward reaction of MeOH synthesis, leading to higher conversion rates. The findings and insights gained from this study can serve further improvements and advancements in MeOH synthesis processes. [ABSTRACT FROM AUTHOR]

The study investigated the suitability of waste rubber powder (WRP) use as filler in adhesive formulation for plywood application. Melamine Urea Formaldehyde (MUF) was employed as resin for formulating the wood adhesive. To improve chemical properties and bonding quality of adhesive, WRP was treated by different chemicals like 20% nitric acid, 30% hydrogen peroxide and acetone solution. The treated WRP were analysed by XRD and it showed that inorganic compounds were removed and carbon was remained as major component under the treatment of 20% HNO3. The treatment improved the mechanical properties like shear strength and formaldehyde emission of plywood (high shear strength and low formaldehyde emission). The physico-chemical interaction between the wood, resin and filler was investigated using fourier transform infrared spectroscopic (FTIR) technique and the interactions among N-H of MUF and C=O of wood and WRP were identified. The morphology of wood-adhesive interface was studied by field emission scanning electron microscope (FESEM) and light microscope (LM). It showed that the penetration of adhesives and fillers through the wood pores was responsible for mechanical interlocking. Therefore, chemically treated WRP proved its potential use as filler in MUF based adhesive for making plywood.

Biofuels production is mostly oriented with fermentation process, which requires fermentable sugar as nutrient for microbial growth. Lignocellulosic biomass (LCB) represents the most attractive, low-cost feedstock for biofuel production, it is now arousing great interest. The cellulose that is embedded in the lignin matrix has an insoluble, highly-crystalline structure, so it is difficult to hydrolyze into fermentable sugar or cell protein. On the other hand, microbial lipid has been studying as substitute of plant oils or animal fat to produce biodiesel. It is still a great challenge to extract maximum lipid from microbial cells (yeast, fungi, algae) investing minimum energy.Electroporation (EP) of LCB results a significant increase in cell conductivity and permeability caused due to the application of an external electric field. EP is required to alter the size and structure of the biomass, to reduce the cellulose crystallinity, and increase their porosity as well as chemical composition, so that the hydrolysis of the carbohydrate fraction to monomeric sugars can be achieved rapidly and with greater yields. Furthermore, EP has a great potential to disrupt the microbial cell walls within few seconds to bring out the intracellular materials (lipid) to the solution. Therefore, this study aims to describe the challenges and prospect of application of EP technique in biofuels processing.

Bubbling fluidized bed (BFB) reactor is advantageous for synthesis gas or syngas production among other available gasifiers. In this study, a BFB gasifier has been designed, utilizing non-woody biomass (rice straw) and air as gasifying medium, to investigate the effect of equivalence ratio (ER), static bed height, and operating temperature on synthesis gas yield and gasification efficiency. To calculate various structural and operating parameters, a reaction chamber with a diameter of 10 cm and a bed material of 400-500 pm has been studied. Considering the minimum fluidization velocity, slugging velocity, and terminal velocity, the optimum operating velocity has been taken as 17.25 cm/s. The calculated optimum transport disengagement height (TDH) is 86 cm, and the freeboard height is approximately 116 cm. Thus, the overall height of the reactor has come up as 202 cm. Almost 80% carbon conversion efficiency (CCE) was achieved from this BFB reactor with an optimum ER value of 0.35 during rice straw gasification. The same gasifier results in a synthesis gas yield of 3.6 Nm³/kg with a lower heating value (LHV) of about 3.5 MJ/Nm³ at optimum ER value. Further scaling up this process based on the findings of this study for industrial-scale synthesis gas production can pave a way for bioenergy generation from non-woody biomass. [ABSTRACT FROM AUTHOR]

This study is aimed to evaluate the electricity generation from microbial fuel cell (MFC) and to analyze the microbial community structure of city wastewater and anaerobic sludge to enhance the MFC performance. MFCs, enriched with palm oil mill effluent (POME) were employed to harvest electricity by innoculating of Klebsiella oxytoca, collected from city wastewater and other microbes from anaerobic sludge (AS). The MFC showed maximum power density of 207.28 mW/m3 with continuous feeding of POME using microbes from AS. Subsequent replacement with Klebsiella oxytoca resulted maximum power density of 1236 mW/m3 by utilizing complex substrate POME which was six times higher as compared to MFC operated with AS. Based on Biolog gene III analysis, relatively higher abundance of Klebsiella oxytoca was detected in the city wastewater. Predominant microorganisms such as Gammaproteobacteria, Azospiraoryzae, Acetobacterperoxydans and Solimonasvariicoloris were isolated from palm oil anaerobic sludge as well as from biofilm of MFC. Enriched electrochemically active bacteria Klebsiella oxytoca showed better performance to generate electricity from complex POME substrates compare to AS. These results demonstrate that the power output of MFCs can be increased significantly using Klebsiella oxytoca.

Objective: The objective of this study was to develop a low-cost kit for the detection of subclinical mastitis (SCM) and to check its validity, reproducibility, and efficacy at the field level. Materials and Methods: A total of 550 quarter milk samples from crossbred dairy cows were collected, of which 400 milk samples were used to validate the newly developed BLRI mastitis test (BMT) kit to justify its efficacy as an individual test kit in detecting SCM based on somatic cell count (SCC) by direct microscopic count (DMC). The efficacy of the newly developed BMT was compared with the California Mastitis Test (CMT) kit. Another 150 milk samples were subjected to SCC determined by DMC and DCC (De Laval cell counter®) categorized by CMT and BMT scores. Results: A SCM test kit, namely, BMT kit was successfully developed in this study. The percentage accuracy of CMT and BMT were 76.75% and 75.75%; sensitivity 69.36% and 67.56%; specificity 85.95% and 85.85%; positive predictive value 86.03% and 85.71%; negative predictive value 69.23% and 68%, respectively. A p value of 0.001 was found for both CMT and BMT. However, CMT and BMT had no significant difference in sensitivity (p = 0.778). Average SCCs (cells/ml) determined by DCC and DMC, respectively, were mostly corresponded to the SCC ranges of both CMT and BMT scores. Conclusion: The newly developed BMT kit is an independent, cheap, farmer-friendly, first country made, and reliable SCM diagnostic test kit that can be used at field condition. [ABSTRACT FROM AUTHOR]

Objectives: The study was undertaken with the objectives to perform seromonitoring of Peste des Petits Ruminants (PPR) antibodies in goats vaccinated with PPR vaccine and molecular characterization of PPR virus (PPRV) from field cases in Bangladesh. Materials and Methods: Seromonitoring work was conducted in Char Kalibari, Mymensingh Sadar, Mymensingh. For this, a total of 50 goats were randomly selected and were divided into two groups; vaccinated (Group A; n = 25) and non-vaccinated (Group B; n = 25). The goats of both groups were again sub-divided into four age groups; (i) 0-6 months (n = 5), (ii) 6-12 months (n = 5), (iii) 12-24 months (n = 10), and (iv) >24 months (n = 5). Blood samples were collected on Day-0 and after 21 days of post-vaccination (DPV), and the sera were prepared. The sera were examined for the presence of antibodies against PPRV by competitive enzyme-linked immunosorbent assay. For molecular characterization, nasal swabs (n = 10) were collected from PPR infected goats in Jessore during PPR outbreak (February 2016). The causative agent, PPRV isolated from field cases were confirmed by N gene based on reverse transcription polymerase chain reaction (RT-PCR), followed by sequencing, phylogenetic analysis, and multiple sequence alignment analyses. Results: In the case of seromonitoring, the results revealed that before vaccination (at Day-0), overall, 44% (n = 22/50) goats were seropositive for PPRV. In Group A, 48% (n = 12/25) goats were seropositive, but after 21 DPV, 96% (n = 24/25) goats become seropositive. On the other hand, in Group B, 40% (n = 10/25) and 16% (n = 04/25) seropositive goats found at Day-0 and after 21 DPV, respectively, indicating that the antibody titer was increasing after vaccination and decreasing in convalescent goats. Out of 10 nasal swab samples, 40% (n = 4/10) was confirmed by RT-PCR targeting nucleocapsid (N gene). Phylogenetically, our isolate (KY039156/PPRV/BDG/Jes/2016) was similar to the other strains of PPRV under lineage IV. However, there was a unique amino acid substitution, where glycine (G) was recorded in place of arginine (R). The strain is closely related with other Chinese or Indian strains. The nucleotide sequence homology by NCBI BLAST search of the isolated strain ranged from 95% to 99% with other strains circulating in Bangladesh. Conclusion: The PPRV is prevailing in the Mymensingh and Jessore regions of Bangladesh. Effective control of PPR in goats may depend on vaccination with PPR vaccine. Molecular characterization of PPRV in Jessore reveals that the virus is differing from the strain prevalent in other regions of Bangladesh and the world. [ABSTRACT FROM AUTHOR]

Immobilized enzymes are increasingly used in enzymatic microreactors, to encourage applications in different fields: food industry, medical diagnostics, organic synthesis, drug discovery, biosensors. As a matter of facts, microfluidic systems offer many advantages over conventional packed-bed bioreactors, such as higher efficiency, feasibility of multi-enzyme systems, higher mechanical stability, reduced amounts of reagents required [Pirozzi et al., 2016]. In this study β-1,4-xylan obtained from hemicelluloses was used to obtain xylo-oligosaccharides (XOS), the only nutraceutical that can be produced from lignocellulosic biomass. XOS are considered non-digestible food ingredients, and their prebiotic effect of XOS on Bifidobacterium and Lactobacillus species has been recently demonstrated [Aachary et al., 2011; Broekaert et al., 2011; Nacos et al., 2006; Samanta et al, 2015; Vazquez]et al., 2000]. In addition XOS are stable at wide range of pH (2.5-8.0) and temperature (100 °C), they can stimulate the selective growth of the gut microflora, reduce the blood glucose and cholesterol, reduce the pro-carcinogenic enzymes in gastrointestinal tract, and enhance the mineral absorption from large intestine [Aachary et al., 2011; Broekaert et al., 2011; Nacos et al., 2006; Samanta et al, 2015; Vazquez]et al., 2000]. In this view, sol-gel methods were used for the physical entrapment of xylanase from T. lanuginosus. Due to the mild conditions usually adopted for the gel synthesis, enzymes could be added to the initial mixture of precursors and so entrapped within monolithic porous layers in capillary tubes [Pirozzi et al., 2016]. A suitable combination of sol-gel precursors was found for the simultaneous improvement of the monolith adhesion to the tubing internal surfaces and of the catalytic properties of the entrapped enzymes. Specific attention was devoted to the determination of operating conditions suitable to enhance enzyme stability as well as selectivity in terms of XOS produced. [ABSTRACT FROM AUTHOR]

The discharge of palm oil mill effluent (POME) on arable land causes large amounts of environmental distress due to its high concentration of phenolic compounds and chemical oxygen demand (COD). The approach of simultaneous microbial oil production and wastewater treatment is an attractive option to combine renewable energy production and environmental resilience. This study aims to produce cost effective microbial lipids using the oleaginous yeast Lipomyces starkeyi through the bioremediation of POME. A moderately dilute solution (50%) of POME showed higher microbial growth and lipid accumulation and offered a significantly higher degree of bioremediation. A lipid content of 21.32% was achieved with 50% POME, whereas the value was 15.14% for 25% POME. Three different techniques including ultrasonic treatment, Fenton's reagent and Fenton's + ultrasonic were employed to extract lipids from microbial biomass, and the maximum lipid concentration was obtained using the Fenton's + ultrasonic treatment. The degree of bioremediation was evaluated by the calculating seed germination index (GI) values. Higher GI values were observed for the 25% and 50% dilutions compared to undiluted (100%) POME. This combined approach can be a potential alternative technology that integrates bioremediation of POME with microbial lipid production. [ABSTRACT FROM AUTHOR]

Microbial oils are considered as alternative to vegetable oils or animal fats as biodiesel feedstock. Microalgae and oleaginous yeast are the main candidates of microbial oil producers' community. However, biodiesel synthesis from these sources is associated with high cost and process complexity. The traditional transesterification method includes several steps such as biomass drying, cell disruption, oil extraction and solvent recovery. Therefore, direct transesterification or in situ transesterification, which combines all the steps in a single reactor, has been suggested to make the process cost effective. Nevertheless, the process is not applicable for large-scale biodiesel production having some difficulties such as high water content of biomass that makes the reaction rate slower and hurdles of cell disruption makes the efficiency of oil extraction lower. Additionally, it requires high heating energy in the solvent extraction and recovery stage. To resolve these difficulties, this review suggests the application of antimicrobial peptides and high electric fields to foster the microbial cell wall disruption. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the synergistic or antagonistic interaction between oral dabigitran etexilate (Pradaxa) and some foods. Methods: Aqueous extracts of sweet orange, cabbage, ginger, green tea, garlic and pineapple were prepared and lyophilized, and total phenolic acids and flavonoid contents evaluated. The residues of the aqueous extracts were given daily to the rats (500 mg/kg dose, oral) 1 h after administration of dabigatran (1.83 mg/kg dose) for 14 days. Bleeding time, International Normalized Ratio (INR), prothrombin time (PT) as well as alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) in blood were measured. Results: Oral administration of Pradaxa with all the test food (except cabbage) significantly increased bleeding time, INR and PT. Pradaxa interaction with cabbage significantly decreased bleeding tendencies but the drug did not produce any major elevation of liver enzyme levels (ALT, AST and ALP). Conversely, significant elevation in ALP level was observed only after aqueous extract of ginger was administered with Pradaxa. Green tea and garlic significantly increased ALT and AST levels. Conclusion: Synergistic interaction occurrs between dabigatran etexilate with the selected foods, but interaction with cabbage antagonistic. [ABSTRACT FROM AUTHOR]

In this work, p-type CuFe2O4 was synthesized by sol gel method. The prepared CuFe2O4 was used as photocathode catalyst for photoelectrochemical (PEC) CO2 reduction. The XRD, UV-Visible Spectroscopy (UV-Vis), and Mott-Schottky (MS) experiments were done to characterize the catalyst. Linear sweep voltammetry (LSV) was employed to evaluate the visible light (λ>400 nm) effect of this catalyst for CO2 reduction. The band gap energy of the catalyst was calculated from the UV-Vis and was found 1.30 eV. Flat band potential of the prepared CuFe2O4 was also calculated and found 0.27 V versus Ag/AgCl. Under light irradiation in the CO2-saturated NaHCO3 solution, a remarkable current development associated with CO2 reduction was found during LSV for the prepared electrode from onset potential -0.89 V with a peak current emerged at -1.01 V (vs Ag/AgCl) representing the occurrence of CO2 reduction reaction. In addition, the mechanism of PEC was proposed for the photocathode where the necessity of a bias potential in the range of 0.27 to ~ -1.0 V vs Ag/AgCl was identified which could effectively inhibit the electron-hole (e-/h+) recombination process leading to an enhancement of CO2 reduction reactions. [ABSTRACT FROM AUTHOR]