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The authors are grateful to the “Ministerio de Economía y Competitividad” (Project CTQ2013-42006-R) for financial support., Se estudió la extracción de hemicelulosa de la madera de pino aplicando un tratamiento de autohidrólisis. Se realizó un diseño Se realizó un diseño experimental compuesto central utilizando diferentes temperaturas (150-190 °C) y tiempos (30-90 min) para seleccionar las condiciones de operación más favorables para maximizar la extracción de hemicelulosa y minimizar su degradación. su degradación. Esta fase líquida se analizó por HPLC para cuantificar oligosacáridos, monosacáridos y productos de degradación. La composición de la madera autohidrolizada se determinó y caracterizó mediante FTIR y TGA. Se extrajo el 60% de las hemicelulosas a una temperatura de 170 °C en 60 min, presentándose principalmente en forma oligomérica en la fase líquida, permaneciendo la fase sólida enriquecida en celulosa y lignina., The extraction of hemicellulose from pine wood was studied by applying autohydrolysis treatment. A central composite experimental design was carried out using different temperatures (150–190 °C) and times (30–90 min) to select the most favorable operating conditions for maximizing the extraction of hemicellulose and minimizing its degradation. This liquid phase was analyzed by HPLC to quantify oligosaccharides, monosaccharides and degradation products. The composition of the autohydrolyzed wood was determined and characterized, employing FTIR and TGA. Herein, 60% of the hemicelluloses were extracted under a temperature of 170 °C in 60 min, presenting primarily in an oligomeric form in the liquid phase, with the solid phase remaining enriched in cellulose and lignin., Ministerio de Economía y Competitividad, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

Congo red (CR) dye is a synthetic azo dye expansively used in the textile industry, is discharged to aquatic environments, and is toxic to humans and aquatic flora. The performance of cationic amino-modified banana leaves (CMBL) for CR dye sequestration was evaluated first time in this study. The surface modification of CMBL was analyzed using Scanning electron microscope (SEM) and Fourier transform infrared (FTIR) spectrum and compared with raw banana leaves powder (RBL). The optimum condition for CR dye adsorption using CMBL was optimized using Central Composite Design (CCD) by investigating four critical operating parameters: contact time, pH, RBL/CMBL doses, and initial CR dye concentrations. The proposed model (quadratic) was acceptable due to the high values of correlation coefficients R2 (0.96) and adjusted R2 (0.92). The CMBL exhibited maximum removal efficiency of 76.82% towards CR dye at pH 3 compared to RBL, i.e., 19.63%. Electrostatic interaction and hydrogen bonding were the primary removal mechanisms for the CR dye adsorption process using CMBL. Freundlich isotherm and pseudo-second-order kinetic model exhibited a strong correlation for experimental data and reported a correlation coefficient (R2) of more than 0.99. In addition, CMBL showed excellent reusability for the adsorption of CR dye even after three consecutive adsorption-desorption experiments., QC 20231031

The enzymatic hydrolysis of a cellulose-bearing substrate such as green seaweed Ulva fasciata for the release of reducing sugars for subsequent conversion to bioethanol is generating considerable research interest. However, a major challenge in this process is the cost of enzymes. Crude enzyme extracts from Aspergillus inseitus isolated from indigenous U. fasciata was employed in this study to compare its hydrolytic efficiency with commercial cellulase CTec 2. The aim of the study was to model and optimize the hydrolysis process to predict and determine the concentration of reducing sugars obtained using response surface methodology with the application of the statistical tool, central composite design. Two most important influencing process parameters—hydrolysis time and enzyme dosage—were varied and used to conduct the optimization. The results showed that an optimal enzyme dosage of 0.25 U/g DM could yield a maximum reducing sugar concentration of 1.61 g/L at 6 h hydrolysis time for the commercial enzyme CTec 2 and 0.61 g/L at 12 h for enzyme extracts from A. inseitus, making the hydrolytic efficiency of CTec 2 only approximately 3 times better than crude enzyme extracts from A. inseitus based on reducing sugar concentration. A satisfactory coefficient of R2 of 0.9415 and 0.9493 for A. inseitus and CTec 2 respectively was obtained for the models which were experimentally verified. Careful concentration and purification of the crude enzyme extract from A. inseitus could make it an effective cellulase for hydrolysis processes resulting in cost reduction.

Lipophilic marine biotoxins (LMBs) are one of the main risks associated with the consumption of mussels and oysters. Sanitary and analytical control programs are developed to detect the occurrence of these toxins in seafood before they reach toxic levels. To ensure quick results, methods must be easy and fast to perform. In this work, we demonstrated that incurred samples were a viable alternative to validation and internal quality control studies for the analysis of LMBs in bivalve mollusks. These samples were used to optimize, validate, and monitor a simple and fast ultrasound-assisted extraction (UAE) procedure. An internal quality control material containing okadaic acid (227 ± 46 µg kg-1) was produced and characterized. This material had its homogeneity and stability verified and was included as a quality control in all batches of analytical routine. Besides, a sample pooling protocol for extracts analysis was developed, based on tests for COVID-19. Up to 10 samples could be analyzed simultaneously, reducing the instrumental time of analysis by up to 80%. The UAE and sample pooling approaches were then applied to more than 450 samples, of which at least 100 were positive for the okadaic acid group of toxins.

Kraft lignin, a side-stream from the pulp and paper industry, can be modified by laccases for the synthesis of high added-value products. This work aims to study different laccase sources, including a bacterial laccase from Streptomyces ipomoeae (SiLA) and a fungal laccase from Myceliophthora thermophila (MtL), for kraft lignin polymerization. To study the influence of some variables in these processes, a central composite design (CCD) with two continuous variables (enzyme concentration and reaction time) and three levels for each variable was used. The prediction of the behavior of the output variables (phenolic content and molecular weight of lignins) were modelled by means of response surface methodology (RSM). Moreover, characterization of lignins was performed by Fourier-transform infrared (FTIR) spectroscopy and different nuclear magnetic resonance (NMR) spectroscopy techniques. In addition, antioxidant activity was also analyzed. Results showed that lignin polymerization (referring to polymerization as lower phenolic content and higher molecular weight) occurred by the action of both laccases. The enzyme concentration was the most influential variable in the lignin polymerization reaction within the range studied for SiLA laccase, while the most influential variable for MtL laccase was the reaction time. FTIR and NMR characterization analysis corroborated lignin polymerization results obtained from the RSM.

Kraft lignin, a side-stream from the pulp and paper industry, can be modified by laccases for the synthesis of high added-value products. This work aims to study different laccase sources, including a bacterial laccase from Streptomyces ipomoeae (SiLA) and a fungal laccase from Myceliophthora thermophila (MtL), for kraft lignin polymerization. To study the influence of some variables in these processes, a central composite design (CCD) with two continuous variables (enzyme concentration and reaction time) and three levels for each variable was used. The prediction of the behavior of the output variables (phenolic content and molecular weight of lignins) were modelled by means of response surface methodology (RSM). Moreover, characterization of lignins was performed by Fourier-transform infrared (FTIR) spectroscopy and different nuclear magnetic resonance (NMR) spectroscopy techniques. In addition, antioxidant activity was also analyzed. Results showed that lignin polymerization (referring to polymerization as lower phenolic content and higher molecular weight) occurred by the action of both laccases. The enzyme concentration was the most influential variable in the lignin polymerization reaction within the range studied for SiLA laccase, while the most influential variable for MtL laccase was the reaction time. FTIR and NMR characterization analysis corroborated lignin polymerization results obtained from the RSM.

According to recent studies, the anaerobic digestion of strawberry extrudate is a promising option with potential in the berry industry biorefinery. However, the lack and/or unbalance of concentrations of metals in some agro-industrial residues could hamper methane production during the anaerobic digestion of these kinds of wastes. In this study, a fractional factorial design was applied to screen the supplementation requirements regarding six metals (Co, Ni, Fe, Cu, Mn, and Zn) for methane production from strawberry extrudate (SE). The logistic model was used to fit the experimental data of methane production-time. It allowed identifying two different stages in the anaerobic process and obtaining the kinetic parameters for each step. Maximum methane production obtained in the first (Bmax) kinetic stage, the methane production in the second stage (P), and the maximum methane production rates (Rmax) concluded a statistically significant effect for Ni and Zn. The second set of experiments was carried out with Ni and Zn through a central composite design to study the concentration effect in the anaerobic digestion process of the strawberry extrudate. The parameters P and Rmax demonstrated a positive interaction between Ni and Zn. Although, Bmax did not prove a statistically significant effect between Ni and Zn.

CRUE-CSIC (Acuerdos Transformativos 2022), The lignocellulosic materials are promising feedstock to produce biofuels and bioproducts in the biorefnery framework. However, a pretreatment step is required to disrupt lignin-carbohydrate complex. In this work, the fractionation of Pinus radiata wood into its main components, cellulose-rich delignifed solid, recovered lignin after precipitation, and solublein-black liquor hemicellulose, was studied. For this purpose, an organosolv process employing ethanol/water mixture as solvent in absence of a catalyst was carried out. The efects of operating conditions on delignifed solid were evaluated by using a 23 central composite experimental design, being the responses delignifed solid yield, delignifcation degree, hemicellulose content, and glucan content. The variables studied were temperature (170–200 °C), time (50–100 min), and ethanol concentration (40–60%). The increase of organosolv severity (temperature and time) and reduction of ethanol concentration favor the glucan enrichment of delignifed solid, due to lignin removal and hemicellulose solubilization. A glucan content of more than 66% is obtained by applying temperature higher than 195 °C and time longer than 90 min, when 40 wt% alcohol concentration is used. The liquid fraction obtained during the organosolv process (black liquors) was used to recover lignin and hemicellulosic fractions solubilized. Furthermore, hemicellulose and lignin content of delignifed solid was correlated with the thermal stability measured as T10%., Ministerio de Economía y Competitividad (MINECO), Comunidad de Madrid, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

There has been an over-flogged attention given to propositions on how one can make good choice of the existing axial points rather than procedural techniques for constructing axial points about the existing axial points. In order to curb this oversight, this work has constructed axial points about the standard axial points. The construction has given rise to * = 0.99k (where k is the number of factors) in  comparison to the standard axial points  =     (where f is the number of factorial points).   Both axial points have been implemented on a central composite design used for maximizing a  four-factor process. The constructed axial points produced yields of  about 87.211%, better than  the yield of 87.187% produced by the standard axial points. Furthermore, the central composite  design resulting from the constructed axial points satisfied the D-, A- and  E-optimality criteria  in comparison to that obtained from the standard or existing axial points.

Recent advances in glycobiotechnology show that bacterial exopolysaccharides (EPS) presenting glycosaminoglycan (GAG)-like properties can provide a valuable source of bio-active macromolecules for industrial applications. The HE800 EPS, named diabolican, is a marine-derived anionic high-molecular-weight polysaccharide produced by Vibrio diabolicus CNCM I-1629 which displays original structural features close to those of hyaluronic acid. We investigated the impact of carbon and nitrogen substrates on both Vibrio diabolicus growth and diabolican production. Both substrates were screened by a one-factor-at-a-time method, and experimental designs were used to study the effect of glucose, mannitol, and ammonium acetate various concentrations. Results showed that the medium composition affected not only the bacterium growth and EPS yield, but also the EPS molecular weight (MW). EPS yields of 563 and 330 mg L−1 were obtained in the presence of 69.3 g L−1 glucose and 24.6 g L−1 mannitol, respectively, both for 116.6 mM ammonium acetate. MW was the highest, with 69.3 g L−1 glucose and 101.9 mM ammonium acetate (2.3 × 106 g mol−1). In parallel, the bacterial maximum specific growth rate was higher when both carbon and nitrogen substrate concentrations were low. This work paves the way for the optimization of marine exopolysaccharide production of great interest in the fields of human health and cosmetics

Recent advances in glycobiotechnology show that bacterial exopolysaccharides (EPS) presenting glycosaminoglycan (GAG)-like properties can provide a valuable source of bio-active macromolecules for industrial applications. The HE800 EPS, named diabolican, is a marine-derived anionic high-molecular-weight polysaccharide produced by Vibrio diabolicus CNCM I-1629 which displays original structural features close to those of hyaluronic acid. We investigated the impact of carbon and nitrogen substrates on both Vibrio diabolicus growth and diabolican production. Both substrates were screened by a one-factor-at-a-time method, and experimental designs were used to study the effect of glucose, mannitol, and ammonium acetate various concentrations. Results showed that the medium composition affected not only the bacterium growth and EPS yield, but also the EPS molecular weight (MW). EPS yields of 563 and 330 mg L−1 were obtained in the presence of 69.3 g L−1 glucose and 24.6 g L−1 mannitol, respectively, both for 116.6 mM ammonium acetate. MW was the highest, with 69.3 g L−1 glucose and 101.9 mM ammonium acetate (2.3 × 106 g mol−1). In parallel, the bacterial maximum specific growth rate was higher when both carbon and nitrogen substrate concentrations were low. This work paves the way for the optimization of marine exopolysaccharide production of great interest in the fields of human health and cosmetics

There has been an over-flogged attention given to propositions on how one can make good choice of the existing axial points rather than procedural techniques for constructing axial points about the existing axial points. In order to curb this oversight, this work has constructed axial points about the standard axial points. The construction has given rise to * = 0.99k (where k is the number of factors) in  comparison to the standard axial points  =     (where f is the number of factorial points).   Both axial points have been implemented on a central composite design used for maximizing a  four-factor process. The constructed axial points produced yields of  about 87.211%, better than  the yield of 87.187% produced by the standard axial points. Furthermore, the central composite  design resulting from the constructed axial points satisfied the D-, A- and  E-optimality criteria  in comparison to that obtained from the standard or existing axial points.

Plant-based sustainable and nutritional food are a recent, growing trend setting out new opportunities for operators in the food value chain to ensure and reduce emissions from the global food production. Baobab (Adansonia digitata L.) fruit pulp, approved as a novel food, is rich in dietary fibres, antioxidants, and minerals. Towards the commercialization of baobab fruit pulp, to meet the demand for plant based sustainable food alternatives, Baofraiche, a cookable sauce, based on baobab fruit pulp has been developed and presented. This thesis reviews how the viscosity of the Baofraiche dispersion is affected during heating and by adding external ingredients. A Central Composite Design with three factors, pectin, Agar Agar and protein have been used. Thus, this experiment have been conducted to contribute to knowledge so that an optimal prototype for Baofraiche can be developed. Findings suggest that the viscosity of the Baofraiche decrease at higher temperatures. Pectin and Agar Agar, two different types of polysaccharides, affect the dispersion in different ways. Hence, the conclusion can be drawn that it is not possible to add any polysaccharide and predict that they will have the same effect on the dispersion during heating. Added protein, in combination with the other added factors, have a decreasing effect on the viscosity. Therefore, these factors should not be added together if a higher viscosity is required. Further studies should examine the optimal dispersion of Baofraiche based on the finding in this thesis. The overall conclusion is that Baofraiche is cookable and disperse well in a food system.

There has been an over-flogged attention given to propositions on how one can make good choice of the existing axial points rather than procedural techniques for constructing axial points about the existing axial points. In order to curb this oversight, this work has constructed axial points about the standard axial points. The construction has given rise to * = 0.99k (where k is the number of factors) in  comparison to the standard axial points  =     (where f is the number of factorial points).   Both axial points have been implemented on a central composite design used for maximizing a  four-factor process. The constructed axial points produced yields of  about 87.211%, better than  the yield of 87.187% produced by the standard axial points. Furthermore, the central composite  design resulting from the constructed axial points satisfied the D-, A- and  E-optimality criteria  in comparison to that obtained from the standard or existing axial points.

There has been an over-flogged attention given to propositions on how one can make good choice of the existing axial points rather than procedural techniques for constructing axial points about the existing axial points. In order to curb this oversight, this work has constructed axial points about the standard axial points. The construction has given rise to * = 0.99k (where k is the number of factors) in  comparison to the standard axial points  =     (where f is the number of factorial points).   Both axial points have been implemented on a central composite design used for maximizing a  four-factor process. The constructed axial points produced yields of  about 87.211%, better than  the yield of 87.187% produced by the standard axial points. Furthermore, the central composite  design resulting from the constructed axial points satisfied the D-, A- and  E-optimality criteria  in comparison to that obtained from the standard or existing axial points.

A metamodeling technique based on Bivariate Cut High Dimensional Model Representation (Bivariate Cut HDMR) is implemented for a semiconductor packaging design problem with 10 design variables. Bivariate Cut-HDMR constructs a metamodel by considering only up to second-order interactions. The implementation uses three uniformly distributed sample points (s = 3) with quadratic spline interpolation to construct the component functions of Bivariate Cut-HDMR, which can be used to make a direct comparison with a metamodel based on Central Composite Design (CCD). The performance of Bivariate Cut-HDMR is evaluated by two well-known error metrics: R-squared and Relative Average Absolute Error (RAAE). The results are compared with the performance of CCD. Bivariate Cut HDMR does not compromise the accuracy compared to CCD, although the former uses only one-fifth of sample points (201 sample points) required by the latter (1045 sample points). The sampling schemes and the predictions of cut-planes and boundary-planes are discussed to explain possible reasons for the outstanding performance of Bivariate Cut HDMR.

The nutritional quality of animal products is strongly related to their fatty acid content and composition. Nowadays, attention is paid to the possibility of producing healthier foods of animal origin by intervening in animal feed. In this field, the use of condensed tannins as dietary supplements in animal nutrition is becoming popular due to their wide range of biological effects related, among others, to their ability to modulate the rumen biohydrogenation and biofortify, through the improvement of the fatty acids profile, the derivate food products. Unfortunately, tannins are characterized by strong astringency and low bioavailability. These disadvantages could be overcome through the microencapsulation in protective matrices. With this in mind, the optimal conditions for microencapsulation of a polyphenolic extract rich in condensed tannins by spray drying using a blend of maltodextrin (MD) and gum Arabic (GA) as shell material were investigated. For this purpose, after the extract characterization, through spectrophotometer assays and ultra-high-performance liquid chromatography-quadrupole time-of-flight (UHPLC-QTOF) mass spectrometry, a central composite design (CCD) was employed to investigate the combined effects of core:shell and MD:GA ratio on the microencapsulation process. The results obtained were used to develop second-order polynomial regression models on different responses, namely encapsulation yield, encapsulation efficiency, loading capacity, and tannin content. The formulation characterized by a core:shell ratio of 1.5:5 and MD:GA ratio of 4:6 was selected as the optimized one with a loading capacity of 17.67%, encapsulation efficiency of 76.58%, encapsulation yield of 35.69%, and tannin concentration of 14.46 g/100 g. Moreover, in vitro release under varying pH of the optimized formulation was carried out with results that could improve the use of microencapsulated condensed tannins in animal nutrition for the biofortification of derivates.

The use of low-field magnetic resonance imaging (LF-MRI) scanners has increased in recent years. The low economic cost in comparison to high-field (HF-MRI) scanners and the ease of maintenance make this type of scanner the best choice for nonmedical purposes. However, LF-MRI scanners produce low-quality images, which encourages the identification of optimization procedures to generate the best possible images. In this paper, optimization of the image acquisition procedure for an LF-MRI scanner is presented, and predictive models are developed. The MRI acquisition procedure was optimized to determine the physicochemical characteristics of pork loin in a nondestructive way using MRI, feature extraction algorithms and data processing methods. The most critical parameters (relaxation times, repetition time, and echo time) of the LF-MRI scanner were optimized, presenting a procedure that could be easily reproduced in other environments or for other purposes. In addition, two feature extraction algorithms (gray level co-occurrence matrix (GLCM) and one point fractal texture algorithm (OPFTA)) were evaluated. The optimization procedure was validated by using several evaluation metrics, achieving reliable and accurate results (r >0:85; weighted absolute percentage error (WAPE) lower than 0.1%; root mean square error of prediction (RMSEP) lower than 0.1%; true standard deviation (TSTD) lower than 2; and mean absolute error (MAE) lower than 2). These results support the high degree of feasibility and accuracy of the optimized procedure of LF-MRI acquisition. No other papers present a procedure to optimize the image acquisition process in LF-MRI. Eventually, the optimization procedure could be applied to other LF-MRI systems.

The use of low-field magnetic resonance imaging (LF-MRI) scanners has increased in recent years. The low economic cost in comparison to high-field (HF-MRI) scanners and the ease of maintenance make this type of scanner the best choice for nonmedical purposes. However, LF-MRI scanners produce low-quality images, which encourages the identification of optimization procedures to generate the best possible images. In this paper, optimization of the image acquisition procedure for an LF-MRI scanner is presented, and predictive models are developed. The MRI acquisition procedure was optimized to determine the physicochemical characteristics of pork loin in a nondestructive way using MRI, feature extraction algorithms and data processing methods. The most critical parameters (relaxation times, repetition time, and echo time) of the LF-MRI scanner were optimized, presenting a procedure that could be easily reproduced in other environments or for other purposes. In addition, two feature extraction algorithms (gray level co-occurrence matrix (GLCM) and one point fractal texture algorithm (OPFTA)) were evaluated. The optimization procedure was validated by using several evaluation metrics, achieving reliable and accurate results (r >0:85; weighted absolute percentage error (WAPE) lower than 0.1%; root mean square error of prediction (RMSEP) lower than 0.1%; true standard deviation (TSTD) lower than 2; and mean absolute error (MAE) lower than 2). These results support the high degree of feasibility and accuracy of the optimized procedure of LF-MRI acquisition. No other papers present a procedure to optimize the image acquisition process in LF-MRI. Eventually, the optimization procedure could be applied to other LF-MRI systems.

The present study reports a multivariable optimization of ultrasound-assisted extraction of phenolic compounds from arrayan leaves. The parameters ethanol percentage in extraction solvent, temperature and extraction time, and mass to solvent ratio were optimized applying full factorial and central composite designs. According to the models, the optimal extraction conditions were: 42% of ethanol, extraction time of 27 min, extraction temperature of 50ºC and a mass to solvent ratio of 1:33.4 g mL-1. Under these conditions, a total phenolic content (TPC) of 128.16±1.18 and 593.64±6.49 mg of gallic acid equivalent per g of dry weight (DW) were determined in raw extract (RE) and polyphenols-rich extract (PRE), which was obtained by semi-preparative chromatography on XAD-7 column. Antioxidant capacity determined via FRAP analysis showed values of 1349.53±28.99 and 6175.47±127.64 µmol Trolox equivalent per g of DW for RE and PRE, and DPPH IC50 values of 831.40±0.80 and 132.21±2.51 µg mL-1, respectively. Polyphenols profile analyzed by liquid chromatography-mass spectrometry showed the presence of quercetin 3-ß-D-glucoside, myricetin, quercetin, kaempferol 3-glucoside and gallic acid; the latter compounds are reported for the first time in arrayan leaves. Due to the presence of polyphenols, antiviral activity was assayed over norovirus and hepatitis A showing a significant dose-dependent effect.

The interest in the study of polyphenols has grown considerably in recent years due to its high capacity to scavenge free radicals associated with various diseases. For this reason, the aim of this work was to obtain and characterize phenolic compounds from Justicia spicigera Schltdl by ultrasound-assisted extraction. The extracts were characterized in terms of the total phenolic content (Folin-Ciocalteu method), antioxidant activity (ferric-reducing/antioxidant power) and free radical scavenging activity (2,2-diphenyl-1-picrylhydrazyl free radical method). The response surface methodology (RSM) was used to evaluate the effect of the solvent (water/ethanol) and the extraction time, on the total phenolic content and antioxidant properties. The analysis of variance (ANOVA) indicated that the concentration of water in the solvent mixture significantly affected the yield of the compounds, as well as the antioxidant and antiradical activities. According to the RSM, the optimal extraction conditions are 25% water in the solvent mixture and a sonication time of 16 min., El interés en el estudio de los polifenoles ha crecido de manera considerable en los últimos años debido a su alta capacidad para atrapar radicales libres asociados con diversas enfermedades. Por este motivo, el objetivo del presente trabajo fue obtener y caracterizar los compuestos fenólicos de Justicia spicigera Schltdl. mediante extracción asistida por ultrasonido. A los extractos, se les determinó el contenido fenólico total (método de Folin-Ciocalteu), actividad antioxidante (potencial antioxidante/reductor del hierro) y actividad secuestradora de radicales libres (método del radical libre 2,2-difenil-2-picrilhidrazil). La metodología de superficie de respuesta (MSR) se empleó para evaluar el efecto del disolvente (agua/etanol) y el tiempo de extracción, en el contenido de fenoles totales y las propiedades antioxidantes. El análisis de varianza (ANOVA) indicó que la concentración de agua en la mezcla del disolvente afectó de manera importante el rendimiento de los compuestos, así como la actividad antioxidante y antiradical. De acuerdo con la MSR, las condiciones óptimas para la extracción son 25% de agua en la mezcla del disolvente y un tiempo de sonicación de 16 minutos.

The interest in the study of polyphenols has grown considerably in recent years due to its high capacity to scavenge free radicals associated with various diseases. For this reason, the aim of this work was to obtain and characterize phenolic compounds from Justicia spicigera Schltdl by ultrasound-assisted extraction. The extracts were characterized in terms of the total phenolic content (Folin-Ciocalteu method), antioxidant activity (ferric-reducing/antioxidant power) and free radical scavenging activity (2,2-diphenyl-1-picrylhydrazyl free radical method). The response surface methodology (RSM) was used to evaluate the effect of the solvent (water/ethanol) and the extraction time, on the total phenolic content and antioxidant properties. The analysis of variance (ANOVA) indicated that the concentration of water in the solvent mixture significantly affected the yield of the compounds, as well as the antioxidant and antiradical activities. According to the RSM, the optimal extraction conditions are 25% water in the solvent mixture and a sonication time of 16 min., El interés en el estudio de los polifenoles ha crecido de manera considerable en los últimos años debido a su alta capacidad para atrapar radicales libres asociados con diversas enfermedades. Por este motivo, el objetivo del presente trabajo fue obtener y caracterizar los compuestos fenólicos de Justicia spicigera Schltdl. mediante extracción asistida por ultrasonido. A los extractos, se les determinó el contenido fenólico total (método de Folin-Ciocalteu), actividad antioxidante (potencial antioxidante/reductor del hierro) y actividad secuestradora de radicales libres (método del radical libre 2,2-difenil-2-picrilhidrazil). La metodología de superficie de respuesta (MSR) se empleó para evaluar el efecto del disolvente (agua/etanol) y el tiempo de extracción, en el contenido de fenoles totales y las propiedades antioxidantes. El análisis de varianza (ANOVA) indicó que la concentración de agua en la mezcla del disolvente afectó de manera importante el rendimiento de los compuestos, así como la actividad antioxidante y antiradical. De acuerdo con la MSR, las condiciones óptimas para la extracción son 25% de agua en la mezcla del disolvente y un tiempo de sonicación de 16 minutos.

The interest in the study of polyphenols has grown considerably in recent years due to its high capacity to scavenge free radicals associated with various diseases. For this reason, the aim of this work was to obtain and characterize phenolic compounds from Justicia spicigera Schltdl by ultrasound-assisted extraction. The extracts were characterized in terms of the total phenolic content (Folin-Ciocalteu method), antioxidant activity (ferric-reducing/antioxidant power) and free radical scavenging activity (2,2-diphenyl-1-picrylhydrazyl free radical method). The response surface methodology (RSM) was used to evaluate the effect of the solvent (water/ethanol) and the extraction time, on the total phenolic content and antioxidant properties. The analysis of variance (ANOVA) indicated that the concentration of water in the solvent mixture significantly affected the yield of the compounds, as well as the antioxidant and antiradical activities. According to the RSM, the optimal extraction conditions are 25% water in the solvent mixture and a sonication time of 16 min., El interés en el estudio de los polifenoles ha crecido de manera considerable en los últimos años debido a su alta capacidad para atrapar radicales libres asociados con diversas enfermedades. Por este motivo, el objetivo del presente trabajo fue obtener y caracterizar los compuestos fenólicos de Justicia spicigera Schltdl. mediante extracción asistida por ultrasonido. A los extractos, se les determinó el contenido fenólico total (método de Folin-Ciocalteu), actividad antioxidante (potencial antioxidante/reductor del hierro) y actividad secuestradora de radicales libres (método del radical libre 2,2-difenil-2-picrilhidrazil). La metodología de superficie de respuesta (MSR) se empleó para evaluar el efecto del disolvente (agua/etanol) y el tiempo de extracción, en el contenido de fenoles totales y las propiedades antioxidantes. El análisis de varianza (ANOVA) indicó que la concentración de agua en la mezcla del disolvente afectó de manera importante el rendimiento de los compuestos, así como la actividad antioxidante y antiradical. De acuerdo con la MSR, las condiciones óptimas para la extracción son 25% de agua en la mezcla del disolvente y un tiempo de sonicación de 16 minutos.

Threats due to insufficient, inadequate and costlier methods of treating contaminants such as arsenic have emphasized the significance of optimizing and managing the processes adopted. This study was aimed at the complete elimination of arsenic from an aqueous medium with minimum energy consumption using the electrocoagulation process. Arsenic removal around 95% was rapidly attained for optimized conditions having a pH of 7, 0.46 A current intensity, 10 mg/L initial concentration and only 2 min of applied time duration using the energy of 3.1 watt-hour per gram of arsenic removed. Low values of applied current for longer durations resulted in the complete removal of arsenic with low energy consumption. Various hydroxide complexes including ferrous hydroxide and ferric hydroxide assisted in the removal of arsenic by adsorption along with co-precipitation. Surface models obtained were checked and found with a reasonably good fit having high values of coefficient of determination of 0.933 and 0.980 for removal efficiency and energy consumption, respectively. Adsorption was found to follow pseudo-first-order kinetics. Multivariate optimization proved it as a low-cost effective technology having an operational cost of 0.0974 Indian rupees (equivalent to USD 0.0013) per gram removal of arsenic. Overall, the process was well optimized using CCD based on response surface methodology., Threats due to insufficient, inadequate and costlier methods of treating contaminants such as arsenic have emphasized the significance of optimizing and managing the processes adopted. This study was aimed at the complete elimination of arsenic from an aqueous medium with minimum energy consumption using the electrocoagulation process. Arsenic removal around 95% was rapidly attained for optimized conditions having a pH of 7, 0.46 A current intensity, 10 mg/L initial concentration and only 2 min of applied time duration using the energy of 3.1 watt-hour per gram of arsenic removed. Low values of applied current for longer durations resulted in the complete removal of arsenic with low energy consumption. Various hydroxide complexes including ferrous hydroxide and ferric hydroxide assisted in the removal of arsenic by adsorption along with co-precipitation. Surface models obtained were checked and found with a reasonably good fit having high values of coefficient of determination of 0.933 and 0.980 for removal efficiency and energy consumption, respectively. Adsorption was found to follow pseudo-first-order kinetics. Multivariate optimization proved it as a low-cost effective technology having an operational cost of 0.0974 Indian rupees (equivalent to USD 0.0013) per gram removal of arsenic. Overall, the process was well optimized using CCD based on response surface methodology.

The optimal conditions for the reduction of COD and NH3-N using cockle shells (CS) from a stabilised landfill effluent were analyzed. The influence of two variables (adsorbent dosage and pH) were analysed through the application of response surface methodology (RSM) and central composite design (CCD). Quadratic models were developed for the removals of COD and NH3-N parameters. The optimum conditions for removal of 65.6% and 53.6% for COD and NH3-N respectively was achieved at pH 6.34, adsorbent dosage of 20.21 g having 0.888 desirability value. The model F-value obtained for NH3-N removal Prob. > F value of 0.0001 with F-value of 104.21 was obtained. Similarly the Prob. > F value of < 0.0001 for COD with F-value of 82.74 was obtained, these P-values confirmed the significance of the model. The predicted response versus the experimental response depicted that the experimental data were relatively close to the predicted data. Thus, the generated models significantly enclosed the correlation between the process variables and the response.   GMT Detect languageAfrikaansAlbanianArabicArmenianAzerbaijaniBasqueBelarusianBengaliBosnianBulgarianCatalanCebuanoChichewaChinese (Simplified)Chinese (Traditional)CroatianCzechDanishDutchEnglishEsperantoEstonianFilipinoFinnishFrenchGalicianGeorgianGermanGreekGujaratiHaitian CreoleHausaHebrewHindiHmongHungarianIcelandicIgboIndonesianIrishItalianJapaneseJavaneseKannadaKazakhKhmerKoreanLaoLatinLatvianLithuanianMacedonianMalagasyMalayMalayalamMalteseMaoriMarathiMongolianMyanmar (Burmese)NepaliNorwegianPersianPolishPortuguesePunjabiRomanianRussianSerbianSesothoSinhalaSlovakSlovenianSomaliSpanishSundaneseSwahiliSwedishTajikTamilTeluguThaiTurkishUkrainianUrduUzbekVietnameseWelshYiddishYorubaZulu AfrikaansAlbanianArabicArmenianAzerbaijaniBasqueBelarusianBengaliBosnianBulgarianCatalanCebuanoChichewaChinese (Simplified)Chinese (Traditional)CroatianCzechDanishDutchEnglishEsperantoEstonianFilipinoFinnishFrenchGalicianGeorgianGerm

Ultrasonic-assisted extraction (UAE) was applied to extract total carotenoids from dried peach palm peel using soy oil as extraction solvent. Optimization of UAE parameters of total carotenoid extraction from dried peel was done using Response Surface Methodology (RSM) and Central Composite Design (CCD). The extraction parameters were temperature, extraction time and solid to solvent ratio. The optimum UAE conditions were 48°C, extraction time of 28 min, and solid to solvent ratio of 0.0037 g/mL, with a predicted carotenoids content of 151.50 mg/100 g dried peel. To validate the optimized model, the experimental values were compared with the predicted values to check the adequacy of the model. Ultrasound extraction was 33.60% higher than maceration technique. This study indicated that UAE should contribute to a green process for valorization of peach palm by-products., Se aplicó la tecnología de extracción asistida por ultrasonido (EAU) para extraer los carotenoides totales procedentes del epicarpio seco de frutos de chontaduro utilizando aceite de soya como solvente de extracción. La optimización de los parámetros de extracción total de carotenoides a partir del epicarpio de chontaduro se realizó mediante la metodología de superficie de respuesta (RSM) y el diseño central compuesto (CCD). Los parámetros de extracción fueron la temperatura, el tiempo de extracción y la relación sólido-solvente. Las condiciones óptimas de la extracción asistida por EAU fueron: 48 ° C, tiempo de extracción de 28 min, y relación de sólido-solvente de 0.0037 g/mL, con un contenido de carotenoides predicho de 151.50 mg/100 g de epicarpio seco. Para validar el modelo optimizado, los valores experimentales se compararon con los valores predichos para verificar la adecuación y el ajuste del modelo. La extracción mediante ultrasonido fue 33.60% más alta que la técnica de maceración, razón por la cual este estudio indicó que la EAU representa una contribución ecológica en la valorización de subproductos procedentes de frutos de chontaduro.

The main objective of this work is to comprehensively investigate R450A behavior in refrigeration systems and subsequently optimize the main operating variables for the first time to reach the maximum performance. For this purpose, a hybrid multi-objective optimization model coupling response surface method and non-dominated sorted genetic algorithm II is established. The regression analysis results reveal a good agreement of experimental data samples with the quadratic polynomial models with a coefficient of determination exceeding 0.97. The optimum results for the first scenario indicate that the reduction in the motor-compressor electrical power consumption and discharge temperature is 18.39% and 53.51%, respectively, and percentage of growth in the refrigerant mass flow rate is 215.57% when the middle evaporator temperature, middle condenser temperature, superheating degree, and subcooling degree change from −14.95 °C to 8.71°C, 31.28 °C to 24.50°C, 13.12 K to 10.49 K, and 15.65 K to 15.66 K, respectively., QC 20190319

Selenium nanoparticles (SeNPs) are successfully synthesized through microwave heating by using Theobroma cacao L. bean shell extract as a stabilizing and capping agent. Response surface methodology is used to obtain optimal synthesis conditions. The effect of microwave power, irradiation time and amount of Na2SeO3 are evaluated on crystalline size by X-Ray Diffraction (XRD) and Z-potential by Dynamic Light Scattering (DLS) using a central composite design (CCD). Optimal synthesis conditions are determined as 15.6 min, 788.6 W and 0.14 g of sodium selenite using 50 mL of Theobroma cacao L. bean shell extract. The successful biosynthesis of SeNPs is confirmed by UV-visible and Fourier Transformed Infrared (FTIR) spectroscopic analyses. The XRD pattern and Raman spectra show the presence of trigonal and amorphous synthesized SeNPs. Spherical SeNPs are observed by Transmission Electron Microscopy (TEM) with a particle size of 1–3 nm in diameter, at least one order of magnitude lower than those previously reported. The obtained SeNPs can be stable up to 55 days at 4 °C. Additionally, the SeNPs show an excellent antioxidant performance by the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and ferric reducing antioxidant power (FRAP) methods, with potential application in different sectors, such as food, medical and pharmaceutical.

The aim of study was to model and optimize the extraction of polyphenols and flavonoids with expressed antioxidant activity from chickpea seeds using a central composite design. The optimal extraction conditions were the extraction time of 145.5 min, ethanol concentration of 83.7% and liquid-to-solid ratio of 24.9 (expressed as cm(3) per g). The content of total polyphenol and flavonoid was 2.75 g gallic acid equivalent per kilogram of the dried extract and 0.147 g rutin equivalent per kilogram of the dried extract, respectively. Using 2,2-diphenyl-1-picrylhydrazyl assay, it was found that the optimal extract had the IC50 of 1.55 mg cm(-3).

Background: Citric acid, aside its uses as a cleaning agent, has varied applications in the chemical, pharmaceutical, and food industries. A biotechnological fermentation process is one of the easiest ways to satisfy the demands for this useful commodity. Methods: The fermentation of pineapple waste by Aspergillus niger for the production of citric acid was investigated in this study. STATISTICA 8 release 7 (Statsoft, Inc. USA) statistical software was used for the design of experiments, evaluation, and optimization of the process using the central composite design (CCD), a response surface methodology approach. Lower-upper limits of the design for the operating parameters were temperature (25-35 oC), fermentation time (35-96 h), pH (3-6), methanol concentration (1-7%) and glucose (15-85 g/L). Twenty-seven duplicated experimental runs were generated for the CCD route. Results & Conclusion: The optimal operating conditions were validated at 38 g/L of glucose concentration, 3% (v/v) of methanol, 50 h of fermentation time, pH of 4.3 and temperature of 30 oC which yielded15.51 g/L citric acid. The statistical significance of the model was evaluated using a one-way analysis of variance. The validated predicted response values obtained from the statistical model showed close relationships with the experimental data

Background: Citric acid, aside its uses as a cleaning agent, has varied applications in the chemical, pharmaceutical, and food industries. A biotechnological fermentation process is one of the easiest ways to satisfy the demands for this useful commodity. Methods: The fermentation of pineapple waste by Aspergillus niger for the production of citric acid was investigated in this study. STATISTICA 8 release 7 (Statsoft, Inc. USA) statistical software was used for the design of experiments, evaluation, and optimization of the process using the central composite design (CCD), a response surface methodology approach. Lower-upper limits of the design for the operating parameters were temperature (25-35 oC), fermentation time (35-96 h), pH (3-6), methanol concentration (1-7%) and glucose (15-85 g/L). Twenty-seven duplicated experimental runs were generated for the CCD route. Results & Conclusion: The optimal operating conditions were validated at 38 g/L of glucose concentration, 3% (v/v) of methanol, 50 h of fermentation time, pH of 4.3 and temperature of 30 oC which yielded15.51 g/L citric acid. The statistical significance of the model was evaluated using a one-way analysis of variance. The validated predicted response values obtained from the statistical model showed close relationships with the experimental data

Selenium nanoparticles (SeNPs) are successfully synthesized through microwave heating by using Theobroma cacao L. bean shell extract as a stabilizing and capping agent. Response surface methodology is used to obtain optimal synthesis conditions. The effect of microwave power, irradiation time and amount of Na2SeO3 are evaluated on crystalline size by X-Ray Diffraction (XRD) and Z-potential by Dynamic Light Scattering (DLS) using a central composite design (CCD). Optimal synthesis conditions are determined as 15.6 min, 788.6 W and 0.14 g of sodium selenite using 50 mL of Theobroma cacao L. bean shell extract. The successful biosynthesis of SeNPs is confirmed by UV-visible and Fourier Transformed Infrared (FTIR) spectroscopic analyses. The XRD pattern and Raman spectra show the presence of trigonal and amorphous synthesized SeNPs. Spherical SeNPs are observed by Transmission Electron Microscopy (TEM) with a particle size of 1–3 nm in diameter, at least one order of magnitude lower than those previously reported. The obtained SeNPs can be stable up to 55 days at 4 °C. Additionally, the SeNPs show an excellent antioxidant performance by the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and ferric reducing antioxidant power (FRAP) methods, with potential application in different sectors, such as food, medical and pharmaceutical.

The optimal conditions for the reduction of COD and NH3-N using cockle shells (CS) from a stabilised landfill effluent were analyzed. The influence of two variables (adsorbent dosage and pH) were analysed through the application of response surface methodology (RSM) and central composite design (CCD). Quadratic models were developed for the removals of COD and NH3-N parameters. The optimum conditions for removal of 65.6% and 53.6% for COD and NH3-N respectively was achieved at pH 6.34, adsorbent dosage of 20.21 g having 0.888 desirability value. The model F-value obtained for NH3-N removal Prob. > F value of 0.0001 with F-value of 104.21 was obtained. Similarly the Prob. > F value of < 0.0001 for COD with F-value of 82.74 was obtained, these P-values confirmed the significance of the model. The predicted response versus the experimental response depicted that the experimental data were relatively close to the predicted data. Thus, the generated models significantly enclosed the correlation between the process variables and the response.   GMT Detect languageAfrikaansAlbanianArabicArmenianAzerbaijaniBasqueBelarusianBengaliBosnianBulgarianCatalanCebuanoChichewaChinese (Simplified)Chinese (Traditional)CroatianCzechDanishDutchEnglishEsperantoEstonianFilipinoFinnishFrenchGalicianGeorgianGermanGreekGujaratiHaitian CreoleHausaHebrewHindiHmongHungarianIcelandicIgboIndonesianIrishItalianJapaneseJavaneseKannadaKazakhKhmerKoreanLaoLatinLatvianLithuanianMacedonianMalagasyMalayMalayalamMalteseMaoriMarathiMongolianMyanmar (Burmese)NepaliNorwegianPersianPolishPortuguesePunjabiRomanianRussianSerbianSesothoSinhalaSlovakSlovenianSomaliSpanishSundaneseSwahiliSwedishTajikTamilTeluguThaiTurkishUkrainianUrduUzbekVietnameseWelshYiddishYorubaZulu AfrikaansAlbanianArabicArmenianAzerbaijaniBasqueBelarusianBengaliBosnianBulgarianCatalanCebuanoChichewaChinese (Simplified)Chinese (Traditional)CroatianCzechDanishDutchEnglishEsperantoEstonianFilipinoFinnishFrenchGalicianGeorgianGerm

This study deals with isolation and optimization of soil origin fungus Drechslera sp. with valued unsaturated fatty acids using orange peel as a substrate. Accordingly, to maximize oil production, various parameters were optimized using 'one variable at a time' strategy followed by employing statistical designs (Plackett-Burman (PBD) & Response surface methodology (RSM)). The results showed that incubation time, FeSO4, pH and yeast extract were the most significant factors influencing lipid accumulation. Therefore, RSM employed to optimize their concentrations. The optimum parameter values were:  incubation time 144 h, FeSO4 0.015 g/L, pH 8.5 and yeast extract 2 g/L. Under the optimized conditions, a total biomass of 12 g/L with a lipid content of 40.75 % (corresponding to a lipid yield of 4.89 g/L) was achieved. The fatty acid profile revealed production of 41.99 % of unsaturated fatty acids. The feasibility of utilizing orange peel as a sole carbon source proved that it represents a potentially valuable source of single cell oil (SCO) with oil yield of 3.65 g/L. Its FAME profile revealed an increment of unsaturated fatty acids up to 58.86% with desirable amounts of polyunsaturated fatty acids (PUFA) 33.31 %, this making it as ideal substrate for production of unsaturated fatty acids.

This study deals with isolation and optimization of soil origin fungus Drechslera sp. with valued unsaturated fatty acids using orange peel as a substrate. Accordingly, to maximize oil production, various parameters were optimized using 'one variable at a time' strategy followed by employing statistical designs (Plackett-Burman (PBD) & Response surface methodology (RSM)). The results showed that incubation time, FeSO4, pH and yeast extract were the most significant factors influencing lipid accumulation. Therefore, RSM employed to optimize their concentrations. The optimum parameter values were:  incubation time 144 h, FeSO4 0.015 g/L, pH 8.5 and yeast extract 2 g/L. Under the optimized conditions, a total biomass of 12 g/L with a lipid content of 40.75 % (corresponding to a lipid yield of 4.89 g/L) was achieved. The fatty acid profile revealed production of 41.99 % of unsaturated fatty acids. The feasibility of utilizing orange peel as a sole carbon source proved that it represents a potentially valuable source of single cell oil (SCO) with oil yield of 3.65 g/L. Its FAME profile revealed an increment of unsaturated fatty acids up to 58.86% with desirable amounts of polyunsaturated fatty acids (PUFA) 33.31 %, this making it as ideal substrate for production of unsaturated fatty acids.

Central composite experimental design was used for fast, simple, and accurate high-performance liquid chromatography (HPLC) determination of hydrochlorothiazide, amlodipine and valsartan in combined dosage forms. This method avoids the disadvantages of the traditional analytical approach, which is time-consuming, involves a large number of runs, and does not allow establishing the multiple interacting parameters. On the basis of preliminary experiments and physicochemical characteristic of analyzed substances, three independent variables (methanol content, pH of the mobile phase, and column temperature) were selected as input, while as dependent variables, six responses (retention time of hydrochlorothiazide, retention time of amlodipine, retention time of valsartan, asymmetry of hydrochlorothiazide peak, asymmetry of amlodipine peak, and asymmetry of valsartan peak) were chosen. Face centered central composite design enables an estimation of factors which have the most importance. After optimizing experimental conditions, a separation was conducted on a Zorbax C-8 (150 mm x 4.6 mm, 5 mu m) column with a mobile phase consisting of methanol-acetonitrile-acetate buffer 40: 20: 40 (v/v/v), pH adjusted to 3.5 with acetic acid, flow rate of 1 mL/min and column temperature of 40 C-deg. The method was successfully applied to the simultaneous separations of these active drug compounds in their commercial dosage forms.

type:Journal Article, Aims: Statistical approach, central composite design (CCD) was used to investigate the complex interaction among temperature (25-37℃), initial medium pH (5-9), inoculum size (4-10 % (v/v)), concentration of (NH4)2SO4 (0-1 g/L) and concentration of mixed organic acids (5-10 g/L) in the production of polyhydroxyalkanoates by Comamonas sp. EB172., Methodology and Results: Mixed organic acids derived from anaerobically treated palm oil mill effluent (POME) containing acetic:propionic:butyric (ratio of 3:1:1) were used as carbon source in the batch culture of Comamonas sp. EB172 to produce polyhydoxyalkanoates (PHAs). The analysis of variance (ANOVA) showed that all five factors were significantly important in the batch fermentation by shake flask with a P value of less than 0.001. The optimal temperature, initial medium pH, inoculum size, concentration of (NH4)2SO4 and concentration of mixed organic acids were 30℃, 7.04, 4.0 % (v/v), 0.01 g/L and 5.05 g/L respectively., Conclusion, significance and impact of study: Optimization of the production medium containing mixed organic acids has improved the PHA production for more than 2 folds. Under optimal condition in the shake flask fermentation, the predicted growth is 2.98 g/L of dry cell weight (DCW) with 47.07 wt % of PHA content. The highest yield of PHA was 0.28 g of PHA per g mixed organic acids.

This study presents a global sizing design optimisation of a permanent magnet synchronous generator (PMSG) using the three-dimensional finite-element analysis (3D FEA). To build an optimal parametric model structure, the efficiency improvement of the PMSG is taken as the main objective, where iron and copper losses were minimised. A dual-level response surface methodology (D-RSM) with a window-zoom-in approach for a variable-speed-range analysis as a global optimisation technique is employed to find out the optimal design variables of the objective function. The D-RSM using mixed-resolution central composite design (MR-CCD), full factorial design, central composite design (CCD), and box-Behnken design are applied to optimise the geometry with very small error. Analysis of variance and multi-level RSM plots are used to check the adequacy of fit. However, the MR-CCD exceeds the range of the boundary in the design region. Hence, a modified MR-CCD is used that improves the efficiency and proposes the parameter settings to manufacture the high-class quality wind generator. The validation of the analytical and numerical fashions is successfully achieved through rigorous FEA, and the experimental verifications perfectly marked the theoretical and significance optimisation design., Peer Reviewed, Postprint (author's final draft)

One of the major objectives of food industry is predicting the sensory profile of a product by chemical analysis. In the case of spirit drinks, their volatile compounds can exhibit odour interactive effects. This study investigated the odour perception of linalool, ethyl hexanoate, ethyl acetate and acetaldehyde with model solutions (in 40% v/v ethanol) on flowery, fruity and glue- like attributes. Design of experiments for sensory analysis and response surface methodology were used to evaluate the aroma interactions of these compounds by sniffing or orthonasal olfaction. Results showed that ethyl hexanoate masks flowery and glue-like descriptors. Acetaldehyde provides a low-intensity fruity odour, which is confused with ethyl hexanoate odour. High levels of ethyl acetate suppress and enhance the fruity descriptor at high and low levels of ethyl hexanoate, respectively. In sum- mary, this sensory technique enables the rapid but consistent assessment of the interaction of aroma compounds in an alcoholic spirit. It is s uggeste d that this approach may be a useful tool in the optimization and development of alcoholic products.

This paper applied the response surface methodology (RSM) to optimizing a novel Fe(II)/citrate/UV/PMS process in the degradation of a model micropollutant, carbamazepine (CBZ), a persistent emerging contaminant frequently detected in surface water and groundwater. The experimental conditions in terms of two responses, CBZ removal efficiency (Y1) and cost per unit CBZ removal (Y2), were optimized by the central composite design (CCD) in RSM. Modeling data exhibited that the optimum condition resulting in the lowest Y2 while achieving >70% of Y1 was at a UV dose of 265.5 mJ/cm2 and Fe(II), PMS and citrate concentrations of 12.2 μM, 100 μM and 26.4 μM, respectively. Increasing Fe(II) concentration led to the decrease in CBZ degradation and cost-effectiveness of the process. On the other hand, increasing the UV dose, PMS concentration and citrate/Fe(II) ratio over 265.5 mJ/cm2, 100 μM and 2.16:1, respectively, slightly increased the CBZ degradation, but significantly increased the cost. Under the optimized condition, the experimentally obtained values for Y1 and Y2 were 70.44% and 0.0104 H K$/%/m3, respectively. The predicted Y1 and Y2 were 71.07% and 0.0098 H K$/%/m3, respectively, suggesting that RSM can be readily used to determine the optimum condition of the Fe(II)/citrate/UV/PMS process for CBZ degradation. Other aqueous constituents which impacted the CBZ removal in the Fe(II)/citrate/UV/PMS process are in the following order: NOM > alkalinity > bromide > ammonia ≈ chloride (both negligible). © 2017 Elsevier Ltd

The Kenya’s vision 2030 seeks to address the rising needs of its population through infrastructure development. Reinforced concrete being the most commonly used construction material forms an integral part of this development strategy. The direct substitution of the ordinary Portland cements with the cheaper, lower strength, locally available blended Portland cements could be responsible for the production of poor quality concrete and contribute to the failure of several concrete buildings in the country. This paper presents findings of an experimental investigation on the appropriate mix proportions for the Kenyan blended Portland cement concrete. Key variables used in this study included the water/ cement ratio (x1), the cement/ total aggregates ratio (x2) and the fine aggregates/ coarse aggregates ratio (x3). The response was measured in terms of slump, compressive strengths at 7days, 14days and 28 days and density. Minitab 17 software was used in the design of experiments and results analysis based on Central Composite Design method. The investigation revealed that for a workable concrete with slump of ≥ 30mm, the appropriate mix ratios for the Kenyan blended Portland cement concrete are: 1:2.2:3.4 (w/c 0.6) for strength class C15 and 1:1.3:2.2 (w/c 0.5) for strength class C20. It was further noted that the different brands of blended Portland cement in the country had varying properties and thus produced concrete with different wet and hardened properties. None of the brands achieved the target design strength for strength class C25 and above. Therefore, the blended Portland cements may not be suitable for producing structural concrete strength class C 25 and above.

The Kenya’s vision 2030 seeks to address the rising needs of its population through infrastructure development. Reinforced concrete being the most commonly used construction material forms an integral part of this development strategy. The direct substitution of the ordinary Portland cements with the cheaper, lower strength, locally available blended Portland cements could be responsible for the production of poor quality concrete and contribute to the failure of several concrete buildings in the country. This paper presents findings of an experimental investigation on the appropriate mix proportions for the Kenyan blended Portland cement concrete. Key variables used in this study included the water/ cement ratio (x1), the cement/ total aggregates ratio (x2) and the fine aggregates/ coarse aggregates ratio (x3). The response was measured in terms of slump, compressive strengths at 7days, 14days and 28 days and density. Minitab 17 software was used in the design of experiments and results analysis based on Central Composite Design method. The investigation revealed that for a workable concrete with slump of ? 30mm, the appropriate mix ratios for the Kenyan blended Portland cement concrete are: 1:2.2:3.4 (w/c 0.6) for strength class C15 and 1:1.3:2.2 (w/c 0.5) for strength class C20. It was further noted that the different brands of blended Portland cement in the country had varying properties and thus produced concrete with different wet and hardened properties. None of the brands achieved the target design strength for strength class C25 and above. Therefore, the blended Portland cements may not be suitable for producing structural concrete strength class C 25 and above.

The Kenya’s vision 2030 seeks to address the rising needs of its population through infrastructure development. Reinforced concrete being the most commonly used construction material forms an integral part of this development strategy. The direct substitution of the ordinary Portland cements with the cheaper, lower strength, locally available blended Portland cements could be responsible for the production of poor quality concrete and contribute to the failure of several concrete buildings in the country. This paper presents findings of an experimental investigation on the appropriate mix proportions for the Kenyan blended Portland cement concrete. Key variables used in this study included the water/ cement ratio (x1), the cement/ total aggregates ratio (x2) and the fine aggregates/ coarse aggregates ratio (x3). The response was measured in terms of slump, compressive strengths at 7days, 14days and 28 days and density. Minitab 17 software was used in the design of experiments and results analysis based on Central Composite Design method. The investigation revealed that for a workable concrete with slump of ? 30mm, the appropriate mix ratios for the Kenyan blended Portland cement concrete are: 1:2.2:3.4 (w/c 0.6) for strength class C15 and 1:1.3:2.2 (w/c 0.5) for strength class C20. It was further noted that the different brands of blended Portland cement in the country had varying properties and thus produced concrete with different wet and hardened properties. None of the brands achieved the target design strength for strength class C25 and above. Therefore, the blended Portland cements may not be suitable for producing structural concrete strength class C 25 and above.

The Kenya’s vision 2030 seeks to address the rising needs of its population through infrastructure development. Reinforced concrete being the most commonly used construction material forms an integral part of this development strategy. The direct substitution of the ordinary Portland cements with the cheaper, lower strength, locally available blended Portland cements could be responsible for the production of poor quality concrete and contribute to the failure of several concrete buildings in the country. This paper presents findings of an experimental investigation on the appropriate mix proportions for the Kenyan blended Portland cement concrete. Key variables used in this study included the water/ cement ratio (x1), the cement/ total aggregates ratio (x2) and the fine aggregates/ coarse aggregates ratio (x3). The response was measured in terms of slump, compressive strengths at 7days, 14days and 28 days and density. Minitab 17 software was used in the design of experiments and results analysis based on Central Composite Design method. The investigation revealed that for a workable concrete with slump of ? 30mm, the appropriate mix ratios for the Kenyan blended Portland cement concrete are: 1:2.2:3.4 (w/c 0.6) for strength class C15 and 1:1.3:2.2 (w/c 0.5) for strength class C20. It was further noted that the different brands of blended Portland cement in the country had varying properties and thus produced concrete with different wet and hardened properties. None of the brands achieved the target design strength for strength class C25 and above. Therefore, the blended Portland cements may not be suitable for producing structural concrete strength class C 25 and above.

The Kenya’s vision 2030 seeks to address the rising needs of its population through infrastructure development. Reinforced concrete being the most commonly used construction material forms an integral part of this development strategy. The direct substitution of the ordinary Portland cements with the cheaper, lower strength, locally available blended Portland cements could be responsible for the production of poor quality concrete and contribute to the failure of several concrete buildings in the country. This paper presents findings of an experimental investigation on the appropriate mix proportions for the Kenyan blended Portland cement concrete. Key variables used in this study included the water/ cement ratio (x1), the cement/ total aggregates ratio (x2) and the fine aggregates/ coarse aggregates ratio (x3). The response was measured in terms of slump, compressive strengths at 7days, 14days and 28 days and density. Minitab 17 software was used in the design of experiments and results analysis based on Central Composite Design method. The investigation revealed that for a workable concrete with slump of ? 30mm, the appropriate mix ratios for the Kenyan blended Portland cement concrete are: 1:2.2:3.4 (w/c 0.6) for strength class C15 and 1:1.3:2.2 (w/c 0.5) for strength class C20. It was further noted that the different brands of blended Portland cement in the country had varying properties and thus produced concrete with different wet and hardened properties. None of the brands achieved the target design strength for strength class C25 and above. Therefore, the blended Portland cements may not be suitable for producing structural concrete strength class C 25 and above.

Millions of off-grid homes in remote areas around the world have access to pico-hydro (5kW or less) resources that are undeveloped due to prohibitive installed costs ($/kW). The Turgo turbine, a hydroelectric impulse turbine generally suited for medium to high head applications, has gained renewed attention in research due to its potential applicability to such sites. Nevertheless, published literature about the Turgo turbine is limited and indicates that current theory and experimental knowledge do not adequately explain the effects of certain design parameters, such as nozzle diameter, jet inlet angle, number of blades, and blade speed on the turbine's efficiency. In this study, these parameters are used in a three-level (34) central composite response surface experiment. A low-cost Turgo turbine is built and tested from readily available materials and a second order regression model is developed to predict its efficiency as a function of each parameter above and their interactions. The effects of blade orientation angle and jet impact location on efficiency are also investigated and experimentally found to be of relatively little significance to the turbine. The purpose of this study is to establish empirical design guidelines that enable small hydroelectric manufacturers and individuals to design low-cost efficient Turgo Turbines that can be optimized to a specific pico-hydro site. The results are also expressed in dimensionless parameters to allow for potential scaling to larger systems and manufacturers.

20(S)-Protopanaxadiol (PPD), a bioactive compound extracted from ginseng, possesse cardioprotective, neuroprotective, anti-inflammatory, antiestrogenic, anticancer and anxiolytic effects However, the clinical application of PPD is limited by its weak aqueous solubility. In this study we optimized an efficient method of preparing its phospholipid complex (PPD-PLC) using central composite design and response surface analysis. The prepared PPD-PLC was characterize by differential scanning calorimetric, powder X-ray diffraction, Fourier-Transformed infrare spectroscopy and nuclear magnetic resonance analyses associated with molecular docking calculation The equilibrium solubility of PPD-PLC in water and n-octanol increased 6.53-and 1.53-Times respectively. Afterwards, using PPD-PLC as the intermediate, the PPD-PLC-loaded dry suspensio (PPD-PLC-SU) was prepared with our previous method. In vitro evaluations were conducted o PPD-PLC and PPD-PLC-SU, including dissolution behaviors and stability properties under differen conditions. Results of in vitro dissolution behavior revealed the improved dissolution extents an rates of PPD-PLC and PPD-PLC-SU (p < 0.05). Results of the formulation stability investigatio also exposed the better stability of PPD-PLC-SU compared with free PPD. Therefore, phospholipi complex technology is a useful formulation strategy for BCS II drugs, as it could effectively improv their hydrophilicity and lipophilicity.

Statistically designed experiments were proceeded to evaluate nutritional and environmental parameters that affect nitrate reductase enzyme (NR) activity in Achromobacter sp. KT735046. Plackett-Burman design was performed for screening and identifying efficiently the significance of 15 culture conditions influencing NR activity. FeCl3 ·6H2O, Na2MoO4 ·2H2O and CuSO4.5H2O were the most significant variables positively influencing, whereas pH was the most significant negative contributors. The optimal levels of significant factors were further predicted from five level factorial designs, Central Composite Design (CCD). The optimum parameter values were CuSO4.5H2O (60.375) mg/l, FeCl3·6H2O (240 mg /L), pH (6.135) and Na2MoO4·2H2O (150 mg /L). The biogenic Iron oxide nanoparticles "IONPs" were characterized; the dark brown IONPs exhibit maximum absorption from 400 to 464 nm, XRD reveals crystallite rhombohedral hematite, EDX confirms presence of 62% of iron, TEM illustrates formation of tiny IONPs, 1.4 and 2.8 nm in size, ξ potential and PDI recorded -42.9 mV and 0.268 respectively exhibiting high stability and monodispersed with no agglomeration by the help of biomolecules. This study conclude that Achromobacter sp. KT735046 consider being biofactory for synthesis nanoparticles by the help of NR enzyme and it may be the first time to optimize Achromobacter sp. KT735046 for IONPs biosynthesis using statistical designs.&nbsp

Statistically designed experiments were proceeded to evaluate nutritional and environmental parameters that affect nitrate reductase enzyme (NR) activity in Achromobacter sp. KT735046. Plackett-Burman design was performed for screening and identifying efficiently the significance of 15 culture conditions influencing NR activity. FeCl3 ·6H2O, Na2MoO4 ·2H2O and CuSO4.5H2O were the most significant variables positively influencing, whereas pH was the most significant negative contributors. The optimal levels of significant factors were further predicted from five level factorial designs, Central Composite Design (CCD). The optimum parameter values were CuSO4.5H2O (60.375) mg/l, FeCl3·6H2O (240 mg /L), pH (6.135) and Na2MoO4·2H2O (150 mg /L). The biogenic Iron oxide nanoparticles "IONPs" were characterized; the dark brown IONPs exhibit maximum absorption from 400 to 464 nm, XRD reveals crystallite rhombohedral hematite, EDX confirms presence of 62% of iron, TEM illustrates formation of tiny IONPs, 1.4 and 2.8 nm in size, ξ potential and PDI recorded -42.9 mV and 0.268 respectively exhibiting high stability and monodispersed with no agglomeration by the help of biomolecules. This study conclude that Achromobacter sp. KT735046 consider being biofactory for synthesis nanoparticles by the help of NR enzyme and it may be the first time to optimize Achromobacter sp. KT735046 for IONPs biosynthesis using statistical designs.&nbsp

20(S)-Protopanaxadiol (PPD), a bioactive compound extracted from ginseng, possesse cardioprotective, neuroprotective, anti-inflammatory, antiestrogenic, anticancer and anxiolytic effects However, the clinical application of PPD is limited by its weak aqueous solubility. In this study we optimized an efficient method of preparing its phospholipid complex (PPD-PLC) using central composite design and response surface analysis. The prepared PPD-PLC was characterize by differential scanning calorimetric, powder X-ray diffraction, Fourier-Transformed infrare spectroscopy and nuclear magnetic resonance analyses associated with molecular docking calculation The equilibrium solubility of PPD-PLC in water and n-octanol increased 6.53-and 1.53-Times respectively. Afterwards, using PPD-PLC as the intermediate, the PPD-PLC-loaded dry suspensio (PPD-PLC-SU) was prepared with our previous method. In vitro evaluations were conducted o PPD-PLC and PPD-PLC-SU, including dissolution behaviors and stability properties under differen conditions. Results of in vitro dissolution behavior revealed the improved dissolution extents an rates of PPD-PLC and PPD-PLC-SU (p < 0.05). Results of the formulation stability investigatio also exposed the better stability of PPD-PLC-SU compared with free PPD. Therefore, phospholipi complex technology is a useful formulation strategy for BCS II drugs, as it could effectively improv their hydrophilicity and lipophilicity.