Qualitek-4 Software Research Articles

Functional parametric influence on glutaminase free l-asparaginase production by Amycolatopsis thermoflava SFMA-103

l-Asparaginase (l-ASNase) is a well known chemotherapeutic enzyme, to treat different neoplasms, especially in treating Acute Lymphoblastic Leukaemia (ALL) of children and adults. However, production of glutaminase free l-ASNase is the central area of research to produce cytotoxicity free L-ASNases in the cancer therapeutics. The present study explored the potential glutaminase free l-ASNase production from rare actinobacterium, Amycolatopsis thermoflava SFMA-103 isolated from agricultural field soils. The attention of the enzyme production was sequentially optimized using various methods starting from One-factor-at-a-time (OFAT) to Taguchi orthogonal array (OA) experimental design (DOE). Four critical factors, pH, temperature, arabinose and yeast extract were identified initially, hence, three levels with a layout of L9 (34) were used and further processed with Qualitek-4 software. Upon validation an enhanced enzyme production of 68.55% was observed (from 10 IU −1 min−1 to 31.8 IU −1 min−1). As far as our knowledge extends, glutaminase-free l-ASNase production is the first time report from Amycolatopsis thermoflava SFMA-103. Further, scale-up studies were performed using bench scale bioreactor (5L capacity) with the statistically optimized conditions (aeration of 0.5 VVM and agitation of 150 rpm at 40 °C) resulted in an improved enzyme production to the level of 132.69% (61.6 IU −1 min−1) with an incubation period of 66 h. Taguchi methods for scale-up studies of l-ASNase proves useful in bioprocess optimization with minor experimental set up, saving cost and time consumption is low.

Analisis Pengendalian Kualitas Produk Mengunakan Metode Taguchi dan FMEA di PT Raharjo Perkasa Multikarya

PT Raharjo Perkasa Multikarya was first established in 2015, under the name PT. Multipurpose Continent or Concrete Continent. Based on the results of observations, it was found that the quality of management of the company was found to be a factor of disability originating from delays in arriving raw materials, operator errors and untimely mixing. It is known from calculations using the FuzzyFMEA method with FRPN values. As for the existing failures, it occurred in Rank 1 of 72900 with failures occurring due to operator error, Rank 2 of 57600 with failures occurring because the mixing process was not carried out on time, and Rank 3 of 51200 with failures occurring due to delays in the arrival of raw materials. Calculations in the second study were carried out using the Taguchi method from values ​​calculated with the help of Qualitek-4 and FMEA software. The research objective was carried out to optimize product quality, and also to provide input for improvement in the cast concrete mix process. Based on the results of the FRPN the following are (Rank 1), namely the results obtained on the identification of the risk of failure carried out by operator error, namely 72900. And based on calculations using the Taguchi method of cast concrete mix, namely with a guide weight of sand 980 (kg), weight of cement 30 (kg), stirring time 450 (seconds), volume in water 40 (liters) and gravel weight 5 (kg). With the aim to minimize the category of defects. In other words, the determination of the desired quality characteristics in the cast concrete mix the lower the number of defects categories produced in the production process, the less so that customer demands can be fulfilled.

Analisis Pengendalian Kualitas Produk Mengunakan Metode Taguchi dan FMEA di PT Raharjo Perkasa Multikarya

PT Raharjo Perkasa Multikarya was first established in 2015, under the name PT. Multipurpose Continent or Concrete Continent. Based on the results of observations, it was found that the quality of management of the company was found to be a factor of disability originating from delays in arriving raw materials, operator errors and untimely mixing. It is known from calculations using the FuzzyFMEA method with FRPN values. As for the existing failures, it occurred in Rank 1 of 72900 with failures occurring due to operator error, Rank 2 of 57600 with failures occurring because the mixing process was not carried out on time, and Rank 3 of 51200 with failures occurring due to delays in the arrival of raw materials. Calculations in the second study were carried out using the Taguchi method from values ​​calculated with the help of Qualitek-4 and FMEA software. The research objective was carried out to optimize product quality, and also to provide input for improvement in the cast concrete mix process. Based on the results of the FRPN the following are (Rank 1), namely the results obtained on the identification of the risk of failure carried out by operator error, namely 72900. And based on calculations using the Taguchi method of cast concrete mix, namely with a guide weight of sand 980 (kg), weight of cement 30 (kg), stirring time 450 (seconds), volume in water 40 (liters) and gravel weight 5 (kg). With the aim to minimize the category of defects. In other words, the determination of the desired quality characteristics in the cast concrete mix the lower the number of defects categories produced in the production process, the less so that customer demands can be fulfilled.

Cross-linking of polyvinyl alcohol-g-methionine with bisacrylamide and optimization of its swelling response using taguchi method

A hydrophilic macromolecular network is synthesized by crosslinking of grafted polyvinyl alcohol methionine with bisacrylamide (PVAMB). Firstly, polyvinyl alcohol (PVA) was chemically modified by grafting methionine onto its backbone using persulphate initiator. Secondly, the crosslinking of grafted polymer was carried out using N, N’ - Methylene bisacrylamide. The crosslinked macromolecule was characterized by UV Visible spectroscopy, FTIR spectroscopy, X-ray diffraction. The thermal behaviour of the crosslinked polymer was analysed using thermogravimetric analyser. The thermal stability of the polymeric network was found to be stable up to 400 °C. To optimize the performance and quality of the synthesized cross-linked polymer, Taguchi L-9 orthogonal array of experiments were designed with the factors such as weight of the hydrogel, pH, time of exposure and temperature using Qualitek-4 software. The studies revealed that PVAMB retains water molecules in their network to a greater extent in neutral solution. Also the swelling behaviour of the cross-linked polymer was investigated in various physiological solutions.

Experimental and statistical analysis of CO2 absorption in DEA/water nanofluid containing silicon dioxide nanoparticle

In this investigation, the equilibrium absorption of CO2 in diethanolamine (DEA)/water solutions has been measured in the presence and absence of SiO2 nanoparticles using the isochoric saturation method. Experiments have been performed at the temperature range of 276.1–333.1 K, initial pressure range of 4–15 bars, DEA concentrations of 10, 15, 20, and 25 wt.%, and nanoparticle concentrations of 0.5, 1.0, and 1.5 wt.%. To understand the effect of operating variables with fewer number of experiments, design of experiment has been performed using Qualitek-4 software and Taguchi algorithm. Totally, 16 experiments were suggested. According to the results, increasing the initial pressure and DEA concentration improved the solubility of CO2 in the solvent. The optimum concentration of SiO2 nanoparticle was 0.5 wt.%. More increase in nanoparticle concentration deteriorates the solubility of CO2 in the solvent.

Statistical design for biogenesis of melanin nanoparticles from producer strain Pseudomonas stutzeri BTCZ 109 through Taguchi DOE

Melanins are a group of biological macromolecules synthesized by a wide spectrum of living organisms mainly through oxidative polymerization of indolic and phenolic compounds. Because of its various properties including antioxidation, antibiofilm, metal chelation, UV protection and anticancer activity it has widespread application in agriculture, cosmetic and therapeutic industries which makes it commercially valuable and its large-scale production attain enormous consideration. The phylogenetic analysis reveals that the organism belongs to Pseudomonas stutzeri strain (BTCZ 109). Taguchi method of design of experiment (DOE) using Qualitek-4 software for the optimization of parameters to enhance melanin production was carried out in this study. L8 (27) type of Orthogonal Arrays (OA) was constructed using 7 variables including incubation time (days), inoculum concentration (%), pH, MgSO4.5H2O (mM), l-tyrosine (g/l), temperature (0C) and agitation (rpm). Maximum melanin production through different combinations of experimental variables, factors contributing to production and interaction among the selected factors at their given levels, were elucidated. 8 trials of experiments were performed under the L-8 Orthogonal Array (OA) designed by the Taguchi approach. The experimental data were analyzed using the Signal-to-noise (S/N) ratio with the ‘bigger is better’ characteristics to identify the influential parameters and to establish the optimum conditions for maximizing melanin production. Validation of the predicted data with the confirmatory experiments revealed a nominal value of 1328.855 μg/mL, with an average performance of 1158.27 μg/mL, at the optimized condition of incubation time 4 days, pH 8, temperature 35 °C, agitation 140 rpm, and MgSO4.5H2O (mM) 0.25 mM absorbance units (AU) of OD400. The melanin thus obtained was found to be nano-sized and which reveals its pharmaceutical, biomedical and environmental application.

Optimization of process parameters for biodegradation of malathion by Micrococcus aloeverae MAGK3 using Taguchi methodology and metabolic pathway analysis

In this study, a previously isolated bacterial strain, Micrococcus sp. MAGK3 was employed to explore its malathion biodegradation potential. A considerable degradation (66.79%) was attained with malathion (0.03%) being the sole carbon source after 240 h of incubation. To enhance malathion biodegradation, effects of co-substrates, pH, temperature, initial malathion concentration, agitation (rpm), and inoculum size were evaluated using Taguchi methodology. Experiments with various combinations of factors were conducted, and results in respect of malathion biodegradation were evaluated in the Qualitek-4 software to determine the key effect of individual factors, their interaction effects, and optimal levels of process factors. All parameters contributed to malathion biodegradation, and Taguchi DOE's ability to predict optimum response, was established by experimentation via optimized levels of factors (carbon source 0.1%, nitrogen source 0.1%, pH 7, temperature 35 °C, pesticide concentration 0.03%, agitation 150 rpm, and inoculum size 2%(w/v). Results confirmed that pesticide concentration caused the maximum impact (34.09%) on malathion degradation followed by nitrogen source (32.11%), temperature (20.99%), RPM (6.55%), inoculum size (3.26%), carbon source (2.81%) and pH (0.2%). Before optimization, Micrococcus sp. MAGK3 had an average degradation of 57.94% within 168 h, but after optimization, the rate of biodegradation improved to 87% within 38 h. Confirmation of malathion biodegradation was performed by UHPLC, and GC-MS analysis and a possible degradation pathway was proposed for malathion biodegradation by Micrococcus sp. MAGK3. For the time being, this is the first publication to employ the Taguchi design of experiment to optimize the degradation of malathion by Micrococcus sp. MAGK3.

Evaluation of Natural and Chemical Coagulants Performance in Treatment of Municipal Wastewater of Behshahr City

Municipal wastewater is one of the largest volumes of wastewater which contains various organic compounds from proteins and fats to carbohydrates and nucleic acids. Municipal wastewater of Behshahr city (Mazandaran, Iran) was evaluated using aluminum sulfate and iron chloride as chemical coagulants and pectin and sodium alginate as natural ones. Biological oxygen demand was investigated at different temperatures and coagulant concentrations. The fraction of full factorial statistical method and Qualitek-4 software were applied for designing experiments and analyzing the results to determine the optimal conditions for achieving the highest reduction in wastewater organic load and biological oxygen demand. In the case of biological oxygen demand, the optimal condition was achieved at 25°C, using 1, 0.02, 1.5 and 1 g/L of aluminum sulfate, sodium alginate, iron chloride and pectin, respectively. Under the optimal condition, the percentage of biological oxygen demand reduction was equal to 34.5%. Maximum BOD removal of 40.9% was obtained at 25°C using aluminum sulfate, sodium alginate, iron chloride, and pectin at concentrations of 0.6, 0.02, 1.5, and 6 g/L, respectively. The contribution of aluminum sulfate, sodium alginate, iron chloride, and pectin concentration in biological oxygen demand removal of the studied wastewater was 3.8%, 22.4%, 16.3%, and 14.4%, respectively. Coagulation temperature and aluminum sulfate concentration with approximately 42.7% and 3.8% contribution values were determined as the most and the least effective factors in biological oxygen demand reduction.

Briquetting as a means of recovering energy from organic market waste

ABSTRACT Municipal Solid Waste is causing pollution and health hazards in cities around the world. In Kenya, existing and emerging cities are experiencing increased populations with increase in organic market waste. Organic market wastes can be used to produce briquettes. This study aimed to formulate available organic market waste into briquettes of optimal energy or calorific value. The study used locally fabricated technologies such as manual screw press, ram-piston and using bare human hands. Taguchi method was used based on controllable factors: Ratio of raw material; percentage (%) of binder; Size of raw material and method of production. Out of nine (9) experiments, laboratory results showed that the sixth (6th) and ninth (9th) formulations yielded briquettes with high calorific value of 20,540 kJ/kg and 18,962 kJ/kg, respectively. A further confirmatory experimental test was carried out based on Qualitek-4 software optimal simulated conditions. The test revealed that a mixture of carbonized market waste of particle size 2–5 mm; ratio of one part charcoal dust, two parts sawdust, and one part maize stover; with 30% of binder made using manual ram piston yielded briquettes of high calorific value of 21,633 kJ/kg against Qualitek-4 simulated value of 21,771 kJ/kg. In addition, Greenhouse gases evolved: CO and PM2.5 concentrations are within World Health Organization (WHO) and Kenya Subsidiary Legislation on critical limits allowable for human exposure. These indicates that organic market waste can be used to produce briquettes with acceptable quality using locally available technologies.

Evaluation of compressive and split tensile strength of slag based aluminosilicate geopolymer reinforced by waste polymeric materials using Taguchi method

In this work, slag based aluminosilicate geopolymer was reinforced with polymeric fibers including, polyester (PES) (waste tire cap plies), polymeric particles including polyethylene terephthalate (PET) (waste water bottle), styrene-butadiene rubber (SBR) (waste tire), and polyvinyl chloride (PVC) (waste water hose). The tensile and compressive strength of the material was evaluated. Taguchi method was employed to assess the influence of the effective parameters on the mechanical characteristics of the geopolymer composite. QUALITEK-4 software was used to create the L32 orthogonal array with 192(96+96) geopolymer specimens and 32+32 experiments. Analysis of variance (ANOVA) was utilized to analyze the results of the experiments. The prepared geopolymers were characterized by SEM analysis. The results revealed that the compressive and split tensile strength of the aluminosilicate geopolymer was substantially improved after reinforced by the PES fibers compared with other particles such as SBR, PVC, and PET.

Treatment of domestic wastewater using the combination of porous concrete and phytoremediation for irrigation

Phytoremediation method, in combination with porous concrete and some additives, has been examined in order to reduce the contamination of unconventional water resources. This treatment system is economically cost-effective and easy to apply, compared to other treatment methods. The current study was focused on evaluating the effects of arrangement of vetiver grass and porous concrete specimens (four types of grass-specimens arrangements), vetiver grass layout on polystyrene sheets (5 × 5 and 10 × 10 cm spacing), porous concrete mixture (basic design as control, basic design + 5% zeolite, basic design + 10% zeolite, basic design + 5% pumice), temperature of the test room (10 ± 2, 20 ± 2 and 30 ± 2 °C), type of the unconventional water (domestic wastewater effluent and urban runoff) and Portland cement type (2 and 5) on the reduction of biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), and fecal coliforms. Taguchi method (robust design) and Qualitek-4 software were used to optimize the combination of aforementioned factors. Results indicated that temperature was the most effective parameter on reducing the BOD, COD, and fecal coliforms. The vetiver grass layout on the polystyrene sheets and porous concrete mixture design were more effective than vetiver grass-porous concrete arrangement. Effect of vetiver grass roots was significant in reducing the TSS content. The cement type had minimum impact on reducing the qualitative parameters of the wastewater samples. Based on the results, combination of 10 × 10 cm spacing of vetiver grass on polystyrene sheets, third type of vetiver grass-porous concrete arrangement, porous concrete mixture with 10% zeolite, Portland cement Type 2, and room temperature of 30 ± 2 °C was the best for improving the quality of wastewater effluent as compared to urban runoff. The treated effluents can be used with caution for urban green spaces or irrigation purposes, and the difficulties of the proposed combined system should be taken into consideration.

4-Nitrophenol biodegradation by an isolated and characterized microbial consortium and statistical optimization of physicochemical parameters by Taguchi Methodology

A metabolically versatile and highly efficient 4-Nitrophenol degrading bacterial consortium was isolated from a pesticide-contaminated agricultural soil by successive enrichment on a mineral salt medium. Based on the phylogenetic analysis, the members of the consortium were found to be Brevibacterium sp. PNP1 (MH169212), Pseudomonas sp. PNP2 (MH169213), Agromyces mediolanus PNP3 (MH169214) and Microbacterium oxydans PNP4 (MH169215). Taguchi Design of experiments approach (DOE) was applied using Qualitek-4 software for the optimization of parameters to enhance the biomass growth and 4-Nitrophenol biodegradation efficiency. Nine physicochemical parameters such as magnesium sulphate, phosphate ion, yeast extract, calcium chloride, temperature, pH, inoculum dose, incubation time, and agitation speed were chosen for optimization due to their crucial impact on biomass growth and 4-Nitrophenol degradation. 27 trials of biodegradation experiments were performed under the L-27 Orthogonal Array (OA) designed by the Taguchi approach. The experimental data were analyzed using the Signal-to-noise (S/N) ratio with the 'bigger is better' characteristics to identify the influential parameters and to establish the optimum conditions for maximizing 4-Nitrophenol biodegradation. Validation of the predicted data with the confirmatory experiments revealed that 1.19 g/L of biomass and 99.12% of 4-Nitrophenol degradation could be attained resulting in 121.48% and 249.88% enhancement in the biomass growth and 4-Nitrophenol degradation respectively, at the optimized condition of yeast extract 2.0 g/L, pH 9.5, temperature 32 °C, incubation time 78 h, agitation 160 rpm, and inoculum dose 0.5 absorbance units (AU) of OD600.

Solubility of CO2 in Aqueous Solutions of Diethanolamine (DEA) and Choline Chloride

In this study, the solubility of CO2 in DEA in the presence and absence of choline chloride was reported at different temperatures of 276.15, 298.15, 313.15, and 333.15 K, and pressure range of 4-15 bar. The solubility of CO2 was evaluated using the pressure decay method in a batch isochoric stirred absorption cell. Also, the design of experiments performed with Qualitek-4 software using the Taguchi method. Henry’s law constants at three different temperatures were calculated from the correlation of solubility data. Results showed that increasing the initial pressure and DEA concentration and also decreasing the temperature, increases the solubility of CO2. Optimum operating conditions to maximize the amount of CO2 absorption including the temperature of 276.15 K (minimum level), the initial pressure of 15 bar (maximum level), the concentration of DEA of 40 wt.% (maximum level), and the concentration of choline chloride of 5 wt.% (middle level). Also, Qualitek-4 software predicted the amount of solubility at the optimum conditions which was 7.5% different from the measured value.

Impact of bioaugmentation of soil with n-hexadecane-degrading bacteria and phosphorus source on the rate of biodegradation in a soil-slurry system

<p>In recent years, n-hexadecane, a component of diesel petroleum hydrocarbons, is frequently detected as the contaminant in many soils and water resources. The main aims of this study were focused on the feasibility of using the biodegradation for the removal of n-hexadecane from the soil-slurry system, by assessing the effects of phosphorus sources on biodegradation rate and determining the optimal conditions of the process. This study was carried out using an experimental method at the laboratory scale. The Taguchi method was used to optimize variables and their levels using the Qualitek-4 (w32b) software. We investigated the effects of initial concentration of n-hexadecane as the sole source of carbon (1-80 g/kg of soil), the role of phosphorus sources, at the concentration ranges from 10 to 600 g per Kg of soil, released by different bacterial species (Acinetobacter radioresistens, Pseudomonas aeruginosa, Bacillus subtilis, and the bacterial consortium) at the incubation time between 0 and 30 days. The optimum values of the response variables were predicted through signal-to-noise ratio (S/N). Results indicated that Bacillus subtilis were more effective in n-hexadecane degradation compared to the others (42%). Optimization process by Taguchi method suggested that the optimal conditions for the removal of n-hexadecane in a soil-slurry system are as follows: the initial n-hexadecane concentration as sole source of carbon in soil, Na2HPO4.12H2O as phosphorus source at the concentration of 300 mg per kg of soil and, finally, level of significance for the study parameters were 74.31, 6.48 and 8.51, respectively. In conclusion, bioaugmentation of soil with n-hexadecane-degrading bacteria providing an adequate supply of phosphorus source may enhance the biodegradation rate in a polluted soil.</p>

Enhanced Biosynthesis of Laccase and Concomitant Degradation of 2, 3-Dichlorodibenzo-p-Dioxin by Pleurotus florid

Objective: Laccase enzyme has proven to be an excellent catalyst for the degradation of dioxin into less toxic metabolites. In the present study, submerged culture conditions of Pleurotus florida were optimized by Taguchi design of experiments (DOE) for enhanced laccase production and 2, 3-Dichlorodibenzo-p-dioxin (2, 3-DCDD) degradation. Methods/Statistical Analysis: An orthogonal array layout of L-8 (27 ) was constructed using Qualitek-4 software with seven influential factors at two levels with “bigger is better” quality character. Findings: At individual levels, copper showed maximum effect and at the interactive level RPM accounted for more than 90 % of the severity index (SI) with duration. The optimized conditions: nitrogen 0.2 mM; copper 0.04 mM; pH 5.5; temperature 25ºC, inoculum size 10% w/v, RPM 120 and 30 days duration predicted an increase of laccase production by 24.4% (621.36 U to 773.04 U) and dioxin (initial concentration of 10 ppm) degradation by 20.2% (83.1% to 100%). The validation experiments confirmed an improvement of laccase production by 21.5% and exhibited complete degradation of 2, 3-DCDD. Application: This is the first report on parametric optimization of laccase production by P. florida by Taguchi DOE and its utilization for complete degradation of chlorinated dioxin molecules. The optimized process parameters can be adopted for the large-scale production of laccase for bioremediation of dioxin. Keywords: Dioxin Degradation, Laccase Enhancement, Optimization, Taguchi Design of Experiments

A novel ionic liquid/polyoxomolybdate based sensor for ultra-high sensitive monitoring of Al(III): Optimization by Taguchi statistical design

A novel ionic liquid electrostatically supported Nano-Cs-polyoxomolybdate modified carbon paste electrode (Nano-IL-PMo12-CPE) has been developed by using 1-n-butyl-3-methylimidazolium tetrafluoroborate (Bmim.BF4) as a superconductive hydrophobic binder. The supramolecular gel (IL-PMo12) exhibits an ordered structure, various physicochemical properties, and specifically as a result of its substantial reversible self-assembly, it can be used as an intelligent ion-exchange smart platform in the carbon paste bulk of the electrode. The provided materials were characterized by XRD, FT-IR, UV–vis, and elemental analyses. As expected, a significant linear correspondence was found between the sensor output signal (emf/mV) and logarithm of Al(III) ion activity with a Nernstian slope of 19.9 (±0.2) mV decade−1 over a wide concentration range of 1.0 × 10−9 to 2.2 × 10−1 mol L−1 (R2 = 0.9997). The sensor considered, exploits an astounding lower limit of detection and short response time of 7.94 × 10−10 mol L−1 and 8 s respectively within the working pH range of 2.0 to 5.0. A statistical design of experimental (Taguchi method with Qualitek-4 software and L16 orthogonal array robust design) was implemented in this work to optimize the process to achieve the least number of experimental runs as much as possible. Ultimately, practical capability of the sensor was investigated successfully by assessment of Al(III) ion quantity in some aqueous samples namely mineral water, Al-Mg syrup, black tea extract, and ore samples (Basalt and Andesite), in perfect agreement with flame atomic absorption spectroscopy (FAAS).

Biosynthesis of Low Molecular Weight Antifungal Protein from Aspergillus giganteus in Batch Fermentation and In-Vitro Assay.

In present study, Taguchi's design of experiment L9 orthogonal array was created using Qualitek-4 software with four most critical factors namely, K2HPO4, MgSO4, CaCl2 and culture pH. Production of a new intracellular antifungal protein in submerged fermentation was optimized with yield of 0.98±0.1 mg/gram dry cell weight mycelia from Aspergillus giganteus MTCC 8408. The average molecular mass of the purified protein was figured as 5.122 kDa using Electro Spray Ionization-Mass Spectrometry. Scanning electron microscopy was used to correlate the effect of selected factors on fungal cell morphology and its metabolite production. In vitro antifungal susceptibility assay was profiled against Aspergillus niger and minimum inhibitory concentrations were in the range 0.3±0.06 µg/ml. The stronger influencing factors on afp production and mycelial biomass were noted with CaCl2 and K2HPO4 respectively. The validation experiments using optimized conditions confirmed an improvement in afp by 3.86 times with mycelial biomass by 1.52 times, compared to the basal medium. The present statistical optimization study revealed an opportunity to promote economical design at the industrial level for future scale up of effective antifungal agent against systemic aspergillosis as well as possible post harvest loss.

New approach for the biodecolorization of Remazol Black-B (RB-B) by Streptomyces hygroscopicus strain PTCC1132

The textile industry is a rapidly developing industrial sector that produces – wastewater laden with various pollutants including synthetic dyes and heavy metals. Remazol Black-B (RB-B) is a group of azo dyes that are extensively used in textile industries. The objective of this study was to evaluate the potential of the Streptomyces hygroscopicus PTCC1132 to remove RB-B and to determine optimal conditions for decolorizing. The Taguchi optimization approach was used to reduce the number of experiments and the time needed to find optimum conditions. The effect of operating parameters such as temperature, pH, initial RB-B concentrations, and salt dosage were evaluated by defined factor 4 on four-level Taguchi L16 orthogonal array. Qualitek-4 software was used for data analysis. Maximum efficiency for RB-B decol- orization was obtained at 33°C; wherein the solution pH was set to 9.0; and RB-B concentration and salt concentration were 5,000 mg/L and 1%, respectively. The corresponding decolorization efficiency was obtained as 95.27% at under optimized conditions confirming that the bacteria exhibits resistance against the toxic effects of RB-B, especially at high dye concentrations. Our findings indicate of the effectiveness of the evaluated microorganisms for the removal of RB-B from dye-containing effluents.

Biosynthesis of TiO2 and ZnO nanoparticles by Halomonas elongata IBRC-M 10214 in different conditions of medium.

Introduction: In the recent years, green synthesis is a novel method without some disadvantages of physical and chemical methods. In this approach, bacteria, archaebacteria, fungi, and plants may be applied without utilizing toxic and expensive materials for metal nanoparticles (MNPs) preparation. Methods: In this study, we used Taguchi method to obtain optimum conditions in titanium dioxide and zinc oxide nanoparticle (NPs) biosynthesis by Halomonas elongata IBRC-M 10214. Design and analysis of Taguchi experiments (an orthogonal assay and analysis of variance [ANOVA]) carried out by the Qualitek-4 software. Effects of TiO(OH)2, incubation temperature, and culturing time for synthesis of TiO2 NPs as well as ZnCl2 concentration, glucose concentration, and incubation temperature for the preparation of ZnO NPs were evaluated as the controllable factors with 3 levels. Characterization of TiO2 and ZnO NPs were determined by UV-Vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and dynamic light scattering (DLS) analysis. Also, the antimicrobial properties of these NPs were investigated based on agar diffusion assay of NPs dispersed in batch cultures using Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 43300 as multidrug-resistant (MDR) bacteria. Results: It was evaluated that TiO2 and ZnO NPs had respectively average diameter sizes of 104.63±27.75 and 18.11±8.93 nm with spherical shapes. In contrast to the TiO2 NPs without antibacterial activity, the ZnO NPs had antibacterial effects at 0.1 and 0.01 M of (ZnCl2). Conclusion: The ZnO NPs have the antibacterial effect that can be operative in the medicinal aspect for fighting against prominent MDR bacteria such as E. coli ATCC 25922 and S. aureus ATCC 43300. In total, this study presents a simple method in the biosynthesis of TiO2 and ZnO NPs with low the expense, eco-friendly, and high productivity properties.

Microwave absorption properties of GO nanosheets-BaFe12O19–NiO nanocomposites based on epoxy resin: optimization using Taguchi methodology

In this study, a new nanocomposite based on epoxy resin content of fillers nanosheets graphene oxide, nickel oxide nanoparticle and barium hexaferrite nanoparticle have been successfully synthesized and their electromagnetic wave absorption properties in 8–12 GHz were evaluated. To save costs and time the Taguchi method was applied to design of experiments. The wt% of fillers, the ratio of nickel oxide to graphene oxide, the sum wt% of nickel oxide and graphene oxide to barium hexaferrite and sample thickness with three levels were studied. The impact of each parameter in the nanocomposite coating was evaluated by Qualitek-4 software. Data analysis indicated that wt% of all fillers, the ratio of NiO to GO, NiO and GO to BaFe12O19 ratio and sample thickness, 19.648, 36.484, 31.995 and 11.823% were contributed in absorption, respectively. The nanocomposite was synthesized with optimal condition had a reflection loss less than − 20 dB in 8–12 GHz frequency range.