Application of Response Surface Methodology to Evaluate Photodynamic Inactivation Mediated by Eosin Y and 530 nm LED against Staphylococcus aureus

Photodynamic antimicrobial chemotherapy (PAC) is an efficient tool for inactivating microorganisms. This technique is a good approach to inactivate the foodborne microorganisms, which are responsible for one of the major public health concerns worldwide—the foodborne diseases. In this work, response surface methodology (RSM) was used to evaluate the interaction of Eosin Y (EOS) concentration and irradiation time on Staphylococcus aureus counts and a sequence of designed experiments to model the combined effect of each factor on the response. A second-order polynomial empirical model was developed to describe the relationship between EOS concentration and irradiation time. The results showed that the derived model could predict the combined influences of these factors on S. aureus counts. The agreement between predictions and experimental observations (R2adj = 0.9159, p = 0.000034) was also observed. The significant terms in the model were the linear negative effect of photosensitizer (PS) concentration, followed by the linear negative effect of irradiation time, and the quadratic negative effect of PS concentration. The highest reductions in S. aureus counts were observed when applying a light dose of 9.98 J/cm2 (498 nM of EOS and 10 min. irradiation). The ability of the evaluated model to predict the photoinactivation of S. aureus was successfully validated. Therefore, the use of RSM combined with PAC is a promising approach to inactivate foodborne pathogens.

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Optimization of biodiesel synthesis under simultaneous ultrasound-microwave irradiation using response surface methodology (RSM)

Green Processing and Synthesis ◽

10.1515/gps-2015-0029 ◽

2015 ◽

Vol 4 (4) ◽

Cited By ~ 3

Author(s):

Seyed Mohammad Safieddin Ardebili ◽

Teymor Tavakoli Hashjin ◽

Barat Ghobadian ◽

Gholamhasan Najafi ◽

Stefano Mantegna ◽

...

Keyword(s):

Response Surface Methodology ◽

Microwave Irradiation ◽

Response Surface ◽

Palm Oil ◽

Catalyst Concentration ◽

Irradiation Time ◽

Operating Conditions ◽

Molar Ratio ◽

Reaction Conditions ◽

Biodiesel Synthesis

AbstractThis work investigates the effect of simultaneous ultrasound-microwave irradiation on palm oil transesterification and uncovers optimal operating conditions. Response surface methodology (RSM) has been used to analyze the influence of reaction conditions, including methanol/palm oil molar ratio, catalyst concentration, reaction temperature and irradiation time on biodiesel yield. RSM analyses indicate 136 s and 129 s as the optimal sonication and microwave irradiation times, respectively. Optimized parameters for full conversion (97.53%) are 1.09% catalyst concentration and a 7:3.1 methanol/oil molar ratio at 58.4°C. Simultaneous ultrasound-microwave irradiation dramatically accelerates the palm oil transesterification reaction. Pure biodiesel was obtained after only 2.2 min while the conventional method requires about 1 h.

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Optimization of Manufacturing Process of Traditional Algerian Jben Cheese Using Response Surface Methodology (RSM)

South Asian Journal of Experimental Biology ◽

10.38150/sajeb.8(1).p31-42 ◽

2018 ◽

Vol 8 (1) ◽

pp. 31-42

Author(s):

M. Amimour ◽

T. Idoui ◽

A. Cheriguene

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Manufacturing Process ◽

Milk Powder ◽

Statistical Design ◽

Polynomial Equation ◽

Enzymatic Extract ◽

Traditional Cheese ◽

Order Polynomial ◽

Predicted Values

The Aim of this study was to develop an optimized method for manufacturing process of traditional Algerian Jben cheese, using response surface methodology (RSM). In order to develop the objective method of making this traditional cheese, several factors have been studied and a Plackett-Burman statistical design was applied. The effects of the four screened factors (enrichment with milk powder, 10 - 20 g/l; pH of milk, 5.75 - 6.75, enzymatic extract dose, 0.5 - 1.5 ml and coagulation temperature 40 - 60 °C) on the response were investigated, using a Box-Behnken statistical design. Multiple regression analysis was used so that experimental data fits to a second-order polynomial equation. This multiple analysis showed that the model explains about 90.73% of the variation. Based on statistical results, it can be noticed that enrichment with milk powder and pH of milk (Ë‚0.0001***) were highly significant factor influincing cheese yield. The optimal production parame-ters that maximized cheese product (20 g/l enrichment with milk powder, 5.75 pH of milk, 1.29 ml enzymatic extract dose and 60°C coagulation temperature) and the maximal predicted cheese yield (52.68 % ) were found out through response surface methodology. Under these conditions, a verification experiment was carried out and cheese yield was found to be 49.46 %. The overall percentage of agreement for the experimental results (more than 93 % validity) with the predicted values indicates the validation of the statistical model and the success of the optimization process.

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Optimization of an Ultrasound-Assisted Extraction Condition for Flavonoid Compounds from Cocoa Shells (Theobroma cacao) Using Response Surface Methodology

Molecules ◽

10.3390/molecules24040711 ◽

2019 ◽

Vol 24 (4) ◽

pp. 711 ◽

Cited By ~ 7

Author(s):

Arief Md Yusof ◽

Siti Abd Gani ◽

Uswatun Zaidan ◽

Mohd Halmi ◽

Badrul Zainudin

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Ethanol Concentration ◽

Irradiation Time ◽

Ultrasound Irradiation ◽

Coefficient Of Determination ◽

Ultrasound Assisted Extraction ◽

Assisted Extraction ◽

Ultrasound Assisted ◽

Experimental Values

This study investigates the ultrasound-assisted extraction of flavonoids from Malaysian cocoa shell extracts, and optimization using response surface methodology. There are three variables involved in this study, namely: ethanol concentration (70–90 v/v %), temperature (45–65 °C), and ultrasound irradiation time (30–60 min). All of the data were collected and analyzed for variance (ANOVA). The coefficient of determination (R2) and the model was significant in interaction between all variables (98% and p < 0.0001, respectively). In addition, the lack of fit test for the model was not of significance, with p > 0.0684. The ethanol concentration, temperature, and ultrasound irradiation time that yielded the maximum value of the total flavonoid content (TFC; 7.47 mg RE/g dried weight (DW)) was 80%, 55 °C, and 45 min, respectively. The optimum value from the validation of the experimental TFC was 7.23 ± 0.15 mg of rutin, equivalent per gram of extract with ethanol concentration, temperature, and ultrasound irradiation time values of 74.20%, 49.99 °C, and 42.82 min, respectively. While the modelled equation fits the data, the T-test is not significant, suggesting that the experimental values agree with those predicted by the response surface methodology models.

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Response surface methodology as an efficient tool for optimizing the Fischer–Tropsch process over a novel Fe–Mn nano catalyst

RSC Advances ◽

10.1039/c6ra10678a ◽

2016 ◽

Vol 6 (83) ◽

pp. 80099-80105 ◽

Cited By ~ 2

Author(s):

B. Sedighi ◽

M. Feyzi ◽

M. Joshaghani

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Surface Area ◽

Fischer Tropsch ◽

Efficient Tool ◽

Nano Catalyst

A novel Fe–Mn–resol/SiO2 nano-catalyst with improved surface area and porosity was prepared and used in the Fischer–Tropsch process.

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Enhanced Alkali Pretreatment of Narrow Leaves Cattail by Response Surface Methodology

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.875-877.1637 ◽

2014 ◽

Vol 875-877 ◽

pp. 1637-1641

Author(s):

Arrisa Sopajarn ◽

Chayanoot Sangwichien

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Residence Time ◽

Preliminary Test ◽

Polynomial Equation ◽

Alkali Concentration ◽

Pretreatment Condition ◽

Order Polynomial ◽

Optimized Conditions ◽

Central Composite

The purpose of this work is to develop a pretreatment process of lingo-cellulosic ethanol production from narrow leaves cattail (Typha angustifolia) by using alkali catalysis with the response surface methodology (RSM) as a central composite design (CCD). The first step, LiOH, NaOH, and KOH were used as catalytic alkali for preliminary test. Second, the suitable alkali from first step was selected to optimize of pretreatment condition of three independent variables (alkali concentration, temperature, and residence time) that varies at CCD five codes (-2, -1, 0, 1, 2). Sodium hydroxide (NaOH) is the proper alkali because it could increase cellulose more than KOH and nearby LiOH while it is cheapest. RSM result shows the optimized pretreatment condition based on cellulose increased which obtained from this study that is NaOH 5 % w/v at 100 °C and residence time for 120 min. Beside, this condition was analyzed using an ANOVA with a second order polynomial equation after eliminated non-significant terms. At the optimized conditions, cellulose increased, hemicellulose decreased and weight recovery were achieved 77.81%, 80.59, and 41.65%, respectively. Moreover, the model was reasonable to predict the response of strength with less than 5% error.

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Optimization of Biodiesel Ultrasound-Assisted Synthesis from Castor Oil Using Response Surface Methodology (RSM)

Chemical Product and Process Modeling ◽

10.1515/cppm-2014-0013 ◽

2015 ◽

Vol 10 (2) ◽

pp. 123-133 ◽

Cited By ~ 4

Author(s):

Mohammadreza Sabzimaleki ◽

Barat Ghobadian ◽

Mohsen Mazloom Farsibaf ◽

Gholamhassan Najafi ◽

Masoud Dehghani Soufi ◽

...

Keyword(s):

Response Surface Methodology ◽

Reaction Time ◽

Response Surface ◽

Castor Oil ◽

Molar Ratio ◽

Reaction Yield ◽

Ultrasound Assisted ◽

Short Time ◽

The Relationship ◽

Central Composite

Abstract Production of biodiesel from castor oil (CO) using ultrasound-assisted has been investigated in this study. The objective of the present work was therefore to determine the relationship between various important parameters of the alkaline-catalyzed transesterification process to obtain a high reaction yield in a short time. The response surface methodology (RSM) was used to statistically analyze and optimize the operating parameters of the process. A central composite design (CCD) was approved to study the effects of the reaction time, the methanol to oil molar ratio, the ultrasonic cycle and the ultrasonic amplitude on reaction yield. The optimum conditions for alkaline-catalyzed transesterification of CO was found to be a reaction time of 540 s, methanol to oil molar ratio of 8.15:1,ultrasonic cycle of 0.73% and ultrasonic amplitude 64.34%. By exerting the calculated optimum condition in the process, the reaction yield reached 87.0494%. The results from the RSM analysis indicated that the reaction time has the most significant effect on the reaction yield.

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Application of Response Surface Methodology to Enhance Phenol Removal from Refinery Wastewater by Microwave Process

International Journal of Microwave Science and Technology ◽

10.1155/2014/639457 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 6

Author(s):

Sherif A. Younis ◽

Waleed I. El-Azab ◽

Nour Sh. El-Gendy ◽

Shuokr Qarani Aziz ◽

Yasser M. Moustafa ◽

...

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Output Power ◽

Petroleum Refinery ◽

Irradiation Time ◽

Reaction Rates ◽

Design Parameters ◽

Phenol Removal ◽

Refinery Wastewater ◽

Petroleum Refinery Wastewater

Phenol contaminated petroleum refinery wastewater presents a great threat on water resources safety. This study investigates the effect of microwave irradiation on removal of different concentrations of phenol in an attempt for petroleum refinery wastewater treatment. The obtained results show that the MW output power and irradiation time have a significant positive effect on the removal efficiency of phenol. The kinetic reaction is significantly affected by initial MW output power and initial phenol concentrations. Response surface methodology (RSM) was employed to optimize and study the interaction effects of process parameters: MW output power, irradiation time, salinity, pH, and H2O2 concentration using central composite design (CCD). From the CCD design matrix, a quadratic model was considered as an ultimate model (R2 = 0.75) and its adequacy was justified through analysis of variance (ANOVA). The overall reaction rates were significantly enhanced in the combined MW/H2O2 system as proved by RSM. The optimum values for the design parameters of the MW/H2O2 process were evaluated giving predicted phenol removal percentage of 72.90% through RSM by differential approximation and were confirmed by experimental phenol removal of 75.70% in a batch experiment at optimum conditions of 439 W MW power, irradiation time of 24.22 min, salinity of 574 mg/L, pH 5.10, and initial H2O2 concentration of 10% (v/v).

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Optimum Parameters for Extracting Three Kinds of Carotenoids from Pepper Leaves by Response Surface Methodology

Separations ◽

10.3390/separations8090134 ◽

2021 ◽

Vol 8 (9) ◽

pp. 134

Author(s):

Nenghui Li ◽

Jing Li ◽

Dongxia Ding ◽

Jianming Xie ◽

Jing Zhang ◽

...

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Dry Weight ◽

Optimum Parameters ◽

Order Polynomial ◽

Pepper Leaves ◽

New Varieties ◽

Weak Light ◽

Experimental Values ◽

Optimum Extraction

To determine the optimum parameters for extracting three carotenoids including zeaxanthin, lutein epoxide, and violaxanthin from pepper leaves by response surface methodology (RSM), a solvent of acetone and ethyl acetate (1:2) was used to extract carotenoids with four independent factors: ultrasound time (20–60 min); ratio of sample to solvent (1:12–1:4); saponification time (10–50 min); and concentration of saponification solution (KOH–methanol) (10–30%). A second-order polynomial model produced a satisfactory fitting of the experimental data with regard to zeaxanthin (R2 = 75.95%, p < 0.0197), lutein epoxide (R2 = 90.24%, p < 0.0001), and violaxanthin (R2 = 73.84%, p < 0.0809) content. The optimum joint extraction conditions of zeaxanthin, lutein epoxide, and violaxanthin were 40 min, 1:8, 32 min, and 20%, respectively. The optimal predicted contents for zeaxanthin (0.823022 µg/g DW), lutein epoxide (4.03684 µg/g dry; DW—dry weight), and violaxanthin (16.1972 µg/g DW) in extraction had little difference with the actual experimental values obtained under the optimum extraction conditions for each response: zeaxanthin (0.8118 µg/g DW), lutein epoxide (3.9497 µg/g DW), and violaxanthin (16.1590 µg/g DW), which provides a theoretical basis and method for cultivating new varieties at low temperatures and weak light resistance.

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Application of the response surface methodology for the evaluation of Staphylococcus aureus inhibition with Ag/TiO2 nanoparticles

10.21203/rs.3.rs-617251/v1 ◽

2021 ◽

Author(s):

M.A. Olivares-Ramírez ◽

Leticia López-Zamora ◽

M.J. Peña-Juárez ◽

E.J. Gutiérrez-Castañeda ◽

J.A. Gonzalez-Calderon

Keyword(s):

Staphylococcus Aureus ◽

Response Surface Methodology ◽

Response Surface ◽

Statistical Significance ◽

Antimicrobial Effect ◽

Quadratic Model ◽

Coefficient Of Determination ◽

Poly Lactic Acid ◽

P Value ◽

Zone Of Inhibition

Abstract The present work shows the implementation of the Response Surface Methodology (RSM), fed by an experimental Central Composite Design (CCD) to find the conditions that allow maximizing the inhibition of the microorganism Staphylococcus aureus with nanoparticles of TiO2 silanized with 3-Aminopropyltriethoxysilane (APTES) and doped with Ag. In addition, Poly(lactic) acid composites were prepared with these Ag/TiO2 nanoparticles with the aim to confer their antimicrobial effect. The independent variables considered were pH, AgNO3/TiO2 ratio (% w/w), and TiO2 nanoparticles concentration (g/250 mL), and as the variable of response, the length of the diameter of the halo or zone of inhibition presented by the microorganism (mm). Statistical analysis found that maximization of S. aureus inhibition occurs at intermediate levels with a value of 10 for pH and 5 g of TiO2 solids, while for the concentration of AgNO3 high levels are required, greater than 10% w/w. Likewise, the statistical significance was determined using the Student's t-test and the p-value; it was found that the significant effect corresponds to the concentration of AgNO3, so a second experimental CCD design equirradial with two factors was considered, estimating AgNO3 concentration and TiO2 amount, the pH at constant 10 value. The second experimental design indicated that maximization in S. aureus inhibition occurs at an AgNO3 concentration between 20-25% w/w with high amounts of TiO2 solids (7-8 g), with a resulting zone of inhibition between 26-28 mm. The quadratic model obtained, which represents the relationship between the length of the zone of inhibition with the variables considered, shows an adjustment of experimental data with a coefficient of determination (R2) of 0.82.

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A Study on Ductility of Prestressed Concrete Pier Based on Response Surface Methodology

Engineering, Technology & Applied Science Research ◽

10.48084/etasr.855 ◽

2016 ◽

Vol 6 (6) ◽

pp. 1253-1257

Author(s):

H. Wang ◽

Y. Zhang ◽

S. Qin

Keyword(s):

Compressive Strength ◽

Response Surface Methodology ◽

Response Surface ◽

Prestressed Concrete ◽

Reinforcement Ratio ◽

Longitudinal Reinforcement ◽

Shear Reinforcement ◽

Concrete Compressive Strength ◽

Curvature Ductility ◽

The Relationship

The ductility of prestressed concrete pier is studied based on response surface methodology. Referring to the pervious prestressed concrete pier, based on Box-Behnken design, the ductility of 25 prestressed concrete piers is calculated by numerical method. The relationship between longitudinal reinforcement ratio, shear reinforcement ratio, prestressed tendon quantity, concrete compressive strength and ductility factor is gotten. The influence of the longitudinal reinforcement ratio, the shear reinforcement ratio, the prestressed tendon quantity and concrete compressive strength to curvature ductility is discussed. Then the ductility regression equation is deduced. The result showed that the influence of the prestressed tendon quantity to the ductility of prestressed concrete pier is significant. With the increasing of the prestressed tendon quantity, the curvature ductility curved reduces. With the increasing of shear reinforcement ratio and compressive strength of concrete, the curvature ductility increases linearly. And the influence of the longitudinal reinforcement ratio to ductility of the prestressed concrete pier is insignificant.

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