Central Composite Design Methodology Research Articles

Statistical Approach for the Production of Protease and Cellulase from Bacillus cereus KA3

A cheap agro-industrial waste was used as the substrate for the production of protease and cellulase from Bacillus cereus KA3. The process parameters were optimized by a two level full factorial design and response surface methodology. Two level full factorial designs revealed that the factors namely, pH, peptone and NaH2PO4 were significantly influenced on the production of protease and cellulase. These three significant factors were selected for central composite design and response surface methodology. The maximum protease and cellulase production was 3127 U/g, and 482 U/g, respectively, after statistical approach, which showed over fourfold increase in enzyme production than unoptimized medium.

Isotherms and kinetic study of ultrasound-assisted adsorption of malachite green and Pb2+ ions from aqueous samples by copper sulfide nanorods loaded on activated carbon: Experimental design optimization

Copper sulfide nanorods loaded on activated carbon (CuS-NRs-AC) was synthesized and used for simultaneous ultrasound-assisted adsorption of malachite green (MG) and Pb2+ ions from aqueous solution. Following characterization of CuS-NRs-AC were investigated by SEM, EDX, TEM and XRD, the effects of pH (2.0–10), amount of adsorbent (0.003–0.011g), MG concentration (5–25mgL−1), Pb2+ concentration (3–15mgL−1) and sonication time (1.5–7.5min) and their interactions on responses were investigated by central composite design (CCD) and response surface methodology. According to desirability function on the Design Expert optimum removal (99.4%±1.0 for MG and 68.3±1.8 for Pb2+ions) was obtained at pH 6.0, 0.009g CuS-NRs-AC, 6.0min mixing by sonication and 15 and 6mgL−1 for MG and Pb2+ ions, respectively. High determination coefficient (R2>0.995), Pred-R2-value (>0.920) and Adju-R2-value (>0.985) all are good indication of best agreement between the experimental and design modelling. The adsorption kinetics follows the pseudo-second order model and adsorption isotherm follows the Langmuir model with maximum adsorption capacity of 145.98 and 47.892mgg−1 for MG and Pb2+ ions, respectively. This adsorbent over short contact time is good choice for simultaneous removal of large content of both MG and Pb2+ ions from wastewater sample.

Optimization of carbofuran degradation in microwave-granular activated carbon system using response surface methodology

Present study revealed tremendous improvement in carbofuran degradation in a Microwave – Granular Activated carbon (MW-GAC) system compared to natural hydrolysis process and the degradation half-life was 12 and 0.189min at a pH of 6 and 10 respectively at a reaction temperature of 80°C. In addition, the effect of several operating parameters such as carbofuran concentration, MW output power and reaction time was modelled using Central composite design (CCD) and response surface methodology (RSM) with 17 experimental runs. Carbofuran degradation/mineralization process was described in terms of carbofuran concentration, MW output power and reaction time. The experimental outcomes from CCD indicated improved degradation and mineralization of carbofuran with the increase in reaction time. On the other hand, lower MW output power resulted in poor degradation and mineralization of carbofuran. RSM showed highest correlation coefficient for carbofuran removal per MW output power, Rw (0.92) and COD removal efficiency, ηCOD (0.82). Therefore, quadratic models were developed using regression analysis to predict Rw and ηCOD. Good correlation between the observed values and predicted values by the developed models indicated that the developed models can be used to design required Rw and ηCOD within the experimental conditions.

Concentrated landfill leachate treatment with a combined system including electro-ozonation and composite adsorbent augmented sequencing batch reactor process

Abstract A large volume of concentrated leachate is generated from leachate treatment via reverse osmosis. Concentrated leachate is a dark brown solution with high levels of pollutants. Treating concentrated leachate is extremely difficult, and thus, a combined treatment system is suggested. In the present study, concentrated landfill leachate was treated using a combined treatment technique that included electro-ozonation and a composite adsorbent augmented sequencing batch reactor (SBR) process. Central composite design and response surface methodology were utilized to investigate experimental data. Reaction time (30–120 min) and ozone concentration (40–120 mg/L) were selected as the independent variables. At an optimum reaction time (96.9 min) and ozone dosage (120.0 mg/L), the removal efficacies of chemical oxygen demand (COD), color, and nickel were 64.8%, 90.4%, and 52.9%, respectively, at original pH (7.3), as well as current and voltage of 4 A and 9 V, respectively. Ozone utilization ranged from 0.3 kg to 1.4 kg COD removed per kg ozone consumed. After treatment at optimum electro-ozonation performance, concentrated leachate was transferred to the powdered composite adsorbent (P-BAZLSC) augmented SBR reactor (PB-SBR). PB-SBR improved the removal efficiency for COD, color, and nickel from 64.8% to 88.2%, from 90.4% to 96.1%, and from 52.9% to 73.4%, respectively.

Comparison of two microextraction methods based on solidification of floating organic droplet for the determination of multiclass analytes in river water samples by liquid chromatography tandem mass spectrometry using Central Composite Design

Two low density organic solvents based liquid–liquid microextraction methods, namely Vortex assisted liquid–liquid microextraction based on solidification of floating organic droplet (VALLME-SFO) and Dispersive liquid–liquid microextraction based on solidification of floating organic droplet(DLLME-SFO) have been compared for the determination of multiclass analytes (pesticides, plasticizers, pharmaceuticals and personal care products) in river water samples by using liquid chromatography tandem mass spectrometry (LC–MS/MS). The effect of various experimental parameters on the efficiency of the two methods and their optimum values were studied with the aid of Central Composite Design (CCD) and Response Surface Methodology(RSM). Under optimal conditions, VALLME-SFO was validated in terms of limit of detection, limit of quantification, dynamic linearity range, determination of coefficient, enrichment factor and extraction recovery for which the respective values were (0.011–0.219ngmL−1), (0.035–0.723ngmL−1), (0.050–0.500ngmL−1), (R2=0.992–0.999), (40–56), (80–106%). However, when the DLLME-SFO method was validated under optimal conditions, the range of values of limit of detection, limit of quantification, dynamic linearity range, determination of coefficient, enrichment factor and extraction recovery were (0.025–0.377ngmL−1), (0.083–1.256ngmL−1), (0.100–1.000ngmL−1), (R2=0.990–0.999), (35–49), (69–98%) respectively. Interday and intraday precisions were calculated as percent relative standard deviation (%RSD) and the values were ≤15% for VALLME-SFO and DLLME-SFO methods. Both methods were successfully applied for determining multiclass analytes in river water samples.

A green method for production of nanobiochar by ball milling- optimization and characterization

Environmental considerations along with the technological challenges have led to search for green and energy-efficient processes for advanced nanostructured materials. In this study, nanobiochar was produced from pine wood biochar using a planetary ball mill. A central composite experimental design and response surface methodology was employed to optimize the ball milling parameters including time, rotational speed and ball to powder mass ratio to obtain nanoparticles in short time and at lower energy consumption. ANOVA results showed that the linear and quadratic effect estimates of time and the interaction effect of time and rotational speed were significant contributors to the size of particles during milling (p < 0.05). Based on the developed statistical model, the optimum conditions for obtaining the smallest particles, around 60 nm, were found to be 1.6 h, 575 rpm and 4.5 g/g. However, the size measurements indicated that particles had a great tendency to agglomerate. Further study showed that the conditioning of biochar at cryogenic temperatures prior to milling inhibits the agglomeration of nanoparticles which is essential in industrial processes. The adsorption test proved that the nanobiochar produced using green method is promising in the removal of micropollutants from aqueous media by removing up to 95% of carbamazepine from water. At the optimum milling parameters and conditioning for 24 h at −80 °C, nanobiochar with the average size of around 60 nm was obtained. The produced nanobiochar was characterized by Brunauer-Emmett-Teller (BET) gas porosimetry, scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Also, physical and chemical properties, such as water holding capacity, organic matter, oxidation-reduction potential (ORP), elemental composition, polycyclic aromatic hydrocarbons (PAHs) and heavy metals were analyzed.

Production of High Quality Fish Oil by Enzymatic Protein Hydrolysis from Cultured Atlantic Salmon By-Products: Investigation on Effect of Various Extraction Parameters Using Central Composite Rotatable Design

Salmon oil was extracted from cultured Atlantic salmon by-product mix (head, frame and viscera) through enzymatic extraction, with experimental combinations of different enzyme (Sea-B-Zyme L200 enzyme) concentrations (0.09–2.91%) and temperature levels (38–52 °C), generated and analyzed through Central Composite Rotatable design and response surface methodology respectively. The oil content obtained was between 13.09–19.18% of the total weight of the sample, where temperature level was observed as a more significant factor than enzyme concentration and highest oil yield was obtained at enzyme concentration of 2.5% and temperature level 50 °C. Salmon by-product oil predominantly contained mono-unsaturated fatty acids (52.49–54.27%), subsequently poly-unsaturated fatty acids (28.97–30.53%) and saturated fatty acids (14.95–17.91%). The extracted oil was also observed as a potential source of oleic acid, linoleic acid, palmitic acid, palmitoleic acid, stearic acid, vaccenic acid, gondoic acid, α-linoleic acid, DHA, DPA and EPA.

In-situ development of highly photocatalytic multifunctional nanocomposites by ultrasonic acoustic method

Cotton-titania nanocomposites with multifunctional properties were synthesized through ultrasonic acoustic method (UAM). Ultrasonic irradiations were used as a potential tool to develop cotton-titania (CT) nanocomposites at low temperature in the presence of titanium tetrachloride and isopropanol. The synthesized samples were characterized by XRD, SEM, EDX and ICP-OES methods. Functional properties i.e. Ultraviolet protection factor (UPF), self-cleaning, washing durability, antimicrobial and tensile strength of the CT nanocomposites were evaluated by different methods. Central composite design and response surface methodology were employed to evaluate the effects of selected variables on responses. The results confirm the simultaneous formation and incorporation of anatase TiO2 with average crystallite size of 4nm on cotton fabric with excellent photocatalytic properties. The sustained self-cleaning efficiency of CT nanocomposites even after 30 home launderings indicates their excellent washing durability. Significant effects were obtained during statistical analysis for selected variables on the formation and incorporation of TiO2 nanoparticles (NPs) on cotton and photocatalytic properties of the CT nanocomposites.

Supramolecular-based solvent microextraction of carbaryl in water samples followed by high performance liquid chromatography determination

ABSTRACTIn this study, a simple, rapid, low cost, sensitive and environmentally friendly technique, supramolecular solvent microextraction (SM-SME) followed by high performance liquid chromatography-ultraviolet has been proposed to extract carbaryl from water samples. Parameters, affecting the SM-SME performance such as the weight of decanoic acid (DeA), volume of tetrahydrofuran (THF), pH and salt concentration, were studied and optimised. The effect of the pH on the extraction efficiency was evaluated by one–factor-at-a-time methodology, but the other variables were optimised by a face-centred cube central composite design methodology. Optimum extraction conditions were obtained: DeA: 70 mg; THF: 650 µL; salt concentration: 10% (w/v) NaCl and pH = 2–4), and the performance of the proposed method was evaluated. Under the optimum conditions, good linearity (1.0–500 µg L−1, r2 = 0.9994) was obtained. Limit of detection and limit of quantification were 0.3–1.0 µg L−1, respectively. Also, the recoveries of the carbaryl were obtained in the ranged from 96% to 105%. Finally, proposed method was successfully applied for the determination of the carbaryl in the water samples of farms run-off and rivers and satisfactory results were obtained.

Sonochemical synthesis of highly crystalline photocatalyst for industrial applications

Highly photo active pure anatase form of TiO2 nanoparticles with average particle size 4nm have been successfully synthesized by ultrasonic acoustic method (UAM). The effects of process variables i.e. precursors concentration and sonication time were investigated based on central composite design and response surface methodology. The characteristics of the resulting nanoparticles (RNP) were analyzed by scanning electron microscopy, dynamic light scattering, transmission electron microscopy, X-ray diffractometry and Raman spectroscopy. Photocatalytic experiments were performed with methylene blue dye which is considered as model organic pollutant in textile industry. A comparative analysis between the RNP and commercially available Degussa P25 for photocatalytic performance against dye removal efficiency was performed. The rapid removal of methylene blue in case of RNP indicates their higher photocatalytic activity than P25. Maximum dye removal efficiency 98.45% was achieved with optimal conditions i.e. TTIP conc. 10mL, EG conc. 4mL and sonication time 1h. Interestingly, no significant difference was found in the photocatalytic performance of RNP after calcination. Moreover, self-cleaning efficiency of RNP deposited on cotton was evaluated in RGB color space. The obtained results indicate the significant impact of ultrasonic irradiations on the photocatalytic performance of pure anatase form than any other hybrid type of TiO2 nanoparticles.

Bioregeneration of spent mercury bearing sulfur-impregnated activated carbon adsorbent.

Among various adsorbents studied, sulfur-impregnated activated carbon is one of the most promising adsorbents for mercury removal from flue gas. However, a large amount of spent activated carbons containing high content of mercury are generated after adsorption. To make the adsorption a more viable option, the regeneration and reuse of the spent activated carbon should be considered. The purpose of this study is to develop a novel technique for bioregeneration of sulfur-impregnated activated carbons after adsorption of mercury from flue gases by sulfur-oxidizing bacteria. The optimal operating parameters for this bioregeneration process were studied using central composite design (CCD) and response surface methodology (RSM). Results showed that the sulfur oxidation rate was increased with increasing activated carbon dosage. Furthermore, the increase of inoculum size only caused a slight increase of sulfur oxidation rate in the bioregeneration. The maximum mercury removal efficiency of more than 50% was obtained at 10% (w/v) activated carbon dosage and 20% (v/v) inoculum size. After the bioregeneration process, Brunauer-Emmett-Teller (BET) surface area and micropore volume of spent activated carbon increased due to the bio-oxidation of mercury bearing sulfur on the surface of activated carbons.

Heat Pre-Treatment of Beverages Wastewater on Hydrogen Production

At present, a large variety of alternative fuels have been investigated and hydrogen gas is considered as the possible solution for the future due to its unique characteristics. Through dark fermentation process, several factors were found to have significant impact on the hydrogen production either through process enhancement or inhibition and degradation rates or influencing parameters. This work was initiated to investigate the optimum conditions for heat pre-treatment and initial pH for the dark fermentative process under mesophilic condition using a central composite design and response surface methodology (RSM). Different heat treatment conditions and pH were performed on the seed sludge collected from the anaerobic digester of beverage wastewater treatment plant. Heat treatment of inoculum was optimized at different exposure times (30, 90, 120 min), temperatures (80, 90 and 100°C) and pH (4.5, 5.5, 6.5) in order to maximize the biohydrogen production and methanogens activity inhibition. It was found that the optimum heat pre-treatment condition and pH occurred at 100°C for 50 min and the pH of 6.00. At this optimum condition the hydrogen yield was 63.0476 ml H2/mol glucose (H2 Yield) and the COD removal efficiency was 90.87%. In conclusion, it can be hypothesized that different heat treatment conditions led to differences in the initial microbial communities (hydrogen producing bacteria) which resulted in the different hydrogen yields.

Optimization of EPS Production and Characterization by a Halophilic Bacterium, Kocuria rosea ZJUQH from Chaka Salt Lake with Response Surface Methodology.

With the rising awareness of microbial exopolysaccharides (EPSs) application in various fields, halophilic microorganisms which produce EPSs have received broad attention. A newly identified Kocuria rosea ZJUQH CCTCC M2016754 was determined to be a moderate halobacterium on account of its successful adaption to the environment containing 10% NaCl. The optimal combination of fermentation medium compositions on EPS production was studied. In this work, a fractional factorial design was adopted to investigate the significant factors that affected EPS production. The factors of KCl and MgSO4 were found to have a profound impact on EPS production. We utilized central composite design and response surface methodology to derive a statistical model for optimizing the submerged culture medium composition. Judging from these experimental results, the optimum culture medium for producing EPSs was composed of 0.50% casein hydrolysate, 1.00% sodium citrate, 0.30% yeast extract, 0.50% KCl, 0.50% peptone, and 5.80% MgSO4 (initial pH 7.0). The maximal EPS was 48.01 g/L, which is close to the predicted value (50.39 g/L). In the validation experiment, the highest concentration of 70.64 g/L EPSs was obtained after 120 h under the optimized culture medium in a 5-L bioreactor. EPS from this bacterium was also characterized by differential scanning calorimetry (DSC) and Fourier transform infrared analysis (FT-IR). The findings in this study imply that Kocuria rosea ZJUQH has great potential to be exploited as a source of EPSs utilized in food, the pharmaceutical and agriculture industry, and in the biotreatment of hypersaline environments.

A new approach to obtain cellulose nanocrystals and ethanol from eucalyptus cellulose pulp via the biochemical pathway.

The feasibility of integration of cellulosic ethanol production with the manufacture of cellulose nanofibers (CNF) and cellulose nanocrystals (CNC) was evaluated using eucalyptus cellulose pulp as feedstock and employing the biochemical route alone. For the enzymatic hydrolysis step, experimental central composite design (CCD) methodology was used as a tool to evaluate the effects of solids loading (SL) and enzymatic loading (EL) on glucose release and cellulose conversion. Glucose concentrations from 45 to 125 g/L were obtained after 24 h, with cellulose conversions from 35 to 96%. Validation of the statistical model was performed at SL of 20% and EL of 10 mg protein/g, which was defined by the desirability function as the optimum condition. The sugars released were used for the production of ethanol by Saccharomyces cerevisiae, resulting in 62.1 g/L ethanol after 8 h (yield of 95.5%). For all the CCD experimental conditions, the residual solids presented CNF characteristics. Moreover, the use of a new strategy with temperature reduction from 50 to 35°C after 24 h of enzymatic hydrolysis enabled CNC to be obtained after 144 h. The CNC showed a crystallinity index of 83%, length of 260 nm, diameter of 15 nm, and aspect ratio (L/D) of 15. These characteristics are suitable for many applications, such as reinforcement in polymeric materials and other lower volume higher value bio-based products. The findings indicate the viability of obtaining ethanol and CNC using the biochemical route exclusively, potentially contributing to the future implementation of forest biorefineries. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1085-1095, 2017.

In-tube electrochemically controlled solid phase microextraction of amitriptyline, imipramine and chlorpromazine from human plasma by using an indole-thiophene copolymer nanocomposite

The paper introduces a novel poly(indole-co-thiophene) composite for on-line electrochemically controlled solid-phase microextraction (SPME) of the antidepressant drugs amitriptyline (AMI), imipramine (IMI), and chlorpromazine (CPZ). The poly(In-co-Th) coating was prepared by electropolymerization and deposition on the internal surface of a stainless steel tube. An online SPME-HPLC system is obtained by replacing the sample loop of a six-port injection valve by the modified tube. The morphology and surface properties of the composite coating were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. Central composite design and response surface methodology were used to optimize the voltage applied, adsorption and desorption times, the pH value of the sample solution, sample flow rate and acid concentration of the desorption eluent. Following elution with 10 mM HNO3 in methanol, the drugs were quantified by HPLC with UV detection at 210 nm. The method displays a linear response in the 35 to 1000 ng mL−1 drug concentration range in case of spiked water samples. In case of plasma samples, the range extends from 80 to 1000 ng mL−1. Other figures of merit include (a) limits of detection of <40 ng mL−1, (b) recoveries from spiked samples within the 24–64% range, (c) intra- and inter-day precisions (RSDs; for n = 3) of <3.5% (at a concentration of 200 ng mL−1), and (d), relative recoveries within the range of 82.5–120%. This in-tube method was successfully applied to the analysis of the 3 drugs in human plasma samples.

β-Cyclodextrin modified mesoporous silica nanoparticles as a nano-carrier: Response surface methodology to investigate and optimize loading and release processes for curcumin delivery

β-Cyclodextrin functionalized PEGylated porous silica nanoparticles KIT-6 (denoted as [β-CD@PEGylated KIT-6] NPs) is synthesized and evaluated as an efficient and reliable pH-sensitive nano-carrier. Curcumin (CUR), an anticancer drug, has low solubility and stability and these properties diminished its bioavailability. One way to overcome this problem is employing nano-carrier for delivery of CUR. In this study, the novel [β-CD@PEGylated KIT-6] NPs nano-carrier was employed for CUR delivery successfully. The nano-DDS was characterized using different techniques such as X-ray powder diffraction (XRD), transmission and scanning electron microscopy (TEM and SEM), Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimeter (DSC), N2 adsorption–desorption measurement, and dynamic light scattering (DLS). In this study, first, the combination of central composite design (CCD) and response surface methodology (RSM) was used to achieve the optimal condition of the loading step with investigation of two important factors: the loading time and the weight ratio of drug to nano-carrier. Maximum loading efficiency 88.55% was obtained at 43h of loading time and 1.22 of the weight ratio. Then CUR was loaded onto the nano-carrier at this optimal condition and its released was investigated by CCD-RSM. The maximum drug release was obtained at 5.16 of pH and 107h of release time.

Effect of machining characteristics of nano-TiC mixed dielectric fluids on Inconel 718 in the EDM process

Abstract Among the nontraditional machining process, electrical discharge machining (EDM) is one of the significant processes for machining complicated and complex shapes. An experimental investigation was made with the help of electrical discharge machine on Inconel 718 using brass electrode tool to study the vibration behavior in the titanium carbide nanoparticles mixed dielectric fluid environment. Titanium carbide nanoparticles mixed with dielectric fluid possess a high strength, have good electrical and thermal properties and require lesser machining time than pure dielectric fluid. In this experiment, the central composite second order rotatable design and response surface methodology were used to develop an experimental model. Based on the developed models, analyses on machining characteristics of titanium carbide nanoparticles mixed EDM have been carried out. The current, pulse on time and pulse off time were considered as input process parameters and the output process parameters such as material...

Photo‐activated periodate in homogeneous degradation and mineralization of quinoline: Optimization, kinetic, and energy consumption

Aqueous solutions of quinoline (Qu) were treated with photo‐activated potassium periodate (UV/KPI) process. A low consumption, cylindrical photo‐reactor was employed for this purpose. Either KPI oxidant or UV irradiation alone had little effect in Qu degradation; however, the combined UV/KPI process leads to significant degradation and mineralization. Experiments were conducted based on central composite design (CCD) methodology. The established optimized conditions for treatment of 40 mg L−1 of the substrate were [KPI] = 695.5 mg L−1, pH = 4.3 and T = 35.6 °C. Under these conditions, 96.5% degradation and 71.5% mineralization were obtained after 70 min operations. A quadratic equation predicts the variation of degradation efficiency as a function of the influencing parameters. To investigate about the involved species, tert‐butyl alcohol was used as radical scavenger and it was found that the contribution of hydroxyl radical was about 73.1%. Kinetic study revealed that Qu degradation was a pseudo first‐order reaction and the corresponding activation energy was determined. Meanwhile, the required irradiation energy for one order of magnitude degradation was estimated as 3.13 kWh m−3. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 1621–1627, 2017

Development of solid lipid nanoparticles containing total flavonoid extract from Dracocephalum moldavica L. and their therapeutic effect against myocardial ischemia-reperfusion injury in rats.

Total flavonoid extract from Dracocephalum moldavica L. (TFDM) contains effective components of D. moldavica L. that have myocardial protective function. However, the cardioprotection function of TFDM is undesirable due to its poor solubility. In order to improve the solubility and efficacy of TFDM, we developed TFDM-loaded solid lipid nanoparticles (TFDM-SLNs) and optimized the formulation of TFDM-SLNs using central composite design and response surface methodology. The physicochemical properties of TFDM-SLNs were characterized, and the pharmacodynamics was investigated using the myocardial ischemia–reperfusion injury model in rats. The nanoparticles of optimal formulation for TFDM-SLNs were spherical in shape with the average particle size of 104.83 nm and had a uniform size distribution with the polydispersity index value of 0.201. TFDM-SLNs also had a negative zeta potential of −28.7 mV to ensure the stability of the TFDM-SLNs emulsion system. The results of pharmacodynamics demonstrated that both TFDM and TFDM-SLN groups afforded myocardial protection, and the protective effect of TFDM-SLNs was significantly superior to that of TFDM alone, based on the infarct area, histopathological examination, cardiac enzyme levels and inflammatory factors in serum. Due to the optimal quality and the better myocardial protective effect, TFDM-SLNs are expected to become a safe and effective nanocarrier for the oral delivery of TFDM.

Efecto de la intensidad de diodos electroluminosos y fotoperiodo en la optimización de la producción de biomasa de Spirulina (Arthrospira)

Biomass (ф) production from Spirulina sp. batch cultures was optimized in laboratory scale photobioreactors (LPB) of 0.2 L, by the effect of X1: intensity of light emitting diodes (LEDs) and X2: photoperiod, between 1.25-41.7 klux and 12/12-24/0 hours of light/dark (L/D) respectively using a central composite rotational design (CCRD) and response surface methodology (RSM). The hydraulic characteristics and ф value from Spirulina batch cultures were also evaluated in a closed-loop channel photobioreactor open to the atmosphere (PB-CLOA) by the effect of the lighting LED of 8.3±1.9 klux and photoperiod of 12/12 and 24/0 h L/D. Two optimal zones of ф in LPB were identified, both with a 21.5 klux LED intensity and photoperiod relationship of 12/2 and 24/0 h L/D, with values of 1.65 and 1.62 ф respectively. The mathematical model which indicated the optimal zones was of 2nd order, which had a high significance (p = 0.000396 < 0.05) achieving a predictive value of R2 = 0.92. In the PB-CLOA, the cultivation of Spirulina sp. with photoperiod of 12/12 h L/D, showed a ф value of 0.72, a more rapid adaptation of λ = 4.62 h, a higher specific growth rate of μmax=0.033 h-1 and reduced time energy consumption of 74.05 h; compared to culture developed with photoperiod 24/0 h L/D. The PB-CLOA hydraulic parameters were: operation volume 2.5 L, flow velocity 0.26 m/s, numbers of Reynolds (Re) 15488, Froude (Fr) 0.60 and Vedernikov (Ved) 0.90.