Central Composite Experimental Design Research Articles

Fermentation of biodiesel-derived crude glycerol to 1,3-propanediol with bio-wastes as support matrices: Polynomial prediction model

Biodiesel production from used cooking oil is sustainable alternative, for bio-energy production. The process generates residual crude glycerol (RCG) as the major energy-rich waste which can be used to produce various bio-based chemicals like 1,3-propanediol (1,3-PDO) through biotechnological interventions. This RCG contains several impurities like methanol, soap, organic materials, salts non-transesterified fatty acids and metals in varied concentrations. These impurities significantly affect yield and productivity of the bio-process due to their marked microbial toxicity. In this work, previously isolated Clostridium butyricum L4 was immobilized on various abundantly available cheap bio-wastes (like rice straw, activated carbon and corn cob) to explore advantages offered and improve tolerance to various feed impurities. Amongst these, shredded rice straw was found most suitable candidate for immobilization and results in maximum improvement in 1,3-PDO production (18.4%) with highest porosity (89.28%), lowest bulk density (194.48Kg/m3), and highest cellular biofilm density (CFU/g-8.4 ×1010) amongst the three matrices. For practical purposes, recyclability was evaluated and it was concluded that even after reusing for five successive cycles the production retained to ∼82.4%. Subsequently, polynomial model was developed using 30 runs central composite factorial design experiments having coefficient of regression (R²) as 0.9520, in order to predict yields under different immobilization conditions for 1,3-PDO production. Plackett-Burman was employed (Accuracy= 99.17%) to screen significant toxic impurities. Based on statistical analysis six impurities were found to be significantly influential on PDO production in adverse manner. With negative coefficient of estimate (COE) varying in decreasing order: Linoleic acid >Oleic acid >Stearic acid >NaCl>K2SO4 >KCl. The study illustrates practical application for repurposing waste glycerol generated from biodiesel plants, thus developing improved agnostic process along with yield production models.

Design space determination to optimize DNA complexation and full capsid formation in transient rAAV manufacturing.

Recombinant adeno-associated virus (rAAV) vectors are a promising platform for in vivo gene therapies. However, cost-effective, well-characterized processes necessary to manufacture rAAV therapeutics are challenging to develop without an understanding of how process parameters (PPs) affect rAAV product quality attributes (PQAs). In this work, a central composite orthogonal experimental design was employed to examine the influence of four PPs for transient transfection complex formation (polyethylenimine:DNA [PEI:DNA] ratio, total DNA/cell, cocktail volume, and incubation time) on three rAAV PQAs related to capsid content (vector genome titer, vector genome:capsid particle ratio, and two-dimensional vector genome titer ratio). A regression model was established for each PQA using partial least squares, and a design space (DS) was defined in which Monte Carlo simulations predicted < 1% probability of failure (POF) to meet predetermined PQA specifications. Of the three PQAs, viral genome titer was most strongly correlated with changes in complexation PPs. The DS and acceptable PP ranges were largest when incubation time and cocktail volume were kept at mid-high setpoints, and PEI:DNA ratio and total DNA/cell were at low-mid setpoints. Verification experiments confirmed model predictive capability, and this work establishes a framework for studying other rAAV PPs and their relationship to PQAs.

HiSorb sorptive extraction for determining salivary short chain fatty acids and hydroxy acids in heart failure patients

Variations in salivary short-chain fatty acids and hydroxy acids (e.g., lactic acid, and 3-hydroxybutyric acid) levels have been suggested to reflect the dysbiosis of human gut microbiota, which represents an additional factor involved in the onset of heart failure (HF) disease. The physical–chemical properties of these metabolites combined with the complex composition of biological matrices mean that sample pre-treatment procedures are almost unavoidable. This work describes a reliable, simple, and organic solvent free protocol for determining short-chain fatty acids and hydroxy acids in stimulated saliva samples collected from heart failure, obese, and hypertensive patients. The procedure is based on in-situ pentafluorobenzyl bromide (PFB-Br) derivatization and HiSorb sorptive extraction coupled to thermal desorption and gas chromatography-tandem mass spectrometry. The HiSorb extraction device is completely compatible with aqueous matrices, thus saving on time and materials associated with organic solvent-extraction methods. A Central Composite Face-Centred experimental design was used for the optimization of the molar ratio between PFB-Br and target analytes, the derivatization temperature, and the reaction time which were 100, 60 °C, and 180 min, respectively. Detection limits in the range 0.1–100 µM were reached using a small amount of saliva (20 µL). The use of sodium acetate-1-13C as an internal standard improved the intra- and inter-day precision of the method which ranged from 10 to 23%. The optimized protocol was successfully applied for what we believe is the first time to evaluate the salivary levels of short chain fatty acids and hydroxy acids in saliva samples of four groups of patients: i) patients admitted to hospital with acute HF symptoms, ii) patients with chronic HF symptoms, iii) patients without HF symptoms but with obesity, and iv) patients without HF symptoms but with hypertension. The first group of patients showed significantly higher levels of salivary acetic acid and lactic acid at hospital admission as well as the lowest values of hexanoic acid and heptanoic acid. Moreover, the significant high levels of acetic acid, propionic acid, and butyric acid observed in HF respect to the other patients suggest the potential link between oral bacteria and gut dysbiosis.

Alternative Utilization of Pennisetum purpureum × Pennisetum americanum: Press Cake Conversion to Biobutanol

Conversion of Pennisetum purpureum × Pennisetum americanum (Napier Pak Chong1) press cake into biobutanol using Clostridium beijerinckii TISTR 1461 was proposed as an alternative to combustion in this study. The optimum conditions for biobutanol fermentation were determined using a full factorial design and a central composite design of experiment. The studied factors were initial pHs (5.50–6.50) and sugar concentrations (40–60 g/L), while butanol yield (g/g reducing sugar utilized) was specified as the optimization response. The results showed that the suitable enzyme loading of alkali-pretreated press cake (at 3% w/w NaOH, 10% substrate loading, boiling at 90 °C, with a reaction time of 1 h) was 10 FPU/g biomass, which provided a glucose yield of 345 mg/g pretreated press cake. The optimized pH and reducing sugar concentration were 6.08 and 43 g/L, respectively. At these conditions, the maximum butanol yield from the hydrolysate of NaOH-pretreated press cake was 0.135 g/g reducing sugar utilized (0.30 g/g glucose utilized). Apart from the possibility of generating much less pollution, it was estimated that using the same amount of press cake, butanol production could possibly have a value comparable to that obtained from combustion for electricity production. A new concept for overall Napier Pak Chong1 grass utilization was also presented.

Antioxidant Potential of Spray- and Freeze-Dried Extract from Oregano Processing Wastes, Using an Optimized Ultrasound-Assisted Method.

Origanum vulgare is recognized worldwide for its numerous applications, in the food industry and beyond. However, the extraction of its essential oils generates a significant amount of waste. The aim of this research was to achieve the valorization of solid waste from oregano hydro-distillation, by (i) optimizing the ultrasound extraction of antioxidants, (ii) evaluating the effect of spray and freeze drying on the extract's physicochemical properties, and (iii) characterizing the obtained powder by its antioxidant capacity. A central composite design of experiments was used to optimize the sample/solvent ratio, ethanol/water ratio, and extraction time. The extract was analyzed for its antioxidant potential by determining the percentage of DPPH inhibition, FRAP, and total phenolic content (TPC). The GAB model best fit the data for the moisture sorption isotherm of the resulting powder. The antioxidant activity of the powders was tested in a ground-beef food system. The TPC was maximized at times longer than 58 min, a sample/solvent ratio between 0.058 and 0.078, and a ratio of ethanol/water around 1. Neither drying method significantly affected the antioxidant properties of the extract, even though the resulting powders from each showed a different morphology (determined using SEM). Encapsulation with maltodextrin protected the spray-dried extract during a 6-month storage period. Powders from both drying methods equally retarded lipid oxidation, and were comparable to the synthetic antioxidant BHT. It is concluded that oregano processing waste is a potent source of antioxidants, and that its dried extract, via an ultrasound-assisted process, can potentially be used as a natural alternative to synthetic antioxidants.

Factorial Mixture Design for Properties Optimization and Modeling of Concrete Composites Incorporated with Acetates as Admixtures

Nowadays, admixtures are used with the aim to provide strength and durability to concrete with less water use. New and low-cost admixtures gained a large amount of consideration to mitigate the problems associated with concrete’s durability and service life without upsetting its strength properties. The current work investigates the effect of three types of acetates on the workability, density, and compressive strength of concrete, which is used in structures of the Iraqi ports that suffer from corrosion damages and deterioration owing to the aggressive marine environments. Potassium acetate (KA), calcium acetate (CaA), and ethyl acetate (EA) are incorporated with different doses (1.38–5.6 wt.% of cement) in concrete mixtures using different water/cement ratios (0.48–0.54) based on an espoused central composite experimental design. The experimental results confirmed that the average workability increased with increasing the acetate dose, particularly with CaA. The density and compressive strength of 28 days of water-cured mixtures increased with increasing acetate dose following the order: Ca &gt; K &gt; Ethyl acetate and decreased with increasing w/c ratio. The high rise in compressive strength and workability linked to control mixtures was 30.8% and 77.3% as well as 15.7% and 64.3% for the mixtures incorporated with 5.6 wt.% CaA and KA, respectively. While it was 14.2% and 58.3% for the mixtures incorporated with 3.5 wt.% EA. RSM was employed to optimize and model the design and hardened properties of concrete mixtures. ANOVA results predicted the same trend, which was obtained from the experimental results. The mathematical models were valued with high-regression coefficients. The highest compressive strength of 42.68 MPa has been achieved for a concrete mixture of 0.48 w/c ratio by the incorporation of 5.1 wt.% CaA through a model with R2 96.97%. The relatively low-cost acetate admixtures, particularly CaA, seemed promising for the fabrication of concrete with outstanding properties.

QbD Approach for Analysis of Tirzepatide in its Bulk and Marketed Formulation by Stability Indicating RP-HPLC

The core intentions of the stated work has been to create and validate a simple, sensitive, specific, precise and cost-effective RP-HPLC method with good performance for the investigation of tirzepatide in API powder and its marketed formulation. HPLC system (WATERS) equipped with DAD detection system was used to develop the current system. The procedure conditions of BDS C18 (150 x 4.6 mm,5 m), 0.01N KH2PO4: Acetonitrile in the ratio of 41:59 (% v/v), a flow of 0.9 mL/min, and a temperature of 31°C were successfully optimized by central composite design of QbD experiments. The optimized wavelength selected was 250 nm. RT of tirzepatide was observed to be 2.841 minutes with good system suitability. The ICH Q2(R1) standards functioned as a validation for the planned action strategy. Linearity was observed for 5 to 30 μg/mL concentration series of tirzepatide with R2 of 0.999. The %RSD results of both precisions were found in the range of 0.40 to 0.41.% recovery of Tirzepatide in spiked samples was assessed to be 99.89%. The LoD and LoQ of tirzepatide were calculated to be 0.05 and 0.14 μg/mL, respectively. The results assured that the established procedure was simple, sensitive, specific, accurate and costeffective. Exploration of tirzepatide under a diversity of FD conditions represents the stability representing the quality of the established HPLC procedure. Hence, the anticipated process has significant credit in the pharmaceutical segment.

Development of invaethosomes and invaflexosomes for dermal delivery of clotrimazole: optimization, characterization and antifungal activity

The objective of this study was to develop novel invaethosomes (I-ETS) and invaflexosomes (I-FXS) to enhance the dermal delivery of clotrimazole (CZ). Twenty model CZ-loaded I-ETS and I-FXS formulations were created according to a face-centered central composite experimental design. CZ-loaded vesicle formulations containing a constant concentration of 0.025% w/v CZ and various amounts of ethanol, d-limonene, and polysorbate 20 as penetration enhancers were prepared using the thin film hydration method. The physicochemical characteristics, skin permeability, and antifungal activity were characterized. The skin permeability of the experimental CZ-loaded I-ETS/I-FXS was significantly higher than that of conventional ethosomes, flexosomes, and the commercial product (1% w/w CZ cream). The mechanism of action was confirmed to be skin penetration of low ethanol base vesicles through the disruption of the skin microstructure. The optimal I-ETS in vitro antifungal activity against C. albicans differed significantly from that of ETS and the commercial cream (control). The response surface methodology predicted by Design Expert® was helpful in understanding the complicated relationship between the causal factors and the response variables of the 0.025% w/v CZ-loaded I-ETS/I-FXS formulation. Based on the available information, double vesicles seem to be promising versatile carriers for dermal drug delivery of CZ.

Experimental Study of Surface Roughness of Pine Wood by High-Speed Milling

The surface roughness of wood has a great influence on its performance and is a very important indicator in processing and manufacturing. In this paper, we use the central composite design experiment (CCD experiment) and artificial neural network (ANN) model to study the changing pattern of surface roughness during the high-speed milling process of pine wood. In the CCD experiments, the spindle speed, feed speed, and depth of cut are used as the influencing factors, and the surface roughness is used as the index to analyze the variation law and fit the surface roughness parameter equation. By measuring the chip size in each group in the CCD experiment, the ANN model is used to predict the surface roughness under this machining parameter by measuring the chip size in each test group. The experimental results showed that the mean error of the surface roughness prediction values in the CCD experiment (12.2%) was larger than that of the ANN model (7.8%), and the mean squared error (MSE) of the ANN model was 0.025, the mean absolute percentage error(MAPE) was 0.01, and the coefficient of determination R2 was 0.95. Compared with the CCD experiment, the ANN model had a higher prediction accuracy. The results of this paper can provide some guidance for the prediction of surface roughness during wood processing.

Optimization of Hempseed-Added Kombucha for Increasing the Antioxidant Capacity, Protein Concentration, and Total Phenolic Content

To enhance the effects of kombucha’s beneficial compounds and their functional properties, studies on kombucha fermentation using alternatives ingredients are needed. The aim of this study was to formulate and optimize kombucha using hempseed as a high antioxidant, phenolic compound, and protein contributor. An experimental central composite design (CCD) with response surface methodology (RSM) was used for maximizing the antioxidant capacity (AC), total phenolic content (TPC), and protein concentrations (PC) of this product. The optimized infusion concentrations were observed at 0.017% of hempseeds and 0.00046% of black tea leaves. AC was determined by the DPPH+ assay in microplate. TPC was determined in microplate using the Folin–Ciocalteu method. PC was determined by Peterson’s modification of the micro-Lowry method. The optimized kombucha results were 0.134 ± 0.002 mg Trolox Eq/mL for AC, 0.473 ± 0.027 mg GA Eq/mL for TPC, and 6.535 ± 0.477 μg/mL of PC. RSM can be developed to optimize the formulation of kombuchas to increase the amounts of desirables compounds. This study demonstrated that hempseeds added to kombucha have a higher antioxidant capacity, total phenolic content, and protein concentration than traditional kombucha.

Poly(tetrahydrofuran)-based fabric phase sorptive extraction combined with HPLC-UV for the determination of antihistamines in human urine

Herein, a poly(tetrahydrofuran)-based fabric phase sorptive extraction (FPSE) membrane was utilized for the isolation and determination of three antihistamine drugs (carbinoxamine, chlorpheniramine, and diphenhydramine) in human urine followed by HPLC-UV analysis. Among other membranes tested, the sol–gel poly(tetrahydrofuran) sorbent coated FPSE membrane was found to be more suitable for extracting the selected drugs. Based on their engineered affinity, the fabricated membranes are highly permeable that allows the extraction of biological samples with no previous pretreatment. The experimental parameters were systematically investigated and optimized using a central composite design of experiment and one-factor-at-a-time approaches. The proposed analytical scheme was validated in terms of linearity (0.10 – 5.0 μg mL−1), selectivity, limit of detection (0.03 μg mL−1), limit of quantitation (0.10 μg mL−1), precision (<12.7 % in all circumstances), and accuracy (% relative recovery: 88.1 – 113.7%). The membranes were reusable for at least 15 extractions with a set criterion of a 10% deviation of the initial performance. The final protocol was efficiently applied for the determination of selected antihistamines in authentic human urine after oral administration of chlorpheniramine and diphenhydramine-containing tablet and syrup, respectively.

A powdered mix of cape gooseberry-based pulp, seed, and peel: Optimization of formulation and spray-drying process

BACKGROUND: Cape gooseberry (CG) is a fruit with nutritional and sensory attributes that generate significant consumer interest. Consumption patterns of this fruit must be in line with the diversification of its value-added products to be offered to new markets. OBJECTIVE: The research aim was to optimize the encapsulants formulation and the spray-drying (SD) process for developing of a powdered mix (PMCG) of CG based pulp, seed and peel, using the response surface methodology (RSM). METHODS: A RSM was used, with a face-centered central composite experimental design (α= 1). The independent variables (IV) were gum arabic (GA) (1 – 3% w/w), maltodextrin (MD) (11,5 – 13,5% w/w), air inlet temperature (AIT) (130 – 160 °C), air outlet temperature (AOT) (75 – 85 °C), and atomizer disc speed (ADS) (18000 – 22000 rpm). The dependent variables (DV) of the PMCG were moisture, solubility, hygroscopicity, wettability (We), color coordinates L* and b*, total phenols (TP), antioxidant capacity, and yield. RESULTS: The experimental optimization presented a desirability of 68.0%, with GA and MD levels in the PMCG of 2.2 and 10.1% p/p, respectively, and process conditions of AIT = 160 °C, AOT = 77.8 °C and ADS = 21450 rpm. The IV with the most significant effect on the DV was the MD. It was observed that the increase in MD decreases the PMCG moisture content, hygroscopicity, and the content of bioactive compounds, but increases the solubility and the values of L* and b*. The SD process was an effective technology that allowed obtaining PMCG with excellent quality attributes. CONCLUSIONS: In the process, greater use was made of the structure of the CG (pulp, seed, and peel), which gave high CG solids to the PMCG obtained and allowed more effective use of the fruit and higher economic viability in the SD process.

Identification of endogenous and exogenous semicarbazide (SEM) in crustacea aquatic products using compound-specific nitrogen stable isotope ratio analysis (NSIRA)

Endogenous SEM (SEMend) naturally occurs in crustacea aquatic products, it confuses the legal verdict of exogenous SEM (SEMex) degraded by antibiotic nitrofurazone abuse. In the present study, compound-specific gas phase chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) analysis coupled with a two-step pre-column derivatization was developed for determining the nitrogen stable ratio (δ15N) of SEM in shrimp and crab. The optimal derivatization and solid phase extraction (SPE) condition of SEM were screened by Plackett-Burman design and central composite design (CCD) experiment. The nitrogen isotope ratio analysis (NSIRA) of SEM in two types of crustaceans proved that its δ15N values significantly decreased from 7.0‰ to 2.0‰ once nitrofurazone being used. Analytical results found that the δ15N value of SEMex in vivo was consistent its nitrofurazone precursor but the value of SEMend was dependent on N-containing components (e.g., tissue protein), ANOVA showed significant difference between two types of SEM (p < 0.05). Based on the δ15N variations between SEM itself and its nitrofurazone precursor, tissue protein of crustaceans, the percentages of SEMex and SEMend can be calculated for its source apportionment in vivo. The limit of detection of SEM is down to 0.21 μg kg−1 and 0.54 μg kg−1, and the identification lower limit of SEMex are accurate at 6.27% and 0% for two types of crustaceans. The strategy first realized the independent determination of SEMex and SEMend in crustacea aquatic products, which explained that high-level SEM in crustaceans can’t as the legal verdict of nitrofurazone abuse in aquaculture.

Pyro-gasification of Rice Husk to Bio-fuel

Rice husk is a promising candidate of sustainable biomass-based renewable energy source with a gross caloric content of around 19.73 MJ/kg. As an efficient thermo-conversion process, pyro-gasification has the potential to convert biomass into oil and gas fuels. However, the bio-oil and gas yields are strongly dependent on the pyro-gasification operating parameters. This study employed response surface methodology (RSM) based on central composite design (CCD) experiment to determine the optimum conditions for pyro-gasification of rice-husk. Three selected most influencing operating parameters, namely feed mass (g), nitrogen flow (mL/min), and reactor temperature (°C) were optimized through 16 individual experimental runs for their possible synergistic effects. The results show excellent model fitting criteria (R2 &gt; 0.9 and R2-adj &gt; 0.85) for bio-oil and gas product responses that proves the suitability of RSM based on CCD experiment for rice-husk pyro-gasification study. The optimized optimum condition for rice-husk pyro-gasification process was at 897 g of feed mass, 1.97 mL/min of N2 gas flowrate, and 593 °C of reaction temperature. These conditions allow the achievement of estimated bio-oil and gas product yield of 47.78% and 11.41%, respectively. The composition analysis revealed that the main component of bio-oil was C15 (unsaturated), whereas the gas products were C3–C4 . This study suggests that rice-husk pyro-gasification is capable to achieve maximum yield of bio-oil and gas products with low char generation.

Simple and rapid synthesis of magnetic kiwifruit for the removal of sitagliptin and fampridine residues from aqueous media using HPLC method: optimization via central composite experimental design

Simple and rapid synthesis of magnetic kiwifruit for the removal of sitagliptin and fampridine residues from aqueous media using HPLC method: optimization via central composite experimental design

Stability indicating HPLC method development and validation of Fostemsavir in bulk and marketed formulations by implementing QbD approach

Background: Achieving a predictable degree of quality with intended and planned specifications is known as "quality by design." QbD (Quality-by-Design) is an alternative to conventional method development that places more attention on identifying and mitigating potential risks. Component of the Quality-by-Design methodology involves conducting a series of experiments to learn how various factors, including the dependant variables, affect the answers of interest. Here, we use a QbD (Quality-by-Design) loom to detail the creation and verification of a stability-indicating high-performance liquid chromatography (HPLC) method for Fostemsavir in both bulk and finished-goods forms.&#x0D; Results:&#x0D; In this work, we present a workable experimental design for optimising the RP-HPLC separation technique by identifying the optimum mobile phase concentration and flow rate. Below are the ideal chromatographic conditions as calculated by Design Expert version 13.0: Mobile phase: 80 parts acetonitrile to 20 parts formic acid (v/v), flow rate: 0.8 millilitres per minute, retention time: 3.24 minutes, column dimensions: GIST C18 (250 mm × 4.6 mm × 5.0 μm).&#x0D; Here we propose a practical experimental layout for determining the optimal mobile phase concentration and flow rate for the RP-HPLC separation technique. Using Design Expert version 13.0, the optimum chromatographic conditions were determined to be as follows: Shim-pack GIST C18 (250 mm 4.6 mm, 5.0 μ), mobile phase acetonitrile to 1% formic acid (80:20, v/v), flow rate 0.8 ml/min, and retention period 3.24 min.&#x0D; At a detection wavelength of 266 nm, it was discovered that the devised technique was linear over a concentration range of 50-90 μg/ml (r2 = 0.997). Test parameters for the system's appropriateness were determined to be 1.124 for the tailing factor and 9480 for the theoretical plates. Intraday RSD was found to range from 0.70 to 0.94, whereas interday RSD was found to range from 0.55 to 0.95 percent. Values for robustness were under 2%. The solution stability % RSD was calculated to be 0.83. The result of the assay was 100.05 percent. The created methodologies were used to studies of forced degradation, and the stressed materials were analysed. The parameters used to validate the procedure fell within the acceptable range recommended by ICH.&#x0D; Conclusion: Using Design Expert 13.0, we created a central composite design experiment that illustrates the relationships between mobile phase and flow rate across three levels, with retention duration, tailing factor, as well as theoretical plates as the responses of interest. By this work, we gain insight into the variables that affect chromatographic separation and strengthen our conviction that the HPLC method we've devised will serve our needs. Quantitative method development was applied to improve comprehension of multi-tiered method variables.

Rapid and inexpensive voltammetric detection of ochratoxin A in wheat matrices

Produced as toxic metabolites by fungi, mycotoxins, such as ochratoxin A (OTA), contaminate grain and animal feed and cause great economic losses. Herein, we report the fabrication of an electrochemical sensor consisting of an inexpensive and label-free carbon black-graphite paste electrode (CB-G-CPE), which was fully optimized to detect OTA in durum wheat matrices using differential pulse voltammetry (DPV). The effect of carbon paste composition, electrolyte pH and DPV parameters were studied to determine the optimum conditions for the electroanalytical determination of OTA. Full factorial and central composite experimental designs (FFD and CCD) were used to optimize DPV parameters, namely pulse width, pulse height, step height and step time. The developed electrochemical sensor successfully detected OTA with detection and quantification limits equal to 57.2 nM (0.023 µg mL−1) and 190.6 nM (0.077 µg mL−1), respectively. The accuracy and precision of the presented CB-G-CPE was used to successfully quantify OTA in real wheat matrices. This study presents an inexpensive and user-friendly method with potential applications in grain quality control.

Processing effects on the protein quality and functional properties of cold-pressed pumpkin seed meal

Environmental and food security challenges due to a growing world population may be overcome by using alternative protein sources for the human diet. By-products from edible oil processing industries are potential sources due to their high protein content. Pumpkin seed meals were evaluated regarding proximate composition, in vitro protein digestibility (IVPD), amino acid profile and score, and antinutritional factors. Conventional thermal processing, microwave, and ultrasound treatments impact on samples’ nutritional quality were assessed using a central composite experimental design. Raw pumpkin seed meal presented up to 45% protein content and 86% IVPD. Processing increased IVPD up to 96%, with optimized conditions of 87.8 °C, pH8.0, and 37 min, for all processes. Lysine was the only limiting amino acid for raw and processed samples. Phytic acid decreased by 31%, while trypsin inhibitory activity was reduced by 84%. Pumpkin seed by-product is a promising high-quality plant protein source for food formulations.

Degradation of carbamazepine by the photo-Fenton process. Approach towards the elucidation of degradation by-products

Carbamazepine (CBZ) is a pollutant of emerging concern because of its adverse effects associated. This work deals with the degradation of 1 mg L-1 of CBZ by the photo-Fenton process in water to discern the potential of this advanced oxidation process for the elimination of this persistent pollutant. For this purpose, the operating conditions were optimized using a central composite design of experiments, testing the influence of ferrous ion (Fe2+) and hydrogen peroxide (H2O2) concentrations on the degradation of CBZ. As a result, 96.4% of CBZ removal was obtained under optimal operating conditions (0.750 mg L-1 and 0.2 mg L-1 of H2O2 and Fe2+, respectively). In addition, the effect of the initial concentration of the target drug on the oxidation capacity of the photo-Fenton process was assessed by analyzing the removal kinetic constant. This value was achieved through a pseudo-first order model and resulted to be 0.0182 µmol L-1 min−1. Additionally, the degradation of CBZ in surface water was evaluated, obtaining an elimination of 74.4%. Finally, the identification of some CBZ by-products was carried out, being one of them purified and elucidated by means of the nuclear magnetic resonance technique and mass spectrometry. The referred degradation by-product was identified for the first time as 2,2′-aminodibenzaldehyde. In this regard, the photo-Fenton process is concluded to be able of degrading CBZ in natural surface water.

Optimization of fermentation medium components by response surface methodology (RSM) and artificial neural network hybrid with genetic algorithm (ANN-GA) for lipase production by Burkholderia cenocepacia ST8 using used automotive engine oil as substrate

Bioconversion of used automotive engine oil (UEO) into lipase was conducted via submerged fermentation by Burkholderia cenocepacia ST8, as a strategy for value-added product generation and waste management. Response surface methodology (RSM) and artificial neural network hybrid with genetic algorithm (ANN-GA) were employed to optimize the fermentation medium for enhancing extracellular lipase production by B. cenocepacia ST8. Employing a four-factor-five-level central composite rotatable experimental design (CCRD), a reduced quartic polynomial RSM model and ANN model (4-4-1) trained using Bayesian Regularization were developed to attain the optimized fermentation medium for maximum level of lipase production. The RSM model predicted the following as the optimum media constituents: 2.28% v/v of Tween 80, 2.26% v/v of UEO, 0.79% w/v of nutrient broth, and 1.33% w/v of gum arabic, with an actual lipase yield of 216 U/mL. While, ANN-GA predicted the optimum media constituents to be 3% v/v of Tween 80, 3% v/v of UEO, 0.72% w/v of nutrient broth, and 3.38% w/v of gum arabic, with actual lipase yield of 225 U/mL. In comparison to the unoptimized medium, optimized RSM and ANN-GA systems both demonstrated a 1.6-fold increment in lipase production. Tween 80 and nutrient broth concentrations were the most important variables influencing the lipase production. The findings of this study indicated that the ANN-GA and RSM could be useful for effective optimization of the fermentation medium for enzyme production.