Central Composite Rotatable Design Research Articles

Parametric optimization to establish eco-friendly nanofluid minimum quantity lubrication (NMQL) practice for turning superalloy Inconel 718

Purpose The purpose of this paper, an experimental study, is to investigate the optimal machining parameters for turning of nickel-based superalloy Inconel 718 under eco-friendly nanofluid minimum quantity lubrication (NMQL) environment to minimize cutting tool flank wear (Vb) and machined surface roughness (Ra). Design/methodology/approach The central composite rotatable design approach under response surface methodology (RSM) is adopted to prepare a design of experiments plan for conducting turning experiments. Findings The optimum value of input turning parameters: cutting speed (A), feed rate (B) and depth of cut (C) is found as 79.88 m/min, 0.1 mm/rev and 0.2 mm, respectively, with optimal output response parameters: Vb = 138.633 µm and Ra = 0.462 µm at the desirability level of 0.766. Feed rate: B and cutting speed: A2 are the leading model variables affecting Vb, with a percentage contribution rate of 12.06% and 43.69%, respectively, while cutting speed: A and feed rate: B are the significant factors for Ra, having a percentage contribution of 38.25% and 18.03%, respectively. Results of validation experiments confirm that the error between RSM predicted and experimental observed values for Vb and Ra is 3.28% and 3.75%, respectively, which is less than 5%, thus validating that the formed RSM models have a high degree of conformity with the obtained experimental results. Practical implications The outcomes of this research can be used as a reference machining database for various metal cutting industries to establish eco-friendly NMQL practices during the turning of superalloy Inconel 718 to enhance cutting tool performance and machined surface integrity. Originality/value No study has been communicated till now on the turning of Inconel 718 under NMQL conditions using olive oil blended with multi-walled carbon nanotubes-based nanofluid. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2023-0317/

Physicochemical models applied to a malt healthy-friendly soft drink production

The increasing demand for enzymatically hydrolyzed proteins, easily digestible carbohydrates, and nutritionally enriched beverages has propelled the popularity of malt-based health-friendly soft drinks (MHFSDs). Ensuring consistent quality, safety, and flavor underscores the significance of comprehending MHFSDs' physicochemical attributes. Through the application of central composite rotational design (CCRD), the impact of light and dark malt extract concentrations (LME and DME) and added sugar (AS) on these attributes was assessed. CCRD facilitated the creation of predictive mathematical models for pivotal physicochemical properties in MHFSDs, including pH, acidity, reducing sugar, total sugar, and color. These properties exert substantial influence on MHFSDs' overall quality and sensory characteristics. The reliability in understanding MHFSDs' physicochemical attributes is confirmed by high determination coefficients (pH=0.98, acidity=0.87, reducing sugar=1.00, total sugar=0.98, luminosity dimension=0.98, red-green dimension=0.76, yellow-blue dimension=0.64). The integration of CCRD and mathematical models provides a systematic, data-oriented strategy for formulating health-friendly soft drinks that fulfill desired benchmarks, presenting consumers with a more health-conscious and enjoyable beverage alternative.

The potential use of supercritical carbon dioxide in sugarcane juice processing

Sugarcane juice is a nutritious and energetic drink. For its processing, the use of supercritical carbon dioxide (SC-CO2) technology as an intervention potentially capable of rendering a high quality product can be considered. This study evaluated the combined effect of SC-CO2 and mild temperatures, primarily aiming for the reduction of endogenous microorganisms and enzymes in sugarcane juice (pH~5.5). Pressures (P) ranging from 74 to 351 bar, temperatures (T) between 33 and 67 °C, and holding times (t) between 20 and 70 min were tested in a central composite rotational design. Seventeen trials were performed, comprising three replicates at the central points. Counts of aerobic mesophiles, molds and yeasts, lactic acid bacteria and coliforms at 45 °C, determination of polyphenol oxidase (PPO) and peroxidase (POD) activities, and measurement of color parameters in freshly extracted and processed juice’s samples were carried out. The pH of fresh and processed juice varied between 4.6 and 6.0, and between 4.6 and 6.3, respectively. The number of decimal reductions achieved in mesophiles, molds and yeasts, lactic acid bacteria and coliforms varied between 0.1 and 3.9, 2.1 and 4.1, 0.0 and 2.1, and 0.3 to 2.5, respectively. The percentages of PPO reduction ranged from 3.51% to 64.18%. Regarding the POD, reductions between 0.27% and 41.42% were obtained. Color variations between fresh and processed samples varied between 2.0 and 12.3. As for mesophiles, molds and yeasts reduction, and soluble solids variation, none of the variables or their interactions were significant. In terms of polyphenol oxidase (PPO) reduction, only t was significant; however, T, t, and the interaction between them significantly affected the peroxidase (POD) reduction. In regards to pH variation, P, and the interaction between T and t were significant. P, T, t, and the interaction between T and t played a significant effect on color. The combination of mild temperatures and SC-CO2 can be potentially used for cane juice preservation.

Investigation of the geometry of an electrochemical reactor in order to minimize the operational energy cost in the treatment of cosmetic effluents

Low biodegradability and high toxicity are common characteristics of cosmetic effluent. They have stimulated the application, development, and improvement of advanced technologies, such as electrocoagulation (EC). In this sense, this study aimed to optimize the treatment conditions of operational parameters considering the theoretical energetic operational cost of the treatment of cosmetic effluents through a new design of a cylindrical electrochemical reactor in continuous upward flow (CER-CUF). The effects of hydraulic retention time (HRT), electrical current density (j), and electrical conductivity on COD removal, turbidity, and residual Al concentration were investigated using a Central Composite Rotational Design (CCRD). The COD and turbidity removal efficiencies were 61.96 % and 44.71 %, respectively, with a total operating cost of 0.258 US$ m−3 to treat the effluent cosmetic under optimized conditions (HRT:5 min/j: 5 mA cm−2 and EC:2000.00 μS cm−1) in CER-CUF. These results contribute to advancing of knowledge about electrocoagulation technology and the possibility of full-scale application, in addition to encouraging the use of CER-CUF for treating effluents from the cosmetic industry.

Optimizing the Antimicrobial Activity of Sodium Hypochlorite (NaClO) over Exposure Time for the Control of Salmonella spp. In Vitro.

Fish is a nutritionally rich product; however, it is easily contaminated by pathogenic microorganisms, such as Salmonella spp. Therefore, this study aimed to identify the best concentration of sodium hypochlorite (NaClO), exposure time, and water temperature that allow the most effective antimicrobial effect on the viable population of Salmonella spp. Thus, Salmonella Enteritidis ATCC 13076 and Salmonella Schwarzengrund were exposed to different time frames, ranging from 5 min to 38.5 min, temperatures between 5 and 38.5 °C, and NaClO concentrations ranging from 0.36 to 6.36 ppm, through a central composite rotational design experiment (CCRD). The results demonstrated that the ATCC strain exhibited a quadratic response to sodium hypochlorite when combined with exposure time, indicating that initial contact would already be sufficient for the compound's action to inhibit the growth of the mentioned bacteria. However, for S. Schwarzengrund (isolated directly from fish cultivated in aquaculture), both NaClO concentration and exposure time significantly influenced inactivation, following a linear pattern. This suggests that increasing the exposure time of NaClO could be an alternative to enhance Salmonella elimination rates in fish slaughterhouses. Thus, the analysis indicates that the Salmonella spp. strains used in in vitro experiments were sensitive to concentrations equal to or greater than the recommended ones, requiring a longer exposure time combined with the recommended NaClO concentration in the case of isolates from aquaculture.

Optimization and kinetics study for the conversion of furfuryl alcohol towards ethyl levulinate using sulfonic acid functionalized catalyst

Abstract In the present work, furfuryl alcohol (FAL) alcoholysis towards ethyl levulinate (EL) was studied over a mesoporous SO3H-SBA-15 catalyst. The effect of various operating parameters i.e., temperature, catalyst dose, furfuryl alcohol amount, and time was studied and optimized via robust Response Surface Methodology through central composite rotatable designs (CCRD) method on the conversion of FAL to EL. According to Response Surface Methodology, under optimum reaction conditions viz. temperature 110 °C, catalyst dose 0.42 g, time 3 h, and FAL amount of 1.46 g, maximum EL yield (95 %) was recorded. Further, the effect of reaction parameters on the kinetics of the said reaction was also examined, suggesting the second-order kinetic concerning all operating parameters. Eventually, the reusability of the catalyst is evident in a decrease of almost 40 % yield towards EL in the fourth cycle.

Fabrication of TPGS decorated Etravirine loaded lipidic nanocarriers as a neoteric oral bioavailability enhancer for lymphatic targeting

Etravirine (ERVN) is a potential NNRTI (non-nucleoside reverse transcriptase inhibitor) in treating HIV infection. It possesses extremely low oral bioavailability. The present research aims to optimize the formulation and characterization of TPGS-enriched ERVN-loaded lipid-based nanocarriers (NLCs) for HIV-infected patients. The formulation, ERVN–TPGS–NLCs, was optimized by central composite rotational design using a modified-solvent emulsification process. Various characterization parameters of NLCs were evaluated, including globule size of 121.56 ± 2.174 nm, PDI of 0.172 ± 0.042, the zeta potential of − 7.32 ± 0.021 mV, %EE of 94.42 ± 8.65% of ERVN and %DL was 8.94 ± 0.759% of ERVN and spherical shape was revealed by TEM. PXRD was also performed to identify the crystallinity of the sample. In-vitro drug release showed % a cumulative drug release of 83.72 ± 8.35% at pH 1.2 and 90.61 ± 9.11% at pH 6.8, respectively, whereas the % cumulative drug release from drug suspension (ERVN-S) was found to be 21.13 ± 2.01% at pH 1.2 and 24.84 ± 2.51 at pH 6.8 at the end of 48 h. Further, the intestinal permeation study and confocal microscope showed approximately three-fold and two-fold increased permeation in ERVN–TPGS–NLCs and ERVN-NLCs across the gut sac compared to ERVN-S. Hemolysis compatibility and lipolysis studies were performed to predict the in-vivo fate of the formulation. The pharmacokinetic study revealed a 3.13-fold increment in the relative bioavailability, which agrees with the ex-vivo studies, and lymphatic uptake was validated by using cycloheximide along with designed formulation, which showed the impact of lymphatic uptake in AUC. This study ensures that ERVN–TPGS–NLCs take lymphatic uptake to minimize the first-pass metabolism followed by improved oral bioavailability of ERVN. Thus, the enhanced bioavailability of ERVN can reduce the high dose of ERVN to minimize the adverse effects related to dose-related burden.Graphical abstract

Efeito do ultrassom no amaciamento do músculo Biceps femoris em bovinos Nelore

ABSTRACT: The effect of ultrasound on Biceps femoris muscle tenderness was investigated using a 22 Central Composite Rotatable Design (CCRD) with triplicates at the central point. We evaluated the following independent variables: ultrasound intensity ranging from 11.30 to 33.90 W cm-2 and exposure time between 35 and 205 s. The ultrasound bath’s frequency (80 kHz) and temperature (10 ºC) were the fixed ones. To validate the model, the muscle was treated at the CCRD’s optimized condition (80 kHz, 22.60 W cm-2, 120 s, 10 ºC) evaluated, and compared with the muscle control sample (non-treated). A 22% shear force reduction was observed compared to the control sample (no ultrasound treatment) after 144 h, and stored at 5 ºC. Moreover, a sarcoplasmic calcium concentration increase was noted for ultrasound-treated muscle, probably activating the calpain enzyme system. In contrast, no significant influence (P > 0.05) was observed for pH, color index, lipid oxidation, water holding capacity, and drip loss by ultrasound treatment at the optimized conditions. Therefore, ultrasound application is promising and suitable for improving muscle tenderness without losing meat quality. This study highlighted the ultrasound effect on the tenderness of a less studied muscle (Biceps femoris) by combining short ultrasound exposure (120 s) and an 80 kHz frequency.

Effect of Blending Ratio and Extrusion Operating Conditions on Nutritional Quality and Functional and Sensory Acceptability of Teff‐Bulla‐Based Complementary Food: A Response Surface Methodology Approach

The purpose of this study was to identify possible locally accessible cereals, tubers, and legumes for use in the extrusion of teff, bulla, and haricot beans to prepare inexpensive supplemental foods. This study used central composite rotatable design (CCRD) to assess the effects of specific processing parameters on response variables such as proximate composition and physical, functional, and sensory qualities of produced complementary food. The processing parameters included haricot bean blending ratios (BR) (10–30%), feed moisture content (FMC) (15–21%), and barrel temperature (BT) (120–160°C). The proximate composition of the complementary food ranged from 9.25 to 12.36% moisture content, 7.82 to 14.04% protein, 2.1 to 3.28% ash, 1.13 to 3.93% fiber, 1.17 to 3.12% fat, 65.40 to 78.25% carbohydrate, and 338.42 to 354.86 kcal/100 g energy. The predominant minerals and antinutritional factors ranged from 2.40 to 10.37 mg/100 g, 58.70 to 146.26 mg/100 g, 0.8 to 4.74 mg/100 g, 113.21 to 325.00 mg/100 g, and 16.54 to 44.62 mg/100 g for Fe, Ca, Zn, phytate, and tannin, respectively. The blending ratio and extrusion parameters demonstrated significant (p < 0.05) linear, quadratic, and interaction impacts on the physical and functional responses, according to analysis of variance (ANOVA). Mothers and caregivers largely approved all the trial porridges. The best blending and extrusion parameters, according to numerical optimization, were a BR of 28.2837%, FMC of 15.0007%, and BT of 120.001°C. The predicted responses for optimization were water solubility index (WSI) (32.4462 g/g), water absorption index (WAI) (3.69849%), viscosity (2016.47cP), protein (14.046%), and energy (348.034 kcal/100 g) with a desirability value of 0.856. This research leads us to believe that producing complementary meals with excellent nutritional value for developing nations may be achieved by evidence‐based selection of locally accessible plant‐based components.

Fibra alimentar, polifenóis e aceitabilidade sensorial e tecnológica em pães fatiados elaborados com farinha de casca de manga

Abstract The use of mango peel, an agro-industrial byproduct rich in bioactive compounds, was the subject of this study, seeking an innovative application in the manufacture of sliced bread. This process is proposed as a way to create a nutritious and healthy food, rich in dietary fiber and total polyphenols. Mango peel flour of the Kent variety was obtained by drying, grinding, and sieving. An experimental design through the Response Surface Methodology (RSM) with a central composite rotatable design, was used to evaluate the impact of mango peel flour (5% to15%) and ascorbic acid (20 to100 ppm) in the bread formulation. Technological, sensory evaluations, and determinations of polyphenols and dietary fiber were carried out, using standard methods. The results showed that mango peel flour and ascorbic acid influence the texture of the bread, with formulations of 10% mango peel flour and 60 ppm ascorbic acid obtaining the best sensory ratings in color, appearance, aroma, and texture. The mango peel flour increased the fiber up to 13.25 g/100 g and polyphenols up to 1.187 g AGE/g dry weight (DW) in the sliced bread. These findings suggest that the inclusion of mango peel flour improves the nutritional and sensory quality of bread, showing its potential as a functional ingredient in the food industry.

Mathematical Modelling to Predict Bead Geometry Parameters of MIG Welded Aluminum 6063 Plates

The purpose of this research is to evaluate the effect of various operational parameters like voltage, weld speed, torch angle, nozzle to plate distance (NPD), and wire feed rate on bead geometry of welds on aluminum 6063 plates. This aluminum grade has a wide range of applications, from industrial to home. The bead geometry properties of a fusion weld are essential from a design standpoint because they affect the joint's mechanical strength and dependability throughout its usage. Bead width (BW), depth of penetration (DOP), and height of reinforcement (HOR) are all essential bead parameters, which need to be considered while commenting on bead geometry of a weld. An experiment series was performed with the statistical technique of design of experiments, using the central composite rotatable design (CCRD) method. This resulted in a mathematical model that correlated bead geometry parameters with various input parameters. RSM (Response Surface Methodology) is used for the graphical analysis of the results obtained. The suggested framework aims to optimize the input variables in order to attain the specified bead parameter values.

LIPASE FROM Rhizopus oryzae IMMOBILIZED ON CORN COB POWDER: A NEW APPROACH FOR DIETETIC TRIGLYCERIDE SYNTHESIS IN A FIXED BED REACTOR

This work explores the possibility of using corn cob powder as a carrier for immobilization by physical adsorption of lipase from Rhizopus oryzae used in acidolysis reaction of grape seed oil with capric acid (C10) to synthesize dietary triglycerides (TAGs) formed from medium-long-medium chain (MLM) fatty acids in a fixed bed reactor. First, enzymatic loading was investigated to improve hydrolytic activity and the immobilized biocatalyst was characterized in terms of biochemical parameters and thermal stability. An enzyme load of 30 mg mL-1 was quite adequate, as about 90% of the immobilization yield was achieved. The central composite rotatable design (CCRD) experimental design revealed that, for the immobilized enzyme, the optimal hydrolytic activity was obtained at pH 7.75 and 41 °C. Stirred tank reactions were optimized in CCRD statistical analysis revealing the most desirable conditions for molar ratio of 1:9.36 (oil:acid), 45 °C and 15% biocatalyst, obtaining a maximum ID value of 86.93 ± 2.25%. In a fixed bed reactor, the synthesis showed an average ID of 51.13 ± 0.77, demonstrating the potential of this configuration. It is concluded that corn cob powder as an immobilization carrier is a promising alternative for the enzymatic synthesis of MLM triacylglycerols.

Electrochemical oxidation of methyl blue dye by stainless steel tubes bundle anode

Methyl blue dye was successfully electrochemically oxidised in a flow-through batch circulation process using a stainless-steel tube bundle anode. The experimental design and process optimisation were conducted according to the response surface Methodology with Rotatable Central Composite Design method. The controlled variables in this study were the solution flow rate, applied current, electrolyte concentration, and time. A quadratic mathematical model expressing the removal percentage as a function of the operating variables and their interactions was constructed from the experimental data. The accuracy of the model was confirmed using residual plots and an R2 value of 0.8526. Solution flow rate was found to promote the removal percentage up to 1.5 l/min, the applied current promoted the removal efficiency significantly up to 400 mA, the electrolyte concentration had a positive effect up to 2 M, and the removal efficiency increases generally with time, reaching the equilibrium removal percentage at 67.121 min. The optimum conditions for the target with the highest removal percentage of 91.333% were found to be 1.5 l/min solution flow rate, 400 mA applied current, 2 M electrolyte solution, and 67.121 min.

A low-cost iron mining residue catalyst employed in antibiotic degradation: Parameter optimization, influence of photogenerated species and the identification of main transformation products

The ubiquitous presence of antibiotics in aquatic ecosystems due to their frequent and indiscriminate use has become a major global health concern, leading to high environmental bacteria and resistance gene development. In this context, this study aimed to evaluate the degradation of three antibiotics, ciprofloxacin (CIP), sulfamethoxazole (SMX) and tetracycline (TET), employing a mining residue as the photocatalyst. The mining residue was characterized by the Brunauer-Emmett-Teller (BET), X ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), X ray diffraction (XRD) techniques, and exhibited high iron content (∼70%) predominantly Fe+2. A rotatable central composite design (RCCD) employing catalyst concentrations, H2O2 and pH as variables was applied, resulting in optimal catalyst and H2O2 concentrations of 277.01 mg L−1 and 65.37 mg L−1, respectively, at pH 3.4. These conditions achieved 89% and 83% SMX and CIP degradation rates and the TET concentration at 60 min of treatment was lower than the instrumental LOD, confirming the predominance of catalyst photo-Fenton reactions. When applied to a real effluent sample, 71% and 79% SMX and CIP degradation rates were observed, respectively, while no degradation value changes were noted for TET at 60 min. The main reactive species involved in the antibiotic degradation reactions were HO• for SMX, O2•- and h+ for CIP, and O2•- for TET. In total, 12 antibiotic transformation products (TPs) were identified by LC-QTOF MS. The most frequent TPs observed during antibiotic degradation were formed by hydroxylation, dealkylation, defluorination and hydrolysis of the sulfonamide bond. The investigated mining residue is, therefore, a low-cost and efficient alternative for the photocatalytic degradation of CIP, SMX and TET, contributing to the United Nations Sustainable Development Goals (SDG 6) and follows circular economy principles.

Formulation of jaggery based sesame (Sesamum indicum L.) seed spread using response surface methodology: A novel alternative for consumers

AbstractThe aim of this study was to develop a jaggery based sesame seed spread. A central composite rotatable design (CCRD) was employed with various parameters: roasting temperatures (Y1: 110–170°C), roasting time period (Y2:10–30 min), Hydrogenated vegetable oil (Y3: 3%–7%), and jaggery level (Y4: 4%–20%) to optimize its process. The evaluation of the sesame spread involved analyzing its texture attributes (adhesiveness, cohesiveness, hardness, and viscosity) and its sensory characteristics (taste, color and appearance, spreadability, aroma, and overall acceptability). The results revealed that the roasting temperatures exerted the highest influence among the tested variables, followed by the roasting time period, jaggery content, and hydrogenated vegetable oil. Optimum sesame spread quality attributes were obtained with roasting temperatures (147°C), roasting time period (27.30 min.), hydrogenated vegetable oil (6.20%), and jaggery content (9.50%). The successful incorporation of jaggery for producing a high‐quality sesame spread resulted in a noteworthy improvement in the quality profile of the sesame spread.

Using an economic method to prepare TiO2 from natural ilmenite for photodegradable dye removal

In this work, nanoparticles of ilmenite powder (47 nm) were prepared via ball-milling of natural ilmenite ore to enhance the specific surface area of particles. The photocatalytic activity of magnetically separable ilmenite nanoparticles was investigated in the degradation of methyl orange (MO) and methylene blue (MB). The Band gap of the ilmenite nanoparticles was calculated 3.05 eV. The photodegradation results show that ilmenite nanoparticles completely destruct MO and MB in 40 and 50 min under visible irradiation. In order to choose of optimum values of factors, the leaching process was optimized by applying a “Rotatable Central Composite Design” (CCD) technique. For preparing of required precursor, the grind ilmenite was crushed into small particles by ball milling method. In addition, in order to purifying the titanium slag, reduction process was carried out. Effective Factors on sulfuric acid process as follows leaching time, temperature, acid concentration and solid/liquid (S/L) ratio, were studied.

Optimization of gluten-free bread using RSM (Design Expert) to study its textural and sensory properties

The urgent need for gluten-free bread by Celiac disease patients and gluten-sensitive populations has spawned a new and emerging food industry to provide a substitute bread that is gluten-free. This study aims to provide an effective substitute bread using locally available indigenous crops like Jackfruit Seed and Flour (Artocarpus heterophyllus Lam) and Mapillai Samba Rice Flour (Bridegroom Oryza sativa L) as the key ingredients. Central Composite Rotatable Design of Response Surface Methodology was applied to study the overall comparative acceptability of the gluten-free bread. By adjusting ratios of the three main ingredients, 20 different composite flour formulations without gluten were used to make gluten-free bread. Textural qualities (hardness and springiness), loaf volume, colour value, and sensory quality were studied to find the best combination of the three key components for the creation of gluten-free bread. Such a viable and desirable product will have commercial implications

Environmentally sustainable analytical quality by design aided RP-HPLC method for the estimation of brilliant blue in commercial food samples employing a green-ultrasound-assisted extraction technique

Abstract Brilliant blue FCF (E133) is a commonly employed azo synthetic dye in the food industry owing to its visually appealing color and widespread consumer acceptance. The health risks associated with the excessive use of brilliant blue necessitate prioritizing eco-friendly methods for its quantification. The purpose of this study is to develop and validate an analytical quality by design (AQbD) based eco-friendly high-performance liquid chromatography method adhering to the 12 principles of green chemistry followed by ultrasound-assisted extraction of food samples and confirming them using Fourier transform infrared spectroscopy. Rotatable central composite designs (CCDs) were utilized to optimize the chromatographic parameters. The separation was achieved on a Phenomenex column (Luna C18, 250 mm × 4.6 mm, i.d. 5 μm) employing ethanol and acetate buffer as a mobile phase in the ratio 25:75 (v/v) at a flow rate of 1 mL·min−1 with detection at 626 nm, which resulted in elution of brilliant blue at 2.692 min. The developed method fulfills the predetermined requirements of linearity, accuracy, sensitivity, and reproducibility at the specified working point. The green analytical procedure index, analytical eco scale, and analytical greenness metrics were used for assessing greenness, which yielded the most benign outcomes. In the future, this research could lead to the adoption and enhancement of eco-friendly robust AQbD methodologies for evaluating various food colorants, utilizing green solvents.

Microencapsulation of Essential Oil from Campomanesia adamantium Residue with Antioxidant Capacity Retention

The essential oil (EO) extracted from the peels and seeds of guavira (Campomanesia adamantium) was microencapsulated via complex coacervation between gelatin and gum arabic, followed by freeze-drying. This process aimed to reduce the volatility of the essential oil and protect bioactive compounds through the microcapsule wall. For process optimization, the influence of proportions of wall materials (gelatin: gum arabic ratios of 1:1, 1:2, 1:3, 2:1, and 3:1) and EO quantity (20% - 42.8%) on antioxidant capacity, morphology, and microencapsulation yield was measured using a central composite rotational design (CCRD). Additionally, the chemical composition and EO retention rate in the microcapsules were assessed. Gelatin: gum arabic ratio of 1:2 and EO quantity of 40.3% resulted in superior results, with the highest antioxidant capacity, a microencapsulation yield of 68%, and spherical morphology. Notably, the incorporation of a higher amount of EO led to an increase in the antioxidant capacity, with values reaching up to 99% equivalent to pure oil. All formulations maintained the same pure EO’s main constituents, including α-pinene, limonene, β-ocimene, and β-caryophyllene, indicated by gas chromatography coupled to mass spectrometry. Consequently, for the first time, EO microcapsules were successfully obtained from guavira residue, showing high microencapsulation yield and EO retention. This achievement adds sustainable value to residue normally discarded, which enables better use of residue generated by the food industry. Due to the preservation of its antioxidant capacity and enhanced retention of volatile compounds, these microcapsules promise applications in the food, pharmaceutical, and cosmetic industries, aligning with sustainability principles.

Development of an Air-assisted Dispersive Liquid-Liquid Microextraction Method as a Valuable Biomonitoring Tool for Exposure Assessment of Phthalates

In recent years, the number of epidemiological studies on phthalates that can inform and help update health risk assessments has grown rapidly. Developing reliable and rapid analytical methods for determining phthalate monoesters (m-PAEs) is an important biomonitoring tool for assessing exposure. In this study, a fast and sensitive method was developed to determine 15 m-PAEs in human urine samples as effective biomarkers for exposure assessment. Air-assisted dispersive liquid-liquid microextraction and liquid chromatography coupled to mass spectrometry were used. In order to determine the optimal conditions and model the variables influencing the extraction efficiency, a central composite rotatable design coupled with response surface methodology was used. Under the optimized conditions, the method achieved good linearities (R > 0.99), satisfactory intra- and inter-day accuracies (97–111%), and intra- and inter-day precision (RSD < 14%). The proposed procedure allowed the detection of the m-PAEs with limit of detection values between 0.02 and 0.10 ng mL-1, which makes the method sensitive and appropriate for assessing internal exposure to phthalates. The applicability of the proposed procedure was evaluated by screening fifty children’s urine from Brazil. High detection frequencies and urinary concentrations of several m-PAEs associated with using personal care products and diet were found.