Ethanol Concentration Research Articles

Postmortem/dynamic distribution of ethanol and its nonoxidative metabolites in poisoned rabbits.

Nonoxidative ethanol metabolites have been reported as ethanol biomarkers in clinical and forensic cases. However, their forensic toxicokinetics are still unclear. The study aimed to simultaneously research the postmortem distribution and dynamic distribution of ethanol and its nonoxidative metabolites in 62 poisoned rabbits. Firstly, 32 rabbits were randomly divided into three groups and sacrificed after three doses ethanol, and their organs were collected to study the postmortem distribution of ethanol and its nonoxidative metabolites. The results showed that the distribution trends of ethanol and its nonoxidative metabolites were basically same between different groups, and ethanol could be better detected by collecting body fluids, while the nonoxidative metabolites could be better detected by collecting the heart, liver, kidney and testis. Secondly, 30 rabbits after 1/2LD50 ethanol intragastric administration were sacrificed at 10 time points, and their organs were collected to study the dynamic distribution of ethanol and its nonoxidative metabolites. The results showed the concentrations of ethanol and its nonoxidative metabolites increased with time and then decreased. All analytes could be detected in all samples within 8h, with the exception of ethyl oleate, which kept high level in muscle and vitreous humor, and could be detected within 4h.

Sustainable use of agricultural residues to improve corn silage quality: Co-ensiling with oregano oil residues

The study aimed to evaluate the effect of oregano essential oil extraction residues (ORES) on the fermentation quality of corn silage. Non-fungal infected (NFI) and fungal infected (FI) corn were ensiled with 20% (wet weight) of ORES for 180 d. The inclusion of ORES delayed pH decline regardless of fungal infection. The inclusion of ORES did not adversely affect lactic acid (LA) production in NFI silages but retarded the initial LA fermentation of FI silages. Co-ensiling corn with ORES significantly decreased ethanol content. Co-ensiling FI corn with ORES significantly increased the fungal Chao1 and Shannon indices compared to FI-CON silages but did not affect the bacterial Chao1 and Shannon indices. The fungal infection aggravated the risk of Paenibacillus and Clostridium contamination, which was mitigated by co-ensiling with ORES. In conclusion, fungal infection suppressed ensiling fermentation, and heightened the risk of proliferation of undesirable bacteria, while ORES relieved these risks. Ensiling ORES with corn as forages is a potential and promising strategy for the efficient reusing of agro-industrial waste.

High-precision ethanol concentration microsensor with global spectra aided by the multi-layer perceptron

Whispering gallery mode (WGM) resonators can be used for precision measurement thanks to their high sensitivity, small size, and fast response time. Nevertheless, the design of such sensors is usually achieved by selecting a typical single-mode tracking method, which leads to low utilization of a great deal of information in the resonance spectrum and affects the precision. Here, we use the multi-layer perceptron (MLP) deep learning algorithm to train the global spectra and realize the high-precision measurement of ethanol concentration. Firstly, a large number of transmission spectra of different ethanol concentrations are collected and directly used as the original data sets. Secondly, the MLP algorithm is used for training and testing. Finally, the local feature dimension is extracted from the global features of the spectrum for prediction. The results show that the prediction accuracy of the global spectra sensing is 99.81%, which is 13.02% higher than that of extracting 10 local features. In addition, the prediction accuracy of the MLP is compared with four other commonly used machine learning (ML) algorithms, and the results show that the MLP algorithm has the highest prediction accuracy. Therefore, the high-precision ethanol concentration sensor proposed in this paper opens a new way for intelligent optical micro-resonator sensing.

CRYSTALLIZATION TEMPERATURE AND SOLVENT COMPOSITION EFFECT FOR ENHANCEMENT OF UNSATURATED FATTY ACIDS FROM PALM OIL USING UREA COMPLEXATION

Mono and Poly Unsaturated Fatty Acids (MUFAs/PUFAs) are vital nutritional sources for infants, adults, and the elderly. The content of monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) can be enhanced in vegetable oils or animal fats using a range of different techniques. The process of urea complexation is highly effective and efficient for concentrating monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) from vegetable oils. This study employed refined palm oil as the raw material that went through saponification and purification processes in order to generate fatty acids mixture. Subsequently, urea was introduced to create a complex chemical in the form of urea complexed fraction (UCF) and leaving the non-urea complexed fraction (NUCF). Gas chromatography was employed to analyze the fatty acid composition obtained from urea complexation. This study investigated the impact of different crystallization temperatures (-4°C, 8°C, 12°C, 22°C, and 30°C) and ethanol concentrations (ranging from 0% to 100%) on enhancing the unsaturated content and yield of fatty acids derived from palm oil. It also conducted predictive equations to determine the yield and fatty acids composition in the non-urea complexed fraction (NUCF) which are important for separation process design in chemical industries. The study revealed that increasing the crystallization temperature resulted in a larger yield in the liquid fraction (NUCF), but a lower concentration of monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs).

Physicochemical Properties and Biological Activities of Polysaccharides from Panax Notoginseng Separated by Fractional Precipitation.

The dried root of Panax notoginseng is a medicinal and food ingredient. P. notoginseng polysaccharides (PNPs) have physicochemical properties, which have not been fully elucidated. This study aimed to identify a method to separate the PNP fractions and investigate their activities. PNPs were prepared from roots by hot water extraction, deproteinization, and decolorization. PNP20, PNP40, and PNP60 fractions were isolated through stepwise ethanol precipitation at 20 %, 40 %, and 60 % concentrations, respectively. The three polysaccharide fractions were characterized using chromatography, spectroscopy, and thermogravimetric analysis, and their moisture retention, antioxidant, and tyrosinase-inhibition properties were evaluated. Monosaccharide composition analysis showed that the three PNPs contained mannose (Man), galacturonic acid (GalA), glucose (Glc), galactose (Gal), and arabinose (Ara) in different molar ratios. HPGPC analysis demonstrated that the polysaccharides precipitated with higher ethanol concentrations had lower molecular weights (Mw). Furthermore, all PNPs had distinct moisturizing and hygroscopic properties and antioxidant activities, with PNP60 showing better antioxidant properties and a competitive mixture of hygroscopic properties and tyrosinase inhibition. The chemical composition and structural characteristics of PNPs could affect their functional attributes. PNP60 has the potential to be a moisturizer and antioxidant and could be used in the development of cosmetic ingredients.

Clostridia as Promising Biofactory for Heterotrophic (Fructose) and Autotrophic (C1-Gas) Fermentation

This study compared the performance of Clostridium ljungdahlii and Clostridium aceticum in the fermentation of fructose and C1-gasses (CO, CO2, N2) to produce valuable products such as ethanol and acetic acid. In heterotrophic fermentation (fructose), C. ljungdahlii yielded high ethanol concentrations (350 mg/L) and acetic acid (500 mg/L), with optimal production at pH 8 on the first day of fermentation. Although autotrophic fermentation (C1-gasses) resulted in lower ethanol levels (200 mg/L), it remained a viable option. Conversely, C. aceticum predominantly produced acetic acid in both fermentation modes, with higher concentrations in the heterotrophic fermentation (1600 mg/L) than the autotrophic fermentation (380 mg/L). These findings demonstrate the versatility of both microorganisms for producing valuable metabolites. C. ljungdahlii shows promise for bioethanol production, while C. aceticum excels at generating acetic acid, a crucial component in bioplastics and various industrial processes.

Optimization of ultrasound-assisted anthocyanin extraction from agricultural waste purple corn silk for multifunctional hemp finishes

The utilization of agricultural wastes for textile dyeing has gained popularity due to their safe and environmentally friendly properties, as well as the resource sustainability. Natural dye extraction is usually achieved through solvent extraction, which is time-consuming, requires a lot of solvent, and degrades desired compounds at high temperatures. Thus, this study investigated ultrasound-assisted anthocyanin extraction from agricultural waste purple corn silk as natural functional colorants for hemp finishes, given the numerous health benefits associated with anthocyanin. In order to optimize the extraction processes and evaluate the synergistic impact of these conditions, response surface methodology was implemented. The optimum conditions were 1:15 material-liquid ratio, 47% ethanol concentration, 60°C, and 20 min, yielding 240.25 mg·L‒1 anthocyanin. The extracted anthocyanin was used for dyeing hemp fabrics and demonstrated satisfactory colorfastness, antibacterial action on both S.aureus and E.coli, with E.coli being more effective, and strong antioxidant (>80%). The dyed fabrics also exhibited their great UV shield (UPF value > 40+). Anthocyanin derived from purple corn silk could therefore be utilized as a natural functional color for medical and health products. Also, purple corn silk contains more anthocyanin than other natural sources, making it a promising natural anthocyanin resource in textile industry.

TRANSETHOSOMES FOR ENHANCED TRANSDERMAL DELIVERY OF METHOTREXATE AGAINST RHEUMATOID ARTHRITIS: FORMULATION, OPTIMISATION AND CHARACTERISATION

Objective: The study aimed to develop and optimise Methotrexate (MTX)-loaded Transethosomal Film-Forming Gel (TE FFG) for transdermal delivery to treat rheumatoid arthritis while alleviating the side associated with oral administration. Methods: The Transethosomes (TE) were prepared using the thin film hydration technique and incorporated into an FFG using chitosan. The Box-Behnken Design method was used to analyse the influence of independent variables such as the concentration of soya lecithin, surfactant, and ethanol on parameters including vesicle size, PDI (Polydispersity Index), zeta potential, and entrapment efficiency. The optimised transethosomal suspension was incorporated into the FFG using 3% chitosan and other excipients. In vitro drug release and ex vivo skin permeation of FFG were performed using Franz diffusion cells. Results: The vesicle size, PDI, zeta potential and entrapment efficiency of the optimised formulation of TE were 110.3 nm, 0.352,-14.4 mV and 49.36%, respectively. The Transmission Electron Microscopy (TEM) image showed that the vesicles were uniform and spherical. The in vitro drug release study was higher for Conventional (CL) FFG) than TE FFG and the drug release mechanism was fitted into the Higuchi model. The permeation was higher for TE FFG, with the steady-state flux being 1.55 times greater than the CL FFG. The skin irritation test on Wistar rats revealed no indication of irritation on the skin. The histopathology examination showed a significant reduction in the inflammatory cells in the treated group. Conclusion: Therefore, the results concluded that the formulated MTX-loaded TE FFG could be a potentially promising substitute for the oral delivery of methotrexate

Assessing Process Conditions on Xylose Fermentation in Spathaspora passalidarum: Effects of pH, Substrate-to-Inoculum Ratio, Temperature, and Initial Ethanol Concentration.

Bioethanol represents a clean and renewable alternative to fossil fuels, offering a significant reduction in environmental impact. Second-generation ethanol (2G) is produced using lignocellulosic biomass, which presents additional challenges due to the presence of hemicellulose. The pentose sugars within hemicellulose cannot be efficiently metabolized by conventional yeast strains like Saccharomyces cerevisiae. Consequently, the yeast Spathaspora passalidarum has emerged as a promising candidate for mixed fermentation processes, given its ability to utilize xylose. This study presents an in-depth metabolic, stoichiometric, and kinetic analysis of the fermentation performance of Sp. passalidarum NRRL Y-27907 in mixed glucose and xylose cultures. Emphasis was placed on examining variables from a novel perspective compared to existing literature. Specifically, the impacts of initial inoculum-substrate ratios, substrate composition, pH, temperature, and ethanol sensitivity were analyzed using a mathematical bioprocess approach. Sp. passalidarum NRRL Y-27907 exhibited sequential sugar consumption, with xylose being utilized only after glucose was exhausted. Ethanol yields in mixed cultures were comparable to those in individual-sugar cultures. The best fermentative performance was observed at 30°C, with 25g/L of xylose and an inoculum of 0.50g/L. The strain exhibited significant robustness at pH 4.0 and was notably affected by initial ethanol concentrations up to 20g/L. These findings provide crucial insights into the metabolic and fermentative behavior of Sp. passalidarum NRRL Y-27907, offering valuable information for the design of consolidated bioprocesses from lignocellulosic materials.

Antibacterial Activity of Ethanol Extract Red (Jatropha gossypifolia) Leaves Against Bacterial Skin Infections by Agar Diffusion

Red Jatropha gossypifolia plant is a type of Jatropha with purplish red leaves which the chemical compounds are found are calcium oxalate, jatroidene, interquinones, flavonoids, flobatin and phenolics, and these compounds can be used as an anticoagulant, anti-inflammatory, analgesic and antibacterial. The aim of this research is to determine the antibacterial activity of red Jatropha leaves ethanol extract against bacteria causes skin infections by Agar Diffusion. The result of screening antibacterial test of red Jatropha leaves ethanol extract with a concentration of 0,1% active against bacteria Staphylococcus aureus, Staphylococcus epidermidis, Propionibacterium acne and Pseudomonas aeruginosa. The result of analysis Minimum Inhibitor Concentration (MIC) and Minimum Bactericidal Concentration (MBC) ethanol extract obtained MIC value = 0.1% to bacteria acid, MBC value = 0.05% to bacteria acid, and the result of antibacterial activity of ethanol extract obtained the largest inhibitory zone diameter at a concentration of 12.8% was 13.577 mm against Staphylococcus aureus.

Optimization of Microwave-Assisted Polyphenol Extraction and Antioxidant Activity from Papaya Peel Using Response Surface Methodology and Artificial Neural Network

The objective of the present study is to determine the optimal conditions of microwave-assisted extraction (MAE) such as microwave power (MWP), irradiation time (I-time), ethanol concentration (EtOH%), and solvent-to-solid ratio (S/S) for maximizing total polyphenol content (TPC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity from papaya peel. Box-Behnken design (BBD) was used considering MWP 300–600 W, I-time 60-120 s, EtOH% 30-70%, and S/S 30-70 mL/g. Additionally, response surface methodology (RSM) and artificial neural networks (ANN) were employed for modelling, with cross-validation to enhance reliability. These models were combined with the desirability function (DF) and/or genetic algorithm (GA) optimization approaches. Maximizing TPC and DPPH activity while maintaining MWP, I-time, EtOH%, and S/S within their respective ranges using hybrid optimization approaches (RSM-DF: TPC = 1058 mgGAE/100g, and DPPH = 83%, RSM-GA: TPC = 1064 mgGAE/100g and DPPH = 79%, and ANN-GA: TPC = 1086 mgGAE/100g, and DPPH = 83%,) yielded consistent optimal results. An additional optimization approach (RSM-DF: TPC = 955 mgGAE/100g, and DPPH = 90%), aimed at minimizing MWP, I-time, EtOH%, and S/S while maximizing TPC and DPPH activity, showed a significant reduction of approximately 3 L in ethanol consumption for each 100 g of dry samples. The maximized TPC and DPPH activity in all four approaches showed a significant (p < 0.05) alignment with their corresponding validation tests, demonstrating the better performance of these modelling and optimization processes. In terms of assessing the effectiveness of microwave assistance, conventional solvent extraction was also performed, maintaining a 70 mL/g S/S ratio of 55% ethanol at 60°C for 2 h. This method resulted in lower values of TPC (857 ± 23 g GAE/100g) yield and DPPH activity (72 ± 5%) compared to the optimized condition of MAE.

Optimization of ultrasound-assisted extraction of astaxanthin from black tiger shrimp (Penaeus monodon) shells using deep eutectic solvent and ethanol as a co-solvent

The study aimed to enhance the extraction of astaxanthin (ASX) from black tiger shrimp shells by combining Deep eutectic solvent (DES) and ultrasound-assisted extraction (UADE). The DES used in the research consisted of choline chloride (Ch) and citric acid (CA) in a 1:2 molar ratio with 20% water. Response surface methodology (RSM) utilizing a Box-Behnken design (BBD) was employed to optimize the UADE conditions, considering ultrasound power (200 – 400 W), ethanol concentration in the DES (5 – 65 %), and extraction time (5 – 45 min). The optimal UADE parameters identified by BBD were 330 W ultrasound power, 35% ethanol content, and 33 min of extraction, resulting in the highest ASX content of 47.42 μg/g, closely matching the predicted value of 48.65 μg/g. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analysis revealed structural alterations in samples treated with DES-based UAE, setting it apart from soxhlet extraction, maceration, and ethanol-based DES extraction. The outcomes indicated that UADE outperformed traditional extraction methods like soxhlet extraction, maceration, and ultrasound-assisted ethanol extraction (UAET) regarding ASX yield and antioxidant activity, while also needing shorter extraction durations. These results underscore UADE as a productive and eco-friendly approach for extracting ASX from shrimp shells.

Insights into pharmaceutical co-crystallization using coherent Raman microscopy

Formulating active pharmaceutical ingredients (APIs) as co-crystals requires a thorough understanding of co-crystallization behavior under different process conditions. This study employs two forms of coherent Raman microscopy, narrowband coherent anti-Stokes Raman scattering (CARS) and stimulated Raman scattering (SRS) with spectral focusing, to study co-crystallization via liquid-assisted ball milling. Indomethacin and nicotinamide served as the model API and co-former, and the results were compared with established analytical methods. Narrowband CARS, with univariate peak position analysis, was useful to visualize co-crystal formation, but suffered some degree of signal mixing that affected component identification. Hyperspectral SRS imaging, combined with classical least squares multivariate analysis, separated the different components with high confidence and proved to be a robust and rapid tool to qualitatively and quantitatively image co-crystallization. The coherent Raman imaging results explained divergent co-crystallization endpoints obtained with the conventional solid-state analysis methods. CARS and SRS microscopies also revealed the presence of otherwise undetected trace forms. Finally, we also demonstrated the dramatic reversal of partial co-crystal formation during milling, depending on ethanol content. Overall, the study demonstrates the added value coherent Raman microscopy can provide for analysis of co-crystallization processes.

Impact of yeast selection on composition of vinegar fermented from pomace of a Finnish apple cultivar

Alcoholic beverages and vinegar products were produced using the pomace of a Finnish apple cultivar, and the influence of yeast strains on the non-volatile and volatile compound contents were studied. Apple pomace mashes were fermented with Saccharomyces cerevisiae, Torulaspora delbrueckii, and sequential inoculation with Lachancea thermotolerans and S. cerevisiae to produce alcoholic beverages. Commercial non-pasteurized vinegar was used as a starter to ferment alcoholic beverages into vinegars. Ethanol, acetic acid, sugars and organic acids were determined using GC-FID. A total of 63 volatile compounds were detected in the samples using HS-SPME-GC-MS. Alcoholic beverages fermented with the sequential inoculation had the highest total content of organic acids, and pure inoculation with T. delbrueckii resulted in the highest total content of sugars. Selection of different yeast strains did not alter the content of ethanol or acetic acid, but it significantly influenced the composition of volatile compounds in alcoholic beverages and vinegars. Compared to initial apple pomace mash, significant increases in the contents of ethyl esters (up to 4810-folds), higher alcohols (up to 24-folds) and volatile acids (up to 1853-folds) were observed in fermented products depending on the yeasts used. The main volatile compounds in vinegars prepared from S. cerevisiae fermented beverage were 2-phenylethanol, octanoic acid, and decanoic acid, from T. delbrueckii beverage 2-methylpropanoic acid and 3-methylbutanoic acid, and from sequential fermentation ethyl acetate, and ethyl 2-hydroxypropanoate. In conclusion, non-Saccharomyces yeasts have potential to produce more complex aromatic profile to fermented products derived from by-products of apple juice processing.

Ethanol stability from nine years of a blind quality control program in blood alcohol analysis.

A blind quality control (BQC) program in blood alcohol analysis was implemented at the Houston Forensic Science Center (HFSC) in September 2015. By mimicking authentic toxicology blood evidence, the laboratory can perform a concurrent evaluation of their technical and administrative casework procedures and test the accuracy and reliability of their volatile analysis method in a format that is blinded to the analyst. From September 2015 to November 2023, HFSC's Quality Division submitted 1228 antemortem whole blood samples: 292 ethanol-negative samples and 936 ethanol-positive samples at sixteen target concentrations (0.051, 0.080, 0.100, 0.110, 0.120, 0.130, 0.150, 0.160, 0.170, 0.180, 0.190, 0.200, 0.230, 0.240, 0.250, and 0.260 g/dL). A second, unopened blood tube in 168 of the 1228 BQCs was also analyzed after 721-1140 days: 24 ethanol-negative samples and 144 ethanol-positive samples at five target concentrations (0.080, 0.100, 0.130, 0.180, and 0.240 g/dL). All 316 ethanol-negative samples remained negative. After 42-758 days, the average (median, range) change in ethanol concentration of the 936 positive samples was -1.4% (-1.3%, -12.0% to +8.4%) with a statistically significant difference (P < 0.001) observed for the gradual decline in blood alcohol concentration (BAC) over time. The average BAC percentage differences per target concentration, ranged from -6.4% (-0.008 g/dL) to +5.7% (+0.011 g/dL), were within HFSC's current measurement uncertainty (9.4% at k=3), showing no apparent correlation between the change in ethanol and the theoretical target concentration. As the analysis time between the two blood specimens from the same evidence kit extended, the loss in ethanol significantly increased (P < 0.001).

Effect of H2O2/ascorbic acid degradation and gradient ethanol precipitation on the physicochemical properties and biological activities of pectin polysaccharides from Satsuma Mandarin

In this work, three degraded polysaccharides (DMPP-40, DMPP-60, DMPP-80) were successfully obtained by H2O2/ascorbic acid degradation and gradient ethanol precipitation from Satsuma mandarin peel pectin (MPP), and their physicochemical properties, antioxidant and prebiotic activities were investigated. The molecular weight of MPP, DMPP-40, DMPP-60, DMPP-80 were determined to be 336.83 ± 10.57, 18.93 ± 0.54, 26.07 ± 0.83 and 8.71 ± 0.27 kDa, respectively. The ethanol concentration significantly affected the physicochemical properties of DMPPs. DMPP-60 showed the highest yield (69.07 %) and uronic acid content (64.85 %), DMPP-80 showed the lowest molecular weight (8.71 kDa), and the composition and proportion of monosaccharides of DMPPs were significantly different. Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (1H NMR) confirmed that DMPPs exhibited similar functional groups, while X-ray diffraction (XRD) indicated that DMPP-40 possessed some crystallographic sequences. Scanning electron microscopy (SEM) images directly verified the fragmented structure and reduced surface area of DMPPs. Besides, the H2O2/ascorbic acid treatment could obviously reduce the apparent viscosity and thermal stability of MPP. Meanwhile, the results of bioactivity assay showed that DMPPs possessed better antioxidant activity and probiotics pro-proliferative effects compared with MPP. DMPP-80 could significantly inhibit lipopolysaccharides (LPS)-stimulated production of inflammatory factors (including nitric oxide (NO), interleukin (IL)-6, tumor necrosis factor (TNF)-α and interleukin (IL)-1β) in RAW264.7 cells. Results suggest that the H2O2/ascorbic acid combined with gradient ethanol precipitation has potential applications in degradation and separation of MPP to improve its biological activities.

Molybdenum-doping to enhance the deprotonation ability of nickel-based hydroxide electrocatalysts for ethanol oxidation

With technological advancements, the practical application of ethanol oxidation reaction (EOR) is becoming increasingly promising, yet the need for higher ethanol concentrations highlights the growing importance of the deprotonation ability (Ni2+ to Ni3+) of the catalyst. The deprotonation ability is the key step for nickel-based catalysts in EOR, as it is essential for Ni2+ to continuously undergo deprotonation to transform into Ni3+ in order to maintain the continuous EOR. Herein, we developed Mo-doped Ni(OH)2 nanosheets by a hydrothermal method. The Mo-doped Ni(OH)2 nanosheets show excellent EOR performance due to the high valence doping of Mo, the onset potential of the oxidation peak (Ni2+ to Ni3+) appears at a position with a small overpotential,. The in-situ Raman spectroscopy technique further characterized the increase in NiOOH in the process of EOR. The Mo-doped Ni(OH)2 nanocomposite catalyst facilitates the oxidation of Ni2+ into Ni3+. Based on the above theoretical guidance, Mo-doped Fe/Ni(OH)2 nanosheets was designed and synthesized. The outstanding EOR performance of the Mo-Fe/Ni(OH)2-3 showed a potential of 1.352 V at 10 mA cm−2. The catalyst was used to design three-electrode reversible zinc-ethanol-air battery (T-RZEAB), which effectively overcomes the opposing kinetic and thermodynamic requirements for EOR and oxygen reduction reaction (ORR) catalysts in the oxygen electrode. The charging voltage of T-RZEAB with Mo-Fe/Ni(OH)2-3 is 240 mV lower than that of a traditional zinc-air battery at 25 mA cm−2.

A combined mechanistic and empirical models for tailored microwave-assisted extraction of rice bran phenolic

ABSTRACT Rice bran is a promising source of functional food due to its high phenolic content. Microwave-assisted extraction (MAE) has become a widely used method for optimizing phenolic extraction from rice bran. However, understanding the phenolic extraction process using the MAE method is challenging due to the system’s complexity. Modeling and simulation are powerful tools to provide a better understanding of how the system behaves and can be optimized. This study proposes a novel approach that combines mechanistic and empirical models (gray box) to predict the phenolic content in rice bran extraction using MAE. It involved phenolic extraction using different ethanol concentrations (40%, 60%, 80%), microwave application time (1 min, 2 min, 3 min), and microwave power (90 W, 180 W, 270 W). The results showed a good agreement between experimental and computed extraction yields, as indicated by the reported statistical parameters and gray box model. The optimum conditions were reached at 60% ethanol concentration, 2-min microwave application time, and 180 W microwave power with the phenolic content at 0.534 mg/mL (model) and 0.561 mg/mL or 25.06 mg/g (experiment). Following the study, this combined approach can potentially reduce the time and cost required for optimization studies of phenolic extraction.

Optimization of microwave assisted extraction of bioactive compounds in oregano and lovage ethanolic extracts

Oregano and lovage contain a wide variety of bioactive compounds, but conventional extraction techniques usually generate small amounts of secondary metabolites. Thus, the extraction method and the recovery of these compounds represent a current challenge. The aim of this study was to optimize 3 microwave-assisted extraction (MAE) parameters, by response surface methodology (RSM), to obtain ethanolic bioactive extracts from oregano and lovage. The obtained extracts were assessed for their total phenolic content (TPC), antioxidant activity (AA), radical scavenging activity (I%), and antibacterial activity, by determining the minimal inhibitory concentration (MIC) against Escherichia coli and Staphylococcus aureus. The ethanol concentration (X1: 40, 60 and 80%), microwave power (X2: 160; 480 and 800 W), and repetitions (X3: 1 to 10 times) were set as independent variables. The obtained models were validated with new experimental results, and confirmed for the 3 response parameters: TPC, AA, and I%. High-performance liquid chromatography (HPLC) was used to identify and quantify the main phenolic compounds in both optimum oregano and lovage extracts. The optimal extraction parameters were obtained with 49% ethanol, 160 W and 10 repetitions for oregano, whereas for lovage, 53% ethanol, 800 W power, and 10 extraction repetitions were optimal.

Multianalyte Detection with Metasurface-Based Midinfrared Microspectrometer.

Midinfrared (2.5-25 μm) spectroscopy is an ideal tool for identifying chemicals in a nondestructive manner. The traditional platform is a Fourier transform infrared (FTIR) spectrometer, but this is too bulky, expensive, and power-hungry for many applications. There is therefore a growing demand for small, lightweight, and cost-effective microspectrometers for use in the field. One emerging platform is the filter-array detector-array microspectrometer. It pairs a broadband detector array with a thin and rigid array of spectral filters to offer a robust, compact platform for real-time in situ sensing. However, most demonstrations have only focused on identifying a single chemical against a null sample, even though many applications would involve multianalyte detection. In this work, we show a rare attempt at simultaneously tracking multiple analytes with a metasurface filter-array microspectrometer. The metasurface consists of periodic lattices of subwavelength circular apertures in an aluminum layer to create an array of bandpass filters. The filter array is imaged with an off-the-shelf microbolometer via a reverse-lens imaging setup to simultaneously monitor the concentration of ethanol and methanol in gasoline. This represents an important application of fuel quality monitoring. Chemometric models (PLS and SVR) are trained and tested on gasoline blends with ethanol and methanol contents, both ranging from 0% to 20% v/v. A support vector machine regression (SVR) model with a cubic kernel was found to have the lowest combined prediction errors. The root-mean-square-error of prediction (RMSEP) for ethanol and methanol are 1.23% and 1.84% v/v; the corresponding pseudounivariate limit of detection is found to be 4.22% and 6.86% v/v, respectively. This work takes the emerging field of metasurface-based mid-infrared spectrometers from single- to multianalyte detection, thereby considerably expanding their range of potential applications.