One Variable At A Time Research Articles

Rapid identification of fragrant rice using starch flavor compound via NIR spectroscopy coupled with GC–MS and Badh2 genotyping

The identification of fragrant rice varieties using near-infrared reflectance spectroscopy (NIRS) models has attracted extensive attention from regulatory authorities worldwide. In this study, 138 fragrant and 54 nonfragrant rice varieties were planted in the same region and distinguished using sensory evaluation, gas chromatography–mass spectrometry analysis, and betaine aldehyde dehydrogenase 2 (Badh2) genotyping. Then, the 2-acetyl−1-pyrroline (2-AP) content was assessed based on partial least-squares discriminant (PLS-DA) models generated after 2nd individually or combined with SNV/MSC/smoothing preprocessing successfully classified fragrant rice both in the calibration and predictive sets. Moreover, design of experiments (DoE)-based preprocessing selection was employed as an effective strategy to optimize the calibration models compared with the one variable at a time (OVAT) method. Further, Badh2 genotype sample screening assisted with identifying authentic fragrant rice and guaranteed the NIRS model's prediction accuracy in identifying fragrant rice. In conclusion, the high throughput PLS-DA multivariate method coupled with NIRS data was applied to identify fragrant rice varieties in routine monitoring and was effective, accurate, and rapid.

Production of Amylase by Solid State Fermentation Using Agricultural Waste

This study presents a comprehensive investigation into the production of amylase, a crucial enzyme with wide-ranging industrial applications, using locally sourced substrates from Kachchh, Gujarat. The research employed the Bacillus licheniformis strain and substrates such as coconut, rice husk, wheat bran, paddy straw, and maize straw. The study found paddy straw to be the most promising substrate for amylase production. The research also systematically optimized various process parameters for amylase production in Solid-State Fermentation (SSF) using the One Variable at a Time (OVAT) method. These parameters included incubation period, temperature, inoculum level, additional carbon sources, starch concentrations, additional nitrogen sources, initial pH, different mineral salt ions, initial moisture level, and surfactants. The results showed that the optimal conditions for maximum amylase yield were an incubation period of 48 hours, an incubation temperature of 35°C, an inoculum level of 10%, starch as the additional carbon source, a starch concentration of 2.5%, yeast extract as the additional nitrogen source, an initial pH of 7, NaCl as the mineral salt, an initial moisture level of 75%, and Tween 80 as the surfactant. This research provides a reliable and sustainable approach to enzyme production, offering valuable insights for the optimization of the solid-state fermentation process for maximum amylase production.

Biopolyol synthesis via ring-opening of epoxidized soybean oil with glycerol utilizing a novel sulfonic-functionalized ionic liquid as the catalyst at low temperature

Herein, a novel synthetic strategy for the preparation of soybean oil-based biopolyol has been established using ionic liquids (ILs) as the green and efficient catalysts via the ring-opening reaction of epoxidized soybean oil (ESO) with glycerol as the nucleophile. Among them, the sulfonic-functionalized IL 1-butylsulfonic-3-methylimidazolium trifluoromethanesulfonate ([BSO3HMIM]OTF) exhibited superior catalytic performance in the ring-opening reaction under mild reaction conditions, demonstrating excellent catalytic efficiency and a high hydroxyl number of the synthesized biopolyol products. The impacts of various reaction variables on the ring-opening reaction were systematically investigated employing one variable at a time (OVAT) and response surface methodology (RSM). Under the optimized reaction parameters, including a catalyst loading of 1.2 wt%, a reaction duration of 4 h, a molar ratio of glycerol to epoxy groups of 3:1, and a tert-butanol to substrate of 1:1 (w/w) at 45 °C, the highest epoxy group conversion rate and the hydroxyl number were found to be 98.0 ± 0.6 % and 285.0 ± 1.4 mg KOH/g, respectively. Characterization by NMR and FT-IR confirmed the successful synthesis of biopolyols, while thermal stability and rheological studies further highlighted their suitability for diverse industrial applications as valuable chemical intermediates. These findings underscore the potential of sulfonic-functionalized [BSO3HMIM]OTF IL as efficient and eco-friendly catalyst in sustainable biopolyol production.

Amino-functionalization of PVA/TiO2-CeO2 nanohybrid adsorbent for the removal of selenium ions from aqueous solutions: Equilibrium and kinetics studies

ABSTRACT In this study, a hybrid nanoadsorbent (HnA), (PVA/TiO2-CeO2), was synthesized and amino-functionalized by 3-aminopropyltriethoxysilane (APTES) to produce AHnA, for use in an advanced selenium adsorption study focusing on nonlinear equilibrium and kinetics models. AHnA was characterized using XRD, FTIR spectroscopy, SEM, and EDX elemental analyses, as well as BET-BJH techniques. According to the FTIR results, APTES has successfully cross-linked the PVA chain and introduced amine groups on the surface. Moreover, the modification resulted in an increase in the total pore volume from 0.0061 cm3/g in HnA to 0.021 cm3/g in AHnA. Several adsorption experiments were conducted to determine the impact of varying contact times within a pH range of 1 to 8 and concentrations ranging from 5 to 200 mg/L, using a One-Variable-At-a-Time (OVAT) procedure. Accordingly, a dosage of 2 g/L of modified nanocomposite exhibits optimal performance for removing selenium from a 20 mg/L solution at an acidic pH of 3 during 300 minutes of contact with selenium ions, while conforming to a pseudo-second-order kinetic model. The assessment of various nonlinear isotherm models for analyzing equilibrium data revealed that the experimental data of selenium adsorption conformed to a generalized isotherm, showing a maximum monolayer adsorption capacity of 17.643 mg/g.

Research on disturbance influence of goaf residual deformation on simply supported beam bridge

In order to analyze the stability of the bridge above the goaf, the disturbance influence of goaf residual deformation on the bridge is studied. Firstly, an equivalent numerical simulation method of goaf residual deformation evolution process is studied by quantitative analysis the sensitivity of residual subsidence to the rock parameters using the OAT (one-variable-at-a-time). Then, the collaborative deformation of ground, pile, and bridge floor is studied under the condition of a simply-supported beam bridge above the goaf center. Finally, the mechanism of collaborative deformation of ground, pile, and bridge floor is revealed. The results show that the goaf residual deformation process can be obtained by weakening the elastic modulus of fractured rock in the caving zone. At the final residual deformation stage, the subsidence ratio of ground to pile is about 10, and the subsidence ratio of pile to bridge floor is about 2, while the ground horizontal movement ratio of ground to pile is about 7, and the bridge floor horizontal movement can be ignored. The bridge floor is always in the positive curvature influence zone, and the pile has an inhibitory effect on the curvature deformation of the bridge floor. The compression deformation occurs between the piles locations, while the tensile deformation occurs at the pile location. The evolution of negative frictional resistance derived from goaf residual deformation is the main reason for the change in the collaborative deformation law among the ground, pile and bridge floor. This research can provide scientific support and theoretical basis for the design, construction, and protection of the bridge above the goaf center, and can also provide reference for the stability evaluation of bridge above goaf under other conditions.

Optimization, gene cloning, expression, and molecular docking insights for enhanced cellulase enzyme production by Bacillus amyloliquefaciens strain elh1

BackgroundIn this study, we isolated a cellulase-producing bacterium, Bacillus amyloliquefaciens strain elh, from rice peel. We employed two optimization methods to enhance the yield of cellulase. Firstly, we utilized a one-variable-at-a-time (OVAT) approach to evaluate the impact of individual physical and chemical parameters. Subsequently, we employed response surface methodology (RSM) to investigate the interactions among these factors. We heterologously expressed the cellulase encoding gene using a cloning vectorin E. coli DH5α. Moreover, we conducted in silico molecular docking analysis to analyze the interaction between cellulase and carboxymethyl cellulose as a substrate.ResultsThe bacterial isolate eh1 exhibited an initial cellulase activity of 0.141 ± 0.077 U/ml when cultured in a specific medium, namely Basic Liquid Media (BLM), with rice peel as a substrate. This strain was identified as Bacillus amyloliquefaciens strain elh1 through 16S rRNA sequencing, assigned the accession number OR920278 in GenBank. The optimal incubation time was found to be 72 h of fermentation. Urea was identified as the most suitable nitrogen source, and dextrose as the optimal sugar, resulting in a production increase to 5.04 ± 0.120 U/ml. The peak activity of cellulase reached 14.04 ± 0.42 U/ml utilizing statistical optimization using Response Surface Methodology (RSM). This process comprised an initial screening utilizing the Plackett–Burman design and further refinement employing the BOX -Behnken Design. The gene responsible for cellulase production, egl, was effectively cloned and expressed in E. coli DH5α. The transformed cells exhibited a cellulase activity of 22.3 ± 0.24 U/ml. The egl gene sequence was deposited in GenBank with the accession number PP194445. In silico molecular docking revealed that the two hydroxyl groups of carboxymethyl cellulose bind to the residues of Glu169 inside the binding pocket of the CMCase. This interaction forms two hydrogen bonds, with an affinity score of −5.71.ConclusionsOptimization of cultural conditions significantly enhances the yield of cellulase enzyme when compared to unoptimized culturing conditions. Additionally, heterologous expression of egl gene showed that the recombinant form of the cellulase is active and that a valid expression system can contribute to a better yield of the enzyme.

Removal of N-Nitrosodiphenylamine from contaminated water: A novel modeling framework using metaheuristic-based ensemble models

Investigating the complex interactions among physicochemical variables that influence the adsorptive removal of pollutants is a challenge for conventional one-variable-at-a-time (OVAT) batch methods. The adoption of machine learning-based chemometric prediction models is expected to be more accurate than the conventional method. This study proposed a novel modeling framework for predicting and optimizing the adsorptive removal of N-Nitrosodiphenylamine (NDPhA). Initially, models were trained by using OVAT data, with their hyperparameters subsequently fine-tuned through Bayesian optimization. In the second phase, the particle swarm optimization (PSO) technique was adopted to identify optimal parameters, specifically time, concentration, temperature, pH, and dose, to ensure the highest removal. The adopted analytical method enhances both prediction accuracy and removal efficiency. Utilizing OVAT data for NDPhA removal, the XGBoost regressor significantly outperformed other models. With a correlation coefficient of 0.9667 in the testing dataset, the XGBoost model exhibited its accuracy, emphasized by its low mean squared errors of 28.45 and mean absolute errors of 0.0982. Feature importance analysis consistently identified time and concentration as the most critical factors across all models.

Efficient production of biodiesel from palm fatty acid distillate using a novel hydrochar-based solid acid catalyst derived from palm leaf waste

To combat fuel shortages, pollution, and the exhaustion of natural oil resources, an environmentally friendly alternative to fossil fuels, such as biodiesel, is essential for meeting global transportation demands. A novel heterogeneous acid catalyst for production of biodiesel from low-cost, high free fatty acid feedstocks was synthesized in this study by activating and impregnating hydrochar from palm leaf (PL) waste with H3PO4 and H2SO4. Subsequently, the sulfonated catalyst was utilized for the esterification of palm fatty acid distillate (PFAD). FT-IR, XRD, FESEM, EDX, BET, TGA, and surface acidity methods were employed to characterize the acid catalyst. Using the one-variable-at-a-time (OVAT) technique, the optimized reaction conditions for esterification of PFAD using the hydrochar-based catalyst were 4 wt% catalyst loading, 353.15 K reaction temperature, 4 h reaction time, and 18:1 methanol: PFAD molar ratio. At these conditions, a maximum biodiesel yield of 93.56% was achieved. The catalyst exhibited excellent reusability and stability throughout five reaction cycles, maintaining biodiesel yields above 80% after each cycle. Analysis of the fuel properties revealed that the biodiesel derived from PFAD met the physiochemical criteria outlined in ASTM D6751, the American biodiesel standard. The kinetic study revealed that the esterification reaction followed pseudo-first-order kinetics with an activation energy (Ea) of 23.70 kJ/mol. Furthermore, the thermodynamic enthalpy (∆H*) and Gibbs' free energy (∆G*) of esterification were 20.9 and 33.41 kJ/mol, respectively, indicating that the reaction was an endothermic and non-spontaneous process.

The usability of green deep eutectic solvents in hollow fiber Liquid-Phase microextraction for the simultaneous extraction of analytes of different Natures: A comprehensive study

In the current study, a wide range of deep eutectic solvents (DESs) with different properties (hydrophilic, hydrophobic, ionic, and nonionic) were prepared in the initial phase. Subsequently, an assessment was conducted to evaluate some characteristics of the produced DESs, including their stability at room temperature and their capacity to extract three distinct types of analytes (anionic, cationic, and non-ionic) simultaneously through hollow fiber-liquid phase microextraction (HF-LPME) technique. To carry out the extraction procedure, the prepared DESs were inserted into the pores (as supported liquid membrane (SLM)) and lumen of hollow fiber membrane (HF) to apply two-phase and three-phase HF-LPME techniques. After a thorough evaluation, the three-phase HF-LPME technique (HF(3)-LPME) was chosen by using a mixture of menthol/TBAB-based hydrophobic DES (DES-35) as SLM and the mixture of malic acid/citric acid/water-based hydrophilic DES (DES-2) as an extraction solvent in the lumen of HF. All factors affecting the extraction recovery (including pH, extraction time, extraction temperature, stirring speed, and salt effect) were optimized utilizing the one-variable-at-a-time (OVAT) methodology. After applying the extraction procedure, all extracted samples were analyzed using the UV–Vis spectrometer and results were recorded at different wavelengths including 655 nm for Methylene blue, 550 nm for Amaranth, and 375 nm for Quercetin. The calibration graphs showed linearity in the range of 20.0–1500 µg/L, with a limit of detection of 6.2–15.1 µg/L and correlation coefficients higher than 0.9913 for the studied analytes. Moreover, the intra-day RSD, inter-day RSD, preconcentration factor (PF), enrichment factors (EF), and extraction recoveries (ER%) were obtained in the range of 3.1–4.8, 3.8–6.7, 125, 102.9–111.4, and 82.3–89.1 %, respectively. The use of the selected DES in the HF-LPME methodology resulted in an ecologically friendly strategy, as evidenced by the use of green metrics from the SPMS tool. The proposed strategy is also considered environmentally friendly due to its use of minimal solvents, waste reduction, and low energy consumption. The proposed technique effectively and simultaneously extractedmethylene blue, amaranth, and quercetin analytes in different real samples.

Surface roughness prediction of AISI D2 tool steel during powder mixed EDM using supervised machine learning

Surface integrity is one of the key elements used to judge the quality of machined surfaces, and surface roughness is one such quality parameter that determines the pass level of the machined product. In the present study, AISI D2 steel was machined with electric discharge at different process parameters using Jatropha and EDM oil. Titanium dioxide (TiO2) nanopowder was added to the dielectric to improve surface integrity. Experiments were performed using the one variable at a time (OVAT) approach for EDM oil and Jatropha oil as dielectric media. From the experimental results, it was observed that response trends of surface roughness (SR) using Jatropha oil are similar to those of commercially available EDM oil, which proves that Jatropha oil is a technically and operationally feasible dielectric and can be efficiently replaced as dielectric fluid in the EDM process. The lowest value of S.R. (i.e., 4.5 microns) for EDM and Jatropha oil was achieved at current = 9 A, Ton = 30 μs, Toff = 12 μs, and Gap voltage = 50 V. As the values of current and pulse on time increase, the S.R. also increases. Current and pulse-on-time were the most significant parameters affecting S.R. Machine learning methods like linear regression, decision trees, and random forests were used to predict the surface roughness. Random forest modeling is highly accurate, with an R2 value of 0.89 and an MSE of 1.36% among all methods. Random forest models have better predictive capabilities and may be one of the best options for modeling complex EDM processes.

Deep eutectic solvent-based shaking-assisted extraction for determination of bioactive compounds from Norway spruce roots.

Polyphenolic compounds play an essential role in plant growth, reproduction, and defense mechanisms against pathogens and environmental stresses. Extracting these compounds is the initial step in assessing phytochemical changes, where the choice of extraction method significantly influences the extracted analytes. However, due to environmental factors, analyzing numerous samples is necessary for statistically significant results, often leading to the use of harmful organic solvents for extraction. Therefore, in this study, a novel DES-based shaking-assisted extraction procedure for the separation of polyphenolic compounds from plant samples followed by LC-ESI-QTOF-MS analysis was developed. The DES was prepared from choline chloride (ChCl) as the hydrogen bond acceptor (HBA) and fructose (Fru) as the hydrogen bond donor (HBD) at various molar ratios with the addition of 30% water to reduce viscosity. Several experimental variables affecting extraction efficiency were studied and optimized using one-variable-at-a-time (OVAT) and confirmed by response surface design (RS). Nearly the same experimental conditions were obtained using both optimization methods and were set as follows: 30mg of sample, 300mg of ChCl:Fru 1:2 DES containing 30%w/w of water, 500rpm shaking speed, 30min extraction time, 10°C extraction temperature. The results were compared with those obtained using conventional solvents, such as ethanol, methanol and water, whereby the DES-based shaking-assisted extraction method showed a higher efficiency than the classical procedures. The greenness of the developed method was compared with the greenness of existing procedures for the extraction of polyphenolic substances from solid plant samples using the complementary green analytical procedure index (ComplexGAPI) approach, while the results for the developed method were better or comparable to the existing ones. In addition, the practicability of the developed procedure was evaluated by application of the blue applicability grade index (BAGI) metric. The developed procedure was applied to the determination of spruce root samples with satisfactory results and has the potential for use in the analysis of similar plant samples.

Poly-(ionic liquid) coated with magnetic nanoparticles for micro solid phase extraction of polycyclic aromatic hydrocarbons in food samples

Poly(methyl methacrylate-vinyl imidazole bromide) (poly-MMA-IL)-grafted magnetic nanoparticles were successfully developed and applied in the micro-magnetic solid phase extraction (μ-MSPE) for 16 types of polycyclic aromatic hydrocarbons (PAHs) from tea, fried food, and grilled food samples via gas chromatography flame ionization detector (GC-FID). One variable at a time (OVAT) and response surface methodology (RSM) were used for efficient optimization. The validation method showed a good coefficient of determination (R 2) ranging from 0.9901 to 0.9982 (n = 3) with linearity of 0.2 μg L−1–500 μg L−1. Detection and quantification limits were 0.06 µg L−1–0.32 µg L−1 and 0.18 µg L−1–0.97 µg L−1. Additionally, satisfactory reproducibility was attained with intra-day and inter-day precisions having RSD ranges of 3.6%–11.1%. The spiked recovery value of 16 PAHs in fried food, grilled food and tea samples obtained from the night market in Malaysia ranged from 80%–12%, respectively.

A Comprehensive Study on Outdoor Thermal Comfort in Arid Urban Environments through Microclimatic Analysis of Urban Density

Rapid urbanization across hot arid environments transforms local microclimates, yet linkages between density, layout, and outdoor thermal comfort remain inadequately characterized. This study investigates these correlations in the desert city of Biskra, Algeria. We conducted extensive in-situ measurement campaigns during peak summer and winter periods across six neighborhoods spanning low to high-rise density fabrics. We captured air temperature, humidity, and wind velocity to enable thermal comfort assessment via the Effective Temperature (ET) and Equivalent Temperature (TEK) stress indices. Index sensitivity to density metrics from 23–86% was explored through One-Variable-At-A-Time (OVAT) analysis. Results show marked summer comfort deterioration with rising density due to constrained ventilation. However, higher densities demonstrate superior winter warmth through wind blocking despite reduced sunlight exposure. Sharp nonlinear differences emerge between seasons. Precision density thresholds prove difficult to define conclusively given typological diversities. However, indicative ranges tied to hazards are identified, providing guidelines for informed climatic adaptation. This research delivers vital evidence to advance bioclimatic strategies for enhancing habitability amidst urban expansion across delicate hot deserts.

Grewia tenax bark extract mediated silver nanoparticles as an antibacterial, antibiofilm and antifungal agent

Grewia tenax plant possesses many medicinal qualities that can be harnessed for bio-applications via nanotechnology in a cost-effective and environment-friendly manner. The synthesised silver nanoparticles (GTB-AgNPs) from Grewia tenax bark extract were first detected by observing the change in colour from yellowish brown to dark brown and confirmed by UV–vis spectroscopy. UV–vis spectral analysis recorded the surface plasmon resonance at 420 nm. In the current research, several process parameters (time, temperature, concentration of AgNO3 and the ratio of extract to AgNO3) were adjusted by using one variable at a time (OVAT) approach. Spectroscopy accompanied by dynamic light scattering (DLS), x-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive x-ray (EDX) determines the size, nature, morphological variations and chemical constituents of GTB-AgNPs. The size range was found within 35−45 nm and the image clearly showed that the GTB-AgNPs were spherical in shape and well dispersed in nature. Zeta potential and Fourier-transform infrared spectroscopy (FTIR) were done to analyse GTB-AgNPs stability, dispersion and the biomolecules in aqueous bark extract liable for the bioreduction of silver particles. These GTB-AgNPs showed excellent antibacterial action against Gram-positive (S. aureus and B. subtilis) and Gram-negative bacteria (P. aeruginosa and E. coli) which was observed by disc diffusion assay. Congo red agar plate (CRA) assay effectively unveiled the antibiofilm proficiency of the particles. These studies displayed a reduction in bacterial sustainability and the formation of exopolysaccharides. Disc diffusion assay confirmed the antifungal competency against A. niger and C. albicans. SEM was performed to elucidate the intracellular breakage and morphological transformations in cells of Gram-positive bacteria and fungi after treatment with GTB-AgNPs. The current study, therefore, enlightened applications of GTB-AgNPs as an efficient antimicrobial agent and applicable substitute in the pharmaceutical area.

Optimization of laccase from Stenotrophomonas maltophilia E1 by submerge fermentation using coconut husk with its detoxification and biodecolorization ability of synthetic dyes

Enzymatic degradation of synthetic dyes holds an immense promise for addressing the environmental concerns associated with the textile and dye industries. This study aimed to isolate bacteria capable of producing laccase enzymes from an anthropogenic environment. Subsequently, viability of utilizing cost-effective agricultural residues as substrates for laccase production was assessed. Response Surface Methodology (RSM) and the One Variable at a Time (OVAT) approach was pursued for the optimization of laccase production, followed by pH and temperature stability, dye degradation and decolorization experiments, toxicological studies on the degraded dye metabolites. In results, laccase-producing bacterial strain was identified as Stenotrophomonas maltophilia strain E1 (S. maltophilia). Among variety of substrates, coconut husk exhibited optimal efficacy. In a statistical optimization study, it was found that S. maltophilia was capable of producing laccase 51.38 IU/mL, i.e., three times higher than the amount of laccase produced by unoptimized medium (16.7 IU/mL), and the enzyme activity was found to be steady at an acidic pH, and a mesophilic temperature range. The laccase obtained from S. maltophilia E1 demonstrated proficient dye decolorization capabilities, achieving a notable 92.1% reduction in Malachite green dye coloration at a concentration of 500 ppm. Gas chromatography–mass spectrometry (GC–MS) analysis of the decolorized derivatives of Malachite green revealed a conversion into a distinct compounds. Moreover, after undergoing laccase treatment, Malachite green exhibited decreased phytotoxic effects on Oryza sativa, pointing to enzymatic detoxification. Collectively, insights gained from the present study will contribute to the development of efficient enzymatic approaches for addressing the environmental pollution caused by synthetic dyes.Graphical

Mycosynthesis of silver nanoparticles from endophytic Aspergillus flavipes AUMC 15772: ovat-statistical optimization, characterization and biological activities

BackgroundMycosynthesis of silver nanoparticles (SNPs) offers a safe, eco-friendly, and promising alternative technique for large-scale manufacturing. Our study might be the first report that uses mycelial filtrate of an endophytic fungus, Aspergillus flavipes, for SNPs production under optimal conditions as an antimicrobial agent against clinical multidrug-resistant (MDR) wound pathogens.ResultsIn the present study, among four different endophytic fungi isolated from leaves of Lycium shawii, the only one isolate that has the ability to mycosynthesize SNPs has been identified for the first time as Aspergillus flavipes AUMC 15772 and deposited in Genebank under the accession number OP521771. One variable at a time (OVAT) and Plackett Burman design (PBD) were conducted for enhancing the production of mycosynthesized SNPs (Myco-SNPs) through optimization using five independent variables. The overall optimal variables for increasing the mycosynthesis of SNPs from mycelial filtrate of A. flavipes as a novel endophytic fungus were a silver nitrate concentration of 2 mM, a pH of 7.0, an incubation time of 5 days, and a mycelial filtrate concentration of 30% in dark conditions. UV–visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FT-IR), X-ray spectroscopy (XRD), Transmission electron microscopy (TEM), and Selected-Area Electron Diffraction (SAED) patterns were used to characterize Myco-SNPs, which showed the peak of absorbance at 420 nm, and FTIR showed the bands at 3426.44, 2923.30, 1681.85, 1552.64, and 1023.02 cm-1, respectively, which illustrated the presence of polyphenols, hydroxyl, alkene, nitro compounds, and aliphatic amines, respectively. The XRD pattern revealed the formation of Myco-SNPs with good crystal quality at 2θ = 34.23° and 38.18°. The TEM image and SAED pattern show the spherical crystalline shape of Myco-SNPs with an average size of 6.9232 nm. High antibacterial activity of Myco-SNPs was recorded against MDR wound pathogens as studied by minimum inhibitory concentrations ranging from 8 to 32 µg/mL, time kill kinetics, and post-agent effects. Also, in vitro cell tests indicated that Myco-SNPs support the cell viability of human skin fibroblast cells as a nontoxic compound.ConclusionThe obtained results revealed the successful production of Myco-SNPs using the mycelial filtrate of A. flavipes, which may be a promising nontoxic alternative candidate for combating MDR wound pathogens.

Sugar-based natural deep eutectic solvent ultrasound-assisted extraction for the determination of polyphenolic compounds from various botanical sources

In this study, a novel ultrasound-assisted extraction method utilizing natural deep eutectic solvent (NADES) was developed for the efficient extraction of 20 polyphenolic compounds from various botanical sources, followed by HPLC–DAD detection. By mixing choline chloride as a hydrogen bond acceptor (HBA) and various sugars, such as arabinose, fructose, galactose, trehalose and raffinose, as well as one sugar alcohol (mannitol), in a range of molar ratios, 21 different DESs were prepared and tested. The important parameters influencing the extraction efficiency were studied and optimized using the one-variable-at-a-time (OVAT) method on Picea abies (L.) Karst. needles as a model sample. The optimal conditions were found to be NADES formed by mixing choline chloride and raffinose in a 1:1 M ratio containing 30% water, extraction temperature 25 °C, extraction time 30 min, ultrasound power 60%. The calibration plots were linear from 0.50 to 50 μg mL−1 from standard for the majority of the target analytes, and the instrumental LOD and LOQ values were found to be in the range 0.02–0.19 μg mL−1 and 0.07–0.64 μg mL−1, respectively. The extraction efficiency of the NADES was compared with the efficiency of classical solvents, such as water or methanol, and the NADES revealed a remarkable increase of extraction yield. The newly developed extraction method was successfully applied for the analysis of diverse range of plant materials, encompassing coniferous plants such as Picea abies (L.) Karst, Pinus sylvestris L., and leafy trees Quercus robur L., Ulmus glabra Hudson and Brassica napus L. thereby revealing the polyphenolic profiles of different botanical species.

Optimisation of β-Glucosidase Production in a Crude Aspergillus japonicus VIT-SB1 Cellulase Cocktail Using One Variable at a Time and Statistical Methods and its Application in Cellulose Hydrolysis.

Pulp and paper mill sludge (PPMS) is currently disposed of into landfills which are reaching their maximum capacity. Valorisation of PPMS by enzymatic hydrolysis using cellulases is an alternative strategy. Existing commercial cellulases are expensive and contain low titres of β-glucosidases. In this study, β-glucosidase production was optimised by Aspergillus japonicus VIT-SB1 to obtain higher β-glucosidase titres using the One Variable at a Time (OVAT), Plackett Burman (PBD), and Box Behnken design (BBD)of experiments and the efficiency of the optimised cellulase cocktail to hydrolyse cellulose was tested. β-Glucosidase production was enhanced from 0.4 to 10.13 U/mL, representing a 25.3-fold increase in production levels after optimisation. The optimal BBD production conditions were 6 days of fermentation at 20 °C, 125 rpm, 1.75% soy peptone, and 1.25% wheat bran in (pH 6.0) buffer. The optimal pH for β-glucosidase activity in the crude cellulase cocktail was (pH 5.0) at 50 °C. Optimal cellulose hydrolysis using the crude cellulase cocktail occurred at longer incubation times, and higher substrate loads and enzyme doses. Cellulose hydrolysis with the A. japonicus VIT-SB1 cellulase cocktail and commercial cellulase cocktails resulted in glucose yields of 15.12 and 12.33 µmol/mL glucose, respectively. Supplementation of the commercial cellulase cocktail with 0.25 U/mg of β-glucosidase resulted in a 19.8% increase in glucose yield.

Coagulation–flocculation of aquaculture effluent using biobased flocculant: From artificial to real wastewater optimization by response surface methodology

Coagulation–flocculation is currently the best practice for aquaculture effluent treatment, and biobased compounds are emerging as coagulant/flocculants. This study aimed to characterize the bioflocculant produced from Serratia marcescens and applied it to treat artificial turbid water (kaolin substrate) and real aquaculture effluent using the combination of one variable at a time (OVAT) and response surface methodology (RSM) analyses. The bioflocculant produced by S. marcescens was characterized as anionic flocculant with isoelectric point at pH 1.7 and 13.3. At pH 7, its protein content was 1.3 μg/mL, and its total carbohydrate level was 0.53 mg/L. The bioflocculant consisted of various carboxylic acids and enzyme intermediates, indicating the presence of polysaccharides and protein. Comparison of optimized treatment conditions between OVAT and RSM showed that rapid mixing speed, slow mixing time, and sedimentation time were the most influential factors for coagulation–flocculation. The aquaculture effluent required lower rapid mixing speed (125 rpm) and shorter sedimentation time (39 min) than artificial wastewater (160 rpm and 67 min, respectively). The low performance of the bioflocculant in treating aquaculture effluent was due to the more complex characteristics of real aquaculture effluent compared with those of kaolin substrate. Environmental implicationsThe characterization of bioflocculant produced by Serratia marcescens in terms of its protein level, total carbohydrate content, and isoelectric point has never been reported. The obtained results may provide an insight into the potential of this compound to substitute widely used chemical flocculants with reliable performance. The findings may also be used as a basis to upscale coagulation–flocculation from being applied to artificial wastewater in the laboratory to treating real wastewater, especially with the use of biobased compounds.

Revolutionizing Drug Removal: Green Magnetic Nanoparticles Functionalized with Hydrophobic Deep Eutectic Solvents for Anti-Inflammatory Drug Adsorption

Non-steroidal anti-inflammatory medications are popular pharmaceutical and personal products due to their anti-inflammatory properties and ease of availability. However, the complex structure of these pollutants and their existence at low concentration makes them difficult to trace, posing a major challenge in their removal from aquatic environments. Therefore, the disposal and treatment of these emerging compounds have become a key concern in water treatment. In this study, new hydrophobic deep eutectic solvents (HDES) were successfully prepared using a cheap and simple component consist of decanoic acid and 2-pentanol as the hydrogen bond acceptor and hydrogen bond donor, respectively. The prepared HDES was functionalized onto magnetic nanoparticles, namely Fe3O4@HDES, as an efficient adsorbent for diclofenac and ibuprofen. Based on the findings of the cytocompatibility study, HDES offers new possibilities for safe distribution and application. The optimum adsorption conditions, including solution pH, adsorbent amount, and sample volume, were determined using the Taguchi experimental design. The One-Variable-at-a-Time (OVAT) method was used to determine the other parameters, such as the types of adsorbents, contact time, initial concentration, and initial temperature. Analysis of Variance (ANOVA) revealed that the solution pH played the most significant role in the adsorption of both diclofenac and ibuprofen, followed by the adsorbent amount and sample volume. The characterization involved several tools, including Fourier transform-infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating-sample magnetometer (VSM), and Brunauer-Emmett-Teller (BET) analysis. Both diclofenac and ibuprofen adsorption followed chemisorption, and the process was feasible, spontaneous, and exothermic. Molecular docking also supported the choice of HDES as a functionalized agent by suggesting a schematic diagram of the energetically advantageous adsorption mechanism, which was in good accord with the experimental findings. The interaction between the adsorbent and adsorbates via hydrophobic interaction and hydrogen bonding was found to be accountable for adsorption. The results indicated that green synthesized Fe3O4@HDES offers a possible sustainable and green benefit through the adsorption of diclofenac and ibuprofen from contaminated water as an adsorbent.