Physicochemical Characteristics Research Articles

Assessment of the chemical composition of buriti (Mauritia flexuosa Liliopsida) and cassava (Manihot esculenta Crantz) residues and their possible application in the bioproduction of coconut aroma (6 pentyl-α-pyrone).

This work aimed to define strategies to increase the bioproduction of 6 pentyl-α-pyrone (bioaroma). As first strategy, fermentations were carried out in the solid state, with agro-industrial residues: Mauritia flexuosa Liliopsida. and Manihot esculenta Crantz in isolation, conducting them with different nutrient solutions having Trichoderma harzianum as a fermenting fungus. Physicochemical characterizations, centesimal composition, lignocellulosic and mineral content and antimicrobial activity were required. Fermentations were conducted under different humidification conditions (water, nutrient solution without additives and nutrient solutions with glucose or sucrose) for 9days. Bioaroma was quantified by gas chromatography, assisted by solid-phase microextraction. The results showed the low production of this compound in fermentations conducted with sweet cassava (around 6ppm (w/w)). The low bioproduction with sweet cassava residues can probably be related to its starch-rich composition, homogeneous substrate, and low concentration of nutrients. Already using buriti, the absence of aroma production was detected. Probably the presence of silicon and high lignin content in buriti minimized the fungal activity, making it difficult to obtain the aroma of interest. Given the characteristics presented by the waste, a new strategy was chosen: mixing waste in a 1:1 ratio. This fermentation resulted in the production of 156.24ppm (w/w) of aroma using the nutrient solution added with glucose. This combination, therefore, promoted more favorable environment for the process, possibly due to the presence of fermentable sugars from sweet cassava and fatty acids from the buriti peel, thus proving the possibility of an increase of around 2500% in the bioproduction of coconut aroma.

Pharmaceutical/Biomedical Applications of Electrospun Nanofibers - Comprehensive Review, Attentive to Process Parameters and Patent Landscape.

Nanotechnology is a new science and business endeavour with worldwide economic benefits. Growing knowledge of nanomaterial fabrication techniques has increased the focus on nanomaterial preparation for various purposes. Nanofibers are one-dimensional nanomaterials having distinct physicochemical properties and characteristics. Nanofibers are nanomaterial types with a cross-sectional dimension of tens to hundreds of nanometres. They may create high porosity mesh networks with significant interconnections among pores, making them suitable for advanced applications. Electrospinning stands out for its ease of use, flexibility, low cost, and variety among the approaches described in the literature. The most common method for making nanofibers is electrospinning. This article extensively describes and summarizes the impact of various process variables on the fabrication of nanofibers. Special attention has been given to scientific and patent prospection to confirm the research interests in nanofibers.

3D Electrospun nanofiber sponges of insect chitosan/pullulan/citric acid embedded with ZnMOF in situ for enhanced healing of MRSA-infected wounds

In biomedicine, one of the major challenges is effectively promoting wound healing of bacterial infections. Current wound dressings (e.g., gauze and bandages) are far from meeting the needs of the population as they lack various bioactivities to promote wound healing (including hemostasis, antimicrobial, anti-inflammatory, promotion of tissue regeneration, etc.) and are not biodegradable. In this study, we prepared an insect chitosan/pullulan/citric acid three-dimensional, layered electrospun nanofiber sponge embedded with ZnMOF in situ (3D-ZnMOF) and used it to promote MRSA-infected wound healing. The fabrication method and physicochemical characteristics of 2D nanofiber membranes and 3D nanofiber sponges were thoroughly assessed. SEM-EDS, XPS, XRD, and FT-IR were used to characterize the 3D-ZnMOF sponges, and the release behavior of zinc ions was examined. Experiments conducted both in vitro and in vivo demonstrated the hemostatic characteristics, biocompatibility, and antibacterial activity of 3D-ZnMOF sponges. 3D-ZnMOF sponges showed the ability to promote wound contraction, accelerate collagen deposition, inhibit inflammatory factors, and promote angiogenesis in an MRSA-infected rat whole-skin wound model. Consequently, 3D-ZnMOF nanofiber sponges offer a great deal of promise for accelerating the healing of wounds infected with drug-resistant bacteria.

Isotype BiVO4 Heterostructure and the Effect of Photo-Sono Induced Electron-Hole Pair

Owing to its suitable energy band and strong catalytic capacity, BiVO4 has received extensive attention in photocatalysis. Here, we suggest a straightforward approach to address the challenges of insufficient compatibility, poor charge transport characteristics, and limited surface adsorption properties commonly found in traditional BiVO4 photocatalysts. A heterojunction BiVO4 structure is developed by incorporating two distinct crystal phases within a single semiconducting material. A facile hydrothermal procedure is used to synthesize distinct crystalline phases of BiVO4 photocatalysts, viz., tetragonal, monoclinic, and monoclinic/tetragonal heterophase. The physicochemical characteristics of the pristine and isotype BiVO4 heterojunctions were characterized using various techniques. The photocatalytic activity of BiVO4 samples was examined by monitoring the degradation of rhodamine B (RhB). In order to boost the degradation reaction, ultrasonic sound waves are employed within the reaction medium. The present study examined the photocatalytic, sonocatalytic, and sonophotocatalytic activity of BiVO4 microcrystals in relation to the degradation of RhB dye. The results show that the crystalline phases of BiVO4 samples significantly influence the behaviour of photo-sono-induced charges. An interface in the monoclinic/tetragonal heterophase creates a spatial environment that facilitates charge transfer and enhances the separation of photo-sono-induced electron-hole pairs. The paper extensively examines the correlation between the behaviour of photo-sono-induced charge carriers and the level of sonophotocatalytic activity. This would provide greater insight into the intrinsic reasons for the enhancement in sonophotocatalytic activity.

Effect of Prebiotic Supplementation on Probiotic Viability and Physicochemical Characteristics of Fermented Coconut Water with Bifidobacterium longum

Background: Probiotics and prebiotics are functional ingredients that provide health benefits to consumers but they are mainly incorporated in dairy products. Designing a non-dairy product in which probiotics and prebiotics would be incorporated would allow more consumers to benefit from their advantages. Objective: This study investigated the effect of supplementation of two different prebiotics, fructooligosaccharide (FOS) and inulin, on the viability of Bifidobacterium longum ATCC BAA-999 in coconut water. Methods: Two concentrations of prebiotics used were 1% and 2%. The physicochemical characteristics of fermented coconut water with B. longum for 9 h at 37oC and during refrigerated storage at 4oC for 2 weeks were analyzed. The viability of B. longum in fermented coconut water was maintained above the recommended therapeutic level (7 log CFU/mL) with or without supplementation with prebiotics. Results: Most distinct changes in colour (∆E > 3) occurred in fermented coconut water compared to unfermented coconut water. An increase in the total soluble solids was also observed in fermented coconut water with the increase in the concentration of prebiotics. There were no significant changes in the clarity, pH, and concentrations of shikimic and malic acids in the fermented coconut water with or without supplementation with prebiotics over the 2 weeks of storage. Acetic acid production was observed in the fermented coconut water with the highest acetic acid production in the fermented coconut water supplemented with 1% FOS after 2 weeks of storage. Conclusion: This study demonstrated the potential use of coconut water as a medium to produce a probiotic drink.

Docking, Synthesis, and In vitro Anti-depressant Activity of Certain Isatin Derivatives.

In vitro, the molecular docking method has been suggested for estimating the biological affinity of the pharmacophores with physiologically active compounds. It is the latter stage in molecular docking, and the docking scores are examined using the AutoDock 4.2 tool program. The chosen compounds can be evaluated for in vitro activity based on the binding scores, and the IC50 values can be computed. The purpose of this work was to create methyl isatin compounds as potential antidepressants, compute physicochemical characteristics, and carry out docking analysis. The protein data bank of the RCSB (Research Collaboratory for Structural Bioinformatics) was used to download the PDB structures of monoamine oxidase (PDB ID: 2BXR) and indoleamine 2,3-dioxygenase (PDB ID: 6E35). Based on the literature, methyl isatin derivatives were chosen as the lead chemicals. By determining their IC50 values, the chosen compounds were tested for in vitro anti-depressant activity. The binding scores for the interactions of SDI 1 and SD 2 with indoleamine 2,3 dioxygenase were found to be -10.55 kcal/mol and -11.08 kcal/mol, respectively, while the scores for their interactions with monoamine oxidase were found to be -8.76 kcal/mol and -9.28 kcal/mol, respectively, using AutoDock 4.2. The relationship between biological affinity and pharmacophore electrical structure was examined using the docking technique. The chosen compounds were tested for their ability to inhibit MAO, and the IC50 values for each were found to be 51.20 and 56, respectively. This investigation has identified many novel and effective MAO-A inhibitors from the family of chemicals known as methyl isatin derivatives. Lead optimization was applied to the SDI 1 and SDI 2 derivatives. The superior bioactivity, pharmacokinetic profile, BBB penetration, pre-ADMET profiles, such as HIA (human intestinal absorption) and MDCK (Madin-Darby canine kidney), plasma protein binding, toxicity assessment, and docking outcomes, have been obtained. According to the study, synthesised isatin 1 and SDI 2 derivatives exhibited a stronger MAO inhibitory activity and effective binding energy, which may help prevent stress-induced depression and other neurodegenerative disorders caused by a monoamine imbalance.

Engineering and physicochemical characterization of a novel, stable, symmetric bispecific antibody with dual target-binding using a common light chain.

Bispecific antibodies (BsAbs) have emerged as a major class of antibody therapeutics owing to their substantial potential in disease treatment. While several BsAbs have been successfully approved in recent years, ongoing development efforts continue to focus on optimizing various BsAbs tailored to particular antigens and action mechanisms, aiming to achieve favorable physicochemical properties. BsAbs generally encounter challenges due to their unfavorable physicochemical characteristics and poor manufacturing efficiencies, highlighting the need for optimization to achieve reliable productivity and developability. Herein, we describe the development of a novel symmetric BsAb, REGULGENT™ (N-term/C-term), comprising two Fab domains, using a common light chain. The heavy chain fragment encoded two antigen-binding determinants in one chain. The design and production of REGULGENT™ (N-term/C-term) are simple owing to the use of the same light chain, which does not induce heavy and light chain mispairing, frequently observed with the asymmetric BsAb format. REGULGENT™ (N-term/C-term) exhibited high expression and low aggregation characteristics during cell culture and stress treatment under low pH conditions. Differential scanning calorimetric data indicated that REGULGENT™ molecules had high conformational stability, similar to that of stabilized monoclonal antibodies. Surface plasmon resonance data showed that REGULGENT™ (N-term/C-term) could bind to two antigens simultaneously and exhibited a high affinity for two antigens. In summary, the symmetric BsAb format of REGULGENT™ confers its desirable IgG-like physicochemical properties, thus making it an excellent candidate for commercial development. The findings demonstrate a novel BsAb with substantial development potential for clinical applications.

Alkali pretreatment-assisted catalytic pyrolysis of waste cellulose acetate for selective preparation of levoglucosenone

With the increasing demand for cellulose acetate (CA) in industrial and daily applications, the disposal of its waste has emerged as an environmental concern. In this study, a novel and sustainable method for value-added utilization of waste CA was proposed, which involved NaOH pretreatment and subsequent catalytic pyrolysis using phosphoric acid-activated carbon (PAC) to prepare levoglucosone (LGO). The effects of pretreatment temperatures and NaOH concentrations on the physicochemical characteristics of CA were thoroughly investigated. Furthermore, the pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) experiments were conducted to methodically assess the impacts of both pretreatment and pyrolysis conditions on the production of LGO. The results indicated that NaOH pretreatment could effectively hydrolyze the ester bonds in CA, leading to the removal of acetyl groups and a decrease in thermal stability. At a pretreatment temperature of 40°C, a NaOH concentration of 0.5mol/L, a catalyst/sample ratio of 1/3, and a pyrolysis temperature of 400°C, the LGO yield could reach 11.52wt%, much higher than that obtained from catalytic pyrolysis of CA (2.70wt%). This study provides an efficient method for treating waste CA and demonstrates its potential for conversion into high-value chemicals, laying a solid foundation for the green recycling of waste plastics.

Agronomic and Physicochemical Characterization of Gamma Irradiation on M4 Cowpea (Vigna unguiculata [L.] Walp.) Mutants

Agronomic and Physicochemical Characterization of Gamma Irradiation on M4 Cowpea (Vigna unguiculata [L.] Walp.) Mutants

Physico-chemical and nutritional characteristics of 12 varieties of cassava (Manihot esculenta Crantz, 1766) grown in the Republic of Guinea

Cassava is a distinctive contributor to food security and a source of income for smallholder farmers. Despite the importance of this agricultural product, very little data is available in Guinea, especially concerning the varieties grown and their nutritional composition. The aim of this research was to study the physico-chemical and nutritional characteristics of 12 varieties of cassava grown in Guinea with a view to selecting varieties that could be used to produce a <<Gari>> of better quality. Cassava tubers were collected in 6 regions in Guinea. The physico-chemical analyses were carried out on the pH and moisture content of the cassava paste from each of the 12 varieties, while the nutritional quality was determined on the basis of the composition of the varieties in carbohydrates, proteins, lipids and minerals. In general, pH values ranged from 6.29 to 7.29 while moisture levels ranged from 51.64% to 58.94%. In addition, all the varieties analysed were those rich in carbohydrates (with levels between 42.36% and 51.17%) but low in fat (values between 0.30% and 3.56%). On the other hand, three varieties, namely Farawoulen, Konko and Samouya, are the richest in protein with values of 8.05%, 5.48% and 4.23% respectively. In short, these cassava varieties produced in Guinea could be used, taking into account their biochemical composition, in future gari production work.

Nano-theranostics: A novel platform in drug therapy

A fundamental component of customized medicine, theranostics is a therapy approach that combines therapeutics and diagnostics with the goal of increasing drug efficacy and safety while also monitoring treatment response. It will require significant advancements in predictive medicine. Theranostics is linked to tailored drug administration based on test results as well as a diagnostic that screens patients for potential adverse drug reactions. Early diagnosis and treatment have benefited from the designed nanoparticles with unique physicochemical characteristics. This allows treatments to be delivered and the detection method to be employed concurrently, not just before or after treatment but throughout the entire regimen. The development of nanotechnology presents more opportunities for theranostics applications using nanoparticle engineering, and it has demonstrated encouraging outcomes, particularly in cancer therapy when compared with conventional treatments.

Antibacterial and cytocompatible silver coating for titanium Boston Keratoprosthesis

The Boston Keratoprosthesis (BKPro) serves as a medical solution for restoring vision in complex cases of corneal blindness. Comprising a front plate made of polymethylmethacrylate (PMMA) and a back plate of titanium (Ti), this device utilizes the beneficial biomaterial properties of Ti. While BKPro demonstrates promising retention rates, infection emerges as a significant concern that impacts its long-term efficacy. However, limited research exists on enhancement of BKPros through intrinsic infection-preventing mechanisms. In this regard, metal ions, especially the well-known Ag+ ions, are a promising alternative to obtain implants with innate antibacterial properties. However, little information is available about the effects of Ag in corneal tissue, especially within human corneal keratocytes (HCKs). In this work, an electrodeposition treatment using a constant pulse is proposed to attach Ag complexes onto rough Ti surfaces, thus providing antibacterial properties without inducing cytotoxicity. Complete physicochemical characterization and ion release studies were carried out with both control and Ag-treated samples. The possible cytotoxic effects in the short and long term were evaluated in vitro with HCKs. Moreover, the antibacterial properties of the silver-treated surfaces were tested against the gram-negative bacterial strain Pseudomonas aeruginosa and the gram-positive strain Staphylococcus epidermidis, that are common contributors to infections in BKPros. Physicochemical characterization confirmed the presence of silver, predominantly in oxide form, with low release of Ag+ ions. Ag-treated surfaces demonstrated no cytotoxicity and promoted long-term proliferation of HCKs. Furthermore, the silver-treated surfaces exhibited a potent antibacterial effect, causing a reduction in bacterial adhesion and evident damage to the bacterial cell walls of P. aeruginosa and S. epidermidis. The low release of Ag+ ions suggested reactive oxygen species (ROS)-mediated oxidative stress imbalance as the bactericidal mechanism of the silver deposits. In conclusion, the proposed electrodeposition technique confers antibacterial protection to the Ti backplate of BKPro, mitigating implant-threatening infections while ensuring non-cytotoxicity within the corneal tissue.

"Straw in the Clay Soil" Strategy: Anticarbon Corrosive Fluorine-Decorated Graphene Nanoribbons@CNT Composite for Long-Term PEMFC.

Carbon corrosion poses a significant challenge in polymer exchange membrane fuel cells (PEMFCs), leading to reduced cell performance due to catalyst layer degradation and catalyst detachment from electrodes. A promising approach to address this issue involves incorporating an anticorrosive carbon material into the oxygen reduction reaction (ORR)electrode, even in small quantities (≈3wt% in electrode). Herein, the successful synthesis of fluorine-doped graphene nanoribbons (F-GNR) incorporated with graphitic carbon nanotubes (F-GNR@CNT), demonstrating robust resistance to carbon corrosion is reported. By controlling the synthesis conditions using an exfoliation method, the properties of the composite are tailored. Electronic structural studies, employing density functional theory (DFT) calculations, to elucidate the roles of fluorine dopants and graphitic carbon nanotubes (CNTs)in mitigating carbon corrosion are conducted. Physicochemical and electrochemical characterization of F-GNR@CNT reveal its effectiveness as a cathode additive at the single-cell scale. The addition of F-GNR@CNT to the Pt/C cathode improves durability by enhancing carbon corrosion resistance and water management, thus mitigating the flooding effect through tailored surface properties. Furthermore, advanced impedance analysis using a transmission line model is performed to gain insights into the internal resistance and capacitive properties of electrode structure.

Comprehensive Analysis of Cetuximab Critical Quality Attributes: Impact of Handling on Antigen-Antibody Binding

Background/Objectives: Cetuximab, formulated in Erbitux® (5 mg/mL), is a therapeutic monoclonal antibody (mAb) widely used in several cancer treatments. Currently, there is insufficient knowledge about the behavior of cetuximab with regard to the risk associated with its routine handling or unintentional mishandling in hospitals. Forced degradation studies can simulate these conditions and provide insights into the biophysical and biochemical properties of mAbs. Methods: In this study, we conducted a deep physicochemical and functional characterization of the critical quality attributes of cetuximab in control samples and under controlled degraded conditions, including freeze–thaw cycles, heat, agitation, and light exposure. To achieve this purpose, we used a set of proper analytical techniques, including CD, IT-FS, DLS, SE/UHPLC-UV, UHPLC-MS/MS, and ELISA, to check functionality based on antigen–antibody binding. Results: The results revealed that light exposure was the stress stimuli with the greatest impact on the drug product, leading to the formation of non-natural oligomers, fragmentation, and oxidation of methionine residues. Additionally, cetuximab (Erbitux®, 5 mg/mL) showed a tendency to aggregate when submitted to 60 °C for 1 h. In terms of functionality, cetuximab (Erbitux®, 5 mg/mL) samples were found to be affected when subjected to freeze–thaw cycles, 60 °C (1 h), and when exposed to light (daylight with room temperature excursion and accelerated light exposure). Conclusions: Thus, we suggest that Erbitux® (5 mg/mL) should be shielded from these environmental conditions, as they compromise both the safety and efficacy of the drug product.

Relationship between consumer acceptance, sensory characteristics, and physicochemical characteristics of "Fuji" apples from different origins.

This study examines the acceptance of young Chinese consumers for different "Fuji" apples, focusing on their sensory characteristics and physicochemical foundations. The sensory attributes of the samples were evaluated using a combination of static descriptive analysis (DA) and temporal check-all-that-apply fading (TCATA-fading) methods. Furthermore, the volatile compounds, soluble sugars, organic acids, and textural parameters of the samples were analyzed. The findings revealed that participants favored apples that were perceived as "sweet," "crunchy," "juicy," and "aromatic." The results from the DA indicated that certain sensory attributes, such as "sweet," "vanilla," "honey," and "pear" positively influenced acceptance, while attributes like "sour," "hard," and "grass" had a negative impact. The findings from both the DA and TCATA-fading methods were consistent with each other. In terms of dynamic evaluation, sweetness, and sourness were the initial perceptions, followed by a range of other flavors. Notably, our data suggested that sweetness perception could be enhanced by attributes such as "honey" and "banana." Additionally, the sugar-acid ratio and specific volatile compounds, including hexanal, (E)-2-hexenal, β-damascenone, butyl acetate, and propyl 2-methylbutyrate, were found to influence the perception of sweetness in apples. PRACTICAL APPLICATION: This study helps to understand the effect of different origins on the acceptance of "Fuji" apples and to know the sensory and material basis for the emergence of such differences. It is beneficial for growers and marketers to improve 'Fuji' apples.

Anti-Coronavirus Activity of Chitosan-Stabilized Liposomal Nanocarriers Loaded with Natural Extracts from Bulgarian Flora

Disease’s severity, mortality rates, and common failures to achieve clinical improvement during the unprecedented COVID-19 pandemic exposed the emergency need for new antiviral therapeutics with higher efficacy and fewer adverse effects. This study explores the potential to encapsulate multi-component plant extracts in liposomes as optimized delivery systems and to verify if they exert inhibitory effects against human seasonal betacoronavirus OC43 (HCoV-OC43) in vitro. The selection of Sambucus nigra, Potentilla reptans, Allium sativum, Aesculus hippocastanum, and Glycyrrhiza glabra L. plant extracts was based on their established pharmacological and antiviral properties. The physicochemical characterization of extract-loaded liposomes was conducted by DLS and electrokinetics. Encapsulated amounts of the extract were evaluated based on the total flavonoid content (TFC) and total polyphenol content (TPC) by colorimetric methods. The BALB 3T3 neutral red uptake (NRU) phototoxicity/cytotoxicity assay was used to estimate compounds’ safety. Photo irritation factors (PIFs) of the liposomes containing extracts were <2 which assigned them as non-phototoxic substances. The antiviral capacities of liposomes containing medicinal plant extracts against HCoV-OC43 were measured by the cytopathic effect inhibition test in susceptible HCT-8 cells. The antiviral activity increased by several times compared to “naked” extracts’ activity reported previously. A. hippocastanum extract showed 16 times higher inhibitory properties reaching a selectivity index (SI) of 58.96. Virucidal and virus-adsorption effects were investigated using the endpoint dilution method and ∆lgs comparison with infected and untreated controls. The results confirmed that nanoparticles do not directly affect the viral surface or cell membrane, but only serve as carriers of the active substances and the observed protection is due solely to the intracellular action of the extracts.

Invasion stage of the exotic snail Melanoides tuberculata related to environmental and biological factors in a subtropical river drainage

The mollusks represent the main invasive taxon of the freshwater ecosystem in North America. Environmental degradation may increase the susceptibility of the ecosystem to invasion and favor the abundance and density increment in some benthic mollusks. Melanoides tuberculata is a snail native from Africa and Asia that was introduced in Mexico in the sixties through aquarium activities. Its reproduction by parthenogenesis, fast growth, longevity, omnivore habits, and wide tolerance to pollution and environmental stressors, confers to this snail great capability like invasive species. However, the information concerning the relationships between the invasion stage of this exotic snail and environmental and biological variables is still unknown. This study aimed to document the establishment of several new registered populations of M. tuberculata in subtropical river drainage in central Mexico, since at least 10 years ago, and its relationship with indicator variables of environmental degradation. We visited 15 localities during the dry season in 2016 and 2022. At each study site, the macroinvertebrate assemblages were collected, and physical variables of habitat and physicochemical water characteristics were measured. In addition, the biological condition was assessed using aquatic macroinvertebrate assemblages. Each individual of M. tuberculata was counted and measured. The abundance and density of the snail with physical, chemical, and biological variables were correlated, and further multivariate analyses were performed to confirm these relationships. We demonstrated a positive relationship between the presence, abundance, and density of M. tuberculata with environmental variables that are indicators of degradation of physical attributes such as water flow alterations and loss of habitat heterogeneity in 2016 and 2022. We supported the hypothesis that anthropic habitat degradation can favor the invasion of M. tuberculata.

Investigating the Impact of Moisture Levels on Structural Alterations and Physicochemical Properties of Cassava Flour through Extrusion: A Comprehensive Study.

The extrusion process, a vital technique for starch modification, is notably influenced by the moisture content (MC). This study aimed to elucidate the effect of varying MC levels (18, 22, 26, and 30%) on the structural and physicochemical characteristics of cassava flour during extrusion. Extrusion resulted in the fraction of degree of polymerization 13‒24, degree of branching, and molecular weight increased with increasing MC, with values of above indexes being 32.29%, 1.05%, and 1.21 × 105 g/mol, respectively, at a MC of 18%. This suggested that the degradation of amylopectin and amylose. Additionally, there was an increase in rapidly digestible starch (RDS) and a decrease in slowly digestible starch (SDS) in the extrudates in comparison to the native cassava flour. The extrusion of cassava flour at 18% MC exhibited the highest levels of RDS and SDS, reaching 64.52% and 4.06%, respectively. These findings indicated that low moisture extrusion could be a more effective method for disrupting the structure of cassava starch and enhancing the digestibility of cassava flour, offering valuable insights for the optimized use of cassava extrudates in various applications.

Studying the Characteristics of Tank Oil Sludge

Oil sludge is one of the main pollutants generated by the oil industry. Due to serious pollution and increasing oil production, problems arise every year in the effective treatment of oil sludge. The current study examines the composition and physicochemical characteristics of oil sludge, as well as traditional and new methods for processing oil sludge. With the tightening of environmental protection requirements, oil sludge quality reduction, recycling, and harmless treatment technologies will become necessary in the future. The primary task was to determine the composition of tank oil sludge, separate it from mechanical impurities, and study the influence of ultrasonic treatment and subsequent atmospheric distillation on the extract. The separation of the concentrate and the composition of the tank oil sludge, using an extracted mixture of hexane and benzene, are considered. The use of modern SEM methods, elemental analysis, NMR analysis, IR, ultrasound, and GC–mass spectrometry made it possible to characterize the organic part of reservoir oil sludge and its distillation products. First, 300 g of tank oil sludge was preheated and mixed with 300 mL of solvent (hexane:benzene = 1:1). After mixing with the solvent, the result mixture was filtered. Then, it was placed in an ultrasonic bath and exposed to ultrasound at a frequency of 100 kHz for 30 min. After processing, it was extracted in a Soxhlet apparatus at a temperature of 65 °C to isolate the extract. The resulting extract was analyzed on a gas chromatograph with mass detection. The composition of the extract was as follows (in %): hexane—83.99; total hydrocarbon isomers—7.12; n-hydrocarbons—2.52; benzene—6.37%. At a temperature of 85 °C, the benzene yield was 65.85%. It has been established that the fractions obtained through the distillation of oil sludge at temperatures of 65–85 °C have improved dissolving capacity. It has also been shown that the use of these fractions promotes an increase in the content of hydrocarbon isomers by 12–13% in the extract composition.

Bioenergy potential from Ecuadorian lignocellulosic biomass: Physicochemical characterization, thermal analysis and pyrolysis kinetics

Lignocellulosic biomass offers a sustainable and renewable method for producing high-quality fuels and value-added chemicals. In this study, residues from peach palm (top, inner sheath, and meristem), sugarcane (top), and pineapple (mother plant) were characterized based on their physicochemical properties and thermal degradation behavior to estimate their bioenergy potential. The biomass residue kinetic constraints were analyzed using three isoconversional models: the Flynn–Wall–Ozawa (FWO), Kissinger–Akahira–Sunose (KAS), and differential Friedman (DF) models. Physicochemical characterization showed the peach palm top's notably high cellulose content of 35.71 ± 0.47 % wt. Calorific values of the residues ranged from 13.73 ± 0.08 to 16.91 ± 0.90 MJ kg−1. X-ray diffraction analysis indicated the carbonaceous and crystalline nature of the biomass residues. Mean activation energy values ranged from 105.02 to 370.10 kJ mol−1 for KAS, 111.50–360.99 kJ mol−1 for FWO, and 108.60–360.27 kJ mol−1 for DF. Finally, thermodynamic analysis revealed the endothermic nature of the pyrolysis process across the entire conversion range for the samples. Overall, these samples demonstrate major potential as feedstock for biorefineries and the development of Ecuador's circular economy.