Physiochemical Characterization Research Articles

Development of microbial fuel cell for wastewater treatment and electricity generation using domestic wastes

Background: The energy crisis is a growing problem around the world, requiring the creation of alternative energy sources that can generate less carbon dioxide and benefit the ecosystem. Reutilization of wastewater is becoming the emerging energy solution. Wastewater contains a large amount of organic matter that can be oxidized in microbial fuel cells (MFCs) to produce electricity. MFCs use biodegradable materials to create energy in the presence of microorganisms. Methods: Purposive sampling technique was employed to collect samples from critical polluting sources. The samples were certainly maintained in a refrigerator at 4°C. Several mixes for sample were prepared and tested analytically- for physio-chemical and bacteriological characterizations of each substrate status at pre- and post-treatment stages. Electricity generating capacity of MFCs that employing different substrates was investigated experimentally using batch reactors. The cross-sectional methodology was employed to study possible power generation. Results: The maximum voltage output of 118.93, 144.84, and 89.76 mV were produced keeping the resistance unlimited for MFC1 (urine substrate), MFC2 (blackwater substrate), and MFC3 (graywater substrate), respectively. MFC that utilized graywater as a substrate brought the tiniest quantity of electricity; however, it stood the most stable. The highest COD reduction (65.83%) in the process was reported in urine substrate and the highest BOD5 removal (69.18%) was reported in black water substrate. Conclusion: The experimental results provided a promising indication of MFCs viability, providing hope for future power generation and alternative wastewater treatment option in developing countries.

A comprehensive immunoinformatics study to explore and characterize potential vaccine constructs against Ole e 9 allergen of Olea europaea

Immunoglobulin E (IgE)-mediated allergy, which affects more than 30% of the population, is the most prevalent hypersensitivity illness. In an atopic individual, even a small amount of allergen exposure can cause IgE antibodies to be produced. Due to the engagement of receptors that are highly selective for IgE, even tiny amounts of allergens can induce massive inflammation. This study focuses on the exploration and characterization of the allergen potential of Olea europaea allergen (Ole e 9) affecting the population in Saudi Arabia. A systematic computational approach was performed to identify potential epitopes of allergens and complementary determining regions of IgE. In support, physiochemical characterization and secondary structure analysis unravel the structural conformations of allergens and active sites. Epitope prediction uses a pool of computational algorithms to identify plausible epitopes. Furthermore, the vaccine construct was assessed for its binding efficiency using molecular docking and molecular dynamics simulation studies, which led to strong and stable interactions. This is because IgE is known to play a role in allergic responses, which facilitate host cell activation for an immune response. Overall, the immunoinformatics analysis advocates that the proposed vaccine candidate is safe and immunogenic and therefore can be pushed as a lead for in vitro and in vivo investigations. Communicated by Ramaswamy H. Sarma

Bismuth doped Sr2Fe1.5Mo0.5O6-δ double perovskite as a robust fuel electrode in ceramic oxide cells for direct CO2 electrolysis

Electrochemical conversion of CO2 to CO is an economically feasible method for mitigating greenhouse gas emissions. Among various electrochemical approaches, solid oxide electrolysis cells (SOECs) show high potential for CO2 reduction reaction (CO2-RR) due to their ability to operate at high temperatures, resulting in fast reaction kinetics and increased efficiency. Considering their main energy loss is still associated with the large overpotential at the fuel electrode, the development of the highly efficient and durable cathode for SOECs has been extensively searched after. Here, we propose an A-site doping strategy to enhance the properties of Sr2Fe1.5Mo0.5O6−δ (SFM), which improve its performance as a cathode in SOECs for CO2-RR, demonstrating favorable activity and durability. The structural and physiochemical characterizations, together with DFT calculations, show that the partial replacement of Sr by Bi in the SFM double perovskite not only improves CO2 adsorption capability at the catalyst surface but also enhances oxygen ionic conduction inside the bulk oxide, resulting in enhanced CO2 electrocatalysis performance in SOECs. Specifically, a La0.8Sr0.2Ga0.8Mg0.2O3−δ (LSGM) electrolyte-supported single cell with the new Bi-doped SFM cathode demonstrates a large current density of 1620 mA cm−2 at a cell potential of 1.6 V at 850 °C with good operational stability up to 200 h. Bi-doped SFM thus represents a highly promising cathode for ceramic CO2 electrolyzers and could accelerate our transition towards a carbon-neutral society.

Tyramine modification of high and low methoxyl pectin: Physicochemical properties, antioxidant activity, and gelation behavior

Pectin modification is an effective approach for changing its functional properties and discovering new applications. To provide more insight into the modified pectin structure-function relationships, tyramine (Tyr) modified high (HMP) and low methoxylated pectin (LMP) were prepared to construct novel pectin gel systems. FTIR, 1H NMR, and UV–vis analyses confirmed that Tyr groups were successfully grafted onto pectin chain and obtained the unreacted galacturonic acid (GalA) content. Physiochemical characterization revealed that Tyr modified pectin exhibited enhanced solubility, amphiphilicity and antioxidant activity. Tyr modified pectin gels possessed good viscoelastic property, but obviously decreased elasticity and strength compared to native pectin gel. Entanglement network number (ENN) and scanning electron microscopy (SEM) image demonstrated the decreased internal cross-linking networks density which contributed to the altered gelling properties of Tyr modified pectin gels. The proposed gelling mechanism indicated that bulky Tyr involved physical interactions were mainly responsible for the changed pectin gelling behavior and gelation process in nature. Similarly, the textural properties and water holding capacity (WHC) of Tyr modified pectin gels were closely related to their physical interaction categories and gelling network microstructure. Sucrose induced gellation of the Tyr modified LMP with strong carboxyl groups related hydrogen bonding showed higher hardness. Calcium ions induced gellation of the Tyr modified LMP formed a larger porous gel matrix which resulted in a poor WHC. The findings provide theoretical basis on physicochemical properties and gelling behaviors of Tyr modified pectin for expanding their application in the fields of food preservation, emulsifiers, stabilizers, and tunable gel-type foods.

Novel microemulsions formulated from sodium N-Lauroyl sarcosinate as nanocarrier for encapsulation of α-Tocopherol

Oil-in-water (o/w) microemulsions (MEs) are gaining increasing attention as nanocarriers for the encapsulation and delivery of hydrophobic bioactive molecules which has huge applications in cosmetic, pharmacological, food and beverage industries. However, the major challenge is to formulate these MEs from biodegradable and biocompatible components in low concentration to form stable formulations. In the current work, physiochemical characterization of blank and α-tocopherol loaded o/w MEs formulated using the biodegradable amino-acid based sodium N-lauroyl sarcosinate (SNLS) as surfactant was performed. These MEs were utilized as potential nanocarriers to solubilize and encapsulate an antioxidant α-tocopherol. The utilization of o/w MEs increased the solubility of α-tocopherol from 0.1% in 10% SNLS solution to 0.2% and 0.8% in MEs without and with cosurfactant respectively. The effect of cosurfactant, concentration of Smix (SNLS:butanol = 1:1) and oil was evaluated using conductivity, viscosity studies and encapsulation efficiency to select the optimum composition for encapsulation. The Z-average size of blank MEs without and with cosurfactant was 304 nm and 199 nm respectively with low PDI and negative zeta potential values determine the enhanced stability of these MEs. The HRTEM images revealed the spherical shape of o/w MEs with darker oily core and were utilized to study the effect of cosurfactant and encapsulation of α-tocopherol on the size and morphology of o/w ME droplets. Further, FTIR studies showed the molecular interactions in α-tocopherol and in the optimized ME. In addition to this, the in-vitro antioxidant study of α-tocopherol loaded MEs was determined by the DPPH free radical scavenging activity and the IC50 value was 9 mg/mL for the optimized ME containing 0.5% α-tocopherol. The contact angle studies revealed excellent wetting and spreading ability of MEs on the hydrophobic surface. Thus, SNLS based o/w MEs could be utilized as potential nanocarriers for the encapsulation and delivery of α-tocopherol.

The fermented product of high-yield surfactin strain Bacillus subtilis LYS1 improves the growth performance and intestinal villi morphology in broilers

This study aimed to select Bacillus spp. for surfactin production by solid-state fermentation and to investigate the physiochemical characterizations of the fermented product (FP) and its effect on growth performance, carcass trait, intestinal morphology, and clinical blood biochemistry of broilers. Accordingly, the correlations between the functional components of FP and the growth performance of broilers are elucidated. Four hundred eighty 1-day-old Ross 308 broiler chicks were randomly assigned to dietary supplementation of 2.5% fish meal, 2.5% unfermented product, or 2.5% FP produced by Bacillus subtilis LYS1 (LYS1), Bacillus amyloliquefaciens Da16, B. subtilis Lo6 (Lo6), B. subtilis NSN7, B. subtilis subsp. natto N21, or B. subtilis N12. Each treatment had 6 replicates. The experimental period was 5 wk. Results showed that the Lo6 showed the highest protease activity among all fermented groups. The LYS1 showed the highest surfactin yields (10.69 mg/g) among all fermented groups (P < 0.05). The weight gain (WG), feed conversion ratio (FCR), and production efficiency factor (PEF) of LYS1 group were significantly better than unfermented group at 0 to 3 and 0 to 5-wk-old (P < 0.05). The Bacillus-like counts and surfactin content of FP were moderately correlated to WG (0.7 > r > 0.3), FCR (-0.3 > r > -0.7), and PEF (0.7 > r > 0.3) at 0 to 3 and 0 to 5-wk-old (P < 0.05). The protease activity of FP was moderately correlated to WG (0.7 > r > 0.3), FCR (-0.3 > r > -0.7), and PEF (0.7 > r > 0.3) at 0 to 3-wk-old (P < 0.05). The villus height to crypt depth ratio in duodenum and jejunum of fish meal group and LYS1 group were higher than unfermented group (P < 0.05). In conclusion, LYS1 shows the highest surfactin yields. Diets supplemented with 2.5% LYS1 FP can improve the growth performance and the development of intestinal villi in broilers. Moreover, this study proves that the surfactin content, Bacillus-like counts, and protease activity of FP show a correlation to the growth performance of broilers.

An emergent electrochemical sensor based on spinel zinc manganese oxide decorated on amine-functionalized boron nitride for enhanced electrochemical determination of herbicide mesotrione

Mesotrione (MTO) is a herbicide that is commonly used in agriculture; unfortunately, this chemical often makes its way into aqueous environments. In this study, an MTO sensor was fabricated based on spinel zinc manganese oxide (ZnMn2O4, ZMO) nanoparticles (NPs) and an amine-functionalized boron nitride (NH2-BN) composite. ZMO was synthesized using a coprecipitation technique, and NH2-BN was prepared by a urea-assisted ultrasonication/stirring method. The nanocomposite of ZMO NPs/NH2-BN was prepared using the sonication method. The crystallinity, oxidation states, and functionality of the catalysts were investigated using physiochemical characterization techniques: powder X-ray diffraction analysis, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy. In addition, the surface morphology and topology of the ZMO NPs/NH2-BN composite were analyzed by field-emission scanning electron microscopy and high-resolution transmission electron microscopy. The ZMO NPs/NH2-BN/glassy carbon electrode (GCE) exhibited a well-resolved MTO reduction peak in cyclic voltammetry experiments due to the synergetic effect between the aggregated ZMO NPs and NH2-BN. In addition, ZMO NPs/NH2-BN/GCE exhibited a low limit of detection of 1.5 nM, high sensitivity (1.791 µA µM−1 cm−2), and broad linear ranges (0.01–12.51 µM and 18.51–1777.51 µM). A ZMO NPs/NH2-BN/GCE sensor prototype was used to effectively detect MTO in environmental water samples with good recovery.

Surface, interfacial and thermodynamic aspects of the Rhamnolipid-salt systems

Rhamnolipids have been exploited for fluid–fluid and solid–fluid interactions in various applications due to their excellent surface and interfacial properties. The present work deals with the rhamnolipid-salt system and measured the variation in the thermodynamic and physicochemical properties. A systemic investigation has been carried out; first measured the critical micelle concentration (CMC) of rhamnolipid (200 mg/L) and then the effect of salts over various physiochemical properties of biosurfactant was evaluated. Further, the concentration of rhamnolipid was varied with the selected salts (NaCl, Na2CO3, NaNO3) at optimum concentrations. The physio-chemical characterization of biosurfactant-salt systems was conducted by performing surface tension, particle size/zeta potential, contact angle and microscopic analyses using a tensiometer, dynamic light scattering, goniometer and microscope, respectively. The results demonstrated that the CMC values of rhamnolipid in the biosurfactant-salts system were reduced to 40–60 mg/L. The addition of electrolyte in the rhamnolipid reduced the CMC and surface tension values significantly, which altered the wettability and formed agglomerated structure. The contact angle of rhamnolipid decreased from 76° to 58° in the presence of salt. The reductions in surface tension and CMC value of rhamnolipid have been correlated with the physio-chemical properties of biosurfactant-salt systems. Further, Gibb’s standard free surface energies of rhamnolipid micellization and adsorption at the air–water interface were estimated to predict the thermodynamical behaviour. At CMC values, the surface excess of rhamnolipid was 2.09 × 10−6 mol/m2, which reduced to 1.93 × 10−6 mol/m2 for rhamnolipid-salt systems.

Aniline Formaldehyde Cross-Linked Polyaniline Magnetic Nanocomposite with Core-Shell Structure As A New Platform for Enzyme Immobilization

Objectives: The industrial application of an enzyme is governed by its thermodynamic properties and stability, which can be effectively improved by immobilizing enzymes onto suitable supports. The present work is done by immobilizing a-amylase onto aniline formaldehyde condensate cross-linked polyaniline magnetic nanocomposite. Methods: Physiochemical characterization of synthesized Fe3O4-CLPANI nanocomposite was done by FT-IR, XRD, TG, and SEM images. Biochemical characterization related to immobilization efficiency, the kinetic parameters Vmax and the Km value, thermal stability, storage stability and reusability of immobilized enzymes were determined. Findings: Both physiochemical and biochemical characterization led to the conclusion that Fe3O4–CLPANI immobilized amylase indicated better thermal stability than that of free enzyme and it tailored to the requirement as an industrial catalyst. Novelty: To the best of our knowledge, no literature is available on the immobilization of the enzyme to Fe3O4–CLPANI composites with core-shell structure. Keywords: Nanocomposite; Amylase; Immobilization; Thermal stability; Thermal deactivation a

Development of a Novel Pomegranate Polysaccharide Nanoemulsion Formulation with Anti-Inflammatory, Antioxidant, and Antitumor Properties.

Colorectal cancer is one of the most serious gastrointestinal cancers in Africa and its prevention is a pronounced challenge in contemporary medicine worldwide. The present study aimed to develop nanoemulsion drug delivery system using pomegranate polysaccharides (PGPs) as an alternative cancer remedy, and then the evaluated its biological activities. The PGPs yield and chemical composition were evaluated, and then a PGPs nanoemulsion (PGPs-NE) was prepared using the self-emulsification technique with an oil phase. The physicochemical characterization of PGPs-NE was then analyzed. The in vitro antioxidant, anti-inflammatory activities, and antitumor potency of PGPs and PGPs-NE were also evaluated. The PGPs yield was 10%. The total sugar and protein content of PGPs was 44.66 mg/dl and 19.83μg/ml, respectively. PGPs were mainly composed of five monosaccharides including fructose, glucose, galactose, rhamnose, and arabinose. Concerning physiochemical characterization, the formulated PGPs-NE had three optical absorption bands at 202, 204, and 207nm and a transmittance of 80%. Its average hydrodynamic particle size was 9.5nm, with a PDI of less than 0.2 and a negative zeta potential (-30.6 mV). The spherical shape of PGPs-NE was confirmed by a transmission electron microscope study, with an average size of less than 50 nm. Additionally, the method used to prepare the PGPs-NE formulation provided high entrapment efficiency (92.82%). The current study disclosed that PGPs-NE exhibited strong antioxidant, anti-inflammatory, and antitumor agent potency compared to that of free PGPs. These promising current findings provide evidence for the possible efficacy of novel PGPs-NE as an alternative treatment for CRC.

Gamma alumina coated-PAA/PVP hydrogel as promising quercetin nanocarrier: Physiochemical characterization and toxicity activity

Gamma alumina coated-PAA/PVP hydrogel as promising quercetin nanocarrier: Physiochemical characterization and toxicity activity

Fabrication, bacteriostasis and osteointegration properties researches of the additively-manufactured porous tantalum scaffolds loading vancomycin.

Infected bone defects (IBDs) remains a challenging problem for orthopedists. Clinically, routine management for IBDs has two stages: debridement and systematic antibiotics administration to control infection, and secondary grafting to repair bone defects. Whereas the efficacy is not satisfactory, because the overuse of antibiotics may lead to systemic toxicity, and the emergence of drug-resistant bacteria, as well as the secondary surgery would cause additional trauma and economic burden to the patients. Therefore, it is imperative to develop a novel scaffold for one-stage repair of IBDs. In this study, vancomycin (Van) was encapsulated into poly(lactic co-glycolic acid) (PLGA) microspheres through the double emulsion method, which were then loaded into the additively-manufactured porous tantalum (AM-Ta) through gelatin methacryloyl (GelMA) hydrogel to produce the composite Ta/GelMA hydrogel (Gel)/PLGA/vancomycin(Van) scaffolds for repairing IBDs. Physiochemical characterization of the newly-developed scaffold indicated that the releasing duration of Van was over 2 weeks. Biological experiments indicated good biocompatibility of the composite scaffold, as well as bacteriostasis and osteointegration properties, which showed great potential for clinical application. The construction of this novel scaffold would provide new sight into the development of orthopaedic implants, shedding a novel light on the treatment of IBDs.

Production and Physiochemical Characterization of Biodiesel from Nile cabbage grown in Pager River, Kitgum Municipality, Northern-Uganda

Nile cabbage (Pistia stratiotes) represents a promising source of biodiesel which has been garnered due to good biomass yield. This study aims to determine the possibility for biodiesel production from Nile cabbage plants collected from a seasonal Pager River. The bio-oil extraction from Nile cabbage leaves was done using soxhlet apparatus. The biodiesel was produced by transesterification of lipids and characterized by GC-FID and the physio-chemical parameters of the produced biodiesel were also performed. The obtained results indicate that, Nile cabbage sample showed a yield of biodiesel (30.30±0.01) %. The biodiesel obtained possess the following fuel properties: density (880.00±0.00)Kg/m3, pH (5.70±0.00), saponification value (137.10±0.09) mg KOH/g, acid value (1.00±0.00) mg KOH/g, iodine value (63.41±0.01) mg I2/100g, flash point (120±0.00)℃, pour point (-6.20±0.03) ℃, colour (brown), moisture content (50.00±0.00)%, and ash content (0.003±0.00)%, and cetane number (49.53±0.05). The GC-FID analysis of the obtained biodiesel showed the presence of C16:0, C18:0, C18:1 and C18:2 as the major constituents of fatty acids (FAs) detected. Therefore, all physiochemical parameters were within the allowable limits, accept only acid value which was slightly higher than the standard limits issued by the American and European (ASTM D 6571:12 and EN 14214:2012) standards. Aquatic weeds are considered a global threat in the aquatic ecosystem, which invoked a lot of attention from the general public and the scientific community. Our findings showed that Nile cabbage biomass could give a significant yield of biodiesel, with desired fuel properties which will initiates a cleaner energy.

GL67 lipid-based liposomal formulation for efficient siRNA delivery into human lung cancer cells

The efficient delivery of small interfering RNA (siRNA) to the targeted cells significantly affects the regulation of the overexpressed proteins involved in the progression of several genetic diseases. SiRNA molecules in naked form suffer from low internalization across the cell membrane, high susceptibility to degradation by nuclease enzyme and low stability, which hinder their efficacy. Therefore, there is an urge to develop a delivery system that can protect siRNA from degradation and facilitate their uptake across the cell membrane. In this study, the cationic lipid (GL67) was exploited, in addition to DC-Chol and DOPE lipids, to design an efficient liposomal nanocarrier for siRNA delivery. The physiochemical characterizations demonstrated that the molar ratio of 3:1 has proper particle size measurements from 144 nm to 332 nm and zeta potential of −9 mV to 47 mV that depends on the ratio of the GL67 in the liposomal formulation. Gel retardation assay exhibited that increasing the percentage of GL67 in the formulations has a good impact on the encapsulation efficiency compared to DC-Chol. The optimal formulations of the 3:1 M ratio also showed high metabolic activity against A549 cells following a 24 h cell exposure. Flow cytometry findings showed that the highest GL67 lipid ratio (100 % GL67 and 0 % DC-Chol) had the highest percentage of cellular uptake. The lipoplex nanocarriers based on GL67 lipid could potentially influence treating genetic diseases owing to the high internalization efficiency and safety profile.

Tin Oxide-Graphene Oxide (SnO2/GO) Nanocomposite: A Promising Photocatalyst for Rhodamine-B Dye Degradation

Appropriate wastewater treatment methods for effectual and practical decontamination of wastewater bodies is the prime goal of today’s environmentalists and industrialists. Herein, sunlight driven photocatalytic degradation of rhodamine-B (RhB) has been investigated by employing hydrothermally synthesized tin oxide-graphene oxide (SnO2/GO) nanocomposite. Physiochemical characterization of composite has been accomplished via X-ray diffraction (XRD) analysis, ultraviolet (UV) spectroscopy, diffused reflectance spectroscopy (DRS) and photoluminescence (PL). Photocatalytic degradation of RhB is studied using UV light and spectrophotometer. SnO2-GO nanocomposite degraded the RhB dye in 120 min comparatively in quite lesser time than separate SnO2 and GO degradation performances. The incorporation of GO into SnO2 decreases the rate of electron–hole recombination, increases the oxidation of carriers as well as the rate of carrier separation owing to the synergistic impact of GO and SnO2. Therefore, an affordable graphene oxide supported SnO2 nanocomposite can be implicated as efficacious real wastewater treatment method at industrial scale.

Soil microbiome dynamics associated with conversion of tropical forests to different rubber based land use management systems

The biogeochemical cycles, carbon sequestration, and climate change all are significantly influenced by tropical rainforests, which is one of the world's most productive ecosystems and hotspots for biodiversity. Plantation crops like Rubber (Hevea brasiliensis) have displaced significant forest cover in the Asia pacific in the last two centuries due to their increasing demand. As a case study, we examined the soils of native forest (NF), rubber monoculture (RP) and three different managements i.e., cover crop (CC), weed crop (WC) and inter crop (IC) to understand the changes in microbial community structure across each practice and to estimate the influence of forest conversion to rubber monoculture on the soil microbiome. Soils were collected using nested sampling pattern and subjected to physiochemical characterization and whole metagenome sequencing. Results revealed that bacteria (60.56 M reads) predominated all land use types, followed by eukaryotes (0.52 M reads) and archaea (0.72 M reads). NF exhibited significantly higher bacterial richness and diversity then other land-use type. Interestingly, total functional diversity as well as genes associated with chemotaxis, flagellar assembly, and secretion systems were significantly higher in other land-use systems as compared to NF. Altogether, the results from this study indicate that the three different land use types used here like CC, IC, and WC has high abundance of functional diversity and biological profile compared to NF and RP. The study suggests that the adoption of aforementioned land-use management practices could play a significant role in fostering sustainable plantations in the tropics.

Visible light driven Ni doped hematite for photocatalytic reduction of noxious methylene blue

In recent studies, pure Fe2O3 (FO) and a series of 5% Ni doped Fe2O3 (5-NFO), 10% Ni doped Fe2O3 (10-NFO), and 15% Ni doped Fe2O3 (15-NFO) nanoparticles were simply synthesized by employing the eco-friendly hydrothermal approach to assess the effect of doping concentration on photocatalytic activity. Different instrumental techniques were used to examine FO, 5-NFO, 10-NFO and 15-NFO nanoparticles to determine the structural and functional features of the materials. Incorporation of Ni2+ ions into Fe2O3 was confirmed by these physiochemical characterization techniques. The crystallite size of synthetic materials was investigated using the Scherrer expression. The average particle size reduced from 46 nm in undoped samples to 19 nm in doped ones. Scanning electron microscopy (SEM) analysis revealed that adding of Ni dopant to Fe2O3 nanoparticles reduced particle aggregation and increased surface area. Optical properties of synthesized nanoparticles such as FO, 5-NFO, 10-NFO, and 15-NFO have bandgap energies of 2.25, 1.83, 1.71, and 1.47 eV, respectively, as determined by UV–visible spectroscopic analysis. The usual photocatalytic behavior of doped hematite is owing to the reduction of its bandgap energy. The highest methylene blue degradation was achieved by using 10-NFO after 100 min. The optimal concentration of 10-NFO accelerates the photoreduction of methylene blue (MB) because of the photocatalyst's potent ability to trap electrons.

Unexpected Negative Performance of PdRhNi Electrocatalysts toward Ethanol Oxidation Reaction.

Direct ethanol fuel cells (DEFCs) need newly designed novel affordable catalysts for commercialization. Additionally, unlike bimetallic systems, trimetallic catalytic systems are not extensively investigated in terms of their catalytic potential toward redox reactions in fuel cells. Furthermore, the Rh potential to break the ethanol rigid C-C bond at low applied potentials, and therefore enhance the DEFC efficiency and CO2 yield, is controversial amongst researchers. In this work, two PdRhNi/C, Pd/C, Rh/C and Ni/C electrocatalysts are synthesized via a one-step impregnation process at ambient pressure and temperature. The catalysts are then applied for ethanol electrooxidation reaction (EOR). Electrochemical evaluation is performed using cyclic voltammetry (CV) and chronoamperometry (CA). Physiochemical characterization is pursued using X-ray diffraction (XRD), transmission electron microscope (TEM), energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). Unlike Pd/C, the prepared Rh/C and Ni/C do not show any activity for (EOR). The followed protocol produces alloyed dispersed PdRhNi nanoparticles of 3 nm in size. However, the PdRhNi/C samples underperform the monometallic Pd/C, even though the Ni or Rh individual addition to it enhances its activity, as reported in the literature herein. The exact reasons for the low PdRhNi performance are not fully understood. However, a reasonable reference can be given about the lower Pd surface coverage on both PdRhNi samples according to the XPS and EDX results. Furthermore, adding both Rh and Ni to Pd exercises compressive strain on the Pd lattice, noted by the PdRhNi XRD peak shift to higher angles.

Development of Value-Added Butter by Incorporating Whey Protein Hydrolysate-Encapsulated Probiotics.

The probiotic foods market is growing exponentially; however, probiotics' survivability and interaction with product attributes pose major challenges. A previous study of our lab developed a spray-dried encapsulant utilizing whey protein hydrolysate-maltodextrin and probiotics with high viable counts and enhanced bioactive properties. Viscous products such as butter could be suitable carriers for such encapsulated probiotics. The objective of the current study was to standardize this encapsulant in salted and unsalted butter, followed by storage stability studies at 4 °C. Butter was prepared at a lab-scale level, and the encapsulant was added at 0.1% and 1%, followed by physiochemical and microbiological characterization. Analyses were conducted in triplicates, and means were differentiated (p < 0.05). The viability of probiotic bacteria and the physicochemical characteristics of the butter samples with 1% encapsulant were significantly higher as compared to 0.1%. Furthermore, the 1% encapsulated probiotics butter variant showed a relatively higher stability of probiotics ratio (LA5 and BB12) than the control with unencapsulated probiotics during storage conditions. Although the acid values increased along with a mixed trend of hardness, the difference was insignificant. This study thus provided a proof of concept for incorporating encapsulated probiotics in salted and unsalted butter samples.

Poultry litter physiochemical characterization based on production conditions for circular systems

Poultry litter is a useful product as a fertilizer, energy feedstock for thermochemical conversion, and a precursor for synthesis of adsorbents and catalysts. Detailed characterization of baseline properties is necessary for enhanced environmental and economic utilization of this valuable resource. Baseline physicochemical characterization was carried out at two broiler production facilities (Arkansas, PL1, and North Carolina, PL2). Greater concentrations of inorganic nitrogen, phosphorus, and potassium were obtained for PL1, suggesting greater nutrient value compared to PL2. PL2 had greater carbon content and water-holding capacity than PL1. X-ray photoelectron spectroscopy (XPS) of PL1 and PL2 indicated a similarity between litters in terms of the presence of carbon, nitrogen, and oxygen bonds. Both poultry litters had oxygen, nitrogen, sulfur, and phosphorous functional groups, as confirmed by infrared spectroscopy. Time of flight – secondary ion mass spectroscopy of negative ions also indicated similarity of the surface charge distribution between PL1 and PL2. Overall, poultry litters evaluated had similar surface chemistries, with nutrient composition varying based on rearing conditions, which has implications for downstream use in thermochemical conversion and other value-added products.