Final pH Research Articles

A novel static cultivation of bacterial cellulose production from sugar beet molasses: Series static culture (SSC) system

In bacterial cellulose (BC) production, we developed a new static cultivation system named series static culture (SSC) to eliminate air limitation problem encountered in conventional static culture (CSC). In SSC system, the fermentation broth at the bottom of BC pellicle produced in initial culture medium is transferred to the next empty sterile culture medium at the end of a certain fermentation period. This procedure was performed until BC production ceased. Fermentation experiments were carried out using Gluconacetobacter xylinus NRRL B-759 and sugar beet molasses at 30 °C and initial pH 5. Also, some quality parameters of produced BC pellicles were determined. Final pH at the stages of SSC system was higher that of the initial pH due to sugar content (sucrose) of molasses and microorganism used. Total BC production increased with increasing sugar concentration in SSC. As a result, an increase of 22.02 % in BC production was achieved using developed SSC. FT-IR spectra of all BC pellicles produced were typical spectra. The absorption bands at the relevant wavenumbers identify the mode of vibrations of the created chemical bonds arising at the BC surface such as OH, CH, H-O-H, C-O-C, and C-OH. XRD analyses showed that the crystallinity index values of BC obtained from CCS and SSC were high. The form of produced all BC pellicles is generally Cellulose I. Removal of surface moisture and depolymerisation of carbon skeleton were determined from TGA-DTA thermograms. SEM images showed that the BC samples produced had nano-sized cellulose fibrils which were aggregated in fermentation media containing molasses. Finally, the BC samples, especially in molasses media, having high mechanical strength and WHC were found.

Non-Dairy Fermented Beverages Produced with Functional Lactic Acid Bacteria.

At present, there is an increasing interest in beverages of non-dairy origin, as alternatives to those based on milk, but having similar health-promoting properties. Fermentation with specific bacteria or consortia may enhance the functionality of these products. In our study, selected lactic acid bacteria, that have been previously shown to possess functional properties (antimicrobial activity, probiotic potential), were used for the fermentation of wheat bran combined with root vegetables. Strains were investigated for their safety, while the obtained beverages were characterized in terms of microbial content, physical, chemical, nutritional, and functional properties. None of the strains harbors virulence genes, but all of them possess genes for survival at low pH, starch metabolism, and vitamin biosynthesis. Three strains (Lactiplantibacillus plantarum BR9, L. plantarum P35, and Lactobacillus acidophilus IBB801) and two substrates (5% wheat bran with 10% red beetroot/carrots) were selected based on a preliminary assessment of the beverage's sensory acceptability. These strains showed good growth and stability over time in the stored beverages. No enterobacteria were detected at the end of fermentations, while the final pH was, in most cases, below 3.5. Free phenolics, flavonoids, and DPPH scavenging effect increased during fermentation in all drinks, reaching 24h values that were much higher than in the unfermented substrates. Most of the obtained drinks were able to prevent the growth of certain pathogens, including Listeria monocytogenes ATCC 19111, Salmonella enterica ATCC 14028, Staphylococcus aureus ATCC 25923, and Escherichia coli ATCC 25922. The obtained beverages would combine the nutritiveness of the raw ingredients with the beneficial effect of fermentation (increasing shelf life, health-promoting effect, pleasant flavor, etc.). They would also fill a gap in the non-dairy probiotics sector, which is constantly increasing due to the increasing number of vegan people or people that cannot consume dairy products.

Optimization of Culture Conditions and Wheat Bran Class Selection in the Production of Bacillus thuringiensis-Based Biopesticides

Bacillus thuringiensis is the leading microbial-based biopesticide, thanks to its parasporal crystal proteins or δ-endotoxins, which are toxic to insect larvae upon ingestion. Once in the insect larvae midgut, the crystal is solubilized by the alkaline pH and the δ-endotoxins activated by proteolytic cleavage. Thanks to its high efficiency as a biopesticide, several efforts have been made to enhance its growth and δ-endotoxins production, in various types of culture media. In this study, a culture medium based on wheat bran (WB), the by-product of cereal grain milling, was used to grow Bacillus thuringiensis and produce δ-endotoxins. Using the response surface methodology (RSM), the effects of three variables were evaluated: WB particles granulometry, their concentration, and their agitation in a 48-h shake-flask culture at 30 °C. Three response parameters were targeted: δ-endotoxins production, final culture pH, and dry-matter consumption. According to the RSM results, the optimum would be at 3.7 g WB/50 mL, with a granulometry above 680 μm and agitation between 170 and 270 rpm. This study is key to developing natural and cheap culture media that can be used at an industrial level for Bacillus thuringiensis-based biopesticides.

Iron-calcium reinforced solidification of arsenic alkali residue in geopolymer composite: Wide pH stabilization and its mechanism

Arsenic-alkali residue (AAR) from antimony production can pose significant health and environmental hazards due to the risk of arsenic (As) leaching. In this study, geopolymer composite synthesized from fly ash (FA) was investigated for efficient stabilization of high-arsenic-containing AAR (As2O3 of 22.74 wt%). Two industrial wastes, e.g., granulated blast furnace slag (GBFS) with active calcium composition and water-quenched slag (WQS) from lead-zinc smelting with active iron composition, were investigated for the reinforcement of AAR geopolymer solidification. A wide pH stabilization (from pH = 3–pH = 12) of AAR with the geopolymer composite was successfully achieved, and As leaching concentration of geopolymer with the addition of 5 wt% AAR was significantly reduced from 2343.73 mg/L (AAR) to that below 0.18 mg/L, which successfully meet the regulatory limit of Chinese domestic waste landfill (GB, 18598−2019, 1.2 mg/L) and hazardous waste landfill (GB16889-2008, 0.3 mg/L). Johnbaumite (Ca5(AsO4)3(OH)) was formed in geopolymer composite and leached samples with initial pH from 2.6 to 6 (final pH from 5.54 to 13.15). Magnetite and iron hydroxide phases with strong adsorption and/or As co-precipitation capability were also observed. As stabilization was also achieved with iron oxidation from As(III) to As(V). This study solves the problem of unstable As leaching at different pH for the solidification of arsenic-bearing solid waste, and provides a promising and practical strategy for efficient solidification/stabilization of AAR as well as other similar arsenic-bearing solid wastes with geopolymer composite.

Effects of Lactic Acid Bacteria Inoculants and Stage-Increased Storage Temperature on Silage Fermentation of Oat on the Qinghai–Tibet Plateau

Ensiling is a simple and effective method of alleviating a shortage of forage for ruminants. This study aimed to investigate the effects of lactic acid bacteria (LAB) inoculants and stage-increased temperature on the fermentation characteristics and chemical composition of oat silage on the Qinghai–Tibet Plateau. The silage was treated with local laboratory inoculant (I) and commercial inoculant (S) and stored at ambient temperature (<10 °C) or stage-increased (5, 10 and 15 days) temperatures of 10 °C and 15 °C for 60 days. The results showed that stage-increased storage temperature can improve silage fermentation. Compared with 10 °C, a stage-increased storage temperature of 15 °C effectively (p < 0.05) promoted the fermentation rate of silage by increasing the dominance of Lactiplantibacillus plantarum, with higher lactic, acetic and propionic acid contents and a lower ammonia-N ratio of the total N and final pH value. Compared with S, treatment with I increased the water-soluble carbohydrate and lactic acid contents and decreased the ammonia-N ratio of the total N and final pH value. This work demonstrated that increasing the storage temperature in stages using a warming infrastructure facilitates the preservation of oat silage in cold regions, and the inoculation of lactic acid bacteria could advance silage fermentation on the Qinghai–Tibet Plateau.

Catalytic performances and leaching behavior of typical natural iron minerals as electro-Fenton catalysts for mineralization of imidacloprid

Catalytic performances and leaching behavior of 9 natural iron minerals as heterogeneous electro-Fenton catalysts for the treatment of imidacloprid wastewater were studied. The results showed that magnesioferrite exhibited the best catalytic ability among these minerals with UV absorbance at 270 nm (UV270) removal of 83.59% and COD removal of 49.11% within 4 h using graphite cathode and Ti/(RuO2)0.88-(IrO2)0.12 anode at initial pH 3 with a catalyst dose of 5 g/L, a current density of 40 mA/cm2 and an electrode spacing of 2 cm. The instantaneous current efficiency (ICE) at 4 h and energy consumption (EC) reached 2.30% and 2.20 kWh/gCOD respectively. It was found that the components contained in natural iron minerals, such as Al, alkali metal (K) and alkaline earth metals (Mg, Ca, Ba), would dissolve into the electrolyte solution, raising the final pH to 6.5–8.5 and ultimately reducing the reaction efficiency. Except magnetite and magnesioferrite, other minerals, such as ilmenite and V-Ti magnetite, were likely to cause secondary pollution. The subsequent adjustment to alkaline state for chemical precipitation of leached Mn was needed. Pyrite showed relatively high leachability in hazardous elements (especially Pb), which should be carefully evaluated before its actual application in electro-Fenton process.

Degradation of phenol by ball-milled activated carbon (ACBM) activated dual oxidant (persulfate/calcium peroxide) system: Effect of preadsorption and sequential injection

This study explored pre-adsorption and sequential injection of dual oxidant (DuOx) of persulfate (PS) and calcium peroxide (CP) for phenol degradation in an aqueous solution. Ball-milled activated carbon (ACBM) was used as the catalyst in the following systems: pre-adsorption and sequential injection of PS and CP (ACBM + PS + CP), pre-adsorption and simultaneous injection of PS and CP (ACBM + PS/CP), simultaneous injection of ACBM, PS, and CP (ACBM/PS/CP), simultaneous injection of ACBM and PS (ACBM/PS), and simultaneous injection of ACBM and CP (ACBM/CP). The ACBM had a larger specific surface area, more graphitic structures, and more defects. Moreover, it showed better phenol removal when introduced simultaneously with PS and CP. The phenol removal was most the efficient in ACBM + PS + CP (98.8%) with a near-neutral final pH, followed by ACBM + PS/CP, ACBM/PS, ACBM/PS/CP, and ACBM/CP. This indicates that pre-adsorption and separate injection of PS and CP were the key strategy for improved performance and maintained favorable pH for the activation of PS and CP. The dual oxidant system (PS/CP) is superior to single oxidant systems (PS or CP). Scavenger experiments and the electron spin resonance spectra (ESR) demonstrated that non-radical species (1O2) were dominantly involved in ACBM + PS + CP, but radical species (HO•, SO4•−) also contributed. HCO3− and HPO42− inhibited phenol degradation in ACBM + PS + CP, whereas Cl− and HA had negligible effects. The ACBM + PS + CP showed high total organic carbon removal and ACBM was recyclable with a slight decrease in activity. This work is important as it provides a detailed insight into the strategy of pre-adsorption and sequential injection of dual oxidants for a practical and cost-effective method of groundwater remediation.

Evaluation of physico chemical properties, cell viability and mineralization potential of New Pozzolan (fly Ash)-Based Mineral Trioxide Aggregate cement.

To evaluate the effect of New Pozzolan(Fly Ash) on physicomechanical properties, cell viability of human pulpal cells (DPSCs) and mineralization potential when incorporated in various concentration in MTA. Groups were based on addition or absence of fly ash; FM (Fly ash modified MTA) and CM (Conventional MTA) respectively. The initial and final setting time, compressive strength and pH was evaluated using Gillmore needle, ISO 4012:1978 and pH meter at varying time intervals. The cell viability and mineralization potential was analyzed using MTT assay and ALP activity respectively at varying time intervals. Data was analyzed using Kruskall Wallis test followed by Dunn's Post Hoc test (p<0.05). 0.5 FM showed lower final setting time (p<0.05) compared to all the other groups. Significantly increased compressive strength was noted in all FM groups at 24h compared to CM; but no significant difference at day 21. No significant difference was observed in pH at varying time intervals. At day 7, 0.5 FM had significantly higher cell viability compared to all the other groups, but no difference was noted at day 14 (p>0.05). Significantly increased ALP activity in 0.5 FM compared to other groups (p<0.05). An admixture of 0.5% fly ash incorporated MTA when compared with unmodified MTA, significantly increased cell viability and ALP activity (mineralization potential) with lesser setting time. Significant increase in compressive strength was obtained in all fly ash modified MTA with no variation in pH at different time intervals.

Degradation of COD in antibiotic wastewater by a combination process of electrochemistry, hydroxyl-functionalized ball-milled zero-valent iron/Fe3O4 and Oxone

ABSTRACT In this study, the significant iron-based material, hydroxyl-functionalized ball-milled zero-valent iron/Fe3O4 (HFB-ZVI/Fe3O4) was employed for the experiments. The performance of the Electro + HFB-ZVI/Fe3O4 + Oxone system for the degradation of chemical oxygen demand (COD) in antibiotic wastewater was investigated. A direct current was applied between a graphite plate anode and two iron plate cathodes, and a series of operational parameters, such as applied electric current, the dosage of HFB-ZVI/Fe3O4 composite, the dosage of Oxone, and initial solution pH, were explored to evaluate the oxidation process. The application of electric current enhanced the gradual degradation of COD and the increase of current intensity accelerated COD degradation. The neutral condition was favourable for the rapid degradation of COD in a short reaction time by the Electro + HFB-ZVI/Fe3O4 + Oxone process and promoted the degradation efficiency of COD. An increase of electric current gradually decreased the reaction solution pH, the larger the electric current applied in the reaction process, the lower the final pH of the reaction solution. Under the optimal experimental conditions (1 g/L HFB-ZVI/Fe3O4 composite, 0.3 g/L Oxone, current intensity = 500 mA, initial solution pH = 7.85), Electro + HFB-ZVI/Fe3O4 + Oxone achieved 99% COD degradation in antibiotic wastewater. Radicals quenching experiments indicated the contribution to COD degradation by hydroxyl radicals (HO•), sulphate radicals (SO4 •–) and other oxidants were 66.03%, 24.014% and 9.756%, respectively. The possible mechanism of COD degradation in the Electro + HFB-ZVI/Fe3O4 + Oxone system was also discussed in this study. The findings in this work provided useful information for the treatment of wastewater.

Carcass traits and meat characteristics of grazing Nellore cattle submitted to different supplementation strategies in the tropics.

This study explored the effects of different supplementation strategies during the dry and rainy seasons in the tropics on the carcass traits and meat quality of Nellore cattle produced under grazing conditions. Additionally, a cost assessment of the supplementation strategies was conducted to define the most suitable ones from an economic standpoint. Twenty-eight non-castrated male animals (18months) with an initial body weight of 327.9 ± 4.2kg were used. The animals were equitably distributed in a randomized complete design thorough four supplementation strategies as follows: (i) mineral supplementation (MS) in both dry and rainy seasons (MS/MS), (ii) MS during the dry season and concentrate supplementation (CS) during the rainy season (MS/CS), (iii) CS during the dry season and MS during the rainy season (CS/MS), and (iv) CS in both dry and rainy seasons (CS/CS). Thereafter, carcass traits, primary carcass cut yields, meat quality traits, and chemical composition of the meat of cattle produced across different supplementation strategies were determined. Data revealed that animals under CS/CS showed the greatest (P < 0.01) hot carcass weights among the other supplementation strategies evaluated. Conversely, supplementation strategy did not affect (P > 0.10) the carcass traits (the ribeye area, final pH, and forequarter), meat quality traits (shear force, myofibrillar fragment index, sarcomere length, and color), and meat chemical composition (crude protein, fat, and moisture) of the animals. A cost assessment of the supplementation strategies revealed that CS/CS had the highest production costs. Nevertheless, CS/CS had the greatest income and profit, while MS/MS had the lowest ones. In conclusion, data suggest that cattle grazing on tropical forage under CS during at least one season (i.e., dry or rainy) produce similar meat quality traits and chemical composition of meat to those observed for animals under CS in both seasons. Additionally, the last supplementation strategy revealed the greatest profit indicators among the other explored.

Optimization and Kinetic Study of the Electrochemical-Assisted Leaching of Valuable Metals in Lithium-Ion Batteries

Efficient recycling of lithium-ion batteries (LIB) is required to meeting future demand of materials and support sustainable decarbonized energy systems. At the center of the recycling process is the recovery of valuable active metals in LIBs. Hydrometallurgical recovery processes are considered cleaner and less expensive than pyrometallurgical processes, and we previously reported a hydrometallurgical process for the leaching of valuable metals in mixed shredded LIBs. [1] In this process the reductant Fe2+, at low concentration, is electrochemically regenerated to complete the leaching of metals of interest Co, Ni, Li, Mn, and removal of Cu from LIB black mass, eliminating the need of H2O2. To accelerate this process and reduce chemical and energy consumption, the effect of process variables needs to be better understood. In this work, we study the effect of added electrochemical mediator concentration (Fe), total current and agitation level on the kinetics and leaching efficiency the EC-leaching process. Moreover, we propose a new multi-stage leaching scheme for the adjustment of final pH and recirculation of iron in the system.

Nutritive value, silage fermentation characteristics, and aerobic stability of grass-legume round-baled silages at differing moisture concentrations with and without manure fertilization and microbial inoculation.

For baled silages, production of clostridial fermentation products can be exacerbated by exceeding normal moisture targets (45% to 55%), and/or by the application of dairy slurry before harvest. Our objectives were to test a microbial inoculant as a mitigant of clostridial products in high-moisture, grass-legume (52% ± 13.8% cool-season grasses, 44.0% ± 14.0% legumes [predominately alfalfa]) baled silages in swards that were fertilized with dairy slurry. A secondary objective was to examine the effects of bale moisture and inoculation on the aerobic stability of these fermented silages following exposure to air. After the first-cutting was removed, three manure treatments were applied as a whole-plot factor: 1) control (no manure); 2) slurry applied immediately to stubble (63,250 L/ha); or 3) slurry applied after a 1-wk delay (57,484 L/ha). An interactive arrangement of bale moisture (64.1% or 48.4%) and inoculation (yes or no) served as a subplot term in the experiment. The inoculant contained both homolactic (Lactococcus lactis 0224) and heterolactic (Lactobacillus buchneri LB1819) bacteria. The experimental design was analyzed as a randomized complete block with four replications, and the study included 48 experimental units (1.2 × 1.2-m round bales). Total fermentation acids were affected (P ≤ 0.021) by slurry application strategies, but this was likely related to inconsistent bale moisture across slurry-application treatments. Concentrations of butyric acid were low, and there were no detectable contrasts comparing manure treatments (mean = 0.05%; P ≥ 0.645). Bale moisture affected all measures of fermentation, with bales made at 64.1% moisture exhibiting a more acidic final pH (4.39 vs. 4.63; P < 0.001), less residual water-soluble carbohydrates (2.1% vs. 5.1%; P < 0.001), as well as greater lactic acid (4.64% vs. 2.46%; P < 0.001), acetic acid (2.26% vs. 1.32%; P < 0.001), and total fermentation acids (7.37% vs. 3.97%; P < 0.001). Inoculation also reduced pH (4.47 vs. 4.56; P = 0.029), and increased acetic acid (1.97% vs. 1.61%; P < 0.001) and 1,2-propanediol (1.09% vs. 0.72%; P < 0.001) compared to controls. During a 34-d aerobic exposure period, maximum surface bale temperatures were not affected (P ≥ 0.186) by any aspect of treatment, likely due to the prevailing cool ambient temperatures; however, yeast counts were numerically lower in response to greater (P < 0.001) production of acetic acid that was stimulated by both high bale moisture and inoculation.

Cold-set oat protein isolate--gellan gum binary gels with various microstructures: Fabrication, characterization, formation mechanism, and controlled release properties

Cold-set oat protein isolate (OPI) and gellan gum (GG) binary gels with various microstructures was fabricated with different amounts glucono-δ-lactone (GDL) as a carrier to deliver bioactive compounds. OPI and GG formed gel-like mixture at pH 8 mainly via hydrophobic interactions with a binding constant (Ka) of 3.85 × 104 M−1, while the mixture showed highest storage modulus (G′) with 0.1% GG (w/w, based on the dry weight of protein). Novel binary gels fabricated with 7% OPI (w/v) and 0.1% GG (w/w) (OGG) were then developed through addition of various amounts of GDL. For the gels prepared with 1.5% and 4.0% GDL (w/w, based on the dry weight of protein, pH 7.1 and 6.3, respectively), heterogeneous network formed by co-aggregated OPI and GG with a small amount of small GG particles dispersed within large aqueous pores were fabricated mainly through hydrophobic interactions. For OGG-3 (9.0% GDL, w/w) and OGG-4 (20.0% GDL, w/w), the final pH was 5.1 and 4.1 that around or lower than OPI's isoelectric point, hydrogen bonding and electrostatic attractive forces were developed between two polymers since OPI contained neat or positive charges, resulting in a compact coupled OPI-GG network structure. Heterogeneous network with small GG particles dispersed in pores allowed OGG-2 (4.0% GDL, w/w) had comparable good gel hardness to the gel formed with 9.0% GDL (w/w, OGG-3) with coupled microstructure, whereas OGG-3 showed a better ability to restrict the swelling induced release of riboflavin in SGF, and allowed sustainable release of riboflavin in SIF. Therefore, OPI-GG binary gels with various microstructures prepared by simple acidification method at ambient temperature have great potential to be used as delivery systems for heat-sensitive bioactive compounds in food and non-food applications.

RESEARCH ON THE INFLUENCE OF DIFFERENT TYPES OF ANION-EXCHANGE CARTRIDGES ON THE QUALITY OF [18F]NAF RADIOPHARMACEUTICAL AS PART OF PRODUCTION PROCESS DEVELOPMENT

[18F]Sodium Fluoride radiopharmaceutical is a sterile solution for intravenous administration, intendedfor skeletal visualization by positron emission tomography (PET). [18F]Sodium Fluoride for bone imaging wasintroduced in early 1960's, but with the increased availability of PET scanners in the last two decades, thisradiopharmaceutical has growing use in clinical practice for the detection of bone metastases. The productionprocess of [18F]NaF includes production of the radioisotope [18F]F- and purification and formulation of the [18F]NaFradiopharmaceutical. The radioisotope [18F]F- is produced by a cyclotron via the 18O(p,n)18F nuclear reaction,followed by recovery of [18F]F- from [18O] proton-irradiated water by adsorption and desorption from anionexchangeresins. The fluoride anions are trapped on the anion-exchange SPE (solid-phase extraction) cartridge, andall other cationic and water-soluble radionuclide impurities present in irradiated enriched water are collected in thewaste vial. Next step is desorption of the fluoride anions from the cartridge by elution with saline solution (0.9%NaCl). This study aimed to define the most appropriate type of anion-exchange SPE cartridge which could be usedfor routine production [18F]Sodium fluoride radiopharmaceutical which meets the quality requirements defined inEuropean pharmacopeia monograph. For that purpose, as part of development of in-house production method,manual productions with four different types of anion-exchange cartridges were performed. The influence of sorbentsubstrate and counter-ion of the cartridge on the final yield and the quality of the produced radiopharmaceutical wasinvestigated. The study also aimed to define the minimum volume of physiological solution required for the pHparameter to be within limits.The results have shown that the quality parameters: appearance, chemical purity, radiochemical purity andradionuclide purity were in defined acceptance criteria and did not differ when using different anion-exchangecartridges. The pH analyses have demonstrated that the type of cartridge and counter-ion influence the final pH of[18F]NaF solution. This study confirmed that the three types of anion-exchange resins (QMA-Cl-, QMA-CO32- andPS-OH-) could be used for production. In the experiments where QMA-Cl- was used, the required pH level wasobtained even without dilution. The other cartridges could be used in the [18F]NaF production process, but furtherdilution is necessary in order to obtain the pH value in acceptance criteria. On the basis of this study, the QMA-Cl- ischosen as a cartridge to be used in the further development of the in-house method for [18F]NaF radiopharmaceuticalproduction.

Catalytic Dye Oxidation over CeO2 Nanoparticles Supported on Regenerated Cellulose Membrane

A novel regenerated cellulose (RC) membrane containing cerium oxide (CeO2) nanoparticles is described in detail. In this work, CeO2 nanoparticles with high surface area and mesoporosity were prepared by a modified template-assisted precipitation method. Successful synthesis was achieved using cerium nitrate as a precursor, adjusting the final pH solution to around 11 by ammonium hydroxide and ethylene diamine, and annealing at 550 °C for 3 hours under a protective gas flow. This resulted in a surface area of 55.55 m².g–1 for the nanoparticles. The regenerated cellulose membrane containing CeO2 particles was synthesized by the novel and environmentally friendly method. The catalyst CeO2 and cellulose/CeO2 membrane were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Electron paramagnetic resonance (EPR), and Brunauer-Emmett-Teller (BET) measurements. The g-value of 2.276 has confirmed the presence of the surface superoxide species of CeO2 nanoparticles in EPR. The photocatalytic activity of the catalyst and the membrane containing the catalyst was evaluated through the degradation of methylene blue under visible light irradiation by UV-VIS measurements. The cellulose/CeO2 membrane degraded 80% of the methylene blue solution in 120 minutes, showing a better photocatalytic activity than the CeO2 catalyst, which degraded approximately 62% in the same period. It has been proven that the RC membrane is not only a good transparent supporting material but also a good adsorption for high-performance of CeO2 catalyst. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Quality study of PDO (Protected Designation of Origin) Greek white wines of the grape variety ‘Debina’

In this study ‘Debina’ (Zitsa, Ioannina, Greece) wines (WD: white dry and WDS: white dry sparkling) were examined in terms of their quality (chemical, physicochemical and sensory) parameters. The concentration of alcohol in both wines was practically stable (p&gt;0.05) from the stage of fermentation to packaging and specifically, the rates were 12 and 11.4% vol for WD and WDS wines, respectively. Total sugar concentrations were equal to 1.4 g/l and 1.2 g/l in WD and WDS wines, respectively. WD wine had final total acidity, volatile acidity and pH values of 4.9 g/l tartaric acid, 0.19 g/l acetic acid and 3.15, respectively. While, WDS wine had final total acidity, volatile acidity and pH value of 6.0 g/l tartaric acid, 0.15 g/l acetic acid and 3.11, respectively. Τotal sulfite content of wine samples decreased and final values of 90.6 mg/l and 99.8 mg/l, in the last production stage, for the WD and WDS wines, were recorded, respectively. According to the data of the study, all wines received a high acceptability sensory score, as judged by the panellists. It must be reported that the sensory scores were on average, 1 point higher for the WDS wines, as compared to the WD wines.

PSVI-19 Effect of Processing Methods and Inclusion Level of Dried raw Garlic on in Vitro Fermentation Profile and Methane Production in a Corn Silage-Based Diet

Abstract Garlic (Allium sativum) contains secondary compounds known to modify rumen fermentation parameters and decrease methane (CH4) emissions; however, results from previous research on the effects of garlic-byproduct supplementation are quite variable. The objective of this experiment was to evaluate the effects of increasing inclusion levels and processing methods of dried raw garlic on in vitro ruminal fermentation and CH4 production. The experiment was designed as a randomized complete block design, where 24 h incubations were conducted on three separate days, with corn silage and gin trash (80:20, respectively) used as basal substrate. Treatments were arranged in a 3 × 3 factorial with garlic inclusion (0, 2.5, and 5% of the diet) and processing method (freeze-dried, oven-dried, and autoclaved) as factors. Three ruminally cannulated steers were fed ad libitum a corn silage and gin trash diet, for at least 35 d prior to collection of ruminal fluid used as inoculum. Final pH, concentration of volatile fatty acids (VFA) and ammonia nitrogen (NH3-N), in vitro organic matter digestibility (IVOMD), total gas production, and CH4 concentrations were determined at the end of incubation. Data were analyzed using the Mixed procedure of SAS. Final pH and concentration of total VFA were not affected (P &amp;gt; 0.05) by the processing method nor inclusion level of garlic. Increasing garlic inclusion decreased NH3-N concentration (P &amp;lt; 0.05), reduced (P &amp;lt; 0.05) the proportion of acetate, tended to increase (P &amp;lt; 0.10) the proportion of propionate, and tended to decrease (P &amp;lt; 0.10) the acetate:propionate ratio. Neither garlic inclusion level nor processing methods modified IVOMD, total gas production, or CH4 concentration. Modifications in VFA molar proportions and NH3-N concentration may be related to differences in N concentration in the incubated substrates. In conclusion, neither processing method nor garlic level inclusion modified CH4 production or nutrient digestibility.

A novel process of immobilizing sodium arsenate crystals as scorodite using Fe(OH)3 as an iron source

Sodium arsenate crystals are a hazardous waste produced from the utilization of arsenic–alkali residue in antimony metallurgy that pose a serious threat to the environment. In this article, to eradicate the damage caused by sodium arsenate and enhance the sustainable development of nonferrous metallurgy, a novel process was proposed to immobilize arsenic as flaky scorodite using Fe(OH)3 as an iron source. Various methods, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), and inductively coupled plasma atomic emission spectrometry (ICPAES), were applied to characterize these synthesized products. The whole process is divided into three parts. In the thermodynamic analysis, the stable area of scorodite in the Pourbaix diagram significantly expands at high ionic activity and temperature, which favors the decrease in △rG for scorodite synthesis, and Fe–As coprecipitation is feasible in solution at 0.18 ≤pH≤ 5.30. In the scorodite synthesis, 99.88% of the arsenic was converted to a flaky scorodite with a size of 2–5 µm by optimizing the parameters. In the removal of arsenic, residual arsenic and iron were completely coprecipitated into an iron salt by dropping NaOH solution to a final pH of 5.0. The final products include scorodite and sodium sulfate in this process. Overall, this new approach successfully eliminates the potential arsenic pollution from the utilization of arsenic–alkali residue in antimony metallurgy and can potentially be applied to dispose of other high arsenic-bearing wastes.

The Quality and Composition of Iranian Low-Salt UF-White Cheese

In cheese, the reduction of salt is still a challenging task, as sodium chloride exerts multiple and fundamental functions. Salt favors the drainage of the residual whey; enhances the taste and the aroma profile; regulates the texture, the final pH, and the water activity; and affects the microbial growth. Hence the impact of partial replacement of NaCl by KCl on the ripening characteristics of Iranian UF (ultrafiltration) cheese during storage was monitored. To produce low-salt cheese, different mixtures of UF white cheese were treated with NaCl : KCl ratios of (a) 3% NaCl (control), (b) 1.50% NaCl+1.50% KCl, (c) 1.00% NaCl+2.00% KCl, and (d) 0.75% NaCl+2.25% KCl by dry salting. ADV (acid degree value) results showed significant differences ( P &lt; 0.05 ) in all treatments after 15, 30, 40, and 50 days of ripening. No significant differences were observed in the GC (gas chromatography) results in the samples’ free fatty acid (FFA) profile except for C18 : 0 in all treatments. KCl did not affect the moisture, dry matter, fat, TN (total nitrogen)/dry matter, and WSN (water-soluble nitrogen) contents of cheeses considerably. The evaluation of force to fracture showed that there were significant differences ( P &lt; 0.05 ) between treatment (d) as a control cheese and treatments (b) and (c). Sensory evaluations showed as the concentration of KCl increased, the cheese gradually became less acceptable and treatments with higher potassium chloride content were crumblier and less firm. Results of the aroma evaluation of cheese samples showed that unlike acetaldehyde, ethanol, acetoin, and diacetyl amounts decreased significantly ( P &lt; 0.05 ) during the storage period. Results also indicated that a reduction of sodium by up to 50% did not significantly affect the quality and composition of Iranian low-salt UF-white cheese except for sensory evaluation, texture analysis, and aroma characteristics.

Active Dry Yeast and Thiamine in Synergistic Mode Can Mitigate Adverse Effects of In Vitro Ruminal Acidosis Model of Goats.

Simple SummarySubacute ruminal acidosis (SARA) is a most prevalent metabolic disorder of ruminants which poses a great threat to the health and wellbeing of animals. The purpose of this research was to induce SARA in in vitro conditions and to determine the potential of active dry yeast (ADT) and thiamine synergistically in mitigating the adverse effects of SARA. Both the supplements ADY and thiamine synergistically enhanced the ruminal pH, decreased the abundance of negative rumen bacteria and increased the abundance of useful rumen bacteria and protozoa. It was concluded that the combined use of ADY and thiamine as a supplement could mitigate SARA. SARA not only damages the health of the animals but also has detrimental effects on the economic conditions of the farmers. Therefore, this research could be beneficial for society.Ruminal acidosis is a type of metabolic disorder of high-yielding ruminants which is associated with the consumption of a high-grain diet. It not only harms the productive efficiency, health and wellbeing of the animals but also has detrimental effects on the economy of the farmers. Various strategies have been adapted to control ruminal acidosis. However, none of them have produced the desired results. This research was carried out to investigate the potential of active dry yeast (ADY) and thiamine in a synergistic mode to mitigate in vitro-induced ruminal acidosis. The purpose of this study was to determine how active dry yeast alone and in combination with thiamine affected the ruminal pH, lactate, volatile fatty acids, lipopolysaccharides (LPS) and microbial community in in vitro-induced ruminal acidosis. The experiment comprises three treatment groups, (1) SARA/control, (2) ADY and (3) ADYT (ADY + thiamine). In vitro batch fermentation was conducted for 24 h. The results indicated that ruminal induced successfully and both additives improved the final pH (p < 0.01) and decreased the LPS and lactate (p < 0.01) level as compared to the SARA group. However, the ADYT group decreased the level of lactate below 0.5 mmol/L. Concomitant to fermentation indicators, both the treatment groups decreased (p < 0.05) the abundance of lactate-producing bacteria while enhancing (p < 0.01) the abundance of lactate-utilizing bacteria. However, ADYT also increased (p < 0.05) the abundance of protozoa compared to the SARA and ADY group. Therefore, it can be concluded that ADY and thiamine in synergistic mode could be a better strategy in combating the adverse effects of subacute ruminal acidosis.