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1.
Sci Total Environ ; 865: 161122, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36587690

RESUMO

Fluorene (Flu) occurs widely in various environments and its toxicity to organisms is well-known. However, the impact of Flu on complicated biochemical processes involving functional microbial community has been reported rarely. In this study, the facilitation of Flu on the volatile fatty acids (VFAs) generation executed by acidogenic microbial population during sludge acidogenic fermentation (37 °C, SRT = 8 d, pH = 10.0) was investigated. The accumulation of VFAs (particularly acetic acid) increased initially and then declined with the increasing of Flu concentration (0-500 mg/kg dry sludge), which reached a maximum (3211.1 mg COD/L) as Flu content was 200 mg/kg dry sludge. The Flu-enhanced VFAs production was primarily attributed to the shift of hydrolysis/acidification, as well as the corresponding functional microbial community and the activity of enzymes. Based on the metagenomics analysis, the conversion of organic substrates, i.e. amino acid and monosaccharide, into VFAs embraced in hydrolysis/acidification shaped by Flu was constructed at the genetic level. The relative abundances of genes included in aminotransfer and deamination process of amino acid and glycolysis of monosaccharide into VFA-precursors (pyruvate, acetyl-CoA and propionyl-CoA), and the further formation of VFAs were improved due to the Flu presence. This study shed light on the Flu-affected microbial processes at the molecular biology level during acidogenic fermentation and was of great significance in resource recovery of sludge containing persistent organic pollutants.


Assuntos
Aminoácidos , Esgotos , Fermentação , Esgotos/química , Monossacarídeos , Ácidos Graxos Voláteis , Ácidos , Fluorenos , Concentração de Íons de Hidrogênio , Reatores Biológicos
2.
ACS Macro Lett ; 12(1): 93-100, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36595347

RESUMO

Surface coating is essential and critical to endow fiber materials with various functions for broad applications. However, it is still a great challenge to achieve a fast, fully covered, and robust surface coating on multiple fibers. In this work, a nanoscale surface coating with superior stability was rapidly and integrally formed on various fiber materials (such as Nylon mesh, nonwoven fabrics, and stainless-steel mesh) by highly reactive interfacial polymerization (IP) between polyethylenimine (PEI) and trimesoyl chloride (TMC). The resulting polyamide (PA) layer with an ultrathin thickness of tens of nanometers wholly and uniformly covered the surface of each fiber of the constituent material. Due to the synergistic effect of the PA layer with inherent robustness and the fully covered structure between the outer PA layer and the inner fiber, the nanosurface-coating exhibited outstanding mechanical stability, good acid resistance, and excellent organic solvent resistance. The functional modification of the nanosurface-coating can be easily carried out by using the abundant carboxyl groups in the PA layer. By introducing sulfobetaine zwitterionic copolymers via either "grafting from" or "grafting to" methods, the surfaces presented prominent underwater antioil-adhesion property and exceptional protein adhesion resistance. The surface coating based on IP process opens up an avenue in the field of surface modification. It is expected to offer a generally feasible strategy for the fabrication of fiber materials with robust and multifunctional coatings.


Assuntos
Nylons , Polímeros , Polimerização , Polímeros/química , Têxteis , Ácidos
3.
Anal Bioanal Chem ; 415(5): 749-758, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36622393

RESUMO

Electrospray ionization mass spectrometry (ESI-MS) experiments, including ion mobility spectrometry mass spectrometry (ESI-IMS-MS) and electron capture dissociation (ECD) of proteins ionized from aqueous solutions, have been used for the study of solution-like structures of intact proteins. By mixing aqueous proteins with denaturants online before ESI, the amount of protein unfolding can be precisely controlled and rapidly analyzed, permitting the characterization of protein folding intermediates in protein folding pathways. Herein, we mixed various pH solutions online with aqueous cytochrome C for unfolding and characterizing its unfolding intermediates with ESI-MS charge state distribution measurements, IMS, and ECD. The presence of folding intermediates and unfolded cytochrome c structures were detected from changes in charge states, arrival time distributions (ATDs), and ECD. We also compared structures from nondenaturing and denaturing solution mixtures measured under "gentle" (i.e., low energy) ion transmission conditions with structures measured under "harsh" (i.e., higher energy) transmission. This work confirms that when using "gentle" instrument conditions, the gas-phase cytochrome c ions reflect attributes of the various solution-phase structures. However, "harsh" conditions that maximize ion transmission produce extended structures that no longer correlate with changes in solution structure.


Assuntos
Citocromos c , Espectrometria de Mobilidade Iônica , Citocromos c/química , Elétrons , Proteínas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Desdobramento de Proteína , Ácidos , Íons/química , Água
4.
PLoS One ; 18(1): e0280412, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36656809

RESUMO

BACKGROUND: Excessive and irrational use of antibiotics as growth promoters in poultry has been one of key factors contributing to increased emergence of antibiotics resistant bacteria. Several alternatives for antibiotic growth promoters are being sought, and the search for effective probiotics to be used as feed additives is amongst the promising ones. Our study aimed to isolate and test potential probiotics bacteria from cloacal swabs of various indigenous chicken (Gallus domesticus) breeds from rural outskirts of the Kathmandu valley (Nepal). METHODS: Selective isolation of probiotics was conducted by micro-aerophilic enrichment of sample in MRS Broth at 37°C, followed by culturing on MRS agar supplemented with 5 g/L of CaCO3. Isolated bacterial colonies producing transparent halo were selected as potential lactic acid bacteria (LAB), and tested for their antibacterial activity, phenotypic and biochemical characteristics, acidic yield, and tolerance to acid and bile. RESULTS: A total of 90 potential LAB were isolated from cloacal samples collected from 41 free-ranging chickens of indigenous breeds. Of these, 52 LAB isolates (57%) showed variable antibacterial activity to at least one bacterial pathogen. Of 52 LAB, 46 isolates fulfilled phenotypic and biochemical criteria of Lactobacillus spp. Of these, 37 isolates produced varying percentage yields of lactic acid, 27 isolates showed survival at pH 3.0, and 17 isolates showed survival tolerances in the presence of 0.3% and 0.5% bile salts for 24 hours. Phylogenetic analysis of 16S rDNA sequencing of LAB isolates fulfilling in vitro probiotics properties showed that 3 isolates had genetic identity of 99.38% with Lactobacillus plantarum, while one isolate was genetically similar (99.85%) with the clade of L. reuteri, L. antri and L. panis. CONCLUSION: Our study identified four Lactobacillus spp. strains having potential probiotics properties. Further investigations are needed to evaluate these isolates to be used as poultry probiotics feed supplement.


Assuntos
Lactobacillales , Probióticos , Animais , Galinhas/microbiologia , Filogenia , Nepal , Lactobacillus , Antibacterianos/farmacologia , Aves Domésticas/genética , Ácidos/farmacologia , Probióticos/farmacologia , RNA Ribossômico 16S/genética
5.
Int J Mol Sci ; 24(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36675149

RESUMO

Macromolecules containing acidic fragments in side-groups-polyacids-occupy a special place among synthetic polymers. Properties and applications of polyacids are directly related to the chemical structure of macromolecules: the nature of the acidic groups, polymer backbone, and spacers between the main chain and acidic groups. The chemical nature of the phosphorus results in the diversity of acidic >P(O)OH fragments in sidechain phosphorus-containing polyacids (PCPAs) that can be derivatives of phosphoric or phosphinic acids. Sidechain PCPAs have many similarities with other polyacids. However, due to the relatively high acidity of -P(O)(OH)2 fragment, bone and mineral affinity, and biocompatibility, sidechain PCPAs have immense potential for diverse applications. Synthetic approaches to sidechain PCPAs also have their own specifics. All these issues are discussed in the present review.


Assuntos
Fósforo , Polímeros , Polímeros/química , Ácidos , Substâncias Macromoleculares , Ácidos Fosfínicos/química
6.
Food Res Int ; 163: 112157, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36596108

RESUMO

Natural polysaccharides were isolated and purified from Cucurbita moschata by hot water extraction and mild acid-base sequential extraction. Chemical and instrumental studies revealed that hot water-extracted and mild acid-extracted polysaccharides with molecular masses of 48 kDa and 85 kDa were both pectic polysaccharides with homogalacturonan (HG) and rhamnogalacturonan-I (RG-I) domains, while mild acid-extracted polysaccharide was more dominated by branched RG-I with higher contents of galactose (10.59 %) and arabinose (8.08 %). Furthermore, mild acid-extracted polysaccharide exhibited better thickening and emulsifying properties, likely due to its larger molecular mass and higher branching degree. Mild base-extracted polysaccharide with a molecular mass of 18 kDa was a glucan-like polysaccharide. It showed the strongest thermostability and gel behavior among these pumpkin polysaccharides, likely attributed to its unique network structure stabilized by substantial intra/intermolecular hydrogen bonds. This study aimed to establish the structure-property relationships between these structurally diverse pumpkin polysaccharides from different extraction methods and provided theoretical foundations for their targeted application in foods.


Assuntos
Cucurbita , Cucurbita/química , Polissacarídeos/química , Antioxidantes/química , Galactose , Ácidos , Água
7.
Molecules ; 28(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36615654

RESUMO

A series of novel 1-N-α-d-glucopyranosyl-1H-1,2,3-triazole xanthines was synthesized from azido sugars (glucose, galactose, and lactose) and propargyl xanthines (theophylline and theobromine) using a typical copper (I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition. The corrosion inhibition activities of these new carbohydrate-xanthine compounds were evaluated by studying the corrosion of API 5 L X70 steel in a 1 M HCl medium. The results showed that, at 10 ppm, a 90% inhibition efficiency was reached by electrochemical impedance spectroscopy. The inhibitory efficiency of these molecules is explained by means of quantum chemical calculations of the protonated species with the solvent effect, which seems to better represent the actual situation of the experimental conditions. Some quantum chemical parameters were analyzed to characterize the inhibition performance of the tested molecules.


Assuntos
Aço , Xantinas , Aço/química , Corrosão , Triazóis/farmacologia , Triazóis/química , Ácidos , Modelos Teóricos
8.
Sci Rep ; 13(1): 325, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609678

RESUMO

The global orange industry constantly faces new technical challenges to meet consumer demands for quality fruits. Instead of traditional subjective fruit quality assessment methods, the interest in the horticulture industry has increased in objective, quantitative, and non-destructive assessment methods. Oranges have a thick peel which makes their non-destructive quality assessment challenging. This paper evaluates the potential of short-wave NIR spectroscopy and direct sweetness classification approach for Pakistani cultivars of orange, i.e., Red-Blood, Mosambi, and Succari. The correlation between quality indices, i.e., Brix, titratable acidity (TA), Brix: TA and BrimA (Brix minus acids), sensory assessment of the fruit, and short-wave NIR spectra, is analysed. Mix cultivar oranges are classified as sweet, mixed, and acidic based on short-wave NIR spectra. Short-wave NIR spectral data were obtained using the industry standard F-750 fruit quality meter (310-1100 nm). Reference Brix and TA measurements were taken using standard destructive testing methods. Reference taste labels i.e., sweet, mix, and acidic, were acquired through sensory evaluation of samples. For indirect fruit classification, partial least squares regression models were developed for Brix, TA, Brix: TA, and BrimA estimation with a correlation coefficient of 0.57, 0.73, 0.66, and 0.55, respectively, on independent test data. The ensemble classifier achieved 81.03% accuracy for three classes (sweet, mixed, and acidic) classification on independent test data for direct fruit classification. A good correlation between NIR spectra and sensory assessment is observed as compared to quality indices. A direct classification approach is more suitable for a machine-learning-based orange sweetness classification using NIR spectroscopy than the estimation of quality indices.


Assuntos
Citrus sinensis , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Frutas/química , Análise dos Mínimos Quadrados , Ácidos/análise
9.
Sci Rep ; 13(1): 565, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36631517

RESUMO

Carbon fibers (CFs) of high quality were produced from hydrocarbons such as isobutane or ethylene using the catalytic chemical vapor deposition method (CCVD) and Ni catalyst. The as-prepared samples were functionalized with acidic groups using concentrated sulfuric acid or 4-benzenediazonium sulfonate (BDS) generated in situ from sulfanilic acid and sodium nitrite. The morphological features of the materials were confirmed by transmission electron microscopy, whereas their physicochemical properties were characterized by means of elemental and textural analyses, thermogravimetric (TG) method, Raman spectroscopy, potentiometric back titration, and X-ray diffraction analysis. The obtained CFs were used as catalysts in glycerol etherification with tert-butyl alcohol at 110 °C under autogenous pressure. The BDS-modified CFs were particularly effective in the reaction, showing high glycerol conversions (of about 45-55% after 6 h) and substantial yields of mono- and di-glycerol ethers. It was found that the chemistry of the sample surface was crucial for the process. The high concentration of -SO3H groups decorating CFs boosted the formation of di- and tri-tert-butyl glycerol ethers. Surface oxygen functionalities also had a positive effect on the reaction, however, their impact on the catalytic performances of CFs was significantly weaker compared to that shown by -SO3H groups and it was probably due to the adsorption of reagents on the catalyst surface.


Assuntos
Síndrome de Fadiga Crônica , Glicerol , Humanos , Glicerol/química , Fibra de Carbono , Éteres/química , Ácidos , Éteres de Glicerila
10.
Org Lett ; 25(2): 373-377, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36627725

RESUMO

The exchange of the metal ion from Zr(IV) to Fe(III) leads to a switch in the enantioselectivity of binary acid-catalyzed conjugate hydride reductions. In the presence of Hantzsch ester, γ-indolyl ß,γ-unsaturated α-keto esters could be reduced to the desired (S)- or (R)-products, respectively, with good to excellent enantioselectivity (up to 98% ee).


Assuntos
Ácidos , Compostos Férricos , Estereoisomerismo , Ésteres , Catálise
11.
Bioresour Technol ; 371: 128628, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36646357

RESUMO

Levulinic acid is a significant platform chemical obtained from biomass and can potentially be used to produce value-added biofuels, biopolymers, and biopharmaceuticals. This study aims at statistically optimizing levulinic acid production from agrowastes. Based on the total carbohydrate content (71.93 %), corncob was selected as the target feedstock. A Box-Behnken design with four factors, such as feedstock concentration, reaction time, reaction temperature, and catalyst concentration, was used to optimize the hydrothermal conversion of corncob to levulinic acid at 180 °C for 30 min using 1 M H2SO4 as the acid catalyst and 120 g/L corncob. The maximum yield of 19.9 % was obtained. Additionally, 8.1 g/L formic acid was co-produced. The results of this study can contribute toward valorization of levulinic acid. Moreover, our results can be useful in developing strategies to utilize agrowastes as a renewable feedstock for recent biorefineries to cope with the climate crisis.


Assuntos
Ácidos Levulínicos , Zea mays , Temperatura , Ácidos , Biomassa
12.
Artigo em Inglês | MEDLINE | ID: mdl-36674251

RESUMO

Microtube microfilter with organic phosphoric acid (expressed as MF-OP) containing a wastewater portion with buffer fluid and an enriched portion with nitric acid fluid and organic phosphoric extractant dissolved in benzin has been studied for its trivalent holmium (expressed as Ho(III) collection from rare earth wastewater. Common parameters affecting the collection effect have been investigated, including hydrogen ion molar concentration (molar concentration can be expressed as Cm) or pH value, initial concentration (expressed as Co) of Ho(III), ion-force of rare earth wastewater, voluminal proportion of organic phosphoric extractant with benzin and nitric acid fluid (expressed as Vr), nitric acid Cm, extractant Cm, and type of acid fluid in an enriched portion. The virtues of MF-OP compared to the traditional collection was explored. The impacts of hydrodynamic characteristics (steadiness and current speed) and MF parameter factors (inradius of tube, tube-shell thickness, proportion of holes) on the collection performance of MF-OP for Ho(III) collection were also considered. The test results displayed that the greatest collection conditions of Ho(III) were attained as nitric acid Cm was 4.00 mol/L, extractant Cm was 0.220 mol/L, and Vr was 0.8 in the enriched portion, and pH value was 4.60 in the wastewater portion. Ion- force of rare earth wastewater had no noticeable outcome on Ho(III) collection. The collection proportion of Ho(III) was attainable to 93.1% in 280 min, while Co was 1.80 × 10-3 mol/L.


Assuntos
Hólmio , Metais Terras Raras , Ácido Nítrico , Solventes , Compostos Orgânicos , Ácidos , Mineração
13.
Int J Mol Sci ; 24(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36674704

RESUMO

Proton-pump inhibitors (PPI), e.g., omeprazole or pantoprazole, are the most widely used drugs for various gastrointestinal diseases. However, more and more side effects, especially an increased risk of infections, have been reported in recent years. The underlying mechanism has still not yet been fully uncovered. Hence, in this study, we analyzed the T cell response after treatment with pantoprazole in vitro. Pantoprazole preincubation reduced the production and secretion of interferon (IFN)-γ and interleukin (IL)-2 after the T cells were activated with phytohemagglutinin (PHA)-L or toxic shock syndrome toxin-1 (TSST-1). Moreover, a lower zinc concentration in the cytoplasm and a higher concentration in the lysosomes were observed in the pantoprazole-treated group compared to the untreated group. We also tested the expression of the zinc transporter Zrt- and Irt-like protein (Zip)8, which is located in the lysosomal membrane and plays a key role in regulating intracellular zinc distribution after T cell activation. Pantoprazole reduced the expression of Zip8. Furthermore, we measured the expression of cAMP-responsive element modulator (CREM) α, which directly suppresses the expression of IL-2, and the expression of the phosphorylated cAMP response element-binding protein (pCREB), which can promote the expression of IFN-γ. The expression of CREMα was dramatically increased, and different isoforms appeared, whereas the expression of pCREB was downregulated after the T cells were treated with pantoprazole. In conclusion, pantoprazole downregulates IFN-γ and IL-2 expression by regulating the expression of Zip8 and pCREB or CREMα, respectively.


Assuntos
Interleucina-2 , Inibidores da Bomba de Prótons , Inibidores da Bomba de Prótons/farmacologia , Pantoprazol/farmacologia , 2-Piridinilmetilsulfinilbenzimidazóis/farmacologia , Zinco/farmacologia , Linfócitos T , Ácidos
14.
J Environ Manage ; 330: 117148, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36584458

RESUMO

Bioremediation techniques utilizing sulfate-reducing bacteria (SRB) for acid mine drainage (AMD) treatment have attracted growing attention in recent years, yet substrate bioavailability for SRB is a key factor influencing treatment effectiveness and long-term stability. This study investigated the effects of external organic substrates, including four complex organic wastes (i.e., sugarcane bagasse, straw compost, shrimp shell (SS), and crab shell (CS)) and a small-molecule organic acid (i.e., propionate), on AMD removal performance and associated microbial communities during the 30-day operation of sulfate-reducing microcosms. The results showed that the pH values increased in all five microcosms, while CS exhibited the highest neutralization ability and a maximum alkalinity generation of 1507 mg/L (as CaCO3). Sulfate reduction was more effective in SS and CS microcosms, with sulfate removal efficiencies of 95.6% and 86.0%, respectively. All sulfate-reducing microcosms could remove heavy metals to different degrees, with the highest removal rate of >99.0% observed for aluminum. The removal efficiency of manganese, the most recalcitrant metal, was the highest (96%) in the CS microcosm. Correspondingly, SRB was more abundant in the CS and SS microcosms as revealed by sequencing analysis, while Desulfotomaculum was the dominant SRB in the CS microcosm, accounting for 10.8% of total effective bacterial sequences. Higher abundances of functional genes involved in fermentation and sulfur cycle were identified in CS and SS microcosms. This study suggests that complex organic wastes such as CS and SS could create and maintain preferable micro-environments for active growth and metabolism of functional microorganisms, thus offering a cost-efficient, stable, and environmental-friendly solution for AMD treatment and management.


Assuntos
Desulfovibrio , Metais Pesados , Microbiota , Saccharum , Celulose , Sulfatos/química , Metais Pesados/química , Ácidos , Desulfovibrio/metabolismo , Reatores Biológicos/microbiologia
15.
J Environ Manage ; 327: 116901, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36481690

RESUMO

Fungal mash derived from Aspergillus spp. is a green enzymatic additive for food waste (FW) valorization. In this study, the production of volatile fatty acids (VFAs) and the proportion of propionic acid (PA) in VFAs were increased by utilizing a complex enzyme (CE) obtained from Aspergillus oryzae. Results showed that CE addition significantly promoted SCOD concentration in the hydrolysis at a wide pH range from 4 to 9. In contrast, the production of VFAs was influenced by pH, and the highest yields of VFAs and PA were found at pH 7. At the CE dosage of 0.2 g/g VSS, the concentration of VFAs in the FW fermentation liquid reached 38.1 g COD/L with the PA proportion up to 42.7%, which increased by 107.9% and 63.7%, respectively, relative to that in the zero-dosage group. With CE continuing to be added, the C/N ratio declined, and the primary metabolic pathway was converted from acetic acid-type to PA-type. Further investigation of the dominant microbial communities and their metabolic capacities showed that the acrylate-mediated pathway was the potential metabolic reaction in PA-type fermentation. These results indicated that CE pretreatment was a feasible strategy to enhance the PA-rich fermentation of FW under neutral pH conditions.


Assuntos
Alimentos , Eliminação de Resíduos , Fermentação , Propionatos , Ácidos Graxos Voláteis , Ácidos , Concentração de Íons de Hidrogênio , Esgotos , Reatores Biológicos/microbiologia , Anaerobiose
16.
Bioresour Technol ; 370: 128515, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36538957

RESUMO

Microalgae have become the hotspot of recent researches as heavy metals (HMs) adsorbent and biodiesel production feedstock. In this study, the cell growth, lipid production and Cr6+ removal of Parachlorella kessleri R-3 at pH 3.5 and 15 °C were investigated. It was found that low concentration of Cr6+ (0.5 to 2 mg/L) promoted the algal growth, whereas Cr6+ higher than 5 mg/L inhibited the growth of P. kessleri R-3. Biomass concentration (2.40 g/L) and lipid productivity (131.79 mg/L d-1) reached the highest at 2 mg/L Cr6+, and lipid content (61.03 %) reached the highest at 5 mg/L Cr6+. The maximum Cr6+ removal efficiency of 91 % was obtained at 0.5 mg/L Cr6+ treatment. Furthermore, fatty acid composition analysis showed that strain R-3 had a high C16-18 content of 74.88-89.21 %. This study provides new insight into the treatment of HMs and lipid production in cold regions.


Assuntos
Metais Pesados , Microalgas , Cromo , Biocombustíveis , Temperatura , Ácidos Graxos , Ácidos , Biomassa
17.
Appl Environ Microbiol ; 89(1): e0169922, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36511659

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a threat to human health. Acidic electrolyzed water (AEW) has recently been suggested to demonstrate virucidal activity. Many types of AEW with different pH values, generated by the electrolysis of different chemicals, such as sodium chloride, potassium chloride, and hydrochloric acid, are commercially available. In this study, we compared the virucidal activities of these types of AEW against SARS-CoV-2, including the ancestral strain and variant Alpha, Beta, Gamma, Delta, and Omicron strains. Virus solution (viral titer, 6.9 log10 50% tissue culture infective dose [TCID50]/mL) was mixed with AEW (free available chlorine concentration, 34.5 ppm) at mixing ratios of 1:9, 1:19, and 1:49. At mixing ratios of 1:9 and 1:19, AEW with a pH of 2.8 showed stronger virucidal activities than AEW with a pH of 4.1 to 6.5 against the SARS-CoV-2 ancestral strain in 20 s. From the strongest to the weakest virucidal activity, the AEW pH levels were as follows: pH 2.8, pH 4.1 to 5.4, pH 6.4 to 6.5. At a ratio of 1:49, the viral titers of viruses treated with all AEW solutions at pH 2.8 to 6.5 were almost below the detection limit, which was 1.25 log10 TCID50/mL. The virus inactivation efficiency of AEW was reduced in the presence of fetal bovine serum and other substances contained in the virus solution used in this study. AEW with pH values of 2.8 to 6.5 showed virucidal activity against all of the tested SARS-CoV-2 strains, including the ancestral and variant strains. These results provide useful knowledge for the effective application of AEW as a SARS-CoV-2 disinfectant. IMPORTANCE Acidic electrolyzed water (AEW) demonstrates virucidal activity against multiple viruses. Since AEW exhibits low toxicity, is inexpensive, and is environmentally friendly, it can be a useful disinfectant against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although the pH values of currently available AEW products vary, the impact of different pH values on SARS-CoV-2 inactivation has not previously been evaluated in detail. In this study, we compared the virucidal activities of multiple AEW solutions with different pH values, under the same experimental conditions. We found that AEW solutions with lower pH values demonstrated more potent virucidal activity. Also, we showed that the extent of virus inactivation by the AEW was based on the balance of the abundance of free available chlorine, virus, and other organic substances in the mixture. AEW exhibited rapid virucidal activity against multiple SARS-CoV-2 strains. This study demonstrated the usefulness of AEW as a disinfectant which can be applied to the inactivation of SARS-CoV-2.


Assuntos
COVID-19 , Desinfetantes , Humanos , SARS-CoV-2 , Cloro/química , Desinfetantes/farmacologia , Água/química , Ácidos , Concentração de Íons de Hidrogênio
18.
J Agric Food Chem ; 71(1): 592-602, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36562625

RESUMO

Corn stover was subjected to dilute sulfuric acid pretreatment to assess the impact of pretreatment conditions on lignin extractability, properties, and utility as a phenol replacement in wood phenol-formaldehyde (PF) adhesives. It was identified that both formic acid and NaOH could extract and recover 60-70% of the lignin remaining after pretreatment and enzymatic hydrolysis under the mildest pretreatment conditions while simultaneously achieving reasonable enzymatic hydrolysis yields (>60%). The availability of reaction sites for the incorporation of lignins into the PF polymer matrix (i.e., unsubstituted phenolic hydroxyl groups) was shown to be strongly impacted by the pretreatment time and the recovery. Finally, a lignin-based wood adhesive was formulated by replacing 100% of the phenol with formic-acid-extracted lignin, which exhibited a dry shear strength exceeding a conventional PF adhesive. These findings suggest that both pretreatment and lignin extraction conditions can be tailored to yield lignins with properties targeted for this co-product application.


Assuntos
Lignina , Fenol , Adesivos , Madeira , Fenóis , Ácidos , Formaldeído , Hidrólise
19.
Food Chem ; 408: 135200, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36528990

RESUMO

The acidic pH and total amount of SO2 are both important quality control indexes of wine, but conventional detection techniques depend heavily on specialized instrument and professional staff, thus are not available to general customers. In this paper, a hemicyanine-based colorimetric and fluorescent probe Hcy-Py was designed and synthesized. It responded to bisulfite selectively with a LOD of 0.68 µM and responded to proton with a pKa of 3.78. Upon the treatment of solutions with different pH values and concentrations of bisulfite, the probe-loaded paper strips displayed distinct color changes under both natural light and UV lamp. When a real white wine sample was subjected to the paper strip experiment, pH as well as bisulfite concentration could be determined by naked-eye quickly and conveniently, thus a visual detection of acidic pH and bisulfite in white wine without involving any sophisticated instrument or professional skill was successfully demonstrated.


Assuntos
Corantes Fluorescentes , Vinho , Humanos , Colorimetria/métodos , Vinho/análise , Ácidos , Concentração de Íons de Hidrogênio
20.
Food Chem ; 408: 135140, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36549158

RESUMO

Sodium caseinate is a well-known amphiphilic protein derived from natural products currently used for the preparation of edible films. To improve some properties, especially to decrease the hydrophilicity and water solubility of the caseinate, the covalent grafting of a hydrophobic edible fatty acid, namely oleic acid, onto caseinate, appears to be a solution. We describe a new synthesis method for the chemical modification of sodium caseinate involving the synthesis of an acid chloride derivative from oleic acid and a phase transfer catalysis reaction in a biphasic medium. Under these conditions, free amine and alcohol groups of the caseinate are likely to be grafted with a fairly high (>50 %) substitution degree. The caseinate derivative is finely characterized, in particular by DOSY NMR, to assess the formation of a casein/oleic acid grafted compound as well as the absence of residual oleic acid.


Assuntos
Caseínas , Ácido Oleico , Caseínas/química , Ácidos Graxos , Solubilidade , Ácidos
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