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1.
Curr Microbiol ; 81(1): 31, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38062219

RESUMEN

A formaldehyde-degrading bacterium JJ-2 was isolated from the rhizosphere of Chlorophytum and identified as Acinetobacter pittii by colony morphology and 16S rDNA sequence analysis. Further studies showed that under optimal conditions, JJ-2 could maintain activity for six cycles at an initial formaldehyde concentration of 450 mg L-1. At the same time, the complete degradation time was shortened from 12 to 6 h. When the JJ-2 strain was inoculated into sterile soil, the surface spray method had the best effect, and the removal efficiency of 5 ppm formaldehyde increased by 22.63%. In an actual potted plants system colonized with strain JJ-2, the first and second fumigations (without re-inoculation) increased removal by 1.36 times and 0.92 times during the day and 1.27 times and 2.07 times at night. In addition, in the second fumigation, the plant-bacteria combined system was 693.63 ppm and the plant system was 715.34 ppm, effectively reducing the CO2 concentration. This study provides an economical, ecological, and efficient approach to improve the combined system of plants and bacteria to remove gaseous formaldehyde from indoor air, with a positive impact on carbon neutrality.


Asunto(s)
Acinetobacter , Dióxido de Carbono , Dióxido de Carbono/metabolismo , Plantas , Acinetobacter/genética , Acinetobacter/metabolismo , Bacterias/metabolismo , Formaldehído/metabolismo , Biodegradación Ambiental
2.
J Biotechnol ; 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39128504

RESUMEN

This study investigated the use of endophyte-assisted Tillandsia brachycaulos to enhance formaldehyde removal in indoor environments. A formaldehyde-degrading endophyte from the root of Epipremnum aureum, Pseudomonas plecoglossicida, was identified and used for inoculation. Among the inoculation methods, spraying proved to be the most effective, resulting in a significant 35% increase in formaldehyde removal after 36hours. The results of the light exposure experiment (3000 Lux) demonstrate that an increase in light intensity reduces the efficiency of the Tillandsia brachycaulos-microbial system in degrading formaldehyde. In a 15-day formaldehyde fumigation experiment at 2 ppm in a normal indoor environment, the inoculated Tillandsia brachycaulos exhibited removal efficiency ranging from 42.53% to 66.13%, while the uninoculated declined from 31.62% to 3.17%. The Pseudomonas plecoglossicida (referred to as PP-1) became the predominant bacteria within the Tillandsia brachycaulos after fumigation. Moreover, the endophytic inoculation effectively increased the resistance and tolerance of Tillandsia brachycaulos to formaldehyde, as evidenced by lower levels of hydroxyl radical, malondialdehyde (MDA), free protein, and peroxidase activity (POD), as well as higher chlorophyll content compared to uninoculated Tillandsia brachycaulos. These findings indicate that the combination of endophytic bacteria and Tillandsia brachycaulos has significant potential for improving indoor air quality.

3.
Sci Total Environ ; 807(Pt 2): 150731, 2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-34634350

RESUMEN

Municipal solid waste incineration fly ash is classified as the hazardous waste because of its high levels of heavy metals alkali chlorides, and polychlorinated dibenzo-p-dioxins. Thermal treatment is widely used for fly ash treatment because of its advantages of reduction and harmless. The transformation behaviors of chlorine and metal ions during the thermal treatment of fly ash has a significant impact on the harmless and resource of fly ash. At present, the migration behaviors of chlorine and metal ions during thermal treatment of fly ash is not clearly demonstrated. In this manuscript, the phase compositions, transformation behaviors, the variation of mass and content of chlorine and various metal ions were analyzed through diverse characterization methods under different sintering temperatures to understand the migration behaviors of chlorine and metal ions during thermal treatment. Roasting experiments showed that the migration behaviors of heavy metals and chlorides were consistent. The chlorine, sodium, potassium and heavy metal ions can be removed sharply while the calcium, aluminum, magnesium and iron were decreased slightly when the roasting temperature was above 750 °C. The findings also suggested that removed chlorides were soluble chlorides and unstable crystals in municipal solid waste incineration fly ash were inclined to formed steady structure under high temperature. The structure of roasted fly ash became denser and generated ceramic-like particle due to thermal agglomeration and chemical reactions.


Asunto(s)
Cloro , Incineración , Cloruros , Ceniza del Carbón , Residuos Sólidos
4.
J Pharm Sci ; 108(10): 3194-3200, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31145921

RESUMEN

Pyroglutamic acid (pyroGlu) is commonly observed at the N-terminus of therapeutic monoclonal antibodies. Notably, the term "pyroGlu" refers to a single product that could originate from the cyclization of either an N-terminal glutamine or an N-terminal glutamic acid. This is an important and easily overlooked distinction that has major implications on the charge variant nature of a pyroGlu relative to its uncyclized form. Cyclization of an N-terminal glutamine for instance clearly produces an acidic variant with a lower isoelectric point owing to the loss of the positively charged N-terminal amine. In this report, we demonstrate that cyclization of an N-terminal glutamic acid on the other hand produces a basic variant with a higher isoelectric point contrary to the typical assumption that the simultaneous loss of the N-terminal amine and the carboxylic acid side-chain would negate the formation of a charge variant. The results of our investigation demonstrate the need to consider the relative strengths of the acidic and basic functional groups which are altered when assessing whether the product will be a charge variant. This study also adds new knowledge and experimental evidence to understand charge heterogeneity in monoclonal antibodies.


Asunto(s)
Anticuerpos Monoclonales/química , Ciclización/efectos de los fármacos , Ácido Glutámico/química , Ácido Pirrolidona Carboxílico/química , Glutamina/química
5.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1068-1069: 131-135, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29059588

RESUMEN

Establishing and maintaining the correct formulation composition is essential for ensuring the stability of biopharmaceutical drug products. A barrier to the routine assessment of excipient concentration is the lack of convenient and robust methods for the direct analysis of solutions containing high protein concentrations. To address this need an HPLC method was developed utilizing a wide-pore C18 guard column to trap proteins in-line with a hydrophilic interaction liquid chromatographic column to separate excipients. This method allows for a simple and direct analysis of excipients such as amino acids, carboxylic acids, simple carbohydrates, and inorganic ions across multiple drug formulations and process streams containing different therapeutic antibodies. The method was successfully validated for specificity, precision, accuracy, linearity, and robustness.


Asunto(s)
Anticuerpos Monoclonales/química , Cromatografía Liquida/métodos , Excipientes/análisis , Cromatografía Liquida/instrumentación , Excipientes/química , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Lineales , Porosidad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
6.
Dalton Trans ; 44(24): 11013-20, 2015 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-25994514

RESUMEN

It has been a challenge to decipher the in situ ligand reaction mechanism in assembly processes, involving metals and ligands. The present study shows two crystalline mixed-ligand Cu(II) coordination polymers isolated by controlled in situ ligand reactions under the same hydrothermal conditions. Two closely related examples provide a precious chance to access the in-depth mechanistic issues surrounding in situ reactions. The solid structure of 1 demonstrated that maleic acid was completely transformed to malic acid, whereas when fumaric acid was used in the same reaction conditions, an incomplete transformation from fumaric acid to malic acid was observed in the solid structure of 2. Compound 1 exhibits a 3D 6-connected sni network based on a binuclear copper(ii) secondary building unit, whereas the 3D network of 2 is classified to a (6,8)-connected topology network. The difference in steric hindrance between maleic acid and fumaric acid dictates the degree of the in situ nucleophilic addition reaction. The comparison of synthesis and final solid structures indicates that the one-step nucleophilic addition mechanism for in situ generated malic acid under the current reaction conditions of 1 is plausible. The magnetic sensitivity measurements of 1 demonstrated that overall antiferromagnetic coupling exists between Cu1 and Cu2 ions and between Cu3 and Cu4 ions. Furthermore, the obtained 1 can be an active catalyst for the solvent-free silylcyanation of aromatic aldehydes under mild conditions.

7.
J Biomed Mater Res A ; 66(4): 819-28, 2003 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-12926034

RESUMEN

Our aims in this study were (1) to develop an electrochemical method of depositing adherent octacalciumphosphate (OCP) and other calcium phosphate coatings on titanium alloy (Ti6Al4V) substrates of different shapes and surface preparations, (2) to determine the properties of the coating (composition, morphology, thickness, dissolution), and (3) to observe transformation of OCP to carbonatehydroxyapatite (CHA) in simulated body fluid (SBF). Titanium (Ti)-alloy plates, tensile bars with four types of surfaces (grit-blasted with apatitic abrasive, chemically textured, arc-deposited, and Co-Cr-beaded) and dissolution cylinders were electrochemically coated with the use of modulated pulse time electric fields programmed with a custom-made dual microprocessor. Modulated electrochemical deposition (MECD) was carried out with pH and temperature conditions favorable for OCP formation. Coatings were characterized using X-ray diffraction, FT-IR, scanning electron microscopy, tensile strength tests, and solubility tests. XRD and FT-IR analyses showed that pure, uniform OCP coatings were produced on Ti6Al4V surfaces with coating-to-substrate tensile strengths greater than 7,000 psi. Coatings on Ti arc-deposited surfaces, chemically textured surfaces, and Co-Cr-beaded surfaces all gave tensile strengths ranging from 5,000 to 7,000 psi, with no coating shadows in the crevices. Dissolution of OCP coating in 100 mL of 0.1 M Tris buffer solution was determined from the amount of calcium (Ca) released onto the buffer, which was 7.7 +/- 1.0 ppm Ca at pH 7.3 after 4 h, and 22 -/+ 1.4 ppm Ca at pH 3 after 2 h. We found that OCP crystal size can be controlled by the current density and relative pulse time modulation. Our study demonstrated the following: (1) Highly adherent calcium phosphate (e.g., OCP) coating of uniform compositions (e.g., OCP) on Ti-alloy substrates can be obtained at low temperatures with the use of MECD by optimizing pulse time modulation of the electric field, reaction pH, temperature, and electrolyte composition; and (2) OCP readily transforms to CHA when exposed to SBF.


Asunto(s)
Aleaciones , Fosfatos de Calcio/química , Electroquímica/métodos , Titanio , Cristalización , Solubilidad , Resistencia a la Tracción
8.
Am J Dent ; 16(3): 155-60, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12967067

RESUMEN

PURPOSE: To test the hypothesis that anticalculus agents cannot completely inhibit calculus formation but can influence the types of calcium phosphate which form, i.e., they can influence the composition of the inorganic component of human dental calculus (HDC). MATERIALS AND METHODS: The composition of HDC specimens obtained from a 16-week multi-center clinical study using three regimens were analyzed, investigators blinded. The treatment regimens were: (a) standard dentifrice (SD), (b) pyrophosphate antitartar dentifrice, and (c) SD with Tartar Control Listerine Antiseptic mouthrinse (containing essential oils and 0.09% zinc chloride). 25 individual samples and eight pooled samples from each group were analyzed using X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. RESULTS: (1) relative frequency of occurrence for: (a) bacteria: Group A = 100%, Group B = 60%, and Group C = 25%; (b) Carbonate hydroxyapatite (CHA): Groups A, B, and C = 100%; (c) dicalcium phosphate dihydrate (DCPD): Group A = 55%; Group B = 45%; Group C = 80%; (2) The relative amount of DCPD is inversely proportional to that of CHA in HDC: the higher the amount of DCPD, the lower the amount of CHA. Group C regimen with essential oil/ZnCl2 mouthrinse and standard dentifrice showed a significant anti-microbial effect and favored the formation of DCPD, the most soluble Ca-P.


Asunto(s)
Cloruros/uso terapéutico , Cálculos Dentales/química , Antisépticos Bucales/uso terapéutico , Aceites Volátiles/uso terapéutico , Compuestos de Zinc/uso terapéutico , Antiinfecciosos Locales/uso terapéutico , Bacterias/ultraestructura , Fosfatos de Calcio/análisis , Fosfatos de Calcio/clasificación , Dentífricos/uso terapéutico , Difosfatos/uso terapéutico , Método Doble Ciego , Durapatita/análisis , Humanos , Microscopía Electrónica de Rastreo , Compuestos Orgánicos , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
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