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1.
J Sci Food Agric ; 99(15): 6911-6921, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31393604

RESUMEN

BACKGROUND: This study aimed to evaluate the possibility of cotton waste enrichment with glycine betaine (GB) for production of two strains (P9, P10) of king oyster (Pleurotus eryngii). Cotton waste was used as (100%) control (T0 = cotton waste) and augmented with various combinations of GB, (T1 = 2 mmol L-1 , T2 = 4 mmol L-1 , T3 = 6 mmol L-1 , T4 = 8 mmol L-1 and T5 = 10 mmol L-1 ). The response of king oyster to GB was evaluated by earliness, yield, biological efficiency (BE), minerals (nitrogen, phosphorus, potassium, zinc (Zn), copper (Cu), magnesium (Mg), manganese (Mn), iron (Fe), sodium (Na), calcium (Ca)), total sugars, total soluble solids, reducing sugars, non-reducing sugars, ascorbic acid, proximate (crude protein, carbohydrates, crude fibers, ash, fats) content of fruiting body and Fourier-transform infrared (FTIR) spectroscopy analysis compared with the control substrate (cotton waste). RESULTS: The earliness, yield, and BE were higher as compared to control substrate and increased with an augmentation in the concentration of GB within the cotton waste. Two strains showed (on dry weight basis) 33.9-54.9 mg g-1 nitrogen, 6.8-12.5 mg g-1 phosphorus, 16.9-25.1 mg g-1 potassium, 40.5-64.2 mg kg-1 Zn, 17.1-37.3 mg kg-1 Cu, 1174-1325 mg kg-1 Mg, 20.1-29.1 mg kg-1 Mn, 129-265 mg kg-1 Fe, 779-835 mg kg-1 Ca), 6.3%-11.3% total sugars, 7.3-14.9 °Brix total soluble solids, 2.1-7.3% reducing sugars, 10.4-18.1% crude protein, 3.6-4.4% crude fiber and 5.6-16.7 mg (100 g)-1 on various concentration of GB enrich cotton waste. Cotton waste enriched with GB significantly affected nutritional profile of king oyster mushroom. CONCLUSION: The results revealed that GB enriched cotton waste can be used as an innovative substrate to enhance the yield and quality of king oyster mushroom. © 2019 Society of Chemical Industry.


Asunto(s)
Betaína/metabolismo , Medios de Cultivo/metabolismo , Glicina/metabolismo , Gossypium/microbiología , Pleurotus/química , Pleurotus/metabolismo , Residuos/análisis , Betaína/análisis , Medios de Cultivo/química , Glicina/análisis , Gossypium/metabolismo , Minerales/metabolismo , Nitrógeno/análisis , Nitrógeno/metabolismo , Fósforo/análisis , Fósforo/metabolismo , Pleurotus/genética , Pleurotus/crecimiento & desarrollo
2.
Appl Environ Microbiol ; 80(17): 5467-76, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24973068

RESUMEN

1,2,3-Trichloropropane (TCP) is a toxic compound that is recalcitrant to biodegradation in the environment. Attempts to isolate TCP-degrading organisms using enrichment cultivation have failed. A potential biodegradation pathway starts with hydrolytic dehalogenation to 2,3-dichloro-1-propanol (DCP), followed by oxidative metabolism. To obtain a practically applicable TCP-degrading organism, we introduced an engineered haloalkane dehalogenase with improved TCP degradation activity into the DCP-degrading bacterium Pseudomonas putida MC4. For this purpose, the dehalogenase gene (dhaA31) was cloned behind the constitutive dhlA promoter and was introduced into the genome of strain MC4 using a transposon delivery system. The transposon-located antibiotic resistance marker was subsequently removed using a resolvase step. Growth of the resulting engineered bacterium, P. putida MC4-5222, on TCP was indeed observed, and all organic chlorine was released as chloride. A packed-bed reactor with immobilized cells of strain MC4-5222 degraded >95% of influent TCP (0.33 mM) under continuous-flow conditions, with stoichiometric release of inorganic chloride. The results demonstrate the successful use of a laboratory-evolved dehalogenase and genetic engineering to produce an effective, plasmid-free, and stable whole-cell biocatalyst for the aerobic bioremediation of a recalcitrant chlorinated hydrocarbon.


Asunto(s)
Contaminantes Ambientales/metabolismo , Ingeniería Metabólica , Propano/análogos & derivados , Pseudomonas putida/genética , Pseudomonas putida/metabolismo , Biodegradación Ambiental , Biotransformación , Elementos Transponibles de ADN , Expresión Génica , Hidrolasas/genética , Hidrolasas/metabolismo , Redes y Vías Metabólicas/genética , Plásmidos , Propano/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Selección Genética
3.
Int J Biol Macromol ; 256(Pt 1): 128285, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38007018

RESUMEN

The peels of Trapa natans (TRA) and Citrullus lanatus (CIT), were modified with a variety of chemicals to boost their surface for the optimization of adsorption performance by providing a greater number of additional active binding sites. Citric acid-processed peels (TRAC and CITC) had shown more favorable adsorption performance to eradicate acid violet 7 dye (AVS). Extra and additional active sites generated after chemical processing, including hydroxyl (OH), carboxyl (COOH), amines NH2, carbonyl, and ester (-O-CO-) groups, as evidenced from FTIR and SEM characterizations, may boost the potential of physicochemical integration of adsorbent surface activity in order to promote and encourage the retention of hazardous and risky AVS molecules from the water. The Langmuir isotherm assessed the qmax for the adsorption of AVS on TRAC, CITC, TRA, and CIT to be 212.8, 294, 24.3, and 60.6 mg/g, respectively, whereas the correlation coefficients assessed for both TRAC and CITC were 0.98 and for TRA and CIT were 0.97, closer to unity reflecting monolayer physio-sorption. According to Temkin, the adsorption of AVS on TRAC, TRA, CITC, and CIT gives "BT" values of 1.275, 0.947, 1.085, and 1.211 mg/g, also suggesting physio-sorption. Therefore, chemically modified peels can be employed for detoxification of AVS.


Asunto(s)
Compuestos Azo , Citrullus , Lythraceae , Naftalenosulfonatos , Contaminantes Químicos del Agua , Adsorción , Ácido Cítrico , Contaminantes Químicos del Agua/química , Cinética , Concentración de Iones de Hidrógeno
4.
RSC Adv ; 13(38): 26455-26474, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37674490

RESUMEN

Persistent organic pollutants and dyes cause major problems during ecofriendly wastewater treatment. To overcome this huge problem, several techniques have been considered and in practice for the safe disposal of organic pollutants in recent years; some of them are discussed and compared herein. This review focuses on new trends for wastewater treatment and compares them with certain other techniques alongside their pros and cons; adsorption is considered the safest among them. Adsorbents derived from agri-wastes have good capacity for the removal of these contaminants owing to their great sorption capacity, high reusability, easy operation, etc. Sometimes they need some modifications for the removal of dyes, which are also discussed in this review. This capacity of adsorbents to chelate dye molecules can be affected by factors, such as pH, the concentration of dyes and adsorbents, and temperature of the system. pH has direct influence on the ionization potential and charge on the outer surface of adsorbents. The findings on isotherms, kinetics, and desorption of plant waste-based biomaterials that are safe for the ecosystem and user friendly and are used for hazardous contaminant removal from water are summarized in this review. Finally, conclusions and future perspectives are presented, and some other materials, such as CNTs and MOFs, are also discussed as efficient adsorbents for eliminating dyes from wastewater. Finally, it is predicted that the adsorption of dyes is a more feasible solution for this dye pollution problem.

5.
Int J Anal Chem ; 2023: 9914633, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37090056

RESUMEN

A novel pressurized flow system for circular thin-layer chromatography (PC-TLC) has been successfully established and employed for the separation of amino acids, dyes, and pigments for safe medical imaging applications. In this system, the mobile phase is applied to a regular TLC plate through the tube and needle of an intravenous infusion set. The needle was fused in a hole underneath the center of the plate, while the second side end of the tube was connected to a microburette containing the solvent. This new assembly proved itself better in terms of separation time (within 5 minutes) and controlled flow of the solvent and horizontal movement of analyte components over chromatograms with better separation and R f values (glutamine: 0.26, valine: 0.44, phenylalanine: 0.60, chlorophyll a: 0.52, chlorophyll b: 0.43, xanthophyll: 0.18, carotenoid: 0.97, and pheophytin: 0.60) when a number of samples of amino acids, dyes, and pigments were separated by the developed apparatus and the conventional TLC procedure. The developed method was found distinctly rapid, precise, and eco-friendly (less solvent consuming) as compared to traditional ascending TLC.

6.
Appl Environ Microbiol ; 78(17): 6128-36, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22752160

RESUMEN

A Pseudomonas putida strain (MC4) that can utilize 2,3-dichloro-1-propanol (DCP) and several aliphatic haloacids and haloalcohols as sole carbon and energy source for growth was isolated from contaminated soil. Degradation of DCP was found to start with oxidation and concomitant dehalogenation catalyzed by a 72-kDa monomeric protein (DppA) that was isolated from cell lysate. The dppA gene was cloned from a cosmid library and appeared to encode a protein equipped with a signal peptide and that possessed high similarity to quinohemoprotein alcohol dehydrogenases (ADHs), particularly ADH IIB and ADH IIG from Pseudomonas putida HK. This novel dehalogenating dehydrogenase has a broad substrate range, encompassing a number of nonhalogenated alcohols and haloalcohols. With DCP, DppA exhibited a k(cat) of 17 s(-1). (1)H nuclear magnetic resonance experiments indicated that DCP oxidation by DppA in the presence of 2,6-dichlorophenolindophenol (DCPIP) and potassium ferricyanide [K(3)Fe(CN)(6)] yielded 2-chloroacrolein, which was oxidized to 2-chloroacrylic acid.


Asunto(s)
Clorhidrinas/metabolismo , Oxidorreductasas/metabolismo , Pseudomonas putida/enzimología , Pseudomonas putida/metabolismo , Acroleína/análogos & derivados , Acroleína/metabolismo , Carbono/metabolismo , Clonación Molecular , ADN Bacteriano/química , ADN Bacteriano/genética , Metabolismo Energético , Cinética , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Oxidorreductasas/genética , Señales de Clasificación de Proteína , Pseudomonas putida/genética , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Especificidad por Sustrato
7.
Appl Microbiol Biotechnol ; 95(2): 511-20, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22101783

RESUMEN

A pure bacterial culture able to utilize 2-fluorophenol (2-FP) as sole carbon and energy source was isolated by selective enrichment from sediments collected from a contaminated site in Northern Portugal. 16S rRNA gene analysis showed that the organism (strain FP1) belongs to the genus Rhodococcus. When grown aerobically on 2-FP, growth kinetics of strain FP1 followed the Luong model. An inhibitory effect of increasing 2-FP concentrations was observed with no growth occurring at 2-FP levels higher than ca. 4 mM. Rhodococcus strain FP1 was able to degrade a range of other organofluorine compounds, including 2-fluorobenzoate, 3-fluorobenzoate, 4-fluorobenzoate, 3-fluorophenol, 4-fluorophenol, 3-fluorocatechol, and 4-fluorocatechol, as well as chlorinated compounds such as 2-chlorophenol and 4-chlorophenol. Experiments with cell-free extracts and partially purified enzymes indicated that the first step of 2-fluorophenol metabolism was conversion to 3-fluorocatechol, suggesting an unusual pathway for fluoroaromatic metabolism. To our knowledge, this is the first time that utilization of 2-FP as a growth substrate by a pure bacterial culture is reported.


Asunto(s)
Fenoles/metabolismo , Rhodococcus/aislamiento & purificación , Rhodococcus/metabolismo , Biotransformación , Carbono/metabolismo , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Metabolismo Energético , Microbiología Ambiental , Contaminantes Ambientales/metabolismo , Redes y Vías Metabólicas , Datos de Secuencia Molecular , Filogenia , Portugal , ARN Ribosómico 16S/genética , Rhodococcus/crecimiento & desarrollo , Análisis de Secuencia de ADN
8.
Microb Drug Resist ; 28(1): 106-119, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34402682

RESUMEN

The multidrug resistance (MDR) Escherichia coli having Extended-Spectrum Beta-Lactamase (ESBL) genes and the capacity to create a biofilm acts as a major reduction in the therapeutic effectiveness of antimicrobials. In search of a novel nanocarrier (NC) for targeted delivery of antibiotics, carbon dots (CDs) coated calcium carbonate nanocarriers (CCNC) from organic chicken eggshells conjugated with levofloxacin (Lvx) were synthesized. Our main objectives were to explore the antimicrobial, antibiofilm, and NC potential of CDs coated CaCO3 Nanocarrier conjugated with levofloxacin (CD-CCNC-Lvx) to combat biofilm-producing MDR ESBL E. coli of urinary tract infection origin. The synthesized NC system was physiochemically characterized, validating the synthesis of CCNC and CD-CCNC-Lvx with a particle size of 56 and 14 nm, respectively. Scanning electron microscopy (SEM) showed rod shape morphology. X-ray diffraction results discovered crystalline and dispersed nanoparticles. In vitro release drug kinetics illustrated sustained release of Lvx. NC system exhibited strong antibacterial and antibiofilm potential against E. coli with a noticeable low minimal inhibitory concentration (MIC). MIC of CCNC was found to be 30 ± 0.1 µg/mL and CD-CCNC-Lvx was 20 ± 0.1 µg/mL for MDR ESBL-producing E. coli. The synergistic effect of NC upon conjugation with Lvx showed incredible activity with 30 mm zone of inhibition and 68% biofilm inhibition. Flow cytometry analysis revealed treated E. coli cells showed 58.69% reduction in cell viability. SEM images of treated bacterial cells showed morphological changes, which were also confirmed by our flow cytometry findings leading to cell membrane damage in E. coli. NC system also downregulated the blaCTX-M gene in E. coli. The hemolytic analysis proved biocompatibility with human red blood cells (RBCs). It is concluded that CCNC has the potential to be used as NC for target delivery of antibiotics and may combat toxicity of antibiotics as the inhibition of E. coli was noticed at low MIC concentration.


Asunto(s)
Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Infecciones por Escherichia coli/tratamiento farmacológico , Levofloxacino/uso terapéutico , Puntos Cuánticos/química , Infecciones Urinarias/tratamiento farmacológico , Antibacterianos/administración & dosificación , Apoptosis/efectos de los fármacos , Biopelículas/efectos de los fármacos , Carbono , Liberación de Fármacos , Escherichia coli/genética , Infecciones por Escherichia coli/genética , Humanos , Levofloxacino/administración & dosificación , Pruebas de Sensibilidad Microbiana , Tecnología Farmacéutica , beta-Lactamasas/genética
9.
J Pharm Sci ; 110(10): 3471-3483, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34126118

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA)-induced mastitis is one of the biggest animal welfare issues and economic burdens worldwide. As a possible effective treatment, ciprofloxacin (CIP)-loaded cerium oxide (CeO2)/chitosan (CS) nanocomposite was synthesized using an eco-friendly approach, characterized, and evaluated. From 350 mastitis-positive milk samples, 35 mecA-positive MRSA strains were confirmed by antibiotic sensitivity testing and PCR. CeO2 nanoparticles (NPs) were synthetized using the seeds' extract of Amomum subulatum (aka black cardamom/BC) as a reducing and capping agent, which was conjugated with CS by ionic gelation before CIP was nanoencapsulated. The resulting NPs were characterized physically (by using FESEM, TEM, EDS, XRD, FTIR, ZP, and UV-Vis spectrophotometry), biologically and pharmacologically (through in-vitro/ex-vivo antibacterial, cytotoxic, and drug release behavior assays). The CIP-nanocomposite was represented by pure, stable, small, pseudospherical NPs of crystalline nature. FTIR confirmed the surface linkage of CS and CIP in CeO2 NPs. CIP-CeO2/CS nanocarrier exerted enhanced antibacterial activity at lower MIC (8 µg/mL) compared to that of free CIP drug alone. Also, they were hemocompatible and not hepatotoxic. CIP release from the nanocarrier was better sustained in physiological-like conditions. Taken together, the phytogenic CIP-CeO2/CS nanocarrier could be considered as a potent and safe therapeutic solution for MRSA-induced mastitis.


Asunto(s)
Quitosano , Mastitis , Staphylococcus aureus Resistente a Meticilina , Animales , Antibacterianos/farmacología , Cerio , Ciprofloxacina , Femenino , Humanos
10.
Environ Sci Pollut Res Int ; 19(8): 3067-78, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22875418

RESUMEN

PURPOSE: 1,2,3-Trichloropropane (TCP) is a persistent groundwater pollutant and a suspected human carcinogen. It is also is an industrial chemical waste that has been formed in large amounts during epichlorohydrin manufacture. In view of the spread of TCP via groundwater and its toxicity, there is a need for cheap and efficient technologies for the cleanup of TCP-contaminated sites. In situ or on-site bioremediation of TCP is an option if biodegradation can be achieved and stimulated. This paper presents an overview of methods for the remediation of TCP-contaminated water with an emphasis on the possibilities of biodegradation. CONCLUSIONS: Although TCP is a xenobiotic chlorinated compound of high chemical stability, a number of abiotic and biotic conversions have been demonstrated, including abiotic oxidative conversion in the presence of a strong oxidant and reductive conversion by zero-valent zinc. Biotransformations that have been observed include reductive dechlorination, monooxygenase-mediated cometabolism, and enzymatic hydrolysis. No natural organisms are known that can use TCP as a carbon source for growth under aerobic conditions, but anaerobically TCP may serve as electron acceptor. The application of biodegradation is hindered by low degradation rates and incomplete mineralization. Protein engineering and genetic modification can be used to obtain microorganisms with enhanced TCP degradation potential.


Asunto(s)
Carcinógenos/metabolismo , Propano/análogos & derivados , Contaminantes del Agua/metabolismo , Animales , Bacterias/genética , Bacterias/metabolismo , Biodegradación Ambiental , Carcinógenos/toxicidad , Humanos , Ingeniería Metabólica/métodos , Propano/metabolismo , Propano/toxicidad , Ingeniería de Proteínas , Contaminantes del Agua/toxicidad , Zinc/química , Zinc/metabolismo
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