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1.
Int J Mol Sci ; 25(10)2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38791348

RESUMEN

Hybrid nanomaterials have attracted considerable interest in biomedicine because of their fascinating characteristics and wide range of applications in targeted drug delivery, antibacterial activity, and cancer treatment. This study developed a gelatin-coated Titanium oxide/palladium (TiO2/Pd) hybrid nanomaterial to enhance the antibacterial and anticancer capabilities. Morphological and structural analyses were conducted to characterize the synthesized hybrid nanomaterial. The surface texture of the hybrid nanomaterials was examined by high-resolution transmission electron microscopy (HR-TEM) and field-emission scanning electron microscopy (FE-SEM). The FE-SEM image revealed the bulk of the spherically shaped particles and the aggregated tiny granules. Energy dispersive X-ray spectroscopy (EDS) revealed Ti, Pd, C, and O. X-ray diffraction (XRD) revealed the gelatin-coated TiO2/Pd to be in the anatase form. Fourier transform infrared spectroscopy examined the interactions among the gelatin-coated TiO2/Pd nanoparticles. The gelatin-coated TiO2/Pd nanomaterials exhibited high antibacterial activity against Escherichia coli (22 mm) and Bacillus subtilis (17 mm) compared to individual nanoparticles, confirming the synergistic effect. More importantly, the gelatin-coated TiO2/Pd hybrid nanomaterial exhibited remarkable cytotoxic effects on A549 lung cancer cells which shows a linear increase with the concentration of the nanomaterial. The hybrid nanomaterials displayed higher toxicity to cancer cells than the nanoparticles alone. Furthermore, the cytotoxic activity against human cancer cells was verified by the generation of reactive oxygen species and nuclear damage. Therefore, gelatin-coated TiO2/Pd nanomaterials have potential uses in treating cancer and bacterial infections.


Asunto(s)
Antibacterianos , Antineoplásicos , Escherichia coli , Gelatina , Nanoestructuras , Paladio , Titanio , Titanio/química , Titanio/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Gelatina/química , Paladio/química , Paladio/farmacología , Escherichia coli/efectos de los fármacos , Nanoestructuras/química , Células A549 , Bacillus subtilis/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Difracción de Rayos X , Nanopartículas del Metal/química
2.
Biotechnol Appl Biochem ; 69(3): 867-875, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33811671

RESUMEN

In this work, a nickel ferrite (NiFe2 O4 )/nitrogen-doped-graphene (NG)/cellulose composite (NiFe2 O4 /NG/cellulose) was successfully synthesized through a facile chemical route, and its antibacterial potential was evaluated. The synthesized NiFe2 O4 /NG/cellulose composite was characterized by performing morphological and structural analyses. The results showed the successful formation of NiFe2 O4 -nanoparticles with a spherical shape and a size ranging from 15 to 200 nm. Energy-dispersive X-ray results confirmed the presence of various elements (carbon, nitrogen, oxygen, iron, and nickel) in the reaction mixture. The X-ray diffraction pattern showed the face-centered-cubic nature of the particles. In addition, antibacterial activity against Escherichia coli (Gram-negative bacteria) and Bacillus subtilis (Gram-positive bacteria) was evaluated with different concentrations of NiFe2 O4 /NG/cellulose composite (0-50 µg/mL). Inhibitory activity increased with increasing concentrations of NiFe2 O4 /NG/cellulose. The composite's inhibitory activity was slightly higher in E. coli than in B. subtilis due to the differing nature of their cell wall structures. Overall, the chemically synthesized NiFe2 O4 /NG/cellulose composite has the potential as an efficient antibacterial agent for controlling the growth of pathogenic bacteria.


Asunto(s)
Grafito , Nanopartículas del Metal , Nanocompuestos , Antibacterianos/química , Bacillus subtilis , Celulosa/química , Celulosa/farmacología , Escherichia coli , Grafito/química , Nanopartículas del Metal/química , Nanocompuestos/química , Nitrógeno
3.
Biotechnol Appl Biochem ; 69(2): 714-725, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33751641

RESUMEN

Overuse of antibiotics has led to the development of multidrug-resistant strains. Antibiotic resistance is a major drawback in the biomedical field since medical implants are prone to infection by biofilms of antibiotic resistant strains of bacteria. With increasing prevalence of antibiotic-resistant pathogenic bacteria, the search for alternative method is utmost importance. In this regard, magnetic nanoparticles are commonly used as a substitute for antibiotics that can circumvent the problem of biofilms growth on the surface of biomedical implants. Iron oxide nanoparticles (IONPs) have unique magnetic properties that can be exploited in various ways in the biomedical applications. IONPs are engineered employing different methods to induce surface functionalization that include the use of polyethyleneimine and oleic acid. IONPs have a mechanical effect on biofilms in presence of an external magnet. In this review, a detailed description of surface-engineered magnetic nanoparticles as ideal antibacterial agents is provided, accompanied by various methods of literature review.


Asunto(s)
Biopelículas , Nanopartículas , Antibacterianos/farmacología , Nanopartículas Magnéticas de Óxido de Hierro
4.
Mikrochim Acta ; 188(6): 185, 2021 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-33977395

RESUMEN

An abdominal aortic aneurysm (AAA) is abnormal swelling in the abdominal aorta and a prevalent life-threatening disease. This research introduces a new interdigitated microelectrode (IDME)-sensing surface modified by iron oxide nanoworms (IONWs) for detecting the AAA biomarker insulin-like growth factor-1 (IGF1). A sandwich pattern was formulated with the IGF1 aptamer and IGFBP1 (IGF binding protein-1) on the IONW-constructed IDME hybrid to identify IGF1. The surface morphology of the IONWs revealed a uniform distribution of worm-like structures (80-100 nm) as confirmed by FESEM and FETEM analyses. Further, the presence of the major elements, Fe and O, was confirmed by EDX and XPS studies. The crystal planes that appeared in the IONW reflect cubic magnetite. IONW-modified IDME attained a limit of detection for IGF1 of 1 fM (3σ) with an aptamer-IGF1-IGFBP1 sandwich. This sandwich with IGFBP1 enhanced the current level at all concentrations of IGF1 and displayed linearity in the range 1 fM to 100 pM with a determination coefficient of R2 = 0.9373 [y = 3.38221x - 4.79]. Control experiments with complementary aptamer sequences, IGF2 and IGFBP3 did not show notable signal changes, indicating the specific detection of IGF1. This IONW constructed electrode helps to achieve the detection of low amounts of IGF1 and diagnose AAA at the stage prior to rupture.


Asunto(s)
Aneurisma de la Aorta Abdominal/diagnóstico , Factor I del Crecimiento Similar a la Insulina/análisis , Nanoestructuras/química , Aneurisma de la Aorta Abdominal/sangre , Aptámeros de Nucleótidos/química , Biomarcadores/sangre , Biomarcadores/química , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Compuestos Ferrosos/química , Humanos , Ácidos Nucleicos Inmovilizados/química , Factor I del Crecimiento Similar a la Insulina/química , Límite de Detección , Microelectrodos
5.
Mikrochim Acta ; 188(6): 187, 2021 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-33990848

RESUMEN

A new zeolite-iron oxide nanocomposite (ZEO-IO) was extracted from waste fly ash of a thermal power plant and utilized for capturing aptamers used to quantify the myocardial infarction (MI) biomarker N-terminal prohormone B-type natriuretic peptide (NT-ProBNP); this was used in a probe with an integrated microelectrode sensor. High-resolution microscopy revealed that ZEO-IO displayed a clubbell structure and a particle size range of 100-200 nm. Energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy confirmed the presence of Si, Al, Fe, and O in the synthesized ZEO-IO. The limit of detection for NT-ProBNP was 1-2 pg/mL (0.1-0.2 pM) when the aptamer was sandwiched with antibody and showed the doubled current response even at a low NT-ProBNP abundance. A dose-dependent interaction was identified for this sandwich with a linear plot in the concentration range 1 to 32 pg/mL (0.1-3.2 pM) with a determination coefficient R2 = 0.9884; y = 0.8425x-0.5771. Without  sandwich, the detection limit was 2-4 pg/mL (0.2-0.4 pM) and the determination coefficient was R2 = 0.9854; y = 1.0996x-1.4729. Stability and nonfouling assays in the presence of bovine serum albumin, cardiac troponin I, and myoglobin revealed that the aptamer-modified surface is stable and specific for NT-Pro-BNP. Moreover, NT-ProBNP-spiked human serum exhibited selective detection. This new nanocomposite-modified surface helps in detecting NT-Pro-BNP and diagnosing MI at stages of low expression.


Asunto(s)
Técnicas Biosensibles/métodos , Nanocompuestos/química , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Zeolitas/química , Anticuerpos Inmovilizados/inmunología , Aptámeros de Nucleótidos/química , Secuencia de Bases , Biomarcadores/sangre , Biomarcadores/química , Técnicas Biosensibles/instrumentación , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Humanos , Ácidos Nucleicos Inmovilizados/química , Compuestos de Hierro/química , Límite de Detección , Microelectrodos , Infarto del Miocardio/sangre , Infarto del Miocardio/diagnóstico , Péptido Natriurético Encefálico/química , Péptido Natriurético Encefálico/inmunología , Óxidos/química , Fragmentos de Péptidos/química , Fragmentos de Péptidos/inmunología , Reproducibilidad de los Resultados
6.
Mikrochim Acta ; 188(8): 257, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34268634

RESUMEN

A label-free chemical bonding strategy mediated by reduced graphene oxide (rGO) basal plane functional groups has been developed for cardiac Troponin I (cTnI) detection. Four different chemical strategies on respective electrode sensing surface were precedingly examined using electrochemical impedance spectroscopy. The impedimetric assessment was carried out by sweeping frequency at the range 0.1-500 kHz perturbated at a small amplitude of AC voltage (25 mV). The chemical strategy-4 denoted as S-4 shows a significant analytical performance on cTnI detection in spiked buffer and human serum, whereby the pre-mixture of rGO and (3-Aminopropyl)triethoxysilane (APTES) creates a large number of amine sites (-NH2), which significantly enhanced the antibody immobilization without excessive functionalization. The as-fabricated immunosensor exhibited an ultra-low limit of detection of 6.3 ag mL-1 and the lowest antigen concentration measured was at 10 ag mL-1. The immunosensor showed a linear and wide range of cTnI detection (10 ag mL-1-100 ng mL-1) in human serum with a regression coefficient of 0.9716, rapid detection (5 min of binding time), and stable and highly reproducible bioelectrode response with RSD < 5%. Hence, the demonstrated S-4 strategy is highly recommended for other downstream biosensors applications.


Asunto(s)
Biomarcadores/sangre , Oro/química , Grafito/química , Troponina I/sangre , Técnicas Biosensibles , Espectroscopía Dieléctrica , Compuestos Epoxi/química , Humanos , Hidróxidos/química , Inmunoensayo , Cinética , Límite de Detección , Microelectrodos , Nanoestructuras , Propilaminas/química , Silanos/química , Propiedades de Superficie
7.
Molecules ; 26(9)2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-34063685

RESUMEN

Multidrug resistant bacteria create a challenging situation for society to treat infections. Multidrug resistance (MDR) is the reason for biofilm bacteria to cause chronic infection. Plant-based nanoparticles could be an alternative solution as potential drug candidates against these MDR bacteria, as many plants are well known for their antimicrobial activity against pathogenic microorganisms. Spondias mombin is a traditional plant which has already been used for medicinal purposes as every part of this plant has been proven to have its own medicinal values. In this research, the S. mombin extract was used to synthesise AgNPs. The synthesized AgNPs were characterized and further tested for their antibacterial, reactive oxygen species and cytotoxicity properties. The characterization results showed the synthesized AgNPs to be between 8 to 50 nm with -11.52 of zeta potential value. The existence of the silver element in the AgNPs was confirmed with the peaks obtained in the EDX spectrometry. Significant antibacterial activity was observed against selected biofilm-forming pathogenic bacteria. The cytotoxicity study with A. salina revealed the LC50 of synthesized AgNPs was at 0.81 mg/mL. Based on the ROS quantification, it was suggested that the ROS production, due to the interaction of AgNP with different bacterial cells, causes structural changes of the cell. This proves that the synthesized AgNPs could be an effective drug against multidrug resistant bacteria.


Asunto(s)
Anacardiaceae/química , Antibacterianos/farmacología , Biopelículas , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Nanopartículas del Metal/química , Plata/química , Animales , Artemia , Bacterias/efectos de los fármacos , Tecnología Química Verde , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Nanomedicina , Extractos Vegetales/farmacología , Hojas de la Planta/química , Especies Reactivas de Oxígeno , Rayos Ultravioleta
8.
Prep Biochem Biotechnol ; 51(1): 86-95, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32713293

RESUMEN

A chemical method to synthesize amorphous silica nanoparticles from the incinerated paddy straw has been introduced. The synthesis was conducted through the hydrolysis by alkaline-acidic treatments. As a result, silica particles produced with the sizes were ranging at 60-90 nm, determined by high-resolution microscopy. The crystallinity was confirmed by surface area electron diffraction. Apart from that, chemical and diffraction analyses for both rice straw ash and synthesized silica nanoparticles were conducted by X-ray diffraction and Fourier-transform infrared spectroscopy. The percentage of silica from the incinerated straw was calculated to be 28.3. The prominent surface chemical bonding on the generated silica nanoparticles was with Si-O-Si, stretch of Si-O and symmetric Si-O bonds at peaks of 1090, 471, and 780 cm-1, respectively. To confirm the impurities of the elements in the produced silica, were analyzed using X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy. The stability of silica nanoparticles was investigated using thermogravimetric analysis and zeta potential. The measured size from zeta potential analysis was 411.3-493 nm and the stability of mass reduction was located at 200 °C with final amount of mass reduced ∼88% and an average polydispersity Index was 0.195-0.224.


Asunto(s)
Ceniza del Carbón/química , Contaminantes Ambientales/química , Incineración , Nanopartículas/química , Oryza , Tallos de la Planta , Dióxido de Silicio/química , Residuos , Cristalización , Malasia , Tamaño de la Partícula , Espectroscopía de Fotoelectrones , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
9.
Biomed Microdevices ; 22(4): 67, 2020 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-32940771

RESUMEN

Nanoscale materials have been employed in the past 2 decades in applications such as biosensing, therapeutics and medical diagnostics due to their beneficial optoelectronic properties. In recent years, silver nanoparticles (AgNPs) have gained attention due to their higher plasmon excitation efficiency than gold nanoparticles, as proved by sharper and stronger plasmon resonance peaks. The current work is focused on utilizing self-assembled DNA-AgNPs on microdevices for the detection of gynecological cancers. Human papilloma virus (HPV) mostly spreads through sexual transmittance and can cause various gynecological cancers, including cervical, ovarian and endometrial cancers. In particular, oncogene E7 from the HPV strain 16 (HPV-16 E7) is responsible for causing these cancers. In this research, the target sequence of HPV-16 E7 was detected by an AgNP-conjugated capture probe on a dielectrode sensor. The detection limit was in the range between 10 and 100 aM (by 3σ estimation). The sensitivity of the AgNP-conjugated probe was 10 aM and similar to the sensitivity of gold nanoparticle conjugation sensors, and the mismatched control DNA failed to detect the target, proving selective HPV detection. Morphological assessments on the AgNPs and the sensing surfaces by high-resolution microscopy revealed the surface arrangement. This sensing platform can be expanded to develop sensors for the detection various clinically relevant targets.


Asunto(s)
ADN/química , Neoplasias de los Genitales Femeninos/diagnóstico , Nanopartículas del Metal/química , Microtecnología/instrumentación , Plata/química , Electrodos , Femenino , Humanos , Límite de Detección
10.
Prep Biochem Biotechnol ; 50(10): 1053-1062, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32597353

RESUMEN

This research comprehends iron-oxide nanoparticle (IONP) production, the apparent metallic nanostructure with unique superparamagnetic properties. Durian-rind-extract was utilized to synthesize IONP and the color of reaction mixture becomes dark brown, indicated the formation of IONPs and the peak was observed at ∼330 nm under UV-visible spectroscopy. The morphological observation under high-resolution microscopies has revealed the spherical shape and the average size (∼10 nm) of IONP. The further support was rendered by EDX-analysis showing apparent iron and oxygen peaks. XRD results displayed the crystalline planes with (110) and (300) planes at 2θ of 35.73° and 63.53°, respectively. XPS-data has clearly demonstrated the presence of Fe2P and O1s peaks. The IONPs were successfully capped by the polyphenol compounds from durian-rind-extract as evidenced by the representative peaks between 1633 and 595 cm-1 from FTIR analysis. The antimicrobial potentials of IONPs were evidenced by the disk-diffusion assay. The obtained results have abundant attention and being actively explored owing to their beneficial applications.


Asunto(s)
Antibacterianos/química , Bombacaceae/química , Tecnología Química Verde , Nanopartículas Magnéticas de Óxido de Hierro/química , Extractos Vegetales/química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Nanopartículas Magnéticas de Óxido de Hierro/ultraestructura , Nanotecnología
11.
Mikrochim Acta ; 186(8): 546, 2019 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-31321546

RESUMEN

A genomic DNA-based colorimetric assay is described for the detection of the early growth factor receptor (EGFR) mutation, which is the protruding reason for non-small cell lung cancer. A DNA sequence was designed and immobilized on unmodified gold nanoparticles (GNPs). The formation of the respective duplex indicates the presence of an EGFR mutation. It is accompanied by the aggregation of the GNPs in the presence of monovalent ions, and it indicates the presence of an EGFR mutation. This is accompanied by a color change from red (520 nm) to purple (620 nm). Aggregation was evidenced by transmission electron microscopy, scanning electron microscopy and atomic force microscopy. The limit of detection is 313 nM of the mutant target strand. A similar peak shift was observed for 2.5 µM concentrations of wild type target. No significant peak shift was observed with probe and non-complementary DNA. Graphical abstract Schematic representation of high-specific genomic DNA sequence on gold nanoparticle (GNP) aggregation with sodium chloride (NaCl). It illustrates the detection method for EGFR mutation on lung cancer detection. Red and purple colors of tubes represent dispersed and aggregated GNP, respectively.


Asunto(s)
ADN de Cadena Simple/química , Receptores ErbB/genética , Oro/química , Nanopartículas del Metal/química , Carcinoma de Pulmón de Células no Pequeñas/genética , Colorimetría , Neoplasias Pulmonares/genética , Mutación
12.
Molecules ; 23(12)2018 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-30551671

RESUMEN

In the present study, we have developed a green approach for the synthesis of silver nanoparticles (DSAgNPs) using aqueous extract of Durio zibethinus seed and determined its antibacterial, photocatalytic and cytotoxic effects. Surface plasmon resonance confirmed the formation of DSAgNPs with a maximum absorbance (λmax) of 420 nm. SEM and TEM images revealed DSAgNPs were spherical and rod shaped, with a size range of 20 nm and 75 nm. The zeta potential was found to be -15.41 mV. XRD and EDX analyses confirmed the nature and presence of Ag and AgCl. DSAgNPs showed considerable antibacterial activity, exhibited better cytotoxicity against brine shrimp, and shown better photocatalytic activity against methylene blue. Based on the present research work, it can be concluded that DSAgNPs could be used in the field of water treatment, pharmaceuticals, biomedicine, biosensor and nanotechnology in near future.


Asunto(s)
Antiinfecciosos/farmacología , Bombacaceae/química , Tecnología Química Verde/métodos , Luz , Nanopartículas del Metal/química , Extractos Vegetales/química , Semillas/química , Plata/química , Animales , Artemia/efectos de los fármacos , Catálisis , Muerte Celular/efectos de los fármacos , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana
13.
Bioprocess Biosyst Eng ; 39(3): 429-39, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26721574

RESUMEN

A halotolerant bacterial isolate-MHC10 with broad spectrum antibacterial activity against clinical pathogens was isolated from saltpans located in Tuticorin and Chennai (India). 16S rRNA gene analysis of MHC10 revealed close similarity to that of Bacillus methylotrophicus. The culture conditions of B. methylotrophicus MHC10 strain were optimized for antibacterial production using different carbon and nitrogen sources, as well as varying temperature, pH, sodium chloride (NaCl) concentrations and incubation periods. The maximum antibacterial activity of B. methylotrophicus MHC10 was attained when ZMB was optimized with 1 % (w/v) glucose, 0.1 % (w/v) soybean meal which corresponded to a C/N ratio of 38.83, temperature at 37 °C, pH 7.0 and 8 % NaCl. The activity remained stable between 72 and 96 h and then drastically decreased after 96 h. Solvent extraction followed by chromatographic purification steps led to the isolation of hydroquinone (benzene-1,4-diol). The structure of the purified compound was elucidated based on FTIR, (1)H NMR, and (13)C NMR spectroscopy. The compound exhibited efficient antibacterial activity against both Gram-positive and Gram-negative bacterial pathogens. The minimum inhibitory concentration (MIC) for Gram-positive pathogens ranged from 15.625 to 62.5 µg/mL(-1), while it was between 7.81 and 250 µg/mL(-1) for Gram-negative bacterial pathogens. This is the first report of hydroquinone produced by halotolerant B. methylotrophicus exhibiting promising antibacterial activity.


Asunto(s)
Antibacterianos , Bacillus/metabolismo , Hidroquinonas , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/metabolismo , Antibacterianos/farmacología , Hidroquinonas/química , Hidroquinonas/aislamiento & purificación , Hidroquinonas/metabolismo , Hidroquinonas/farmacología
14.
Biotechnol Appl Biochem ; 61(5): 528-34, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24397298

RESUMEN

In this study, seven lipase-producing bacterial strains were isolated from salt-enriched and cattle farm soil samples after incubation in toluene- and benzene-enriched media. One strain (PAL05) showed significantly greater lipase activity on spirit blue agar medium and stability in organic solvents. The positive strain (PAL05) was identified as Bacillus licheniformis by 16S rRNA gene sequencing. Lipase production was optimized in a medium containing glycerol as the carbon source and Tween 80 as an inducer (0.5% glycerol+0.5% Tween 80) at pH 8.0 and a temperature of 30 °C. In addition, the enzyme was moderately halotolerant as it exhibited increased activity in the presence of 2.5% NaCl. Optimized conditions increased the lipase production threefold. Crude lipase retained its activity for 14 days of incubation in the presence of various organic solvents at a level of 25% and 50%. The enzyme was stable at 25% in most solvents; some of the solvents such as hexane, benzene, and ethanol actually stimulated enzyme activity. The organic solvent stability of the lipase produced by the strain PAL05 enables the enzyme to be used as a potential biocatalyst for ester synthesis and other applications in nonaqueous conditions.


Asunto(s)
Bacillus/enzimología , Proteínas Bacterianas/química , Lipasa/química , Microbiología del Suelo , Bacillus/clasificación , Bacillus/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Carbono/metabolismo , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Lipasa/metabolismo , Compuestos Orgánicos , Filogenia , Cloruro de Sodio , Solventes , Temperatura
15.
J Ind Microbiol Biotechnol ; 41(2): 265-73, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24113891

RESUMEN

We previously completed whole-genome sequencing of a rare actinomycete named Sebekia benihana, and identified the complete S. benihana cytochrome P450 complement (CYPome), including 21 cytochrome P450 hydroxylase (CYP), seven ferredoxin (FD), and four ferredoxin reductase (FDR) genes. Through targeted CYPome disruption, a total of 32 S. benihana CYPome mutants were obtained. Subsequently, a novel cyclosporine A region-specific hydroxylase was successfully determined to be encoded by a CYP-sb21 gene by screening the S. benihana CYPome mutants. Here, we report that S. benihana is also able to mediate vitamin D3 (VD3) hydroxylation. Among the 32 S. benihana CYPome mutants tested, only a single S. benihana CYP mutant, ΔCYP-sb3a, failed to show regio-specific hydroxylation of VD3 to 25-hydroxyvitamin D3 and 1α,25-dihydroxyvitamin D3. Moreover, the VD3 hydroxylation activity in the ΔCYP-sb3a mutant was restored by CYP-sb3a gene complementation. Since all S. benihana FD and FDR disruption mutants maintained VD3 hydroxylation activity, we conclude that CYP-sb3a, a member of the bacterial CYP107 family, is the only essential component of the in vivo regio-specific VD3 hydroxylation process in S. benihana. Expression of the CYP-sb3a gene exhibited VD3 hydroxylation in the VD3 non-hydroxylating Streptomyces coelicolor, implying that the regio-specific hydroxylation of VD3 is carried out by a specific P450 hydroxylase in S. benihana.


Asunto(s)
Actinomycetales/genética , Colecalciferol/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Genoma Bacteriano , Oxigenasas de Función Mixta/genética , Actinomycetales/metabolismo , Secuencia de Aminoácidos , Sistema Enzimático del Citocromo P-450/metabolismo , Hidroxilación , Oxigenasas de Función Mixta/metabolismo , Datos de Secuencia Molecular , Streptomyces coelicolor/genética , Streptomyces coelicolor/metabolismo
16.
Prep Biochem Biotechnol ; 44(3): 266-80, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24274015

RESUMEN

Screening using spirit blue agar revealed that strain BK-L07 had the highest lipase activity. Furthermore, the isolated strain was identified as Pseudomonas sp. based on morphological, physiological, biochemical, and molecular analyses. The 16S rRNA gene sequence of strain BK-L07 shared a high similarity with that of Pseudomonas koreensis (99%). The nutritional conditions and physicochemical properties were influenced by P. koreensis BK-L07. The maximum lipase production was obtained in tryptic soy broth medium at pH 8.0 and a temperature of 25°C after 36 hr of incubation. In addition, the lipase activity was determined using different carbon sources and lipase inducers. The lipase production was greatest when 1% maltose was used as the carbon source and olive oil was used as the lipase inducer. The lipase production was significantly increased approximately threefold in the optimized medium when compared with the original medium. Further, the lipase was purified by ammonium sulfate precipitation and gel filtration chromatography with a purification yield of 10.8%. The molecular mass of lipase was 45 kDa. The optimum temperature and pH were 40°C and 8.0, respectively. The enzyme was stable up to 50°C and at pH from 7 to 9. In addition, the enzyme activity was stimulated by MgSO4 and completely inhibited by ethylenediamine tetraacetic acid (EDTA), indicating the metalloenzyme type. The lipase activity was toward medium to long chain length of fatty acids (C10 to C18). Supplemental materials are available for this article. Go to the publisher's online edition of Preparative Biochemistry and Biotechnology to view the supplemental file.


Asunto(s)
Lipasa/metabolismo , Pseudomonas/enzimología , Microbiología del Suelo , Concentración de Iones de Hidrógeno , Lipasa/aislamiento & purificación , Metales/metabolismo , Pseudomonas/aislamiento & purificación , Especificidad por Sustrato , Tensoactivos/metabolismo
17.
Heliyon ; 10(11): e31851, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38845893

RESUMEN

Cervical cancer is caused by changes in the cervix that lead to precancerous cells and eventually progress to cancer. Human papillomavirus (HPV) infections are the primary cause of cervical cancer. Early detection of HPV is crucial in preventing cervical cancer, and regular screening for HPV infection can identify cell changes before they develop into cancer. While Pap smear tests are reliable for cervical cancer screening, they are critical, expensive, and labor-intensive. Therefore, researchers are focusing on identifying blood-based biomarkers using biosensors for cervical cancer screening. HPV strains 16, 45, and 18 are common culprits in cervical cancer. This study aimed to develop an HPV-16 DNA biosensor on a zeolite-iron oxide (zeolite-IO) modified interdigitated electrode (IDE) sensor. The DNA probe was immobilized on the IDE through amine-modified zeolite-IO, enhancing the hybridization of the target and DNA probe. The detection limit of the DNA-DNA duplex was found to be 7.5 pM with an R2 value of 0.9868. Additionally, control experiments with single and triple mismatched sequences showed no increase in current responses, and the identification of target DNA in a serum-spiked sample indicated specific and selective target identification.

18.
Int J Biol Macromol ; 260(Pt 1): 129324, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38228210

RESUMEN

In the rapidly evolving landscape of silver nanoparticles (Ag NPs) synthesis, the focus has predominantly been on plant-derived sources, leaving the realm of biological or animal origins relatively uncharted. Breaking new ground, our study introduces a pioneering approach: the creation of Ag NPs using marine fish collagen, termed ClAg NPs, and offers a comprehensive exploration of their diverse attributes. To begin, we meticulously characterized ClAg NPs, revealing their spherical morphology, strong crystalline structure, and average diameter of 5 to 100 nm. These NPs showed potent antibacterial activity, notably against S. aureus (gram-positive), surpassing their efficacy against S. typhi (gram-negative). Additionally, ClAg NPs effectively hindered the growth of MRSA biofilms at 500 µg/mL. Impressively, they demonstrated substantial antioxidant capabilities, out performing standard gallic acid. Although higher concentrations of ClAg NPs induced hemolysis (41.804 %), lower concentrations remained non hemolytic. Further evaluations delved into the safety and potential applications of ClAg NPs. In vitro cytotoxicity studies on HEK 293 and HeLa cells revealed dose-dependent toxicity, with IC50 of 75.28 µg/mL and 79.13 µg/mL, respectively. Furthermore, ClAg NPs affected seed germination, root, and shoot lengths in Mung plants, underscoring their relevance in agriculture. Lastly, zebrafish embryo toxicity assays revealed notable effects, particularly at 500 µg/mL, on embryo morphology and survival rates at 96 hpf. In conclusion, our study pioneers the synthesis and multifaceted evaluation of ClAg NPs, offering promise for their use as versatile nano therapeutics in the medical field and as high-value collagen-based nanobiomaterial with minimal environmental impact.


Asunto(s)
Nanopartículas del Metal , Plata , Animales , Humanos , Plata/química , Nanopartículas del Metal/química , Pez Cebra , Células HeLa , Staphylococcus aureus , Células HEK293 , Antibacterianos/farmacología , Antibacterianos/química
19.
Biotechnol Appl Biochem ; 60(2): 155-61, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23586399

RESUMEN

The novel protease from Exiguobacterium profundum BK-P23 was partially purified by ammonium sulfate precipitation and further purified Mono Q 5/50 and Superdex 200 10/300 column chromatography. The enzyme was purified 10.23-fold with a yield of 14%. The molecular weight was estimated to be 52 kDa by SDS-PAGE. The enzyme was most active at a pH of 8.0 and temperature of 40°C and the enzyme was stable between a pH of 7 and 10 and up to a temperature of 50°C. The enzyme activity was enhanced by CaCl2 but was slightly inhibited by CoCl2 , MgSO4 , and AgNO3 . In addition, this enzyme was completely inhibited by phenylmethylsulfonyl fluoride, indicating that this enzyme was a serine protease. Furthermore, the alkaline protease was more stable in the presence of surfactants such as Triton X-100, which was followed by Tween 80 and SDS. Moreover, the enzyme was highly stable in the presence of 1% oxidizing agent (H2 O2 ). The enzyme also has significant stability (70%-80%) in a few organic solvents. Thus, the increased stability of the enzyme in the presence of oxidizing agent, surfactants, and organic solvents may find potential applications in the detergent industry and peptide synthesis in nonaqueous media.


Asunto(s)
Bacillus/química , Proteínas Bacterianas/aislamiento & purificación , Endopeptidasas/aislamiento & purificación , Tensoactivos/química , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Endopeptidasas/química , Endopeptidasas/metabolismo , Estabilidad de Enzimas , Calor , Concentración de Iones de Hidrógeno , Oxidantes
20.
Int J Biol Macromol ; 253(Pt 2): 126795, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37689304

RESUMEN

Dicranopteris linearis (DL) is a fern in the Gleicheniaceae family, locally known as resam by the Malay community. It has numerous pharmacological benefits, with antiulcer and gastroprotective properties. Peptic ulcer is a chronic and recurring disease that significantly impacts morbidity and mortality, affecting nearly 20 % of the world's population. Despite the effectiveness of peptic ulcer drugs, there is no perfect treatment for the ailment. Encapsulation is an advanced technique that can treat peptic ulcers by incorporating natural sources. This work aims to encapsulate DL extract using different types of cellulose particles by the solvent displacement technique for peptic ulcer medication. The extract was encapsulated using methyl cellulose (MC), ethyl cellulose (EC), and a blend of ethyl methyl cellulose through a dialysis cellulose membrane tube and freeze-dried to yield a suspension of the encapsulated DL extracts. The microencapsulated methyl cellulose chloroform extract (MCCH) has a considerably greater level of total phenolic (84.53 ± 6.44 mg GAE/g), total flavonoid (84.53 ± 0.54 mg GAE/g), and antioxidant activity (86.40 ± 0.63 %). MCCH has the highest percentage of antimicrobial activity against Escherichia coli (2.42 ± 107 × 0.70 CFU/mL), Bacillus subtilis (5.21 ± 107 × 0.90 CFU/mL), and Shigella flexneri (1.25 ± 107 × 0.66 CFU/mL), as well as the highest urease inhibitory activity (50.0 ± 0.21 %). The MCCH particle size was estimated to be 3.347 ± 0.078 µm in diameter. It has been proven that DL elements were successfully encapsulated in the methyl cellulose polymer in the presence of calcium (Ca). Fourier transform infrared (FTIR) analysis indicated significant results, where the peak belonging to the CO stretch of the carbonyl groups of methyl cellulose (MC) shifted from 1638.46 cm-1 in the spectrum of pure MC to 1639.10 cm-1 in the spectrum of the MCCH extract. The shift in the wavenumbers was due to the interactions between the phytochemicals in the chloroform extract and the MC matrix in the microcapsules. Dissolution studies in simulated gastric fluid (SGF) and model fitting of encapsulated chloroform extracts showed that MCCH has the highest EC50 of 6.73 ± 0.27 mg/mL with R2 = 0.971 fitted by the Korsmeyer-Peppas model, indicating diffusion as the mechanism of release.


Asunto(s)
Antiulcerosos , Úlcera Péptica , Humanos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Cloroformo , Diálisis Renal , Antiulcerosos/farmacología , Antiulcerosos/química , Celulosa/química , Metilcelulosa
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