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2.
Nature ; 565(7738): 230-233, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30602788

RESUMO

Yemen is currently experiencing, to our knowledge, the largest cholera epidemic in recent history. The first cases were declared in September 2016, and over 1.1 million cases and 2,300 deaths have since been reported1. Here we investigate the phylogenetic relationships, pathogenesis and determinants of antimicrobial resistance by sequencing the genomes of Vibrio cholerae isolates from the epidemic in Yemen and recent isolates from neighbouring regions. These 116 genomic sequences were placed within the phylogenetic context of a global collection of 1,087 isolates of the seventh pandemic V. cholerae serogroups O1 and O139 biotype El Tor2-4. We show that the isolates from Yemen that were collected during the two epidemiological waves of the epidemic1-the first between 28 September 2016 and 23 April 2017 (25,839 suspected cases) and the second beginning on 24 April 2017 (more than 1 million suspected cases)-are V. cholerae serotype Ogawa isolates from a single sublineage of the seventh pandemic V. cholerae O1 El Tor (7PET) lineage. Using genomic approaches, we link the epidemic in Yemen to global radiations of pandemic V. cholerae and show that this sublineage originated from South Asia and that it caused outbreaks in East Africa before appearing in Yemen. Furthermore, we show that the isolates from Yemen are susceptible to several antibiotics that are commonly used to treat cholera and to polymyxin B, resistance to which is used as a marker of the El Tor biotype.


Assuntos
Cólera/epidemiologia , Cólera/microbiologia , Genoma Bacteriano/genética , Genômica , Vibrio cholerae/genética , Vibrio cholerae/isolamento & purificação , Humanos , Filogenia , Vibrio cholerae/classificação , Iêmen/epidemiologia
3.
Environ Res ; 241: 117669, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37980993

RESUMO

The current work concentrates on the fabrication of Ga doped Co0.6Cu0.4Fe2O4 nanocatalysts via sol-gel auto-combustion (SGA) for the production of green and sustainable source of energy i.e., hydrogen through photocatalytic and electrocatalytic routes. Single-phased cubic crystal structure with Fd3m geometry was observed through XRD patterns. FESEM images show the aggregated and spherical shaped grains with distinct grain boundaries and average grain size of 1.04 and 1.39 µm for the Co0.6Cu0.4Fe2O4, and Co0.6Cu0.4Ga0.02Fe1.98O4 nanomaterials. Soft magnetic behaviour with a coercivity (Hc) and saturation magnetization (Ms) of 235.32-357.26 Oe and 54.65-61.11 emu/g was obtained for the produced nanomaterials. The estimation of photocatalytic nature for generating H2 was conducted using the sacrificial agents i.e., 0.128 M Na2S and 0.079 M Na2SO3. The analysis focused on measuring the maximum H2 generation was achieved by photocatalysts throughout three consecutive 4-h cycles. Out of all compositions, Co0.6Cu0.4Ga0.02Fe1.98O4 nanomaterial have the highest photocatalytic activity of 16.71 mmol gcat-1. However, the electrocatalytic behaviour of prepared Co0.6Cu0.4GaxFe2-xO4 (x = 0.00-0.03) electrocatalysts were determined for HER (Hydrogen evolution reaction) reaction. The overpotential values of Co0.6Cu0.4Fe2O4, Co0.6Cu0.4Ga0.01Fe1.99O4, Co0.6Cu0.4Ga0.02Fe1.98O4, and Co0.6Cu0.4Ga0.03Fe1.97O4 catalysts at 10 mA cm-2 were -0.81, -0.85, -1.03, and 1.21 V, correspondingly. Thus, at cathode current density of 10 mA/cm-2, an elevation in overpotential was noted, which indicates that the undoped Co0.6Cu0.4Fe2O4 (x = 0.00) electrocatalyst have remarkable electrocatalytic HER activity. Consequently, owing to photo/electro catalytic water splitting traits, the prepared catalysts are highly efficient for the green hydrogen generation.


Assuntos
Hidrogênio , Nanoestruturas , Catálise , Eletrodos , Fenótipo
4.
Opt Lett ; 48(14): 3753-3756, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37450742

RESUMO

The transfer function is the characteristic function of the dispersive element of a reconstructive spectrometer. It maps the transmitted spatial intensity profile to the incident spectral intensity profile of an input. Typically, a widely tunable and narrowband source is required to determine the transfer function across the entire operating wavelength range, which increases the developmental cost of these reconstructive spectrometers. In this Letter, we utilize the parabolic dispersion relation of a planar one-dimensional photonic crystal cavity, which acts as the dispersive element, to determine the entire transfer function of the spectrometer using measurements made at only two wavelengths. Using this approach, we demonstrate reliable reconstruction of input spectra in simulations, even in the presence of noise. The experimentally reconstructed spectra also follow the spectra measured using a commercial spectrometer.

5.
Med Microbiol Immunol ; 212(6): 407-419, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37787822

RESUMO

Mammalian cell entry (mce) operons play a vital role in cell invasion and survival of M. tuberculosis. Of the mce genes, the function of Rv0590A is still unknown. The present study was performed to investigate the function and immunogenic properties of the protein Rv0590A. Human leukemia monocytic cell line (THP-1) derived macrophages were infected with M. tuberculosis H37Rv at 3, 6, and 24 h of infection. The maximum colony forming units (CFU) were observed at 6 h (p < 0.005), followed by 3 h after infection. M. tuberculosis H37Rv and clinical isolates representative of Delhi/CAS, EAI, Beijing, Haarlem and Euro-American-superlineage were included in the study for expression analysis of mce1A, mce2A, mce3A, mce4A, and Rv0590A genes. Maximum upregulation of all mce genes was observed at 3 h of infection. All the five clinical isolates and H37Rv upregulated Rv0590A at various time points. Macrophage infection with M. tuberculosis H37Rv-overexpressing Rv0590A gene showed higher intracellular CFU as compared to that of wild-type H37Rv. Further, purified Rv0590A protein stimulated the production of TNFα, IFNγ, and IL-10 in macrophages. Thus, Rv0590A was found to be involved in cell invasion and showed good immunological response.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Animais , Humanos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Internalização do Vírus , Mycobacterium tuberculosis/genética , Antígenos de Bactérias/genética , Mamíferos
6.
Environ Res ; 231(Pt 1): 116103, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37178745

RESUMO

Copper and dysprosium doped NiFe2O4 magnetic nanomaterials, Ni1-xCuxDyyFe2-yO4 (x = y = 0.00, 0.01, 0.02, 0.03), was prepared by utilizing sol-gel auto-combustion approach to inspect the photodegradation of methylene blue (MB) pollutant and also, to perform the electrocatalytic water splitting and antibacterial studies. The XRD analysis reveal the growth of a single-phase spinel cubic structure for produced nanomaterials. The magnetic traits show an increasing trend in saturation magnetization (Ms) from 40.71 to 47.90 emu/g along with a decreasing behaviour of coercivity from 158.09 to 156.34 Oe at lower and higher Cu and Dy doping content (x = 0.0-0.01). The study of optical band gap values of copper and dysprosium-doped nickel nanomaterials decreased from 1.71 to 1.52 eV. This will increase the photocatalytic degradation of methylene blue pollutant from 88.57% to 93.67% under natural sunlight, respectively. These findings clearly show that under natural sunlight irradiation for 60 min, the produced N4 photocatalyst displays the greatest photocatalytic activity with a maximum removal percentage of 93.67%. The electrocatalytic characteristics of produced magnetic nanomaterials for both HER and OER were examined with a Calomel electrode taking as a reference in a 0.5 N H2SO4 and 0.1 N KOH electrolyte. The N4 electrode demonstrated considerable 10 and 0.024 mA/cm2 of current density, with onset potentials of 0.99 and 1.5 V for HER and OER and also, have tafel slopes of 58.04 and 295 mV/dec, respectively. The antibacterial activity for produced magnetic nanomaterials was examined against various bacteria (Bacillus subtilis, Staphylococcus aureus, S. typhi, and P. aeruginosa) in which N3 sample produced significant inhibition zone against gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) but no zone of inhibition against gram-negative bacteria (S. typhi and P. aeruginosa). With all these superior traits, the produced magnetic nanomaterials are highly valuable for the wastewater remediation, hydrogen evolution, and biological applications.


Assuntos
Cobre , Nanopartículas de Magnetita , Azul de Metileno/química , Disprósio , Antibacterianos/farmacologia , Antibacterianos/química
7.
Proc Natl Acad Sci U S A ; 116(13): 6226-6231, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30867296

RESUMO

The Bay of Bengal is known as the epicenter for seeding several devastating cholera outbreaks across the globe. Vibrio cholerae, the etiological agent of cholera, has extraordinary competency to acquire exogenous DNA by horizontal gene transfer (HGT) and adapt them into its genome for structuring metabolic processes, developing drug resistance, and colonizing the human intestine. Antimicrobial resistance (AMR) in V. cholerae has become a global concern. However, little is known about the identity of the resistance traits, source of AMR genes, acquisition process, and stability of the genetic elements linked with resistance genes in V. cholerae Here we present details of AMR profiles of 443 V. cholerae strains isolated from the stool samples of diarrheal patients from two regions of India. We sequenced the whole genome of multidrug-resistant (MDR) and extensively drug-resistant (XDR) V. cholerae to identify AMR genes and genomic elements that harbor the resistance traits. Our genomic findings were further confirmed by proteome analysis. We also engineered the genome of V. cholerae to monitor the importance of the autonomously replicating plasmid and core genome in the resistance profile. Our findings provided insights into the genomes of recent cholera isolates and identified several acquired traits including plasmids, transposons, integrative conjugative elements (ICEs), pathogenicity islands (PIs), prophages, and gene cassettes that confer fitness to the pathogen. The knowledge generated from this study would help in better understanding of V. cholerae evolution and management of cholera disease by providing clinical guidance on preferred treatment regimens.


Assuntos
Cólera/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Transferência Genética Horizontal , Genoma Bacteriano/genética , Vibrio cholerae/genética , Antibacterianos/farmacologia , Conjugação Genética/genética , Elementos de DNA Transponíveis/genética , Diarreia/microbiologia , Evolução Molecular , Fezes/microbiologia , Variação Genética , Ilhas Genômicas/genética , Humanos , Imipenem/farmacologia , Índia , Sequências Repetitivas Dispersas/genética , Fenótipo , Plasmídeos/genética , Prófagos/genética , Proteoma , Vibrio cholerae/efeitos dos fármacos , Vibrio cholerae/isolamento & purificação , Vibrio cholerae/patogenicidade , Vibrio cholerae O1/genética , Vibrio cholerae O1/isolamento & purificação , Vibrio cholerae O1/patogenicidade , Sequenciamento Completo do Genoma
8.
Opt Express ; 29(17): 26645-26657, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34615095

RESUMO

Optical spectrometers have propelled scientific and technological advancements in a wide range of fields. While sophisticated systems with excellent performance metrics are serving well in controlled laboratory environments, many applications require systems that are portable, economical, and robust to optical misalignment. Here, we propose and demonstrate a spectrometer that uses a planar one-dimensional photonic crystal cavity as a dispersive element and a reconstructive computational algorithm to extract spectral information from spatial patterns. The simple fabrication and planar architecture of the photonic crystal cavity render our spectrometry platform economical and robust to optical misalignment. The reconstructive algorithm allows miniaturization and portability. The intensity transmitted by the photonic crystal cavity has a wavelength-dependent spatial profile. We generate the spatial transmittance function of the system using finite-difference time-domain method and also estimate the dispersion relation. The transmittance function serves as a transfer function in our reconstructive algorithm. We show accurate estimation of various kinds of input spectra. We also show that the spectral resolution of the system depends on the cavity linewidth that can be improved by increasing the number of periodic layers in distributed Bragg mirrors. Finally, we experimentally estimate the center wavelength and linewidth of the spectrum of an unknown light emitting diode. The estimated values are in good agreement with the values measured using a commercial spectrometer.

9.
Am J Dent ; 33(5): 258-264, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33017529

RESUMO

PURPOSE: To compare the effectiveness in reducing plaque and gingivitis of a fluoride toothpaste with 20% baking soda and a fluoride toothpaste control. METHODS: 159 subjects, who met the entry criteria, participated in this single-center, double-blind, randomized, parallel-group clinical study. Gingival Index (MGI), Gingival Bleeding Index (GBI), and Plaque Index (PI) were assessed after 4, 8, and 12 weeks use of the assigned test or control toothpaste. After 12 weeks, participants resumed 4 weeks of their customary oral hygiene after which they were re-evaluated using the same measures. RESULTS: Both toothpastes statistically significantly reduced MGI, GBI, and PI versus baseline at all-time points. Brushing with the 20% baking soda toothpaste statistically significantly reduced MGI, PI, and GBI compared to the control toothpaste at all time points. After 12 weeks, the reductions in MGI, PI, and GBI were 12.6%, 9.6%, and 44.2%, respectively. After the 4-week customary oral hygiene period, the benefits of the study period had begun to diminish, but statistically significant reductions in MGI and GBI for the test versus control were still evident. This 3-month clinical study shows that brushing with fluoride toothpaste containing 20% baking soda reduces dental plaque and concurrently reduces gingival inflammation and bleeding compared to toothpaste with fluoride alone. CLINICAL SIGNIFICANCE: Fluoride toothpaste with 20% baking soda has the potential to offer multiple oral health benefits when used as an adjunct to regular tooth brushing and, therefore, may be confidently recommended to patients.


Assuntos
Placa Dentária/prevenção & controle , Gengivite/prevenção & controle , Índice de Placa Dentária , Humanos , Bicarbonato de Sódio/uso terapêutico , Cremes Dentais/uso terapêutico
10.
J Clin Pediatr Dent ; 40(1): 76-80, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26696111

RESUMO

Mandibular fractures are one of the most common maxillofacial traumatic injuries. They are also reported to be associated with highest rate of post-operative infection. In mixed dentition, management of tooth buds in line of fracture present great challenge to the surgeon. Timely management and non-invasive techniques can help in alleviating complications associated with fractures in children. Such cases should be kept on long-term follow-up for evaluation of proper growth and development. This case report documents a child having a history of previous mandibular fracture and extra-oral sinus tract associated with infected dental follicle.


Assuntos
Fístula Dentária/etiologia , Saco Dentário/lesões , Fraturas Mandibulares/complicações , Criança , Fístula Dentária/microbiologia , Feminino , Seguimentos , Humanos , Supuração , Germe de Dente/lesões
11.
Curr Top Microbiol Immunol ; 379: 49-85, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24831345

RESUMO

Cholera is a global health problem as several thousands of cases and deaths occur each year. The unique epidemiologic attribute of the disease is its propensity to occur as outbreaks that may flare-up into epidemics, if not controlled. The causative bacterial pathogen Vibrio cholerae prevails in the environment and infects humans whenever there is a breakdown in the public health component. The Indian subcontinent is vulnerable to this disease due its vast coastlines with areas of poor sanitation, unsafe drinking water, and overcrowding. Recently, it was shown that climatic conditions also play a major role in the persistence and spread of cholera. Constant change in the biotypes and serotypes of V. cholerae are also important aspects that changes virulence and survival of the pathogen. Such continuous changes increase the infection ability of the pathogen affecting the susceptible population including the children. The short-term carrier status of V. cholerae has been studied well at community level and this facet significantly contributes to the recurrence of cholera. Several molecular tools recognized altering clonality of V. cholerae in relation with the advent of a serogroup or serotype. Rapid identification systems were formulated for the timely detection of the pathogen so as to identify and control the outbreak and institute proper treatment of the patients. The antimicrobials used in the past are no longer useful in the treatment of cholera as V. cholerae has acquired several mechanisms for multiple antimicrobial resistance. This upsurge in antimicrobial resistance directly influences the management of the disease. This chapter provides an overview of cholera prevalence in India, possible sources of infection, and molecular epidemiology along with antimicrobial resistance of V. cholerae.


Assuntos
Cólera/epidemiologia , Surtos de Doenças , Cólera/tratamento farmacológico , Cólera/microbiologia , Farmacorresistência Bacteriana , Humanos , Incidência , Índia/epidemiologia , Epidemiologia Molecular , Estações do Ano
12.
Arch Virol ; 160(5): 1219-28, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25772572

RESUMO

Cotton leaf curl disease (CLCuD) is a serious disease of cotton on the Indian subcontinent. In the present study, three cotton leaf curl viruses, cotton leaf curl Burewala virus (CLCuBuV), cotton leaf curl Kokhran virus (CLCuKoV) and cotton leaf curl Multan virus (CLCuMV), and their associated satellites, cotton leaf curl Multan betasatellite (CLCuMB) and cotton leaf curl Multan alphasatellite (CLCuMA), were detected. CLCuBuV with either intact (CLCuBuV-1) or mutant (CLCuBuV-2) transcriptional activator protein (TrAP) were detected in different plants. Agroinoculation with CLCuBuV-1 or CLCuBuV-2 together with CLCuMB and CLCuMA, resulted in typical leaf curling and stunting of tobacco plants. Inoculation with CLCuKoV or an isolate of CLCuMV (CLCuMV-2), together with CLCuMB and CLCuMA, induced severe leaf curling, while the other isolate of CLCuMV (CLCuMV-1), which was recombinant in origin, showed mild leaf curling in tobacco. To investigate the effect of intact or mutant TrAP and also the recombination events, CLCuBuV-1, CLCuBuV-2, CLCuMV-1 or CLCuMV-2 together with the satellites (CLCuMA and CLCuMB) were transferred to cotton via whitefly-mediated transmission. Cotton plants containing CLCuBuV-1, CLCuBuV-2 or CLCuMV-2 together with satellites showed curling and stunting, whereas the plants having CLCuMV-1 and the satellites showed only mild and indistinguishable symptoms. CLCuBuV-1 (intact TrAP) showed severe symptoms in comparison to CLCuBuV-2 (mutant TrAP). The present study reveals that two types of CLCuBuV, one with an intact TrAP and the other with a mutant TrAP, exist in natural infection of cotton in India. Additionally, CLCuMuV-1, which has a recombinant origin, induces mild symptoms in comparison to the other CLCuMV isolates.


Assuntos
Begomovirus/isolamento & purificação , DNA Satélite/isolamento & purificação , Gossypium/virologia , Doenças das Plantas/virologia , Transativadores/metabolismo , Begomovirus/classificação , Begomovirus/genética , Begomovirus/fisiologia , Análise por Conglomerados , DNA Satélite/classificação , DNA Satélite/fisiologia , DNA Viral/química , DNA Viral/genética , Índia , Dados de Sequência Molecular , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Filogenia , Proteínas , Análise de Sequência de DNA , Homologia de Sequência , Nicotiana/virologia , Transativadores/genética , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
13.
J Oral Maxillofac Surg ; 73(12): 2379.e1-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26428614

RESUMO

PURPOSE: This study aimed to quantify articular soft tissue injury in condylar fractures based on magnetic resonance imaging (MRI) findings and investigate the impact of severity of articular soft tissue injury on the development of postoperative complications after functional reduction of a condylar fracture. PATIENTS AND METHODS: Fifty-four patients 18 to 60 years old with unilateral undisplaced, deviated, or displaced condylar fractures were included in this prospective study. Articular soft tissue within the temporomandibular joint (TMJ) was evaluated using MRI within 7 days after the condylar fracture. Based on MRI findings, such injuries were classified as grade I (hemarthrosis only), grade II (hemarthrosis and disc displacement), grade III (hemarthrosis, disc displacement, and capsular tear), or grade IV (disc perforation in association with grade I, II, or III). All condylar fractures were treated conservatively using a standardized functional reduction method and patients were followed for 1 year. RESULTS: In 37 of 54 TMJs, MRI diagnosis of disc displacement was established, and capsular tear was observed in 12 joints and hemarthrosis was present in 42 joints. Disc perforation was present in only 5 cases. Patients with hemarthrosis alone (grade I) had the best outcome after functional reduction, whereas patients with hemarthrosis and disc displacement (grade II) had comparatively poorer results. Fifty percent of patients with grade II injury and 66.6% of patients with associated capsular tear (grade III) had limited mouth opening and restricted movement at the end of the follow-up period. One hundred percent of patients with disc perforation (grade IV) had restricted joint movement and joint noise. CONCLUSION: Results suggest that serious injury to the articular disc and capsule of the TMJ is a major contributing factor toward the development of complications after closed reduction of a condylar fracture.


Assuntos
Côndilo Mandibular/lesões , Fraturas Mandibulares/diagnóstico , Articulação Temporomandibular/lesões , Adolescente , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Côndilo Mandibular/patologia , Fraturas Mandibulares/patologia , Fraturas Mandibulares/terapia , Pessoa de Meia-Idade , Estudos Prospectivos , Lesões dos Tecidos Moles/diagnóstico , Lesões dos Tecidos Moles/patologia , Lesões dos Tecidos Moles/terapia , Articulação Temporomandibular/patologia , Índices de Gravidade do Trauma , Resultado do Tratamento , Adulto Jovem
14.
Am J Dent ; 27(2): 106-10, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25000669

RESUMO

PURPOSE: To assess the dentin hypersensitivity-reducing effectiveness of a 0.454% stannous-containing dentifrice as compared to a marketed negative control dentifrice after the first brushing as well as after 3 days and 2 weeks of twice daily use. METHODS: This was a 2-week, randomized, double-blind, parallel group, single-center clinical investigation in confirmed dentin hypersensitivity adult sufferers. At baseline, subjects were stratified by age, gender, and thermal sensitivity scores, and randomly assigned to a marketed 0.454% stannous fluoride (SnF2) dentifrice or a marketed sodium fluoride (NaF) dentifrice negative control. Following baseline assessment of tactile and thermal sensitivity via the Yeaple Probe and air-blast/Schiff Air Index evaluations, respectively, subjects brushed once on-site with their assigned test product following the same usage instructions. Post-brushing tactile and thermal sensitivity were then assessed ('Immediate' evaluation). Subjects subsequently brushed twice daily at home for a 2-week period, with the same tactile and thermal efficacy evaluations repeated at Day 3 and Week 2 post-baseline. RESULTS: All 116 enrolled subjects completed all evaluations. The stannous fluoride dentifrice provided significantly (P < 0.0001) superior dentin hypersensitivity reduction compared to the negative control dentifrice at each time point and by both evaluation measures: superior mean relative Yeaple Probe (tactile) benefits were 124.5% after one use, 203.8% after 3 days, and 222.5% after 2 weeks; and superior mean relative Schiff Air Index (thermal) benefits were 27.6% after a single use, 44.6% at Day 3, and 74.2% at Week 2. Both dentifrices were well-tolerated.


Assuntos
Dentifrícios/uso terapêutico , Dessensibilizantes Dentinários/uso terapêutico , Sensibilidade da Dentina/tratamento farmacológico , Fluoretos de Estanho/uso terapêutico , Adulto , Idoso , Ar , Temperatura Baixa , Sensibilidade da Dentina/classificação , Método Duplo-Cego , Feminino , Fluoretos/uso terapêutico , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fosfatos/uso terapêutico , Escovação Dentária/métodos , Tato , Adulto Jovem
15.
Prep Biochem Biotechnol ; 44(3): 281-90, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24274016

RESUMO

Guava juice is known to be rich in antioxidant activity due a high level of vitamins A and C. However, tannins present in the guava juice form tannin-protein complexes that affect the utilization of vitamins and minerals and inhibit digestive enzymes. Beside this, bitterness and cloudiness are the other major problems of juice industries. The present study aimed to utilize a low-cost substrate (tea residue) for the production of tannase and its application in detannification of guava juice. Solid-state fermentation (SSF) was evaluated to produce tannase from Aspergillus niger. Maximum tannase (1.86 U/g dry substrate) production was observed at 30°C after 96 hr of the incubation period. The optimum pH of the moistening agent was found to be 5.0. Partially purified enzyme using ammonium sulfate precipitation was subjected to guava juice treatment at a level of 0.5, 1.0, and 2.0% for 30 and 60 min. Decrease in tannic acid content of guava juice was found to be 17.60, 29.04, and 44.38% after 30 min and 40.59, 53.69, and 59.23% after 60 min, respectively.


Assuntos
Aspergillus niger/enzimologia , Bebidas/análise , Hidrolases de Éster Carboxílico/metabolismo , Fermentação , Psidium/química , Taninos/química , Aspergillus niger/metabolismo , Microbiologia Industrial , Psidium/metabolismo , Taninos/metabolismo
16.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 9): o955-6, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25309277

RESUMO

The title Schiff base compound, C28H21Cl2N3O, was synthesized by the condensation of 1-(3,4-di-chloro-phen-yl)-3-methyl-4-(4-methyl-benzo-yl)-1H-pyrazol-5(4H)-one with 1-aminona-phthalene. The p-tolyl ring is normal to the pyrazole ring, with a dihedral angle of 88.02 (14)°, and inclined to the naphthalene ring system by 78.60 (12)°. The pyrazole ring is inclined to the naphthalene ring system and the di-chloro-substituted benzene ring by 63.30 (12) and 11.03 (13)°, respectively. The amino group and carbonyl oxygen atom are involved in an intra-molecular N-H⋯O hydrogen bond enclosing an S(6) ring motif. There is also a short C-H⋯O contact involving the carbonyl O atom and the adjacent benzene ring. In the crystal, mol-ecules are linked by C-H⋯π inter-actions, forming a three-dimensional structure.

17.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 10): o1098-9, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25484692

RESUMO

In the title mol-ecule, C19H21FN6O4, the dihedral angles between the benzene ring and essentially planar pyrimidine rings [maximum deviations of 0.036 (2) and 0.056 (2) Å] are 73.32 (7) and 63.81 (8)°. The dihedral angle between the mean planes of the pyrimidine rings is 61.43 (6)°. In the crystal, N-H⋯O hydrogen bonds link mol-ecules, forming a two-dimensional network parallel to (001) and in combination with weak C-H⋯O hydrogen bonds, a three-dimensional network is formed. Weak C-H⋯π inter-actions and π-π inter-actions, with a centroid-centroid distance of 3.599 (2) Šare also observed.

18.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 10): o1136-7, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25484715

RESUMO

The title compound, C18H14Cl2N2O2, crystallizes with two mol-ecules, A and B, in the asymmetric unit. In mol-ecule A, the dihedral angles between the central pyrazole ring and pendant di-chloro-benzene and p-tolyl rings are 2.18 (16) and 46.78 (16)°, respectively. In mol-ecule B, the equivalent angles are 27.45 (16) and 40.45 (18)°, respectively. Each mol-ecule features an intra-molecular O-H⋯O hydrogen bond, which closes an S(6) ring and mol-ecule A also features a C-H⋯O inter-action. In the crystal, weak C-H⋯π interactions and aromatic π-π stacking [shortest centroid-centroid separation = 3.707 (2) Å] generate a three-dimensional network.

19.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 7): o795-6, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25161577

RESUMO

In the asymmetric unit of the title compound, C16H14N4O3·C2H6OS, there are two independent main mol-ecules (A and B) and two dimethyl sulfoxide solvent mol-ecules. In mol-ecule A, the pyran ring is in a flattened sofa conformation, with the sp (3)-hydridized C atom forming the flap. In mol-ecule B, the pyran ring is in a flattened boat conformation, with the sp (3)-hydridized C atom and the O atom deviating by 0.073 (3) and 0.055 (3) Å, respectively, from the plane of the other four atoms. The mean planes the pyrazole and phenyl rings form dihedral angles of 84.4 (2) and 84.9 (2)°, respectively, for mol-ecules A and B. In the crystal, N-H⋯O and N-H⋯N hydrogen bonds link the components of the structure into chains along [010]. In both solvent mol-ecules, the S atoms are disordered over two sites, with occupancy ratios of 0.679 (4):0.321 (4) and 0.546 (6):0.454 (6).

20.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 8): o875-6, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25249920

RESUMO

In the title compound, C17H18N4O4, the dihedral angle between the benzene ring and 2,4-di-hydro-pyrano[2,3-c]pyrazole ring system is 89.41 (7)°. The pyran moiety adopts a strongly flattened boat conformation. In the crystal, mol-ecules are linked by N-H⋯N, N-H⋯O, C-H⋯N and C-H⋯O hydrogen bonds into an infinite two-dimensional network parallel to (110). There are π-π inter-actions between the pyrazole rings in neighbouring layers [centroid-centroid distance = 3.621 (1) Å].

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