Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
1.
Med J Armed Forces India ; 80(3): 276-280, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38799995

RESUMEN

Background: Dengue is one of the most important vector-borne disease in India. It has been linked to monsoons when Aedes aegypti mosquitoes breed profusely in containers. No study exists in Armed Forces wherein a community-based sero-survey has described the epidemiology of dengue. The present study tries to fill this knowledge gap. Methods: A total of 422 participants were studied for one transmission season of July-December. Blood samples were collected for testing dengue IgG and IgM at the beginning and at end of the study period. The study participants were interviewed at least twice within this period of 6 months to assess clinical condition and follow-up. Point prevalence and incidence were measured. Distribution of presence or absence of symptoms was noted for positive as well as negative cases. Results: All participants were males. Average age was 31.75 years. Point prevalence at the beginning of transmission season was 11.6% (95% CI: 8.4%-14.6%) and 15.6% (95% CI: 12.1%-19.1%) towards the end. Incidence was found to be 147.4 per 1000 for 6 months. Forty percent of incident cases were asymptomatic. Conclusion: Healthcare planners and hospital commanders in stations across Armed Forces can use the prevalence and incidence figures obtained in this study as a general guide while planning for prevention and control of dengue. Also, this study points to the fact that dengue transmission in Delhi may have shifted earlier to months of April/May than the conventionally accepted season of July-December.

2.
ChemSusChem ; : e202400381, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38801175

RESUMEN

A widely used method to obtain tetrazoles is through the azide and nitrile [3+2] cycloaddition. However, this process often involves using non-recyclable transition metals or Lewis acid catalysts and stoichiometric amounts of oxidants and additives, which reduces atom efficiency. We have discovered a convergent paired electrochemical reaction to perform this cycloaddition reaction, without the need for metal catalysts or oxidants. This tetrazolation strategy uses azidotrimethylsilane (TMSN3) and N-heterocycles in an undivided cell at a constant current. We use a mixture of CH3CN and equivalent amounts of H2O as co-solvent at room temperature. It is crucial to produce a stoichiometric amount of active hydroxyl ions through the cathodic reduction of water. Cyclic voltammetry (CV) studies and control experiments confirm that the cycloaddition reaction is specific to the electrode electron transfer process, eliminating the need for a mediator to shuttle electrons. This metal- and oxidant-free strategy is highly compatible with different functional groups and produces products with moderate to good yields. We have successfully tetrazolated bioactive compounds at a late stage, scaled up batches efficiently, and synthesized free amino-containing N-heterocycles via denitrogenation of tetrazoles.

3.
J Orthop Case Rep ; 14(1): 137-140, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38292098

RESUMEN

Introduction: C1-2 rotatory subluxation is more commonly seen in children compared to in adults. It often has a history of respiratory tract infection, cervical trauma, and recent history of surgery of the head or neck. Case Report: A 6-year-old boy presented to us with complaints of insidious onset of progressive deformity of the neck since the past 3 months. On examination, the patient had a classic "cock robin" deformity with his left head tilt and right-sided chin rotation. There was tenderness and spasm of the left sternocleidomastoid muscle. Radiologically, the child had unilateral C1-C2 facetal dislocation. There were associated abnormalities consisting of unilateral occiputoatlantal fusion and C2-C3 fusion. Magnetic resonance imaging (MRI) showed C1-C2 subluxation with kyphotic deformity the apex of which was impinging on the brainstem. The patient was put on skull traction with Crutchfield Tongs with progressively increasing weights for 1 week and serial X-rays were taken. Computed tomography (CT) scan was repeated at the end of 1 week which showed no improvement. C1-C2 open reduction and fusion was done. Post-operative period was uneventful. He improved on serial follow-ups. At follow-up at 18 months, the child remains comfortable, is going to school and doing all indoor and outdoor activities. His posture continues to be balanced. Radiologically, C1-C2 joint shows signs of a solid fusion. Conclusion: A thorough history taking and a meticulous clinical examination if important for evaluation of torticollis in a child. Proper imaging helps in confirming the diagnosis and grading the severity. Prompt treatment is necessary for getting a good outcome.

4.
Biosens Bioelectron ; 246: 115902, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38056339

RESUMEN

Extracellular protein kinase A autoantibody (ECPKA-AutoAb) has been suggested as a universal cancer biomarker due to its higher amounts in serum of several types of cancer patients than that of normal individuals. Herein, we first developed a lateral flow immunoassay (LFIA) tool, using a sandwich format, toward ECPKA-AutoAb in human serum. For this format, 3G2 as a capture antibody was identified using hybridoma technique and a series of screenings where it showed superior capacity to recognize Enzo PKA catalytic subunit alpha (Cα), compared to other PKA antibodies and antigens. Using these components, we performed sandwich ELISA toward a mimic and real sample of ECPKA-AutoAb. As per the results, limit of detection (LOD) was found to be 135 ng/mL and ECPKA-AutoAb levels were higher in various cancer patients than in normal individuals like previous studies. Based on these results, we applied this sandwich format into LFIA tool and found that the LOD of the fabricated LFIA tool showed about 3.8 ng/mL using spiked PKA-Ab, which is significantly improved compared to the LOD of sandwich ELISA. Also, the developed LFIA tool demonstrated a remarkable ability to detect significant differences in ECPKA-AutoAb levels between normal and cancer patients within 15 min, showing a potential for point-of-care (PoC) detection. One interesting point is that our LFIA strip contains an additional conjugation pad II, named because of its position behind the conjugation pad, in which PKA Cα is dried, enabling a sandwich format.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Neoplasias , Humanos , Autoanticuerpos , Proteínas Quinasas , Neoplasias/diagnóstico , Inmunoensayo/métodos , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Límite de Detección , Pruebas Serológicas
5.
Chemistry ; 30(6): e202303118, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-37934155

RESUMEN

An electrooxidative C-H functionalization is a widely accepted route to obtain sulfur-containing arenes and heteroarenes. However, this process often involves using non-recyclable supporting electrolytes, (co)solvents like hexafluoroisopropanol, additives like acid, or catalysts. The use of additional reagents can increase costs and waste, reducing atom efficiency. Moreover, unlike other nitrogen-containing heterocycles, there have only been sporadic reports of electrochemical C-H functionalization in fused pyrimidin-4-ones, and an electrolyte-free process has yet to be developed. This work demonstrates that such anodic coupling reactions can be performed in an all-green electrolytic system without using such additional electrolytes or HFIP, maintaining a high atom economy. This C-H functionalization strategy utilizes inexpensive sodium sulfinates and ammonium thiocyanate as sulfonylating and thiocyanating agents in an undivided cell at a constant current, using a mixture of CH3 CN/H2 O as solvent at room temperature. Thus, fused pyrimidin-4-ones can be selectively converted into C3-sulfonylated and -thiocyanated derivatives in moderate to good yields.

6.
Food Chem ; 428: 136796, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37441937

RESUMEN

In this study, water-soluble carbon dots (CDs) were employed as a novel fluorescence "turn OFF-ON" sensor to detect Fe3+ ions in pharmaceutical sample and propiconazole (PC) in food samples. Blue fluorescent "LPCDs" are synthesized from the lemon peel that exhibited emission at 468 nm when excited at 378 nm. The average size of the as-prepared LPCDs is 2.03 nm, displaying a quantum yield of 32 %. Fluorescence "turn OFF-ON" strategy was developed for sensing of Fe3+ ion and PC, demonstrating favorable linearity in the range of 0.5-180 µM and 0.1-40 µM with the detection limits of 0.18 µM and 0.054 µM for Fe3+ and PC, respectively. Further, LPCDs-loaded cellulose paper was used as visual reader to detect Fe3+ and PC. This approach was effectively applied to detect Fe3+ and PC in pharmaceutical and vegetable samples.


Asunto(s)
Plaguicidas , Puntos Cuánticos , Fluorescencia , Carbono , Preparaciones Farmacéuticas , Colorantes Fluorescentes , Espectrometría de Fluorescencia
7.
Environ Res ; 232: 116318, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37302744

RESUMEN

In this work, we have synthesized four different color (yellow, orange, green, and blue (multicolor)) silver nanostructures (AgNSs) by chemical reduction method where silver nitrate, sodium borohydride and hydrogen peroxide were used as reagents. The as-synthesized multicolor AgNSs were successfully functionalized with bovine serum albumin (BSA) and applied as a colorimetric sensor for the assaying of metal cations (Cr3+, Hg2+, and K+). The addition of metal ions (Cr3+, Hg2+, and K+) into BSA functionalized AgNSs (BSA-AgNSs) causes the aggregation of BSA-AgNSs, and are accompanied by visual color changes with red or blue shift in the surface plasmon resonance (SPR) band of BSA-AgNSs. The BSA-AgNSs show different SPR characteristic for each metal ions (Cr3+, Hg2+, and K+) with exhibiting different spectral shift and color change. The yellow color BSA-AgNSs (Y-BSA-AgNSs) act as a probe for sensing Cr3+, orange color BSA-AgNSs (O-BSA-AgNSs) act as probe for Hg2+ ion assay, green color BSA-AgNSs (G-BSA-AgNSs) act as a probe for the assaying of both K+ and Hg2+, and blue color BSA-AgNSs (B-BSA-AgNSs) act as a sensor for colorimetric detection of K+ ion. The detection limits were found to be 0.26 µM for Cr3+ (Y-BSA-AgNSs), 0.14 µM for Hg2+ (O-BSA-AgNSs), 0.05 µM for K+ (G-BSA-AgNSs), 0.17 µM for Hg2+ (G-BSA-AgNSs), and 0.08 µM for K+ (B-BSA-AgNSs), respectively. Furthermore, multicolor BSA-AgNSs were also applied for assaying of Cr3+, and Hg2+ in industrial water samples and K+ in urine sample.


Asunto(s)
Mercurio , Nanopartículas del Metal , Nanoestructuras , Colorimetría/métodos , Agua/química , Nanopartículas del Metal/química , Cationes
8.
ACS Appl Bio Mater ; 6(4): 1621-1628, 2023 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-36972355

RESUMEN

The lethality of the bovine viral diarrhea virus (BVDV) in cattle involves inapparent infection and various, typically subclinical, syndromes. Cattle of all ages are vulnerable to infection with the virus. It also causes considerable economic losses, primarily due to reduced reproductive performance. In the absence of treatment that can completely cure infected animals, detection of BVDV relies on highly sensitive and selective diagnosis methods. In this study, an electrochemical detection system was developed as a useful and sensitive system for the detection of BVDV to suggest the direction of diagnostic technology through the development of conductive nanoparticle synthesis. As a countermeasure, a more sensitive and rapid BVDV detection system was developed using the synthesis of electroconductive nanomaterials black phosphorus (BP) and gold nanoparticle (AuNP). To increase the conductivity effect, AuNP was synthesized on the BP surface, and the stability of BP was improved by using dopamine self-polymerization. Moreover, its characterizations, electrical conductivity, selectivity, and sensitivity toward BVDV also have been investigated. The BP@AuNP-peptide-based BVDV electrochemical sensor exhibited a low detection limit of 0.59 copies mL-1 with high selectivity and long-term stability (retaining 95% of its initial performance over 30 days).


Asunto(s)
Diarrea Mucosa Bovina Viral , Virus de la Diarrea Viral Bovina , Nanopartículas del Metal , Animales , Bovinos , Oro , Diarrea Mucosa Bovina Viral/diagnóstico , Péptidos
9.
Chemistry ; 29(31): e202300421, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-36892524

RESUMEN

The regioselective E→Z isomerization of a target olefin unit embedded in a conjugated polyene is challenging. Examples are limited to retinal and its derivatives only. The problem is further amplified when such an isomerization is integrated into cascade sequences, among which the regioselectivity and subsequent directionality are the major bottlenecks. Indeed, there are no reports till date for such a transformation. Herein, it is reported that such a controlled isomerization and subsequent cyclization cascade can be enabled by photosensitizer-free direct irradiation of linearly conjugated acyclic polyenes in dichloromethane solvent using a 390 nm LED. The directionality results from deconjugation of the extended π-system in the transient Z-isomer due to stabilizing n→π* interactions between 1,4-dicarbonyls (C=O→C=O) or 1,4-carbonyl/-aryl (C=O→aryl) groups. The involvement of such noncovalent interactions has been supported by X-ray crystallography and control experiments. Thus, conjugated trienones can be stereoselectively converted into oxabicyclo[3.2.1]octadienes in an atom- and step-economic manner, including the first example by regioselective isomerization of a tetrasubstituted alkene. The reaction conditions are very general (>46 examples). The reaction can be conducted under open air atmosphere at ambient temperature. Such a cascade cyclization can also be realized in solid state.

10.
Leukemia ; 37(4): 751-764, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36720973

RESUMEN

Acute myeloid leukemia (AML) is a heterogeneous, aggressive malignancy with dismal prognosis and with limited availability of targeted therapies. Epigenetic deregulation contributes to AML pathogenesis. KDM6 proteins are histone-3-lysine-27-demethylases that play context-dependent roles in AML. We inform that KDM6-demethylase function critically regulates DNA-damage-repair-(DDR) gene expression in AML. Mechanistically, KDM6 expression is regulated by genotoxic stress, with deficiency of KDM6A-(UTX) and KDM6B-(JMJD3) impairing DDR transcriptional activation and compromising repair potential. Acquired KDM6A loss-of-function mutations are implicated in chemoresistance, although a significant percentage of relapsed-AML has upregulated KDM6A. Olaparib treatment reduced engraftment of KDM6A-mutant-AML-patient-derived xenografts, highlighting synthetic lethality using Poly-(ADP-ribose)-polymerase-(PARP)-inhibition. Crucially, a higher KDM6A expression is correlated with venetoclax tolerance. Loss of KDM6A increased mitochondrial activity, BCL2 expression, and sensitized AML cells to venetoclax. Additionally, BCL2A1 associates with venetoclax resistance, and KDM6A loss was accompanied with a downregulated BCL2A1. Corroborating these results, dual targeting of PARP and BCL2 was superior to PARP or BCL2 inhibitor monotherapy in inducing AML apoptosis, and primary AML cells carrying KDM6A-domain mutations were even more sensitive to the combination. Together, our study illustrates a mechanistic rationale in support of a novel combination therapy for AML based on subtype-heterogeneity, and establishes KDM6A as a molecular regulator for determining therapeutic efficacy.


Asunto(s)
Leucemia Mieloide Aguda , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Humanos , Histona Demetilasas/genética , Histona Demetilasas/metabolismo , Histona Demetilasas con Dominio de Jumonji , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Proteínas Proto-Oncogénicas c-bcl-2/genética
11.
Indian J Community Med ; 47(2): 202-206, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36034253

RESUMEN

Background: Despite the low level of clinical evidence in hydroxychloroquine (HCQ) favor, it was prescribed for pre- and post-exposure prophylaxis in India and worldwide. In absence of a large randomized control trial, the evidence needs to be generated through observation study, hence the study was conducted to find the evidence for prophylaxis of HCQ. Materials and Methods: A multi-centric cross-sectional study involving government hospitals was chosen for serosurvey conducted from August 21, 2020, to November 20, 2020. Questionnaire was adopted from WHO. Data about chloroquine (CQ) use among health-care workers (HCWs) were added and the duration of CQ intake was also noted. Results: A total of 2,224 HCWs were recruited. The mean duration of time of taking HCQ was 7.1 weeks (standard deviation ± 6.1 weeks, median = 4 weeks with IQR, 3-10 weeks). Training on personal protective equipment (PPE), knowledge of handwashing, direct care to the patient, availability of alcohol hand rub, close contact with the patient, duration of contact, and usage of PPE were associated with HCQ intake. The antibody formation in group taking HCQ was 16.9% compared to 19.8% not taking it (P = 0.08). The Chi-square for linear trend for weeks of HCQ intake and antibody formation. However, the same was not statistically significant (Chi-square = 3.61, P = 0.06). Conclusion: Our study did not find a statistically significant association in the large multicentric study. The absolute difference of 2.9% in the two groups may not be sufficient to warrant its widespread use for prophylaxis.

12.
Org Biomol Chem ; 20(7): 1415-1424, 2022 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-35014658

RESUMEN

An expeditious synthetic route to access functionalized pyrrolo[2,1-b]quinazoline scaffolds has been achieved via domino ring opening cyclization (DROC) reactions of donor-acceptor (D-A) cyclopropanes and 2-amino(methyl)aniline derivatives. This novel iron catalyzed transformation is amenable to a wide range of substrates. Three new C-N bonds and two rings were sequentially constructed in this divergent one-pot process. The advantages of simple operation, high yields and general applicability make this procedure highly attractive and practical too.

13.
Med J Armed Forces India ; 77: S264-S270, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34334892

RESUMEN

BACKGROUND: On 16 Jan 2021, India launched its immunization program against COVID-19. Among the first recipients were 1.59 million Health Care Workers (HCWs) and Frontline Workers (FLWs) of the Indian Armed Forces, who were administered COVISHIELD (Astra Zeneca). We present an interim analysis of vaccine effectiveness (VE) estimates till 30 May 2021. METHODS: The VIN-WIN cohort study was carried out on anonymized data of HCWs and FLWs of Indian Armed Forces. The existing surveillance system, enhanced for COVID-19 monitoring, was sourced for data. The cohort transitioned from Unvaccinated (UV) to Partially Vaccinated (PV) to Fully Vaccinated (FV), serving as its own internal comparison. Outcomes studied in the three groups were breakthrough infections and COVID related deaths. Incidence Rate Ratio (IRR) was used to compare outcomes among the three groups to estimate VE. RESULTS: Data of 1,595,630 individuals (mean age 27.6 years; 99% male) over 135 days was analysed. Till 30 May 21, 95.4% and 82.2% were partially and fully vaccinated. The UV, PV and FV compartments comprised 106.6, 46.7 and 58.7 million person-days respectively. The number of breakthrough cases in the UV, PV and FV groups were 10061, 1159 and 2512; while the deaths were 37, 16 and 7 respectively. Corrected VE was 91.8-94.9% against infections. CONCLUSION: Interim results of the VIN-WIN cohort study of 1.59 million HCWs and FLWs of Indian Armed Forces showed a ∼93% reduction in COVID-19 breakthrough infections with COVISHIELD vaccination.

14.
Med J Armed Forces India ; 77: S359-S365, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34334905

RESUMEN

BACKGROUND: Serosurveys provide the prevalence of infection and over time will reveal the trends. The present study was conducted to estimate the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among healthcare workers (HCWs) and to analyse various characteristics (risk factors) associated with SARS CoV-2 infection. METHODS: Eight government designated Corona virus disease -19 (COVID-19) hospitals were selected based on the hospital admission of patients with COVID-19 and the local epidemiological situation in the region. Multistage population proportion to size sampling was performed for the selection of HCWs. Serosurvey was conducted using the enzyme-linked immunosorbent assay-based IgG antibody test (COVID KAVACH). Bivariate and multiple logistic regression was performed to find out the factor/factors associated with the positive antibody test. RESULTS: Out of 3255 HCWs that participated in the study, data of 3253 were analysed. The seroprevalence was 19.7% (95% confidence interval: 18.5-21.3%). Factors associated were location, category of HCWs, male sex, previously tested positive by the molecular test, training on infection prevention and control, personal protective measures, handwashing technique, close contact with a patient confirmed with COVID-19, use of personal protective equipment and symptoms in the last 30 days. However, in multiple logistic regression, only location, category, previously tested positive by the molecular test and symptoms in the last 30 days were statistically significant. CONCLUSION: HCWs are vulnerable to SARS-CoV-2 infection. One in five HCWs had detectable antibodies. The presence of antibodies among HCWs may help in their placement and triage. HCWs may be advised to report early in case of any symptoms of COVID-19. Preventive measures may be targeted based on the location, with particular emphasis on ancillary workers and nurses.

15.
Chemosphere ; 279: 130515, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33862360

RESUMEN

Convenient one-pot synthetic route for the fabrication of carbon dots (CDs) from Tagetes erecta flower (TEF), named as "TEF-CDs', through solvo(hydro)-thermal carbonization of the TEF was developed. The TEF-CDs revealed high selectivity towards chlorpyrifos and quinalphos, acting as a fluorescent probe. The CDs synthesized from T. erecta flower showed a strong blue color at 495 nm when excited at 420 nm, along with the exhibition of a strong quantum yield of 63.7%. The synthesized CDs revealed their richness in the surface-active organic group that synthesized CDs from T. erecta flower are mainly comprised of C, O, and N, which were crystalline in structure that was revealed by TEM image and XRD spectra. Furthermore, when the probe was exposed to different pH conditions, no major noticeable changes were recorded. Moreover, when the probe was exposed to chlorpyrifos and quinalphos, we have noticed that fluorescence spectra was turned off when the probe was exposed to chlorpyrifos and "turned on" after the exposure quinalphos. Moreover, fluorescence spectral changes showed a good linearity with chlorpyrifos and quinalphos concentrations in the range of 0.05-100.0 µM for chlorpyrifos and 0.01-50.0 µM for quinalphos. The limit of detection are 2.1 ng mL-1 and 1.7 ng mL-1 for chlorpyrifos and quinalphos, respectively. Finally, the TEF-CDs-based fluorescent nanoprobe was successfully applied to estimate chlorpyrifos and quinalphos with an effective accuracy in rice and fruit samples with rapid detection time.


Asunto(s)
Cloropirifos , Puntos Cuánticos , Tagetes , Carbono , Colorantes Fluorescentes , Compuestos Organotiofosforados
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 215: 209-217, 2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-30840923

RESUMEN

Herein, we fabricated fluorescent gold nanoclusters (Au NCs) by using trypsin as a ligand. The fabricated trypsin-Au NCs emit bright red color fluorescence upon the exposure of 365 nm UV light. The trypsin-Au NCs are stable and well dispersed in water, which exhibited strong red emission peak at 665 nm upon excitation wavelength of 520 nm. The red fluorescence of trypsin-Au NCs was greatly quenched by the addition of multiple analytes such as drugs (carbidopa and dopamine) and three divalent metal ions (Cu2+, Co2+ and Hg2+ ion). As a result, a novel fluorescence "turn-off" probe was developed for the detection of the above analytes with good selectivity and sensitivity. This method exhibits the detection limits for carbidopa, dopamine, Cu2+, Co2+ and Hg2+ ions are 6.5, 0.14, 5.2, 0.0078, and 0.005 nM, respectively. The trypsin-Au NCs were successfully applied to detect drugs (carbidopa, and dopamine) in pharmaceutical samples and metal ions (Cu2+, Co2+ and Hg2+ ion) in biofluids and water samples, exhibiting good precision and accuracy, which offers a facile analytical strategy for assaying of the above analytes in pharmaceutical and biological samples.


Asunto(s)
Técnicas Biosensibles/métodos , Oro/química , Nanopartículas del Metal/química , Espectrometría de Fluorescencia/métodos , Tripsina/metabolismo , Carbidopa/análisis , Dopamina/análisis , Colorantes Fluorescentes/química , Límite de Detección , Modelos Lineales , Metales Pesados/análisis , Reproducibilidad de los Resultados , Tripsina/química
19.
3 Biotech ; 8(1): 33, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29291146

RESUMEN

The tannase production ability by endophytic actinobacteria and the genetic identity of responsible tannase gene were determined. The studied strains were isolated from surface-sterilized leaf discs of Ailanthus excelsa Roxb. Four strains were found to hydrolyze tannic acid on solid media containing 0.4% tannic acid. The strain AL1L was found as tanBLP indicating production of tannase with diverse of substrate affinity. The tannase production from the potential strain AL1L was performed in liquid tannic acid broth (0.4%, w/v). The strain was later identified as Streptomyces sp. AL1L on the basis of 16S rDNA homology. Highest enzyme activity was observed at 48 h of incubation at the exponential growth phase. The enzyme was purified by ammonium sulfate precipitation followed by dialysis (15 kD cut off). This enzyme, with molecular weight 180 kD shows highest catalytic activity at 35 °C, pH 6 with substrate concentration 0.1 g%. The purified enzyme possesses 1.4 × 10-3 Km and 11.15 U/ml as Vmax. The above study indicates high industrial prospective of endophytic actinobacteria as source of tannase of potential biotechnological applications.

20.
Microbiol Insights ; 9: 1-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26997870

RESUMEN

This study was conducted to isolate endophytic bacteria possessing anti-infective property from Kalmegh (Andrographis paniculata Nees.), a well-known medicinal plant. A total of 23 strains were isolated from this plant among which the strain KL1, isolated from surface-sterilized leaf of this medicinal herb, showed broad-spectrum antagonism against an array of Gram-positive and -negative bacterial pathogens. Ethyl acetate extract of KL1-fermented media yielded a greenish amorphous substance retaining anti-infective property. Solvent-extracted crude material was separated by thin-layer chromatography, and the active ingredient was located by autobiogram analysis. The purified anti-infective compound was found as anthracene derivative as analyzed by ultraviolet and Fourier transform infrared spectroscopy. The strain was identified as Bacillus thuringiensis KL1 from cultural, physiochemical, and molecular aspects. The above results indicate the pharmaceutical potential of the candidate isolate.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...