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1.
Molecules ; 28(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36677695

RESUMO

The widespread and indiscriminate use of broad-spectrum antibiotics leads to microbial resistance, which causes major problems in the treatment of infectious diseases. However, advances in nanotechnology have opened up new domains for the synthesis and use of nanoparticles against multidrug-resistant pathogens. The traditional approaches for nanoparticle synthesis are not only expensive, laborious, and hazardous but also have various limitations. Therefore, new biological approaches are being designed to synthesize economical and environmentally friendly nanoparticles with enhanced antimicrobial activity. The current study focuses on the isolation, identification, and screening of metallotolerant fungal strains for the production of silver nanoparticles, using antimicrobial activity analysis and the characterization of biologically synthesized silver nanoparticles by X-ray diffraction (XRD) spectroscopy, energy-dispersive X-ray spectroscopy (EDX), and scanning electron microscopy (SEM). In total, 11 fungal isolates were isolated and screened for the synthesis of AgNPs, while the Penicillium notatum (K1) strain was found to be the most potent, demonstrating biosynthetic ability. The biologically synthesized silver nanoparticles showed excellent antibacterial activity against the bacteria Escherichia coli (ATCC10536), Bacillus subtilis, Staphylococcus aureus (ATCC9144), Pseudomonas aeruginosa (ATCC10145), Enterococcus faecalis, and Listeria innocua (ATCC13932). Furthermore, three major diffraction peaks in the XRD characterization, located at the 2θ values of 28.4, 34.8, 38.2, 44, 64, and 77°, confirmed the presence of AgNPs, while elemental composition analysis via EDX and spherical surface topology with a scanning electron microscope indicated that its pure crystalline nature was entirely composed of silver. Thus, the current study indicates the enhanced antibacterial capability of mycologically synthesized AgNPs, which could be used to counter multidrug-resistant pathogens.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Prata/farmacologia , Prata/química , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Antibacterianos/química , Bactérias , Espectrometria por Raios X , Desenvolvimento Muscular , Espectroscopia de Infravermelho com Transformada de Fourier , Extratos Vegetais/química
2.
Am J Med Genet A ; 188(9): 2693-2700, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35703069

RESUMO

Mitochondrial protein synthesis requires three elongation factors including EF-Tu (TUFM; OMIM 602389), EF-Ts (TSFM; OMIM 604723), and EF-G1 (GFM1; OMIM 606639). Pathogenic variants in any of these three members result in defective mitochondrial translation which can impart an oxidative phosphorylation (OXPHOS) deficiency. In this study, we investigated a consanguineous Pakhtun Pakistani family. There were four affected siblings at the time of this study and one affected girl had died in infancy. The index patient had severe intellectual disability, global developmental delay, dystonia, no speech development, feeding difficulties, and nystagmus. MRI brain presented thinning of corpus callosum and polymicrogyria. Whole exome sequencing revealed a novel compound heterozygous variant in GFM1 located on chromosome 3q25.32. Sanger sequencing confirmed recessive segregation of the maternal (NM_001308164.1:c.409G > A; p.Val137Met) and paternal (NM_001308164.1:c.1880G > A; p.Arg627Gln) variants in all the four affected siblings. These variants are classified as "likely-pathogenic" according to the recommendation of ACMG/AMP guideline. GFM1 alterations mostly lead to severe phenotypes and the patients may die in early neonatal life; however, four of the affected siblings had survived till the ages of 10-17 years, without developing any life-threatening conditions. Mostly, in cousin marriages, the pathogenic variants are identical-by-descent, and affected siblings born to such parents are homozygous. Three homozygous variants were shortlisted in the analysis of the WES data, but Sanger sequencing did not confirm their segregation with the disease phenotype. This is the first report from Pakistan expanding pathogenicity of GFM1 gene.


Assuntos
Distonia , Distúrbios Distônicos , Deficiência Intelectual , Polimicrogiria , Distonia/genética , Exoma/genética , Humanos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Proteínas Mitocondriais/genética , Mutação , Linhagem , Fator G para Elongação de Peptídeos/genética , Fatores de Alongamento de Peptídeos/genética , Polimicrogiria/genética , Sequenciamento do Exoma
3.
World J Microbiol Biotechnol ; 38(11): 197, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35989357

RESUMO

Low-Density Polyethylene (LDPE) is one of the significant environmental pollutants as it is resistant to natural degradation. In this study, we reported the LDPE-degrading bacterial strain i.e., Exiguobacterium sp. strain LM-IK2 isolated from plastic dumped soil which shows potential degradation capability. The percent weight loss of LDPE was calculated as - 5.70 ± 0.7 after 90 days of incubation in a carbon-free MSM medium. The Field Emission Scanning Electron Microscopy (FE-SEM) analysis shows that LDPE films show slight surface disruption after treatment with bacteria. The Fourier Transform Infrared Spectroscopy (FTIR) revealed the chemical changes in LDPE films e.g., formation and reduction of typical carbonyl peaks after incubation with bacteria. The X-Ray Diffraction (XRD) analysis displayed an increase in percent crystallinity, with a slight change in total carbon content. Genetic analysis showed the presence of Laccase (167 bp) and Alkane Hydroxylase (330 bp) genes that are responsible for LDPE degradation. Thus, Exiguobacterium sp. strain LM-IK2 has the potential to degrade LDPE and could be further explored to improve its efficiency in the bioremediation of LDPE.


Assuntos
Polietileno , Solo , Bactérias/metabolismo , Biodegradação Ambiental , Exiguobacterium , Plásticos , Polietileno/química
4.
Pak J Pharm Sci ; 34(1): 85-94, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34248007

RESUMO

Extra-Intestinal Escherichia coli (ExPEC) are important cause of Urinary Tract Infections (UTIs) and systemic infections. The purpose of this study was to investigate numerous ExPEC bacterial isolates for phenotypic virulence characteristics including hemolytic activity and resistance pattern and to observe their association with genetic traits via Polymerase Chain Reaction (PCR). A total of 367 ExPEC isolates were collected from patients admitted in Khyber Teaching Hospital (KTH) Peshawar, Pakistan. Standard techniques were used for identification of isolates, determination of hemolytic potential and antimicrobial susceptibility testing. PCR was used for screening of virulence genes using specific primers. A total of 367 ExPEC isolates were characterized, among which 62.7, 24.3, 7.1 and 6% were isolated from urine, pus, sputum and wound specimens, respectively. Majority of the isolates (82.8%) were hemolysin positive. Multi drug resistance pattern was shown by 41% of the isolates and harbored at least one virulence gene (71.7%), of which sat was the most prevalent (64.3%). The highest resistance was found to cefotaxime (99.2%), ampicillin (97.5%) and aztreonem (89.6%). 15 different virulence genes combinations were observed in the current study. A total of 16 virotypes (15 of positive virulence genes and one of no virulence gene) were observed in the current study. The current investigation showed a high prevalence of sat and hlyA genes among ExPEC isolate, suggesting a role of these genes in the pathogenesis of ExPEC.


Assuntos
Infecções por Escherichia coli/epidemiologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Fenótipo , Fatores de Virulência/genética , Fatores de Virulência/isolamento & purificação , Adulto , Estudos Transversais , Infecções por Escherichia coli/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Estudos Prospectivos
5.
BMC Vet Res ; 16(1): 234, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641048

RESUMO

BACKGROUND: Tea polyphenols (TPs) attenuate obesity related liver inflammation; however, the anti-obesity effects and anti-inflammatory mechanisms are not clearly understood. This study aimed to determine whether the anti-obesity and anti-inflammatory TPs mechanisms associated with cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression levels, and obesity-related gene response in dogs. RESULTS: Dogs fed TPs displayed significantly decreased (p < 0.01) mRNA expression of tumor necrosis factor-α (TNF-α), interleukin-1 beta (IL-1ß), and interleukin-6 (IL-6) compared to dogs that consumed high-fat diet (HFD) alone. TPs significantly (p < 0.01) inhibited COX-2 and iNOS expression level, and decreased liver fat content and degeneration. CONCLUSION: These results suggested that TPs act as a therapeutic agent for obesity, liver inflammation, and fat degeneration via COX-2 and iNOS inhibition, with TNF-α, IL-1ß, and IL-6 involvement.


Assuntos
Camellia sinensis/química , Ciclo-Oxigenase 2/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/genética , Obesidade/veterinária , Polifenóis/farmacologia , Animais , Anti-Inflamatórios , Doenças do Cão/tratamento farmacológico , Cães , Inflamação/veterinária , Obesidade/tratamento farmacológico
6.
Pak J Pharm Sci ; 33(6(Supplementary)): 2739-2750, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33879432

RESUMO

The rapid spread of Metallo-ß-Lactamases producing Gram-negative bacteria in Pakistan is alarming and novel inhibitors with multi inhibition potential are required. In the current study, an effort was made to identify the resistance genes of MBLs producing E. coli and single inhibitor was designed having the potential to block all resistant proteins. Results showed that out of 573 clinical isolates, 14.1% MBLs producers have NDM-1 (27.2%) and VIM (13.6%) gene. The isolates were resistant to MEM, AMP, AMC, FEP, CTX, LEV and ATM, while effective antibiotics were TGC, CO, FOS and AK with MICs ranging from 4 to >32µg/ml. RECAP synthesis was used for de-novo discovery of 1000 inhibitors and protein crystal structures were retrieved from PDB. Active sites were identified in each protein and to improve ADMET properties, Lipinski's rules of five was applied. Placement of the ligand was done by London dG algorithm implemented in MOE. For final refinement, GBVI/WSA dG algorithm was used. Based on docking score, visual inspection of ligands interaction with key residues, binding affinity and binding energy of ligands with proteins, 10 compounds were selected for MBLs proteins which presented best ADMET properties, binding energy and affinity than the reported ones.


Assuntos
Escherichia coli/efeitos dos fármacos , Inibidores de beta-Lactamases/farmacologia , beta-Lactamases/genética , Desenho de Fármacos , Farmacorresistência Bacteriana , Escherichia coli/enzimologia , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Fenótipo , Inibidores de beta-Lactamases/química , beta-Lactamases/química
7.
Cryobiology ; 87: 91-98, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30707961

RESUMO

Accurate reprogramming of DNA methylation occurring in preimplantation embryos is critical for normal development of both fetus and placenta. Environmental stresses imposed on oocytes usually cause the abnormal DNA methylation reprogramming of early embryos. However, whether oocyte vitrification alters the reprogramming of DNA methylation (5 mC) and its derivatives in mouse preimplantation embryo development remains largely unknown. Here, we found that the rate of cleavage and blastocyst formation of embryos produced by IVF of vitrified matured oocytes was significantly lower than that in control counterparts, but the quality of blastocysts was not impaired by oocyte vitrification. Additionally, although vitrification neither altered the dynamic changes of 5-hydroxymethylcytosine (5hmC) and 5-formylcytosine (5 fC) before 4-cell stage nor affected the levels of 5 mC and 5-carboxylcytosine (5caC) throughout the preimplantation development, vitrification significantly reduced the levels of 5hmC and 5 fC from 8-cell stage onwards. Correspondingly, vitrification did not alter the expression patterns of Tet3 in preimplantation embryos but apparently reduced the expression levels of Tet1 in 4-cell and 8-cell embryos and increased the expression levels of Tet2 at morula stage. Taken together, these results demonstrate that oocyte vitrification perturbs DNA methylation reprogramming in mouse preimplantation embryo development.


Assuntos
Blastocisto/citologia , Criopreservação/métodos , Metilação de DNA/genética , Oócitos/citologia , Oogênese/fisiologia , Vitrificação , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/química , Animais , Citosina/análogos & derivados , Citosina/química , Proteínas de Ligação a DNA/biossíntese , Dioxigenases/biossíntese , Desenvolvimento Embrionário , Feminino , Fertilização in vitro/métodos , Metáfase , Camundongos , Mórula/fisiologia , Gravidez , Proteínas Proto-Oncogênicas/biossíntese
8.
Environ Monit Assess ; 191(10): 622, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31494726

RESUMO

Bioleaching of heavy metals from industrial contaminated soil using metallotolerant fungi is the most efficient, cost-effective, and eco-friendly technique. In the current study, the contaminated soil samples from Hattar Industrial Estate revealed a total lead (Pb) and mercury (Hg) concentration of 170.90 mg L-1 and 26.66 mg L-1, respectively. Indigenous metallotolerant fungal strains including Aspergillus niger M1, Aspergillus fumigatus M3, Aspergillus terreus M6, and Aspergillus flavus M7 were isolated and identified by pheno- and genotyping. A. fumigatus and A. flavus of soil sample S1 showed higher efficiency for Pb removal (99.20% and 99.30%, respectively), in SDB medium. Likewise, A. niger and A. terreus of soil sample S2 showed higher efficiency for Hg removal (96% and 95.50%, respectively), in YPG medium. Furthermore, the maximum uptake efficiency for Pb removal (8.52 mg g-1) from soil sample S1 was noticed for A. fumigatus in YPG medium, while the highest uptake efficiency (4.23 mg g-1) of A. flavus M2 strain was observed with CYE medium. Similarly, the maximum uptake efficiency of 0.41 mg g-1 and 0.44 mg g-1 for Hg removal from soil sample S2 was found for A. niger and A. terreus strains, respectively, in CYE medium. Thus, in order to address the major issue of industrial waste pollution, indigenous fungal strains A. fumigatus (M1) and A. terreus (M7), isolated in this study, could be used (ex situ or in situ) to remediate soils contaminated with Pb and Hg.


Assuntos
Aspergillus/metabolismo , Chumbo/metabolismo , Mercúrio/metabolismo , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Solo/química , Aspergillus/classificação , Aspergillus/genética , Monitoramento Ambiental , Recuperação e Remediação Ambiental , Genótipo , Resíduos Industriais , Chumbo/análise , Mercúrio/análise , Metais Pesados/análise , Fenótipo , Poluentes do Solo/análise
9.
Environ Monit Assess ; 191(9): 585, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31440913

RESUMO

Remediation of heavy metals, other than microbial bioleaching method, is expensive and unsuitable for large contaminated areas. The current study was aimed to isolate, identify, and test the potential of indigenous fungal strains for heavy metal removal from contaminated soil. A total of three metallotolerant fungal strains, i.e., Aspergillus niger (M1DGR), Aspergillus fumigatus (M3Ai), and Penicillium rubens (M2Aii), were isolated and identified by phenotyping and genotyping from heavy metal-contaminated soil of  Hattar Industrial Estate, Pakistan. A. niger was found to be the most successful strain for the removal of heavy metals from the contaminated soil with maximum bioaccumulation efficiency of 98% (Cd) and 43% (Cr). In contrast, A. fumigatus showed comparatively low but still considerable bioleaching potential, i.e., 79% and 69% for Cd and Cr removal, respectively. Maximum metal uptake efficiency, i.e., 0.580 mg g-1 and 0.152 mg g-1 by A. niger strain was noticed for Cd and Cr with Czapek yeast extract (CYE) and Sabouraud dextrose broth (SDB) media, respectively. A. fumigatus (M3Ai) exhibited the maximum bioleaching capacity (0.40 mg g-1) for Cr with CYE medium. The results reveal that A. niger M1DGR and A. fumigatus M3Ai could be used to develop new strategies to remediate soil contaminated with heavy metals (Cd and Cr) through either in situ or ex situ mycoremediation.


Assuntos
Aspergillus flavus/metabolismo , Aspergillus fumigatus/metabolismo , Cádmio/análise , Cromo/análise , Penicillium/metabolismo , Poluentes do Solo/análise , Biodegradação Ambiental , Monitoramento Ambiental , Poluição Ambiental/análise , Paquistão , Solo/química
10.
J Pak Med Assoc ; 68(6): 953-955, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30323368

RESUMO

Progressive familial intrahepatic cholestasis (PFIC) is one of the causes of childhood end stage liver disease. It is an autosomal recessive disorder, characterized by pruritus, coagulopathy, growth retardation, jaundice, and subsequently cirrhosis and hepatic failure due to impaired bile acid transport and metabolism. Diversion of bile, internally or externally, from the terminal ileum, to decrease re-uptake, is a viable option for relieving pruritus. Four children with PFIC type1 were treated with partial internal biliary diversion (PIBD) from June 2014 To March 2017 in the Unit of Paediatric surgery, Jinnah Hospital Lahore. The ages of patients were from four months to five years. Three were girls and one was a boy. The main symptom common to all was intractable pruritus. There was relief in pruritus, observed within first week postoperatively. They had been able to sleep without pruritis associated awakening episodes. PIBD is an effective technique for relieving the most devastating symptom of pruritus in PFIC.


Assuntos
Procedimentos Cirúrgicos do Sistema Biliar/métodos , Colestase Intra-Hepática/complicações , Colo Ascendente/cirurgia , Vesícula Biliar/cirurgia , Jejuno/cirurgia , Prurido/etiologia , Anastomose Cirúrgica , Pré-Escolar , Colestase Intra-Hepática/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório , Feminino , Humanos , Lactente , Masculino , Índice de Gravidade de Doença
11.
J Pak Med Assoc ; 68(6): 955-958, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30323369

RESUMO

This is a retrospective study of seven patients with post-traumatic and iatrogenic urethrocutaneous fistula of penile urethra, excluding complication of hypospadias surgery. It was conducted in the Paediatric Surgery Department, Jinnah Hospital Lahore from June 2014 to January 2017. The patients ages ranged from three to twelve years. All the patients were managed by repairing the fistula in three layers electively at 3 months from the date of initial presentation. They remain well with no complaints except one with a recurrence. The complications of circumcision can be avoided by preventing circumcision by non-doctors and quacks.


Assuntos
Circuncisão Masculina/efeitos adversos , Fístula Cutânea/cirurgia , Doença Iatrogênica , Pênis/lesões , Doenças Uretrais/cirurgia , Procedimentos Cirúrgicos Urológicos Masculinos/métodos , Ferimentos e Lesões/complicações , Criança , Pré-Escolar , Fístula Cutânea/etiologia , Humanos , Masculino , Estudos Retrospectivos , Doenças Uretrais/etiologia
12.
Pak J Pharm Sci ; 31(1): 83-87, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29348088

RESUMO

The current study was designed in order to elucidate the most sensitive method for daily practice as well as to evaluate the risk factors for HCV infection associated with blood transfusion in District Peshawar. A total of 1400 healthy volunteer blood donors were tested for Anti-HCV. A questionnaire was used to evaluate the risk factors. Initial testing of all blood samples was done by Immuno Chromatographic Technique (ICT) and confirmed by micro particle enzyme immunoassay (MEIA) and Enzyme Linked Immunosorbent Assay (ELISA). The comparison among ICT, ELISA and MEIA techniques was also evaluated for the purpose of sensitivity. Among 1400 blood donors, 26 (1.85%) cases were found positive for Anti-HCV. These 26 cases were positive on MEIA, 16 individuals were positive on ELISA while 14 were positive on ICT. These 26 cases had different histories of dental treatment (50%), traveled abroad (23.07%), surgery (11.53%), blood transfusion (7.69%) and unknown reason (7.69%). Among all these different histories of dental treatment and blood transfusion were the main risk factors for HCV infection. The results revealed that MEIA is a quick and reliable technique for routine screening of blood donors particularly for controlling the spread of HCV.


Assuntos
Doadores de Sangue , Anticorpos Anti-Hepatite C/sangue , Hepatite C/sangue , Hepatite C/epidemiologia , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Paquistão/epidemiologia , Prevalência , Fatores de Risco , Sensibilidade e Especificidade
13.
Pak J Pharm Sci ; 31(2): 371-377, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29618423

RESUMO

The current study focused on the pharmacological activities of Justicia adhatoda; including antibacterial, antifungal, phytotoxic, cytotoxic, haemagglutination, insecticidal, in vitro antiglycation, DPPH antioxidant and anti-termite. The crude methanolic extract (Crd. Met. Ext) showed 46.4 % antibacterial activity against M. morganii while the n-hexane fraction showed good (71.4%) and moderate (55.1%) activity against M. morganii and A. baumannii respectively. The EtOAc and aqueous fractions, in most of the cases, showed low to no activity against the selected bacterial pathogens, against A. niger, T. harzianum, A. parasiticus and V. dahliae. The Crd. Met. Ext and fractions showed low activity, against P. notatum and P. digitatum, Crd. Met. Ext. and all fractions were inactive. The percent growth regulation, in case of phytotoxic activity, by Crd. Met. Ext was 25 and 16.6, n-hexane fraction 16.6, 16.6 and 0, CHCl3 25, 8.33 and 0 % and EtOAc fractions 8.33, 8.33 and 0% at 1000 and 100 and 10µg/ml respectively. The aqueous fraction was inactive at all the test concentrations. The results of brine shrimp cytotoxic activity for Crd. Met. Ext was 13.33% and n-hexane fraction 20% at 1000, µg/ml respectively. All of the other fractions showed low to no activity at different test concentrations. All of the test samples were inactive against RBC's of the blood groups at all concentration indicating that the selected plant lack phytolectins and haemagglutination activity. The Crd. Met. Ext and various fraction showed low activity against the test insects i.e. C. pulicaria, C. chinensis and T. castaneum. The absorbance value of plant extract for anti-glycation activity at various concentration were: 0.08, 0.067, 0.053 and 0.04 in comparison with Aminoguanidine 0.04, 0.035, 0.03 and 0.02 respectively at 10, 50, 90 and 130µl. The DPPH radical scavenging activities were proportional to the concentration of the fractions, as the concentration of these increased, the percent scavenging activity also increased. The CHCl3 and EtOAc fractions killed all the termites in 24 hours while Crd. Met. Ext, n-hexane and aqueous fractions took 2-3 days.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Inseticidas/farmacologia , Justicia/química , Animais , Artemia/efeitos dos fármacos , Hemaglutinação/efeitos dos fármacos , Isópteros/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais/química
14.
Crit Rev Biotechnol ; 36(1): 99-107, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25025277

RESUMO

l-Malic acid has many uses in food, beverage, pharmaceutical, chemical and medical industries. It can be produced by one-step fermentation, enzymatic transformation of fumaric acid to l-malate and acid hydrolysis of polymalic acid. However, the process for one-step fermentation is preferred as it has many advantages over any other process. The pathways of l-malic acid biosynthesis in microorganisms are partially clear and three metabolic pathways including non-oxidative pathway, oxidative pathway and glyoxylate cycle for the production of l-malic acid from glucose have been identified. Usually, high levels of l-malate are produced under the nitrogen starvation conditions, l-malate, as a calcium salt, is secreted from microbial cells and CaCO3 can play an important role in calcium malate biosynthesis and regulation. However, it is still unclear how it is secreted into the medium. To enhance l-malate biosynthesis and secretion by microbial cells, it is very important to study the mechanisms of l-malic acid biosynthesis and secretion at enzymatic and molecular levels.


Assuntos
Bactérias/metabolismo , Fermentação , Fumarato Hidratase/metabolismo , Malatos/metabolismo , Bactérias/citologia , Indústria Alimentícia , Fumarato Hidratase/química , Glucose/metabolismo , Glioxilatos/metabolismo , Hidrólise , Malatos/química
15.
Pharm Biol ; 54(11): 2547-2554, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27159021

RESUMO

CONTEXT: Endophytic fungi, being a prolific source of bioactive secondary metabolites, are of great interest for natural product discovery. OBJECTIVE: Isolation and partial characterization of endophytic fungi inhabiting the leaves and woody parts of Taxus fuana Nan Li & R.R. Mill. (Taxaceae) and evaluation of biological activity. MATERIALS AND METHODS: Endophytic fungal isolates were identified by molecular analysis of internal transcribed spacer (ITS) regions of 18S rDNA. Extracts of the endophytic fungi cultured on potato dextrose agar and modified medium were evaluated using cancer chemoprevention bioassays [inhibition of TNF-α-induced NFκB, aromatase and inducible nitric oxide synthase (iNOS); induction of quinone reductase 1 (QR1)] and growth inhibition with MCF-7 cells. RESULTS: Nine of 15 fungal isolates were identified as belonging to Epicoccum, Mucor, Penicillium, Chaetomium, Paraconiothriym, Plectania or Trichoderma. Five of the 15 extracts inhibited NFκB activity (IC50 values ranging between 0.18 and 17 µg/mL) and five inhibited iNOS (IC50 values ranging between 0.32 and 12.9 µg/mL). In the aromatase assay, only two isolates mediated inhibition (IC50 values 12.2 and 10.5 µg/mL). With QR1 induction, three extracts exhibited significant activity (concentrations to double activity values ranging between 0.20 and 5.5 µg/mL), and five extracts inhibited the growth of MCF-7 cells (IC50 values ranging from 0.56 to 17.5 µg/mL). Six active cultures were derived from woody parts of the plant material. CONCLUSION: The endophytic fungi studied are capable of producing pharmacologically active natural compounds. In particular, isolates derived from the wood of Taxus fuana should be prioritized for the isolation and characterization of bioactive constituents.


Assuntos
Anticarcinógenos/isolamento & purificação , Endófitos/isolamento & purificação , Taxus/microbiologia , Anticarcinógenos/farmacologia , Inibidores da Aromatase/farmacologia , Endófitos/metabolismo , Humanos , Células MCF-7 , NAD(P)H Desidrogenase (Quinona)/biossíntese , NF-kappa B/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores
17.
Pak J Pharm Sci ; 29(6): 1977-1983, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28375113

RESUMO

Staphylococcus aureus is a nosocomial pathogen that resides in the soft tissues causing many diseases. The current study was conducted to determine the prevalence of Methicillin Resistant S. aureus (MRSA) in ear discharge and pus of patients and antibacterial activity of crude methanolic extract (Cr. MeOH Ext.) and various fractions of M. Africana and V. agnus castus against clinical isolates of MRSA. A total of 40 samples were collected from ear, nose and throat (ENT) outpatient department and wards of Khyber Teaching Hospital (KTH), Peshawar. Out of 40 samples, 36 (90%) samples showed growth on Mannitol Salt Agar (MSA) media out of which 9(25%) were MRSA and the remaining 27(75%) were methicillin susceptible S. aureus (MSSA). A good antibacterial activity was observed for the Cr. MeOH Ext. (76.1%) and ethyl acetate (EtOAc) fraction of V. agnus castus against S11 (71.4%). The n-hexane fraction also showed good antibacterial effect (70%) against S26. The chloroform (CHCl3), butanol (BuOH) and aqueous fractions of M. africana showed good antibacterial activity against S11 (71.4%), S32 (70%) and S26 (75%), respectively. The above results revealed that the selected plants can be further utilized for isolation of the active ingredients as the crude extracts were found good for inhibition of MRSA.


Assuntos
Antibacterianos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Metanol/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Primulaceae/química , Solventes/química , Vitex/química , Acetatos/química , Antibacterianos/isolamento & purificação , Butanóis/química , Clorofórmio/química , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Medicamentos de Ervas Chinesas/isolamento & purificação , Hexanos/química , Hospitais de Ensino , Humanos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Paquistão , Fitoterapia , Componentes Aéreos da Planta/química , Plantas Medicinais , Água/química
18.
Pak J Pharm Sci ; 29(3): 991-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27166544

RESUMO

In the current study, the antimicrobial, phytotoxic, haemagglutination and antioxidant potential of crude methanolic extract (Crd. MeOH Ext.) and four organic fractions of Arisaema tortuosum was investigated. All fractions have been screened for antimicrobial properties against eight bacterial pathogens and six fungal pathogens using agar well diffusion and tube dilution method, respectively. Furthermore, the organic fractions were also screened for its phytotoxicity against Lemna minor. Haemagglutination was performed against all human blood groups while free radical scavenging activity was performed to investigate the antioxidant potential of A. tortuosum. Results obtained for antibacterial activity exhibited various degree of zone of inhibition and significant activity was observed for Pseudomonas aeruginosa (27.16±0.60) followed by Bacillus cereus (18.55±0.69) for Crd. MeOH Ext. and chloroform (CHCl3) fraction, respectively while some strains showed resistant at same concentration. Similarly, non-significant antifungal activity was observed for the plant extracts. However, the highest activity among the strains was observed for Alternaria alternata (22±1.24%) and Aspergillus niger (20±1.00%) for ethyl acetate (EtOAc) fraction and Crd. MeOH Ext., respectively. The plant extracts showed good phytotoxic activity with 77.06% inhibition for n-hexane fraction at 1000µg/mL. The result of Nitric Oxide (NO) reducing assay revealed that the plant has less antioxidant activity with 46.06% inhibition for CHCl(3) fraction at 900µg/mL. For haemagglutination assay, the result displayed no agglutination in all the testing concentration. Based on the current results, it can be concluded that A. tortuosum has significant antimicrobial and moderate phytotoxic potential and therefore can leads to antibiotics and herbicide production.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Arisaema/química , Hemaglutinação/efeitos dos fármacos , Herbicidas/farmacologia , Extratos Vegetais/farmacologia , Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Fracionamento Químico , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana , Testes de Hemaglutinação , Herbicidas/isolamento & purificação , Humanos , Óxido Nítrico/química , Oxirredução , Fitoterapia , Componentes Aéreos da Planta , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Rizoma , Solventes/química
19.
Appl Microbiol Biotechnol ; 98(4): 1539-46, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24232832

RESUMO

In this study, after screening of eight fungal strains for their ability to produce calcium malate, it was found that Penicillium viticola 152 isolated from marine algae among them could produce the highest titer of calcium malate. At the same time, it was found that corn steep liquor (CSL) could stimulate calcium malate production and 0.5 % (v/v) CSL was the most suitable for calcium malate production. Under the optimal conditions, a titer of calcium malate in the supernatant was 132 g/l at flask level. During a 10-l fermentation, a titer of 168 g/l, a yield of 1.28 g/g of glucose, and a productivity of 1.75 g/l/h were reached within 96 h of the fermentation, and 93.4 % of the sugar was used for calcium malate production and cell growth, demonstrating that the titer, yield, and productivity of calcium malate by this fungal strain were very high and the fermentation period was very short. After analysis of the partially purified product with high-performance liquid chromatography, it was found that the main product was calcium malate. The results demonstrated that P. viticola 152 obtained in this study was the most suitable for developing a novel one-step fermentation process for calcium malate production from glucose on a large scale.


Assuntos
Meios de Cultura/química , Malatos/metabolismo , Penicillium/metabolismo , Zea mays/química , Reatores Biológicos/microbiologia , Biotecnologia/métodos , Meios de Cultura/farmacologia , Fermentação , Penicillium/efeitos dos fármacos
20.
Pak J Pharm Sci ; 27(5): 1359-62, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25176387

RESUMO

The accumulation of advanced glycationend products (AGE's) in the body, due to the non-enzymatic glycation of proteins is associated with several pathological conditions like aging and diabetes mellitus. Hence a plant having anti-glycation and anti-oxidation potentials may serve as therapeutic agent for diabetic complications and aging. In this study the anti-glycation and anti-oxidation properties of crude methanolic extracts of fruits of Capsicum frutescens and Curcuma longa were investigated. Among the two C. frutescens had more anti-glycation ability with a minimum inhibitory concentration (MIC50) of 90ßg/mLas compared to 324ßg/mL MIC50 of C. longa. Curcuma longa had the more anti-oxidation potential i.e. 35.01, 30.83 and 28.08% at 0.5mg, 0.25mg and 0.125mg respectively.


Assuntos
Antioxidantes/farmacologia , Capsicum , Curcuma , Complicações do Diabetes/prevenção & controle , Frutas , Hipoglicemiantes/farmacologia , Extratos Vegetais/farmacologia , Sequestradores de Radicais Livres/farmacologia
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