Biosynthesis of Graphene and Investigation of Antibacterial Activity of Graphene-parthenium hysterophorous Nanocomposite

Abstract There is a great interest to use carbon-based material like graphene and graphene oxide in biomedical applications due to its flexibility to be functionalized with bio-active molecules. Herein, graphene and graphene-based nanocomposites were biosynthesized by liquid-phase exfoliation of graphite using aqueous extract of Parthenium hysterophorous (P-H) as a surfactant. A set of five thin film samples of graphene was prepared from graphene suspension by vacuum filtration method. Samples were characterized by UV-vis spectroscopy, Raman spectroscopy, SEM, and XRD, which revealed successful synthesis of graphene. Graphene/P-H(G/P-H) nanocomposites comprising varied ratios of graphene and P-H were prepared and their antibacterial activity was investigated by agar well diffusion method. The experimental results indicated that G/P-H nanocomposite have higher antibacterial activity than graphene alone, and bioactivity of G/P-H nanocomposite was found to be controlled by the fraction of graphene in the composite.

Assessments on the catalytic and kinetic properties of beta-glucosidase isolated from a highly efficient antagonistic fungus Trichoderma harzianum / Avaliações das propriedades catalíticas e cinéticas da beta-glucosidase isoladas de um fungo antagonísta altamente eficiente Trichoderma harzianum

Due to the toxicity and inefficiency of chemical fungicides to control infestation of Macrophomina phaseolina (Tassi) Goid which causes charcoal rot in plants, a biotechnological approach using - glucosidase (EC.3.2.1) as the alternative bioactive ingredient in fungicide is hereby, proposed. The extracellular enzyme was isolated from a highly efficient fungal antagonist, Trichoderma harzianum T12. The highly similar molecular masses obtained using SDS-PAGE (96 kDa) and MALDI-TOF mass spectrometry (98.3 kDa) affirmed that the -glucosidase was purified to homogeneity. Consequently, optimum catalytic parameters that rendered the highest enzyme activity were found to be: 45°C, pH 7, inoculum size of 10 % (w/v), supplementation with metal ions Zn2+ and Mn2+ ions, and Tween 80. Addition of wheat bran and (NH4)2SO4 as carbon and nitrogen sources also improved enzyme activity. BLASTn showed the sequence of -glucosidase T12 was highly identical to other -glucosidases viz. T. harzianum strain IOC-3844 (99%), T. gamsii and T. virens bgl1 (86 %) as well as T. reesei strain SJVTR and T. viride strain AS 3.3711 (84 %). Kinetic assessment showed that -glucosidase T12 catalyzes hydrolytic activity is characterized by a Km of 0.79 mM and Vmax of 8.45 mM min-1 mg-1 protein, with a corresponding kcat of 10.69 s-1.

Devido à toxicidade e ineficiência dos fungicidas químicos para controlar a infestação de Macrophomina phaseolina (Tassi) Goid que causa o apodrecimento das plantas, uma abordagem biotecnológica usando - glicosidase (EC.3.2.1) como o ingrediente bioativo alternativo do fungicida é por este meio, proposto. A enzima extracelular foi isolada de um antagonista fúngico altamente eficiente, o Trichoderma harzianum T12. As massas moleculares altamente similares obtidas usando SDS-PAGE (96 kDa) e espectrometria de massa MALDI-TOF (98,3 kDa) afirmaram que a -glicosidase foi purificada até a homogeneidade. Consequentemente, os parâmetros catalíticos ótimos que apresentaram a maior atividade enzimática foram: 45°C, pH 7, tamanho do inóculo de 10% (p / v), suplementação com íons de metais Zn2+ e Mn2+, e Tween 80. Adição de farelo de trigo e (NH4) 2SO4 como fontes de carbono e nitrogênio também melhoraram a atividade enzimática. O BLASTn mostrou que a sequência da -glicosidase T12 era altamente idêntica a outras -glicosidase viz. A estirpe T. harzianum IOC-3844 (99%), T. gamsii e T. virens bgl1 (86%) assim como a estirpe T. reesei SJVTR e a estirpe T. viride AS 3.3711 (84%). A avaliação cinética mostrou que -glicosidase T12 catalisa a actividade hidrolítica caracterizada por um Km de 0,79 mM e Vmax de 8,45 mM min-1 mg-1 de proteína, com um correspondente kcat de 10,69 s-1.

Cypermethrin-induced Repeated-dose Immuno-toxicity in Oryctolagus Cuniculus: An Investigation into Pathology of Spleen and Blood

Background: Cypermethrin is a pyrethroid insecticide widely used in agriculture and medicines. Its toxicity effects on spleen and blood in male and female rabbits is studied in this research. Methods: Age- and weight-matched does/females (n=24) and bucks/males (n=24) of Japanese White rabbits were subjected to intraperitoneal cypermethrin administration @50, 100 and 150 mg.kg-1 b.wt. in groups B, C and D, respectively.  The experimental rabbit does and bucks were tested for hematology alterations after each of 5 CY-treatments, at days 1, 8, 15, 22 and 29.  One rabbit doe and one rabbit buck were sacrificed fortnightly (days 15, 29, 43, 57 and 71) to obtain spleen for histological studies. Results: CY-treated rabbit bucks developed anemia, leukopenia, neutropenia, monocytosis, eosinophilia and basocytopenia mostly in dose and time dependent manner.  In contrast, rabbit does show transient but significant leukocytosis, neutropenia, lymphopenia, monocytosis, eosinophilia and basophilia only in high dose group.  Moreover, spleen histology revealed congestion, depletion of white pulp with increased red pulp and hemosiderin deposition in CY treated rabbit bucks, but not rabbit does. Conclusions: This study concludes that immuno-toxicity by cypermethrin insecticide is not similar in male and female subjects.

Study on quality and efficacy of commercial tylosin and doxycycline products against local isolates of mycoplasma in broilers

The present study was conducted to investigate the quality and efficacy of commercially available preparations of tylosin and doxycycline available in the local market at Peshawar for poultry. In vitro and in vivo, tests were conducted to check the quality of these antimicrobial drugs. In vitro quality control test was performed by High performance liquid chromatographic [HPLC] and micro dilution method. In vivo, efficacy of the test drugs was checked in broilers infected with Mycoplasma gallisepticum. Results of HPLC indicated that test drug-2 contains doxycycline hydrochloride within specified limits but contain high quantity of active ingredient [Tylosin tartrate 120%]. Recovery percentage of test drugs [3, 4, 5] were below the pharmacopoeial limit, which contained low quantity of tylosin tartrate [85%, 87.5%, 85%] respectively however, percent recovery of doxycycline were in the appropriate limits. All the tested drugs were effective against Mycoplasma gallisepticum and showed minimum inhibitory concentration [MIC] at 1.9micro g/ml. The in vivo result indicated that all tested drugs decreased morbidity and mortality in infected chicks. The birds treated with test drugs [3 and 5] showed mortality of 9.5%, which was slightly higher than the other test groups. The current study suggested that there are incidences of substandard drugs in Pakistan and the drug regularity authorities should take strict actions against the manufacturing companies

Characterization Of A Novel Hydrolytic Enzyme Producing Thermophilic Bacterium Isolated From The Hot Spring Of Azad Kashmir-Pakistan

ABSTRACT A thermophilic bacterium (TP-2) was isolated from the Tatta Pani hot spring in Azad Kashmir and was characterized using phenotypic and genotypic characters. The strain developed cream colored, round, smooth, flat and slimy colonies while the cells were Gram positive rods that ranged in size from about 2.1-3.6 μm to 0.2-0.3 μm in width. Sequence analysis of its 16S rRNA gene showed that isolate TP-2 had 89% homology with Geobacillus debilis. It grew within pH range of 5.5 to 8.5 with optimum growth at pH 7.0. The isolate showed optimum growth at 65ºC and gave positive results for gelatin hydrolysis (GEL), ortho nitrophenyl-β-D-galactopyranosidase (ONPG), and nitrate production and produced acid from sucrose, glucose and maltose. It utilized glucose, fructose, maltose, lactose, sucrose, xylan, starch, filter paper and carboxymethylcellulose as sole carbon source. Isolate TP-2 produced significant amount of industrially important enzymes i.e. extracellular α-amylase, CMCase, FPase, Xylanase, Protease and Lipase and intracellular CMCase and FPase.

Antibacterial activity of herbal extracts against multi-drug resistant Escherichia coli recovered from retail chicken meat

Increasing incidence rate of multiple drug resistance in Escherichia coli [E. coli] due to extensive uses of antibiotics is a serious challenge to disease treatment. Contaminated retail chicken meat is one of the major sources of spread of multi drug resistant [MDR] E. coli. Current study has been conducted to study the prevalence of MDR E. coli in retail chicken meat samples from Lahore city of Pakistan and it was found that 73.86% of E. coli isolates have MDR pattern. In vitro evaluation of antibacterial activity of crude ethanolic extracts of six herbs against MDR E. coli phenotypes has revealed that clove and cinnamon have maximum zones of inhibition as compared to other herbal extracts. Mint and coriander gave the intermediate results while garlic and kalonji showed the least antibacterial activity against the MDR E. coli phenotypes using the agar well diffusion technique. Average Minimum Inhibitory Concentrations [MICs] for clove, mint, cinnamon, coriander, kalonji and garlic extracts were 1.15, 1.38, 0.5, 1.99, 2.41, 8.60mg/mL respectively using the broth micro dilution method. The results obtained in present study were revealed that crude ethanol extracts of selected herbs have had significant antibacterial activity. Hence they can be used as promising alternatives of antimicrobials against MDR E. coli species and can be used for cooked food preservation

Isolation identification and control of vancomycin resistant Staphylococcus aureus

PakisVancomycin resistant Staphylococcus aureus [VRSA] has been reported from many parts of the world including Asian countries. Hence, main objective of study was to evaluate the possible occurrence of VRSA in hospitals of Lahore city and to ensure the effectiveness of various substitute therapeutic options. A total of 150 samples of pus/wounds were collected from three hospitals of the city and VRSA were isolated and confirmed through recommended method of Clinical and Laboratory St and ards Institute. Out of 51 [49.04%] methicillin resistant S.aureus [MRSA] isolates, 5 [9.8%] were found resistant to vancomycin. Minimum inhibitory concentration [MIC] of Linezolid [LZD], Moxifloxacin [MFX] and Clindamycin [CD] were calculated against VRSA isolates by broth microdilution test. All 5 [100%] isolates were susceptible to Linezolid and Clindamycin, while 4 [80%] were susceptible to Moxifloxacin. Ethanolic extracts of Turmeric, Mint, Cori and er, Garlic, Kalonji, Cinnamon and Cloves illustrate average MIC values of 140.8µg/ml, 563.2µg/ml, 486.4µg/ml, 614.4µg/ml, 409.6µg/ml, 281.6µg/ml and 64µg/ml, respectively against 5 VRSA strains. Concentration dependent increase in growth inhibition zones of ethanolic plant extract was recorded by agar well diffusion test. This study was helpful to find out the effective antibiotic against VRSA. Plant extracts encompass anti-staphylococcal activity and this finding dem and s necessity of further exploration of potential found in these natural herb.

Spatial Trend of Foot and Mouth Disease Virus (FMDV) Serotypes in Cattle and Buffaloes, Pakistan / 中国病毒学·英文版

The present study describes the frequency of Foot and Mouth Disease (FMD) virus serotypes (O,A and Asia-1) in major regions (all provinces) of Pakistan using Indirect Sandwich ELISA.Also,spatial distribution of various FMD serotypes and their comparison is discussed.A total of 590 samples (Epithelial tissue) have been analyzed during a period of five years (2005-2009).Out of 590 samples,180 were found positive,giving an overall confirmation of FMDV about 33.2 ％.Of the prevalent serotypes,FMDV ‘O’ serotype caused most outbreaks (20.7 ％),followed by serotype A (6.6 ％) and serotype Asia-1 (4.6 ％) while there was no positive case oftype ‘C’.The study clearly showed that the disease was more frequent in the agro-climatic zones than in hilly areas.Based on the data of 590 samples (＞50 outbreaks),the overall prevalence of FMDV in cattle and buffaloes in Pakistan was 33.2 ％,while in cattle alone,it was 37.1％,higher than in buffalo (28.7 ％).There were eight cases of mixed serotypes infection,indicating the presence of endemic state of disease.Another significant feature was the change over time.In phase-I (2005-2007),there was an overall prevalence of 29.4 ％,while the occurrence of the serotype O,A and Asia-1 was 20.4 ％,2.9 ％ and 4.7 ％,respectively.During phase-II (2008-2009),the overall prevalence was 59.21％,while those of serotype O,A and Asia-1 were 22.4 ％,31.6 ％ and 4.0 ％,respectively.This clearly indicated a shift from serotype O to A,which may help to explain the occurrence of more severe outbreaks,despite vaccination.