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文章
Jiraporn Nikomtat, Puttinan Meepowpan and Yingmanee Tragoolpua*
Abstract: The methanol and dichloromethane extracts of Inula cappa (Ham. ex D. Don) DC. were evaluated for inhibition of herpes simplex virus infection. Higher anti- herpes simplex virus (HSV) activity of I. cappa methanol extract was observed comparing with I. cappa dichloromethane extract since more than 50% of the virus was inhibited by I. cappa methanol extract and 50% effective doses of I. cappa methanol extract on HSV-1and HSV-2 were 720.1±32.7 and 529.2±5.2 µg/ml respectively. However, when the virus particles were treated with I. cappa dichloromethane and I. cappa methanol extracts, both HSV-1 and HSV-2 particles were directly inactivated to negligible amount within 1 - 2 h. More than 50% interference on blocking of HSV attachment and penetration was observed after treatment the virus with I. cappa methanol extract. Moreover, within 30 h, the effective inhibitory activity of I. cappa methanol extract on HSV replication was higher than that of the I. cappa dichloromethane extract. Both extracts had potent activities in reducing viral deoxyribonucleic acid (DNA) synthesis since HSV DNA after treatment with the extracts were 1.3-2 fold less than HSV DNA control after determination by real time polymerase chain reaction and approximately 45 kilodalton viral proteins were clearly diminished after treatment with I. cappa methanol extract. Therefore, methanol extract of I. cappa is a potent inhibitor of herpes simplex virus infection in vitro.[...] Read More.
Keywords: Anti-viral activity, Inula cappa, plant extract, herpes simplex virus.
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文章
Parvaneh Jafarei* and Maryam Tajabadi Ebrahimi
Abstract: Lactic acid bacteria (LAB) are one of the most applied bacteria in the production of fermented foods, from dairy to fruits and vegetables products. They make food durable, improve food safety, flavor, and texture as well as to enhance food physiological and hygienic value due to the presence of viable cells and valuable. Besides, products obtained by LAB fermentation processes are of special importance for functional foods such as probiotics. Lactobacillus acidophilus is the best well-known species of this Lactobacillus complex in LAB group and exist in the gastrointestinal tracts of humans and animals. In fermented food, the metabolic activity of this microorganism results in production of flavor, and aroma that cause organoleptic properties of fermented foods and inhibits foods spoilage. L. acidophilus effect on modulation of host immunity is proved by clinical evidence but molecular and cellular mechanisms of these effects are not completely clear. Despite the increasing application of this bacterium, little is known about its effects on the gut community, host physiology and immunity. The molecular mechanisms by which L. acidophilus exert these effects are not clearly understood. In this regard, recognition of cell structures and the genomic base of this bacterium could be useful. In this paper we try to gather all the information that exists about this bacterium.[...] Read More.
Keywords: Lactobacillus acidophilus, structure, fermented food, probiotic.
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文章
Jia-Ying Zhu, Song Yang, Qin-Wen Li and Yong-He Li*
Abstract: Microsatellite as one of the most popular molecular markers provides a useful tool for population genetic structure analysis in insects. But few microsatellite loci have been developed for Lepidoptera. Here we isolated and characterized 9 polymorphic microsatellite loci in Rhyacionia leptotubula (Lepidoptera: Tortricidae). The number of alleles of these loci ranged from 2 to 11. Observed and expected heterozygosities ranged from 0.0000 to 0.5294 and from 0.3905 to 0.8719, respectively. Seven loci show significant Hardy-Weinberg deviations. These loci could provide insight into population genetic structure and dispersal patterns of R. leptotubula.[...] Read More.
Keywords: Rhyacionia leptotubula, microsatellite, population genetics, Lepidoptera.
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Xiao Xiao, Jingling Zhang, Quanyi Zhang, Li Wang, Yafang Tan, Zhaobiao Guo, Ruifu Yang, Jingfu Qiu and Dongsheng Zhou*
Abstract: Due to the production of abundant capsular polysaccharides and or exopolysaccharides, some bacteria form mucoid and opaque colonies on solid agar medium. Polysaccharides interfere with the isolation and characterization of DNA. Extraction of polysaccharide-free DNA from the mucoid bacteria is required for genetic and biochemical studies. In this study, mucoid Vibrio parahaemolyticus and Klebsiella pneumonia were used as model organisms for comparing the effectiveness of two DNA extraction methods. The two methods were proved reproducible and cost-effective for extracting high-purity genome DNA from mucoid bacteria for further applications.[...] Read More.
Keywords: Mucoid bacteria, Vibrio parahaemolyticus, Klebsiella pneumonia, DNA isolation, polysaccharides.
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文章
Yi Zhan, Quan Xu, Hongxia Liu, Yunpeng Wang* and Jianhua Guo
Abstract: The influence of bacterial suspension concentration on biocontrol efficacies and storage stabilities of three biocontrol agents, including BACILLUS CEREUS AR156, PANTOEA ANANATIS YT11 and PSEUDOMONAS FLUORESCENS ABc9, were studied. The results indicated that biocontrol efficacy and storage stability did not increase along with the enhancement of the concentration of biocontrol agents, and 109 CFU ml-1 of the strain P. FLUORESCENS ABc9, 108 CFU ml-1 of B. CEREUS AR156 and 108 CFU ml-1 of P. ANANATIS YT11 provided the best biocontrol efficacy as 63.06, 49.55 and 52.25% respectively, and the most suitable concentration of the biocontrol agents for preservation ranged from 108 to 109 CFU ml-1.[...] Read More.
Keywords: Biological control, strain concentration, biocontrol efficacy, storage viability.
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文章
Rong Chen, Xiaopu Yin, Chunna Yu, Qiuyan Wang, Xiaori Zhan and Tian Xie*
Abstract: The gene encoding a thermophilic group 3 alcohol dehydrogenase from Thermotoga lettingae TMO was cloned and over-expressed in Escherichia coli. The full-length DNA sequence of TlADH was 1086-bp encoding a polypeptide of 361 amino acids. Comparative and bioinformatic analysis revealed that TlADH showed high similarity to group 3 ADHs from thermophilic and mesophilic alcohol dehydrogenases, but relatively highest similarity to T. maritime 1, 3-propanediol dehydrogenase. The optimal pH-values of butanol oxidation and butylaldehyde reduction of TlADH were 11.9 and 6.0, respectively. Kinetic parameters of the enzymes showed TlADH preferred NADP+ to NAD+ as a cofactor. TlADH can catalyze a range of primary alcohols oxidation, while it was inactive towards branched-chain alcohols and cyclitol. TlADH also can reduce aldehydes to corresponding alcohols, including aliphatic and aromatic aldehydes. It showed higher activity of aldehyde reduction than that of alcohol oxidation that may be relative to reactive aldehyde detoxification in cell metabolism. In the case of external ions addition we found a 5.23-fold increase in reaction activity by the adding of 1 mM MnCl2. T. lettinga ADH was cloned and overproduced in a mesophilic heterologous expression system, and the recombinant enzyme was characterized. It will be helpful to understand more about the physiological role of group 3 alcohol dehydrogenase.[...] Read More.
Keywords: Group 3 ADH, bioinformatic analysis, recombinant expression, thermophilic, catalytic properties.
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文章
A.  K. Al-Ghamdi, S. M. A. Abdelmalek* A. M. Ashshi, H. Faidah, H. Shukri  and A. A. Jiman-Fatani
Abstract: This study aims at investigating the status of bacterial contamination of four daily used objects, computer keyboards, computer mice, elevator buttons and shopping carts handles. A total of 400 samples were collected from 4 different objects; 100 from each. Samples were collected from different places (offices, internet cafes, homes, buildings and supermarkets) in the city of Jeddah, Saudi Arabia. 95.5% of the total samples collected were contaminated with mixed bacterial growth. Coagulase-negative staphylococci dominated the isolates. The second most common bacterial growth in all specimens was Gram-positive bacilli. Potential pathogens isolated from all specimens were: Staphylococcus aureus, Pseudomonas spp. and Gram negative bacilli. Results indicate that internet café computer keyboards and mice showed 100% contamination in comparison with other objects. The presence of pathogenic and commensal bacteria on the four objects indicates that they might act as environmental vehicles for the transmission of potentially pathogenic bacteria.[...] Read More.
Keywords: Bacterial contamination, computers, public surfaces.
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文章
Efuntoye M. O.*, Bakare A. A. and Sowunmi A. A.
Abstract: A total of 34 isolates of bacteria, 20 Staphylococus aureus and 14 Clostridium perfringens from leachate samples, were investigated for virulence factors and antibiotic resistance. Majority (>70%) of the isolates produced enterotoxins. Many of the S. aureus isolates tested positive for deoxyribonuclease, haemolysins and slime production. Staphylococcal enterotoxin A (SEA) was the predominant enterotoxin produced by the S. aureus. None of the S. aureus was resistant to ciprofloxacin, novobiocin and vancomycin. Six isolates were resistant to methicillin and majority of them were resistant to penicillin, ampicillin and bacitracin. Eleven (78.6%) of the C. perfringens isolates produced enterotoxin and were also beta haemolytic. Except for one strain each of C. perfringens which were resistant to penicillin and ampicillin-sulbaltam respectively, all others were susceptible to the antibiotics tested. The presence of several of the virulence traits investigated and resistance to commonly used antibiotics in many of the S. aureus and C. perfringens tested raises concern about their dissemination through leachate to the environment. The accumulation of leachate and possible contamination of surface and groundwater sources also points out its potential risk for public health. There is need for some measures to properly manage waste and consequently reduce surface and groundwater contamination through leachate percolation.[...] Read More.
Keywords: Virulence factor, landfill leachate, antibiotic resistance, Staphylococcus aureus, Clostridium perfringens, health impact.
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文章
Shahzad Akbar Khan*, Tarique Hussain, Muhammad Akhtar Qureshi, Gulzar Ahmed, Sarfaraz Ali Fazlani, Ijaz Ahmed and Farhan Anwar Khan
Abstract: Indirect Haemaglutination test is a reliable quantitative serological test for measuring antibodies against angara disease. The etiological agent contained in the liver of affected chick did not directly haemaglutinate erythrocyte of chickens. The antibody titre measured through IHA varied from 1:8-1: 128, in the sera (samples) of experimentally infected chickens at days 7, 14 and 21 post vaccination.[...] Read More.
Keywords: Haemagglutination, titre, sera, angara disease.
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文章
Ivana D. Radojević*, Milan S. Stanković, Olgica D. Stefanović, Marina D. Topuzović, Ljiljana R. Čomić and  Aleksandar M. Ostojić
Abstract: In vitro antifungal activity of methanol, acetone and ethyl-acetate extracts from Equisetum telmateia Ehrh., Allium flavum L., Sedum acre L., Sideritis montana L., Marubium peregrinum L. and Xeranthemum anuum L. grown in Serbia, were investigated by microdilution method. Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) have been determined. Testing was conducted against four Aspergillus species - A. flavus, A. fumigatus, A. niger and A. restrictus. All statistical analyses were performed using SPSS package. The tested extracts showed significant antifungal activity against A. restrictus and moderate activity against other Aspergillus spp. The best results showed ethyl acetate extract of S. montana, X. anuum and S. acre.[...] Read More.
Keywords: Antifungal activity, plant extracts, Aspergillus spp.
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