MOSP - Macao Scientific Publishers

文章

Production and characterization of cellulolytic enzymes by Pleurotus florida

Meenakshi Goyal* and Giridhar Soni

Abstract: Three Pleurotus spp., Pleurotus florida, Pleurotus ostreatus and Pleurotus sajar-caju, were screened for cellulolytic enzyme production under submerged fermentation conditions. Of these, P. florida, was studied for optimizing medium composition, incubation period, initial pH and incubation temperature to maximize cellulolytic enzyme production. Malt extract at 0.5%, 12 day of incubation period and 1% CMC as carbon source supported maximum production of cellulases. The optimum temperature and pH for maximum production of enzymes were 35 to 40°C and 5.0 for exo-and endoglucanases and 30°C and 4.5 for b- glucosidase.[...] Read More.

Keywords: Endoglucanase, exoglucanase, fermentation conditions, b-glucosidase, medium composition.

Full text

Download：894

文章

A note on hierarchy evolutionary game

Xiao-xing Liu

Abstract: Stochastic evolutionary game dynamics in hierarchy are very popular in economics and in management sciences. This study extends the model of stochastic evolutionary game dynamics. This paper highlights hierarchy selection model and we show that the hierarchy selection games are more stable without structures in this paper. Furthermore, an example in industrial organization is given to rationally explain the theory in this work.[...] Read More.

Keywords: Fitness, fixation probability, invasion, game theory, economics, hierarchy, evolutionary game.

Full text

Download：852

文章

A new cost-effective staining method for rapid identification of Cryptococcus

Rugen Wan, Maofeng Wang*, Sheng Zhao, Guogang Li, Yangxiao Zhou, Jiajun Li and Jinkan Du

Abstract: Cryptococcosis is a life-threatening fungal disease that usually presents as an opportunist infection in immunocompromised hosts, and Cryptococcus neoformans is the major opportunistic pathogen of cryptococcosis. Rapid diagnosis of C. neoformans and other opportunistic Cryptococcus pathogens is required to meet the clinical need for immediate treatment. Historically, negative staining with India ink has been used to identify Cryptococcus. Another staining method utilizes Alcian blue, a dye that reacts selectively with C. neoformans, but not other Cryptococcus species. To overcome these limitations, we developed a new staining method for rapid identification of Cryptococcus using a novel, patent pending staining reagent for clinical laboratory diagnosis. Cryptococci stained with this new reagent can be conveniently counted directly via bench-top light microscopy. We also compared our novel stain with India ink and Alcian blue. Our results demonstrated that the new staining technique was superior to India ink stain for the rapid identification of Cryptococcus in clinical (and clinically mimicking) samples. Our stable and cost-effective staining reagent specifically stained Cryptococcus, highlighting its clinical applicability, particularly in developing countries due to its low cost.[...] Read More.

Keywords: Cryptococcus, cryptococcosis, specific staining, India ink staining, rapid identification.

Full text

Download：890

文章

Does borna disease virus (BDV) have a role in the etiopathogenesis of schizophrenia?

Karakose A. R., Yuksel P., Turan N., Ziver T. , Sariba S., Nihat Alpay, Balcioglu I., Aslan M., Helps C. R., Yilmaz H. and Kocazeybek B.*

Abstract: In human, certain serological and molecular trials estimated an association between psychiatric diseases, particularly schizophrenia, mood disorders and borna disease virus (BDV). The purpose of this study was to investigate whether BDV has association with etiopathogenesis of schizophrenia. A total of 207 patients who were diagnosed with residual schizophrenia and 51 patient control grop with 134 healthy control group were included in the study. RNA of borna disease virus (BDV p24 and p40) in the peripheral blood was investigated by using real-time RT-PCR. A highly significant difference was detected between patient and healthy control group cases in terms of BDV IgG seropositivity (p[...] Read More.

Keywords: Borna disease virus, schizophrenia, ELISA.

Full text

Download：890

文章

A recombinant E0 gene of bovine viral diarrhea virus protects against challenge with bovine viral diarrhea virus of sika deer

Yugang Gao, Yajun Wang, Rui Du, Quankai Wang, Pengju Zhang*, Shuzhi Wang and Lianxue Zhang*

Abstract: Eukaryotic expression plasmid (PVAX 1/E0) of E0 gene was constructed from an isolated strain of bovine viral diarrhea virus (BVDV) from sika deer and transfected into the BHK-21 cells to detect E0 gene transcription expression level and protein expression level. It was found that E0 gene could express in BHK-21 cells by RT-PCR and ELESA results. The humoral and cellular immune response levels were detected in rabbits immunized with PAVX1/E0 and inactivated vaccine by ELESA technology, which reached the peak after 42 days immunization and PVAX1/E0 immune rabbits could produce specific higher cells immune responses level in comparison to inactivated vaccine group. This is the first report demonstrating and “immunogenicity” of BVDV E0 gene on “sika deer”, indicating a new vaccine target for BVDV.[...] Read More.

Keywords: Sika deer, bovine viral diarrhea virus, E0 gene, eukaryotic expression, immune response.

Full text

Download：844

文章

Production of recombinant cellulase enzyme from Pleurotus ostreatus (Jacq.) P. Kumm. (type NRRL-0366)

Ayman S. Daba, Ghada A. Youssef*, Sanaa S. Kabeil and Elsayed E. Hafez

Abstract: Successful utilization of Pleurotus ostreatus (Jacq.) P. Kumm. (type NRRL-0366) mushroom as a type of edible locally isolated mushroom in Egypt at the Mushroom Research Center (Mubarak City for Scientific Research and Technology Applications), to produce extensive hydrolyzing cellulase complex enzymes. This hydrolysis was approached in submerged culture supplemented with avicel PH101 as a substrate for endo-,exoglucanase production. The avicel concentration 6% yielded the maximum enzyme activities (2.46, 1.80 U/ml) for both endo-and exoglucanase activities on basal medium at 27°C, initial pH value of 5.5 for 12 days on rotary shaker (180 rpm) incubation period. Cellulase enzyme was amplified using specific PCR and the amplicone was cloned using TOPO TA cloning vector. The cellulolytic activity of the recombinant protein was examined and high activity was obtained compared with the standard ones. The avicel was used as a sole carbon source in the fermentation medium and the results revealed that, avicel induced the cellulolytic activity of the examined organism compared with those grown on medium deficient of avicel.[...] Read More.

Keywords: Pleurotus ostreatus, mushroom, avicel, recombinant cellulolytic enzymes.

Full text

Download：834

文章

Screening and induction of laccase activity in fungal species and its application in dye decolorization

Vaidyanathan Vinoth Kumar, Selvaraj Dinesh Kirupha, Premkumar Periyaraman and Subramanian Sivanesan*

Abstract: A great deal of works has been carried out assessing dye-decolorization capabilities of fungi, but only few species were investigated. In this present study, ten fungal species were screened for laccase activity by indicator plate method, of which five species were found to be laccase-positive. Laccase activity varied during growth and maximal laccase activity was observed during the 9th day, except for Agaricus bisporus. Pleurotus ostreatus gave the highest laccase activities, showing average value around 570 U/L, which were higher than other strains. Addition of 1 mM copper sulphate induced the laccase production efficiently by 60 to 80%, while veratryl and benzyl alcohol induced laccase production in all the laccase positive species except for A. bisporus. Constitutive expression of laccase was observed in F. solani in the presence of copper sulphate. In addition, the extracellular laccase from the P. ostreatus could decolorize reactive dyes, which suggests the potential application of laccase in textile effluent treatment.[...] Read More.

Keywords: Dyes, decolorization, inducer, laccase, Pleurotus, textile.

Full text

Download：974

文章

Variability in antimicrobial activity of latex from two varieties of Ficus carica

Houda Lazreg Aref*, Bel Hadj Salah Karima, Abdelwaheb Fekih, Rachid Chemli, Massoud Mars, Mahjoub Aouni, Jean Pierre Chaumon and Khaled Said

Abstract: Fig latex has been a typical component in the health -promoting Mediterranean diet for millennia. To study its potential constituents, two varieties differing in color of fruit [Bidhi Bither: (BB); Kahli Bither: (KB)] and their growth area were analyzed for their organic extracts against sixteen microbes. The capacity of extracts was evaluated based on the inhibition zone, using the disc-diffusion assay, minimal inhibition concentration (MIC) for bacteria and yeasts, the method of calculating the inhibition percentage (I%) and Agar punched wells method for fungi, respectively. Extracts of (BB1) variety from Chott Meriam showed the highest antimicrobial activities against the studied microorganisms when compared to (KB) variety and those from Mahdia. Ethyl acetate extracts had inhibition effect on the multiplication of Enterococcus faecalis, Citobacter freundii, Pseudomonas aeruginosa, Proteus mirabilis and Escherchia coli. For the opportunist pathogenic yeasts, ethyl acetate and chloroformic fractions showed a very strong inhibition (100%) and an MIC of 0.082 and 1.25 µg/ml for (BB) and (KB), respectively, while ethanolic fraction had a total inhibition against Candida albicans, Candida glabrata, Candida krusei and Candida parapsilosis. Microsporum canis was strongly inhibited with ethanolic extract (75%) and totally with ethyl acetate extract at a concentration of 500 µg/ml.[...] Read More.

Keywords: Ficus carica, latex, organic extracts, fungi, yeasts, bacteria, antimicrobial activity.

Full text

Download：892

文章

Effect of some culture substrates (date-palm peat, cocopeat and perlite) on some growing indices and nutrient elements uptake in greenhouse tomato

Ahmad Mohammadi Ghehsareh*, Hassan Borji and Mehrdad Jafarpour

Abstract: In recent years, a wide range of soilless culture techniques have been developed and commercially introduced for intensive production of horticultural crops, particularly in greenhouses. Reasons for replacing soils as growing media arise from plant protection problems with soil-borne pathogens and environmental regulations against groundwater pollution with nitrate and pesticides. The aim of this study was to compare some growing indexes of greenhouse tomato that were cultivated in some substrates, such as perlite, date-palm peat and coco peat. The research was conducted in a completely randomized design with 6 replications. The treatments were coco peat + perlite (v/v=50%)‚ date-palm peat + perlite (v/v=50%)‚ perlite (100%) and date-palm peat(100%). Papadopolus formula was used for nutrient solution during plant growth with fertigation method. Also temperature, humidity and irrigation rate was constant for all treatments. Comparison of means showed that the media had no significant effect on concentration of nutrient elements in fruit such as N, P, K and yield in all treatments. Minimum and maximum amount of fruits yield was in date-palm peat and perlite treatments respectively. That had no significant difference with other treatments. Higher amount of total soluble solids (TSS) related to coco peat + perlite treatment that has not any significant difference with date-palm peat + perlite, perlite and date-palm peat treatments. Also, culture substrates had no significant difference on the amount of ascorbic acid. The results showed that date-palm peat is an appropriate media for soilless culture with suitable physical and chemical properties, availability and low cost. Therefore, it can be a new substrate that is introduced for replacing other media. Key word: Soilless, substrate, date-palm peat, total soluble solids, ascorbic acid.[...] Read More.

Keywords: Soilless, substrate, date-palm peat, total soluble solids, ascorbic acid.

Full text

Download：850

文章

Antibacterial activity of ZnO nanoparticle on gram-positive and gram-negative bacteria

Zarrindokht Emami-Karvani* and Pegah Chehrazi

Abstract: The aim of the present study is to determine the antimicrobial activity of ZnO nanoparticles against Gram-negative and Gram-positive bacteria. Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were used as test microorganisms. The effects of particle size and concentration on the antibacterial activity of ZnO nanoparticles was studied using bacteriological tests such as disc and well diffusion agar methods, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). These tests were performed in nutrient broth and nutrient agar following standard methods. In addition, the effect of different concentrations of ZnO nanoparticles on the growth of E. coli and S. aureus was measured with respect of time. The minimum inhibitory concentration was determined using seven different concentrations of ZnO nanoparticles including 16, 8, 4, 2, 1 and 0.5 mg/ml. The MIC value for E. coli and S. aureus was 1 and 0.5 mg/ml, respectively. The results showed that ZnO nanoparticles have antibacterial inhibition zone of 29 and 19 mm at the concentration of 10 mg/ml against E. coli and S. aureus, respectively. Gram-negative bacteria seemed to be more resistant to ZnO nanoparticles than Gram-positive bacteria. It was found that the antibacterial activity of ZnO nanoparticles increased with decreasing particle size and increasing powder concentration. The antibacterial effect of ZnO nanoparticles was time dependent and takes effect gradually. ZnO bulk powder showed no significant antibacterial activity. Key word: ZnO nanoparticle, Escherichia coli, Staphylococcus aureus, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC).[...] Read More.

Keywords: ZnO nanoparticle, Escherichia coli, Staphylococcus aureus, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC).

Full text

Download：814

Search Filter