MOSP - Macao Scientific Publishers

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A method for the determination of tannase activity based on gallic acid measurement by high performance liquid chromatography (HPLC)

Nalan Yilmaz Sariözlü*, Erdoğan Çakir, Merih Kivanç and Muzaffer Tunçel

Abstract: A new high performance liquid chromatography (HPLC) method was developed based on an indirect determination of tannase activity through gallic acid measurement using paracetamol as an internal standard. The separation was performed on a C18 column using a mobile phase consisting of aqueous formic acid solution (1%) and methanol (85:15; v/v) pumped at 1 ml min-1. Samples (10 μl) were injected and signals were detected at 254 nm. Repeatability was 0.81 and 1.28 for peak normalization values of gallic acid (4.16 x 10-5 M) and internal standard (2.02 x 10-5 M). A good linearity was shown in the range of 1.04 x 10-5 to 8.32 x 10-5 M. Limit of detection (LOD) and limit of quantification (LOQ) values were calculated to be 2.2 x 10-6 M and 6.6 x 10-6 M, respectively. The applicability of the method was tested using Penicillium spinulosum which produces tannase. The method was highly sensitive, accurate, reliable, and repeatable and at the same time it is applicable to both pure and crude enzyme.[...] Read More.

Keywords: Tannase activity, gallic acid, tannic acid, high performance liquid chromatography, enzyme activity, validation.

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Antibacterial activity of Moringa oleifera and Moringa stenopetala methanol and n-hexane seed extracts on bacteria implicated in water borne diseases

Atieno Walter*, Wagai Samuel, Arama Peter and Ogur Joseph

Abstract: The anti-bacterial activity of methanol and n-hexane extracts of Moringa oleifera and Moringa stenopetala seeds was conducted on 3 bacterial species (Salmonella typhii, Vibrio cholerae and Escherichia coli) which normally cause water borne diseases. The paper disc diffusion method was used with treatments arranged in a completely randomized design and replicated four times. The highest inhibitions were observed at dilutions of 20, 5 and 40% for M. oleifera and M. stenopetala methanol extracts on E. coli, S. typhi and V. cholerae respectively. The n-hexane extract of both M. oleifera and M. stenopetala had a higher inhibition on S. typhii than V. cholerae and E. coli. The results of this study showed that M. oleifera and M. stenopetala had a degree of antibacterial properties especially in low doses.[...] Read More.

Keywords: Moringa oleifera, Moringa stenopetala, methanol and n-hexane extracts, inhibition, Salmonella typhii, Vibrio cholera, Escherichia coli, Kenya.

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Some cellular immune components and C-reactive protein monitoring in female handball players during a competitive period

Tarik Sevindi, Serkan Hazar, Serkan Ibi and Kadir Gökdemir

Abstract: The aim of the study was to determine the effect of the competitive period training on leukocytes, some leukocyte subgroups and C -reactive protein (CRP) in sportswomen playing in the professional handball league. The average age of the group was 20.6 ± 3.37 years, height average was 163 ± 6.30 cm, weight average was 58.73 ± 4.92 kg. Blood samples were taken before and after the training period of the competition. Subjects rested for 48 h until taking blood samples. Subsequently, leukocytes, some leukocyte subgroups and CRP were determined. Leukocytes and leukocyte subgroups were determined using a Roche Sismex 2000XL device. CRP was determined using Beckman immunochemistry systems in-vitro diagnostic kits and nephelometric methods (Beckman Coulter Array 360 System, USA). Statistical analysis was performed using a paired t-test. p values[...] Read More.

Keywords: Training, immune component, C- reactive protein, female athlete.

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Effect of salinity on free living - diazotroph and total bacterial populations of two saline soils

Azam Moradi, Arezoo Tahmourespour*, Mehran Hoodaji and Farhad Khorsandi

Abstract: Salinization of soil is a serious problem and is increasing steadily in many parts of the world. Recently, soil biotechnology application can improve the potential of saline soils land use in agriculture. The aim of this research was determining the salinity effect on free-living diazotroph and total bacterial populations in two saline soils. Soil samples with salinity of 35 and 70 dS/m selected. The heterotrophic and free-living diazotrophic bacterial populations were counted on nutrient agar and free-nitrogen medium. The salinity effect on population of each soil was determined on same media supplemented with 0.44 and 1.02 M NaCl (equal with EC 35 and 70 dS/m of each soil). The results showed that, the free- living diazotrophic and total heterotrophic bacterial populations in soil sample 1 was significantly (P < 0.05) more than soil sample 2. Also the heterotrophic and diazotrophic bacterial population in each soil sample were significantly less in the presence of salt. Soil salinity is a stress factor relating to microbial selection process and can reduce bacterial diversity and control microbial abundance, composition and functions. Use of soil halotolerant or halophyl bacterial strains which can either fix atmospheric nitrogen will be environmentally begin approach for nutrient management and ecosystem function for saline soils.[...] Read More.

Keywords: Salinity, bacterial population, diazotrophic, heterotrophic.

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Isolation and identification of endophytic bacterium W4 against tomato Botrytis cinerea and antagonistic activity stability

Cong-Jun Yang, Xin-Gang Zhang, Guan-Ying Shi, Hao-Yu Zhao, Long Chen, Ke Tao,* and Tai-Ping Hou,*

Abstract: Of the 72 endophytic bacteria isolated from healthy tomato stems and leaves from field-grown plants, the strain W4 gave strongly inhibitory effect on Botrytis cinerea Pers, with the inhibition rate 78% in dual culture assay and 100% using fermentation filtrate diluted 20 times. Based on morphological, physiological and biochemical properties, 16S rDNA gene sequences and Biolog system analysis, the isolate W4 was identified and named as Brevibacillus brevis W4. The activity determination demonstrated that the antagonistic effect of W4 fermentation filtrate on B. cinerea was fairly stable to temperature, pH, ultraviolet light. Only heated at 90°C for 30 min or at 100°C or above for 10 min, the inhibitory effect was significantly reduced. The inhibitory rate remained above 90% at pH 2-11 and above 95% under ultraviolet light radiation for 5-240 min. These stability characteristics of antagonistic activity were conducive to future applications in the field.[...] Read More.

Keywords: Botrytis cinerea, Brevibacillus brevis W4, endophytic bacteria, antagonistic activity.

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Antibiotic resistance in Escherichia coli strains isolated from water springs in Al-Ahsa Region

Abdullah M. Alzahrani and Youssuf A. Gherbawy,*

Abstract: In Saudi Arabia, water resources are largely limited to groundwater, which is used both for drinking and agriculture. There is no surface water except for a few oases and no permanent streams. The contamination of this source possibly through wastewater, agriculture activities and wild birds as well as amphibians and reptiles that have access to wells and springs. Twenty six strains of Escherichia coli, isolated from water springs in Al-Ahsa Region of Saudi Arabia were analyzed for their antimicrobial susceptibility. Fifteen strains, representing 57.74% of the total twenty six strains, showed multidrug resistance phenotypes. RAPD -PCR with two random primers produced different DNA fingerprinting profiles with varied number of bands. The dendrogram obtained from the RAPD-PCR results discriminated the isolates into 26 single isolates and 3 clusters at the level of 40% similarity.[...] Read More.

Keywords: Escherichia coli, antibiotic resistance, water springs, RAPD-PCR.

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Actinopolyspora egyptensis sp. nov., a new halophilic actinomycete

Wael N. Hozzein,* and Michael Goodfellow

Abstract: A halophilic actinomycete, designated HT371T, was isolated from a soil sample collected from the shore of the salty Lake Qaroun, Egypt, and was the subject of a polyphasic study. Analysis of 16S rRNA indicated that the isolate belonged to the genus Actinopolyspora and constituted a separate clade in the Actinopolyspora 16S rRNA gene tree with similarity values of 96.5 and 96.2% with Actinopolyspora halophila DSM43834T and Actinopolyspora mortivallis DSM44261T, respectively. Isolate HT371T had chemotaxonomic and morphological properties consistent with its classification in the genus Actinopolyspora and could grow on agar plates at NaCl concentrations of up to 25% (w/v). The isolate was readily differentiated from the type strains of genus Actinopolyspora using a range of phenotypic characters. On the basis of polyphasic evidence, the strain HT371T represents a novel species for which the name Actinopolyspora egyptensis sp. nov. is proposed. The type strain is HT371T (=CGMCC 4.2041T).[...] Read More.

Keywords: Actinopolyspora egyptensis sp. nov., halophilic isolate, polyphasic taxonomy.

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-lactam antibiotic resistance in Escherichia coli commensal faecal flora of healthy population in Taif, Saudi Arabia

Eman Mohammed Halawani

Abstract: One hundred and twenty faecal sample of commensal Escherichia coli strains were collected from different healthy persons and tested for their susceptibility to 12 -lactam antibiotics by disc diffusion and minimum inhibitory concentration methods. Colonization with strains resistant to ampicillin (Amp), amoxicillin, carbenicillin and peperacillin was detected in 36.7% of the tested isolates. Resistance patterns to 3-6 -lactams was observed in 91.7% of the tested E. coli isolates. Transfer of Amp resistance marker by conjugation was usually associated with Strepomycin (Stm) and sulfonamise (Sul) in 100% of tested isoletes and with chloramphenicol (Clm) and tetracycline (Tet) in 63.3 and 45.6% of the isolates, respectively. This suggests that resistance markers to Amp, Stm, Sul, Tet and Clm existed as cossets on cojugative plasmids. Therefore, resistance to these antibiotics could rapidly disseminate and persist in the Saudi Society. All Amp resistant isolates produced one or two types of -lactamases with molecular weights of 28.9 and 28.8 KDa, which indicated TEM-1 and SHV-1. Both types of - lactamases are known to be plasmid-mediated in enteric bacterial species and are common in E. coli commensal faecal flora. Extended-spectrum -lactamases (ESBLs) were not detected in any of the tested strains and therefore, these types of -lactamases are uncommon in commensal E. coli in citizens of Taif. Measures should be taken to prevent the misuse of -lactams and the spread of antibiotic resistance in Saudi Society.[...] Read More.

Keywords: Antibiotic resistance, -lactams, -lactamases, commensal Escherichia coli.

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Molecular characterization of antigens extracted from hydatid cysts of human and other intermediate hosts

Mohammed M. A. Al-Fayadh, Maani N. Al-Shemari and Ihsan E. Al-Saimary*

Abstract: This research includes a study of hydatid cysts Echinococcus granulosus (larval stage on the molecular level, where 7 samples of hydatid cysts were collected from parasite intermediate hosts " Human (liver, spleen, lung) and liver of sheep, goat, cattle and buffaloes”. DNA was extracted from germinal layer cells of hydatid cysts which were isolated shortly or preserved for various periods in 70% ethanol. Genetic analysis of isolated DNA from hydatid cysts collected from human and animals was done by polymerase chain reaction (PCR) to determine genetic variation depending on random amplified polymorphic DNA. In the present study 10 primers have been used, during which the genetic variations were revealed among isolated (extracted DNA) of hydatid cysts which was collected from human and other intermediate hosts except Cows and Buffaloes. The current results of this study have shown the following: 1 - It was found one primer (OPA – 01) was able to diagnose sample numbered 1 which represent the isolated DNA of liver hydatid cyst which was obtained from human at age group 10– 20 years old. 2 - The ability of primer OPC – 10 to determine fingerprinting of DNA sample of Sheep liver hydatid cyst. 3 - The ability of primer OPC – 05 to determine fingerprinting of DNA sample of human spleen hydatid cyst which was obtained from human at age group 30 – 40 years old. 4 - The ability of primer OPE – 07 to determine fingerprinting of DNA sample of goat liver hydatid cyst. 5 – Amplification process to the DNA samples which extracted from cows and buffaloes liver hydatid cysts was not completed by using all 10 primers.[...] Read More.

Keywords: Echinococcus granulosus, molecular, antigens, human.

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Identification of clusters in tissue samples in gene expression data with Principal Component Analysis based on relative variance matrix

Uzma Nawaz* and Asghar Ali

Abstract: Principal Component Analysis (PCA) has been in use as a preprocessing step to clustering for long. We have focused on the clustering of tissue samples in gene expression data. Different clustering techniques and algorithm are available in literature on gene expression data but with the existing ambiguity on the number of clusters, apart from relying on biologically known groups. A consensus is needed to reach on the number of clusters in the wide variety of existing clustering techniques based on different similarity or dissimilarity metrics. The conventional usage of PCA for clustering is either by forcing the unit variance to each variable or the high magnitude of variance of an individual variable is allowed to dominate the entire results of PCA. We propose the use of relative variance covariance method in PCA, so as to give due consideration to the joint and individual variances in the dataset and identify clusters with principal component loadings. We emphasize empirically that the proposed approach of PCA is conclusively more informative than the available approaches to identify cluster structure in tissue samples (sample expression profiles). Clusters formed are valid with the existing results on the data set under study and with valid biological background.[...] Read More.

Keywords: Clustering methods, gene expression analysis, principal component analysis, the relative variance covariance matrix, principal component loadings.

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