Iranian Journal of Biotechnology
Volume:8 Issue: 1, Winter 2010

Abstract Tempranillo is one of the most widely cultivated grapevine varieties in Spain. After several years of clone selection, some highly recommended old clones have been identified in terms of both their qualitative and production characteristics. This study was designed to discriminate among 28 ancient clones of the cultivar Tempranillo (Vitis vinifera). DNAs from clones were analysed using two different molecular markers; microsatellites (SSR) and retrotransposons. Our results indicate that one variant genotype was expressed as three alleles. Further analysis revealed the presence of a chimera, in which the third allele was present in leaf but not root or wood tissue, indicating a functionally double-layered apical meristem. We also report here that one retrotranposon marker was able to discriminate one grapevine clone (VP1) from the remaining clones.

This study represents phylogenetic analyses of two woody polygonaceous genera Calligonum and Pteropyrum using both nrDNA ITS and trnL-F sequence data. All inferred phylogenies using both parsimony and Bayesian methods show that Calligonum and Pteropyrum are each monopyletic and closely related taxa. They have no affinity with Atraphaxis, instead allied with a clade in which the genus is nested. In contrast to Pteropyrum, infrageneric relationships in Calligonum, due to the paucity of informative nucleotide sites in both DNA regions are not resolved.

AbstractThe study of genetic variation and phylogenetic relationships is essential for the efficient selection of superior plant material and conducting introgression breeding programs. In Iran, despite wide geographical distribution no report is available on genetic diversity and relationships of cool season grass populations. For this reason Amplified Fragment Length Polymorphism (AFLP) was used to study 42 populations from eight species of Festuca arundinacea, F. pratensis, F. rubra, F. ovina, Lolium perenne, L. rigidum, Bromus tomentellus and Agropyron cristatum. The number of amplified products ranged from 11 to 78 per primer combination and a total of 497 markers were scored. Jaccard genetic similarity coefficient between populations ranged from 0.15 to 0.88 showing high levels of inter and intraspecific genetic diversity. The UPGMA dendrogram generated by cluster analysis reflected the phylogenetic relationships among species and clearly demonstrated differences in the degree of similarity between accessions. Results indicated that AFLPs are useful to reveal genetic diversity at different taxonomic levels of grasses and may facilitate the selective introgression of useful genes in plant breeding programs

Abstract The genetic traceability of single-cultivar virgin olive oil was carried out by identifying the varieties from which they were produced. The study was based on the analysis of DNA sequences, using a panel of SSRs that could provide genotype-specific allelic profiles. A reliable DNA extraction method for extra virgin olive oil has been defined, and the possibility of using this DNA for fingerprinting the original cultivar has been demonstrated. The DNA was able to amplify SSR fragments and the profile of DNA from the monovarietal oil corresponds to the profile of the DNA from the leaves of the same cultivar. The genetic background of the olive oils that is the olive varieties that have contributed to the blend is successfully recognized, as well.

Probiotics are live cultures of microbes – often lactic acid bacteria but also some other species – fed to animals in order to improve health and growth by altering intestinal microbial balance. Here, we isolated and identified some lactic acid bacteria (LAB) with probiotic properties, from healthy chicken gastrointestinal (GI) tract. Systematic procedures were used to evaluate the probiotic properties of isolated lactic acid bacteria from the microflora of different parts of the GI tract. LAB were examined for the major properties included resistance to 2% bile salt and acidic pH, capability to adhere to the intestinal epithelium and their inhibiting effects on some pathogenic bacteria including Salmonella enteritidis (S. enteritidis) and Escherichia coli (E. coli) growth. Fermentation profile analysis and the sequencing results of conserved 16S rRNA genes showed that 4 clones isolated from duodenum and caeca were Lactobacillus salivarius and the other one clone, also isolated from the duodenum, showed out to be Lactobacillus crispatus. All of the selected LAB were able to adhere to the epithelial cells from chicken. Our results revealed the lactobacilli isolated from different parts of the intestine have the probiotic properties required for use in animal feed. Because the inhibitory effect of these isolated lactic acid bacteria on growth of pathogenic microflora, we suggest that these probiotic bacteria can represent good candidates for therapy against infectious gastrointestinal diseases in chickens.

The influence of whey permeate powder and yeast extract concentration as nitrogen source in skim milk based media on growth, β-galactosidase activity and organic acid profile of Bifidobacterium animalis subsp. lactis Bb 12 in batch fermentation was investigated. B. animalis had diauxic growth in these mediums. β- galactosidase activity increased in growth phase and primary stage of stationary phase and then decreased. Increasing in yeast extract concentration increased specific sugar consumption rate and this rising change, was accompanied with reduction in acetic and formic acid formation. These changes were followed by a decrease in molar ratio of acetic acid to lactic acid consequently. When insufficient initial usable nitrogen and adequate carbon source existed in medium, a disorder between growth and organic acid production was observed. In this case specific enzyme synthesis rate is very high in the early hours of fermentation. Succinic acid was produced continuously at growth and stationary phase in all fermentation media. Citric acid could be consumed at stationary phase by this microorganism and its consumption, was extremely correlated with production of succinic acid at this stage (R2= 0.9). Insufficient nitrogen amounts in medium cased shift from anabolism to catabolism for this microorganism. This phenomenon can affect on organoleptic properties of fermented food.

Many researchers have focused their attention on finding new sources of lipase because of the widespread use of this enzyme in the industry. Soil is a rich source for lipase and therefore the present study was undertaken to screen the Iranian soil for the Bacillus subtilis lipase gene. The soil was collected from different areas of Isfahan, Iran and bacterial colonies were obtained from these samples. These colonies were examined by their physical appearance, biochemical tests and PCR amplification of a portion of their genomic DNA. The obtained results indicate that although from their physical appearance, many colonies were initially selected as being Bacillus subtilis, only four were identified so using biochemical tests. PCR amplification of the genome of these colonies indicated that lipase A was present in all four samples. However the intensity of the bands were different correlating to the differences obtained from the biochemical tests. Upon further investigation it became evident that PCR conditions were not optimum suggesting that altering these conditions can be used as a tool for detecting the differences between these genes. Also the SSCP experiments demonstrated a polymorphism of this gene among these samples. In conclusion, we have characterized an easy and reliable method for the detection of lipase gene from Bacillus subtilis strains. With this method some strains from the Iranian soil were detected and by further screening of the soil, industrially more favorable lipases can be identified.

Egg-laying hens were immunized with Echis carinatus venom and the antibodies were extracted from egg yolk by four different purification methods. The chicken egg yolk antibodies were purified by water dilution method, Polyethylene glycol and ammonium sulphate precipitation method, chloroform extraction method and Lithium sulphate precipitation method. These methods were compared in terms of total protein content, immunospecific anti Echis carinatus IgY activity, in vitro and invivo neutralizing capacity of IgY against Echis carinatus venom. Total immunoglobulin Y (IgY) concentrations varied from 1.6 to 7.0 mg per ml of egg yolk. In Neutralization studies IgY Purified by PEG and Ammonium sulphate precipitation (PEG-AS) showed better results when compared to other purification methods. About 1.25 mg of IgY (PEG-AS) able to neutralize 2LD50 Echis carinatus venom. The results indicate that the purification of IgY by PEG and Ammonium sulphate results in very pure IgY in high quantities (93% +/- 5% of total egg yolk protein) and also capable of neutralizing toxic and lethal components of Echis carinatus venom.

In this study، silver nanoparticles have been synthesized using Aspergillus fumigatus fungus. The effect of three independent variables including glucose content in culture media، initial pH and initial spore concentration on biosynthesis of silver nanoparticles has been investigated. These variables affect the cell morphology، cell mass، size and morphology of silver nanoparticles and reduction degree of silver ions. The formation of silver nanoparticles was confirmed spectrophotometerically. Size and morphology of silver nanoparticles were investigated using transmission electron microscopy (TEM). The effect of culture conditions on cell mass concentration as well as the effect of culture condition on the amount and size of synthesized silver nanoparticles was studied. As a result، the optimum culture condition for biosynthesis of silver nanoparticles was glucose concentration of 16 g/L، pH of 4. 5 and spore concentration of 1. 5×107 spore/L. TEM micrographs showed that the size of synthesized nanoparticles in optimized sample was in the range of 7- 19 nm.