فهرست مطالب

  • No. 2801, 2003
  • تاریخ انتشار: 1381/11/15
  • تعداد عناوین: 19
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  • H. Zeinali, A. Arzani, K. Razmjo Pages 1-9
    There is little information available on morphological and agronomic traits, as well as chemical compositions of Iranian mint landraces. This study was conducted to investigate the morphological, agronomic and oil content characteristics of Iranian mint landraces using twelve landraces, three of which belong to Mentha longifolia, and the remaining, Mentha spicata L, originated from central regions of Iran. Days to 50% and 100% flowering, plant height, number of lateral branches, leaf length, leaf width, herbage yield per plant, number of nodes per main stem, number of nodes per lateral branch, spike length of main stem, number of spikes per plant, height of lateral branches and spike length of lateral branches were recorded and used in this study. The results showed the significant differences among landraces for all tested traits with the exception of the number of nodes per lateral branch. Two accessions, including Mzin3 with 1.9 ml/100g essential oil content, and Mzin6 with 2.1 ml/100g essential oil content, produced the highest essential oil content. Mzin3, with15.9 g/plant herbage dry yield and Mzin6 8.1 g/plant, produced the highest and lowest herbage yield. Genotypic and phenotypic coefficients of variation were high for the spike length of the main stem (32.3%, 29.7 %), the number of spikes per plant (41.7%, 28.5%), and the essential oil content (38.5%, 34.1%), and was low for days to 50% flowering (11.9%, 10.7 %), days to 100% flowering (9.2%, 6.5%) and number of nodes per main stem (9.7%, 6.9%). Stepwise regression analysis indicated that leaf length justified 53 percent of the total variation and was accounted as the most important component of essential oil content. Cluster analysis divided the landraces into 3 groups, each of which having 5, 3 and 4 clones. The number of nodes per main stem, number of lateral branches, spike width of main stem, leaf width, days to 50% flowering, plant height and nodes per lateral branches were the major sources of diversity among the mint clones. Strong association was observed between leaf length and essential oil content (r = 0.73). Therefore, under tested environmental conditions, leaf length may be used as a morphological criterion for selecting clones with high essential oil content in mint.
    Keywords: Mint, mentha spicata, mentha longifolia, essential oil content, diversity
  • F. Tabandeh, B. Yakhchali, S. A. Shojaosadati, M. Khodabandeh, M. H. Sanat Pages 11-17
    The batch fermentation production of human growth hormone (hGH) was studied in a new recombinant Escherichia coli. The effect of different levels of dissolved oxygen and glucose concentration on cell density and substrate utilization were evaluated. The results indicated that the optimum level of dissolved oxygen was 25% of air saturation. The specific growth rate reached a maximum for an optimal glucose concentration of 5 gl-1, the maximum yield was 0.58 gg-1 and glucose was completely consumed after 10 hrs. The growth of recombinant E. coli on semi-defined and complex media was compared. The results demonstrated that dry cell weight and maximum specific growth rate were 2.35 gl-1 and 0.4 h-1 on a complex medium, respectively, but they were 3.3 gl-1 and 0.24 h-1 on semi-defined medium. The plasmid stability and hGH production during batch fermentation were investigated. The results suggested that the specific growth rate is the most important factor on hGH production and should be investigated in fed batch cultivation to get high cell density.
    Keywords: Batch fermentation, recombinant, escherichia coli, human growth hormone, microbial kinetics
  • M. Aliasgharpour, H. Hekmatshoar, M. Hosseyni, F. Some, Eh Pages 19-31
    The chemical nature of secretion by the stigma and transmitting tissue in Datura stramonium was studied by light microscopy using Sudan black B, Coomasie brilliant blue (CBB), Toluidine blue, Safranin, and PAS. The stigmatic secretion reacted positively for lipids. During development, stigmatic cells became separated and intracellular lipids were transferred to intercellular spaces where they gradually migrated to the stigma surface. Excretion of the lipids was a continuous process and persisted during maturity and even in pollinated and opened flowers (post-pollinated). Lipid secretion was associated with cell autolysis in papillae and in secretory cells of the stigma, particularly in superficially located ones. The transmitting tissue cells also showed glandular activity with the release of a polysaccharide rich substance. The pollen germination and pollen tube growth seem to be closely dependent upon these secretions in Datura stramonium. The different nature of the secretion of the stigma (lipids) versus secretion of the transmitting tissue of the style (carbohydrates), supports the hypothesis that the pollen tube metabolism changes from autotrophic to the heterotrophic upon entering the transmitting tissue from the stigma surface.
    Keywords: Datura stramonium, secretory cells, lipids, carbohydrates, pollination, stigma, transmitting tissue, papillae, compatibility
  • M. Sheidai H. Jahanbakht, P. Sofi, Siyavash Pages 33-42
    Tea (Camellia sinensis) is one of the most economically important crops and is considered to be the national drink of Iran. Although there has been an intensive cytogenetic study of tea in different regions of the world، there has been no report from Iran. Therefore، the present investigation was carried out in order to present the basic cytogenetical features of various tea cultivators grown in the country. The meiotic analysis of the tea cultivators studied showed variation in the prophase sub-stage of meiosis-I، due to the occurrence of a synezetic knot and post pachytene diffuse sub-stage. All tea cultivators studied were diploid، with the chromosome number n=15. Although the major feature of chromosome association was bivalent formation، quadrivalents were formed in the cultivator 3013، possibly due to structural hybridity. The ANOVA test showed the presence of a significant difference among the cultivators for terminal، intercalary and total chiasmata، as well as ring bivalents indicating their genomic differences. Cluster analysis and PCA ordination of cultivators which are based on meiotic characteristics، group those cultivators which show cytogenetic similarities.
    Keywords: Tea, cytogenetic, chiasma frequency, cluster analysis
  • A. Moradshahi, B. Salehi Eskandari, B. Kholdebarin Pages 43-50
    Drought is considered as one of the most important limiting factors for oil seed canola plant (Brassica napus L.) growth and productivity in Iran. On the basis of root and shoot dry weight as affected by water stress exerted by PEG 6000، out of 9 canola cultivars، a relatively tolerant (cv. Aghaii) and a sensitive cultivar (cv. PO4) were selected. Their responses to low water potential with respect to changes in activity of the antioxidant enzyme ascorbate peroxidase، K+ uptake، and its translocation to the shoots and production of osmoprotectants proline and soluble sugars were analyzed and compared. Although low water potential did not influence ascorbate peroxidase activity، constitutively the enzyme activity was significantly higher in the tolerant cultivar. A significant increase in root proline content was observed with a decrease in external water potential up to -. 48 MPa. The increase was 2 to 3 times higher in the tolerant Aghaii cultivar. Although the total soluble sugars tended to increase under low water potential، the amounts accumulated were mostly comparable in both cultivars. K+ uptake by the roots and its translocation to the shoots decreased at low water potential، however the amount taken up and translocated was consistently higher in the tolerant cultivar. Constitutively higher ascorbate peroxidase activity along with the higher rates of proline accumulation and K+ uptake are taken as part of the mechanisms which confer drought tolerance to the Aghaii cultivar.
    Keywords: Water stress, canola plants, ascorbate peroxidase, proline, soluble sugars, K+ uptake
  • B. Shiran, A. M. Mashayekh Pages 51-55
    A restriction-site analysis of chloroplast DNA (cpDNA) was carried out to evaluate the level of diversity in Vicia faba L. germplasm selected from different geographical regions using 11 restriction endonucleases. We analyzed 214 restriction sites in 18 accessions of Vicia faba. All of the accessions had identical cpDNAs, pointing out the ancestral character of all the accessions are of only one gene pool, and all of them must have evolved through the same maternal lineage. Molecular size of the chloroplast DNAs obtained was 123.25 kb, indicating that it had lost one of the inverted repeats. Due to lack of cpDNA diversity, it is concluded that the broad bean has passed through a genetic bottleneck during domestication and lost most of its cytoplasmic variability. The present study favors the monophyletic origin of its cytoplasm, and accordingly, of Vicia faba.
    Keywords: Chloroplast DNA, restriction site analysis, vicia faba L. germplasm
  • S. Vallian, K. S. Chang Pages 57-64
    Our previous studies showed that the promyelocytic leukemia protein, PML, functions as a cellular and growth suppressor. Transient expression of PML was also found to repress the activity of the epidermal growth factor receptor (EGFR) gene promoter. In this study, we have examined the effects of PML on A431 cells, which express a high level of EGFR protein. The PML gene was introduced into the cells using the adenovirus-mediated gene transfer system. Western blot analysis on the extracts from the cells expressing PML showed a significant repression in the expression of the EGFR protein. The cells were examined for growth and DNA synthesis. The data showed a marked reduction in both growth and DNA synthesis rate in the cells expressing PML compared with the control cells. Furthermore, in comparison with the controls, the cells expressing PML were found to be more in G1 phase, fewer in S and about the same number in the G2/M phase. These data clearly demonstrated that the repression of EGFR expression in A431 cells by PML was associated with inhibition of cell growth and alteration of the cell cycle distribution, suggesting a novel mechanism for the known growth inhibitory effects of PML.
    Keywords: PML, EGFR, cell cycle, A431 cells, expression
  • M. Moazzen Pages 65-78
    Chloritoid is crystallised with chlorite، white mica and garnet in chlorite zone metapelites of the regional metamorphic rocks of the Sanandaj-Sirjan metamorphic belt in southern Iran. Chemistry of coexisting minerals is studied using microprobe analysis. Application of the chlorite-chloritoid geothermometry gives temperatures of 515°C and 557°C. The Chlorite-garnet Fe-Mg exchange geothermometer indicates temperatures between 442°C and 460°C for various pressures. A comparison of the results from two geothermometers، along with a study of mineral assemblages in the rocks show that the chlorite-chloritoid thermometer overestimates the temperature by about 70°C.
    Keywords: Sanandaj, Sirjan metamorphic belt, metapelites, chlorite, chloritoid, garnet geothermometry
  • B. Etemadi, A.Taeb, H.Sharghi, A. Tajarodi, H. Naeimi Pages 79-83
    The crystal structure of the compound C20 H24 N2 O24 was determined by direct methods. The crystals are monoclinic، space group P21/n، and unit cell parameters are: a= 10. 2342 (9)، b=4. 8763 (5)، c=19. 3578 (11) A، =98. 9632 (10)، V=956. 6 (5) A3، Z=2، Dc=1. 239grm-3، Dm=1. 22grm-3. The final R-factors are converged to R=0. 059 and Rw=0. 056 for 553 independent observed reflections. The molecules are linked by van der Waals forces and an intramolecular hydrogen bond is present between O2 and N1 atoms. The ring system displays a deviation from planarity.
    Keywords: Crystal structure, salen, schiff bases, salicyladi, mine
  • M. Shams Lahijani, M. G. Ghorbani Pages 85-96
    The deleterious effects of morphine sulphate addiction on the central nervous system are well documented. Previous studies have shown that the passage of morphine from the placenta barrier can influence the normal development of embryos, such as those of humans, by specific mechanisms. So, for the first time, for the purpose of investigating the effects of morphine sulphate on pregnant animals, three groups (control, sham and experimental) of Sprague-Dawley female rats were chosen and 0.1, 0.2 and 0.3 mg/ml of morphine sulphate were administered orally in drinking water to each female rat (n=5-7) in four experimental groups in weeks 1, 2, 3 and 3 weeks of pregnancy. Caesarean sections were performed at the end of the gestation period; foetuses (n=27-63) and their placentas were examined externally; the number of foetuses and their resorption sites were also recorded. Results showed that 0.1, 0.2 and 0.3 mg/ml of morphine sulphate causes significant increase in the percentage of teratogenicity (except in week 3) (p<0.05). Although 0.1mg/ml of morphine did not have any effect on the diameter and weight of the placenta and the number of foetuses, 0.2 and 0.3 mg/ml of morphine caused a significant decrease (p<0.05) in the weight and diameter of placentas, the number of the embryos, their body weight and crown-rump length of fetuses. The foetal weight of all four groups decreased significantly (p<0.05). These results also showed that teratogenic effects of oral administration of morphine in rats mostly happens in week two (organogenesis) of embryonic development.
    Keywords: morphine, teratogenicity, sprague, dawley rats, embryo
  • M. J. Zamiri, A. Rezaei, Roodbari Pages 97-106
    The relationship between blood physiological attributes and carcass characteristics was studied in 40 randomly selected 8-month-old ram lambs of Ghezel and Mehraban (20 rams per breed) sheep. One day before slaughter, blood samples were obtained after a 24 hr fast. Serum samples were assayed for glucose, cholesterol, serum urea nitrogen (SUN), total protein, albumin, triglycerides, creatinine, and calcium and magnesium ion concentrations. Dry matter, crude protein, crude fat (ether extract) and ash were determined in carcass soft tissues (carcass without bone and tail fat). Overall, serum cholesterol (r=-0.70; P<0.01) and creatinine (r=-0.48; P<0.05) concentrations were negatively correlated with the crude protein percentage of soft tissues dry matter (CPDM) in these sheep. Serum cholesterol concentration was positively correlated with the total dissected fat in both Ghezel (r=0.83; P<0.01) and Mehraban sheep (r=0.60; P<0.01). CPDM was negatively (P<0.01) correlated with a serum glucose concentration in Ghezel (r=-0.60), and with a SUN concentration in Mehraban (r=-0.60). A positive correlation was also found between the serum cholesterol concentration and crude fat (ether extract) as a percentage of the soft tissues dry matter in Ghezel (r=0.66; P<0.01). In general, fewer carcass traits in Mehraban were significantly correlated with cholesterol, and the coefficients were generally smaller than those for the Ghezel breed. The regression equations showed that blood cholesterol, glucose, triglyceride and SUN could be regarded as good predictors of carcass characteristics in Ghezel sheep. Serum cholesterol concentration was the only blood attribute that was retained in equations for Mehraban sheep. The coefficients of determination for Mehraban sheep were much smaller than those for Ghezel. More research with a larger number of animals is needed before they find application in carcass evaluation.
    Keywords: Blood attributes, sheep, carcass characteristics, Mehraban, Ghezel
  • S. Khoei, B. Goliaei, A. Neshasteh, Riz Pages 107-116
    Many cell lines, when cultured under proper conditions, can form three dimensional structures called multicellular spheroids. These spheroids resemble in vivo tumor models in several aspects. Therefore, studying growth characteristics and behavior of spheroids is beneficial in understanding the behavior of tumors under various experimental conditions. In this work, we have studied the growth properties, along with the thermal characteristics of spheroids of DU 145 human prostate carcinoma cell lines and compared the results to monolayer cultures of these cells. For this purpose, the DU 145 cells were cultured either as monolayer or spheroids. At various times after initiation of cultures, the growth properties of spheroids as a function of seeding cell number was determined. To evaluate the thermal characteristics of spheroids, they were heated at various stages of growth at 43 °C for various periods. The thermal response was judged by the survival fraction of colony forming cells in spheroids or monolayer culture following heat treatment. The results showed spheroids were more resistant to heat than monolayer cultures at all stages of development. However, the extent of this thermal resistant was dependent on the age, and consequently, the size of the spheroid. The result suggests that the differential thermal resistance of the spheroid cultures develop gradually during the growth of spheroid cultures of DU 145 cell line.
    Keywords: Hyperthermia, multicellular spheroids, thermal resistance, DU 145 prostate cell line
  • K. Nikookar, A. Moradshahi, M. Kharati Pages 117-125
    Dunaliella salina was isolated from Maharlu salt lake in Shiraz, Iran, and was analyzed for the effects of salinity stress on its growth, pigment content and ascorbate peroxidase activity. Growth, expressed as number of cells ml-1, which was most rapid at 2 M NaCl, was reduced at salinity extremes. During the exponential phase of growth, increasing salinity from 0.5 to 4 M NaCl increased Chl a from 0.3 to 0.9 pg cell-1, while β-carotene was decreased from 3.6 to 2.4 pg cell-1 and Chl b remained unchanged. At stationary phase, increasing salinity increased the pigment content of cells. β-carotene content per cell reached its highest value of 10.1 pg at 4 M NaCl. Maximum β-carotene to total Chl ratio of 7.4 was obtained at 2 M NaCl. The TLC chromatogram of pigments extracted from cells at the exponential phase of growth resembled that of spinach leaves while the chromatogram of pigments extracted from cells at the stationary phase resembled that of carrot and commercial β-carotene. A significant increase in ascorbate peroxidase activity was observed with increasing salinity from 1 to 4 M NaCl. It is suggested that increased capacity to scavenge ROS may help to optimize algal biomass and β-carotene production.
    Keywords: Dunaliella salina, isolation, salinity, β carotene, ascorbate peroxidase
  • Sahebi, M. R. Rahiminejad, A. Ghahreman Pages 127-135
    This study concerns the taxonomic status of Hordeum marinum sensu lato in Iran. Its geographical distribution in Iran has been reported. Based on the morphological study, the taxon contains two subspecies: marinum and gussoneanum (Parl.) Thell. in Iran. Morphological descriptions along with a key separating the two subspecies are provided. Furthermore, morphological variations of the subspecies of Hordeum marium Hudson in various habitats have been studied. In order to facilitate identifications, three photographs and drawings illustrating the herbarium specimens have been provided.
    Keywords: Poaceae, triticeae, hordeum marinum s. l., Iran
  • M. Yousofi, A. Aryavand Pages 137-144
    Flow cytometry (FCM) was used to determine the ploidy levels of six different populations of Agropyron cristatum (L.) Gaertn. (Poaceae) in Iran, using a diploid cultivated barley (Hordeum vulgare L.) as an internal reference. According to flow cytometric data, tetraploid (2n = ± 28) and hexaploid (2n = ± 42) levels were detected among the examined populations and these results were supported by chromosome counting on the same materials included in this study. The mean nuclear DNA content (2C value) of the populations were then estimated, ranging from 26.41 to 27.56 pg for two varieties of Agropyron cristatum subsp. pectinatum, and 43.47 pg for Agropyron cristatum subsp. incanum. The relationships between morphological variations observed among the taxa and ploidy levels were also discussed.
    Keywords: Flow cytometry, ploidy determination, nuclear DNA content, agropyron cristatum
  • P2O5 / SiO2 AS CATALYST FOR THE PREPARATION OF 1، 1-DIACETATES UNDER SOLVENT-FREE CONDITIONS
    H. Eshghi, Z. Gordi, A. Khanlarkhani Pages 145-148
    A facile and efficient method for the preparation of 1، 1-diacetates of aldehydes is improved. P2O5/SiO2 catalyzed 1، 1-diacetates formation from aldehydes in dry media. Advantages of this method are the use of an inexpensive and selective catalyst with high yields in simple operation and short reaction time under solvent-free conditions.
    Keywords: 1, 1, Diacetates, phosphorous pentoxide, protection, aldehydes, silica gel
  • B. Haghighi, M. Akmaly Pages 149-160
    Interaction of glucose 6-phosphate dehydrogenase from S. aureofaciens with NAD+, NADP+ and glucose 6-phosphate were investigated using different fluorescent probes. Binding of NAD+, NADP+ and S-NADPH to the native enzyme quenched intrinsic protein fluorescence by 100%, 10% and 21%, respectively, from which Kd values of NAD+ (6.5 mM), NADP+ (92.0 µM) and S-NADPH (122.0 µM) were calculated. Binding of NAD+, NADP+ and S-NADPH to the pyridoxylated enzyme in which pyridoxal 5`-phosphate occupied a glucose 6-phosphate site, quenched the fluorescence of the pyridoxal group on the enzyme by 20%, 57% and 96%, respectively. Kd values for the pyridoxylated enzyme were also calculated for NAD+ (1.0mM), NADP+ (301.0µM) and S-NADPH (151.0µM). When NAD+ was bound to the native enzyme-S-NADPH complex, to which S-NADPH was bound to only one subunit leaving the other free, the S-NADPH fluorescence was quenched with a 10 nm blue shift in its emission spectrum. NADP+ binding, however, enhanced S-NADPH fluorescence. The fluorescence of S-NADPH bound to the pyridoxylated enzyme was enhanced upon NAD+ binding with a 5 nm blue shift, while NADP+ binding had no effect. A substrate analog, glucose 1-phosphate, inhibited the enzyme competitively with respect to glucose 6-phosphate and uncompetitively with respect to NAD+. Binding of NAD+ to enzyme-glucose 1-phosphate complex quenched protein fluorescence (44%) with decreasing Kd value from 6.5 mM in the absence of glucose 1-phosphate to 2.2 mM in its presence. NADP+, however, showed opposite effects. The data demonstrated that S.aureofaciens glucose 6-phosphate dehydrogenase undergoes different conformational changes upon NAD+ and NADP+ binding, and modification of glucose 6-phosphate binding site by pyridoxal 5`-phosphate pulls the enzyme in a conformation suitable for NAD+ binding.
    Keywords: Glucose 6 phosphate dehydrogenase, streptomyces aureofaciens, pyridoxal phosphate
  • T. Eslamzadeh, B. Nasernejad B. Bonakdar Pour, A. Zamani, M. Esmaail Bygi Pages 161-167
    The removal of copper (II), zinc (II), and chromium (III) from wastewater by carrot residues (CR) was investigated to evaluate cation exchange capacity. The effects of solution pH and co- ions were studied in batch experiments. Adsorption equilibria were initially rapidly established, and then decreased markedly after 10 min. Column experiments were carried out in a glass column filled with CR to evaluate the metal removal capacity. The influences of the feed concentration and feed rate were also studied in order to compare the dynamic capacity for metal binding in different feed concentrations.
    Keywords: Carrot residues, heavy metals, metal binding, removal
  • S. Akbari A. T. Law, M. Shariff Pages 169-175
    The acute toxicity of a Malaysian crude oil to red snapper، Lutjanus argentimaculatus، black tiger shrimp and Penaeus monodon were investigated. The animals were exposed to water soluble fractions (WSF) of crude oil in a flow-through bioassay system and the toxicants were analyzed by gas chromatography (GC) and gas chromatography and mass spectrometer (GC-MS). The 96 h LC50 values of the WSF of crude oil for fish and shrimp were 3. 24 ± 0. 21 and 8. 52 ± 0. 89 ppm of WSF of crude oil، respectively. In this investigation، the fish were more sensitive to crude oil than the shrimp، with respect to the similarity in their habitations.
    Keywords: Crude oil, acute toxicity, fish, shrimp