نشریه زیست شناسی کاربردی
سال بیست و نهم شماره 2 (پاییز و زمستان 1395)

Measurements and delineation of organism’s morphologic characterization is an useful tool for identification and taxonomy of them and also, from the perspective of evolutionary ecology, for describing the adaptation of different populations of a species to local conditions is important. Brown Bear is the largest carnivore of Iran and is widely distributed in mountainous areas of North and West of the country. In this study, a total of 21 skulls (including 11 of the Alborz Mountains and 10 skulls of the Zagros Mountains) were collected and 26 variables for each of the skulls were measured. We log-transformed the measured variables to provide normality and using geometric mean the effect of size and age was removed. Significant Differences in measured variables was examined using t-test and then we performed principle component analysis (PCA) to extract orthogonal multivariate axes describing size and shape of the specimens. The results of t test revealed that between Alborz and Zagros specimens eight variables had significant difference. We found that based on the size, Alborz specimens were larger than the Zagros samples. Also, PCA performed on the eight significant variables, indicated a noteworthy difference in the size, but no in the shape, of the skull of the respected population of two regions, which was led to comprise two quite distinct groups.

This study was carried out during 2011 and 2012 on randomized complete bloke design (RCBD) in triplicate with the aim to assess the effect of pollen of A230, Shahrood12 and Tuono on seed germination rate and some of the changes the inner material of seed of A-200 cultivar (mother parent) such as the amino acid, protein, soluble sugar and fatty acids in Steps of before and after germination. The overall results of this study showed that the effect of pollen of A230, Shahrood12 and Tuono on inner material of seeds of A-200 cultivar was significant. The maximum amount of soluble sugars in seed of A-200 from the hybridizing of A230 before germination (29.77%) was observed while the minimum amount of soluble sugars in seed of A-200 from the hybridizing of Shahrood 12 after germination (14.94%) was obtained. Also the maximum amount of total protein in the seeds of A-200 from crossing with of A-230 was observed while the minimum amount of total protein in seed of A-200 from the hybridizing of touno after germination was obtained. Check the resulting of fatty acids levels in seed of A-200 from the hybridizing of A-230, Shahrood 12 and Touno, showed that showed that the effect of pollinizers on fatty acids of seeds of A-200 cultivar was significant. So that, the most and lowest of the fatty acids (methyl oliat) with 74.74% and 71.79% correspond to Touno and A-230respectively. As well as, in this study, it was found that the effect of pollen on the amount of amino acids in seed of A200 from the hybridizing of A-230, Shahrood 12 and Touno, the before and after germination was significant difference. So that, the most and lowest of the Aspartic acid with 0.570% (before germination) and 0.136% (after germination) was correspond to Shahrood 12 and Shahrood 12 respectively.

In order to assess the impact of silicon nanoparticles in improving the growth and physiology characteristics of mahaleb cherry (Prunus mahaleb L.) seedlings a completely randomized experimental design was carried with 4 treatments and 3 replications (each replicate with 9 seedlings). Irrigation treatments included concentrations of 10, 50 and 100 mgr/L of silicon nanoparticles and control with tap water which was irrigated every three days based on field capacity. At all concentrations of silicon nanoparticls with increasing silicon nanoparticles concentration the rates of photosynthesis, stomatal conductance and transpiration increased. With increasing silicon nanoparticle concentration water potential of mahaleb seedlings was decreased (more negative), but the relative water content of leaves did not differ among treatments. Although, with increasing silicon nanoparticles, collar diameter and height growth did not differ, however, other growth parameters were increased. In general, it can be stated that in this study the use of silicon nanoparticles, especially at concentrations of 50 and 100 mgr/L growth and physiological activities of mahaleb seedlings were improved.

This study was done using rice bran for absorption of Zinc from returned-water of semi-intensive Trout culture systems in concrete ponds, Mazandaran province, Iran. The sampling period was 4 months and well's water used for ponds; 90% of returned-water was reused as input water, after purification and absorption of suspended solids using "Media system" and sedimentation's pool. Zinc metal was detected and evaluated from output water of six octagonal ponds using Photometer (Palintest-7000) and flame atomic absorption method (Thermo-MS). Rice bran was used as a natural Zinc adsorbent in 4 concentrations (0 as control, 10, 15 & 20 gr/l) and 5 treatment times (5, 15, 30, 90 & 120 min). The results showed that there are no difference between amount of Zn in well, input and output waters with 0.11±0.01, 0.13±0.02 and 0.12±0.01 mg/lit, respectively (P>0.05). There was any absorptions at the times of 5 & 15 minutes (P>0.05). The results also showed that the optimum absorption of Zn was occurred with 0.28±0.05 mg/lit (70.0%) at 90 min and 15 g/l and the minimum absorption was obtained with 0.07±0.02 mg/lit (17.5%) at 30 min and 20 g/l of concentration (P

Hemolysin is an extracellular protein released by many pathogenic and nonpathogenic bacteria. It belongs to cholesterol-dependent cytolysins (CDCs) which are a large family of pore-forming toxins. Their mechanism of action is cholesterol identification as a receptor. In this study, a type of hemolysin produced by Bacillus pumilus SAFR0032 was investigated. Firstly, molecular dynamic simulations of Hemolysin in biological membranes were performed using Gromax software to evaluate the stability of proteins in biological membranes. Amino acids which involved in toxin-membrane interactions were also identified by Autodock software. Subsequently, crucial mutations were created in the key amino acids of interaction and function of mutant proteins were checked by Pop Music server. Our findings demonstrated that critical hemolysin mutations could reduce hemolysin tendency to cholesterol and weaken their interaction. All in all suggesting that three-dimensional structure of hemolysin can be considered as a novel concept in pharmaceutical field to improve current drugs which used to cure hemolysin-associated diseases.

Beta Nerve growth factor (β-NGF) was first known for its vital role in development and survival of neurons. This protein, which belongs to the neurotrophin family, plays a considerable role in the treatment of neurodegenerative diseases such as Alzheimer’s disease (AD). As a result of its characteristic, recombinant human β-NGF (rhβNGF) was expressed in two different strains of E.coli for the first time in Iran. β-NGF has three disulfide bonds in its native and functional structure, so the cytoplasmic reducing environment of E.coli is not appropriate for its expression. Therefore, the oxidative space of periplasm for production of correctly folded β-NGF was considered. In this study, hβNGF cDNA obtained from NCBI data bank after codon optimization and subcloning in pET39b() vector containing DsbA gene was transformed (using heat shock) to BL21(DE3)pLysS and BL21(DE3) strains of E.coli. Co-expression occurred via induction of promoter with 1 mM of IPTG. Consequently, extracted proteins from these two strains were compared with each other with SDS-PAGE and Dot blot techniques. The data shows βNGF expression especially in BL21(DE3) strain of E.coli.

In order to biomass production and removal of nitrogen and phosphate from municipal wastewater, Chlorella vulgaris was cultivated. Amount of biomass, concentration of nitrate, ammonium, and phosphate was measured. The maximum amount of biomass was 2 g dw/L. The regression between biomass production and removal of nitrogen (p

Pseudomonas putida is one of the most well-known bacteria and many strains of this bacterium have been reported from all over the world. Some strains are considered as the most important phosphate solubilizing agents in the soil, maximizing plant access to this element and as a result improve the plants growth. Several factors influence the natural growth of the bacteria in soil of which, the most important factors are pesticides. In the present study, effects of two widely used agricultural pesticides, Diazinon and Benomyl in different doses (250, 500, 1000, 2500 and 5000 mg/L) and at different temperatures (25, 30, 35, 40 and 450C) were studied on a selected isolate of P. putida. The results showed that both pesticides even at the lowest dose (250 mg/L) significantly reduced bacterial growth but not completely. The bacterial population growth was very slow in the range of recommended dose (1000 mg/L) for both pesticides. Benomyl did not stop bacterial growth completely at any of the selected doses, whereas Diazinon at concentrations of 2500 and 5000 mg/L became lethal for bacterial cells. At temperatures above 300C a significant decrease was observed in normal bacterial growth which was higher in the presence of both pesticides.

Bioleaching is the biological conversion of an insoluble metal compound to form soluble in water which was influenced by several parameters. One of the important microorganisms involved in the uranium bioleaching process, is Acidithiobacillus ferrooxidans. Based on the importance and the effects of environmental parameters in the uranium bioleaching process and bacterial activity, the aim of this study is to obtain the optimal values of 5 important parameters in the process of uranium bioleaching. For this purpose, the natives Acidithiobacillus ferrooxidans, APH medium and the ore from Anomali 2 of Saghand in Yazd used and different parameters affecting on the uranium extraction, including shaking, pH, temperature, pulp density, and initial ferrous iron concentration were studied at different levels. The results of this study indicated that the maximum yields of uranium extraction and Eh values were observed at 150rpm, pH= 2, temperature 35 ° C, PD=5% (w/v) and 10 g/L of [FeSO4.7H2O].

The genus Amaranthus (Amaranthaceae) includes about 60-75 species. Taxonomy of this genus is difficult due to high hybridization, domestication of some species, high morphological diversity, gene flow, and many intermediate forms that have been reported. The main purpose of this study was analyzing leaf anatomical characters for nine species of the genus and also evaluating the systematical efficiency of these characters. In this study the anatomical structure of the midrib, lamina and petiole was studied by light microscopy. These characters confirm the classification of species in the subgenus, section and subsection. In general it seems that the whole anatomical characters of the studied species can be effective in association with morphological characters.

In present study, oleaginous yeast Rhodotorula mucilaginosa strain UIMC35 was isolated and identified for SCO (single Cell Oil) production. Flow cytometric technique was employed for the monitoring of fluorescence intensity of the cells (channel FL2), cell size (by FSC parameter) and the cell granularity (by SSC parameter). The relationship between fluorescence intensity and lipid content in order to quick and easy calculation of the amount of lipid content was presented. Changes in various factors such as lipid and biomass production, lipid content, lipid and biomass production efficiency, the amount of sugar, the amount of nitrogen, C/N ratio and pH were investigated at different stages of yeast strain batch culture. The highest rates of lipid production, lipid content and lipid production efficiency by this yeast strain were achieved 6.57 g/l, 67.04 % and 21.13 %, respectively. Decreasing of C/N ratio in the later stages of yeast growth caused the reduction of the lipid production rate.

The purpose in this research to investigate two species Pteris by anatomy method and evaluation of similarities and differences between them in the forests of northern Iran. Therefore, the populations of two species of the Pteris cretica and Pteris dentate were collected from forests of Mazandaran, Guilan and Golestan. The results of the findings show that these two species of ferns , based on the anatomy of the main components I, II and IV are different from each other , but based on other main components aren’t significantly different from each other. Also, the dentate species populations based on principal component except the sixth, no significant differences were observed, and that could indicate the presence of more than one sub- species of the dentate in northern Iran.The results show that two species of ferns, in terms of anatomy based on principal component first, second and fourth different together, but the other main components do not differ significantly. Also among the populations of Dntata based on principal component except the sixth, there was a significant difference that could indicate the presence of more than one subspecies of Dntata northern Iran.

Salt stress due to chlorine is one of the limiting factors in plant growth. An increasing of antioxidative enzymes activity is a defensive response of salt stresses. In this research, the effects of four chlorine concentrations in irrigation water (10, 20, 40, 80 mg/l CaCl2) on the activities of enzymes peroxidase, ascorbate peroxidase and polyphenol oxidase and malondialdehyde content, total leaf protein, and peroxidase zymogram in three greenhouse tobacco varieties were investigated. The results showed that an increase in chlorine concentration up to 80 mg/l, peroxidase enzyme activity decreased in Cooker. The highest and lowest ascorbate peroxidase activities of all stressed varieties were seen in 40 and80 mg/l treatments, respectively. polyphenol oxidase activity induced in Kentucky and Virginia by 40 mg/l treatment and reduced under 80 mg/l treatment in all three varieties. The measurement of malondialdehyde content in Cooker showed that there was no significant difference among all treatments, except in 20 mg/l concentration which was increased. Malondialdehyde content decreased significantly in Kentucky in all treatments compared to control. Malondialdehyde content of Virginia also showed no significant difference, except in 20 mg/l concentration which was reduced. Total protein content of Kentucky and Virginia was reduced with increasing of chlorine concentration.

The emergence of drug resistant pathogens indicates the need to discovery of new antibiotics. In the search for a new antibiotic producing microorganism, an Alcaligenes faecalis subsp. faecalis strain was isolatedfrom oil polluted soils near Dezful. One factor at a time was used to find important variables in antimicrobial compound production and upon its result pH = 9, temperature 35 ˚C, NH4Cl 0.34%, sodium acetate 2% and K2HPO4 0.02% have greatest effect on production, respectively. Acetate and NH4Cl concentration, shaker revolution and fermentation time were selected for optimization by response surface method with central composite design. The best result achieved by sodium acetate 1.88%, NH4Cl 0.29%, shaker 3 rpm and fermentation time 6.7 day which had 47% higher production than one factor at a time method. Results also indicated strong interaction between some variables.