نشریه یافته های نوین در علوم زیستی
سال هفتم شماره 1 (پیاپی 23، بهار 1399)

The cave barb habitat is located in a Karst formation along the Sezar River. The springs on the walls of the Sezar River valley may provide a means for fish in surface waters to penetrate into the underground waters. These observations propose the probability for a migratory relationship between Garra gymnothorax in the Sezar River and the cave barbs (Garra typhlops and Garra lorestanensis). In addition, a variety of different body shapes including fusiform and slender body forms are observed among the cave fish. This phenotypical variation may be a sign of an unknown genetic diversity or could be attributed to the variable environmental conditions in different parts of the subterranean habitat. To clarify the situation, we used the sequences of mtDNA cytochrome oxidase subunit I and next generation sequencing method. The results showed that the fusiform and slender body shapes of G. typhlops and G. lorestanensis were not different with regard to their mtDNA and genomic compositions. Moreover, the analysis of the genomic their mtDNA and genomic compositions. Moreover, the analysis of the genomic showed that a limited level of gene flow (less than 3%) from G. gymnothorax probably existed in G. thyphlops. The low level of gene flow may be related to the lower fitness and adaptability of the surface dwelling fish to the subterranean life conditions.

In traditional medicine, extracts of polysaccharide-containing plants are widely employed for the treatment of cutaneus wounds. The brittle star, as one of marine organisms, encompasses bioactive compounds, which confer the healing potency of damaged arms. The aim of the present study is to investigate the effects of extracted polysaccharide from the Persian Gulf brittle star )Ophiocoma erinaceus( on male Wistar rat skin wound healing. In this experimental study, 60 male Wistar rats were divided randomly into 5 groups including control, positive control (treatment with honey), experimental 1 to 3 (treatment with 12.5, 25, 37.5 mg/kg body weight of extracted polysaccharide, respectively). In all groups, the wound was inflicted in the posterior part of the body of rats. Then, rats were treated locally. On the 3th, 7th, 10th and 14th days, samples were collected from the healing hole and histological changes were investigated by light microscopy. Then, quantitative data were analyzed by SPSS software, one-way ANOVA at the level of p<0.05. Microscopic results showed that, in treated wounds by 37.5 mg/kg of extracted polysaccharide, as well as positive control, the re-epithelialization, the angiogenesis and the attenuation of inflammatory cells were significantly improved in comparison with the control group. Maximum epithelium thickness (on the 7th day) and minimum inflammatory cells (on the 14th day) were observed in the experimental group 3 (treated with 37.5 mg/kg of extracted polysaccharide) and positive control, as compared with the control group (p≤0.05). The findings of this research indicated that the polysaccharide extracted from O. erinaceus accelerated the cutaneus wound healing in male rats, which can be used as a natural component in the development of natural source agents for the treatment of cutaneous wounds.

Noise pollution is one of the hazardous factors in the environment. One of the major sources of noise pollution is urban transportation, mostly the subway system and transportation in business centers. In this study, the effects of noise pollution on blood serum proteins level of Wistar male rats were investigated. Rats were divided into 3 groups (1 control and 2 experimental, n=6). The control group was kept in standard conditions and the experimental groups were kept in Tehran Grand Bazaar and the vicinity of Sadeghiyeh metro-station (West Rose Street). After eight weeks, the blood serum proteins of each group were analyzed by electrophoresis assay. Then, the blood serum samples were investigated by Ultraviolet-Visible spectroscopy and chemometrics method (MCR-ALS). Assessment of serum proteins indicated that among 5 essential proteins in the blood, the percentage of alpha-globulins and beta-globulins displayed significant difference (p<0.05) in experimental groups. The UV-Visible spectra and chemometrics method showed that there were different species in both experimental groups as compared with the control group. Thus, the noise pollution of the areas studied led to alterations in blood proteins. Consequently, it seems crucial to take control and prevention measures for noise reduction in these areas.

Phenazine 1-corboxylic acid (PCA) is an antibiotic, which inhibits the growth of a vast number of micro-organisms. PCA has has been applied in fields such as pharmaceutical, agricultural, marine and chemical industries. In this study, the antibiotic properties of PCA (produced by pseudomonas aeruginosa MUT.3, which is kept at the Microbial Collection of Malek Ashtar University of Technology) was studied. The impacts of temperature and light conditions on the activity of PCA was investigated within a 230-day period. To investigate the rate of PCA destruction in the experiment, high performance liquid chromatography (HPLC) was utilized. Moreover, the antibacterial activity of PCA under various conditions was studied by minimum inhibitory (MIC) and minimum biocidal concentration (MBC) methods against E. coli DH5α. The results showed that PCA could be active up to 210 days in darkness (at 25oC). Meanwhile, the antibacterial activity of PCA was reduced to 100 and 50 days by increasing the temperature to 35 and 45oC, respectively. In addition, PCA could be active up to 120 and 10 days in visible and ultraviolet light condition, respectively. The MIC and MBC data were consistent with the HPLC results. Detailed data on the activity and stability of phenazine 1-corboxylic acid under various environmental conditions, as presented in this study, could be helpful in industries and healthcare services.

Urease-producing bacteria can precipitate calcite nano-crystals by producing urease in the presence of urea and calcium. Calcite precipitation resulting from microbial activity is a process which causes cementation of soil particles in nature. The purpose of this study was to isolate urease-producing halophilic bacteria in order to precipitate calcite in saline soil. Natural samples, including soil and saline waters, were selected for this purpose. At First, halophilic bacteria were isolated by salt-containing TSB medium. Then, a selective medium containing phenol red and urea facilitated the isolation of urease-producing bacteria. Hydrolysis of urea by urease causes alkalization of the medium and the formation of pink halo around colonies. Finally, the best isolate was selected for further study by measuring the release of ammonium by the Nessler method. The ability or inability of isolates to produce calcite was investigated by culturing the isolates on sedimentary medium with different salt concentrations for 10 days. In total, 110 halophilic isolates were isolated, among which 58 isolates had the ability of urease production. The microscopic studies of colonies showed that only 6 isolates were able to produce crystals on precipitation medium. Isolate 6 was selected for further study and then analyzed by X-ray diffraction crystals on precipitation medium. Isolate 6 was selected for further study and then analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM) equipped with an energy dispersive X-ray (EDX) detector. Studies of urease activity showed that this strain released 20.86 mM ammonium after 18 hours. This bacterium was identified by biochemical and molecular analyses and the comparison of its 16S rRNA gene sequence showed 99.92% similarity with the similar gene sequence in Staphylococcus xylosus and then this sequence was submitted in NCBI database with the accession number MG655155. This isolate was able to produce calcite in free salt medium, with salinity up to 10%. Nowadays, many efforts have been made to produce environmental-friendly cements, and therefore, the use of urease-producing halophilic bacteria is an appropriate candidate for bio-cementing in saline environments.

The occurrence of extended-spectrum beta-lactamases-producing bacteria is an important public health issue. The aim of this study was to investigate phenotypic and genotypic characteristics regarding the presence of extended spectrum β-lactamase ctx-m, per and ver producing Escherichia coli isolated from raw dairy samples. For this purpose, E. coli were isolated from 247 raw dairy samples (milk and cheese) in Yasooj in 2015-2017, and the isolates were screened for antibiotic resistance, extended spectrum β-lactamase and the presence of ctx-m, per and ver. In total, 200 isolates were selected. The highest frequency of resistance in isolates was against tetracycline (96.5%) and ampicillin (95.5%) antibiotics and the lowest against imipenem (12.5%), In addition, multidrug resistance against four or more antibiotics was observed in some isolates. Extended spectrum β-lactamase resistance was detected in 86 isolates (43%) and ctx-m, per and ver genes were detected in 82, 0 and 7 E. coli isolates, respectively. These findings demonstrated that raw dairy products may be reservoirs for the dissemination of β-lactam antibiotics and that resistance genes could be transmitted to humans through the food chain.

Exopolymers (EPS) are high-molecular-weight polymers secreted by some micro-organisms and have several applications in food, pharmaceutical, packaging and agricultural industries, as well as medicine. Actinobacteria are valuable bacteria in biotechnology and many commercial drugs such as antibiotics, antioxidants and immune-suppressant agents are derived from Actinobacteria. Recently, their other capabilities such as exopolymer production have been taken into consideration. Due to the high potential of actinobacteria in producing various compounds and increased prevalence of infections by antibiotic-resistant pathogens, the aim of the present study was to evaluate the potential of isolated Actinobacteria from various locations of Iran to produce EPS with antimicrobial activity. Appropriate dilutions of the samples were, therefore, cultured in ISP2 medium after treatment. The isolates were primarily identified by morphological tests. Then, their ability to produce EPS was investigated in BHI medium with 5% sucrose. The exopolymers of the most efficient strain were analyzed by UV-visible spectroscopy and FT-IR. Finally, the most efficient isolate was molecularly identified. Of the 120 isolates, 38 were able to produce EPS, and six had significant capability of producing EPS (10-14 g/L) and showed antibiotic activity against Staphylococcus aureus, Bacillus subtilis and Aspergillus niger. The EPS of the strain So49 had high absorbance in 190-230 nm, but did not have absorbance in 260-280 nm. Therefore, it does not have any protein impurity. The EPS has hydroxyl and carboxyl functional groups, according to FT-IR analysis. 16S rRNA gene analysis showed that the most efficient isolate had 99.68% similarity to Promicromonospora xylanilytica.

Charcoal rot caused by Macrophomina phaseolina is one of the most important soil borne diseases with a broad host range including bean, which annually brings a significant damage to this plant. Biological control of charcoal rot is very important because its chemical control harms the environment, microflora and soil fertility. Chemical control of charcoal rot is also difficult and sometimes ineffective. Fluorescent Pseudomonads are able to increase plant growth and inhibit the development of plant pathogens by producing and secreting antibiotics, enzymes, siderophores, and plant hormones. In this study, infected bean plants by M. phaseolina were collected from infected bean fields of Khorramabad (Lorestan Province, Iran) in the summer of 2015. Virulence of fungal isolates was evaluated in a greenhouse and one isolate with the highest pathogenicity was chosen for further experiments. The biocontrol potential of eight Pseudomonas fluorescens strains, whose biocontrol abilities were proved in previous studies, was examined against M. phaseolina in vitro. The growth inhibition of M. phaseolina was examined by dual culture test and the antifungal activity of bacterial volatile and nonvolatile metabolites. P. fluorescens UTPf125, which showed the highest inhibitory effect on the mycelial growth, was selected for greenhouse tests. UTPf125 strain led to a significant reduction (%50) of disease severity and increased fresh and dry weight significantly. Phenol compounds were evaluated 1, 3, 5, 7 and 9 days after inoculation by pathogen. The results showed that the highest value of total phenol content was obtained on the third and fifth days after inoculation, decreasing on the seventh and ninth days.

One of the main strategies to improve plant tolerance is the expression of stress-induced genes, which play a significant role in the ionic balance of plants. SOS3 is one of the important components of SOS-regulated ionic homeostasis pathway. Therefore, the expression of this gene could be an important step towards producing salt-resistant plants. In this work, we have transformed tomato (Solanum lycopersicum) by Agrobacterium (GV3101 and LBA4404) containing plasmids with SOS3 genes. The maximum regeneration rate was determined in cotyledons of CH genotype. The simultaneous use of cotyledons and hypocotyls in the culture medium had the best outcome. In addition, the best time was found to be one day after inoculation. Also, the best transgenic variety was detected for Agrobacterium GV3101, which can be attributed to the interaction between the genus Agrobacterium and the tomato variety. Transgenic plants were transferred to a culture medium containing sequestrene, which caused the acceleration of the seedling growth in particular. The presence of the SOS3 in the transgenic plants was verified by PCR and RT-PCR methods.

The present study aimed to increase the seed germination and the initial performance of pistachio seeds by investigating the effects of the magnetic field and osmopriming treatments simultaneously. 10 treatment levels of 10, 20 and 30 mT for 5, 15, 25 minutes and 1 control treatment (without exposure to a magnetic field) were performed in three replicates and the best level of magnetic surface was selected. The results showed that seeds subjected to the magnetic field showed an increase in plumule length, radicle length, total length of seedlings, fresh and dry weight of plumule as well as radicle and germination speed compared with the control treatment. However, there was no significant difference in the germination percentage and uniformity of seeds. Magnetized seeds, with the superior selective treatment (10 mT for 15 minutes), were primed with solutions of potassium nitrate, humic acid and salicylic acid at levels of 10, 25 and 40 mM and a control level (the best level of magnetism) in three replicates. The best result was obtained from humic acid (25 mM). With regard to the low cost of the purchase or construction of magnetic devices and their positive effects, their application could be recommended (10 mT for 15 minutes) combined with the humic acid (25 mM)) so that the quality of pistachio seedlings production would be increased.

Fire affects vegetation and changes plant succession. In this paper, the vegetation of Sirachal Research Station, which burned in the summer of 2014, was studied and compared with the unburnt areas, based on biodiversity indices. The research was implemented as a factorial experiment in a completely randomized design. First, on the basis of physiognomy, the area was divided into three parts: shrubland, shrubland-rangeland, and rangeland. Each part was, then, divided into two sections, including a burnt area and an adjacent unburnt area (control area). In each area (burnt and unburnt), three sampling units were randomly assigned using PNP method, and vegetation measurements were subsequently performed. Based on data analysis, a total of 141 taxa were identified, belonging to 28 families and 95 genera, including one species of Gymnosperm, 19 monocotyledons and 121 dicotyledons in two burnt and unburnt areas of Sirachal Station. Based on the statistical analysis, using Past3 and SPSS softwares, there was no significant difference in the number of taxa between the vegetation of the burnt and unburnt areas. Of the indicators analyzed in Past3, the number of individual, the index of Menhinick's richness and the Shannon diversity index were significantly different in the treatments sampled from the burnt and unburnt areas. According to the Duncan test average, the number of individuals in the unburnt area, with a canopy cover below 25%, was greater than that in the burnt area, with the same canopy cover, however, no significant difference was observed between the individuals in the burnt area and unburnt area, with the same canopy cover of more than 25%. Also, the richness of the burnt area with a canopy of less than 5% is significantly higher than that in the unburnt area with the same canopy cover.

Pterocephalus (Caprifoliaceae) consists of 30 species worldwide, mainly distributed in the temperate regions of the northern hemisphere, of which 14 species were reported from Iran, including five endemic ones. In this study, 35 leaf-related traits and 30 peduncle-related traits were investigated by light microscopy of 15 samples from 11 Iranian species of Ptreocephalus. Our results showed that there were two types of midrib, six types of leaf indumentum and five types of peduncle indumentum. Crystalized calcium oxalate was observed in the leaves and peduncles of most species except in P. plumosus and P. brevis. The profiles of the peduncles were hexagonal, circular or elliptical. The vascular cylinder shape varied from circular to sinuate form. P. wendelboi, with a very different morphology as compared with other species, also exhibited different anatomical characters. The hexagonal sections of peduncle in P. ghahremanii and P. kurdicus and two samples of P. szovitsii were found to be very similar. However, the mentioned characters were found to be less informative or charachterisation of other species. In conclusion, the results showed that the anatomical characters of the leaves and peduncles might have some taxonomic importance in the identification of some species of the genus Pterocephalus.

Floristic study is one of the most efficient methods of gaining knowledge about biological capacities, as well as management and conservation of plant genetic resources in ecological systems. Zanjan county town is located in a mountainous region with an area of 6763 km2 and the average altitude of 1663 m.a.s.l. Its favorable vegetation diversity is the result of suitable ecological conditions, diverse habitats and appropriate water resources in the region. The central district of Zanjan county town, with an area of 2600.2 km2, was chosen as a representative to show tree and woody shrub species diversity. In order to identify tree and shrub species, life forms and chorology of plants, samples were collected by the conventional method of floristic studies and were, then, identified using taxonomic references. In total, there were 122 tree and woody shrub species, belonging to 76 genera and 39 families, in the studied area. The richest families included Rosaceae (29 species) and Oleaceae (9 species), which comprised 31.15% of the arboreal and woody shrub species. Mesophanerophytes (37.7%) and microphanerophytes (32.79%) were the dominant life forms in the area studied as determined by the Raunkiaer method. The Irano-Turanian vegetative elements were the most important elements in this area based on Zohary approach. Prunus lycioides was found to be endemic to Iran.