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It is clear that DNA concentration and biological detection devices have many applications in the fields of genetics and biotechnology. For this goal, some similar devices have been designed working with the laser light which the disadvantages of them are high prices and the use of significant amounts of sample volume. But this designed device which works with LED light has very cheap manufacturing cost. The amounts of DNA used in this device are very low, about a few micro-liters and measurement of small, fast and portable it is also the advantages of these devices. The Data recorded as voltage versus time and the Fourier transform the frequency domain. From the frequency curve, by using the Byrlambrt it is possible to obtain the relative concentrations of DNA, viruses and assays measuring DNA damage and many other applications. By use of this device, the concentration of DNA colored with three different pigments was measured.

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New properties of nano-materials have made nanotechnology the leading part of biology and medical sciences. Due to their various biomedical properties, iron-based magnetic nanoparticles (MNPs) have been highly considered by biological researchers. Nowadays, increasing resistance to antibiotics is a major problem in treating clinical infections. Finding new antibacterial agents is therefore essential for the treatment of resistant strains. In this study, the iron oxide MNPs were produced using culture-medium supernatant of a newly isolated bacterium to investigate the inhibitory effects of the NPs on strains with a major role in clinical infections. Biosynthesis of iron oxide MNPs were detected by UV-Vis spectroscopy and the average size of particles was estimated by dynamic light scattering technique. The anti-bacterial activity of these NPs against E. coli and S. aureus was investigated using methods for the calculation of bacterial sensitivity coefficient. In the presence of NPs, the highest sensitivity coefficient value was observed for E. coli in 1xMIC concentration. On the other hand, S. aureus showed the lowest value. The death rate of the two strains in contact with NPs followed the first order kinetic equation and the survival rate decreased with the increase of exposure time. The results of this study as well as the high functionality of iron oxide MNPs, make its application desirable in the prevention and treatment of clinical infections.

 

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The identification of the characteristics of native halophytic species is very important for their practical application. The present study was carried out to identify the halophytic species of a desert and highly saline region around the city of Khosf, southern Khorasan Province, and to detect their general tolerance mechanisms (i.e. salt exclusion or inclusion). Sodium accumulation in the roots and shoots of seven species, including Launaea arborescens, Peganum harmala, Pteropyrum olivieri, Artemisia santolina, Zygophyllum eurypterum Boiss, Aerva javanica, Pulicaria gnaphalode, and their rhizosphere soil were determined. The bioconcentration of sodium from soil to roots (BCF), its translocation from roots to shoots (TF), and its accumulation in the shoots (AF) were then calculated. Results showed that the soil of the studied area was clay loam with a high EC of 65 ds/m, indicating its high salinity level. According to the values of sodium adsorption ratio (SAR) and the exchangeable sodium percentage (ESP) and regarding EC, the soil of studied region can be regarded as a saline-sodic soil. The value of TF in some species was higher than 1. However, none of the species had BCF and AF greater than 1, thus, none of them could be considered to be salt accumulator. Instead, it could be assumed that all of the studied species were salt, or at least, sodium excluders.

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Polyploidy induction in German chamomile (Matricaria chamomilla L.) by herbicide trifluralin
 
Leila Karami¹, Mohammad Modarresi², Mohammad Amin Kohanmoo², Fatemeh Zahabi Ahmadi² & Saeed Irian^3
1Department of Horticulture, Faculty of Agriculture and Natural Resources, Persian Gulf University, Bushehr, 7516913817, Iran; ²Department of Plant Breeding, Faculty of Agriculture and Natural Resources, Persian Gulf University, Bushehr, 7516913817, Iran; ³Department of Cell and Molecular Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran.
Correspondent author: Leila Karami, leila.karami@pgu.ac.ir
 
Abstract. Chamomile (Matricaria chamomilla L.) is a medicinal herb belonging to Asteraceae family. This study was conducted to investigate the effect of trifluralin on the induction of polyploidy in chamomile. Two independent full factorial experiments on seedlings and 2-leaf stage apical buds were performed.  Following morphological, biochemical and cytogenetic analysis, chromosome numbers of 18 and 36 were detected for diploid and tetraploid types, respectively. Morphological and biochemical examinations revealed that an increase in the number of full chromosome set results in a reduction in stomata number per unit area as well as an increase in stomata size, chloroplast number, and chlorophyll content. Induction of ploidy level increments also reduced plant height and increased the number of lateral branches, leaf size, and diameters of stems, flowers and receptacles. It is concluded that a concentration of 22.5 µM trifluralin in both methods is optimum for the production of tetraploid chamomile with the highest rate of polyploidy induction and the lowest percentage of abnormality.
 
 

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The aim of this study was to evaluate the antibacterial activity of the water extracts of three species of Salvia (S. perspolitana, S. palaestina, S. bracteata) on Staphylococcus aureus, Escherichia coli and Pseudomonas aeroginosa. The antibacterial activity of water extracts of the studied species on the bacterial strains was examined using well diffusion method and minimum inhibitory concentration (MIC). Results showed that only S. bracteata formed growth inhibitory zone (9 mm) on Staphylococcus aureus. The extracts of all three plants formed growth inhibitory zone on E.coli and P. aeroginosa. The extract of S. bracteata was more effective than that of the other species. Results for MIC also showed that the extracts of S. perspolitana had the lowest effect on St. aureus and its MIC was observed in a concentration of 1024 µg/ml. The extracts of this species had the inhibitory effect in a concentration of 256 µg/ml. The uppermost inhibitory effect was provided by the extract of S. bracteata, since the minimum inhibitory concentration of this species for S. aureus was equal to 64 µg/ml; and for the other two bacteria, it was equal to 128 µg/ml. The extracts of S. palaestina had the lowest effect on S. aureus and its MIC was observed in a concentration of 1024 µg/ml. The extracts of this species had an MIC equal to 512 µg/ml for the other two bacteria. It was concluded that S. bracreata could be considered a suitable species with anti-bacterial activities in future researches.