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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.

 

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The aim of this study was to investigate the interaction modification of curcumin complex molecule (CUR) in beta- and gamma-cyclodextrin (β-CD and γ-CD) carriers with chitosan (CS) nanoparticles for targeted drug delivery and to compare their performance. The targeted drug delivery system includes the therapeutic agent of the CS nanoparticles targeting section of the same drug and the CD carrier system. Calculations of the relationships of the formation of modified complexes and their application were performed using UV-vis spectroscopic data analysis. In this study, spectroscopic spectrum diagrams were drawn to prove the optimization of molecular structure in the modified complexes. Data analysis was performed using their respective equations. The cationic polysaccharide CS, with the presence of amino agents and alcohols along the polysaccharide chains, enables it to form a covalent bond with the complexes and increase the solubility of cyclodextrin. CS nanoparticles strengthen the hydrogen bond by hydrogen bonding and van der Waals hydrogen interactions of the hydroxyl cyclodextrin group with the hydroxyl phenolic group of the drug molecule CUR. Modification of the γ-CD complex with CS shows the strongest interaction with CUR. Both CUR complexes are in the CD-CS host system to transfer the charge from the drug to the carrier and the therapeutic agent. CS nanoparticles have the property of targeted delivery systems for anticancer drugs because the CS external field can be used to direct the drug to specific target cells. The γ-CD-CS host system is the best host as a carrier and therapeutic agent for CUR due to its high solubility and strong interaction.
 
 

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Seaweed extract can improve the physicochemical properties of the soil and has a favorable effect on the plant growth and development due to having high nutrient content, high water holding capacity, plant growth regulators and beneficial microorganisms. The aim of this experiment was to investigate the effect of Ascophyllum nodosum extract, a brown alga, on the morphophysiological characteristics of bean plant (Phaseolus vulgaris) under water stress. The experiment was performed in a Completely Randomized Factorial Design with three replications. Experimental treatments included 4 concentrations of foliar application of seaweed extract (0, 0.2, 0.4 and 0.6%) and 3 levels of water stress including no stress, mild stress and severe stress (irrigation at 75, 50 and 25% of field capacity, respectively). The results showed that the interaction effects of stress and algal extract on the evaluated traits were not significant. However, the seaweed extract significantly increased the leaf area, number of the leaves, leaf length, surface and length of the roots, root dry weight, the content of chlorophyll a and b and the total chlorophyll content. Application of algal extract at levels of 0.2 and 0.4% caused a significant increase in the evaluated parameters as compared with the control plants. The evaluation of water scarcity stress effects showed a significant reduction in the all studied characteristics in accordance with increasing water stress level from 75% to 25% of field capacity. The results of this study showed that foliar application of seaweed extract significantly increased some morphological and photosynthetic properties, while water stress significantly reduced the investigated parameters.

 

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Seyed Mohammad Ali Shariatzadeh & Zahra Alizadeh
Department of Biology, Faculty of Sciences, Arak University, Arak, Iran
Correspondent author: Seyed Mohammad Ali Shariatzadeh, s-shariatzadeh@araku.ac.ir

Abstract. Silver nanoparticles (Ag NPs) can affect female fertility because they can cause toxicity in the ovaries. The aim of this study is to see if Spirulina platensis (SP) can protect mouse from Ag NPs-exposed toxicity in its ovary. Twenty-four female Naval Medical Research Institute (NMRI) mice were divided into four groups (n = 6 per group): control; Ag NPs (500 mg/kg daily); SP (300 mg/kg daily) and Ag NPs + SP (With the same defined doses). 30 days after oral gavage treatment, biochemical parameters were measured and ovary compartments were estimated stereologically. The Ferric Reducing Antioxidant Power (FRAP) values, hormonal concentrations, corpus luteum volume, and the number of healthy follicles were all significantly lower (p<0.05) in the Ag NPs group compared with the control group. in the SP group, malondialdehyde concentration and atretic follicles were significantly lower (p<0.05) compared with the control group. There was no significant difference in the mean total volume of ovary, cortex, medulla, oocyte and its nucleus, and the thickness of the zona pellucida in any group. Although, SP in the Ag NPs + SP group cannot compensate the above parameters to the control level, it considerably improves ovarian damage caused by Ag NPs through reducing oxidative stress.

Key words. follicles, hormones, oxidative stress, stereology, zona pellucida

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Rana Valizadeh Kamran¹, Lamia Vojodi Mehrabani², Ali Aryan¹ & Alireza Tarinejad^1
1
Corresponding author: Rana Valizadeh Kamran, rana.valizadeh@gmail.com

Abstract. Bioremediation is a promising strategy to reduce the concentration of heavy metals that their increase in the soil was the result of the development of industries and factories in the area, threatening the environment and human health. To investigate the effect of the heavy metal chromium and the reduction of its toxic effects by bacteria (at two levels of the absence of bacteria and the presence of bacteria in Hoagland's solution), a factorial experiment was conducted as a completely randomized design with three replications and the morphological, physiological traits and plant elements were measured in the applied treatments. The results showed that the experimental treatments did not affect plant yield traits, fresh weight, stem length, and leaf length. Leaf width, chlorophyll a, b, and plant phosphorus content decreased under chromium stress and increased with bacterial treatment. Hydrogen peroxide, malondialdehyde, ascorbate peroxidase, superoxide dismutase, catalase, proline, solid soluble substances, phenol, flavonoid, and anthocyanin, as well as the content of plant elements such as chromium, nitrogen, and potassium, increased due to the chromium treatment. Using bacteria in the culture medium containing chromium, significantly decreased the hydrogen peroxide and malondialdehyde, indicating a reduction in the oxidative stress. The non-enzymatic and enzymatic antioxidants of plats in the bacterial treatments increased, indicating bacteria's role in strengthening the plant's antioxidant system. The chromium content of the plant decreased after the use of bacteria. The results showed the positive effect of using chromium-purifying bacteria in the environment of plant cultivation in reducing the harmful effects of chromium heavy metal stress.