Showing papers by "Lorestan University published in 2012"

Essential oils composition and antioxidant properties of three thymus species.

Abstract: The essential oils of three wild-growing Thymus species, collected from west of Iran during the flowering stage, were obtained by hydrodistillation and analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC-MS). Under the optimum extraction and analysis conditions, 44, 38, and 38 constituents (mainly monoterpenes compounds) were identified in T. kotschyanus Boiss. and Hohen, T. eriocalyx (Ronniger) Jalas, and T. daenensis subsp lancifolius (Celak) Jalas which represented 89.9%, 99.7%, and 95.8% of the oils, respectively. The main constituents were thymol (16.4–42.6%), carvacrol (7.6–52.3%), and γ-terpinene (3–11.4%). Antioxidant activity was employed by two complementary test systems, namely, 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging and β-carotene/linoleic acid systems. Antioxidant activity of polar subfraction of T. daenensis subsp lancifolius (Celak) Jalas was found to be higher than those of the others in DPPH assay, while nonpolar subfraction of T. eriocalyx (Ronniger) Jalas has most antioxidant activity in β-carotene/linoleic acid test (19.1±0.1 μg/mL and 96.1±0.8% inhibition rate, resp.).

Hermite-Hadamard inequality for functions whose derivatives absolute values are preinvex

Abstract: In this article, we extend some estimates of the right-hand side of a Hermite-Hadamard-type inequality for preinvex functions. Then, a generalization to functions of several variables on invex subsets of is introduced.

Adsorptive removal of methylene blue by agar: effects of NaCl and ethanol

Abstract: Adsorption of methylene blue (MB) on agar was investigated as a function of temperature (308-328 K), different concentrations of NaCl and HCl and various weight percentages of binary mixtures of ethanol with water. It was observed that the maximum experimental adsorption capacity, qm, exp, in water is up to 50 mg g-1 and decreases with increase in weight percentage of ethanol and NaCl and HCl concentration compared to that of water. Analysis of data using ARIAN model showed that MB adsorbs as monomer and dimer on the surface of agar. Binding constants of MB to agar were calculated using the Temkin isotherm. The process is exothermic in water and other solutions. The mean adsorption energy (E) value indicated binding of MB to agar is chemical adsorption. Kinetics of this interaction obeys from the pseudo-second-order model and diffusion of the MB molecules into the agar is the main rate-controlling step.

Oleuropein prevents ethanol-induced gastric ulcers via elevation of antioxidant enzyme activities in rats

Abstract: Purified oleuropein from olive leaf extract has been shown to have antioxidant effects in our recent studies. Thus, the aim of this study was to assess the antioxidant abilities of oleuropein in comparison with ranitidine in ethanol-induced gastric damages via evaluation of ulcer index inhibition, antioxidant enzyme activities, and lipid peroxidation level. Fifty-six adult male Sprague–Dawley rats were divided into seven equal groups as follows: control group, ethanol group (absolute ethanol 1 ml/rat), oleuropein group (12 mg/kg), and oleuropein (6, 12, and 18 mg/kg) plus ethanol groups, as well as ranitidine (50 mg/kg) plus ethanol group. Pretreatment with oleuropein (12 and 18 mg/kg) significantly increased the ulcer index inhibition (percent), in comparison with oleuropein (6 mg/kg). Glutathione peroxidase (GPx) activity was significantly lower in the ethanol group when compared with the other groups whereas, treatment of rats with oleuropein (12 mg/kg) significantly increased glutathione content in gastric tissue when compared with the other groups, and lipid peroxidation was significantly reduced in the oleuropein- (12 and 18 mg/kg) and ranitidine-treated animals. Superoxide dismutase (SOD) and catalase (CAT) activities were both much higher in oleuropein-treated rats than the ethanol group, and although there was a moderate increase in SOD and CAT activities in ranitidine-treated rats, the differences were not significant. These findings suggest that oleuropein has beneficial antioxidant properties against ethanol-induced gastric damages in the rat. Therefore, it seems that a combination regimen including both antioxidant and antisecretory drugs may be beneficial in prevention of ethanol-mediated gastric mucosal damages.

Antioxidant Defense of Betaine Against Oxidative Stress Induced by Ethanol in the Rat Testes

Abstract: Oxidative stress is one of the factors associated with decline in fertility and betaine has been shown to bear antioxidant and methyl donor properties in our recent studies. Thus, we designed the present study to examine antioxidant and methyl donor abilities of betaine in oxidative stress induced by ethanol in the rat testes. The adult male Sprague-Dawley rats were divided into four experimental groups and treated daily for 2 months as follows: control, ethanol (4 g/kg, orally), betaine (1.5 % of total diet, orally), and betaine plus ethanol (betaine, 1.5 % of total diet and after 120 min, ethanol 4 g/kg). Sperm motility and concentration significantly increased in betaine group when compared to the ethanol–treated rats. The main antioxidant enzyme (GPx) activity significantly increased (in order compensatory) in ethanol-treated rats when compared to betaine group while, antiperoxidative enzyme (CAT) activity significantly increased in betaine plus ethanol group as compared to ethanol-treated rats. Total homocysteine (tHcy) and TBARS concentration (as a lipid peroxidation marker) also significantly decreased in betaine and betaine plus ethanol groups as compared to ethanol-treated rats. Overall, methyl donor and antioxidant properties of betaine are promising and reduce the elevated tHcy and TBARS concentrations in betaine plus ethanol group. Therefore, betaine might be used as a potential therapy in hyperhomocysteinemia and oxidative stress induced by ethanol in alcoholism.

Comparison of Headspace Solid‐phase Microextraction, Headspace Single‐drop Microextraction and Hydrodistillation for Chemical Screening of Volatiles in Myrtus Communis L

Abstract: Introduction – Headspace solid-phase microextraction (HS-SPME) and headspace single-drop microextraction (HS-SDME) methods have never been used for the extraction and analysis of the volatile compounds of Myrtus communis. For that reason, in this work, these two techniques were compared with the traditional hydrodistillation (HD) extraction technique. Objective – To compare SPME and SDME with HD for the extraction and analysis of Myrtus communis volatiles. Methodology – Three extraction methods, i.e. SPME, SDME and HD, coupled to gas chromatography-mass spectrometry were used and optimised for the analysis of Myrtus communis volatiles. The SPME extraction was performed on a 100mm PDMS fibre and for SDME a drop of n-octadecane containing 0.7% of menthol as internal standard was used as extracting solvent. The results were compared from different viewpoints including efficiency of extraction, different kinds of species extracted and quantity of extracted compounds with HD. Results – Themain analytes extracted by SPME were found to be a-pinene,limonene,1,8-cineole,linalool,linalylacetate,a-terpinyl acetate and geranyl acetate, whereas for SDME a-pinene, limonene, 1,8-cineole, linalool, linalyl acetate and b-myrcene were extracted as major components. Hydrodistillation could extract a-pinene, limonene, 1,8-cineole, linalool, a-terpineol, linalyl acetate, a-terpinyl acetate, geranyl acetate and cis-isoeugenol better than other volatiles from Myrtus communis. Conclusion – The results demonstrated that HS-SPME and HS-SDME can be applied successfully for the extraction and separation of volatiles in aromatic plants, and these techniques are easier to perform, and more effective than HD for collection of more volatile compounds. Copyright © 2011 John Wiley & Sons, Ltd.

Ghrelin regulates Bax and PCNA but not Bcl-2 expressions following scrotal hyperthermia in the rat.

Abstract: More recently, we have reported the beneficial effects of ghrelin in improvement of histopathological features of the rat testis following local heat exposure. However, the exact mechanism and the precise role of apoptosis- and proliferation-specific proteins in this regeneration process remained to be explored. Thus, thirty adult male Wistar rats were allotted for the experiment and subdivided equally into three groups: control-saline (CS), heat-saline (HS) and heat-ghrelin (HG). The scrota of HS and HG groups were immersed once in water bath at 43 °C for 15 min. HG animals received 2 nmol of ghrelin subcutaneously immediately after heating every other day until day 60 and the other groups were given physiological saline using the same method. The testes of all groups were taken after rat killing on days 30 and 60 after heat treatment for immunocytochemical detection of pro-apoptotic factor Bax, anti-apoptotic protein Bcl-2 and proliferation-associated peptide PCNA in the germ cells. Ghrelin could significantly suppress the Bax expression in spermatocytes compared to the HS group at day 30 ( P P

A new chelation induced enhanced fluorescence-type optical sensor based on parared immobilized in a plasticized PVC membrane for selective determination of Zn(II) ions

Abstract: A new optical sensor based on fluorescence enhancement of a disperse azo dye (parared, PR) immobilized in a plasticized PVC membrane for the determination of Zn2+ ions has been developed. The optode displays a calibration response for Zn2+ ions over the concentration range of 5.0 × 10−3–1.0 × 10−6 M. The response characteristics of the sensor including its response mechanism, membrane composition, pH of solution, repeatability and reproducibility, response time, regeneration and selectivity are discussed in detail. The optode was applied as an indicator electrode in titration of zinc ions and also to the determination of zinc in zinc sulfate tablets and zinc oxide cream.

Quadratic electro-optic effect and electro-absorption process in CdSe–ZnS–CdSe structure

Abstract: The third order nonlinearity susceptibility is obtained as a function of wavelength for CdSe–ZnS–CdSe structure. Numerical calculations show that the quadratic electro-optic and electro absorption effects of this structure depend on the parameters such as structure size, relaxation time and pump photon energy. By changing shells thickness, these structures can be designed with the susceptibility peak from the visible to infrared regions of the spectrum. The intensity and position of the third order nonlinearity susceptibility peaks depend on outer shell thickness and radius of the core.

The effect of ghrelin pretreatment on epididymal sperm quality and tissue antioxidant enzyme activities after testicular ischemia/reperfusion in rats

Abstract: Ghrelin, the endogenous ligand for growth hormone secretagogue receptor, has been reported to prevent ischemia/reperfusion (I/R) injury in various tissues by its antioxidant activity. Therefore, this study was aimed to investigate the effect of ghrelin on sperm quality and antioxidant enzyme activity in a rat testicular ischemia/reperfusion injury model. Forty-two male Wistar rats were divided into groups control, I/R, and I/R plus ghrelin. The right testes were rotated 720° for 1 h and were allowed to reperfuse for 4 h and 30 days thereafter. Ghrelin (40 nmol/kg IP) or vehicle (physiological saline) was administrated 15 min before reperfusion. After 4 h of reperfusion, a right orchiectomy was performed to measure the biochemical parameters. In addition, the sperm was collected from the epididymis after 30 days of reperfusion, and sperm characteristics were examined. The malondialdehyde levels of the testis tissues were significantly increased, but a statistically significant decrease was found in the superoxide dismutase, glutathione peroxidase, and catalase activities in the I/R group as compared with the control, indicating I/R injury. The sperm evaluation showed a significant reduction in all characteristics resulted from I/R compared with the control. In the ghrelin-treated group, the malondialdehyde values were significantly lowered, and only enzyme activity of glutathione peroxidase showed significant increases compared with the I/R group. Ghrelin significantly enhanced sperm motility, movement, and concentration but did not prevent I/R-induced reduction in membrane integrity in the testes of rats compared to the I/R group. Our results suggest that ghrelin treatment has a protective role on IR-induced testicular injury, and this effect may be due to its antioxidant properties.

Effects of Aflatoxin on the Performance of Broiler Breeders and Its Alleviation through Herbal Mycotoxin Binder

Abstract: This study was conducted to investigate the effect of Aflatoxin B 1 (AFB 1) on performance and egg quality in broiler breeders and the abatement of its deteriorative effect through its counteraction with Herbal Mycotoxin Binder (HMB). Thirty-six, 28-wkold broiler breeder hens were allotted to one of the three treatments of: (1) basal diet (control), (2) control plus 500 µg kg -1 AFB 1 and (3) control diet plus 500 µg kg -1 AFB 1+0.2% HMB for three periods, each of a duration of three weeks and when from 28 to 36 weeks of age. Results revealed that 500 µg kg -1 AFB 1 significantly (P< 0.05) reduced feed consumption, feed efficiency, egg production as well as egg weight. Supplementation of HMB partially restored feed consumption and egg production alleviating some side effects of AFB 1.

Cyclodextrin-based dendritic supramolecules; new multivalent nanocarriers

Abstract: Multiarm star copolymers containing a β-cyclodextrin core and poly(2-ethyl-2-oxazoline) arms (CD-POX) were synthesized and characterized. Synthesized CD-POX star copolymers were able to form supramolecular dendritic polymers (SDPs) in aqueous solutions. The ability of SDPs to encapsulate and transfer small guest molecules and also metal nanoparticles was investigated.

Field application of SPME as a novel tool for occupational exposure assessment with inhalational anesthetics.

Abstract: Occupational exposure to inhalational anesthetics occurs routinely in operating rooms. It could induce serious health hazards and diseases. This exposure assessment is a crucial step in determining risks. In this study, a pen-shaped holder for solid-phase microextraction (SPME) sampler was successfully applied as a time-weighted average sampling tool for workshift exposure assessment of operation room staff to halothane. It proved to be very convenient for use in occupational environments such as operation rooms. Samples were analyzed by a gas chromatography–mass spectrometry. The validity of the SPME method was checked in real-world conditions with Occupational Safety and Health Administration (OSHA) 103 standard method for the determination of inhalational anesthetics. A good agreement between OSHA 103 and SPME methods was obtained and results demonstrated no statistically significant differences in anesthetic concentrations determined by the two analytical methods (p ≥ 0.05). It is concluded that SPME in retracted mode could successfully be applied in occupational exposure assessment purposes.

Bending and Shearing Properties of Safflower Stalk

Abstract: The research was conducted in order to determine the bending stress, Young’s modulus, shearing stress, and shearing energy of safflower stalk as a function of moisture content and stalk region. The bending forces were measured at different moisture contents and the bending stress and the Young’s modulus were calculated from these data. For measuring the shear forces, the stalk specimens were severed by using a computer aided cutting apparatus. The shear energy was calculated by using the area under the shear force versus displacement curve. The experiments were conducted at four moisture contents (8.61, 16.37, 25.26, and 37.16% wb) and at three stalk regions (bottom, middle, and top). Based on the results obtained, the bending stress decreased as the moisture content increased. The value of the bending stress obtained at the lowest moisture content was approximately 2 times higher than that of the highest moisture content. Bending stress values also decreased from top to the bottom of stalks. The average bending stress value varied from 21.98 to 59.19 MPa. The Young’s modulus in bending also decreased as the moisture content and diameter of stalks increased. The average Young's modulus varied between 0.86 and 3.33 GPa. The shear stress and the shear energy increased with increasing moisture content. Values of the shear stress and energy also increased from top to the bottom of stalks due to the structural heterogeneity. The maximum shear stress and shear energy were found to be 11.04 MPa and 938.33 mJ, respectively, both occurring at the bottom region with the moisture content of 37.16%.

Hermite–hadamard type inequalities for functions when a power of the absolute value of the first derivative is p-convex

Abstract: In this paper we extend some estimates of the right-hand side of a Hermite–Hadamard type inequality for functions whose derivatives’ absolute values are P-convex. Applications to the trapezoidal formula and special means are introduced.

Noncovalent interactions between linear-dendritic copolymers and carbon nanotubes lead to liposome-like nanocapsules

Abstract: Morphology (conformation) of carbon nanotubes was changed from extended- toward closed-state upon noncovalent interactions with polyglycerol-poly(ethylene glycol)-polyglycerol ABA type hydrophilic linear-dendritic copolymer and liposome-like nanocapsules were formed. Since one of the proposed reasons for the carcinogenicity of carbon nanotubes is their long lengths and rigid structures, flexible liposome-like nanocapsules prepared by this strategy could be safer and far from the asbestos-like physicochemical properties of CNTs and therefore their potential health hazards. Avoiding these health hazards, it is possible to develop CNTs for biomedical applications. Therefore biocompatibility of liposome-like nanocapsules and their ability to load and deliver anticancer drugs such as doxorubicin was evaluated and it was proved that their loading capacity is more that two grams of drug to one gram of liposome-like nanocapsules.

A Study on the Seed Susceptibility of Wheat (Triticum aestivum L.) Cultivars to Impact Damage

Abstract: Mechanical damage due to harvesting, handling, and other processes is an important factor that affects the seeds quality. Seed damage results in lower grain value and more storability problem and reduces seed germination and seedling vigor and subsequent yield of crops. Tests were conducted to determine the percentage of physical damage (PPD) and percentage of loss in germination (PLG) of wheat seeds due to impact. The effect of wheat seed cultivar and impact velocity was determined. Wheat seed cultivars selected for testing included: Kohdasht, Maron, Simereh, Sardari and Zagros. Four impact velocities: 10, 20, 30 and 40 m s -1 were used. Results showed that effects of impact velocity and seed cultivar on seed damages were significant. PPD to seeds was higher than PLG in higher impact velocities. It found that the total damage of seeds increased from 4.17% (0.48 PPD and 3.68 PLG) to 73.32 % (47.59 PPD and 25.73 PLG) as impact velocity increased from 10 to 40 m s -1 for all wheat cultivars studied. Impact results indicated that Sardari wheat cultivar was more susceptible to PPD (27.39 %), while Maron seeds were more susceptible to PLG (14.70%). Among the cultivars studied, Sardari wheat seeds showed the highest level of total damage i.e.sum of PPD and PLG.