Chemoprotective effects of carnosine against genotoxicity induced by cyclophosphamide in mice bone marrow cells

The protective effects of carnosine as a natural dipeptide were investigated in mouse bone marrow cells against genotoxicity induced by cyclophosphamide. Mice were injected with solutions of carnosine at three different doses (10, 50 and 100?mg kg(-1) bw) for five consecutive days. On the fifth day of treatment, mice were injected cyclophosphamide and killed after 24?h. The frequency of micronuclei in polychromatic erythrocytes and the ratio of polychromatic erythrocyte/polychromatic erythrocyte?+?normochromatic erythrocyte [PCE/(PCE?+?NCE)] were evaluated by May-Grunwald/Giemsa staining. Histopathology of bone marrow was examined in mice treated with cyclophosphamide and carnosine. Carnosine significantly reduced micronucleated polychromatic erythrocytes (MnPCEs) induced by cyclophosphamide at all three doses. Carnosine at dose of 100?mg kg(-1) bw reduced MnPCEs 3.76-fold and completely normalized the PCE/(PCE?+?NCE) ratio. Administration of carnosine inhibited bone marrow toxicity induced by cyclophosphamide. It appeared that carnosine with protective activity reduced the oxidative stress and genotoxicity induced by cyclophosphamide in bone marrow cells of mice. Copyright ? 2012 John Wiley & Sons, Ltd.     

Interaction of iron nanoparticles with nervous system: an in vitro study

Nanoparticles (NPs) are one of the interesting and widely studying issues mainly because of their particular physico-chemical features and broad applications in the field of biomedical sciences, such as diagnosis and drug delivery. In this study, the interaction of iron nanoparticles (Fe–NPs) with Tau protein and PC12 cell, as potential nervous system models, was investigated with a range of techniques including dynamic light scattering, intrinsic fluorescence spectroscopy, circular dichroism, [(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium-bromid] assay, and acridine orange/ethidium bromide (AO/EB) dual staining method. An inverse correlation between Stern and Volmer constant (K_SV) and temperature indicated a probable static quenching mechanism occurred between Tau protein and Fe–NPs. The number of binding site (n = 0.86) showed that there is almost one binding site of Fe–NP per protein. The negative values of ?H (?53.21 kJ/mol) and T?S (?42.44 kJ/mol) revealed that Fe–NPs interacts with Tau protein with dominate role of hydrogen bonds and van der Waals interactions and this interaction was spontaneous (?G = ?10.77 kJ/mol). Also, Fe–NPs stabilized the random coil structure of Tau protein. Moreover, Fe–NPs reduced PC12 cells viability by fragmentation of DNA in an apoptotic manner. In conclusion, induced conformational changes of Tau protein and cytotoxicity of PC12 cells by Fe–NP were revealed to be in a concentration and time-dependent manner.     

Widespread distribution of Beet necrotic yellow vein virus in Iranian sugar beet industry

Beet necrotic yellow vein virus (BNYVV) is the most devastating pathogen of sugar beet worldwide. This virus has been reported in the majority of sugar beet growing regions of Iran as well. For the present study, we collected samples from different sugar beet varieties with suspected symptoms of BNYVV from the main important sugar beet growing regions in eight provinces of Iran. Infection of collected samples to BNYVV was tested by ELISA and RT-PCR. Upon testing of 167 collected samples of BNYVV suspected through ELISA and RT-PCR, 115 (68.9%) were infected. Different incidences of BNYVV through surveyed provinces may represent the presence of diverse infective viral sources or resistance genes in tested sugar beet varieties which need further attempts to develop control strategies. Results also showed that BNYVV has been recently distributed throughout some surveyed regions. Otherwise, trace infection or resistance to BNYVV infection in some varieties of distinct regions may represent proper sources of resistance to BNYVV.     

Detection of adulteration in Iranian saffron samples by <Superscript>1</Superscript>H NMR spectroscopy and multivariate data analysis techniques

Introduction

The high market value of saffron (Crocus sativus L.) has made it an attractive candidate for adulteration. Safflower (Carthamus tinctorius L.) and tartrazine are among the most common herbal and synthetic foreign materials that may be added to pure saffron for the purpose of adulteration. In spite of encouraging advances achieved in the identification of adulteration in saffron samples, the lack of a simple method with sufficient power for discrimination of pure high grade saffron from meticulously adulterated saffron samples persuaded us to perform this study.

Objectives

In this work, we show that ¹H NMR spectroscopy together with chemometric multivariate data analysis methods can be used for the detection of adulteration in saffron.

Methods

Authentic Iranian saffron samples (n?=?20) and adulterated samples that were prepared by adding either different quantities of natural plant materials such as safflower, or synthetic dyes such as tartrazine or naphthol yellow to pure saffron (n?=?22) composed the training set. This training set was used to build multivariate Principal Component Analysis (PCA) and Partial Least Squares Discriminant Analysis (PLS-DA) models. The predictive power of the PLS-DA model was validated by testing the model against an external dataset (n?=?13).

Results

PCA and PLS-DA models could both discriminate between the authentic and adulterated samples, and the external validation showed 100% sensitivity and specificity for predicting the authenticity of suspicious samples. Peaks specific to authentic and adulterated samples were also characterized. Proximity of samples with unknown adulteration status to the samples adulterated with known compounds in the PCA provided insight regarding the identity of the adulterant in the suspicious samples. Furthermore, the authentic samples could be distinguished based on their cultivation site.

Conclusion

The present study demonstrates that the application of ¹H NMR spectroscopy coupled with multivariate data analysis is a suitable approach for detection of adulteration in saffron specimens. Outstanding sensitivity and specificity of the PLS-DA model in discriminating the authentic from adulterated samples in external validation confirmed the high predictive power of the model. The advantage of the present method is its power for detecting a wide spectrum of adulterants, ranging from synthetic dyes to herbal materials, in a single assay.

     

Multispectroscopic studies on the interaction of a copper(ii) complex of ibuprofen drug with calf thymus DNA

The interaction of copper(II)–ibuprofenato complex with calf thymus DNA (ct-DNA) has been explored following, UV-visible spectrophotometry, fluorescence measurement, dynamic viscosity measurements, and circular dichroism spectroscopy. In spectrophotometric studies of ct-DNA it was found that [Cu(ibp)₂]₂ can form a complex with double-helical DNA. The association constant of [Cu(ibp)₂]₂ with DNA from UV-Vis study was found to be 6.19 × 10⁴ L mol^?1. The values of K_f from fluorescence measurement clearly underscore the high affinity of [Cu(ibp)₂]₂ to DNA. The experimental results showed that the conformational changes in DNA helix induced by [Cu(ibp)₂]₂ are the reason for the fluorescence quenching of the DNA-Hoechst system. In addition, the fluorescence emission spectra of intercalated methylene blue (MB) with increasing concentrations of [Cu(ibp)₂]₂ represented a significant increase of MB intensity as to release MB from MB-DNA system. The results of circular dichroism (CD) suggested that copper(II)–ibuprofenato complex can change the conformation of DNA. In addition, the results of viscosity measurements suggest that copper(II)–ibuprofenato complex may bind with non-classical intercalative mode. From spectroscopic and hydrodynamic studies, it has been found that [Cu(ibp)₂]₂ interacts with DNA by partial intercalation mode which contains intercalation and groove properties.     

PDADMAC as a flocculant for lignosulfonate of NSSC pulping process

The spent liquor (SL) of neutral sulfite semi‐chemical (NSSC) pulping process contains about 8 wt% lignocelluloses that can be extracted and used in the production of value‐added materials. In this work, a flocculation process followed by centrifugation was considered for isolating lignosulfonate and hemicelluloses from SL. It was observed that, by adding 20 mg/g of polydiallyldimethylammuniom chloride (PDADMAC) with 100,000–200,000 g/mol molecular weight to SL, 45% of lignosulfonate and 39% of hemicelluloses were removed at 30°C. The lignocellulose removal was more efficient for the dual flocculation system of low and high molecular weights PDADMAC than for individual PDADMAC systems. Overall, 49% of lignosulfonate, 47% of hemicelluloses and 97% of turbidity were removed from SL from the dual system when 10 mg/g low molecular weight PDADMAC and 10 mg/g high molecular weight PDADMAC were added to the SL at 30°C, subsequently. The thermogravimetric analysis (TGA) of generated flocs showed that all samples had similar thermal behaviour and 13–16 wt% of flocs remained as ash after burning at 700°C in nitrogen. As the flocs are made of lignocellulosic materials and they are thermally stable, they could be used as fillers in paper board production. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:686–691, 2016     

Design,Synthesis, and Molecular Docking of Some Novel Tacrine Based Cyclopentapyranopyridine- and Tetrahydropyranoquinoline-Kojic Acid Derivatives as Anti-Acetylcholinesterase Agents

A novel series of tacrine based cyclopentapyranopyridine- and tetrahydropyranoquinoline-kojic acid derivatives were designed, synthesized, and evaluated as anti-cholinesterase agents. The chemical structures of all target compounds were characterized by ¹H-NMR, ¹³C-NMR, and elemental analyses. The synthesized compounds mostly inhibited acetylcholinesterase enzyme (AChE) with IC₅₀ values of 4.18–48.71 μM rather than butyrylcholinesterase enzyme (BChE) with IC₅₀ values of >100 μM. Among them, cyclopentapyranopyridine-kojic acid derivatives showed slightly better AChE inhibitory activity compared to tetrahydropyranoquinoline-kojic acid. The compound 10-amino-2-(hydroxymethyl)-11-(4-isopropylphenyl)-7,8,9,11-tetrahydro-4H-cyclopenta[b]pyrano[2′,3′ : 5,6]pyrano[3,2-e]pyridin-4-one ( 6f ) bearing 4-isopropylphenyl moiety and cyclopentane ring exhibited the highest anti-AChE activity with IC₅₀ value of 4.18 μM. The kinetic study indicated that the compound 6f acts as a mixed inhibitor and the molecular docking studies also illustrated that the compound 6f binds to both the catalytic site (CS) and peripheral anionic site (PAS) of AChE. The compound 6f showed moderate neuroprotective properties against H₂O₂-induced cytotoxicity in PC12 cells. The theoretical ADME study also predicted good drug-likeness for the compound 6f . Based on these results, the compound 6f seems to be a very promising AChE inhibitor for the treatment of Alzheimer's disease.