Journal of Chemical Health Risks
Volume:4 Issue: 4, Autumn 2014

Wheat flour is a commodity with a high risk of aflatoxins (AFs) contamination. During the bread making there are many processes that can affect the AFs stability. The effect of bread making process using different yeast types on AFs levels was investigated. For this purpose, standards of AFs including B and Gwere added to flour and then bread loaves were prepared. Three types of commercially available yeast including active dry yeast, instant dry yeast and compressed yeast were used for dough preparation. AFs levels in flour, dough, and bread were analyzed by high performance liquid chromatography (HPLC) with fluorescence detector. The results showed that maximum reduction in aflatoxin levels observed during first proof while the least decline was seen for the baking stage. The order of AFs reduction in bread making process was AFB1>AFB2>AFG1. Furthermore, the results indicated that the most effective yeast for AFs reduction was instant dry yeast.

In this study, the essential oil obtained by hydrodistillation of the seed of Trachyspermum ammi (Umbelliferae), growing wild in Sabzevar, Khorasan Razavi province (Iran), were analyzed by GC and GC/MS. The yield of total volatiles was 2.3% (w/w). Forty four compounds representing 91.6% of the aerial parts oil were identified. The main components of the oil were Hexadecanoic acid (27.5%), ethyl linoleate (8.5%), 6-methyl-α-ionone (8.0%), isobutyl phthalate (5.8%), α-cadinol (4.7%), germacrene D (4.3%) and δ-cadinene (3.5%). The oil was rich in nonterpenoids (56.0%). The total flavonoid content of different extracts of the plant was found to be in the range 53.2-164.5 mg/g while the maximum amount concern to methanol extract. The antioxidant activity of the extracts was also measured by radical scavenging activity of antioxidants against free radical 1, 1-diphenyl-2-picrylhydrazyl (DPPH) method. Results showed that IC50 of the extracts of Trachyspermum ammi seed are higher than the standard synthetic antioxidants, BHT, ascorbic acid and gallic acid.

A simple spectrofluorimetric method is described for the determination of doxorubicin (DXR) based on its quenching effect on the fluorescence intensity of Tb3+- deferasirox (DFX) complex as a fluorescent probe. The excitation and emission wavelengths were 328 and 545 nm, respectively. The effects of pH, time, order of addition of reagents, concentrations of Tb3+ and DFX and the buffer volume on the quenched fluorescence intensity were investigated and optimized. In the optimum conditions, the decrease of the fluorescence intensity of the system showed a good linear relationship with the concentration of DXR in the range of 20-1000 μg L-1, with a correlation coefficient 0.998. The detection limit (3s) was 6.1 μg L-1 and the relative standard deviation for four replicate determinations of different concentrations of DXR was in the range of 1.7–4.4%. The procedure was successfully applied to the determination of doxorubicin in urine and serum samples

The effects of zinc oxide nanorod (ZnO-N) incorporation on thephysicochemical properties of tapioca starch / bovin gelatin composite film such as water absorption capacity (WАC), water solubility and permeability to water vapour (WVP) were investigated. In this search, ZnO-N was homogenized by sonication and added into tapioca starch / bovine gelаtin dispersions аt different concentrations (e.g. 0.5, 2, and 3.5% w/w total solid). Incorporation of 3.5% of nanoparticles to tapioca starch / bovine gelatin films decreased the permeability to water vapor by 18%. Water absorption capacity and Solubility of the films were decreased by increasing the ZnO-N contents. These properties suggest that ZnO-N has the potential as filler in starch /gelatin-based films for using in pharmaceutical and food packaging industries

This study was mainly designed to investigate and identify the amounts and types of heavy metals in the soils of National Iranian Oil Refining & Distribution Company in Shahrood region and tried to establish a logical relation between the presence of heavy metals and their damage on vegetation. In addition, considering the power of drained soil and due to the proximity of ground water in Shahrood region, conducting this study provides a better insight into recognition of the possible contamination centers of drinking waters. The gridding and selective method was used for sampling step. Accordingly, five sub-samples were taken from each grid and finally after mixing all of the sub-samples, the final samples were obtained with an average weight of 400 grams prior to sending to the laboratory. To determine the total concentration of heavy metals in soil, extraction was done using concentrated solutions of HCl and HNO3. The total concentration of the heavy metals of chromium, cobalt and nickel were measured using an ICP-MS instrument, and the rest of the elements using an XRF device. The results explicitly indicated that the quantities of nickel, lead, zinc and strontium in patient samples exceeded the standard, and the other elements were lower than their standard limits. More specifically, the contents of lead and strontium in both normal and patient samples were higher than their standard contents. Moreover, the majority of the vegetation loss across the affected areas was caused by heavy metal accumulation, particularly nickel, lead, zinc, and strontium.

Melamine is a potentially hazardous compound and one of the major concerns especially in dairy products and pet foods. In the present study a sensitive, simple and reliable method for extraction and determination of melamine in infant milk and coffee mate has been developed. This method consists of an initial extraction in buffer media prepared by formic acid and sodium formate, followed by protein precipitation by acetonitrile and dichloromethane. The chromatographic separation was carried out on a 100-Nucleosil -NH2 column with an optimized acetonitrile-water (80:20 v/v) as a mobile phase and with a photodiode-array detector. The analytical method was validated according to the validation parameters, such as, selectivity, linearity (0.08-10 µg/mL, with r2= 0.9998 and 0.05-10 µg/mL with r2= 0.9997), precision (intra-day 0.52-2.66%, 0.78-1.20; inter-day 2.96-4.20%, 2.80-3.00%) and accuracy (92-102%, 92-100%) for powdered milk and coffee mates respectively. The limits of detection and quantization were 0.02, 0.08 µg/mL for powdered milk and 0.01, 0.05 µg/mL for coffee mate, respectively.

The present study aimed to use a method for the synthesis of some 3, 4-dihydropyrimidin-2-(1H) - ones/thiones. The study tried to answer the question whether this reaction can be performed without solvent and with new catalyst or not. To find answer to the question, we described a novel protocol for the efficient synthesis of 3, 4-dihydropyrimidin-2-(1H)-one derivatives using aromatic aldehyde, ethylacetoacetate, and urea/thiourea under solvent-free conditions by using SiO2-CaCl2as acatalyst. Using this catalyst has some advantages; it''s high yields, usable in mild conditions, available, reusable, ecofriendly, cost effective and environmentally friendly. The structural features of the synthesized compounds were characterized by IR, 1H NMR and 13C NMR. The compounds were screened for antimicrobial activity. The results showed these compounds react against all the tested bacteria. We have demonstrated a novel method for the synthesis of substituted dihydropyrimidinones catalyzed by SiO2-CaCl2 under solvent-free conditions.

The aim of this study was to evaluate the physiological and morphological characteristics of Narcissus tazatta in response to benzyl adenine (BA) and nano-potassium fertilizer. This experiment was done as factorial with two factors of benzyl adenine hormone and nano-potassium fertilizer in a completely randomized design with ten replications. Benzyl adenine in four levels (0, 500, 750 and1000 ppm) and nano-potassium in three levels (0, 1.5 and 2.5 gr/l) were applied as spraying the solution on plants. Results showed significant effect of benzyl adenine hormone on water absorption rate and the number of flowers in 1% probability level (P<0.05). Besides, the effect of different levels of fertilizer on water absorption rate, diameter of the stem, length of stem, wet and dry weight of the flower and the number of flowers was significant. The maximum diameter of the stem was obtained with 1.5 gr/l nano-potassium fertilizers. In the interaction between hormone and fertilizer, maximum concentration of antocyanin was seen by 750 ppm BA and 2.5 gr/l nano-potassium with an average e of 0.6 µg in a gram of wet weight of the plant. The highest water absorption rate was obtained through the application of 2.5 gr/lit nano-potassium and 500 ppm BA. Therefore, the results of this experiment indicate that hormone and fertilizer of nano-potash cause to increase quality of flower.