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Background and purpose : Chromium deficiency leads to impaired glucose and lipid metabolism. Chromium supplementation in type II diabetic patients improves glucose and lipid profiles. Organic chromium, such as found in brewer’s yeast, is much better absorbed than inorganic chromium. In this study, the effect of chromium supplementation in the form of brewer’s yeast on glucose and lipid profile of diabetic patients were evaluated.
Materials and methods : In a clinical trial study (before and after) forty (32 women and 8 men) dyslipidemic diabetic patients without liver and cardiovascular diseases, 40-68 years old and BMI ³ 28 were randomly selected. Each patient received brewer’s yeast tablets containing 14.4 microgram chromium per day for 4 and 8 weeks. Fasting blood glucose, total cholesterol, HDL-C, LDLC and triglycerides were measured at the beginning and the end of 4 and 8 weeks after consumption of brewer’s yeast. A 24 hr dietary recall before and 4 and 8 weeks after consumption of brewer’s yeast were analyzed using Nutrition III software. Data were compared using paired t-test and x2-test as appropriate.
Results : There were no statistical significant changes in body weight, BMI, energy and macronutrient intake before and after brewer’s yeast tablet. Mean total cholesterol (p<0.05) and fasting blood sugar levels (p<0.04) were significantly decreased after 8 weeks consumption of brewer’s yeast tablets. Mean LDLC and triglyceride level were significantly (p<0.001) decreased after 4 and 8 weeks consumption of brewer’s yeast tablets. Mean HDLC level was significantly (p<0.001) increased after 4 and 8 weeks consumption of brewer’s yeast tablets. An negative relationship was found between total cholesterol, LDLC, HDLC and TG of primary concentration and percentage of changes during study for each parameters.
Conclusion : Improved glucose and lipid profile was noted in patients following 4 and 8 weeks consumption of brewer’s yeast tablets containing 14.4 microgram chromium per day. Also low chromium levels in diabetic patients,prevents diabetic patient from cardiovascular disease.

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Background and purpose: According to thetheory ofsustainable development, protect the environmentforcurrent and futuregenerationsisinevitable. Chromium (VI) is one of the pollutant of waterthatcauseharm totheaqueous environmentandrisksfor human health, animalsand plants. The purpose of this study was tosynthesis of Fe3O4 nanoparticlesand evaluateofCr (VI) adsorptionon Nanoparticle ssynthesizedasanadsorbent. Materials and methods: Inthisexperimental- laboratorystudy, nanoparticleswere synthesized bychemicalco-precipitation method and as an adsorbent was studiedforadsorptionof Cr (VI).The resulted nanomaterials were characterized by SEM, XRD and FT-IR. Effects ofpH, contacttime, adsorbentdoses andinitial Cr (VI) concentration werestudied. The resulting data were described by the Langmuir and Freundlich isotherm models and for Data analysis was used from Excel software. Results: The results showedthat thecharacterization ofnanoparticleswereas expectedandthe best of removal performance in pH= 2, at contact time equal10 min, adsorbentdose of 1g/L and initial Cr (VI) concentration of50 mg/L.The Pattern of Cr (VI) adsorption was fitted with the Freundlich model and Adsorption processes followed the pseudo second-order kinetics. Conclusion: chemical co-precipitation Synthesis methodbased onlow power consumptionandShort time isaappropriate methodandFe3O4nanoparticlessynthesizedby this methodcan be used as asuitable optionfor theadsorptionof Cr (VI).

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Background and purpose:As the usage of chromium in chemical industries, electroplating, leather tanning and paint processes will increase, so the chromium pollution in water has become a considerable problem. Hexavalent chromium (Cr (VI)) has been reported toxic to aquatic organisms, animals and humans. It has been known to be carcinogenic. Thus, it should be removed from wastewater before discharge to the environment directly. Photocatalyst process is one of advanced technologies in removal of organic and inorganic pollutants from water and wastewater.The aim of this study was the use of photocatalytic removal of (Cr (VI) using ZnO nanoparticles as catalyst in a batch reactor Material and Methods:In this experimental study, at first commerical ZnO nanoparticle was prepared. A point of zero charge, pHpzc, of nanoparticle was obtained using batch equilibration method. In this study, different experimental conditions such as initial Cr (VI) ion concentration (10 to 50 mg•L-1), pH (3 to 9) and nanoparticle loading (0.1 to 1gr) at various contact time (0 to 120min) and one UV irradiation intencityhave been evaluated. In addition, kinetic models involve in the photocatalic removal of Cr (VI) were investigated. Chromium (VI) concentration was determined colorimetrically at 540nm using the 1,5-diphenylcarbazide (DPC) method with detection limit of 5mgL-1 using the UV–vis spectrophotometer (Shimadzu, Japan). Results: The pHZPC for ZnO was 7.51. The obtained results showed that the removal efficiency of Cr (VI) increased with an increasing ZnO nanoparticles loading. The Cr (VI) removal percentage decreased as the initial Cr (VI) concentration increased. The maximum removal of Cr (VI) was obtained at acidic pH (86.65% for pH=3 vs. 42.55% for pH=9). Kinetic analysis of the photoreduction showed the removal of Cr (VI) is according to the Langmuir–Hinshelwood (L–H) model (R2=0.995) and the adsorption of Cr (VI) on the ZnO nanoparticle surfaces may be the controlling step in the entire reduction process. Conclusion: This study results showed UV/ZnO was an effective method in the removal of hexavalent chromium from aqueous solutionsand maybe UV/ZnO process applied in Cr (VI) removal in low concentration and acidic pH, effectively.

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Background and purpose: Mushrooms are highly nutritive, since they are low in calories and contain significant amounts of vegetative proteins, vitamins, minerals, amino acid, and fiber. Mushrooms might be contaminated by heavy metals such as lead, cadmium, chromium, etc. This contamination depends on type of mushrooms, their physiology, and ecosystem. The present study aimed at determining the amount of lead, cadmium and chromium in edible mushrooms disturbed in the city of Sari (north of Iran). Material and methods: This study was done in laboratory on 108 samples of commercial mushrooms widely found in supermarkets in Sari. They were coded 1 to 6 and their stem and cap were studied. Finally, the amount of lead, cadmium, and chromium were determined using atomic absorption spectrometer (AAS). Results: The concentrations of lead and cadmium were found to be less than standard levels recommended by Codex guidelines. But the amount of chromium in all samples was observed to be more than Codex standards (20 mg/kg). The Provisional Tolerable Weekly Intake (PTWI) for chromium in cap was similar to standard levels while this was lower in stem. Conclusion: High concentrations of chromium could be due to high levels of that found in composts used for growing mushrooms or contaminated water.

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Background and purpose: Presence of heavy metals in water resources is of great concerns due to adverse effects on human health. The aims of this study were to evaluate the efficiency of coagulation process using Polyaluminum Silicate Chloride (PASiC) in removal of hexavalent chromium and Cadmium from aqueous solutions and comparing that to the standards.

Materials and methods: Experiments were carried out by Jar test using PASiC coagulant. The applied pH range in this study was 4 to 11, and different PASiC dosage (15 to 187.5 mg/l), heavy metal concentrations (5 to 100 mg/l), and settling times (10 to 90 minutes) were investigated. All experiments were repeated three times for accuracy and precision.

Results: The optimum conditions for chromium removal was in PASiC dose of 150 mg/l, pH= 5, and settling time= 45 minutes, which decreased the chromium concentration (from 10 mg/l initial concentration) to 3.118 ± 0.29 mg/l and this was more than the standard levels of wastewater discharge into receiving water. The PASiC in 75 mg/l could reduce the cadmium level to 0.019 ± 0.01 mg/l (from 5 mg/l) in optimum condition (pH= 8 and settling time= 30 minutes). This level of cadmium removal was less than the standard levels of wastewater discharge into the receiving water.

Conclusion: The PASiC coagulant was found to be more effective in removing cadmium than chromium from aqueous solutions and could be applied for cadmium removal from water and wastewater.

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Background and purpose: Chromium hexavalent compounds are carcinogens that are found in groundwater as chromate and dichromate negative ions. The aim of this study was to remove Cr (VI) from water by activated carbon modified with cationic surfactant alkyl dimethyl benzyl ammonium chloride (Benzalkonium chloride).

Materials and methods: In terms of the Critical Micelle Concentration (CMC) of surfactant, three concentrations of Benzalkonium Chloride (BZK) including  half, one  and two fold of CMC were used to modify activated carbon.  Modification was performed by contacting activated carbon and surfactant  for 24h on the shaker. Ordinary and modified activated carbons were used as sorbents for Cr(VI) removal from aqeoues solutions. Modified Activated Carbon (MAC) by cationic surfactant and Unmodified Activated Carbon (UAC) were examined as adsorbents for Cr (VI) from aqueous solutions. Experiments were conducted in batch and continuous mode in acid (pH=4), natural (pH=7) and alkaline conditions (pH=10). Cr (VI) was measured by spectrophotometer.

Results: Time to reach Cr (VI) adsorption equilibrium for UAC and MAC were 180 and 120 min, respectively.  Cr (VI) adsorption capacity for UAC was 1.79 mg/g but in MAC the value increased to 8.87 mg/g. 5g/L of MAC modified with 2cmc of surfactant showed greatest Cr (VI) adsorption capacity in natural pH condition. Breakthrough point in the column packed with MAC enhanced 3 times compared with UAC. Adsorption isotherm was best fitted with Langmuir model and adsorption kinetics was determined as pseudo second order.

Conclusion: Modification of activated carbon by cationic surfactant causes increase in adsorption capacity of Cr (VI) from aqueous solution. Therefore, it could be used in removal of toxic Cr (VI) compounds from water.