In the present study, the optimization of im-mobilization structures along with Calothrix sp. and the determination of heavy metals absorption rate have been investigated. Polymers in combination with salts were performed in alginate in order to study the stability of formed structures in cross linking agents. Beads with stable structure in synthesized heavy metal solution inoculated and the adsorption percentage has been recorded. Results showed that the most stable beads were formed in 2 and 3% alginate along with CaCO3 application beside BaCl2 as solidified solution. Reduction of heavy metal in these structures had the most percentage and it was observed that if the incubation time of beads in solidified solution decreased, the percentage of heavy metal reduction would increase to 86%. Although alginate beads showed the highest absorption rate of heavy metal, the presence of Calothrix sp. in all treatments occasionally increased heavy metal absorption up to 15%.

Biosurfactants have the ability to form heavy metal complexes and clean up heavy metal contaminated soils. In this work, a biosurfactant producing bacterium (Bacillus spp.) isolated from compost and Pseudomonas aeuroginosa ATCC3027 were cultured in whey in order to produce biosurfactant. Compost samples were leached by supernatant of mentioned strains. Total amount of Pb, Ni, Cr, Cd, Zn, Cu and Mn in samples were measured before and after treatment was measured. It was revealed that supernatant of P. aeuroginosa ATCC 3027 removed 52, 49, 60, 33, 25, 32 and 22% of Pb, Ni, Cr, Cd, Zn, Cu and Mn respectively. Heavy metal removal by supernatant of strain B was 45, 39, 42, 33, 40, 41 and 29% for above mentioned metals; respectively. These results indicate the potential of the biosurfactants as leaching agents for heavy metal removal from compost.

Background: Rice is one of the most important agricultural products and main food for more than %25 people in the world. Due to increasing consumption of this product, evaluation of quality and characteristics of cultivated rice in different regions of country is of great importance. Additionally, over the past decades, heavy metals contamination in rice cause to be public concern, thus assessment of heavy metal pollution of rice is necessary. Evaluation the characteristics of rice varieties will allow consumers and producers to prepare rice according to their taste and need. Therefore, this study was conducted to evaluate the amount of lead and cadmium, physicochemical properties and cooking quality of champa rice in different regions of Baghmalek, Khuzestan.Materials and Methods: In this study, rice cultivated in different regions of Baghmalek was sampled in three replications and transferred to the laboratory for testing. Physicochemical tests including protein, moisture content, ash, total solid, amylose content and thousand grain weight were evaluated based on national standard of Iran. Cadmium and lead content of rice cultivated in different region of Baghmalek were evaluated. Cooking properties of studied rice including cooking time, water absorption, leakage, gelatinization grade and Elongation of rice were evaluated. The tests were performed in a completely randomized design with SAS software and analyzed by Duncan test at a probability level of 5%.Results: The results of proximate test including (carbohydrate, protein, total solid, ash and moisture) showed that significant difference was between samples cultivated in different region of Baghmalek. In all samples, except for one samples, amylose content were 20-21%. The results of heavy metal evaluation indicated Cd in all samples were in permissible limit but lead content in imported rice and cultivated rice in Sidon and Meydavoud was more than permissible limit. Studied samples with regard to lenght were in medium category and Elongation of rice was in the range of 1.39-1.74. The gelatinization grade of studied samples was in the range of 3.25-4.17. Evaluation of cooking properties including cooking time, water absorption and leakage indicated it was significant difference between studied samples. Thousand grain weight of studied samples had been significant difference and was in the range of 13.07-18.86.Conclusion: In general, selected rice samples from different regions of Baghmalek exhibited a significant difference in physicochemical properties. With regard to cooking properties and quality, rice samples had desirable status and were comparable to imported rice. Evaluation of the safety status of studied rice samples suggests that control of cultivated regions is necessary.

The removal of copper (II), zinc (II), and chromium (III) from wastewater by carrot residues (CR) was investigated to evaluate cation exchange capacity. The effects of solution pH and co- ions were studied in batch experiments. Adsorption equilibria were initially rapidly established, and then decreased markedly after 10 min. Column experiments were carried out in a glass column filled with CR to evaluate the metal removal capacity. The influences of the feed concentration and feed rate were also studied in order to compare the dynamic capacity for metal binding in different feed concentrations.