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Background and Objective: In recent years, management and disposal of municipal solid waste has become a global problem and the most important environmental concern. Anaerobic digestion is a cost-effective solution for treatment of both solid waste and wastewater. The aim of this study was to investigate the positive or negative effects of calcium chloride content in anaerobic digestion process of municipal solid waste and leachate on biogas production. Materials and Methods: Experiments with 8 levels of calcium chloride on co-digestion of municipal solid waste and leachate were investigated in 500 ml digesters under mesophilic conditions in a completely randomized design with three replications. Reactors with a ratio of substrate to inoculum of 2 (on VS basis) were operated and the volume of the biogas was measured daily. Volatile and total solids, carbon/nitrogen of waste, COD, BOD and heavy metals were measured by following APHA. Results: The results of the experiment showed that the pH was decreased with increasing calcium chloride concentration. The highest amount of cumulative biogas production was obtained in CaCl2 of 2 g/L with the highest VS and TS reduction. Higher concentrations of CaCl2 (≥3 g/L) caused a reduction in the degradability of volatile and total solids and, as a result, a decreased performance of the digester. Conclusion: The results clearly confirmed that the addition of calcium chloride was an effective solution to improve biodegradability in co-digestion of the MSW and leachate and consequently to reduce the total and volatile solids and to increase the amount of‌ biogas.

Background and Objective: The anti inflammatory, analgesic, antioxidant of Sambucus ebulus L. have been reported in several studies. This study was done to assess the repelling property of the methalonic and hexanic extracts of Sambucus ebulus L. against the Culex pipiens. Methods: In this experimental study, Sambucus ebulus L. collected from the natural inhabitants of Mazandran province in northern Iran. Methalonic and hexanic extraction were provided from the leaf and fruit of Sambucus ebulus L. Concentration of 50 mg/kg, 100 mg/kg and 250 mg/kg was prepared. 0.4 ml of the extract prepared and was spreed on the albino skin area of 4×6 cm2. After 30 minutes the number of the mosquito (Culex pipiens) bites on the skin was recorded. N, Ndiethyl-3 methyl benzamide was considered as positive control. Results: The highest repelling property of the Sambucus ebulus L. belonged to the concentration of 250 mg/kg of leaf and fruit extraction. The highest repelling effect was 80% and 66.8% for leaf methalonic and hexanic extract, respectively. The highest repelling effect was 84% and 72% for fruit metalonic and hexanic extract, respectively (P

Abstract Background & aim: Anti-oxidant compounds prevent prevalence of chronic diseases and food spoiling. The aim of this study was to evaluate the total phenolic and flavonoid content and antioxidant activity of beech and oak barks. Methods: In this experimental study, the skin of beech and oak trees were prepared and then acetone extraction was obtained using Soxhle method. At the beginning, total phenol and flavonoid of extracts were determined and the anti-oxidant properties of the extracts were then evaluated by three methods (methods Biphenyl Pykryl Hydrosol, regenerative power produced- and nitric oxide). Results: The amount of phenolic was higher in bark of beech trees, but flavonoids were higher in oaks. The result of test to trap free radicals of Biphenyl Pykryl Hydrazyl showed the inhibitory concentration 50% of acetone extract of the bark of beech and oak, were 92.19 and 33.7 mg/L respectively. Beech extracts had greater regenerative power than oak. In Nitric oxide trap test acetone extract inhibited 50% in bark of beech trees was 98/23 and the oak extract was 92/90 mg/L respectively. Conclusion: Acetone extract of the bark in three models showed varying degrees of anti - oxidant activity. Beech extract had better antioxidant activity compared with oak extract. Key words: Anti-oxidant Activity, Phenols, Flavonoids, Beech, Oak