BACKGROUND AND OBJECTIVES: Disinterred manures from dumpsites in the cities are believed to be readily available source for soil nutrient for backyard farming. Health hazards posed on human due to Labile metals contaminants are not considered or evaluated before consumption. Three major municipal dumpsites from Okitipupa (Waste Management (OKA), Igodan(OKB), and Okitipupa Oil Mill Road (OKC)) were analyzed for the concentrations, forms of Labile metals in the soil and also concentration in green vegetables from the sites. The objectives of the research were to investigate the Labile metal concentration, forms of the Labile metals in the soil and their accumulation in plants from these major urban dumpsites. METHODS: Dried and digestedSoil and vegetable samples from the sites were analyzed for total concentration of Labile metals and their forms through speciation in the soil were equally quantified. Concentrations from sample solutions were determined by Atomic Absorption Spectrophotometer. FINDINGS: Labile metals concentrations from the soilof Waste Management Dumpsite (OKA), IgodanDumpsite (OKB) and Okitipupa Oil Mill Road Dumpsite (OKC) indicated that Cadmium (Cd) values range from87. 453mg/kg-106. 500mg/kg). Copper (Cu) in the three samples ranged between 3. 100-5. 510mg/kg, which are significantly low and beyond the toxicity level as well as cobalt (Co). Chromium (Cr) was higher in OKA (22. 980mg/kg) and OKC (10. 560mg/kg) and least in OKB (2. 900mg/kg). Iron was the most abundant ranging from 3690. 000-6780. 000mg/kg, followed by zinc ranging from385. 000-2880. 000mg/ kg. Speciation of the Labile metal indicate that the metal exist mostly in the inert fraction and easily absorbed by plant. CONCLUSION: The concentrations of the most Labile metals in soil samples were high and majorly exist in inert fraction after speciation. Also, the concentrations in the plants were almost half of the concentration in the soil which indicated that they are not desirable for human consumption due to their toxicity level.

Introduction and objective: The appearance of resistance to anti-tuberculosis drugs has generated research to find new and more effective drugs. Lowenstein-Jensen medium (LJ) is frequently used for culturing strains of Mycobacterium tuberculosis. A group of antimicrobial substances used in treating tuberculosis is sensitive to heat and cannot be used on LJ medium. Research now aims to setup a modified method for evaluation of heat Labile drugs in LS medium.Materials and methods: In this study, we investigated culturing M. tuberculosis for 48h on Middle brook 7H9 broth medium with antituberculosis drugs and re culturing on LJ medium (without antibiotic) and incubating for 40 days.Results: Our results after 48h of contact of the strains with antibiotic were comparable with the standard method of culture on Middle brook 7H10 agar medium containing antibiotic. Therefore, 48h is a suitable time for primary contact between mycobacterium and heat Labile antibiotics.Conclusion: This modified method can be applied to LJ medium instead of expensive Middle brook 7H10 agar medium for evaluation of heat Labile anti tuberculosis drugs.

Background and Objective: Enterotoxigenic Escherichia coli (ETEC) are the most common agent which causes diarrhea, worldwide. ETEC is colonized along the cells and then producing heat-Labile (LT) and heat-stable enterotoxigenic which enter into intestinal epithelial cells and causes water and electrolyte loss from intestinal epithelial cells and eventually cause diarrhea.This study was done to detect the heat-Labile toxin in Enterotoxigenic Escherichia coli using PCR-ELISA technique.Methods: In this descriptive study, DIG-labeled PCR products were bounded to streptoavidin-coated wells of a microtiter plate and detected by anti-DIG–peroxidase conjugate. The biotin-labeled internal probe was used for verification of PCR products.Results: Heat-Labile toxin was detected by PCR-ELISA method. The sensitivity of heat-Labile toxin was 1.9 ng. This method did not cross-react with bacteria from this variety.Conclusion: PCR-ELISA method is 100 times more sensitive than conventional PCR method and due to lack of agarose gel and electrophoresis device it can be a good alternative to traditional method.

Background and objectives: Decrease in natural forests area in north of our country due to various factors has caused the importance of reclaimed forest in this area which is carried out with the aim of developing forest surface and wood production. Therefore, study the nature of plantations can play an important and effective role in creating forests with better quality and quantity in the future. The forest plantation stands can effect on different litter and soil indicators. Various researches showed different types of broadleaves and needle leaves trees that are widely used in forestry have very different characteristics in the quality of the soil organic inputs. However, the role of Fraxinus excelsior, Quercus castaneifolia, Picea Abies and Pinus nigra species on litter and soil characteristics from the perspective of the quality indices and Labile organic matter fractions, have not been studied. The purpose of this research was to study the litter quality and Labile organic matter fractions in the forested areas of the Hyrcanian region, which is affected by the effect of Fraxinus excelsior, Quercus castaneifolia, Picea Abies and Pinus nigra on the characteristics of organic and mineral layer of soil. Materials and methods: For this purpose, 40-years-old afforestation stands including Fraxinus excelsior, Quercus castaneifolia, Picea Abies and Pinus nigra species were selected and 8 litter and soil (25×25×15cm) samples were collected under each of stands. Collected samples of litter and soil were transferred to the laboratory for analysis, and the physical, chemical and Labile components of soil organic matter were investigated. Results: of the most litter nitrogen content (1. 37%) and the least of litter carbon content (40. 51%), C/N ratio (33. 10) and litter thickness (8. 05%) were found under Fraxinus excelsior. Soil physical and chemical properties (except for bulk density, silt and clay contents) were significantly differences between tree species. Results showed that the soil under Pinus nigra had the highest values of particulate organic C (4. 52 g/kg) and dissolved organic C (125. 36 mg/kg). Greater amounts of particulate organic N (0. 36 g/kg) and dissolved organic N (28/66 mg/kg) were belonged to Fraxinus excelsior soil. Soil N mineralization was significantly higher under Fraxinus excelsior (39. 97 mg/kg) and Quercus castaneifolia (35. 40 mg/kg) than in Picea Abies (26. 85 mg/kg) and Pinus nigra (19. 53 mg/kg). Conclusion: The findings of this research are indicating that the characters related to C are enhanced by needle-leaved trees, while broad-leaved stands improved the features related to N content. Results showed broadleaved species increased soil fertility regarding to better quality of litter.

During the past 50 years, the amount of agricultural fertilizer used in Northern China increased from about 7.5 kg ha-1 in the 1950s to approximately 348 kg ha-1 in the 1990s. Given that little is known about the effects of nitrogen fertilization on soil Labile carbon fraction in Northern China, this paper evaluated such effects in terms of microbial biomass and dissolved organic carbon in the Sanjiang Plain located in Northeast China. Soils with different cultivation time and undisturbed marsh with Deyeuxia angustifolia were selected to study the effects of nitrogen fertilization on the soil Labile organic fractions microbial C (biomass C, microbial quotient, and basal respiration) and to estimate the contributions of nitrogen input on the dynamics of soil Labile carbon. Continuous nitrogen application decreased total organic and dissolved organic carbon concentrations significantly, leading to the lack of carbon source for microbes. Therefore, continuous nitrogen fertilizer application induced negative effects on measured soil microbiological properties. However, a moderate nitrogen application rate (60 kg N ha-1) stimulated soil microbial activity in the short term (about 2 months), whereas a high nitrogen application rate (150 kg N ha-1) inhibited measured soil microbiological properties in the same period.