A b s t r a c t : Thiram, a dithiocarbamate fungicide, i s electrochemically active on glassy carbon electrodes in an aqueous medium. An amperometric method developed under optimized conditions produces smooth and reproducible responses, yielding linear calibration curves with a minimum detection limit of 1 . 0~1 0 .~ M, based on the signal-to-noise ratio (SIN) of 3. Application of t h i s methodology for t h e determination of Thiram in water leachates, collected a t various time intervals from a laboratory prepared soil bed, results in reliable results. Additionally, the amount of Thiram in an agricultural bean seed sample is well quantified using this methodology, thus demonstrating the applicability of the proposed amperometric method in real sample analysis. NMR and UV-visible spectroscopic methods confirm the presence of Thiram in the seed sample.K e y W o r d s : amperometry, cyclic voltammetry, dithiocarbamate fungicide.

Immobilization of macro molecules (such as enzymes) and microorganisms can be generally defined as a procedure leading to their restricted mobility. Advantages of immobilization include easy separation of the enzymes/cells from the product and reuse of the enzymes/cells. In this research coconut tree leaf sheath was used to immobilize selected microbes which were used in fermentation tecnology. Coconut tree leaf sheath contains cellulose fiber layers which have cross linking between them. Sacchromyces cerevisiae was used as the microbial type due to widespread use in fermentation process. Microbes were entrapped within cellulose layers. Coconut tree leaf sheath was found to be an effecient solid support for immobilization. Immobilized microbes can be reused for fresh fermentation media. Immobilization can be carried out utilizing naturally avavilable coconut tree leaf sheath as a solid support, it`s usage is very cost-effective and eco-froiendly method rather than using synthetic or semi synthetic solid supports.

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Bio fuel is one of the emerging industries around the world due to arise of crisis in petroleum fuel. Fermentation is a cost effective and eco-friendly process in production of bio-fuel. One major problem in microbial ethanol fermentation is the low resistance of conventional microorganisms to the high ethanol concentrations, which ultimately lead to decrease in the efficiency of the process. In the present investigation, an ethanol resistant bacterium was isolated from sap of Saccharum officinarum (sugar cane). The optimal cultural conditions such as, temperature, incubation period, and microbiological characteristics, morphological characteristics, biochemical characteristics, ethanol tolerance, sugar tolerance were investigated. Isolated microorganism was tolerated to 18% (V/V) of ethanol concentration in the medium and 35% (V/V) glucose concentration in the medium. Biochemical characteristics have revealed as Gram negative, non-motile, negative for Indole test, Methyl Red test, Voges-Proskauer`s test, Citrate Utilization test, and Urease test and positive results for Oxidase test. Sucrose, Glucose, Fructose, Maltose, Dextrose, Arabinose, Raffinose, Lactose, and Sachcharose can be utilized by this particular bacterium. It is a significant feature in effective fermentation. The fermentation process was carried out in glucose medium under optimum conditions; temperature 30°C, and incubated for 72 hours. Maximum ethanol production was recorded as 12.8±0.4% (V/V). Methanol was not detected throughout the fermentation process. This bacterium is especially useful in biofuel production due to high ethanol tolerance of this microorganism; it can be used to enhance the fermentation process over conventional microorganisms. Investigations are currently conducted on establishing the identity of the bacterium.