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  • The identification of phylloquinone in cattle samples using T.L.C. method
    75-78
    Views:
    73

    A case of hemorrhage of unknown origin was observed in cattle and liver samples were submitted for assay of Vitamin K or
    possible cuomarol. After evaluating normal and reverse phase Thin Layer Chromatography (TLC) plates and different solvents,
    reverse phase TLC plate with indicator and methylene chloride:methanol 70:30 were chosen for direct method of detection and
    indication of Vitamin K.Gass Chromatography and Densitometry were used to quantitate the Vitamin K present in liver samples and
    confirmation of Vitamin K was done by Mass Spectroscopy.

  • GC-MS studies to map mechanistic aspects of photolytic decomposition of pesticides
    11-16
    Views:
    78

    Transformation of pesticides in the environment is a highly complex process affected by different factors. Both biological and physical-chemical factors may play a role in the degradation, whose ratio depends on the actual environmental conditions.
    Our study aims to reveal specific details of photolytic degradation of pesticides as important soil contaminants. Significance of these studies is enhanced by the fact that pesticide decomposition may contribute to soil degradation, and have harmful biological effects by degrading to toxic products. The toxicity of the examined pesticides is well known, however very little information is available regarding their natural degradation processes, the quality, structure and biological impact of the degradation products.
    The photolytic degradation of frequently applied pesticides of distinctive types (acetochlor – acetanilide, simazine – triazine, chlorpyrifos – organophosphate, carbendazim – benzimidazole) was investigated. A special, immerseable UV-light source was applied in order to carry out photodegradation. The degradation processes were followed by thin layer chromatography (TLC) and mass spectrometry coupled with gas chromatography (GC/MS). EI mass spectrometry was used to identify the degradation species.
    Each of the studied pesticides underwent photolytic decomposition, and the detailed mechanism of photolytic transformation was established. At least four degradation species were detected and identified in each case. Loss of alkyl, alkyloxy, amino-alkyl and chloro groups might be regarded as typical decomposition patterns. Deamination occurred at the last stage of decomposition.

  • Testing of Various Solvents for the Preparation of Lipid Samples for Use in Thin Layer Chromatography
    49-50
    Views:
    66

    We analyzed the muscular tissue of 6 sheep. Lipid extraction was performed using the Handson and Olley method. TLC separation was performed using 4 separation systems and the best separation method was determined. Visualization was done using a mixture copper acetate and phosphoric acid, at 150 oC.

  • Determination of conversion rate values to characterise the ethanol production of the Kluyveromyces marxianus CBS712 fungus branch
    23-27
    Views:
    69

    The ethanol production of the Kluyveromyces marxianus CBS712 strain was investigated among different kind of condition. We defined the conversion rate in order to know the efficiency of the ethanol production. To determine this value, it is crucial to characterize the residual glucose concentracio. We chose two method to determine the amount of residual glucose. The first method is the thin layer chromatography (TLC) and the second method is the method of the glucose-oxidase enzyme. We found that the TLC method is reliable than the other method. The conversion rates were determined from these values and the ethanol values. The maximal ethanol production of the characterized Kluyveromyces marxianus CBS712 strain (5.6% (v/v) ethanol at 45 °C, 55.3% conversion rate) is comparable to those strains which are applied in industrial ethanol production nowadays.