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The research reported the biogenesis of hydrocarbon gases form the bituminous coal by moderately barophilic methanogens of coal mine water adjacent to underground aquifer and gas reservoir site of Barapukuria coal basin. Physiochemical characteristics of the coal (with zero gas baseline) as carbon source (Seam VI , 390 m depth) for methanogens are determined. Parameters include inherent moisture content, volatile matter, ash content, calorific value, fixed carbon, α factor , H / C ratio , CHNSO elemental composition analysis, spectral assignments of ATR-FTIR, aromaticity factor f a and degree of aromatic ring condensation ( R / C ) u . Heavy, minors & light elements of calcined coal are also determined by X-ray fluorescence. Moderately barophilic methanogens surviving 5.61–6.45 MPa lithostatic pressure (taking Barapukuria coal average specific gravity 1.43) are identified by fluorescence at ultraviolet region (100–400 nm) of electromagnetic radiation and AQG-1 Methanometer. Bluish white fluorescence at UV is due to the redox coenzyme F 350 in methanogens. Fluorescence at 350 nm excitation is bluish white. The methanogens only have the ability to produce gas in presence of coal which acts as an electrode surface to take up electron for hydrogenase and other enzymes for formation of hydrocarbon gases. They also have the coal biodegradability. The methanogens yielded methane, ethylene, ethane, propane, iso-butane as detected by flame ionization detector of Bruker 450 gas chromatograph.

Barapukuria Coal Mine situated in the district Dinajpur. Bangladesh is playing an important role in the economy of this country by the mining of top quality coal. With coal mining, mine waste is also generated called coal spoil. Coal spoil can impose environmental threat if not treated carefully. In contrast, it can also be converted to value added product. In the present work, coal spoils collected from Barapukuria coal mine drainage water were investigated to determine the quality of the samples by physico-chemical analysis (proximate and ultimate analysis) as well as by heating value determination. 50% of carbon was detected in the samples after elemental analysis, with sulfur content less than 0.4%. Calorific value around 9300 btu/lb was obtained for the coal spoil. Moreover, moisture content, ash, volatile matter content and fixed carbon also provided fruitful information regarding the quality and economic prospect of the samples in comparison to the quality of Barapukuria coal.

Four hydrazones (HZs) and six semicarbazones (SCZs) of substituted benzaldehydes were synthesized and examined for their ability to control insect adenylate cyclase through their interaction with biogenic amine receptors. Among the compounds synthesized, two with a hydroxyl group at the 4-position of the phenyl moiety, HZ-01 and SCZ-03, were found to reduce the basal levels of cAMP in head membrane homogenates of fifth instar larvae of the silkworm Bombyx mori. The semicarbazone SCZ-03 dose-dependently attenuated not only basal but also forskolin-stimulated cAMP levels. Tyramine (TYR) and dopamine (DPM) also produced a dose-dependent reduction in basal cAMP levels. DPM and TYR receptor antagonists abolished the attenuating effects of SCZ-03. These findings suggest that SCZ-03 acts as a non-selective agonist for DPM and TYR receptors to inactivate adenylate cyclase in B. mori larvae.

Tyramine (TA), a biogenic amine, attenuates intracellular cAMP production by acting on its receptor in insects. Several non-biogenic amines were examined for their actions on native and heterologously expressed silkworm TA receptors. 5-(4-Hydroxyphenyl)oxazole, which showed an attenuating effect on cAMP production in silkworm-head membranes, did not attenuate forskolin-stimulated cAMP production in HEK-293 cells expressing the silkworm TA receptor, although the compound bound to the cloned receptor. 2-Phenylethylamines (2-PEAs), which showed positive and negative effects on cAMP production in silkworm-head membranes, inhibited [3H]TA binding to the cloned TA receptor. 2-Chloro-2-(4-chlorophenyl)ethylamine was the most potent inhibitor of [3H]TA binding among the 2-PEAs tested, with an IC50 of 30.4 nM. This compound acted as an antagonist and abolished TA-attenuation of forskolin-stimulated cAMP production in the cloned TA receptor. The discrepancy in the effects of the non-biogenic amines on the native and cloned TA receptors remains to be further examined. A newly synthesized 2-PEA, 2-chloro-2-(4-hydroxyphenyl)ethylamine, attenuated forskolin-stimulated cAMP production in the cloned TA receptor, indicating that the para-hydroxy group is important for the agonist action.

Octopamine (OCT)/tyramine (TYR) analogues, mainly including p- and β-substituted phenylethylamines, were prepared as probes for the ligand-binding site(s) of adenylate cyclase-coupled OCT or TYR receptors, and were examined for their effects on cAMP production in the head membranes of Bombyx mori larvae. Small structural changes in OCT and TYR proved to lead to three types of OCT/TYR analogues: (1) compounds that increase the cAMP level by themselves and also depress OCT-stimulated cAMP production, (2) compounds that do not stimulate cAMP production by themselves but inhibit OCT-stimulated cAMP production, and (3) compounds that are not active in either the stimulation of cAMP production or the inhibition of OCT-stimulated cAMP production. Tyramine, which belongs to the second group, also inhibited the basal level of cAMP production at high concentrations. The data indicate that two biogenic amine systems that positively and negatively regulate the level of the second messenger cAMP are present in the head part of B. mori larvae. This finding points to the necessity of separately evaluating the positive and negative regulatory effects in order to quantitatively understand the structure-activity relationships of OCT receptor ligands. Arch. Insect Biochem. Physiol. 47:1–7, 2001. © 2001 Wiley-Liss, Inc.