• Natural Product Sciences
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• v.6 no.2
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• pp.102-105
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• 2000

Chemical investigation of the hot hexane extract of the stem bark of Gordonia dassanayakei afforded a new oleanane triterpenoid, $11{\alpha},13{\beta}-dihydroxyolean-3,12-dione$ (1) and two other oleanane triterpenoids, $3{\beta}-acetoxy-11{\alpha},13{\beta}-dihydroxyolean-12-one\;(2)\;and\;3{\beta},11{\alpha}-diacetoxy-13{\beta}-hydroxyolean-12-one\;(3)\;and\;a\;hopane\;6{\alpha},22-diol$ (4), which are new to the plant.

• Journal of Microbiology and Biotechnology
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• v.13 no.3
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• pp.437-443
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• 2003

Bioremediation technologies were applied to experimental microcosms, simulating an oil spill in a lower intertidal area. Three treatments (oil only, oil plus nutrients, and oil plus nutrients and microbial inocula) were applied, and each microcosm was repeatedly filled and eluted with seawater every 12 h to simulate tidal cycles. To minimize washing-out of the inoculum by the tidal cycles, microbial cells were primarily immobilized on diatomaceous earth before they were applied to the oiled sand. Oil degradation was monitored by gravimetric measurements, thin layer chromatography/flame ionization detector (TLC/FID) analysis, and gas chromatography (GC) analysis, and the loss of oil content was normalized to sand mass or nor-hopane. When the data were normalized to sand mass, no consistent differences were detected between nutrient-amended and nutrient/inoculum-amended microcosms, although both differed from the oil-only microcosm in respect of oil removal rate by a factor of 4 to 14. However, the data relative to nor-hopane showed a significant treatment difference between the nutrient-amended and nutrient/inoculum-treated microcosms, especially in the early phase of the treatment. The accelerating effect of inoculum treatment has hardly been reported in studies of oil bioremediation in the Tower intertidal area. The inoculum immobilized on diatomaceous earth seemed to be a very effective formulation for retaining microbial cells in association with the sand. Results of this study also suggest that interpretation of the effectiveness of bioremediation could be dependent on the selection of monitoring methods, and consequently the application of various analytical methods in combination could be a solution to overcome the limitations of oil bioremediation monitoring.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.3
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• pp.238-246
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• 2012

Once oil is spilled into marine environment, it experiences various weathering processes among which evaporation is the most dominant process in the initial stage of weathering. This study aimed to elucidate the effects of evaporation on the physicochemical properties of spilled oil using standardized laboratory experiments. Laboratory evaporation process was successfully reproduced using controlled rotary evaporation method. In case of Iranian Heavy crude (IHC), evaporation rate after 48 hours was $29.3{\pm}0.4%$ (n=40, p<0.001). Evaporation was simulated using ADIOS2 weathering model and the result was in agreement with laboratory experiment. Chemical composition changes of petroleum hydrocarbons including alkanes, polycyclic aromatic hydrocarbons (PAHs) and biomarkers by evaporation rate were also analyzed. As oil evaporated, low molecular weight alkanes and PAHs decreased, while biomakers showed conservative characteristics. Among biomarkers, $17{\alpha}(H)$, $21{\beta}(H)$-hopane was used for calculation of weathering rates, which matched with evaporative mass losses. Weathering rate calculation using hopane showed that stranded oils of weathering stage I (28.9%) and mesocosm oil weathering experiment till 5 days (26.5%) were mainly affected by evaporation process.