Two neolignan compounds, magnolol (5,5'-diallyl-2,2'-dihydroxybiphenyl, 1) and honokiol (5,5'-diallyl-2,4'-dihydroxybiphenyl, 2), were isolated from the stem bark of Magnolia obovata and evaluated for antifungal activity against various human pathogenic fungi. Compound 1 and 2 showed significant inhibitory activities against Trichophyton mentagrophytes, Microsporium gypseum, Epidermophyton floccosum, Aspergillus niger, Cryptococcus neoformans, and Candida albicans with minimum inhibitory concentrations (MIC) in a range of 25-100 microg/ml. Therefore, compound 1 and 2 could be used as lead compounds for the development of novel antifungal agents.

With no confident emission information, a dynamic multimedia model (POPsME) was evaluated by comparing predicted and measured relative concentrations (defined as the ratio of concentration in a medium to that in soil) for 12 polycyclic aromatic hydrocarbons (PAHs) (phenanthrene, anthracene, fluoranthene, pyrene, chrysene, benz[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-c,d]pyrene). Field monitoring for multimedia (air particulates, water (dissolved phase and suspended solids), soil, sediment, and leaves of Pinus koraiensis and Prunus serrulata) was conducted seasonally over 1 yr from August 1999 to July 2000 at seven sites in Seoul and neighboring areas (150 km × 150 km) in Korea. The model was calibrated using the monitoring data of four PAHs (phenanthrene, pyrene, benzo[a]pyrene, and benzo[g,h,i]perylene) and tested with the remaining eight PAHs. For C suspended   solids/C soil and C sediment/C soil (Ci , concentration (mol/m3) in medium i), the model prediction changed with octanol−water partition coefficient (K ow) from underestimation to overestimation, revealing a limitation to the use of sorption equilibrium assumption and/or K ow for the description of sorption. Nonetheless, the model prediction generally agreed with the measured within a factor of 10 for all the monitored media. The relative concentration was shown to be a useful means to evaluate and improve the model.

A multimedia mass balance model (MMM), POPsME, was evaluated for its performance to assess the fate and transport of 2,3,7,8-substituted PCDD/Fs in Seoul and a neighboring area (150 km x 150 km) in Korea. As part of the evaluation, the effects of the grid size with the homogeneous mixing assumption were estimated on the sign and magnitude of the prediction bias. The prediction compared with the monitoring data generally within 1 order of magnitude. In the presence of a concentration gradient within individual cells of 30 km x 30 km,the prediction bias for air and soil tended to increase with the distance from the sources. It was observed that the ratio of the predicted to the measured values could vary more than 4 times with the location of the monitoring site. Use of the large grid size in POPsME (and perhaps other MMMs) resulted in overpredictions for a major portion of the model domain at the cost of underprediction for limited areas nearthe sources. Beyond the source areas, a substantial contribution of the total prediction bias originated from the congeners with a large atmospheric loss rate and small TEF value. On a TEQ basis, therefore, the magnitude of the overpredictions could be significantly reduced as compared to that of the underprediction for the source areas.

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