Sesquiterpenes compounds are well known biogenic volatile organic compounds. They play important roles in atmospheric process since they are reactive and have high yields in the formation of secondary organic aerosol which in turn, reduces visibility by scattering the light, becomes cloud condensation nuclei and affects the radiation balance, and impairs human health because of its toxicity. There has no report on the sesquiterpenes (SQT) contribution to the atmosphere from ambient fungal species. Quantitative and qualitative characterization of SQT is essentially needed for a better understanding and assessment on the role of ambient fungi as natural or biological source of SQT....[ Read more ]

Sesquiterpenes compounds are well known biogenic volatile organic compounds. They play important roles in atmospheric process since they are reactive and have high yields in the formation of secondary organic aerosol which in turn, reduces visibility by scattering the light, becomes cloud condensation nuclei and affects the radiation balance, and impairs human health because of its toxicity. There has no report on the sesquiterpenes (SQT) contribution to the atmosphere from ambient fungal species. Quantitative and qualitative characterization of SQT is essentially needed for a better understanding and assessment on the role of ambient fungi as natural or biological source of SQT.

Six common airborne fungi (Aspergillus niger, Cladosporium sp., Penicillium Chrysogenum, Penicillium sp. (A), Penicillium sp.(B) and Trichoderma sp) were selected in this study. They were inoculated in Malt Extract Agar (MEA) plates and incubated in Andersen impactor. Air samples flowing through the fungal culture were collected with Tenax thermal desorption tubes and sesquiterpenes were analyszed with gas chromatograph and mass spectrometric detector coupled with an Automated Thermal Desorber. A total of twenty-four sesquiterpene species were identified. The amount and composition of the sesquiterpene emitted by the model species, Trichoderma sp., was found to be species-, temperature-, RH- and face velocity-dependent. The emission rate also depends on the growth rate. The steady sesquiterpenes emission of Aspergillus niger, Cladosporium sp., Trichoderma sp, Penicillium Chrysogenum, Penicillium sp. (A) and Penicillium sp.(B) were determined as 1.09 μg, 0.36 μg, 2.22 μg, 0.63 μg, 1.00 μg and 1.2021μg per day, respectively. The emission rate is comparable with one fifth to one tenth of reported vegetation emission. Fungi can thus be a high potential sesquiterpene emission source.