The cyanobacterium Pseudanabaena sp. FACHB 1277, a 2-methylisoborneol (2-MIB) producer isolated from Xionghe Reservoir, was identified by molecular biological methods based on the 16S rDNA sequence. Pseudanabaena sp. FACHB 1277 is a planktonic freshwater species with relatively high 2-MIB per cell density value (7.76 x 10(-6) ng cell(-1)) and specific growth rate (0.25 +/- 0.01 d(-1)). The effects of temperature and light intensity on 2-MIB production of Pseudanabaena sp. FACHB 1277 were investigated. Of the six temperatures tested, 10, 15, 20, 25, 30, and 35 A degrees C, the maximum total 2-MIB per cell density and minimum cell density were observed at 10 A degrees C, while the total 2-MIB and dissolved 2-MIB (including extracellular and dissolved intracellular 2-MIB) increased with increasing temperature. Among the six tested light intensities (10, 25, 40, 55, 70, and 85 mu mol photons m(-2) s(-1)), the minimum total 2-MIB per cell density and maximum cell density were observed at 25 mu mol photons m(-2) s(-1). The total 2-MIB and extracellular 2-MIB increased with light intensity increasing from 10 to 40 mu mol photons m(-2) s(-1), while no significant increase was observed when the light intensity was higher than 40 mu mol photons m(-2) s(-1). The maximum intracellular 2-MIB (including dissolved and bound) occurred at 25 mu mol photons m(-2) s(-1). The present study indicates that increasing temperature could favor the conversion of bound intracellular to dissolved 2-MIB, while increasing light intensity stimulates the release of dissolved intracellular 2-MIB into the environment.
; GEOSMIN PRODUCTION
; ODOROUS COMPOUNDS
; LAKE BIWA
National Natural Science Foundation of China-Israel Science Foundation(41561144008)
; National Natural Science Foundation of China(31000183)