Long chain alkenes, alkenones and alkenoates produced by the haptophyte alga Chrysotila lamellosa CCMP1307 isolated from a salt marsh

The compositions of long chain alkenes, alkenones and alkenoates in a cultured strain of the haptophyte Chrysotila lamellosa CCMP1307, isolated from a salt marsh, were investigated. The biomarker patterns were distinctive and showed a high proportion of tetraunsaturated alkenones and alkenoates, with a pronounced proportion of C-40 alkenones and a lack of C-38 methyl and C-39 ethyl alkenones. Linear regression of the alkenone unsaturation degree (UK37K) with growth temperature (T) was obtained over the range of possible CCMP1307 growth temperature values (4-20 degrees C): UK37K = 0.045 x T (degrees C) - 1.016, (n = 13, r(2) 0.96), while the UK37K ' values were weakly correlated with T: UK37K ' = 0.0035T (degrees C) + 0.0511 (n = 18, r(2) 0.70). The UK37K calibration exhibited a low y-intercept in comparison with that of a Chinese inland lake strain reported previously. The data show significant intraspecific variation in UK37K for C. lamellosa between strains from different geographic origins. C. lamellosa CCMP1307 reproduced typical UK37K values observed in C-37:4 rich lakes, especially at lower temperature (< 15 degrees C). In addition, we identified C-29:2, C-31:1, C-31:2 and C-31:3 alkenes, and found that the unsaturation degree of C-31 alkenes (U-31(en)), calculated with C-31: 1 and C-31:2 alkenes, might also be a useful index of growth temperature for the haptophyte C. lamellosa. (C) 2013 Elsevier Ltd. All rights reserved.