Paraffinic hydrocarbons in heterotrophic, photomixotrophic and photoautotrophic cell suspensions of Euphorbia characias L.

Abstract

We investigated the paraffinic hydrocarbon composition of cell suspensions of Euphorbia characias L. grown in different regimes of carbon and energy supply. Heterotropic (H), photomixotrophic (PM) and photoautotrophic (PA) cell suspensions were compared to leaves. Alkane compositions varied greatly both quantitatively and qualitatively according to the mode of culture. PM and H cells had indentical gaussian-like hydrocarbon distributions, with maxima around C 27 or C 28 compounds, while PA cells and leaf hydrocarbons were enriched in odd carbon chain-length compounds, especially C 29, C 31 and C 33 In long-term cultivated suspensions, total hydrocarbon amounts of PM and PA cells were about 5% and 6% that of leaf, respectively, and PA suspensions presented a major enrichment of all odd carbon chain-length compounds. Minor differences were observed between the growth phases of PM as well as PA cells. On the other hand, major differences appeared between these two modes of culture and were amplified along subcultures, indicating that the paraffinic hydrocarbon composition was directly related to the mode of culture. We discuss the possible origins of these alkane patterns.