Research articleBiochemical precursor effects on the fatty acid production in cell suspension cultures of Theobroma cacao L.

- The effect of precursors feeding over the fatty acids production in cacao cells suspension was evaluated.
- Biotin proved to be an adequate precursor to enhance fatty acid synthesis without altering cell viability and growing.
- An easy and economical protocol of fatty acids subcellular localization using enzymatic markers was standardized.
- We hypothesize that pentose phosphate pathway is the prevailing mechanism for the fatty acid precursors in cacao cells.

Cocoa butter (CB) is composed of 96% palmitic, stearic, oleic, linoleic and linolenic fatty acids that are responsible for the hardness, texture and fusion properties of chocolate. Through in vitro plant cell culture it is possible to modify CB lipid profiles and to study the fatty acid biosynthesis pathway on a subcellular level, evaluating fundamental aspects to enhance in vitro fatty acid production in a specific and controlled way. In this research, culture media was supplemented with acetate, biotin, pyruvate, bicarbonate and glycerol at three different concentrations and the effects on the biomass production (g/L), cell viability, and fatty acids profile and production was evaluated in in vitro cell suspensions culture. It was found that biotin stimulated fatty acid synthesis without altering cell viability and cell growth. It was also evident a change in the lipid profile of cell suspensions, increasing middle and long chain fatty acids proportion, which are unusual to those reported in seeds; thus implying that it is possible to modify lipid profiles according to the treatment used. According to the results of sucrose gradients and enzyme assays performed, it is proposed that cacao cells probably use the pentose phosphate pathway, mitochondria being the key organelle in the carbon flux for the synthesis of reductant power and fatty acid precursors.