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The kinetics of glycolipids production has considerable variations among various systems. Only a few generalizations can be made, by grouping kinetic parameters into the following types: (1) growth-associated production, (2) production under growth-limiting conditions, (3) production by resting or immobilized cells, and (4) production with precursor supplementation (Desai and Banat 1997; Santos et al. 2016).

Examples for the growth-associated production (1) can be the synthesis of rhamnolipids by some Pseudomonas spp strains. The biosurfactant production is in direct relation to growth and substrate utilization. The excreted emulsan-like substance accumulates on the cell surface during the exponential phase of growth (Desai and Banat 1997).

The production under growth-limiting conditions (2) is characterized by an accentuated increase in the biosurfactant level as a result of the limitation of one or more medium components. An example is the production of rhamnolipids by Pseudomonas aeruginosa, particularly when the cells become limited for nitrogen or iron. The limitation results in an overproduction of biosurfactant when the culture reaches the stationary phase of growth (Desai and Banat 1997; Kumari et al. 2010).

Production by resting or immobilized cells (3), describes a biosurfactant production with no cell multiplication; whereby the cells nevertheless continue to utilize the carbon source for biosurfactant synthesis. For example the gram-positive bacterium Arthobacter crystallopoietes was shown to directly produce trehalose from maltose by resting cell reaction (Desai and Banat 1997; Seo and Shin 2011).

Santos et al. (2016) report that the addition of biosurfactant precursors (4) to the growth medium can cause qualitative and quantitative changes in the final product (Ashby et al. 2008; Santos et al. 2016).

Furthermore different factors, such as the carbon source, nitrogen source or environmental conditions can influence the glycolipids production and will be focus on next points in the case study of trehalose lipids.