Water-soluble substrates
also have been used. These are cheaper and are preferred
over hydrocarbons as substrates. Moreover, hydrocarbon substrates
are unacceptable for many applications such as in food, cosmetics,
and pharmaceutical industries. Non hydrocarbon
substrates include fats, oils, glycerol, or carbohydrates. Carbohydrates
and vegetable oils are among the most widely used substrates
for research on biosurfactant production