Enzymes are often more effective, need less energy and they function under milder conditions than chemicals. They also only interact with organic raw materials which are renewable resources. All this allows real advances in the environmental performance of production processes, through lower energy consumption, lower waste production, and biodegradability.
Enzymes are highly specific: they can be compared to a key to an individual lock, rather than to a chemical axe to break down the door. Processes which use enzymes generally have fewer side reactions and by-products than chemical ones, and are more environmentally friendlier.
Enzymes also allow some processes to be carried out, which would otherwise not be practical.
Because of its three-dimensional structure, the activity of an enzyme is easily destroyed. This makes enzymes even more attractive as in most cases they can be easily and readily inactivated after use.