difference between activators, inhibitors, promoters and co-enzymes.

Activators are metal ions like Na⁺, Mn²⁺, Co²⁺, Cu²⁺, etc. which get weakly bonded to enzyme molecule and therefore, promote their catalytic action.

Inhibitors are the chemicals that retard the activity of a catalyst. In other words, they have a negative effect on the activity of a catalyst. For example, the inhibitors interact with the active functional groups on the enzyme surface and often reduce or completely destroy the catalytic activity of the enzymes. The use of many drugs is related to their action as enzyme inhibitors in the body.

Promoters, on the other hand are substances that enhance the activity of a catalyst. For example in Haber's process, iron act as a catalyst. And molybdenum is added into it, which increases the efficiency of iron, hence acts as promoter.

Co-enzymes are a category of co-factors (non-protein part of the enzyme) that are loosely bound to the enzyme. The essential chemical components of many coenzymes are vitamins, e.g., coenzyme nicotinamide adenine dinucleotide (NAD) and NADP contain the vitamin niacin.