who discovered the above mentioned which catalyze the chemical reaction?
Anselme Payen was the first to discover an enzyme ,diastase.
Enzyme

French chemist Anselme Payen was the first to discover an enzyme, diastase, in 1833
a food preservation method in which microorganisms metabolize components of a food is UNANSWERABLE what do you mean by metabolism? It is the set of life-sustaining chemical reactions in organisms. what are the main purposes of it? The conversion of food/fuel to building blocks for proteins, lipids, nucleic acids, and some carbohydrates; and the elimination of metabolic wastes. what is the role of amino acids and protein in this process? Proteins are made of amino acids arranged in a linear chain joined together by peptide bonds. Many proteins are enzymes that catalyze the chemical reactions in metabolism.
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Enzyme [SEP] Etymology and history
The word "enzyme" was used later to refer to nonliving substances such as pepsin, and the word "ferment" was used to refer to chemical activity produced by living organisms.