魏克斯曼(Waksman)氏在1942年对抗菌素作了如下的定义:“抗菌素是微生物在新陈代谢过程中所产生,具有抑制他种微生物生长或代谢的化学物质。”但以后陆续发现抑制癌的代谢和生长的物质,以及对特异性酶具有抑制作用的物质等,其定义也就扩大解释为“微生物产生的显示生物活性的物质”的 In 1942, Waksman made the following definition of an antibiotic: “An antibiotic is a chemical produced by a microorganism during its metabolism and has the ability to inhibit the growth or metabolism of other microorganisms.” However, one after another has discovered that inhibiting cancer The substance which is metabolized and grows, and the substance which has the inhibitory effect on a specific enzyme, the definition is also expanded and interpreted as “the substance which shows the bioactivity which a microorganism produces”