Historical terminology: who first coined the word “enzyme,” establishing a term that distinguishes soluble biocatalysts from living cells?

Introduction / Context:
The history of enzymology clarifies how scientists conceptualized catalysis. The term “enzyme” helped separate the idea of catalytic agents from whole organisms, paving the way for modern biochemistry and industrial biotechnology.

Given Data / Assumptions:

• The question asks who coined the word “enzyme.”
• Key historical figures include Wilhelm Kühne, Louis Pasteur, Justus von Liebig, and Eduard Buchner.

Concept / Approach:
In 1878, Wilhelm Kühne introduced the term “enzyme” (from Greek “in leaven”) to denote soluble ferments distinct from living yeast cells. Pasteur studied fermentation and posited “vitalism,” Liebig proposed chemical theories of fermentation, and Buchner later demonstrated cell-free fermentation (Nobel Prize 1907), but Kühne coined the term itself.

Step-by-Step Solution:

Verification / Alternative check:
Historical timelines in biochemistry texts consistently attribute the term “enzyme” to Kühne (1878).

Why Other Options Are Wrong:

• Pasteur: studied fermentation biology; did not coin the term.
• Liebig: advanced chemical theories; did not coin “enzyme.”
• Buchner: proved cell-free fermentation; did not coin the term.

Common Pitfalls:
Attributing the term to Buchner due to his landmark experiment; the terminology predates his work.

Final Answer:
Kuhne