Pierre Eugène Marcellin Berthelot FRS FRSE (French: [bɛʁtəlo ]; 1827–1907) was a French chemist and politician noted for the Thomsen–Berthelot principle of thermochemistry. He synthesized many organic compounds from inorganic substances, providing a large amount of counter-evidence to the theory of Jöns Jakob Berzelius that organic compounds required organisms in their synthesis. Berthelot was convinced that chemical synthesis would revolutionize the food industry by the year 2000, and that synthesized foods would replace farms and pastures. "Why not", he asked, "if it proved cheaper and better to make the same materials than to grow them?"

Marcellin may refer to:

Marcellin is a given name. Notable people with the name include:

Marcellin Gaha Djiadeu (born March 24, 1982 in Bafang) is a professional Cameroonian footballer currently playing as player-coach for Unisport de Bafang.

Marcellin College may refer to:

The Philip Marcellin Grounds are a soccer venue in St. Lucia.