Léon-Gervais-Marie Maquenne (2 December 1853 – 10 January 1925) was a French

chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a graduated scientist trained in the study of chemistry, or an officially enrolled student in the field. Chemists study the composition of ...

and

plant physiologist Plant physiology is a subdiscipline of botany concerned with the functioning, or physiology, of plants. Plant physiologists study fundamental processes of plants, such as photosynthesis, respiration, plant nutrition, plant hormone functions, tropi ...

born in

Paris Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, largest city of France. With an estimated population of 2,048,472 residents in January 2025 in an area of more than , Paris is the List of ci ...

. From 1871 he worked in the laboratory of agricultural chemistry at the ''Ecole d'agriculture'' in Grignon. Here, he was a student of Pierre Paul Dehérain (1830-1902). In 1883 he became ''préparateur'' at the

Muséum national d'histoire naturelle The French National Museum of Natural History ( ; abbr. MNHN) is the national natural history museum of France and a of higher education part of Sorbonne University. The main museum, with four galleries, is located in Paris, France, within the Ja ...

, where from 1885 to 1898 he served as an assistant to the chair of ''Physiologie végétale''. In 1898 he succeeded

Georges Ville Georges Ville (23 March 1824 – 22 February 1897) was a French agronomist and plant physiologist born in Pont-Saint-Esprit. In 1843 he started his career as an interne in pharmacy. From 1857 to 1897 he held the chair of ''Physique végétale'' a ...

(1824-1897) as chair of ''Physique végétale'', a position he held on to until 1925. In 1904 he became a member of the

Académie des sciences The French Academy of Sciences (, ) is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French Scientific method, scientific research. It was at the forefron ...

. Among Maquenne's contributions was research involving the chemical make-up of

sugar alcohols Sugar alcohols (also called polyhydric alcohols, polyalcohols, alditols or glycitols) are organic compounds, typically derived from sugars, containing one hydroxyl group attached to each carbon atom. They are white, water-soluble solids that ca ...

. He was able to resolve the chemical constitution of

inositol In biochemistry, medicine, and related sciences, inositol generally refers to ''myo''-inositol (formerly ''meso''-inositol), the most important stereoisomer of the chemical compound cyclohexane-1,2,3,4,5,6-hexol. Its elemental formula, formula is ...

and demonstrated it to be a hexahydroxycyclohexane. He is credited with invention of the so-called "Maquenne block", an apparatus used for determining the

melting point The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state of matter, state from solid to liquid. At the melting point the solid and liquid phase (matter), phase exist in Thermodynamic equilib ...

of chemical compounds.
Archive.org, "A handbook of sugar analysis"

Written works

* ''Les Sucres et principaux dérivés'' (1900, 1032 pages) – The

sugars Sugar is the generic name for Sweetness, sweet-tasting, soluble carbohydrates, many of which are used in food. Simple sugars, also called monosaccharides, include glucose, fructose, and galactose. Compound sugars, also called disaccharides ...

and their major derivatives. * ''Précis de Physiologie végétale'' (1921) – Handbook of Plant Physiology.

References

Biographies des principaux personnages du Muséum
(Biography in French) {{DEFAULTSORT:Maquenne, Leon 19th-century French chemists Scientists from Paris 1925 deaths 1853 births Plant physiologists Burials at Père Lachaise Cemetery 20th-century French chemists