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Pettenkofer, Max von

(Encyclopedia)Pettenkofer, Max von mäks fən pĕtˈənkōˌfər [key], 1818–1901, German chemist and hygienist. He studied medicine at Munich. Pettenkofer is considered a founder of epidemiology and is known for...

bile

(Encyclopedia)bile, bitter alkaline fluid of a yellow, brown, or green color, secreted, in man, by the liver. Bile, or gall, is composed of water, bile acids and their salts, bile pigments, cholesterol, fatty acids...

threonine

(Encyclopedia)CE5 threonine thrēˈənēn [key], organic compound, one of the 22 α-amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essen...

Grassmann, Hermann Günther

(Encyclopedia)Grassmann, Hermann Günther hĕrˈmän günˈtər gräsˈmän [key], 1809–77, German mathematician and Sanskrit scholar, educated in Berlin. He invented a new algebra of vectors (somewhat similar to...

fusel oil

(Encyclopedia)fusel oil fyo͞oˈzəl [key], oily, colorless liquid with a disagreeable odor and taste. It is a mixture of alcohols (largely amyl alcohols) and fatty acids, formed during the alcoholic fermentation o...

Mitscherlich, Eilhard

(Encyclopedia)Mitscherlich, Eilhard īlˈhärt mĭchˈərlĭkh [key], 1794–1863, German chemist. He was professor at Berlin from 1822. Noted for his discovery of the principle of isomorphism, he did important wor...

Willstätter, Richard

(Encyclopedia)Willstätter, Richard rĭkhˈärt vĭlˈshtĕtər [key], 1872–1942, German chemist. He was professor at the Kaiser Wilhelm Institute of Chemistry, Berlin (1912–16), and at the Univ. of Munich (191...

methionine

(Encyclopedia)CE5 methionine mĕthīˈənēn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the L-stereoisomer appears in mammalian protein. It is one of the several e...

leucine

(Encyclopedia)CE5 leucine lo͞oˈsēn [key], organic compund, one of the 20 amino acids commonly found in animal proteins. Only the l-stereooisomer appears in mammalian protein. It is one of several essential am...

boric acid

(Encyclopedia)boric acid, any one of the three chemical compounds, orthoboric (or boracic) acid, metaboric acid, and tetraboric (or pyroboric) acid; the term often refers simply to orthoboric acid. The acids may be...