Herbaceous grasses that grow wild in several tropical and subtrop ical regions. The East Indian variety is grown in eastern India,
Cambodia, Singapore, and Ceylon. The West Indian type is grown
in Madagascar, the Comoro Islands, Guatemala, Honduras, Brazil,
Haiti, and Puerto Rico. The East Indian variety yields an alcohol
soluble oil (1:2 in 70% alcohol); West Indian lemongrass is soluble 1:10 in 90% alcohol with haze. The part used is the herbaceous
portion. Lemongrass has a strong, pungent, lemon-like odor.
The essential oil is obtained by steam distillation of freshly cut
(East Indian variety) or partially dried (West Indian variety) grass
in approximately 0.2 to 0.3% and 0.31 to 0.37% yields, respec tively.
East Indian Lemongrass Oil: East Indian lemongrass oil is a
pale-yellow to brown-yellowish liquid; it has a characteristic,
sharp, pungent, lemon-like odor because of the large amount of
citral present (80 to 85%).
In addition to citral, the main constituents of the East Indian oil
include citronellal, geraniol, nerol, famesol, dipentene, methylhep tenone, and probably limonene.
West Indian Lemongrass Oil: West Indian lemongrass oil is a
pale-yellow to brownish liquid with a pronounced citral odor. Its
physical-chemical constants are as follows.
Its main constituents include isovaleric aldehyde, furfural, myrcene,
dipentene, methylheptenone, aldehyde C10, citronellal, various esters,
linalool, geraniol, nerol, and terpenes.
Constituents include: andrographolide; andrographidin A; andro graphidin B; andrographidin C; andrographidin D; andrographidin
E; andrographidin F; andrographin; andrographinin; andrographi side; andropanoside; apigenin-4,7-di-o-methyl ether; gamma-bis abolene; caffeic acid; carvacrol; chlorogenic acid; deoxyandro graphiside; dicaffeoyl quinic acid; 5-dihydroxy-7,8-dimethoxy flavone; eugenol; 2-cis-6-trans-famesol; 2-trans-6-trans-farnesol;
5-hydroxy-7,8-dimethoxyflavone; 5-hydroxy-2,3,7,8-tetrameth oxyflavone; myristic acid; oroxyline A; panicolin; paniculide B;
and sitosterol-α-1.
