Comparison of intensely sweet volatile leaf oils of Lippia dulcis (Verbenaceae) with low and high camphor from Brazil and Mexico

Lippia dulcis is a sweet-tasting, woody herb but the sweetness is often mixed with a camphorous taste. Lippia dulcis oil from Brazil was found to be low in camphor (trace), whereas the oil from Mexico had considerable camphor (33.9%). The Lippia oil from Brazil was high in 6-methyl-5-hepten-2-one (10.5%), α-copaene (8.6%), (E)-caryophyllene (10.6%), bicyclogermacrene (6.6%), δ-cadinene (7.2%), epi-α-bisabolol (6.5%) and hernandulcin (8.8%). In addition, it contained β-cedrene and α-calacorene, compounds found in cedarwood oils. The Lippia oil from Mexico was high in camphene (12.7%), limonene (4.6%), camphor (33.9%), α-copaene (4.0%), (E)-caryophyllene (6.0%) and hernandulcin (5.9%). In addition, it contained alkanes and acids (docosane, tricosane, tetracosane, pentacosane, linoleic acid and octadecanoic acid) that were not found in the Lippia oil from Brazil. The Brazil germplasm with low-camphor and high hernandulcin is worthy of conservation, as it could be an important alternative source of sweeteners. Published on-line www.phytologia.org Phytologia 98(3): 207-214 (July 6, 2016). ISSN 030319430.