Isolation, characterization, and surfactant properties of the major triterpenoid glycosides from unripe tomato fruits.
Various triterpenoid glycosides were extracted from whole unripe tomato fruits ( Lycopersicon esculentum cv. Cedrico), using aqueous 70% (v/v) ethanol to study their surfactant properties. Cation-exchange chromatography using a Source 15S column and subsequent semipreparative HPLC using an XTerra RP18 were employed to purify individual triterpenoid glycosides from the extract. The structure of the purified compounds was established by mass spectrometry and nuclear magnetic resonance spectroscopy. The furostanol glycoside tomatoside A (749 mg/kg of DW) and the glycoalkaloids alpha-tomatine (196 mg/kg of DW) and esculeoside A (427 mg/kg of DW) were the major triterpenoid glycosides present. Furthermore, minor amounts of a new dehydrofurostanol glycoside, dehydrotomatoside, were found. The critical micelle concentrations of the major triterpenoid glycosides, alpha-tomatine, tomatoside A, and esculeoside A, were determined as 0.099, 0.144, and 0.412 g/L, respectively. The results show that tomatoside A, and not the more well-known alpha-tomatine, is the predominant triterpenoidal surfactant in unripe tomato fruits.
Yamanaka
Takao
T
Wageningen University, The Netherlands.
Vincken
Jean-Paul
JP
de Waard
Pieter
P
Sanders
Mark
M
Takada
Norihisa
N
Gruppen
Harry
H
D005638:Fruit / Q000737:chemistry*; D006027:Glycosides / Q000737:chemistry* / Q000302:isolation & purification*; D018551:Solanum lycopersicum / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification; D013501:Surface-Active Agents / Q000737:chemistry* / Q000302:isolation & purification*
D006027:Glycosides; D010936:Plant Extracts; D013501:Surface-Active Agents