The tomato saponin, esculeoside A.
Esculeoside A (2), a spirosolane steroidal glycoside, is a major constituent isolated from Solanum lycopersicum, a commercial strain of mini tomatoes. The content variability of esculeoside A (2) was examined in mini, midi, and Momotaro tomatoes and various processed tomato products. In the green immature tomato fruit, tomatine (1) is oxidized at C-23 and C-27 to produce esculeoside A (2) in the ripe fruit. Further, esculeoside A (2) is partly converted to 3β-hydroxy-5α-pregn-16-en-20-one 3-O-β-lycotetraoside (6), a pregnane glycoside, in the overripe fruit. Esculeogenin A (3), the sapogenol of 2, is easily converted into 3β,16β-dihydroxy-5α-pregn-20-one (17). Metabolic studies showed excretion of androstane derivatives in the urine of human volunteer subjects after tomato consumption. Esculeogenin A (3) inhibited the accumulation of cholesterol esters in macrophages through its effects on acyl-CoA:cholesterol acyl transferase (ACAT). Oral administration of esculeoside A (2) to apoE-deficient mice significantly reduced serum levels of cholesterol, triglycerides, and LDL-cholesterol and ameliorated the severity of atherosclerotic lesions.
Nohara
Toshihiro
T
Faculty of Pharmaceutical Sciences, Sojo University, 22-1, 4-Chome, Ikeda, Kumamoto 860-0082, Japan. none@ph.sojo-u.ac.jp
Ono
Masateru
M
Ikeda
Tsuyoshi
T
Fujiwara
Yukio
Y
El-Aasr
Mona
M
D000818:Animals; D006801:Humans; D018551:Solanum lycopersicum / Q000737:chemistry* / Q000235:genetics; D051379:Mice; D015394:Molecular Structure; D012502:Sapogenins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D012503:Saponins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
D012502:Sapogenins; D012503:Saponins; C530544:esculeoside A