Table 2.

GC-MS Profiles of GA Metabolites by Recombinant EUIa

SampleRetention Time on GC in min (KRI)Characteristic Ions, m/z (Relative Intensity)
GA4 metaboliteb9.07 (2709)434 [M+] (5), 305 (15), 249 (32), 245 (23), 241 (37), 217 (22), 183 (23), 129 (42), 73 (100)
Authentic 16α,17-epoxy GA4b9.05 (2707)434 [M+] (6), 305 (15), 249 (34), 245 (25), 241 (42), 217 (24), 183 (26), 129 (46), 73 (100)
Authentic 16β,17-epoxy GA4b9.00 (2700)434 [M+] (5), 305 (16), 249 (28), 245 (23), 241 (40), 217 (20), 183 (21), 129 (38), 73 (100)
GA9 metabolitec7.97 (2524)346 [M+] (2), 286 (8), 270 (8), 242 (100), 225 (19), 185 (37), 183 (32), 159 (21), 129 (20)
Authentic 16α,17-epoxy GA9c7.97 (2524)346 [M+] (2), 286 (7), 270 (7), 242 (100), 225 (18), 185 (37), 183 (32), 159 (18), 129 (18)
Authentic 16β,17-epoxy GA9c7.90 (2512)346 [M+] (2), 286 (8), 270 (6), 242 (100), 225 (20), 185 (38), 183 (39), 159 (20), 129 (20)
GA12 metabolitec8.22 (2556)376 [M+] (1), 344 (100), 316 (38), 301 (38), 285 (29), 257 (77), 241 (43), 227 (40), 199 (63)
Authentic 16α,17-epoxy GA12c8.22 (2556)376 [M+] (2), 344 (100), 316 (38), 301 (36), 285 (25), 257 (76), 241 (35), 227 (40), 199 (59)
  • a Metabolites were purified in the absence of acetic acid.

  • b Methyl ester-TMSi ether derivative.

  • c Methyl ester derivative. M+, molecular ion.