| Popis: |
A survey of known anatoxin solvent systems for resolution of aflatoxins M1 and M2 on TLC plates revealed that the best system for determining aflatoxins B1, B2, G1, G2, M1, and M2 is isopropyl alcohol-acetone-chloroform (5 + 10 + 85). Substitution of various alcohols for isopropyl alcohol in this system demonstrated that maximum resolution of M1 and M2 was achieved with n-amyl alcohol-acetone-chloroform (10 + 10 + 80); however, B1, B2, G1, and G2 migrated with the solvent front. When alcohol-chloroform (5 + 95) mixtures were investigated, n-propyl, n-butyl, and tert-butyl alcohol + chloroform resolved M1 and M2 best but did not separate B1, B2, G1, or G2. Molar absorptivities of both M1 and M2 were determined in methanol, chloroform, acetonitrile, and acetonitrile-benzene (2 + 98). Relative fluorescent intensities of aflatoxins B1, M1, and M2 were compared on both developed and undeveloped TLC plates. Fluorescent intensities of B1 and M1 on silica gel were nearly equal, and the intensity of M2 was 1.4–1.5 times that of the other 2 aflatoxins. Water adducts of anatoxin M1 and parasiticol were prepared. The diacetate adducts of parasiticol were formed by treatment with acetic anhydride and concentrated HC1. Monoacetyl derivatives of M1, M2, and parasiticol were obtained by treatment with pyridine and acetic anhydride. Good resolution of the water-addition derivatives of B1, G1, parasiticol, and Mi on TLC plates was achieved with isopropyl alcoholacetone-chloroform (5 + 10 + 85). |
