Submitted to: Mutation Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/24/1999
Publication Date: N/A
Interpretive Summary: It is well known that certain plants have health benefits that exceed nutritional needs. However, new methodology is needed to effectively identify, quantitate, and evaluate the activity of chemicals from plants which may have long-term effects on chronic diseases in humans. A processed soybean extract, prepared from material left over after the oils and proteins have been removed, was shown to prevent damage by a potent carcinogen to mammalian cell DNA. A series of compounds were isolated and identified from this material and their chemoprotective activity confirmed in model assay systems using mammalian cell cultures. This is an early step in sorting out which of these plant chemicals should be selected for further study in animal models and long-term human nutritional studies using diet to prevent cancers. This work will be of interest primarily to other scientists and soy processors.
Technical Abstract: An extract was prepared from a commercial soybean processing by- product (soybean molasses) and was fractionated into purified chemical components. In previous work, this extract (PCC) repressed induced genomic DNA damage, whole cell clastogenicity, and point mutation in cultured mammalian cells. In the current study, a chemical fraction was isolated from PCC using preparative high-performance liquid chromatography. This fraction, PCC100, repressed 2-acetoxyacetylaminofluorene (2AAAF)-induced DNA damage in Chinese hamster ovary cells as measured by single cell gel electrophoresis (alkaline Comet assay). Using liquid chromatography-electrospray ionization-mass spectroscopy and 1H and 13C nuclear magnetic resonance spectroscopy, PCC100 was shown to consist of a mixture of group B soyasaponins and 2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran- 4-one (DDMV) soyasaponins. These included soyasaponins I, II, III, IV, V, Be, beta-g, beta-a, gamma-g and gamma-a. Purified soyasapogenol B aglycone prepared from fraction PCC100 demonstrated significant antigenotoxic activity against 2AAAF. To our knowledge, these data demonstrate for the first time the antimutagenic activity of soybean saponins in mammalian cells.