Variation in the deoxynucleotide composition between organic and nonorganic strawberries.

The differences in xenobiotic chemical content between organic and nonorganic products can be chemically measured. In this study, the deoxynucleotide composition of strawberry samples is used to demonstrate chromatographic methods of quantifying the differences between pesticide- and toxic-exposed strawberries. The samples were analyzed by (32)P labeling and two-dimensional thin-layer chromatography. This technique is sensitive for detecting rare (1/10(10)) deoxynucleotide adducts and analogues (minor bases) in DNA. The results indicate differences in the amount and type of adduct formation between organic and nonorganic strawberry samples and within different parts of the same type of sample. The elucidation of the content and effects of pesticides and toxics in foods is critical in differentiating organic from common produce. It can also aid the agricultural industry in improving the application of chemicals in pest management. Furthermore, it helps to enhance the understanding of long-term epidemiology in nutrition research, especially in susceptible populations. These findings are of particular application in the pediatric population, where dietary habits are restricted to specific food groups.

Interstrain variation in the deoxynucleotide composition of Cryptococcus neoformans: nucleotide composition of Cryptococcus neoformans.

The deoxynucleotide (dNMP) composition of ten strains of C. neoformans was analysed by 32P-labelling and two-dimensional thin-layer chromatography. This technique is very sensitive for detecting rare deoxynucleotide adducts and analogues (minor bases) in DNA. The results indicate considerable variation among strains in DNA nucleotide composition.