[Systematic analysis of oral hypoglycemic agents in health foods].

A systematic analysis for 11 ingredients of oral hypoglycemic agent in health foods was established using three different analytical methods; i.e. thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC) and comparison of MS/MS spectra analyzed by liquid chromatography/tandem mass spectrometry (LC/MS/MS).

[Rapid determination of medical components found in the health food for weight loss by liquid chromatography/tandem mass spectrometry (LC/MS/MS)].

A method for the rapid determination of 11 medical components found in health foods for weight loss using liquid chromatography/tandem mass spectrometry (LC/MS/MS) has been developed. HPLC separation is performed on an ODS column with the gradient elution method. The mobile phase consists of two solvents.

Rapid quantification methods for genetically modified maize contents using genomic DNAs pretreated by sonication and restriction endonuclease digestion for a capillary-type real-time PCR system with a plasmid reference standard.

For rough quantitative analysis of genetically modified maize contents, rapid methods for measurement of the copy numbers of the cauliflower mosaic virus 35S promoter region (P35S) and MON810 construct-specific gene (MON810) using a combination of a capillary-type real-time PCR system with a plasmid DNA were established. To reduce the characteristic differences between the plasmid DNA and genomic DNA, we showed that pretreatment of the extracted genomic DNA by a combination of sonication and restriction endonuclease digestion before measurement is effective. The accuracy and reproducibility of this method for MON810 content (%) at a level of 5.

Quantification of genetically modified soybeans using a combination of a capillary-type real-time PCR system and a plasmid reference standard.

Because the labeling of grains and feed- and foodstuffs is mandatory if the genetically modified organism (GMO) content exceeds a certain level of approved genetically modified varieties in many countries, there is a need for a rapid and useful method of GMO quantification in food samples. In this study, a rapid detection system was developed for Roundup Ready Soybean (RRS) quantification using a combination of a capillary-type real-time PCR system, a LightCycler real-time PCR system, and plasmid DNA as the reference standard. In addition, we showed for the first time that the plasmid and genomic DNA should be similar in the established detection system because the PCR efficiencies of using plasmid DNA and using genomic DNA were not significantly different.