Gas-liquid chromatography of plant glycosides

Medicinal Plant Analysis: A Historical and Regional Discussion of Emergent Complex Techniques

The analysis of medicinal plants has had a long history, and especially with regard to assessing a plant's quality. The first techniques were organoleptic using the physical senses of taste, smell, and appearance. Then gradually these led on to more advanced instrumental techniques. Though different countries have their own traditional medicines China currently leads the way in terms of the number of publications focused on medicinal plant analysis and number of inclusions in their Pharmacopoeia. The monographs contained within these publications give directions on the type of analysis that should be performed, and for manufacturers, this typically means that they need access to more and more advanced instrumentation. We have seen developments in many areas of analytical analysis and particularly the development of chromatographic and spectroscopic methods and the hyphenation of these techniques. The ability to process data using multivariate analysis software has opened the door to metabolomics giving us greater capacity to understand the many variations of chemical compounds occurring within medicinal plants, allowing us to have greater certainty of not only the quality of the plants and medicines but also of their suitability for clinical research. Refinements in technology have resulted in the ability to analyze and categorize plants effectively and be able to detect contaminants and adulterants occurring at very low levels. However, advances in technology cannot provide us with all the answers we need in order to deliver high-quality herbal medicines and the more traditional techniques of assessing quality remain as important today.

Pharmacology of amygdalin (laetrile) in cancer patients

Plasma and urine concentrations of amygdalin, whole-blood concentrations of cyanide, and thiocyanate concentrations in serum and urine were determined in cancer patients following intravenous (4.5 g/m2) and oral (500-mg tablet) administration of amygdalin. To measure low plasma concentrations of amygdalin following oral administration a GC/MS assay was developed. Following intravenous administration, concentrations of parent drug as high as 1,401 microgram/ml were observed, with no increase in plasma concentrations of cyanide or serum concentrations of thiocyanate. Plasma elimination of amygdalin was best described by a two-compartment open model with a mean distributive phase half-life of 6.2 min, mean elimination phase half-life of 120.3 min, and mean clearance of 99.3 ml/min. Following oral administration of amygdalin, plasma concentrations were much lower, with peak values of less than 525 ng/ml. Cyanide concentrations increased to values as high as 2.1 microgram/ml whole blood. Thiocyanate concentrations did not increase for several days, plateauing at values as high as 38 microgram/ml serum. Ingestion of almonds by two patients taking oral amygdalin increased cyanide concentrations compared with values obtained after oral amygdalin alone.

Studies on monoterpene glucosides and related natural products. XXXI. Gas chromatography and gas chromatography-mass spectrometry of iridoid and secoiridoid glucosides

A total of 33 iridoid and secoiridoid glucosides were detected by gas chromatography on several columns such as OV-1 or OV-17. Representative glucosides were then subjected to gas chromatography-mass spectrometry, giving some characteristic peaks that permitted the discrimination of both types of glucosides from other compounds in most instances. The successful detection of both types of glucosides in several plant extracts showed the applicability of this combination of methods to small amounts of plant materials.