DEVELOPMENT OF A QUALITY CONTROL PROTOCOL FOR PELARGONIUM SIDOIDES USING NEAR INFRARED SPECTROSCOPY (NIRS)

Abstract

Quality control analysis is vital in the pharmaceutical industry to guarantee the authenticity and the quality of products. A major challenge in quality assurance of herbal material is the vast variation of active constituents in plants from the same species. As a result of this variation, the selection of only a few compounds as criteria for quality control is inadequate. Identification is one of the first steps in quality and safety assurance of herbal medicinal products. Identification tests should be able to discriminate between related species and/or potential adulterants. Pelargonium sidoides is indigenous to South Africa with a centre of diversity in the Eastern Cape Province. It is highly valued in South Africa by traditional healers. For hundreds of years various ethnic groups have used root extracts of P. sidoides as a remedy for coughs, upper respiratory tract irritations and gastrointestinal conditions. An ethanol extract of P. sidoides is used in the proprietary herbal tincture known as Umckaloabo® that is currently being successfully marketed in Germany with sales that have escalated over 700%. For many years the true taxonomic identity of this herbal medicine was debated. In 1974 the origin of the decoction was claimed to be P. reniforme. It is now speculated that identification was wrong and that P. sidoides was used. Despite the commercial interest in P. sidoides very few studies have been conducted to document the full phytochemical range of the variation for natural populations and to construct a fast accurate quality assurance method for the validation of raw material. High performance liquid chromatography (HPLC) and thin layer chromatography (TLC) are being used for the validation of P. sidoides raw material. In this project near infrared profiles of P. sidoides and P. reniforme were constructed and compared. Plant samples were collected from different locations in the Eastern Cape Province of South Africa. The NIRS data were used to do qualitative analysis in orderto detect the relationships among all samples. Quantitative analysis was done to construct a calibration curve that can accurately predict the percentage of contamination of P. sidoides with P. reniforme.