Chemical standaridization and cultivation of traditional Chinese medicine-orchid family

Abstract

Under this grant, works were carried out to extract and isolate bioactive compounds for chemical standardization of Traditional Chinese Medicine (TCM) orchids such as Gastrodia elata Blume (Orchidaceae)(GE). GE is a notable Chinese medicine and its roots have been widely used for the treatment of epilepsy, headache, rheumatism and vertigo. The major bioactive compounds are gastrodin (GA), vanilly alcohol (VA) and 4-hydroxybenzaldyde (HBA) (Figure 1). Quality, safety and efficacy of herbal medicines are important issues to be addressed toward evidence-based medicine. The analysis of botanicals and herbal preparations involves the combination of extraction methods and analytical techqniues such as separation tools. In the extraction of bioactive compounds from botanicals, laborious and high solvent consumption methods such as heating under reflux and Soxhlet are widely used. In the move to reduce or eliminate use of organic solvents and improve extraction processes, newer sample preparation methods such as pressurized liquid extraction (PLE) and pressurized hot water extraction (PHWE) have been introduced for extraction of bioactive compounds present in plant materials. The aim of the current work was to support the various objectives of RP/04/06TSN, to determine GA and VA present in GE plant materials using PLE at room temperature with aqueous mixture of ethanol. The instrumentation used was based on a low cost laboratory-assembled system (Figure 2). The extraction efficiency of the proposed method was compared with heating under reflux with aqueous mixture of alcohol.