THE CONTENT OF TOTAL ASH, ACID-INSOLUBLE ASH AND PESTICIDE RESIDUE DETECTION CONTAINED OF ZINGIBERACEAE CRUDE DRUGS IN BANGKOK

Abstract

In this study, the total ash content, acid-insoluble ash content, and pesticide residues were
examined in 10 species of the Zingiberaceae family, namely Zingiber zerumbet (L.) Roscoe ex Sm.,
Kaempferia parviflora Wall. ex Baker., Boesenbergia rotunda (L.) Mansf., Curcuma longa L., Curcuma zedoaria (Christm.) Roscoe., Alpinia galanga (L.) Willd., Zingiber officinale Roscoe., Kaempferia galanga L., Zingiber montanum (J.Koenig) Link ex A.Dietr. and Curcuma comosa Roxb. All crude drugs were purchased from three herbal drugstores in Bangkok. The total ash and acid- insoluble ash contents were determined according to the Thai Herbal Pharmacopoeia. The detection of pesticide residue contamination using the GPO-TM Kit, that for detection of all four pesticide groups. The results showed that the total ash and acid-insoluble ash contents of Z. zerumbet, K. galangal, Z. montanum and C. comosa were under the official standard value that has passed the Thai Herbal Pharmacopeia standard criteria. Pesticide residues from organophosphate and carbamate pesticides were detected in all 10 dried species of the Zingiberaceae family. Nonetheless, pyrethroid and organochlorine pesticides had not been detected. Pesticide residue detection with test kits serves as a preliminary screening. Therefore, the rhizomes should be thoroughly cleansed according to the five principles of Thai traditional pharmaceutical ethics in order to reduce the amount of pesticide residues before being used to prepare drugs that may affect human health.