ABSTRACT
The leaves of a plant endemic to tropical Southeast Asia, Mitragyna speciosa Korth. (Rubiaceae), are traditionally used as a substitute for opium in Thailand and Malaysia. The leaves are known as “kratom,” “biak-biak,” or “ketum” in these countries, and they contain several alkaloids that vary in composition (e.g., between geographic variants) (Shellard et al. 1978; Takayama 2004; Kitajima et al. 2006). M. speciosa leaves from adult plants in Thailand have been reported to contain as the main alkaloid over 60% mitragynine (MG), whereas the corresponding content from the leaves in Malaysia is only approximately 10%. Paynantheine (PAY) and the MG diastereomer speciogynine (SG) were reported as the second most abundant alkaloids, and the MG diastereomer speciociliatine (SC) was the third abundant alkaloid in both plants (Takayama 2004). Shellard et al. (1978) described the distribution and probable biogenetic route of M. speciosa in young and mature leaves from Thailand. The alkaloidal pattern is different in the young plants from that in the older trees. The leaves of young Thai plants contain, in addition to MG, PAY, SG, and SC, the MG diastereomer mitraciliatine (MC) and the PAY diastereomer isopaynantheine (ISO-PAY)
11.1 Introduction .................................................................................153 11.2 Abused Substances of Kratom ....................................................155 11.3 Detection of MG and Its Analogs ...............................................156
