Structural characterization of monoterpene indole alkaloids in ethanolic extracts of Rauwolfia species by liquid chromatography with quadrupole time-of-flight mass spectrometry

Rauwolfia species(Apocynaceae) are medicinal plants well known worldwide due to its potent bioactive monoterpene indole alkaloids(MIAs) such as reserpine,ajmalicine,ajmaline,serpentine and yohimbine.Reserpine,ajmalicine and ajmaline are powerful antihypertensive,tranquilizing agents used in hypertension.Yohimbine is an aphrodisiac used in dietary supplements.As there is no report on the comparative and comprehensive phytochemical investigation of the roots of Rauwolfia species,we have developed an efficient and reliable liquid chromatography-tandem mass spectrometry(LC–MS/MS) method for ethanolic root extract of Rauwolfia species to elucidate the fragmentation pathways for dereplication of bioactive MIAs using highperformance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry(HPLC–ESI–QTOF–MS/MS) in positive ion mode.We identified and established diagnostic fragment ions and fragmentation pathways using reserpine,ajmalicine,ajmaline,serpentine and yohimbine.The MS/MS spectra of reserpine,ajmalicine,and ajmaline showed C-ring-cleavage whereas E-ring cleavage was observed in serpentine via Retro Diels Alder(RDA).A total of 47 bioactive MIAs were identified and characterized on the basis of their molecular formula,exact mass measurements and MS/MS analysis.Reserpine,ajmalicine,ajmaline,serpentine and yohimbine were unambiguously identified by comparison with their authentic standards and other 42 MIAs were tentatively identified and characterized from the roots of Rauwolfia hookeri,Rauwolfia micrantha,Rauwolfia serpentina,Rauwolfia verticillata,Rauwolfia tetraphylla and Rauwolfia vomitoria.Application of LC–MS followed by principal component analysis(PCA) has been successfully used to discriminate among six Rauwolfia species.

Ethnobotanical survey of medicinal plants used in the management of cancer and diabetes

OBJECTIVE:To conduct an ethnobotanical survey and document the traditional anticancer and antidiabetic plants used by the local tribes of Mizoram,Northeast India.METHODS:A systematic survey was conducted in rural and urban areas of Mizoram by interviewing traditional practitioners,and cancer and diabetes patients.A detailed literature search was carried out using MEDLINE and SCOPUS and available literatures were selected and included in the study.The use value(UV)of the selected plants was calculated based on the number of citations per species given by informants.RESULTS:Data was obtained for 201 traditional medicinal plants from Mizoram,Northeast India.These plants were from 72 different families and belonged to 140 genera.Of these,103 plants were reported for the first time as possessing either anticancer or antidiabetic potential,and 105 plants were identified that were used for the treatment of both diseases.Three plants(Phlogacanthus thysiformis,Solanum gilo and Lobelia angulata)with antidiabetic potential,and six plants(Dillenia scabrella,Circium sinesis,Eupatorium nodiflorum,Pratia begonifolia,Vernonia teres and Plantago erosa)with both as anticancer and antidiabetic potential were documented for the first time.CONCLUSION:In this study,we documented several explored and unexplored medicinal plants that may be useful for the management of cancer and diabetes.This study suggests that there is a broad scope fordeveloping potent anticancer and antidiabetic agent from the flora of Mizoram,Northeast India.