Evaluation of an ethnopharmacologically selected Bhutanese medicinal plants for their major classes of Phytochemicals and biological activities

A new protoberberine alkaloid from Meconopsis simplicifolia (D. Don) Walpers with potent antimalarial activity against a multidrug resistant Plasmodium falciparum strain

“…Since the crude extracts of a Bhutanese antimalarial medicinal plant, M. simplicifolia has exhibited significant antiplasmodial activity (Wangchuk et al, 2011), we examined compounds 1 and 3-5 for their antiplasmodial and cytotoxic activities ( Table 2). Because of solubility problems, the IC 50 values could not be accurately determined for compounds 3-5…”

“…Its aerial parts (stems, leaves, flowers and fruit), in combination with other ingredients, are used for preparing more than eight important BTM multi-ingredient formulations. As an individual plant, it is indicated for treating coughs and colds, fever and infections in the liver, lung and blood which show correlations to the symptoms of cancer, microbial infections and malaria (Wangchuk et al, 2008(Wangchuk et al, , 2011. Malaria causes 2-3 million deaths each year (Marti et al, 2010).…”

“…History tells us that the plant-based drugs including traditional medicinal plants and compounds derived from them are the important sources of antimalarial drugs. The BTM, which depends upon the country's rich biodiversity, may offer alternative treatment regimens by promising a source of antimalarial extracts and new drug lead compounds as revealed by previous studies on Bhutanese medicinal plants (Wangchuk et al, 2008(Wangchuk et al, , 2010(Wangchuk et al, , 2011(Wangchuk et al, , 2012a(Wangchuk et al, , 2012b Plasmodium falciparum with IC 50 values of 6.39 µg/ml and 0.40 µg/ml, respectively (Wangchuk et al, 2011). Based on this earlier finding we have further investigated this plant for its phytochemicals and their biological activities and consequently discovered a new protoberberine type alkaloid along with five known protopine and benzophenanthridine type alkaloids (1-6) ( Fig.…”

Antimalarial polyoxygenated and prenylated xanthones from the leaves and branches of Garcinia mckeaniana

“…20 Table 2 NMR spectroscopic data (400 MHz in acetone-d 6 ) of mckeanianones D (4) 4 Hz, H-3, H-5)] which were assigned to the aromatic protons of rings B and E, respectively, four uncoupled (singlet) aromatic protons ( H 6.63, 6.57, 6.33 and 6.33, each 1H, H-3, H-8, H-6 and H-6, respectively) and one methoxy group ( H 3.82). The 13 C NMR and DEPT 135 spectra of 6 displayed only twenty-seven resonances for the total of thirty-one carbons; eighteen quaternary carbons ( C 183.3, 182.1, 165.2, 165.1, 164.7, 163.6, 163.5, 163.1, 163.0, 160.8, 158.9, 156.4, 124.8, 124.2, 111.2, 105.6, 104.7 All of the isolated compounds were tested for their antimalarial activities against the Plasmodium falciparum strains, TM4 and K1 (a multidrug resistant strain) 23 and their cytotoxic activity against a Vero cell line (African green monkey kidney cells) 24 (Table 4). …”

An assessment of the Bhutanese traditional medicine for its ethnopharmacology, ethnobotany and ethnoquality: Textual understanding and the current practices

“…Therefore, with the aim of generating good scientific data to assist this cause, we have recently engaged in studies of selected medicinal plants used in BTM. The findings in terms of ethnobotanical identification, phytochemical content and biological activity studies were previously reported (Wangchuk et al, 2007b(Wangchuk et al, , 2010a(Wangchuk et al, , 2010b(Wangchuk et al, , 2011a(Wangchuk et al, , 2011b(Wangchuk et al, , 2012a(Wangchuk et al, , 2012b.These studies required us to first gain an intimate understanding of the BTM, its materia medica, pharmacopoeia, concepts, ethnoquality, medicinal plants and its current practices in Bhutan. Therefore, we studied the BTM methods, traditional literature, current BTM practices, BTM practitioners' views and analyzed them with a modern scientific perspective.…”