Analysis Alkaloids 43 Medicinal plants 41 Therapeutic use 36 Synthesis 30 Heavy metals 24 Water 23 Cancer 22 Environmental aspects 22 Trace elements 21 Absorption and adsorption 20 Annonaceae 19 Phytochemicals 19 Research 19 Composition 18 Palm oil 18 Plants 18 Copper 17 Botanical chemistry 16 Measurement 15 DNA 14 High performance liquid chromatography 14 Lauraceae 14 Materials 14 Oil palm 14 Pollution 14 Surface active agents 14 Antioxidants 13 Mass spectrometry 13 Toxicology 13