Screening of phytochemicals and toxicity of medicinal plants,<i>Dillenia</i>species, reveals potential natural product resources

Abstract

Plants in genus Dillenia have traditionally been consumed as foods and used for cancer and diarrhea treatments. Crude hexane extracts of nine species, D. aurea, D. excelsa, D. grandifolia, D. ovata, D. parviflora, D. philippinensis, D. pulchella, D. reticulata, and D. suffruticosa were analyzed for chemical contents via gas chromatography-mass spectrometry, and for their cytotoxicity and genotoxicity on leukocytes via cell counting and comet assays. Oleamide, a chemopreventive agent which acts against Alzheimer's disease, enhances memory function and promotes sleep, was found at the highest amount (18.05–75.60%). The other components discovered in high amounts were squalene and vitamin E. The IC50 of all studied species was higher than 430 µg/mL. Comet assay indicated insignificant DNA damage (p > .05). These results indicate that the plants containing a high amount of useful phytochemicals are nontoxic to normal human cells, thus may be safely applied for the treatment of Alzheimer's disease and other related conditions. Practical applications Oleamide has an important role in living things, especially in humans. Its functions are, improved memory recovery, induced deep sleep and appetite in elders. Based on the principles of phytotherapy, a plant species actually contains several pharmacological compounds in a different quantity; a medicinal reading should be in a single unit. In agreement with a high quantity of oleamide in Dillenia species, many species would be selected to produce natural products in convenient forms, and in drug discovery, because this serves as active principles in drugs as well as templates for synthesis of new drugs. In this research, seven out of nine species including Dillenia aurea, D. excelsa, D. grandifolia, D. ovata, D. parviflora, D. philippinensis, and D. reticulata contained high amounts of oleamide, were expected to release single medicinal activity, and show no cytotoxicity and genotoxicity. Accordingly, they should effectively be made available in modified forms in order to be health products.