Sittichai KoontongkaewBoonyanit ThaweboonRungsunn TungtrongchitrMahidol University2018-02-272018-02-271986-01-01Toxicity Assessment. Vol.1, No.4 (1986), 419-42910982256088481812-s2.0-0022904935https://repository.li.mahidol.ac.th/handle/20.500.14594/9873Dimethyl sulfoxide extracts of betel nut (100g/L) and betel leaf (100g/L), and methanol and water extracts of betel nut (100g/L) were found to inhibit dehydrogenase activity of Bacillus subtilis. In contrast betel nut (100g/L) extracted by petroleum ether showed no inhibitory effect. Thin layer chromatography, ultraviolet spectroscopy and total polyphenols estimation indicated that betel nut contained large amounts of polyphenols. On the basis of toxicity assessment, the results implied that betel nuts and betel leaves contained a hydrophilic element which was toxic to living cells. Copyright © 1986 Wiley Periodicals, Inc., A Wiley CompanyMahidol UniversityPharmacology, Toxicology and PharmaceuticsArticleSCOPUS10.1002/tox.2540010404