Showing papers in "Natural product sciences in 1995"

Screening and Isolation of Antibiotic Resistance Inhibitors from Herb Materials. I.-Resistance Inhibition of 21 Korean Plants

Abstract: Staphylococcus aureus SA2, which was isolated from patient, is resistant to 10 usual antibiotics. The methanolic extracts of 21 well-known herb materials were combined with 10 antibiotics and applied to cheek inhibitory effects on the resistance of S. aureus SA2. The hexane fractions from methanolic extracts of Acori graminei Rhizoma and Anethi Fructus had most potent activity to inhibit the resistance of the bacteria when combined with ampicilin or chloramphenicol.

Tumour promoting activity of plants used in Malaysian traditional medicine.

Abstract: One hundred plants in 43 families used in Malaysian traditional medicine were screened for tumour promoting activity using two methods, the technique of activation of latent Epstein-Barr Virus (EBV) in Raji cells and the irritation test on mouse ear. Extracts of only eight plants belonging to the Euphorbiaceae were found to possess EBV activation factor and to give a positive irritation test in mouse ear. These plants included Euphorbia tirucalli L., E. splendes, Jatropha podagrica, J. gossypyfolia L., Pedilanihus tithymaloides (L.) Poitt., Croton argyratus Bl., Exocoecaria agallocha L. and Codiaeum variegatum (L.) Bl. Seven of these plants are used internally in Malaysian traditional medicine. As such, they pose potential danger in the promotion of initiated cells of the mucosal tissue towards disease. Further studies are required to assess the epidemiological impact of these plants in the development of disease.

Pharmacognostic profile of trigonella seed and its hypoglycaemic activity

Abstract: Pharmacognostic study was carried out on the seeds of Trigonella foenumgraecum L. (fenugreek) in order to establish its pharmacognostic characteristics. In view of its renewed interest as a dietary supplement among the local inhabitants afflicted with diabetes, its hypoglycaemic activity in normal as well as diabetic rats was also investigated. Oral glucose tolerance test showed that a suspension of the powdered trigonella seed inhibited the increase in blood glucose levels in normal rats that had been treated with an oral glucose load prior to the test. A reduction in the blood glucose levels was also observed when a suspension of the powdered seed was given by gastric intubation to the streptozotocin-induced diabetic rats. These findings suggested that trigonella seeds possessed some hypoglycaemic activities that might be useful to the diabetics.

Cytotoxic constituents from the roots of Bryonia alba L.

Abstract: Two cucurbitane-compounds were isolated from the roots of Bryonia alba L. and the chemical structures were established as 19-norlanost-5-ene-3,11,22-trione-2β, 16α,20β,25-tetrahydroxy-9-methyl (23,24-dihydrocucurbitacin D) and 2-O-β-D-glucopyranosyl 19-norlanost-5-ene-3,11,22-trione-2β,16 α,20β,25-tetrahydroxy-9-methyl (arvenin IV), respectively, on the basis of chemical and spectral methods. Both of the compounds showed cytotoxic activity against cancer cell lines, A549, SK-MEL2, COLO 205 and L1210.

Chemical constituents from Mussaenda pubescens

Abstract: A new triterpenoid saponin named Mussaendoside F(1), along with five known compounds (2-6) were isolated from aerial part of Mussaenda pubescens.

Isolation of Cytotoxic Compounds from the Leaves of Xanthium strumarium L.

Abstract: MeOH extract of the leaves of Xanthium strumarium L. were found to have cytotoxic activities against five human tumor cell lines. Cytotoxicity-guided chromatographic fractionation led to the isolation of the containing sesquiterpenes, xanthatin, 8-epi-xanthatin and 8-epi-tomentosin. 8-epi-Xanthatin was found to be far more cytotoxic than 8-epi-tomentosin, which lacks the conjugated enone moiety present in 8-epi-xanthatin.

Isolation of Ethanol Metabolizing Enzyme Inhibitors from Aloe spp.

Abstract: In the course of evaluation of hepatoprotective components against alcohol-induced toxicity from Aloe spp., the methanol extract was found to cause a significant inhibition of rat liver cytosolic alcohol dehydrogenase activity. Systematic fractionation of active tractions monitored by bioassay led to isolation of four compounds; aloe-emodin, aloenin, ethylidene-aloenin and , which were estimated as active principles for inhibition of c-ADH and c-ALDH activities in vitro.

A Chemotaxonomic Study on Euphorbiaceae in Korea

Abstract: A chemosystematic study on euphorbiaceous plants in Korea has been performed by using phenolic constituents. The phenolic characteristics of subfamilies, genera and species were well distinguished from one another. Hydrolyzable tannins as constituents were considered to be a valuable taxonomic character in elucidating systematic relationships among the related taxa whereas flavonoids could be used in the classification of infraspecific taxa in this family. The phenolic fingerprints of each of the plants would be considered as a good tool to identify the species. In comparison with the morphological classification system, the chemical relationship supported the subfamilial system of Webster (1975) and the further division of Euphorbia sensu lato by Hurusawa (1954).