Esameldin E. Elgorashi

Investigation of the antimutagenic effects of selected South African medicinal plant extracts

Dichloromethane extracts from different parts of Rhamnus prinoides, Ornithogalum longibracteatum, Gardenia volkensii, Spirostachys africana, Diospyros whyteana, Syzigium cordatum and Prunus africana were investigated for mutagenic and antimutagenic effects in Salmonella/microsome and micronucleus tests. None of the extracts tested in the Ames test were found to induce mutations or to modify the effect of the mutagen 4-nitroquinoline-oxide (4NQO). In the micronucleus test, extracts from twigs/bark of R. prinoides, twigs of D. whyteana, P. africana and S. cordatum significantly lowered the effect of the mutagen mitomycin C (MMC). Extracts from twigs/bark of G. volkensii and S. africana were genotoxic in the micronucleus test, while extracts of O. longibracteatum leaves potentiated the genotoxicity of MMC. This preliminary investigation shows that plant extracts used in traditional medicine may have particular effects with regard to mutagenicity and antimutagenicity indicating careful use in some instances and the need to isolate their active principles for further research.

Alkaloids from Crinum bulbispermum

In addition to crinamine, bulbispermine, 3-O-acetyl hamayne and 6-hydroxycrinamine, three new alkaloids 8α-ethoxy precriwelline, N-desmethyl 8α-ethoxy pretazettine and N-desmethyl-8β-ethoxy pretazettine were isolated from Crinum bulbispermum. The structures of the new alkaloids were established by specroscopic techniques.

Organ-to-organ and seasonal variation in alkaloids from Crinum macowanii

The distribution and seasonal variation of alkaloids from Crinum macowanii were investigated. The alkaloids lycorine, 1-O-acetyllycorine, crinine, powelline, crinamine, crinamidine, 3-O-acetylhamayne, 1-epideacetylbowdensine and cherylline were isolated from this plant using gas chromatography. Significant organ-to-organ variations were detected for the alkaloids crinine, lycorine, powelline, crinamidine, 3-O-acetylhamayne and crinamine. Crinine, crinamidine and 1-epideacetylbowdensine showed significant seasonal variation.

Alkaloids from Cyrtanthus falcatus

The alkaloids papyramine, epipapyramine, maritidine, O-methylmaritidine and tazettine were isolated from the methanolic extracts of the bulbs of Cyrtanthus falcatus. The structures of these alkaloids were determined by spectroscopic methods.

Variation among three Crinum species in alkaloid content

Abstract Dilute hydrochloric acid solution extraction, followed by gas chromatographic analysis, was used to investigate the interspecific variation in the alkaloid content of three Crinum species, C. bulbispermum , C. macowanii , and C. moorei over two consecutive years. The identified alkaloids showed that C. moorei had the highest levels of all individual alkaloids, except crinamine, when compared to C. bulbispermum and C. macowanii . The detected alkaloids can be used to make a chemotaxonomic distinction between C. moorei on the one hand and C. bulbispermum and C. macowanii on the other. The results suggest that C. macowanii is more closely related to C. bulbispermum .

Organ-to-organ and seasonal variations of alkaloids from Crinum moorei

Dilute HCl extraction followed by gas chromatography were used to determine the distribution and seasonal variation of alkaloids in Crinum moorei . Significant organ-to-organ variations were detected for the individual alkaloids crinine, lycorine, powelline, undulatine, crinamidine, 1- O -acetyllycorine, 1-epideacetylbowdensine and 3- O -acetylhamayne. Alkaloids which showed significant seasonal variations were lycorine, crinine and undulatine.