Biokatalitiese komponente in sade van enkele spesies uit die families Fabaceae en Caryophyllaceae

[摘要] English: In the south of Germany it was observed that species of the families Fabaceae and Caryophyllaceaesurvived an unknown environmental catastrophy while this was not the case with plant species fromother families (Huster, Personal observation). Seed suspensions of some species belonging to thesetwo families were applied to agricultural crops as foliar sprays, improving both the vegetativegrowth and yield of the crops. This supplied the rationale to test the seeds of South African speciesfrom these two families for its biocatalytic properties. Seeds of two species from each of thementioned families namely Acacia karroo and Acacia erioloba from the family Fabaceae as well asPollichia campestris and Dianthus basuticus from the family Caryophyllaceae, were subsequentlyscreened for similar biocatalytic properties.Not much information on the chemical composition of these four plant species and nothing at allabout their biocatalytic activity could be found in literature. In the study that followed biocatalyticactivity was confirmed in a seed suspension of Acacia erioloba (Fabaceae) as it increased therespiration rate of a mono culture yeast cells as well as root growth of Cress-seedlings markedly.Activity directed liquid-liquid extraction of the A. erioloba seed suspension revealed that most ofthe biocatalytic activity was present in the ethyl acetate fraction. Further column chromatographicfractionation of the ethyl acetate fraction produced 13 combined column fractions of which twowere active. Activity directed preparative thinlayer chromatographic purification of compounds inone of these fractions produced one active compound that was identified as 2-ethylhexylphtalate bymeans of nuclear magnetic resonans (NMR) spectroscopy. From the second columnchromatography fraction six compounds were isolated but in such small amounts that NMRanalysis was not possible. By means of colour reagents it was, however, established that three ofthe six compounds were alkaloids, two were terpenoides and one a coumarin. It is recommended that active components in this group should be identified in a follow-up study by initially extracting much more seed material.

[发布机构] University of the Free State