The search for germination stimulants in plant-derived smoke extracts

Abstract

Aqueous extracts of plant-derived smoke stimulates seed germination. To isolate the active compound(s), smoke extracts of Passerina vulgaris and Themeda triandra were subjected to bioassay-guided fractionation. Purification steps included liquid-liquid partitioning, semi-preparative HPLC, two TLC systems and analytical HPLC. Each purification step was examined using the lettuce seed germination bioassay. Biologically active fractions were selected for further purification. Active fractions from the last HPLC purification step were analysed by high-resolution GC-MS. Twelve compounds were identified, of which seven were present in both the P. vulgaris and T. triandra extracts. Four of the compounds that were commercially available were tested in the lettuce seed bioassay and were found to be inactive. Waterekstrakte verkry van plantrook stimuleer saadontkieming. Om die aktiewe verbindings in rook te isoleer is rookekstrakte van Passerina vulgaris en Themeda triandra onderwerp aan biotoets-gereguleerde fraksionering. Suiweringstappe het vloeistof-vloeistof partisie, semi-preparatiewe HPLC, twee TLC stelsels en analitiese HPLC ingesluit. Elke stap is ondersoek met die slaaisaad-biotoets. Biologies-aktiewe fraksies het verdere suiwering ondergaan. Aktiewe fraksies van die laaste HPLC stap is onderwerp aan hoë resolusie GC-MS. Twaalf verbindings is geïdentifiseer waarvan sewe in beide die P. vulgaris en T. triandra ekstrakte gevind is. Vier van hierdie verbindings wat kommersieel bekom kan word was onaktief in die slaaisaad-biotoets.