Some chromatographic characteristics of germination stimulants in plant-derived smoke extracts

Abstract

Plant-derived smoke extracts stimulate the germination of many different seeds. the present report explains steps to determine some of the chemical characteristics of the compounds concerned. Grand Rapids lettuce seeds were used as a bioassay because smoke-derived extracts overcome their light-sensitivity. The active compounds were partitioned into ethyl acetate, separated by various TLC systems and fractionated by reverse phase HPLC. They are stable surviving a series of chromatographic steps and are very active biologically. In order to ascertain their chemical properties it was necessary to use a range of dilutions after each isolation step. It would appear that similar types of compounds are present in smoke extracts derived from different plant material.

Burning vegetation produces cyanohydrins that liberate cyanide and stimulate seed germination

“…3g). Furthermore, the cyanohydrin analogues glycolonitrile (3), acetone cyanohydrin (4), 2,3,4-trihydroxybutyronitrile (5) and mandelonitrile (6) (Fig. 1a) were also active ( Fig.…”

“…5c). When compared with racemic mandelonitrile in the presence of α-hydroxynitrile lyase, naturally present in almonds (Prunas amygdalus, Rosaceae), in the presence of racemic mandelonitrile (6), where the natural substrate is (R)-mandelonitrile 24 , significant conversion to free cyanide and benzaldehyde was noted within minutes (Fig. 5d).…”

“…Smoke derived from burning plant material is a key agent responsible for promoting seed germination following fire 3 and increases seed germination of an estimated 1,200 phylogenetically diverse plant species 4 . Smoke contains thousands of different compounds and there have been many attempts to identify the active compound(s) [5][6][7][8][9][10] . In 2004, a potent bioactive compound in cellulose-and plant-derived smoke was identified as 3-methyl-2H-furo [2,3-c]pyran-2-one (1) (Fig.…”

From little things big things grow: karrikins and new directions in plant development

“…Clues about the chemical nature of smoke compounds with the capacity to stimulate seed germination came from early experiments with 'liquid smoke' or 'smokewater', a complex solution of combustion products generated by bubbling smoke through water (Baldwin et al 1994;Baxter et al 1995;van Staden et al 1995). The presence of active compounds in smoke indicated that they were at least partially volatile, and chromatography-based fractionation experiments revealed that several different compounds are active, depending on the starting material (Baldwin et al 1994;van Staden et al 1995).…”

“…The presence of active compounds in smoke indicated that they were at least partially volatile, and chromatography-based fractionation experiments revealed that several different compounds are active, depending on the starting material (Baldwin et al 1994;van Staden et al 1995). Despite these promising advances, discovery of an active compound was not made until 2004, using bioassay-guided fractionation of smokewater, followed by gas chromatography-mass spectrometry and nuclear magnetic resonance techniques for structural elucidation.…”