Hydroquinone; A Novel Bioactive Compound from Plant-Derived Smoke Can Cue Seed Germination of Lettuce

Abstract

Plant-derived smoke has been known to play an important role in distribution and growth of vegetation. Using a proficiently designed furnace, we extracted smoke from the leaves of four plant viz. <i>Helianthus annuus</i>,<i>Aloe vera</i>,<i>Ginkgo biloba</i>, and <i>Cymbopogon jwarancusa</i>. Smoke dilutions obtained from these plants were obtained in different concentrations to identify potential lettuce growth promoting smoke solution. Results revealed that smoke obtained from <i>G. biloba</i> significantly enhanced the lettuce seed germination. This solution was then partitioned into ethyl acetate, dichloromethane, <i>n</i>-hexane, chloroform and ether fractions. Ethyl acetate fraction was found to be potent to enhance seed germination. This fraction was subjected to column chromatography and spectroscopic techniques to obtain compound <b>1</b>. This compound was identified as hydroquinone using 1D and 2D NMR techniques. At low concentrations (5, 10, and 20 ppm), compound <b>1</b> enhanced the lettuce seed germination; however, higher concentrations inhibited its growth as compared to control.