Title
Lignin and polyphenols from vegetal wastes as key modulators of metabolic pathways during plant development
Authors
NARCIS C. ANGHEL

Received July 5, 2015
Published Volume 50 Issue 9-10 October-December
Keywords flax lignin, polyphenols, spruce bark, amylase, catalase, ascorbatoxidase, polyphenol oxidase

Abstract
The development of plants is highly influenced by exogenous substances, which can act as biostimulators or inhibitors of the growth process. Among them, a very large group of aromatic compounds comprising lignins and polyphenols seem to have phytohormonal properties. Based on current knowledge, our objective was to investigate the action of flax lignin and polyphenols extracted from spruce bark upon the development of Phaseolus vulgaris L. plantules, along with their influence upon some enzymatic systems involved in glucidic metabolism and cellular respiration. Our findings show that the tested substances possess phytohormonal activity, translated into higher biomass accumulation by 20 40% compared with the reference and an increased germination capacity on the average by 10-20%. Moreover, when the concentration of the biologically active compound ranged between 0.05 and 0.1 g/L, the increase in the germination capacity, along with biomass accumulation, was related to increased activities of amylase, ascorbatoxidase and polyphenol oxidase, on the average by 15-25% comparative with the reference, with a decreased activity of catalase. The obtained results clearly demonstrate that polyphenols act in a dose dependent manner upon biological media by stimulation of anabolic pathways, which is translated into biosynthesis of proteins and distinguished by biomass accumulation.