Polysaccharide elicitors enhance phenylpropanoid and naphtodianthrone production in cell suspension cultures of Hypericum perforatum

Abstract

Hypericum perforatum cell suspensions were evaluated for their growth, phenylpropanoid and naphtodianthrone productions, and antioxidant activity after treatments with polysaccharide elicitors chitin (CHI), pectin (PEC) and dextran (DEX). Polysaccharide elicitation of cell cultures showed a considerable improving effect on phenylpropanoid production (phenolics, flavonoids, flavanols and anthocyanins) during the post-elicitation period. Even that enhanced phenylpropanoid production was related to growth suppression of CHI elicited cells, PEC and DEX were presented as effective elicitors without loss of cell biomass. Phenylpropanoid accumulation in elicited cells was correlated to markedly higher enzyme activities of phenylalanine ammonia lyase and chalcone-flavanone isomerase. Cell cultures were found to respond rapidly towards the applied elicitors through an early stimulation of both naphtodiantrones, hypericin (HYP) and pseudohypericin (PHYP). The CHI was proposed as a much more prominent elicitor in stimulation of HYP and PHYP levels in cell suspensions. All tested polysaccharide elicitors stimulated non-enzymatic antioxidant properties in cell extracts indicating the potential role of phenolic compounds as effective antioxidants. With regards to the antioxidant enzymes, an up-regulation of peroxidase and catalase activities was observed in PEC and DEX elicited cells, whereas CHI did not give any stimulatory effect on enzymatic activities. These findings suggest the involvement of an efficient antioxidant defense system in the adaptive response of cells to polysaccharide elicitation. Altogether, these results indicated that H. perforatum cells elicited with polysaccharides represent a promising experimental system for enhanced production of phenylpropanoids and naphtodianthrones.

Abiotic and Biotic Elicitors–Role in Secondary Metabolites Production through In Vitro Culture of Medicinal Plants

“…Chitosan enhanced the production of trans-resveratrol and viniferins in the cell system of V. vinifera [91]. Chitin induced the phenylpropanoid and naphtodianthrone production in cell suspension cultures of H. perforatum [114].…”

Does phenotyping of Hypericum secondary metabolism reveal a tolerance to biotic/abiotic stressors?

“…The elevated accumulation of flavonols, hydroxycinnamic acids, xanthones, and other phenolic compounds stimulated by (poly)saccharides in in vitro cultures of Hypericum spp. proves the universal role of saccharides-based elicitation (Kirakosyan et al, 2000;Gadzovska-Simic et al, 2014;Gadzovska-Simic et al, 2015a). The elicitors derived from Aspergillus niger and F. oxysporum stimulated the biosynthesis of phenylpropanoids or flavonoid glycosides in several Hypericum spp.…”

“…The elicitors derived from Aspergillus niger and F. oxysporum stimulated the biosynthesis of phenylpropanoids or flavonoid glycosides in several Hypericum spp. (Azeez and Ibrahim, 2013;Gadzovska-Simic et al, 2015b) The biotic/abiotic stress signaling pathways comprising the stress perception, signal transduction, and expression of specific stress-related genes resulting in modulation of plant primary and secondary metabolism. Metabolites highlighted by an asterisk are the markers with predictive value in cold-stress response of Hypericum species.…”

Plant Metabolites in Plant Defense Against Pathogens

“…These, in turn, induced the synthesis of phytoalexins (hydroxycoumarin, scopoletin, and umbelliferone), and upon isolating the glycoprotein produced the synthesis of coumarin by 80%. On the other hand, oligogalacturonic acids are found in the cell wall of the plant inducing the biosynthesis of phytoalexins, whereas chitin is found in the cell wall of fungi, generating signaling factors in plants such as Hypericum perforatum production stress in the plant and increasing the production of phenolic compounds for their defense against pathogens [39,42]. Rhizobacteria function as modelers of secondary metabolites with pharmacological activity.…”