title: Acetic acid acts as an elicitor exerting a chitosan-like effect on xanthone biosynthesis in Hypericum perforatum L. root cultures.
abstract: Acetic acid acts as a signal molecule, strongly enhancing xanthone biosynthesis in Hypericum perforatum root cultures. This activity is specific, as demonstrated by the comparison with other short-chain monocarboxylic acids. We have recently demonstrated that Hypericum perforatum root cultures constitutively produce xanthones at higher levels than the root of the plant and that they respond to chitosan (CHIT) elicitation with a noteworthy increase in xanthone production. In the present study, CHIT was administered to H. perforatum root cultures using three different elicitation protocols, and the increase in xanthone production was evaluated. The best results (550 % xanthone increase) were obtained by subjecting the roots to a single elicitation with 200 mg l(-1) CHIT and maintaining the elicitor in the culture medium for 7 days. To discriminate the effect of CHIT from that of the solvent, control experiments were performed by administering AcOH alone at the same concentration used for CHIT solubilization. Unexpectedly, AcOH caused an increase in xanthone production comparable to that observed in response to CHIT. Feeding experiments with (13)C-labeled AcOH demonstrated that this compound was not incorporated into the xanthone skeleton. Other short-chain monocarboxylic acids (i.e., propionic and butyric acid) have little or no effect on the production of xanthones. These results indicate that AcOH acts as a specific signal molecule, able to greatly enhance xanthone biosynthesis in H. perforatum root cultures.
authors.affiliation: Department of Environmental Biology, Sapienza University of Rome, Rome, Italy. alessio.valletta@uniroma1.it.
authors.forename: Alessio
authors.initials: A
authors.lastname: Valletta
authors.affiliation: Department of Environmental Biology, Sapienza University of Rome, Rome, Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: De Angelis
authors.affiliation: Department of Environmental Biology, Sapienza University of Rome, Rome, Italy.
authors.forename: Camilla
authors.initials: C
authors.lastname: Badiali
authors.affiliation: Department of Environmental Biology, Sapienza University of Rome, Rome, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Brasili
authors.affiliation: Department of Chemistry, Sapienza University of Rome, Rome, Italy.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Miccheli
authors.affiliation: Department of Chemistry, Sapienza University of Rome, Rome, Italy.
authors.forename: Maria Enrica
authors.initials: ME
authors.lastname: Di Cocco
authors.affiliation: Department of Environmental Biology, Sapienza University of Rome, Rome, Italy.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Pasqua
mesh_terms: D019342:Acetic Acid / Q000378:metabolism* / Q000494:pharmacology; D002264:Carboxylic Acids / Q000494:pharmacology; D048271:Chitosan / Q000008:administration & dosage*; D020902:Hypericum / Q000187:drug effects* / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects* / Q000378:metabolism; D015398:Signal Transduction; D044004:Xanthones / Q000378:metabolism*
chemical_list: D002264:Carboxylic Acids; D044004:Xanthones; D048271:Chitosan; C009689:xanthone; D019342:Acetic Acid
keywords: Acetic acid; Chitosan; Elicitor; Hypericum perforatum; Root cultures; Xanthones