Differential phenolic accumulation in two Hypericum species in response to inoculation with Diploceras hypericinum and Pseudomonasputida

Abstract

Cirak C., Radusiene J., Aksoy H.M., Mackinaite R., Stanius Z., Camas N., Odabas M.S. (2014): Differential phenolic accumulation in two Hypericum species in response to inoculation with Diploceras hypericinum and Pseudomonas putida. Plant Protect. Sci., 50: 119-128.The genus Hypericum L. (St. John's-wort, Hypericaceae) has received scientific interest in recent years, because it is a source of a variety of bioactive compounds including the phenolics. We determine whether the typical phenolic constituents of Hypericum plants, namely chlorogenic acid, rutin, hyperoside, isoquercetine, quercitrine, and quercetine, may be implicated as part of an inducible plant defence response in two St. John's-wort species, Hypericum perforatum L. and Hypericum triquetrifolium Turra. To achieve this objective, greenhouse-grown plantlets were inoculated with the fungal pathogen Diploceras hypericinum and the plant growth promoting bacterium Pseudonomas putida. Phenolic compounds levels of the Hypericum plantlets increased significantly in response to inoculation with both organisms. So far, little effort has been dedicated to investigate whether phenolic compounds are inducible by pathogen/herbivore attack or if they could play a role in plant defence. Results from the study indicate that the phenolic compounds investigated could be involved in the plant defence system and implicated as part of an inducible plant defence response in both St. John's Wort species.Keywords: fungal pathogen; Hypericum perforatum; Hypericum triquetrifolium; phenolic compounds; plant defence; bacterial infectionHypericum perforatum L. is a well-known traditional medicinal plant that has been used for centuries for the treatment of several diseases, such as skin lesions, eczema, burns and microbial, inflammatory, and psychological disorders (Sanchez-Mateo et al. 2002). The crude extract of H. perforatum is now widely used in Europe as a drug for the treatment of depression. Proven photodynamic, antiviral, antiretroviral, and antitumor effects of Hypericum extracts also suggest using this plant in in the case of Acquired Immune Deficiency Syndrome (AIDS) and cancer treatments (Guedes & Eriksson 2005). Hypericum triquetrifolium Turra is another widespread species of Hypericum genus. It has traditionally been used in the treatment of burns and gastrointestinal disease in Turkish folk medicine (Baytop 1999). Results from recent studies reporting anti-inflammatory (Ozturk et al. 2002), antibacterial (Pistelli et al. 2005, antifungal (Fraternalea et al. 2006), antioxidant, and cytotoxic (Conforti et al. 2007) activities of H. triquetrifolium sign out the great potential of this species as a promising medicinal plant. 120Vol. 50, 2014, No. 3: 119-128 Plant Protect. Sci.Chemistry of Hypericum genus has been extensively investigated and it has been shown that methanolic extract from the aerial parts of Hypericum plants typically contains hypericins, hyperforins, and several phenolic compounds, altogether good candidates for the activity of the drug (Pat...

Factors affecting the variation of bioactive compounds inHypericumspecies

“…The results of these studies indicate that blooming is the most appropriate harvesting time to provide the highest level of secondary metabolites (Odabas et al, 2008(Odabas et al, , 2009b. The increasing accumulation of secondary metabolites such as hypericins and phenolic compounds during flowering can be attributed to reproductive adaptations within internal regulation of plant cells to provide protection against plant pathogens and herbivores (Cirak et al, 2014a;Crockett & Boeve, 2011), higher ultraviolet B (UV-B) radiation, and other environmental stressors during propagule reproduction (Falcone Ferreyra et al, 2012).…”

“…It was reported that the content of phenolics such as luteolin, mangiferin, hyperoside, mangostin, isoquercitrine, quercetine, and their derivatives has increased in H. perforatum cultures as a response to Colletotrichum gloesporioidies infection, which is one of the most common fungal pathogens inducing bitter rot of many crops (Conceicao et al, 2006). Moreover, Cirak et al (2014a) described the role of chlorogenic acid, rutin, hyperoside, isoquercetine, quercitrine, and quercetine as part of an inducible plant defense reaction and reported increasing levels of each compound in response to inoculation with the fungal pathogen D. hypericinum and plant growth-promoting bacteria Pseudomonas putida in H. perforatum and H. triquetrifolium. The enriched accumulation of phenolic compounds has been reported as a genotype response to pathogen infections by upregulation genes-encoding enzymes involved in the phenylpropanoid pathway leading to the synthesis of these compounds (Foster-Hartnettet al, 2007).…”

The effects of salt and drought stress on phenolic accumulation in greenhouse-grown Hypericum pruinatum

“…The salt doses with different levels of water availability were applied 13 times in accordance with the allowed depletion. The experimental design was a factorial experiment in completely randomised plots with 3 replications, each consisting of 5 pots (Cirak et al, 2005(Cirak et al, , 2014a. Plantlets were harvested at the end of 39 th day of experiment when severe wilting was observed in pots treated with higher salt doses.…”

Effect of Salt Stress and Irrigation Water on Growth and Development of Sweet Basil (Ocimum basilicum L.)

“…To create salt stress treatments, NaCl, CaCl 2 and MgCl 2 salts were used. Treatments were arranged as S0 (0.4 dS/m), S1 (1.0 dS/m), S2 (2.5 dS/m), S3 (4.0 dS/m) and finally S4 (8.0 dS/m) as recommended by Cirak et al (2014). To create water stress treatments, initially crop water requirement (W) was determined through weighing the control pots.…”