Secondary metabolites during ontogenetic phase of reproductive structures in Hypericum maculatum

Abstract

Abstract:The distribution patterns of flavonoids hyperoside, isoquercitrin, quercitrin, quercetin, I3,II8-biapigenin and naphtodianthrones hypericin and pseudohypericin were studied in reproductive structures during ontogenetic phase of flowering in Hypericum maculatum CRANTZ. Considerable differences in the content of these secondary metabolites, in the particular flower parts were found. The content of all the metabolites studied is stable during the whole period of flowering in green flower parts (sepals). In petals, stamens and pistils their content undergoes considerable change associated with the biological functions of particular metabolites. The most conspicuous changes during ontogenetic phase of flowering were the decrease of hyperoside and isoquercitrin content in petals (average content in buds 1.589 mg g −1 dry weight, average content in overblown flowers 0.891 mg g −1 dry weight), the decrease of the I3,II8-biapigenin content in stamens (in buds 1.189 mg g −1 dry weight, in overblown flowers 0.319 mg g −1 dry weight), and the increase of hypericin and pseudohypericin content in both petals (total average content of hypericins in the buds 0.547 mg g −1 dry weight; in overblown flowers 0.792 mg g −1 dry weight) and stamens (in buds 0.189 mg g −1 dry weight; in overblown flowers 0.431 mg g −1 dry weight). Hypericins are absent in the pistil. The flavonoids hyperoside and isoquercitrin, the content of which decreased during ontogenetic phase of flowering, reach the highest contents in the pistil.

Host metabolite producing endophytic fungi isolated from Hypericum perforatum

“…perforatum , the average amounts of hypericin and emodin were found to be 3330 ng/mg (dry weight) and 190 ng/mg (dry weight), which could significantly decrease during a cold acclimation period and remained unchanged after the exposure of plants to dehydration and exogenous abscisic acid treatment [63]. Furthermore, the amount varied within the taxonomical category [64], seasons of harvesting [65], different plant structures [66] and the ontogenetic phases [67]. It is interesting that the emodin content of fungi is higher than that of the hypericin, which is vice versa in plants.…”

Pseudohypericin and Hyperforin in Hypericum perforatum from Northern Turkey: Variation among Populations, Plant Parts and Phenological Stages

“…Therefore, investigations on ontogenetic variation of secondary metabolites from different classes have received considerable interest from plant scientists over several decades. In particular, growth and development of the reproductive parts in Hypericum plants is generally followed by acceleration of secondary metabolism resulting in enhanced accumulation of different secondary metabolites such as hypericin, rutin, quercetin, isoquercetin, hyperoside in H. perforatum (Kazlauskas and Bagdonaite 2004; Çirak et al 2007b), H. brasiliense (Abreu et al 2004), H. maculatum (Martonfi et al 2006), total phenolics in H. perforatum, H. pruinatum and H. aviculariifolium (Ayan et al 2006) and hyperforin in H. perforatum (Büter and Büter 2002; Couceiro et al 2006). Our findings in the present study confirmed this phenomenon.…”

“…However, detecting genotypic variation in the concentration of secondary metabolites is not sufficient to make a substantial conclusion unless other sources of variation are clarified (Walker et al 2001). Because, variation in secondary metabolite concentrations among accessions of H. perforatum may be influenced not only by variance of genotype but also by other factors such as morphologic composition of plant material and the phenological stage in which plants are harvested (Sirvent et al 2002; Martonfi et al 2006). In our previous studies, we documented morphologic, phenologic and population variability of hypericin and several flavonoids (Çirak et al 2007a, b) in H. perforatum growing in Turkey.…”

EFFECT OF THE VEGETATION CYCLE ON TOTAL PHENOLIC AND FLAVONOID COMPOUNDS IN Hypericum perforatum L. AND Melissa officinalis L. COLLECTED IN MONTENEGRO

“…Phenolics and flavonoids, which are responsible for the biological activities of Hypericum perforatum L., can often be found in the leaves and flowers of a plant (Zobayed et al, 2006) and the disposal model of some flavonoids in plants reproductive complex during the flowering stage was also studied in a related Hypericum species (Mártonfi, 2006). H. perforatum L. is well recognized when it comes to flavonoids content (quercetin and kaempferol at the first place) (Nahrstedt and Butterweck, 2010) which are found in its leaves as glycosides located in special compartments of the cells of epidermis, and which are responsible for UV-protection (Germ, et al, 2010).…”