Effect of plant growth regulators on growth patterns and enzymatic antioxidant activities in Hypericum calycinum shoot cultures

Open Access JournalHypericum calycinum L. (section Ascyreia) is a species of the Hypericum genus, relative to the medicinal plant H. perforatum (St. Jonn’s worth). Unlike the widely studied H. perforatum, it is characterized by the lack of hypericins production. However, research has revealed its commensurable antidepressant activity, as compared with the latter species, and shown the presence of polyphenolics with marked radical scavenging activity. In order to develop an in vitro system with the potential of a novel source of bioactive constituent’s characteristic for the Hypericum genus, we initiated in vitro cultures of H. calycinum. In the present work we studiy the effect of exogenous BA and IBA treatments on the developmental patterns, enzymatic and non-enzymatic antioxidant defence of hypericin non-producing Hypericum calycinum shoot cultures. It was shown that supplementation of PGR led to stimulation of phenylalanine ammonia-lyase and superoxide dismuthase, as well as non-enzymatic antioxidant glutathione. However, they inhibited glutathione reductase, as well as lowered the levels of fl avonoids, ascorbate and dehydroascorbate in comparison with plant growth regulators-free control. Further on, it was established that elevation of IBA concentration slightly stimulated axillary shoot formation and shoot length, but inhibited polyphenolic levels in vitro. These results are in agreement with our previous results of interrelations between biomass formation and polyphenolics production in other Hypericum species in vitro. An in vitro culture system optimization is in progress in order to increase biomass  production and retain biosynthetic capacity of the species.

In vitro culture development and polyphenolics production of Artemisia alba Turra

Open Access Journal Second National Youth Conference “Biological sciences for a better future”, Plovdiv, October 30-31, 2015.Artemisia alba Turra is an aromatic plant, characterized by a high variability of the terpenoid profile of its essential oil. In previous research, in vitro shoots of the plant were developed, aiming at elucidation of the effects of plant growth regulators on essential oil production. Though less information is available in literature regarding the non-volatile components of the plant, a number of works report on the presence of compounds with coumarin, flavonoid and sesquiterpene structure which might attribute to the pharmacological activity of the plant. In the present work, different lines of differentiated and non-differentiated in vitro cultures of the plant have been developed in solid and liquid media. The potential of these lines to produce compounds with phenolic and flavonoid structure has been studied. In differentiated shoot cultures, low benzyl adenine (BA) concentration alone or in combination with different indole-3-butyric acid (IBA) concentrations increased the polyphenolic levels as compared with plant growth regulators free control, as well with media with high BA alone or combined with IBA. The content of these compounds was also low when IBA was applied alone. In non-differentiated cell aggregate cultures, 1-naphthaleneacetic acid (NAA) in combination with BA significantly increased polyphenolics as compared with IBA. Observations on the morphology of the aggregates formed in the two media suggested that the more compact structure and larger size of aggregates as a result of NAA supplementation might be decisive for the higher polyphenolics productivity, as compared with IBA

International Seminar of Ecology – 2022

International Seminar of Ecology – 202

Plant Tissue Culture and Secondary Metabolites Production

Plants have developed a complex biochemical system for interacting and coping with dynamic environmental challenges throughout their whole life [...

Light and auxin treatments affect morphogenesis and polyphenolics productivity in Artemisia alba Turra cell aggregates in vitro

Artemisia alba Turra is an essential oil-bearing shrub, with a Euro-Mediterranean distribution widespread in the south-eastern parts of Europe. Phytochemical investigations have evidenced the presence of volatile mono- and sesquiterpene derivatives, as well as non-volatile sesquiterpenoids, flavonoids and phenolic acids contributing to the anti-inflammatory, antimicrobial, antioxidant and pro-apoptotic activity of different preparations, obtained from the plant. The current research aims at elucidation of the potential for biotechnological polyphenolic compounds productivity of non-differentiated cell lines of the plant. For this purpose, non-differentiated cell aggregates were initiated from either leaf or root explants of the sterile grown plant. They were cultivated either in the dark or at 16/8 h photoperiod in liquid media, supplemented with N6-benzyladenine (BA) as auxin. The cytokinin effects of indole-3-butyric acid (IBA) and 1-naphthalene acetic acid (NAA) were compared. It was established that NAA supplementation was superior to IBA and light treatment – to dark growth conditions in terms of polyphenolics productivity. In addition, NAA supplementation led to better expressed compaction and larger size of the cell aggregates as compared with IBA. The results of the present experiment indicate that secondary metabolites productivity in vitro is a dynamic process closely related to the plant’s growth and development and is in close relation to the interactions of the plant with its environmental conditions