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.

Clinopodium nepeta and Clinopodium menthifolium: agronomical and phytochemical potential of two species of calamint

Ein möglicher kommerzieller Anbau von «Kalaminth», auch bekannt als Bergminzen, wurde hinsichtlich des agronomischen und phytochemischen Potentials in den Vegetationsperioden 2014 und 2016 näher untersucht. Verschiedene Herkünfte der Arten Clinopodium nepeta (L.) Kuntze (kleinblütige Bergminze) und Clinopodium menthifolium (Host) Stace (Wald-Bergminze) wurden unter alpinen Vegetationsbedingungen in den Schweizer Alpen angebaut und anschliessend phytochemisch analysiert. Die Ausbeute von getrocknetem Pflanzenmaterial betrug 4 Tonnen/ha ab dem zweiten Jahr. Für beide Arten schwankte der Gehalt an ätherischem Öl zwischen 1 und 1.5% (v/m) in Abhängigkeit von Erntejahr und der Phänologie zum Erntezeitpunkt. Der Hauptbestandteil (>80%) des ätherischen Öls von C. nepeta war Pulegon, und von C. menthifolium war Carvon (33-38%). Im Falle einer Industriekollaboration wäre eine Studie zur Variabilität von Phänotyp und den Sekundärmetaboliten der Schweizerischen Herkünfte angebracht.From 2014 to 2016, the agronomic and phytochemical potential of two commercial accessions of calamint, one of Lesser Calamint (Clinopodium nepeta (L.) Kuntze) and one of Woodland Calamint (Clinopodium menthifolium (Host) Stace) was evaluated in the mountainous climatic conditions of the Swiss Alps. The production of dry whole plants has reached 4 tons/ha from the second year of cultivation. For both species, the essential oil content fluctuated between 1 and 1.5%, depending on the season and on the phenological stage of harvest. The major component of C. nepeta is pulegone (> 80%), and of C. menthifolium is carvone (33 to 38%). In collaboration with the industry, a study of the phenotypic and phytochemical variability of Swiss ecotypes of calamints would be desirable

In situ and in vitro comparative study on the bioproductivity of Arnicae folium et caulis from the northern area of the Romanian eastern carpathians

Arnica montana L. is an important plant bioresource, being traditionally used as medicinal plant, for which the scientific and economic interest remains at a high level. The aim of our study was to evaluate the bioproductivity for Arnicae folium et caulis in terms of biomass and content in biological active compounds originating from the wild populations and in vitro experimental cultures – under controlled environment. In situ biomass production registered variations, probably due to the different environmental features and also to the management strategies for each site. The development of in vitro cultures had as purpose the evaluation of the biomass production and production of plant material for the phytochemical screening. The Arnicae folium et caulis samples harvested from the wild populations have a higher content in phenolic acids than the Arnicae flos from the same area, but the total content in sesquiterpen-lactones was significantly lower. In contrast, the samples originating from the in vitro cultures had a low content in phenolic compounds and a high content in sesquiterpen-lactones, comparable with Arnicae flos

Diastereoselective synthesis of optically active (2R,5R)-hexanediol

Erworben im Rahmen der Schweizer Nationallizenzen (http://www.nationallizenzen.ch)Diastereoselective reduction of diketones with Lactobacillus kefir DSM 20587 was examined. The reduction of both oxo-functions proceeded highly diastereoselectively. (2R,5R)-Hexanediol 3 was produced starting from (2,5)-hexanedione 1 in quantitative yields with enantiomeric excess >99% and diastereomeric excess >99%. The reaction conditions were optimized: maximum yield of (2R,5R)-hexanediol was reached at pH 6, 30°C and with equal amounts of substrate and cosubstrate. The applicability of the system in fed-batch experiments was demonstrated. The feed specific biomass concentration required to reach maximal yield and selectivity in fed-batch mode was determined

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

In-Silico UHPLC method optimization for aglycones in the herbal laxatives aloe barbadensis Mill., Cassia angustifolia Vahl Pods, Rhamnus frangula L. Bark, Rhamnus purshianus DC. Bark, and Rheum palmatum L. Roots

For the European Pharmacopoeia (Ph. Eur.) herbal monograph draft of Cassia angustifolia Vahl. and Cassia senna L. leaves and pods, a safety limitation of aloe-emodin and rhein was proposed, due to toxicological concerns. A quantitative, analytical method of the anthraquinone aglycones in all Ph. Eur. monographed herbal laxatives is of interest. A rational method development for the aglycones aloe-emodin, rhein, emodin, chrysophanol, and physcion in five herbal drugs was realized by using 3D chromatographic modelling (temperature, solvent, and gradient time) and design of experiment (DOE) software (DryLab® 4). A methodical approach suitable for the challenging peak tracking in the chromatograms of the herbal drugs in dependence on the changes in the chromatographic conditions is described by using a combination of mass spectroscopy (MS) data (UHPLC-QDa), UV/Vis-spectra, and peak areas. The model results indicate a low robust range and showed that with the selected chromatographic system, small interferences could not be averted. The separation achieved shows a pure UV/Vis spectrum for all aglycones except for chrysophanol in Aloe barbadensis and emodin in Cassia angustifolia fruit. A gradient with the best resolution of the aglycones in all five drugs is proposed, and its suitability demonstrated for the quantification of aglycones in these herbal drugs

Computational literature-based discovery for natural products research : current state and future prospects

Literature-based discovery (LBD) mines existing literature in order to generate new hypotheses by finding links between previously disconnected pieces of knowledge. Although automated LBD systems are becoming widespread and indispensable in a wide variety of knowledge domains, little has been done to introduce LBD to the field of natural products research. Despite growing knowledge in the natural product domain, most of the accumulated information is found in detached data pools. LBD can facilitate better contextualization and exploitation of this wealth of data, for example by formulating new hypotheses for natural product research, especially in the context of drug discovery and development. Moreover, automated LBD systems promise to accelerate the currently tedious and expensive process of lead identification, optimization, and development. Focusing on natural product research, we briefly reflect the development of automated LBD and summarize its methods and principal data sources. In a thorough review of published use cases of LBD in the biomedical domain, we highlight the immense potential of this data mining approach for natural product research, especially in context with drug discovery or repurposing, mode of action, as well as drug or substance interactions. Most of the 91 natural product-related discoveries in our sample of reported use cases of LBD were addressed at a computer science audience. Therefore, it is the wider goal of this review to introduce automated LBD to researchers who work with natural products and to facilitate the dialogue between this community and the developers of automated LBD systems

Verbascum nigrum : cytotoxicity evaluation in A431 epidermoid carcinoma cells and untargeted LC‐HR‐MS/MS metabolite profiling

The crude methanolic extract obtained from Verbascum nigrum aerial parts (VNE) and its six fractions (VNF1-VNF6) were initially screened regarding their effects on the viability of immortalized HaCaT keratinocytes and A431 epidermoid carcinoma cells (MTT assay, 24 h). None of the tested samples affected the viability of HaCaT cells in a concentration range of 25-150 μg/mL. VNE and VNF4 exhibited significant cytotoxic effects in A431 cells, with IC50 values of 81.92 and 12.27 μg/mL, respectively; the selectivity index was higher than 10 for VNF4. The untargeted LC/HR-MS/MS metabolite profiling led to the tentative annotation of a total number of 23 compounds. Of these, VNE comprised mainly iridoid glycosides (harpagoside, laterioside, acylated aucubin derivatives), whereas VNF4 showed a high abundance of triterpene saponin glycosides (ilwensisaponins A and C, songarosaponins A and B), constituents known for their selective cytotoxic potential

Influence of the post-harvest storage time on the multi-biological potential, phenolic and pyrrolizidine alkaloid content of comfrey (Symphytum officinale L.) roots collected from different European regions

Comfrey (Symphytum officinale L.) roots are well-known bioactive ingredients included in various cosmeceutical and pharmaceutical preparations. In this study, the influence of the post-harvest storage on the chemico-biological potential of roots collected from different European regions and stored for up to six months was investigated. Total phenolic content (TPC) and total phenolic acid content (TPAC) were spectrophotometrically estimated, whereas the levels of individual phenolic and pyrrolizidine alkaloidal markers were determined by HPLC-DAD and HPLC-MS/MS, respectively. The changes in the biological potential was tracked via antioxidant (DPPH, ABTS, CUPRAC, and FRAP) and anti-enzymatic (cholinesterase, tyrosinase, glucosidase, and amylase) assays. TPC and TPAC varied from 6.48-16.57 mg GAE/g d.w. root and from 2.67-9.03 mg CAE/g, respectively. The concentration of the four phenolics (rosmarinic acid, globoidnan A, globoidnan B, rabdosiin) and six pyrrolizidine alkaloids generally showed maximum values at 1-3 months, after which their levels significantly decreased. With respect to the bioassays, the samples showed a wide range of antioxidant and anti-enzymatic effects; however, a direct storage time-bioactivity relationship was not observed. Similar conclusions were also revealed by the multivariate and correlation analyses. Our study could improve the current knowledge of the shelf-life properties of comfrey-based products and enhance their industrial exploitation

Using the plants of Brazilian Cerrado for wound healing : from traditional use to scientific approach

Ethnopharmacological relevance The Brazilian Cerrado is a biome with a remarkable diversity of plant species, many of which are used mainly by local communities as a source of treatment to several pathologic processes, especially for the treatment of wounds. However, no systematic review exists focusing on the plants used in this respect and on the appropriate pharmacological investigations that substantiate the actions that are reported. This study revisits the traditional use of medicinal plants from the Brazilian Cerrado in the treatment of wounds and the pharmacological characteristics of the reported plant species. Methodology For the present article, previous studies on plants of the Brazilian Cerrado used for wound healing carried out between 1996 and 2018 were researched on various academic databases (PubMed, Elsevier, Springer, Lilacs, Google Escolar, and Scielo). Results A total of 33 studies were carried out on 29 plant species distributed into 18 families, mainly Fabaceae or Leguminosae (9), Bignoniaceae (2), Asteraceae (2), Euphorbiaceae (2). Considering the great diversity of Cerrado plants, only a small number of wound healing studies were carried out between 1996 and 2018. It was observed that there is a large gap between experimentation assay and traditional use. There are only few connections between the form of use by the population and the experiments conducted in the laboratory. We found that only about 12% of these studies considered to use the methodologies, or at least in parts, to obtain extracts such as those used in folk medicine. Approximately 37% of the experiments were performed using the bark as well as the same ratio for leaves, 6% using the fruits, and 9% using the seeds, roots or flowers. In several studies, there are reports of chemical constituents such as flavonoids and tannins, followed by steroid terpenes, saponins, and fatty acids, and alkaloids. However, approximately 35% of the studies did not supply information about compounds present in the preparation or the effect which could be attributed to these agents in respect to wound healing. Regarding treatment, most of the studies employed a topical treatment, though intraperitoneal and oral treatment were also described using either topical, oil-based formulations, but also gel- or saline-based formulations. Conclusions Although, there has been an increase in knowledge about the biological actions of plants from Cerrado biome, the scientific basis for the traditional use of these local medicinal plants in wound healing does not provide sufficient information on the efficacy of the treatment, the molecular mechanisms, or, in particular, the effective doses used and the drug interactions. Thus, focused research investigating these hypotheses from traditional knowledge is necessary to prove the evidence of the potential pharmacological action