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In recent years, the alginate-encapsulated in vitro-derived shoot tips and nodal segments have been employed as an alternative to somatic embryos method of artificial seed production. Encapsulation of non-embryogenic propagules offers an efficient technique for clonal propagation of elite genotypes e.g. plants of medicinal importance and also enables the establishment of basal collection for gene banks. The artificial seeds technology based on vegetative micropropagules may be useful not only in large-scale propagation but also in short- and long-term conservation and germplasm exchange of desirable species genotypes. This paper presents a brief overview of current status of plants of medicinal value propagated by alginate-encapsulated non-embryogenic plant material.
Eryngium planum L. cell and organ cultures were maintained on Murashige and Skoog media (MS), supplemented with exogenous hormones of different types and various concentrations for high biomass growth. The callus and cell suspension cultures were treated with increased sucrose concentration and/or elicited by methyl jasmonate for the enhancement of selected phenolic acids accumulation. Three phenolic acids, rosmarinic acid (RA), chlorogenic acid (CGA) and caffeic acid (CA), were detected by HPLC-DAD in those cultures. The sum of their content in the dry material was found to be higher in the shoot culture (3.95 mg g⁻¹), root culture (7.05 mg g⁻¹), callus (6.20 mg g⁻¹) and cell suspension (2.04 mg g⁻¹) than in the leaves (1.87 mg g⁻¹) and roots (0.76 mg g⁻¹) of intact plants. The major compound of in vitro cultures was always rosmarinic acid. The content of RA could be increased approximately threefold (16.24 mg g⁻¹) in the callus culture and approximately twofold (3.91 mg g⁻¹) in the cell suspension culture by elicitation with 100 µM methyl jasmonate (MeJA). The higher concentration of sucrose (S) in the medium (5, 6 %) led to over a twofold increase of CGA content in the callus culture (2.54 mg g⁻¹). The three mentioned phenolic acids have been found in E. planum undifferentiated and differentiated in vitro cultures for the first time.
The antimicrobial activity of ethanolic extracts from leaves and roots of three Eryngium L. genera (E. planum, E. campestre, E. maritimum) native to Poland was tested by the method of series dilutions against different Gram-positive bacteria (two strains) and fungi (five species). The extracts were analyzed by TLC method to confirm phenolic acids, triterpenoid saponins, flavonoids and acetylenes presence. The antimicrobial activity of extracts compared with the reference substance were expressed by Minimal Inhibitory Concentration (MI C). The results have shown that the ethanolic extracts inhibit the growth of Staphylococcus aureus and all tested fungi.
Introduction: Callus and cell suspension cultures are widely applied in investigation of production of highvalue secondary metabolites, which may be used as cosmeceuticals, nutraceuticals and pharmaceuticals. Plant cell cultures are promising alternative to intact plant sources for the production of plant-derived drugs of industrial importance. Objective: The aim of the study was to (i) initiate the cell suspension culture of Chaenomeles japonica from homogenous and uniform callus, (ii) stabilize the selected line and (iii) verify its ability to produce the desired groups of secondary metabolites – pentacyclic triterpenoids and polyphenols. Methods: To establish a cell suspension culture, stabilized and homogeneous callus was selected. Cell cultures were systematically passaged every 2 weeks to fresh liquid medium with the same composition. Biomass from cultures at the growth phase and stationary phase was designated for phytochemical research. UHPLC-DAD-MS analyzes were performed. At the same time, their macroscopic and microscopic observations were carried out. Results: Cells of suspension culture line A2 were characterized by the intense divisions. Cell culture extracts (both from the growth phase and stationary phase) contained pentacyclic triterpenoids. In addition, phenolic compounds (chlorogenic acid and proanthocyanidins type B) and in a small amount also epicatechin are present in the extract of the cells harvested from the growth phase. In the present studies, three pentacyclic triterpenoids were detected and quantified in the extracts of cell suspensions and callus line A2. Ursolic and oleanolic acids were the main triterpenoids in the studied extracts. The cell suspension culture from the growth phase exhibited the highest content of ursolic, oleanolic, and betulinic acid (separately and together). Conclusion: The cell suspension culture of Chaenomeles japonica is a promising source of pentacyclic triterpenoids.
Introduction: Due to increasing resistance against antibiotics and antifungal agents, crude plant extracts, fractions, and isolated pure compounds became a new interest as antimicrobial agents. Objectives: The antimicrobial activity of methanolic extracts and fractions of Eryngium planum L., E. campestre L., and E. maritimum L. was evaluated against selected bacteria, yeast and mould, and compared in tested Eryngium species and in their organs. Methods: The antimicrobial activity was studied with use of broth microdilution method. The antibacterial (Staphylococcus aureus, Pseudomonas aeruginosa) and antifungal (Candida albicans, Aspergillus niger) activity of selected extracts and fractions compared with the reference substance was expressed by Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal/Fungicidal Concentration (MBC/MFC).The extract and fraction compounds were identified on the basis of TLC examination. Results: The saponin-phenolic acid fractions of E. maritimum and E. planum and a saponin fraction of E. planum showed the highest activity against S. aureus (MIC = 1–2.5 mg·ml-1). The growth of C. albicans was inhibited by methanolic extract of E. planum cell suspension culture (MIC = 7.8 mg·ml-1). Conclusion: The antimicrobial activity depends on the Eryngium species, tested biomass, and microorganism.
An efficient micropropagation protocol for production of genetically uniform clones of Eryngium campestre L. was developed. To determine the effect of nutritional and hormonal factors on shoot and root development and bioactive compounds production, three variants of media differing in the content of macro- and micronutrients, as well as plant growth regulators of various types and concentrations were tested. The highest regeneration (100%), with over 13 shoots per explant, was induced on Murashige and Skoog (MS) medium with 1.0 mg lˉ¹ benzyladenine (BA) and 0.1 mg lˉ¹ indole-3-acetic acid (IAA). The in vitro derived shoots multiplied through axillary bud formation were rooted and transferred to an experimental plot with 78% frequency of survival. Flow cytometry showed no variation in nuclear DNA between the seedlings and micropropagated plants. Preliminary thin layer chromatography (TLC) analysis indicated that phenolic acids, saponins, flavonoids and acetylenes were present in plant biomass. Ultra high performance liquid chromatography (UHPLC) analysis revealed that shoots and roots from in vitro derived plants and root cultures maintained the ability to produce rosmarinic acid (RA), rosmarinic acid hexoside (RA-HEX) and chlorogenic acid (CGA). The highest phenolic acid content was detected in roots of in vitro regenerated plants. The extract from those roots expressed the highest inhibitory effect against bacteria Staphylococcus aureus, as well as dermatophytes Trichophyton mentagrophytes and T. rubrum.
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