DOI: 10.1002/elsc.202000078
The cover picture shows a process of submerged cultivation of hairy root culture of red beet in a stirred tank bioreactor, different types Beta vulgaris L. in vitro ...cultures and their ploidity levels. Biosynthesis of red betacyanins and yellow betaxanthins, used as food colorants and antioxidant additives, was found to be related with the level of differentiation of developed in vitro systems and underwent cycles of endoreduplication. Among the investigated red beet in vitro cultures, hairy roots showed the best potential for production of betalains. For details see article DOI 10.1002/elsc.202000078 on page 68.
Three often cited systems for the extraction of plant nuclei for flow cytometric measurement (CyStain PI, Partec GmbH, Münster, Germany, the method of Arumuganathan and Earle, and LB01 buffer) ...failed, when applied to the hairy roots of red beet (
Beta vulgaris). By combining these systems and introducing a centrifugation step, the extraction, staining, and analysis of nuclei from this tissue were performed successfully.
The common effect of NO₃ ⁻, KH₂PO₄ and sucrose on the biosynthesis of hyoscyamine by diploid and tetraploid Datura stramonium L. hairy root cultures were studied. Polynominal regression models were ...elaborated for the description of hyoscyamine biosynthesis as a consequence of variation of the investigated variables (NO₃ ⁻ between 31 and 47 mM, and sucrose between 20.00 and 40.00 g/l for diploid and NO₃ ⁻ between 31 and 47 mM; KH₂PO₄ between 0.50 and 1.25 mM, and sucrose between 50 and 70 g/l, for tetraploid hairy roots, respectively). Optimization procedures allowed us to establish the optimal concentrations of the investigated variables and to propose the modified MS nutrient media, with 1.10 g/l KNO₃, 0.17 g/l KH₂PO₄, and 40 g/l sucrose, for diploid and with 1.10 g/l KNO₃, 0.17 g/l KH₂PO₄, and 50 g/l sucrose, for tetraploid Datura stramonium L. hairy root cultures. The proposed modified MS media provided optimal hyoscyamine production yield for both investigated hairy root cultures.
We previously speculated that the synergistically enhanced antimicrobial activity of Magainin 2 and PGLa is related to membrane adhesion, fusion, and further membrane remodeling. Here we combined ...computer simulations with time-resolved in vitro fluorescence microscopy, cryoelectron microscopy, and small-angle X-ray scattering to interrogate such morphological and topological changes of vesicles at nanoscopic and microscopic length scales in real time. Coarse-grained simulations revealed formation of an elongated and bent fusion zone between vesicles in the presence of equimolar peptide mixtures. Vesicle adhesion and fusion were observed to occur within a few seconds by cryoelectron microscopy and corroborated by small-angle X-ray scattering measurements. The latter experiments indicated continued and time-extended structural remodeling for individual peptides or chemically linked peptide heterodimers but with different kinetics. Fluorescence microscopy further captured peptide-dependent adhesion, fusion, and occasional bursting of giant unilamellar vesicles a few seconds after peptide addition. The synergistic interactions between the peptides shorten the time response of vesicles and enhance membrane fusogenic and disruption properties of the equimolar mixture compared with the individual peptides.
Two‐phase bioreactor cultivation system was developed and applied for in sito recovery of extracellular galanthamine during the cultivation of Leucojum aestivum L. shoot culture in a modified column ...bioreactor system. The inclusion of an external circulation column with adsorbent resin Amberlite XAD‐4 as a second phase, on the 21st day of the beginning of cultivation resulted in 1.25 folds increase in biomass accumulation and maximal amounts of accumulated galanthamine of 6 mg/L (3.1 mg/L intracellular and 2.9 mg/L extracellular). It was demonstrated that the inclusion of a second phase at the cultivation of the L. aestivum shoot culture in a bubble column bioreactor with internal sections redirected the alkaloid metabolism to galanthamine synthesis and inhibits the synthesis of hemanthamine and lycorine type alkaloids. Our research demonstrated that the application of the two‐phase cultivation systems could be an important tool to increase the yields of valuable secondary metabolites in plant tissue culture‐based bioprocess.
Plant cells contain a wide range of interesting secondary metabolites, which are used as natural pigments and flavoring agents in foods and cosmetics as well as phyto‐pharmaceutical products. ...However, conventional industrial extraction from whole plants or parts of them is limited due to environmental and geographical issues. The production of secondary metabolites from in vitro cultures can be considered as alternative to classical technologies and allows a year‐round cultivation in the bioreactor under optimal conditions with constant high‐level quality and quantity. Compared to plant cell suspensions, differentiated plant in vitro systems offer the advantage that they are genetically stable. Moreover, the separation of the biomass from culture medium after fermentation is much easier. Nevertheless, several investigations in the literature described that differentiated plant in vitro systems are instable concerning the yield of the target metabolites, especially in submerged cultivations. Other major problems are associated with the challenges of cultivation conditions and bioreactor design as well as upscaling of the process. This article reviews bioreactor designs for cultivation of differentiated plant in vitro systems, secondary metabolite production in different bioreactor systems as well as aspects of process control, management, and modeling and gives perspectives for future cultivation methods.
Betalains biosynthesis and antiradical scavenging activity were investigated during cultivation of four hairy root cultures of Beta vulgaris, obtained from different cultivars (Bordo, Egyptian, ...Detroit 2 and Detroit Dark Red). The best producer of betalains was a hairy root culture from Beta vulgaris cv. Detroit Dark Red (13.27 mg/g dry weight total pigment production). The ethanol extract, derived from roots of the same culture grown for 15 days under submerged conditions, showed a high antiradical activity (83% of inhibition of the stable DPPH.).
Satureja montana L. is used as a traditional culinary spice in the Balkan Peninsula cuisine, as well as in the folk and traditional medicine for treatment of different diseases. The supply of ...secondary metabolites from naturally growing plants has many restrictions, such as biomass availability and variations in the chemical composition, which is most strongly affected by seasonal and environmental- mental factors. These disadvantages could be overcome by cultivating plants in optimized and controlled in vitro conditions. The purpose of the current study was to compare the phytochemical compositions of newly developed in vitro plants and intact plants of S. montana used for production of secondary metabolites. The GC-MS analysis revealed the presence of a number of primary (carbohydrates, amino acids, organic acids and lipids) and secondary metabolites (phenolic acids) with pharmacological and biological activities beneficial to humans. The results revealed that in vitro S. montana plants are a poten- tial biotechnological matrix for the production of valuable biologically active substances for the food, pharmaceutical and cosmetic industries.
Recent designs have allowed hollow cathode gas plasma sources to be adopted for use in plasma-enhanced atomic layer deposition with the benefit of lower oxygen contamination for non-oxide films (a ...brief review of this is provided). From a design perspective, the cathode metal is of particular interest since—for a given set of conditions—the metal work function should determine the density of electron emission that drives the hollow cathode effect. However, we found that relatively rapid surface modification of the metal cathodes in the first hour or more of operation has a stronger influence. Langmuir probe measurements and hollow cathode electrical characteristics were used to study nitrogen and oxygen plasma surface modification of aluminum and stainless-steel hollow cathodes. It was found that the nitridation and oxidation of these metal cathodes resulted in higher plasma densities, in some cases by more than an order of magnitude, and a wider range of pressure operation. Moreover, it was initially thought that the use of aluminum cathodes would not be practical for gas plasma applications, as aluminum is extremely soft and susceptible to sputtering; however, it was found that oxide and nitride modification of the surface could protect the cathodes from such problems, possibly making them viable.
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