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Elemental composition of Gossypium hirsutum L. (cotton), Oryza sativa L. (Asian rice), Phaseolus vulgaris L. (common bean), Saccharum spp. L. (sugarcane), and Zea mays L. (corn) was used to calculate their empirical formulas (unit carbon formulas) and growth stoichiometry. The empirical formulas were used to find standard enthalpy of formation, standard molar entropy, standard Gibbs energy of formation, and standard molar heat capacity. A comparison was made between thermodynamic properties of live matter of the analyzed plants and other unicellular and multicellular organisms. Moreover, the growth process was analyzed through standard enthalpy, entropy, and Gibbs energy of biosynthesis. The average standard Gibbs energy of biosynthesis was found to be +463.0 kJ/C-mol. Thus, photosynthesis provides energy and carbon for plant growth. The average intercepted photosynthetic energy was found to be 15.5 MJ/C-mol for the analyzed plants. However, due to inefficiency, a great fraction of the intercepted photosynthetic energy cannot be used by plants. The average usable photosynthetic energy was found to be –2.3 MJ/C-mol. The average thermodynamic driving force for growth is –1.9 MJ/C-mol. Driving forces of growth of C3 and C4 plants were compared. It was found that C4 plants have a greater driving force of growth than C3 plants, which reflects the greater efficiency of C4 photosynthesis. The relationship between the driving force and growth rates was analyzed by determining phenomenological L coefficients. The determined phenomenological coefficients span two orders of magnitude, depending on plant species and environmental conditions. The L coefficient of P. vulgaris was found to be lower than that of other plants, due to additional energy requirements of nitrogen fixation.

Biological, physical and chemical interaction between one (or more) microorganisms and a host organism, causing host cell damage, represents an infection. Infection of a plant, animal or microorganism with a virus can prevent infection with another virus. This phenomenon is known as viral interference. Viral interference is shown to result from two types of interactions, one taking place at the cell surface and the other intracellularly. Various viruses use different receptors to enter the same host cell, but various strains of one virus use the same receptor. The rate of virus–receptor binding can vary between different viruses attacking the same host, allowing interference or coinfection. The outcome of the virus–virus–host competition is determined by the Gibbs energies of binding and growth of the competing viruses and host. The virus with a more negative Gibbs energy of binding to the host cell receptor will enter the host first, while the virus characterized by a more negative Gibbs energy of growth will overtake the host metabolic machine and dominate. Once in the host cell, the multiplication machinery is shared by the competing viruses. Their potential to utilize it depends on the Gibbs energy of growth. Thus, the virus with a more negative Gibbs energy of growth will dominate. Therefore, the outcome can be interference or coinfection, depending on both the attachment kinetics (susceptibility) and the intracellular multiplication machinery (permittivity). The ratios of the Gibbs energies of binding and growth of the competing viruses determine the outcome of the competition. Based on this, a predictive model of virus–virus competition is proposed.

Es wird die Desolventierung von Polymerlösungen als Zwischenprodukte eines lösemittelbasierten Kunststoff-Recyclingprozesses behandelt. Es werden vier Polymer-Lösemittel-Systeme mit Polystyrol (PS) und Polyethylen (PE) in zwei Versuchsständen untersucht. Die Desolventierung von niedrigviskosen Lösungen erfolgt mithilfe der Vakuum-Entspannungs-Verdampfung. Die Entgasung von höherviskosen Polymerschmelzen wird in einem gerührten Vakuumtrockner durchgeführt. Massen-, Energie- und Kostenbilanzen der Prozesse ermöglichen die Identifizierung der Haupt-Einflussgrößen und die entscheidenden Parameter zur Vorhersage der Desolventierung sowie deren technischen und ökonomischen Umsetzung., This work focuses on the desolventization of polymer solutions as intermediates of a solvent-based recycling process of thermoplastics. Four polymer-solvent systems comprising polystyrene (PS) and polyethylene (PE) are investigated in two experimental setups. Low-viscos solutions are introduced to a vacuum flash evaporation. The degassing of higher-viscous polymer melts is performed by means of a stirred vacuum dryer. The mass, energy, and cost balances of the processes enable the identification of the primary influencing drivers and decisive parameters to predict the desolventization as well as its technical and economic implementation.

In a contribution to the improvement of model-based separation method development in liquid-liquid chromatography (LLC), factors influencing the separation performance, such as the column design, operating conditions and the biphasic solvent system, are systematically investigated. In addition, LLC is explored for the selective enrichment and purification of minor compounds from complex natural mixtures, using the bioactive hop compound xanthohumol C as an example., Grundlegende Einflussfaktoren wie Säulengeometrie, Betriebsbedingungen, und zweiphasige Lösungsmittelsysteme werden hinsichtlich ihrer Auswirkung auf die Trennleistung in der Flüssig-Flüssig Chromatographie (FFC) systematisch untersucht. Die Ergebnisse tragen zur Verbesserung einer modellbasierten Auslegung von FFC-Trennungen von Naturstoffen aus komplexen Mischungen bei. Darüber hinaus wird die FFC für eine selektive Anreicherung und Aufreinigung von Minorkomponenten aus komplexen Naturstoffmischungen am Beispiel der bioaktiven Hopfenkomponente Xanthohumol C untersucht.

Centrifugal partition chromatography uses the two liquid phases of a biphasic solvent system as stationary and mobile phases for a chromatographic separation. It is applied for the purification of natural compounds. The selection of biphasic systems for the separation of very hydrophilic or hydrophobic substances is challenging. This work focuses on alternative biphasic systems containing deep eutectic solvents that can be employed for the separation of hydrophobic substances, and ionic liquids, that are used with biomolecules, such as proteins., Zentrifugale Verteilungschromatographie nutzt ein zweiphasiges Lösungsmittelsystem als stationäre und mobile Phasen für eine chromatographische Trennung. Ein häufiges Einsatzgebiet ist die Aufreinigung von Naturstoffen. Lösungsmittelsysteme für die Trennung sehr hydrophiler oder hydrophober Substanzen zu finden, stellt eine Herausforderung dar. In dieser Arbeit wurden zweiphasige Systeme mit eutektischen Lösungsmitteln für die Trennung hydrophober Substanzen, und mit ionischen Flüssigkeiten für die Aufreinigung von Proteinen, untersucht.

Introduction: Symphytum officinale L. (comfrey, Boraginaceae) is a cultivated or spontaneously growing medicinal plant that is traditionally used for the treatment of bone fractures, hematomas, muscle pains and joint pains. A wide range of topical preparations and dried roots for ex tempore applications are marketed in European drug stores or pharmacies. Objective: The aim of this study was to perform the qualitative and quantitative analysis of pyrrolizidine alkaloids (PAs) and phenolic compounds in the hydroethanolic extracts of 16 commercial comfrey root batches purchased from 12 different European countries. Methods: Liquid chromatography hyphenated with high-resolution tandem mass spectrometry (LC-HRMS/MS) was used for the profiling of PAs and phenolic compounds, whereas LC-MS/MS and liquid chromatography with diode array detection (LC-DAD) were used for their quantification. Results: 20 PAs (i.e. intermedine, lycopsamine, acetylintermedine, acetyllycopsamine, symphytine, symphytine-N-oxide), 17 phenolic compounds (i.e. caffeic and rosmarinic acids, rabdosiin, globoidnan A, globoidnan B) and 9 nonphenolic compounds (sugars, organic and fatty acids) were fully or partly annotated in the analysed samples. In addition, the quantitative analyses revealed that globoidnan B, rabdosiin and globoidnan A are new phenolic markers that can be used together with rosmarinic acid and PAs for the quality control of commercial comfrey root batches. Conclusions: This study brings new insights into the phytochemical complexity of S. officinale, revealing not only numerous toxic PAs, but also a significant number of valuable phenolic compounds that could contribute to the bioactivities of comfreybased preparations

After adsorption and penetration, a virus hijacks a cell's metabolic machinery and uses it as a medium for its reproduction and growth through multiplication. Growth is competitive, since the same precursors and machinery are used by both the virus and its host cell. But what drives a virus to perform its life cycle more efficiently than its host? Gibbs energy represents the driving force for all chemical reactions in nature. Therefore, hypothetically Gibbs energy of growth can represent the driving force of viral lytic cycle. After chemical characterization of 17 viruses and their hosts, in this paper, growth reactions were suggested, and enthalpy, entropy and Gibbs free energy of both formation and growth were calculated. By comparing the Gibbs energy of growth of viruses and their hosts, it has been found that a virus always has a more negative Gibbs free energy of growth than its host implying that synthesis of viral components is more thermodynamically favorable. Thus, it seems that the physical laws explain observed biological phenomena - the hijack of host life machinery and high efficiency of virus growth.

This paper reports empirical formulas, enthalpies of formation, molar entropies, Gibbs energies of formation, and molar heat capacities at 25°C and 37°C for human soft tissues. The results show that Gibbs energy, except for certain tissues (adipose), is relatively low compared with the constituent elements, the average value being –17.57 kJ/C-mol. The average constant pressure heat capacity of hydrated human body soft tissues is 3.24 J/gK in agreement with other data in the literature.

Egg white is a raw material that consists of many bio-functional proteins. Their fractionation by classical chromatographic processes is impaired by the structural properties of egg white. Thus, egg white characteristics need to be modified prior to chromatographic fractionation. Mechanical devices offer a suitable method for this purpose. The subsequent fractionation was carried out with membrane based ion exchange chromatography, in lab scale as well as in pilot scale., Eiklar beinhaltet viele bio-funktionelle Proteine. Allerdings ist deren Fraktionierbarkeit mit Hilfe von klassischen Chromatographieverfahren durch die strukturellen Eigenschaften des Eiklars limitiert. Folglich müssen die Eiklarcharakteristika vor einer chromatographischen Fraktionierung modifiziert werden. Mechanische Methoden bieten hierfür eine adäquate Lösung. Die nachfolgende Fraktionierung wurde sowohl im Labor- als auch im Pilotmaßstab mittels einer membranbasierten Ionenaustauschchromatographie durchgeführt.

Egg white is a raw material that consists of many bio-functional proteins. Their fractionation by classical chromatographic processes is impaired by the structural properties of egg white. Thus, egg white characteristics need to be modified prior to chromatographic fractionation. Mechanical devices offer a suitable method for this purpose. The subsequent fractionation was carried out with membrane based ion exchange chromatography, in lab scale as well as in pilot scale., Eiklar beinhaltet viele bio-funktionelle Proteine. Allerdings ist deren Fraktionierbarkeit mit Hilfe von klassischen Chromatographieverfahren durch die strukturellen Eigenschaften des Eiklars limitiert. Folglich müssen die Eiklarcharakteristika vor einer chromatographischen Fraktionierung modifiziert werden. Mechanische Methoden bieten hierfür eine adäquate Lösung. Die nachfolgende Fraktionierung wurde sowohl im Labor- als auch im Pilotmaßstab mittels einer membranbasierten Ionenaustauschchromatographie durchgeführt.

The structure of deposit layers formed by biopolymers during membrane separation processes has a strong impact on the degree of mass transfer. In order to develop measures for the reduction of the deposit layer formation, the molecular structure formation mechanism was elucidated. For both micro- and ultrafiltration of the substrates milk and whey, specific molecular mechanisms of deposit formation were identified. Based on this, it was possible to derive measures for the minimization of deposit layer formation., Die Struktur der während Membranfiltrationen aus Biopolymeren gebildeten Deckschichten hat einen entscheidenden Einfluss auf die Güte des Stofftransports. Um Maßnahmen zur Minimierung der Deckschichtbildung ableiten zu können, wurde der molekulare Strukturbildungsmechanismus aufgeklärt. Dieser wurde substratspezifisch für die Mikro- und Ultrafiltration von Milch und Molke identifiziert und daraus geeignete Maßnahmen zur Reduktion der Deckschichtbildung abgeleitet.

Mit COSMO-RS können thermophysikalische Stoffdaten für die Prozesssimulation und Prozesstechnik auf Basis der Molekülstruktur berechnet werden. In dieser Arbeit wird die Erweiterung COSMO-RS-DARE für die Berücksichtigung der Dimerisierung mit COSMO-RS evaluiert. Außerdem wird eine Gruppenbeitragsmethode für COSMO-RS zur Berechnung von physikalischen Gaslöslichkeiten entwickelt. Des Weiteren wird die Berechnung von Fickschen Diffusionskoeffizienten aus Randdiffusionskoeffizienten mit COSMO-RS untersucht., With COSMO-RS thermophysical properties for process simulation and process engineering can be calculated based on molecular structure. In this thesis, the extension COSMO-RS-DARE for consideration of dimerization with COSMO-RS is evaluated. Furthermore, a group contribution method for COSMO-RS for calculating physical gas solubilities is developed. In addition, calculation of Fick diffusivities with diffusivities at infinite dilution with COSMO-RS is investigated.

The flow inside a chromatographic column depends decisively on the packed bed inside. Non‐destructive X‐ray computed tomography (CT) was applied as a novel measurement technique to visualize the distribution of velocity and axial dispersion coefficients in preparative scale columns. The results show, that spherical particles seem to be more efficient than irregular ones in terms of HETP, which has to be partly a result of the more homogeneous flow profile they induce. The prediction of column performance in dependence of the structure of the packed bed was simulated by CFD (Computational Fluid Dynamics), using a model which besides the hydrodynamics parameters attained by CT also includes adsorption isotherms and mass transfer parameters. The results of the CFD simulation shall help to establish rules for selecting the right adsorption material for a given separation task in advance.