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Although the handling and exploitation of cyanobacteria is associated with some challenges, these phototrophic bacteria offer great opportunities for innovative biotechnological processes. This chapter covers versatile aspects of working with cyanobacteria, starting with up-to-date in silico and in vitro screening methods for bioactive substances. Subsequently, common conservation techniques and vitality/viability estimation methods are compared and supplemented by own data regarding the non-invasive vitality evaluation via pulse amplitude modulated fluorometry. Moreover, novel findings about the influence the state of the pre-cultures have on main cultures are presented. The following sub-chapters deal with different photobioreactor-designs, with special regard to biofilm photobioreactors, as well as with heterotrophic and mixotrophic cultivation modes. The latter topic provides information from literature on successfully enhanced cyanobacterial production processes, augmented by own data.

With regard to the emerging health threat by antibiotic resistant bacteria, bacteriocins are considered as a promising way to overcome this urgent problem. In this work, a hitherto unknown bacteriocin from the terrestrial cyanobacterium Chroococcidiopsis cubana was heterologously expressed in Escherichia coli, purified to homogeneity and tested for activity against several bacteria and one yeast species. The compound showed potent bacteriolytic activity against several Gram-positive bacteria and slight activity against one Gram-negative strain. The bacteriocin had no cytotoxic impact on mouse neuroblastoma N2a cells, indicating its potential for treatment against Gram-positive bacterial pathogens in human diseases.

Cyanobacteria represent a large group of bacteria with underestimated scientific potential. Recent studies indicate them as a great reservoir of secondary metabolites with antifungal, antiviral or antibacterial activity. However, common, well established research techniques cannot be easily adapted to these organisms. Slow growth rates and irregular cell aggregates constitute challenges for researchers dealing with cyanobacteria. In this work, we present an innovative new method enabling a quick, easy and economical vitality determination of cyanobacterial strains, as, e.g. required for the finding of optimal cryopreservation conditions. We were able to measure the vitality of previously cryopreserved and defrosted Trichocoleus sociatus samples within 45 min by means of their O2‐production. For each run, a cell wet mass of only 0.5 g was required. By application of this method, we could find DMSO (5% v/v) and glycerin (15% v/v) to be the most promising cryoprotectants for the conservation of T. sociatus cells. DMSO and glycerin guaranteed a vitality rate of 80–90% and 60–70% after up to four weeks of cryopreservation, compared to fresh cell material.

The cultivation of cyanobacteria with the addition of an organic carbon source (meaning as heterotrophic or mixotrophic cultivation) is a promising technique to increase their slow growth rate. However, most cyanobacteria cultures are infected by non-separable heterotrophic bacteria. While their contribution to the biomass is rather insignificant in a phototrophic cultivation, problems may arise in heterotrophic and mixotrophic mode. Heterotrophic bacteria can potentially utilize carbohydrates quickly, thus preventing any benefit for the cyanobacteria. In order to estimate the advantage of the supplementation of a carbon source, it is essential to quantify the proportion of cyanobacteria and heterotrophic bacteria in the resulting biomass. In this work, the use of quantitative polymerase chain reaction (qPCR) is proposed. To prepare the samples, a DNA extraction method for cyanobacteria was improved to provide reproducible and robust results for the group of terrestrial cyanobacteria. Two pairs of primers were used, which bind either to the 16S rRNA gene of all cyanobacteria or all bacteria including cyanobacteria. This allows a determination of the proportion of cyanobacteria in the biomass. The method was established with the two terrestrial cyanobacteria Trichocoleus sociatus SAG 26.92 and Nostoc muscorum SAG B-1453-12a. As proof of concept, a heterotrophic cultivation with T. sociatus with glucose was performed. After 2 days of cultivation, a reduction of the biomass partition of the cyanobacterium to 90% was detected. Afterwards, the proportion increased again.

The cyanobacterium Nostoc sp. BB 92.3. had shown antibacterial activity. A cultivation as biofilm, a self-forming matrix of cells and extracellular polymeric substances, increased the antibacterial effect. A new photobioreactor system was developed that allows a surface-associated cultivation of Nostoc sp. as biofilm. High-density polyethylene carriers operated as a moving bed were selected as surface for biomass immobilization. This system, well established in heterotrophic wastewater treatment, was for the first time used for phototrophic biofilms. The aim was a cultivation on a large scale without inhibiting growth while maximizing immobilization. Cultivation in a small photobioreactor (1.5 L) with different volumetric filling degrees of carriers (13.4%-53.8%) in a batch process achieved immobilization rates of 70%-85% and growth was similar to a no-carrier-control. In a larger photobioreactor (65 L) essentially all of the biomass was immobilized on the carriers and the space-time yield of biomass (0.018 g

Cyanobacteria developed an enormous reservoir of bioactive secondary metabolites in order to prevail against competitive microorganisms and harsh environmental impacts. Many cyanobacterial substances with vast economical, medical and biotechnological potential have been described in the past. However, most of the examined bacteria are aquatic strains. We want to take a closer look on their terrestrial relatives which also possess a rich secondary metabolome that is still to explore.

Induction of an axenic filamentous-like callus growth from the brown algae Fucus vesiculosus is described. Different treatments were investigated in various combinations to develop axenic cultures based on identification of surface symbionts via 18S ribosomal RNA. Moreover, viability was confirmed after such processes by 2,3,5-triphenyl tetrazolium chloride assay that demonstrated an average viability of 29%, relative to nonsterilized explants. After six weeks of a phototrophic cultivation on artificial sea water-12-nitrilotriacetic acid (0.5% w/v agar), a filamentous-like callus growth was observed, which was identified genetically through its mitochondrial DNA after subculturing. Achievement of confirmed marine callus cultures might enrich old previously established blue biotechnology techniques and open new chances for cultivation of brown algae for production of good manufacturing practice-compliant bioproducts.

Phototrophic biofilms, in particular terrestrial cyanobacteria, offer a variety of biotechnologically interesting products such as natural dyes, antibiotics or dietary supplements. However, phototrophic biofilms are difficult to cultivate in submerged bioreactors. A new generation of biofilm photobioreactors imitates the natural habitat resulting in higher productivity. In this work, an aerosol-based photobioreactor is presented that was characterized for the cultivation of phototrophic biofilms. Experiments and simulation of aerosol distribution showed a uniform aerosol supply to biofilms. Compared to previous prototypes, the growth of the terrestrial cyanobacterium Nostoc sp. could be almost tripled. Different surfaces for biofilm growth were investigated regarding hydrophobicity, contact angle, light- and temperature distribution. Further, the results were successfully simulated. Finally, the growth of Nostoc sp. was investigated on different surfaces and the biofilm thickness was measured noninvasively using optical coherence tomography. It could be shown that the cultivation surface had no influence on biomass production, but did affect biofilm thickness.

Phototrophic biofilms produce a matrix of extracellular polymeric substances (EPS), which holds the cells together and functions inter alia as nutrient storage and protection layer. EPS mainly consist of water, polysaccharides, proteins, lipids and nucleic acids as well as lysis and hydrolysis products which makes the composition very complex. Thus, rough simplifications are used and commonly one or at most two components of the EPS are examined. In this work a new procedure for separation and analysis of EPS in the main components (i) polysaccharides, (ii) proteins and (iii) lipids is presented with recovery rates of nearly 100 %. The method was established with synthetic EPS, which based on the composition of real EPS described in literature. Afterwards, the method was transferred to real EPS samples allowing a deeper insight in the composition of EPS from only one sample. The composition of EPS-extracts from Nostoc spec, cultivated under heterotrophic and mixotrophic batch and fed-batch conditions, was analysed during a cultivation period of 14 days. It was observed that mixotrophic cultivation led to higher amounts of carbohydrates, lipids and proteins than heterotrophic cultivation respectively, regardless of batch or fed-batch culture. While the amount of proteins in the EPS increased during the cultivation period, carbohydrates and lipids were dominant in the beginning and decreased afterwards.

Chloroperoxidase (CPO) is a versatile enzyme, which is secreted by the marine fungus Caldariomyces fumago (Leptoxyphium fumago). However, the application of the enzyme is hampered by its high price, which is due to the costly, labor-intensive purification process. One challenge of the downstream process is the removal of a coproduced black pigment that forms a complex with the active enzyme. While strain development can be considered as an option to reduce the synthesis of the interfering pigment, the metabolism of the microorganism can be altered alternatively by using the biofilm growth mode of the fungus. The aim of this study was to reduce pigment formation during CPO synthesis. We investigated for the first time CPO production during C. fumago biofilm growth initiated through the presence of different microstructured stainless steel surfaces (material number: 1.4571; AISI 316Ti). CPO production by C. fumago was similar when grown as a biofilm or in suspension, whereas pigment formation was drastically reduced by cells grown on moderately structured surfaces (Ra = 0.13 ± 0.02 μm). The possibilities of biofilm growth for changing cell properties and for continuous fermentation are discussed.

Terrestrial cyanobacteria are a promising source for the production of biotechnological interesting metabolites. Some of these organisms of potential economic importance live in form of phototrophic biofilms and are therefore difficult to cultivate under laboratory conditions. However, there are some cultivation systems that mimic natural growth conditions, they are neither applicable for a scale-up, nor commercially available. Nevertheless, common cultivation systems like open ponds are designed for submerged conditions and an exchange against emerse photobioreactor systems (ePBRs) would be a cost-intensive procedure. Heterotrophic and mixotrophic cultivation could provide an alternative. In this work, cells of non-axenic mixed cultures of the terrestrial cyanobacteria Trichocoleus sociatus and Nostoc muscorum were cultivated for 14 days under phototrophic, heterotrophic and mixotrophic submerged conditions. The influence of different carbon sources, such as glucose, fructose, galactose, raffinose and potassium acetate, as well as the difference between batch and fed-batch cultivation on growth behaviour was analyzed. Mixotrophic cultivation led to higher cell concentrations as phototrophic and heterotrophic cultivation, regardless of which carbon source was used. A medium supplement of 2.53 g L−1 raffinose yielded a cell dry weight of 3.77 g L−1 for T. sociatus under mixotrophic fed-batch conditions, whereas for N. muscorum the mixotrophic fed-batch mode with glucose was the best option. It led to a dry weight of 2.46 g L−1 after 14 days of cultivation. It was observed that the two strains were able to use several carbohydrates as carbon sources and even much better than acetate. The composition of heterotrophic and mixotrophic non-axenic cultures was analyzed using qPCR during the whole cultivation period. Although there were differences in carbon utilization between the strains, the results indicate that in general terrestrial cyanobacteria are able to grow heterotrophically and that the increase in dry weight is not attributed to the growth of heterotrophic coexisting organisms.

A colorimetric sulpho-phospho-vanillin method was developed for the quantification of total lipids in small sample volumes. The developed method is easy to perform and can be used for high throughput analysis of lipid contents in 96-well microplates. In contrast to previous studies, solvents had a great influence on the surface of microplates. Different solvents were tested, but methanol was the only one, which did not show any impact on surface material. Therefore, it was used to dissolve the extracted lipids quantitatively, which were then transferred to the microplates for further processing. In this study, the method was used to quantify the total lipid amounts in extracts of extracellular polymeric substances (EPS) from terrestrial cyanobacteria. These extracellular lipids are of great interest, especially with regard to the production of antimicrobial substances. The two strains Trichocoleus sociatus and Nostoc muscorum were cultivated under heterotrophic conditions with glucose as additional carbon source. The lipid content of the two strains differed during the cultivation period. On average, the amount of lipids reached the highest value in the beginning of heterotrophic cultivation. Although the experiments were conducted under submerged conditions, cyanobacterial cells showed a surface-associated growth. The fluctuations in lipid content might express the different stages of biofilm formation.

Terrestrial cyanobacteria are phototrophic microorganisms, which grow embedded in a matrix of extracellular polymeric substances (EPS) as biofilms. To perform photosynthesis, cyanobacteria have developed, additionally to chlorophyll-a and carotenoids, the so-called phycobilisomes, which consist of differently pigmented phycobiliproteins (PBPs). The production of natural dyes, pharmaceutical substances and their nutrient rich biomass makes cyanobacterial biofilms interesting research targets for industrial development. However, characterization of biofilms during cultivation implies several difficulties, since standard sampling applied in suspended cultures is not possible. The aim of this study was to find new possibilities for documenting biofilm growth. Therefore, two methods for non-invasive examination of phototrophic biofilms were combined. The terrestrial cyanobacteria Trichocoleus sociatus und Coleofasciculus chthonoplastes were cultivated surface-associated in an aerosol. Every three to four days biofilm thickness was measured using optical coherence tomography (OCT) and biofilm area using PAM fluorometry. Additionally, three replicates were harvested to determine biomass formation and pigment composition. According to our results, an increase of biomass, biofilm thickness and biofilm area was detected. The non-linear correlation between these parameters indicates an increase of biofilm area and thickness in the early phase of cultivation with a time-delayed biomass production. Hereby, possibly the proportion of EPS and biomass changed in the beginning in combination with biofilm spreading to increase the utilization of available light and aerosol components. Afterwards, biomass production was increased. Concerning pigment composition in the course of cultivation, for T. sociatus all PBPs were degraded, whereas in C. chthonoplastes an increase of all PBPs was measured. This can be explained with the role of PBPs for photosynthesis but as well as nitrogen storage, which is adjusted strain dependent. Summarizing, the shown methods are suitable for phototrophic biofilm characterization in a small scale. This allows the examination of cyanobacteria and a valuation of their suitability for possible production processes.

The original version of this article unfortunately contains mistake introduced during the publishing process. The names of the authors were interchanged in the author group. The corrected author group is shown above.

Induction of an axenic filamentous‐like callus growth from the brown algae Fucus vesiculosus is described. Different treatments were investigated in various combinations to develop axenic cultures based on identification of surface symbionts via 18S ribosomal RNA. Moreover, viability was confirmed after such processes by 2,3,5‐triphenyl tetrazolium chloride assay that demonstrated an average viability of 29%, relative to nonsterilized explants. After six weeks of a phototrophic cultivation on artificial sea water‐12‐nitrilotriacetic acid (0.5% w/v agar), a filamentous‐like callus growth was observed, which was identified genetically through its mitochondrial DNA after subculturing. Achievement of confirmed marine callus cultures might enrich old previously established blue biotechnology techniques and open new chances for cultivation of brown algae for production of good manufacturing practice‐compliant bioproducts.

Isothermal microtitration calorimetry was performed to analyze the interaction of fucoidan and dextran sulfate with toluidine blue O (TB) to achieve relevant and characteristic thermodynamic information. Thermodynamic data obtained were referred to the anionic binding sites of the sulfated polysaccharides (SPS) and were not related to the polysaccharide concentration in general. Enthalpic values achieved by the two SPS titrations in TB solutions could be approximated using a single fit curve. The same also applies for the TB titrations in SPS solutions. Evaluation of the data obtained for forward and reverse titrations could not be performed since it results in inconsistent enthalpic and entropic contributions. An appropriate modeling could only be performed assuming two non-symmetric binding sites at the SPS although the thermodynamic data revealed a 1:1 stoichiometry. A 1:2 model accounts for the deviation generated by the stacking of the TB molecules. Data obtained for the binding of a single TB to a sulfate ester indicate highly negative values (−9.7 to −9.4 kcal mol−1) for the change in Gibbs energy and thus a spontaneous enthalpy-driven reaction. Formally, further thermodynamic values contain information about the second binding site at SPS. In this case, the information provided can be equated with the TB–TB interaction or dimerization that is entropically favored (T∆S = 13.7–16.5 kcal mol−1). Equilibrium constant for TB binding at the sulfate esters values to 0.7–1.4 10−7 mol−1, and TB–TB interaction has a binding constant of 2.1–3.0 10−4 mol−1, indicating an equilibrium which is mainly positioned at the dimers.

Fucoidan is a sulfated polysaccharide with promising pharmacological applications. Due to its medicinal properties, there is a demand for a separation technique that yields a high purification grade. Here, we present a novel purification tool for recovering fucoidan from the marine brown macroalgae Fucus vesiculosus. The developed method is based on amino‐derivatized Sepabeads® EC‐EA. The beads were modified with toluidine blue (TB), a thiazine derivative, to exploit the strong donor acceptor interactions between the cationic dye and the anionic polysaccharide. The adsorption kinetics and the binding capacity of the resin were analyzed. A Sips model was used to approximate the adsorption isotherm, resulting in a maximum capacity of 127.7 mg fucoidan per g adsorbent. Investigation of the effect of adsorption step's pH on purity and chemical structure was performed by TB and Fourier transform infra‐red spectroscopy assays. Results showed that adsorption at pH 1 and 6 had negligible effects on fucoidan's chemical structure. However, purity was actually improved by 1.55‐ and 1.69‐fold at pH 1 and 6, respectively, with an average yield of 5 g/100 g dried algae powder. In contrast, only a 1.46‐fold increment was observed in fucoidan purified by the traditional method at pH 2, with a yield of 7.5 g/100 g dried algae powder. Furthermore, fucoidan purified by this method at pH 6 complies with, or even exceeds the quality of the commercially available (≥95% pure) fucoidan (Sigma‐Aldrich®) with respect to molecular weight and sulfur content. Therefore, dye affinity chromatography provides more advantages than the classically used techniques for fucoidan purification.

Due to their anion exchange characteristics, layered double hydroxides (LDHs) are suitable for the detoxification of aqueous, fatty acid containing fermentation substrates. The aim of this study is to examine the adsorption mechanism, using crude glycerol from plant oil esterification as a model system. Changes in the intercalation structure in relation to the amount of fatty acids adsorbed are monitored by X-ray diffraction and infra-red spectroscopy. Additionally, calcination of LDH is investigated in order to increase the binding capacity for fatty acids. Our data propose that, at ambient temperature, fatty acids can be bound to the hydrotalcite by adsorption or in addition by intercalation, depending on fatty acid concentration. The adsorption of fatty acids from crude glycerol shows a BET-like behavior. Above a fatty acid concentration of 3.5 g L−1, intercalation of fatty acids can be shown by the appearance of an increased interlayer spacing. This observation suggests a two phase adsorption process. Calcination of LDHs allows increasing the binding capacity for fatty acids by more than six times, mainly by reduction of structural CO3 2−.

For several thousand years, biotechnology and its associated technical processes have had a great impact on the development of mankind. Based on empirical methods, in particular for the production of foodstuffs and daily commodities, these disciplines have become one of the most innovative future issues. Due to the increasing detailed understanding of cellular processes, production strains can now be optimized. In combination with modern bioprocesses, a variety of bulk and fine chemicals as well as pharmaceuticals can be produced efficiently. In this article, some of the current trends in biotechnology are discussed.

BACKGROUND Currently, several techniques exist for the downstream processing of protein, phytic acid and sinapic acid from rapeseed and rapeseed meal, but no technique has been developed to separate all of the components in one process. In this work, two new downstream processing strategies focusing on recovering sinapic acid, phytic acid and protein from rapeseed meal were established. RESULTS The sinapic acid content was enhanced by a factor of 4.5 with one method and 5.1 with the other. The isolation of sinapic acid was accomplished using a zeolite-based adsorbent with high adsorptive and optimal desorption characteristics. Phytic acid was isolated using the anion-exchange resin Purolite A200®. In addition, the processes resulted in two separated protein fractions. The ratios of globulin and albumin ratio to the total protein were 59.2% and 40.1%, respectively. The steps were then combined in two different ways: (a) a ‘sequential process’ using the zeolite and A200 in batch processes; and (b) a ‘parallel process’ using only A200 in a chromatographic system to separate all of the compounds. CONCLUSIONS It can be concluded that isolation of all three components was possible in both processes. These could enhance the added value of current processes using rapeseed meal as a protein source. © 2015 Society of Chemical Industry

Biotechnological production of valuables by microorganisms is commonly achieved by cultivating the cells as suspended solids in an appropriate liquid medium. However, the main portion of these organisms features a surface-attached growth in their native habitats. The utilization of such biofilms shows significant challenges, e.g. concerning control of pH, nutrient supply, and heat/mass transfer. But the use of biofilms might also enable novel and innovative production processes addressing robustness and strength of the applied biocatalyst, for example if variable conditions might occur in the process or a feedstock (substrate) is changed in its composition. Besides the robustness of a biofilm, the high density of the immobilized biocatalyst facilitates a simple separation of the catalyst and the extracellular product, whereas intracellular target compounds occur in a concentrated form; thus, expenses for downstream processing can be drastically reduced. While phototrophic organisms feature a fabulous spectrum of metabolites ranging from biofuels to biologically active compounds, the low cell density of phototrophic suspension cultures is still limiting their application for production processes. The review is focusing on pro- and eukaryotic microalgae featuring the production of valuable compounds and highlights requirements for their cultivation as phototrophic biofilms, i.e. setup as well as operation of biofilm reactors, and modeling of phototrophic growth.

Biodiversity forms the basis for a large pool of potential products and productive organisms offered by terrestrial cyanobacteria. They are stuck together by EPS (extracellular polymeric substances) that can obtain antiviral, antibacterial or anti-inflammatory substances. Most stress conditions, e.g. drought, induce the production of protective EPS or biotechnological-products for pharmaceutical application. However, the growth of a phototrophic biofilm is limited under submerged conditions. Therefore, a semi-continuous process to produce EPS by cyanobacteria was developed in an aerosol-based ePBR (emerse photobioreactor) that imitates the natural habitat of terrestrial cyanobacteria. The process consists of a growth-phase (biomass production), followed by a dry-phase (EPS-production) and a consecutive extraction. The EPS-productivities of Trichocoleus sociatus (ranging from 0.03 to 0.04 g L −1 d −1 ) were 32 times higher than described in topic-related literature. In comparison to submerge cultivations in shaking flasks, the EPS-productivities were sevenfold higher. To ensure that the extraction solvent has no influence on cell viability, a cell-vitality-test was performed. However, no statistically significant difference between the amount of living and dead cells before and after the extraction was detected. A bioactivity assay was then performed to identify antimicrobial activity within EPS extracts from emerse and submerge cultivations. The EPS revealed an antibacterial effect against gram-negative bacteria ( E. coli ) which was two times higher than EPS from a submerged cultivation.

Bei der Ferulasaure handelt es sich um einen Wertstoff, der aus Weizen gewonnen und in der Lebensmittel- und Pharmaindustrie eingesetzt werden kann. Der Einsatz von Weizen als nachwachsende Rohstoffquelle ist allerdings nur dann wirtschaftlich durchfuhrbar, wenn eine Prozessintegration in die bestehenden industriellen Verfahren gewahrleistet oder eine direkte Konkurrenz zur Mehl- und Starkeindustrie vermieden werden kann. In diesem Artikel wird ein Verfahren aufgezeigt, welches hohe Ausbeuten ermoglicht und eine Konkurrenz zu bestehenden Verwertungspfaden vermeidet. The application of wheat as a renewable resource for ferulic acid comes along with a high value addition of the crop. Nevertheless, it will only be suitable if process integration in existing industrial processes is possible and competition with other value-adding conversion of the raw material can be avoided. This article shows a new possibility of a downstream process resulting in high yields and without a competition to the flour and starch industry.

In this study, Nocardia iowensis was used to transform oleanolic acid (OA) into oleanane derivatives. The first derivative, which was found after 24 h of cultivation, was the known and already described OA methyl ester. After 1 week, two other derivatives (oleanonic acid methyl ester and an unknown metabolite) were identified as new products of a biotransformation by N. iowensis. These oleanane metabolites were characterized by HPLC, HPLC-ESI-MS, and HPLC-1H NMR spectroscopy. The biotransformation was performed by suspended and immobilized cells (ICs) of N. iowensis. Cells immobilized in alginate beads were used in order to prepare a continuous process. The substrate uptake of free and ICs was similar, whereas the peak area of OA methyl ester of the ICs was only about 10% of the native cells. However, the final product (oleanonic acid methyl ester) concentrations were similar in both approaches, whereas the unknown metabolite 3 was only detected transiently in the medium of ICs. Based on these results, a new biosynthetic pathway for the biotechnological production of oleanonic acid methyl ester is proposed.

Biotechnologie und die mit ihr verbundenen technischen Prozesse pragen seit Jahrtausenden die Entwicklung der Menschheit. Ausgehend von empirischen Verfahren, insbesondere zur Herstellung von Lebensmitteln und taglichen Gebrauchsgutern, haben sich diese Disziplinen zu einem der innovativsten Zukunftsfelder entwickelt. Durch das immer detailliertere Verstandnis zellularer Vorgange konnen mittlerweile Produktionsstamme gezielt optimiert werden. Im Zusammenspiel mit moderner Prozesstechnik konnen so eine Vielzahl von Bulk- und Feinchemikalien sowie Pharmazeutika effizient hergestellt werden. In diesem Artikel werden exemplarisch einige der aktuellen Trends vorgestellt. Since several thousand years, biotechnology and its associated technical processes have great impact on the development of mankind. Based on empirical methods, in particular for the production of foodstuffs and daily commodities, these disciplines have become one of the most innovative future issues. Due to the increasing detailed understanding of cellular processes, production strains can now be optimized. In combination with modern bioprocesses, a variety of bulk and fine chemicals as well as pharmaceuticals can be produced efficiently. In this article, some of the current trends in biotechnology are discussed.

Bei der Gewinnung von Fettsauren aus Pflanzenolen, z. B. zur Herstellung von Biopolymeren, oder bei der Biodiesel- und Seifenproduktion, fallt Glycerin als Nebenprodukt an. Bei der Biokonversion dieses Rohstoffes zu 1,3-Propandiol wird der Produktionsorganismus Clostridium diolis durch Verunreinigungen im Rohglycerin gehemmt. Als inhibierende Substanzen konnten freie Fettsauren identifiziert werden. Mithilfe eines adsorptiven Aufarbeitungsverfahrens ist es gelungen, die Fettsauren zu entfernen und die Konversionseffizienz zu 1,3-Propandiol zu erhohen. During the production of fatty acids from plant oils, e. g. for the production of biopolymers or in the biodiesel and soap production, glycerol accumulates as a side product. Using this residual material with Clostridium diolis for the production of 1,3-propanediole is not efficient, due to inhibitory effects of impurities. Fatty acids have been identified as inhibiting substances. After removal of the residual fatty acids by pretreatment with adsorbents, it has been possible to use this glycerol with high conversion efficiency towards 1,3-propanediole.

A new, highly specific toluidine blue assay for the determination of sulfated polysaccharides is reported. Sulfated polysaccharides may be specifically determined at pH 1 in the presence of carboxylated polysaccharides and phosphorylated molecules such as nucleic acids. In addition, performing the assay at pH 1 extended the linear dynamic range for fucoidan up to 3 g/L but lowered the sensitivity in comparison with pH 7. For a color change at neutral pH, at least a sulfated disaccharide is required, whereas at pH 1, the detection was negative even for a sulfated maltose. A comparison of the fucoidan concentration in crude algae determined by the toluidine blue assay at pH 1 and gel permeation chromatography confirmed the accuracy and specificity of the colorimetric method. The limit of quantitation for the toluidine blue assay at pH 1 was 0.62 g/L for fucoidan. For a deeper understanding of the interaction between the sulfated polysaccharides and the toluidine blue, spectroscopic constants were evaluated by Ketelaar plots for sulfate esters. The maximum value for the molar absorptivity was 4.07 × 104 L/(mol cm), indicating strong affinity. Similar behavior was obtained for fucoidan at pH 7 with a value of 4.46 × 103 L/mol.

A comparative study concerning the physicochemical, monomeric composition and biological characters among different fucoidan fractions is presented. Common purification techniques for fucoidan usually involve many steps. During these steps, the important structural features might be affected and consequently alter its biological activities. Three purified fractions were derived from Fucus vesiculosus water extract which, afterwards, were purified by a recently-developed dye affinity chromatography protocol. This protocol is based on dye-sulfated polysaccharide interactions. The first two fractions were obtained from crude precipitated fucoidan at different pH values of the adsorption phase: pH 1 and 6. This procedure resulted in fucoidan_1 and 6 fractions. The other, third, fraction: fucoidan_M, however, was obtained from a buffered crude extract at pH 1, eliminating the ethanol precipitation step. All of the three fractions were then further evaluated. Results revealed that fucoidan_M showed the highest sulfur content (S%), 12.11%, with the lowest average molecular weight, 48 kDa. Fucose, galactose, and uronic acid/glucose dimers were detected in all fractions, although, xylose was only detected in fucoidan_1 and 6. In a concentration of 10 µg·mL−1, Fucoidan_6 showed the highest heparin-like anticoagulant activity and could prolong the APTT and TT significantly to 66.03 ± 2.93 and 75.36 ± 1.37 s, respectively. In addition, fucoidan_M demonstrated the highest potency against HSV-1 with an IC50 of 2.41 µg·mL−1. The technique proved to be a candidate for fucoidan purifaction from its crude extract removing the precipitation step from common purification protocols and produced different fucoidan qualities resulted from the different incubation conditions with the immobilized thiazine toluidine blue O dye.

Sulfated polysaccharides, such as the so-called fucoidans, from brown algae exhibit a versatile biological activity, which is thought to be associated with their characteristic sulfated fucose backbone. The extraction of the target compound is one of the most important steps of the purification process. The correct adjustment of parameters, such as temperature, pH, and extraction time, greatly influences the yield and prevents the possible structural alteration of the sulfated polysaccharides. This review includes historical and current extraction procedures for sulfated polysaccharides and illustrates novel extraction techniques, which can effectively improve the extraction process. The use of ultrasound- and microwave-assisted extraction techniques is described, the potential of which has been underestimated to date. Furthermore, the enzyme-assisted extraction of fucoidans is in its infancy. It is assumed that further improvements of these procedures (e.g., by the application of computer-aided techniques) will have a major impact on the economics and the scalability of the extraction process as well as yielding a sugar fraction with a conserved sulfation pattern.

An IR microscope has been installed at the beamline ID18 at the ESRF in Grenoble, France in order to obtain nuclear inelastic scattering (NIS) data and IR spectra simultaneously. This setup combines the advantages of both spectroscopic methods. The applicability of the installed setup to the study of the spin crossover (SCO) phenomenon in polynuclear iron complexes has been shown.

The vibrational properties of Fe(II) 1D spin crossover polymers have been characterized by nuclear inelastic scattering (NIS). The complexes under study were the tosylate and perchlorate salts of ([Fe(4-amino-1,2,4-triazole)3]\(^{+2})_{\rm n}\) complexes. The complexes have LS (S = 0) marker bands in the range of 300–500 cm − 1, while the marker bands corresponding to the HS (S = 2) state are detected between 200 cm − 1 and 300 cm − 1, in line with the decreasing Fe-N bond strengths during the transition from LS to HS. Accompanying DFT calculations using the functional B3LYP and the basis set CEP-31G confirm these assignments.

Grass silage provides a great potential as renewable feedstock. Two fractions of the grass silage, a press juice and the fiber fraction, were evaluated for their possible use for bioethanol production. Direct production of ethanol from press juice is not possible due to high concentrations of organic acids. For the fiber fraction, alkaline peroxide or enzymatic pretreatment was used, which removes the phenolic acids in the cell wall. In this study, we demonstrate the possibility to integrate the enzymatic pretreatment with a simultaneous saccharification and fermentation to achieve ethanol production from grass silage in a one-process step. Achieved yields were about 53 g ethanol per kg silage with the alkaline peroxide pretreatment and 91 g/kg with the enzymatic pretreatment at concentrations of 8.5 and 14.6 g/L, respectively. Furthermore, it was shown that additional supplementation of the fermentation medium with vitamins, trace elements and nutrient salts is not necessary when the press juice is directly used in the fermentation step.

Triterpenes are a versatile group of biologically active ingredients present in several phytoextracts. They often occur as glycoconjugates with a distinct bioactivity from their aglycone counterparts. Deglycation of triterpenes can be performed by enzymatic and chemical reactions, whereas biotransformation is generally more specific and occurs without unwanted alterations to the molecule. Further structural modification of the triterpenes to enhance their pharmaceutical relevance can be efficiently carried out by the application of biotransformational processes using microorganisms or isolated enzymes. In particular, the whole-cell process is favorable if cofactor-dependent modifications are preferred, such as hydroxylations/oxidations of the lead compound. However, the isolation of triterpenes from domestic plant material has some disadvantages such as extract variability and instability. These problems can be overcome through the use of cell culture technology, where the ex vivo cultivated cells are used for the reproducible production of the target compound. The relevant topics that should be addressed to establish a (biotransformational) production process of pharmaceutically relevant triterpenes are covered in this review. In particular, we focus on the production process using tissue engineering, the corresponding analytical techniques, and the biotransformation reaction required to obtain bioactive compounds from precursor molecules.

Biokatalysatoren zur regioselektiven Halogenierung bestimmter Substrate sind mittlerweile verfugbar. Ein Einsatz solcher Halogenasen zur Bereitstellung halogenierter (Zwischen-) Produkte bietet im Vergleich zur klassischen Halogenierung den Vorteil, dass sie weitgehend nebenproduktfrei ablauft und keine toxischen Halogenierungsagentien zur Anwendung kommen. Beispielhaft wird hier die Untersuchung kinetischer Parameter einer Tryptophan-5-Halogenase beschrieben.

Classical energy sources such as petroleum oil and natural gas make up the fundamental materials on which modern industrial chemical parks are based. According to the finite availability of these consuetudinary resources and due to the increasing demand for energy from developing countries and the related rise in prices of oil and natural gas, renewable resources must be considered as valuable alternatives. Discussions about climate change with regard to alternatives in energy production are preceded very fervidly but alternatives have to be examined from a matter-of-fact based economic and scientific point of view. Therefore, this review is focussed on alternative sources such as wood and other agricultural residues with respect to their potential as future energy resources as well as building blocks for chemical synthesis processes.

The measurement of force–distance curves on a single bacterium provides a unique opportunity to detect properties such as the turgor pressure under various environmental conditions. Marine bacteria are very interesting candidates for the production of pharmaceuticals, but are only little studied so far. Therefore, the elastic behavior of Paracoccus seriniphilus, an enzyme producing marine organism, is presented in this study. After a careful evaluation of the optimal measurement conditions, the spring constant and the turgor pressure are determined as a function of ionic strength and pH. Whereas the ionic strength changes the turgor pressure passively, the results give a hint that the change to acidic pH increases the turgor pressure by an active mechanism. Furthermore, it could be shown, that P. seriniphilus has adhesive protrusions outside its cell wall.

The oceans provide an almost untapped reservoir of novel enzymes which might have a potential as biocatalysts for academic research and for industrial processes. With regard to the broad variety of environmental conditions, interesting enzymes with characteristic traits can be isolated. Especially enzymes from extremophiles, which are classified as thermophilic or psychrophilic, are of particular interest for industrial processes in terms of mass transfer or energy savings. Additionally, enzymes which are adapted towards high salt concentrations may be beneficial for industrial biotechnology applications, because the catalytic reactions can be performed in non-diluted solutions. Up to now only a minor amount of this treasure has found an application in the laboratory and industry. However, regarding the ongoing progress and developments in molecular biology it seems that the portfolio of enzymes that can be applied for the production of bulk and fine chemicals will be broadened in the near future. In this chapter an exemplary overview about the research work done on the production of enzymes from marine origin, as well as their potential application in industrial processes is given.