New publication: Membrane-free dissolved hydrogen monitoring in anaerobic digestion

Dissolved hydrogen (dH2) is an important parameter in anaerobic digestion (AD) processes, in particular in a two-stage operation mode encompassing separate hydrolytic/acidogenic and methanogenic stages. Then, monitoring of dH2 as a substrate of hydrogenotrophic methanogenesis is essential to avoid feast and famine conditions. Despite its significance, there is currently a lack of established monitoring systems which are capable of reliably measuring dH2 concentrations in culture broth. To address this challenge, we propose a novel measurement system, which is based on the membrane-free extraction of hydrogen in an extraction chamber and the subsequent analysis by a metal-oxide (MOX) gas sensor. The response time of the MOX sensor lies in the range of seconds, while the entire measurement process completes within a total processing time of about 70 min). This study explores the measurement performance of the dH2 sensor in the hydrolytic/acidogenic and methanogenic stage during lab-scale anaerobic digestion. „New publication: Membrane-free dissolved hydrogen monitoring in anaerobic digestion“ weiterlesen

Agilent awards Prof. Peter Neubauer with Thought Leader Award

Agilent Technologies Inc. proudly honors Prof. Dr. Peter Neubauer, Chair of Bioprocess Engineering and the KIWI-biolab at the Technische Universität Berlin, with the distinguished Agilent Thought Leader Award. Prof. Neubauer’s pioneering research in bioprocess development, particularly in genetic, cultivation, and analytical methodologies, has earned him this prestigious accolade.

His innovative work revolves around enhancing bioprocess development efficiency, with a strong focus on industrial-scale applications. By leveraging automation and high throughput techniques, he advances real-time evaluation of critical quality attributes (CQAs), a critical facet of optimizing biotechnological processes.

Substantial resources are dedicated to the development of process analytical technology (PAT) to ensure pharmaceutical manufacturing process integrity. Prof. Neubauer seamlessly integrates hardware, software, automation, mathematical models, and AI to optimize end-to-end PAT workflows. This integration of intelligent technologies and automation paves the way for safer and more efficient bioprocesses.

The Agilent Thought Leader Award propels Prof. Neubauer’s ongoing research, spanning challenges from intricate protein expression to scale-up strategies. „Agilent’s award allows us to incorporate advanced instrumentation like two-dimensional liquid chromatography and mass spectrometry,“ says Prof. Neubauer. „This support drives us towards achieving higher levels of automated bioprocess development.“

Sudharshana Seshadri, VP and General Manager of Agilent’s Liquid Chromatography, Mass Spectrometry, and Automation Divisions, lauds Dr. Neubauer’s impact: „Agilent proudly presents the Thought Leader Award to Dr. Neubauer, recognizing his groundbreaking contributions to biopharma science. His work propels the pharmaceutical industry towards optimized bioprocesses, advancing global healthcare.“

The Agilent Thought Leader Award program empowers scientific progress by offering financial support, cutting-edge products, and expertise to influential thought leaders in life sciences, diagnostics, and chemical analysis. Learn more at the Agilent Thought Leader Award website.

New publication: Controlling Aspergillus niger morphology in a low shear-force environment

The filamentous fungus Aspergillus niger is an important production host in biotechnology. Shear force regimes are one of the key factors that affect macromorphology and product yield. While morphology changes under intensive agitation have been widely investigated, studies at a low shear force regime independently from oxygen limitation has remained a challenge. Therefore, in a new publication of ours, a 2-dimensional rocking-motion bioreactor is used as an alternative platform for studying the macromorphology under a low shear force regime, but sufficient supply of dissolved oxygen. Talcum macroparticles were added at different concentrations to control the development of a certain macromorphology.

Fig.: Selected differential interference contrast (DIC) microscopy images of Aspergillus niger macromorphology with various talcum concentrationsas obtained in a 2-dimensional rocking-motion CELL-tainer CT 20 single-use bioreactor in fed-batch mode. The the macromorphology changed from fully dispersed hyphae at 1% w/v to formation of clumps at 0.25% w/v talcum.

„New publication: Controlling Aspergillus niger morphology in a low shear-force environment“ weiterlesen

New publication: Bioaugmentation improves hydrolysis of residual biomass

Concept of bioaugmentation in a PFR
Concept of Bioaugmentation in a Plug-flow Reactor based Hydrolysis Stage.

Residual biomass is a valuable resource for the production of energy (biogas, hydrogen) and carboxylic acids. However, the locally available biomass can often not be fermented efficiently in anaerobic digestion – as is the case for lignocellulosic feedstock like straw which is widely available as residue. Thus, at the chair of bioprocess engineering at TU Berlin, as part of the ‘HydroFLEX’ project, funded by the Fachagentur für nachwachsende Rohstoffe, we used a plug-flow reactor and targeted addition of specific bacteria with hydrolytic activity (bioaugmentation) to support the microbial hydrolysis of various feedstock, in this case maize silage and bedding straw from a horse stable. As described in our recent publication, we found that the added microbes increased the yield of soluble metabolites and acids. We found in our study that this was especially efficient for maize silage. Nevertheless, also with a high content of 66 % straw in the reactor, the added microbes increased the acid yield by up to 21 %. The plug-flow reactor, which features gradient formation in the liquid phase and the partly recirculation of the thin-sludge, further improved the process by the formation of microenvironments for specialized microbes.

„New publication: Bioaugmentation improves hydrolysis of residual biomass“ weiterlesen

99 € Bioreactor Competition 2022

Six students, one mission. To win a price at this year’s 99 €-Bioreactor competition in Dresden. And that despite pandemic-related teaching at the university for the last two years. Impossible? Not for us.

The Netzwerk Bioverfahrenstechnik Dresden e.V. challenged all teams to produce high amounts of pigment using the microorganism Micrococcus luteus. With a budget of 99 €, we had to build a bioreactor that would be home to the microorganism in Dresden for 24 hours and have all the features that would enable high pigment and biomass production. Our team “Pigmentoren” consisted of six TUB students (Louisa Henschke, Per-Alexander Paul, Falk Schimweg and Sophie Wozniak, Enerel Ariunbold) and was led by PhD student Isabel Thiele.

Micrococcus luteus? Isn’t that the yellow bacteria flying around in the air on a daily basis? Yes! However, its yellow pigment has much more to offer and proves to be a true multi-talent. Its antimicrobial properties, protection against harmful UV radiation, anti-oxidative efficacy and usability as a natural dye make it a highly interesting substance for the food and cosmetics industries as well as in the health sector.

Our 99 € Bioreactor

An old mixer served as the vessel and motor for our bioreactor.
Since the bacterium is aerobic, good aeration and turbulence are essential. For this, we crafted a ring sparger out of „99 € Bioreactor Competition 2022“ weiterlesen

Novel tissue adhesive for human and dental medicine

Working principle of the patented bioglue.

We have developed a biocompatible adhesive that can be used for bone fractures and injuries. Nearly one in two people suffer from inflammation of the tooth bed, known as periodontitis, in the course of their lives. Periodontal disease begins with a bacterial inflammation of the gums. For treatment, depending on the severity of the periodontitis, a closed or open scraping of the tooth necks is performed. During this procedure, the gum is slightly detached from the affected area, the exposed areas are cleaned and, if necessary, diseased tissue is gently removed. In the future, a tissue adhesive is to be placed in the cleaned gap in order, on the one hand, to reattach the gum to the tooth neck and, on the other hand, to prevent new colonization of the tooth neck surface through its antibacterial properties.

In the Dental-Fix project, we are investigating whether a biosynthetic tissue adhesive, developed on the basis of a mussel protein, can be used in human and dental medicine.  More information (in German)

Cooperation and new Publication with Columbian Cooperators

For many years, the laboratory has maintained close relations with various Columbian institutions. We are grateful for the very good cooperation over all these years! Within this framework, research stays were realized, which made it possible to support work in the field of microbial and plant cell cultivation, the scale down of bioprocesses and the development of biomass utilization concepts. Numerous visits to conduct workshops and many joint publications show the fruits of all these years of cooperation.

Representatives from TU Berlin visiting Universidad de Antiochia in Columbia for a Symposium on Bioprocess Engineering in December 2021. Collaborators Rigoberto Rios (left) and Silvia Ochoa (3rd person from the left) and TUB-bioprocess engineering lab members (from the right) Jasmina Cziommer, Isabel Thiele, Lara Santolin, Björn Gutschmann and Stefan Junne.

In the „BioForS“ project, which was funded by the German Federal Ministry of Education and Research (grant no. 01DN19005) and MINCENCIAS, the focus was, together with SME networks, on method development for several bioprocesses for the production of pharmaceutically important molecules, but also bio-based bulk chemicals. In this context, a group of researchers from TU Berlin visited the research institutions Universidad del Valle in Cali and Universidad de Antiochia in Medellin in December 2021. In public symposia, research work was presented to each other and the basis for further cooperation in the coming years was established. The currently funded „WasteValor“ project (grant no. 01DN21003) is now pursuing systemic approaches to value creation in rural regions and in interaction with urban areas by means of biotechnological processes. „Cooperation and new Publication with Columbian Cooperators“ weiterlesen

PHA team goes to larger scale

In April 2022, our PHA team travelled to Penang (Malaysia) to run 2 x 750 L-scale cultivations as part of the PHABio-up project at the Universiti Sains Malaysia (USM) in collaboration with Prof. Kumar Sudesh and his team.

Our PHA team at the Innovative Incubator University (I2U) fermentation facility at USM. From left to right: M. Sc. Isabel Thiele, M. Sc. Björn Gutschmann, M. Sc. Saskia Waldburger, Dr.- Ing. Sebastian L. Riedel, B. Sc. Matilde Maldonado Simões and M. Sc. Lara Santolin.

Using waste triglycerides as feedstock TU Berlin and USM joined forces and produced 50 kg of polyhydroxyalkanoate (PHA) bioplastic-rich Ralstonia eutropha cells. For inoculating the 750-L bioreactor the seed train involved streaking out the used R. eutropha strain on agar plates, growing a first shake-flask preculture, then going into a 13‑L lab scale bioreactor and finally to a 150-L pilot scale bioreactor as a third preculture. The main cultivations in the 750-L bioreactor were run for 3 days enabling the cells to undergo first a biomass accumulation stage and then triggering PHA accumulation through nitrogen limitation. The cells, that accumulate the polymer as a carbon and energy reservoir when facing stress conditions, had stored around 70% of their cell dry weight as PHA at the timepoint of harvesting. For recovery of the PHA, the harvest was drum-dried and fed to mealworms that had consumed the biomass and excreted the PHA granules in the form of whitish feces that were finally washed to reach high-purity PHA.

Producing PHA bioplastic: 1: Feedstock. 2: Preculture in 150-L pilot scale bioreactor. 3: Main culture in 750-L bioreactor. 4: Drum-drying the harvest. 5: Drum-dried biomass rolls. 6: Green recovery with mealworms. 7: Washed mealworm feces (PHA).

It took a big team of 20 people and 3 weeks of very hard work with non-stop shifts „PHA team goes to larger scale“ weiterlesen

New publication out about lichen cultivation!

Due to their huge biodiversity and the capability to produce a wide range of secondary metabolites, lichens have a great potential in biotechnological applications. They have, however, hardly been used as cell factories to date, as it is considered to be difficult and laborious to cultivate lichen partners in pure or co-culture in the laboratory. The various methods used to isolate lichen fungi, based on either the ascospores, the conidia, or the thallus, have so far not been compared or critically examined. Therefore, we systematically investigated and compared the known and new methods to identify the most suitable technology for isolation for lab cultivations. more…

Isolation of fungi in lichen: A Germinated ascospores of Protoparmeliopsis muralis after 6 days (200 × magnification); Colony formation after 75 days of B Circinaria contorta (20 × magnification); C Xanthoria parietina (20 × magnification) and D P. muralis (40 × magnification)