@article{HoffstadtCheenakulaNikolauszetal.2023, author = {Hoffstadt, Kevin and Cheenakula, Dheeraja and Nikolausz, Marcell and Krafft, Simone and Harms, Hauke and Kuperjans, Isabel}, title = {Design and construction of a new reactor for flexible biomethanation of hydrogen}, series = {Fermentation}, volume = {9}, journal = {Fermentation}, number = {8}, publisher = {MDPI}, address = {Basel}, issn = {2311-5637}, doi = {10.3390/fermentation9080774}, pages = {1 -- 16}, year = {2023}, abstract = {The increasing share of renewable electricity in the grid drives the need for sufficient storage capacity. Especially for seasonal storage, power-to-gas can be a promising approach. Biologically produced methane from hydrogen produced from surplus electricity can be used to substitute natural gas in the existing infrastructure. Current reactor types are not or are poorly optimized for flexible methanation. Therefore, this work proposes a new reactor type with a plug flow reactor (PFR) design. Simulations in COMSOL Multiphysics ® showed promising properties for operation in laminar flow. An experiment was conducted to support the simulation results and to determine the gas fraction of the novel reactor, which was measured to be 29\%. Based on these simulations and experimental results, the reactor was constructed as a 14 m long, 50 mm diameter tube with a meandering orientation. Data processing was established, and a step experiment was performed. In addition, a kLa of 1 h-1 was determined. The results revealed that the experimental outcomes of the type of flow and gas fractions are in line with the theoretical simulation. The new design shows promising properties for flexible methanation and will be tested.}, language = {en} } @article{ElBerguiAbouabdillahBouriougetal.2023, author = {El Bergui, Omnia and Abouabdillah, Aziz and Bourioug, Mohamed and Schmitz, Dominik and Biel, Markus and Aboudrare, Abdellah and Krauss, Manuel and Jomaa, Ahlem and Romuli, Sebastian and M{\"u}ller, Joachim and Fagroud, Mustapha and Bouabid, Rachid}, title = {Innovative solutions for drought: Evaluating hydrogel application on onion cultivation (Allium cepa) in Morocco}, series = {Water}, volume = {15}, journal = {Water}, number = {11}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/w15111972}, pages = {Artikel 1972}, year = {2023}, abstract = {Throughout the last decade, and particularly in 2022, water scarcity has become a critical concern in Morocco and other Mediterranean countries. The lack of rainfall during spring was worsened by a succession of heat waves during the summer. To address this drought, innovative solutions, including the use of new technologies such as hydrogels, will be essential to transform agriculture. This paper presents the findings of a study that evaluated the impact of hydrogel application on onion (Allium cepa) cultivation in Meknes, Morocco. The treatments investigated in this study comprised two different types of hydrogel-based soil additives (Arbovit® polyacrylate and Huminsorb® polyacrylate), applied at two rates (30 and 20 kg/ha), and irrigated at two levels of water supply (100\% and 50\% of daily crop evapotranspiration; ETc). Two control treatments were included, without hydrogel application and with both water amounts. The experiment was conducted in an open field using a completely randomized design. The results indicated a significant impact of both hydrogel-type dose and water dose on onion plant growth, as evidenced by various vegetation parameters. Among the hydrogels tested, Huminsorb® Polyacrylate produced the most favorable outcomes, with treatment T9 (100\%, HP, 30 kg/ha) yielding 70.55 t/ha; this represented an increase of 11 t/ha as compared to the 100\% ETc treatment without hydrogel application. Moreover, the combination of hydrogel application with 50\% ETc water stress showed promising results, with treatment T4 (HP, 30 kg, 50\%) producing almost the same yield as the 100\% ETc treatment without hydrogel while saving 208 mm of water.}, language = {en} } @article{HaegerProbstJaegeretal.2023, author = {Haeger, Gerrit and Probst, Johanna and Jaeger, Karl-Erich and Bongaerts, Johannes and Siegert, Petra}, title = {Novel aminoacylases from Streptomyces griseus DSM 40236 and their recombinant production in Streptomyces lividans}, series = {FEBS Open Bio}, volume = {13}, journal = {FEBS Open Bio}, number = {12}, publisher = {Wiley}, address = {Hoboken, NJ}, issn = {2211-5463}, doi = {10.1002/2211-5463.13723}, pages = {2224 -- 2238}, year = {2023}, abstract = {Amino acid-based surfactants are valuable compounds for cosmetic formulations. The chemical synthesis of acyl-amino acids is conventionally performed by the Schotten-Baumann reaction using fatty acyl chlorides, but aminoacylases have also been investigated for use in biocatalytic synthesis with free fatty acids. Aminoacylases and their properties are diverse; they belong to different peptidase families and show differences in substrate specificity and biocatalytic potential. Bacterial aminoacylases capable of synthesis have been isolated from Burkholderia, Mycolicibacterium, and Streptomyces. Although several proteases and peptidases from S. griseus have been described, no aminoacylases from this species have been identified yet. In this study, we investigated two novel enzymes produced by S. griseus DSM 40236ᵀ . We identified and cloned the respective genes and recombinantly expressed an α-aminoacylase (EC 3.5.1.14), designated SgAA, and an ε-lysine acylase (EC 3.5.1.17), designated SgELA, in S. lividans TK23. The purified aminoacylase SgAA was biochemically characterized, focusing on its hydrolytic activity to determine temperature- and pH optima and stabilities. The aminoacylase could hydrolyze various acetyl-amino acids at the Nα -position with a broad specificity regarding the sidechain. Substrates with longer acyl chains, like lauroyl-amino acids, were hydrolyzed to a lesser extent. Purified aminoacylase SgELA specific for the hydrolysis of Nε -acetyl-L-lysine was unstable and lost its enzymatic activity upon storage for a longer period but could initially be characterized. The pH optimum of SgELA was pH 8.0. While synthesis of acyl-amino acids was not observed with SgELA, SgAA catalyzed the synthesis of lauroyl-methionine.}, language = {en} } @book{Lauth2023, author = {Lauth, Jakob}, title = {Physical chemistry in a nutshell: Basics for engineers and scientists}, publisher = {Springer}, address = {Berlin}, isbn = {978-3-662-67636-3 (Softcover)}, doi = {10.1007/978-3-662-67637-0}, pages = {XIII, 248 Seiten}, year = {2023}, abstract = {This book is based on a multimedia course for biological and chemical engineers, which is designed to trigger students' curiosity and initiative. A solid basic knowledge of thermodynamics and kinetics is necessary for understanding many technical, chemical, and biological processes. The one-semester basic lecture course was divided into 12 workshops (chapters). Each chapter covers a practically relevant area of physical chemistry and contains the following didactic elements that make this book particularly exciting and understandable: - Links to Videos at the start of each chapter as preparation for the workshop - Key terms (in bold) for further research of your own - Comprehension questions and calculation exercises with solutions as learning checks - Key illustrations as simple, easy-to-replicate blackboard pictures Humorous cartoons for each workshop (by Faelis) additionally lighten up the text and facilitate the learning process as a mnemonic. To round out the book, the appendix includes a summary of the most popular experiments in basic physical chemistry courses, as well as suggestions for designing workshops with exhibits, experiments, and "questions of the day." Suitable for students minoring in chemistry; chemistry majors are sure to find this slimmed-down, didactically valuable book helpful as well. The book is excellent for self-study.}, language = {en} }