Newest publications
Glucoselipid biosurfactant biosynthesis operon of Rouxiella badensis DSM 100043T: screening, identification, and heterologous expression in Escherichia coli
(2025) Harahap, Andre Fahriz Perdana; Treinen, Chantal; Van Zyl, Leonardo Joaquim; Williams, Wesley Trevor; Conrad, Jürgen; Pfannstiel, Jens; Klaiber, Iris; Grether, Jakob; Hiller, Eric; Vahidinasab, Maliheh; Perino, Elvio Henrique Benatto; Lilge, Lars; Burger, Anita; Trindade, Marla; Hausmann, Rudolf; Seo, Myung-Ji
Rouxiella badensis DSM 100043T had been previously proven to produce a novel glucoselipid biosurfactant which has a very low critical micelle concentration (CMC) as well as very good stability against a wide range of pH, temperature, and salinity. In this study, we performed a function-based library screening from a R. badensis DSM 100043T genome library to identify responsible genes for biosynthesis of this glucoselipid. The identified open reading frames (ORFs) were cloned into several constructs in Escherichia coli for gene permutation analysis and the individual products were analyzed using high-performance thin-layer chromatography (HPTLC). Products of interest from positive expression strains were purified and analyzed by liquid chromatography/electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) and nuclear magnetic resonance (NMR) for further structure elucidation. Function-based screening of 5400 clones led to the identification of an operon containing three ORFs encoding acetyltransferase GlcA (ORF1), acyltransferase GlcB (ORF2), and phosphatase/HAD GlcC (ORF3). E. coli pCAT2, with all three ORFs, resulted in the production of identical R. badensis DSM 100043T glucosedilipid with Glu-C10:0-C12:1 as the main congener. ORF2-deletion strain E. coli pAFP1 primarily produced glucosemonolipids, with Glu-C10:0,3OH and Glu-C12:0 as the major congeners, predominantly esterified at the C-2 position of the glucose moiety. Furthermore, fed-batch bioreactor cultivation of E. coli pCAT2 using glucose as the carbon source yielded a maximum glucosedilipid titer of 2.34 g/L after 25 h of fermentation, which is 55-fold higher than that produced by batch cultivation of R. badensis DSM 100043T in the previous study.
Integrating sensor data, laboratory analysis, and computer vision in machine learning-driven E-Nose systems for predicting tomato shelf life
(2025) Senge, Julia Marie; Kaltenecker, Florian; Krupitzer, Christian
Assessing the quality of fresh produce is essential to ensure a safe and satisfactory product. Methods to monitor the quality of fresh produce exist; however, they are often expensive, time-consuming, and sometimes require the destruction of the sample. Electronic Nose (E-Nose) technology has been established to track the ripeness, spoilage, and quality of fresh produce. Our study developed a freshness monitoring system for tomatoes, combining E-Nose technology with storage condition monitoring, color analysis, and weight-loss tracking. Different post-purchase scenarios were investigated, focusing on the influence of temperature and mechanical damage on shelf life. Support Vector Classifier (SVC) and k-Nearest Neighbor (kNN) were applied to classify storage scenarios and storage days, while Support Vector Regression (SVR) and kNN regression were used for predicting storage days. By using a data fusion approach with Linear Discriminant Analysis (LDA), the SVC achieved an accuracy of 72.91% in predicting storage days and an accuracy of 86.73% in distinguishing between storage scenarios. The kNN yielded the best regression results, with a Mean Absolute Error (MAE) of 0.841 days and a coefficient of determination of 0.867. The results highlight the method’s potential to predict storage scenarios and storage days, providing insight into the product’s remaining shelf life.
Last editorial Kredit und Kapital/Credit and capital markets
(2024) Burghof, Hans-Peter; Hakenes, Hendrik; Neyer, Ulrike
Urban waste fertilizer: effects on yield, nutrient dynamics, and potentially toxic element accumulation
(2025) Reimer, Marie; Möller, Kurt; Magid, Jakob; Bruun, Sander
Recycling nutrients contained in urban wastes to agriculture is essential in a circular economy. This study simultaneously compares different recycled fertilizers (household waste compost, sewage sludge, human urine) with mineral fertilization and animal manures. Tested were their long-term effects on yield, nutrient budgets, potentially toxic element (PTE) accumulation, and nitrogen (N)/carbon (C) cycle (among others N efficiency, N losses, soil C). Therefore, data from a long-term field trial and predictions from the soil–plant-atmosphere model Daisy were evaluated. Based on trial data, human urine performed similar to the mineral fertilization for yield, N efficiency (mineral fertilizer equivalent (MFE) = 81%), and nutrient budget, while sewage sludge and compost were comparable to animal manures in terms of having lower yields, N efficiencies (MFE 70% and 19% respectively) and higher nutrient imbalances, especially P and S surpluses. Compost and sewage sludge applications resulted in net PTE inputs. Yet, plant uptake and soil accumulation seemed neglectable. Model outputs predicted N losses of 34–55% of supplied N. Losses were highest for compost, followed by deep litter, manure, sewage sludge, human urine, mineral fertilization, and slurry. Nitrate leaching was the main loss pathway (14–41% of N input). Within the compost and straw-rich manure fertilization, about 25% of applied N was stored in the soil which was accompanied by an increase in soil C. The study suggests substitution of established fertilizers with recycled ones is feasible. Thereby each fertilizer has advantages and disadvantages and thus should be utilized according to its strength or in mixtures.
Market-based instruments for biodiversity in agricultural landscapes: An evaluation of quality criteria in a German case study
(2025) Streit, Lea; Feuerbacher, Arndt; Röhl, Markus
Market-based instruments (MBIs) for the protection and promotion of biodiversity have gained significant importance in recent years. The success of MBIs depends largely on the transparent presentation of their actual effects, which rely on the quality of implementation. Quality criteria can be used to evaluate this. To date, few studies have examined whether and how these criteria are applied. This study seeks to address this gap, by using MBIs in the German agricultural landscape as a case study. Quality criteria were defined on the basis of a literature review; then applied to MBIs identified through an internet search and finally analyzed. Quality criteria related to methodological approaches (implementation, maintenance, used seed mixtures) and quality control (monitoring, localization) are presented less frequently than information on rights and obligations or the use of financial funds. Among the 151 MBIs analyzed, 70% lack control mechanisms and monitoring systems, indicating unverified effectiveness. Additionally, MBIs financed through program approaches are more likely to have control mechanisms and include perennial measures than MBIs funded by direct payments of sponsors or consumers purchasing a product. The development of MBI offerings suggests that there is persistent and growing demand, as some programs have been running for several decades. However, without ecological monitoring, it is not possible to ascertain whether these measures benefit biodiversity. To establish standardized methods for comparing MBIs for biodiversity, policymakers must consider official guidelines and, where appropriate, implement regulatory frameworks.