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Bioaccessibility and anti-inflammatory activity in Caco-2 cells of phytochemicals from industrial by-products of coffee (Coffea arabica L.)
(2025) Jiménez-Gutiérrez, Milena; Zielinski, Christian; Esquivel, Patricia; Frank, Jan; Irías-Mata, Andrea; Jiménez-Aspee, Felipe
Coffee by-products are rich in nutrients and bioactive compounds in free soluble form and bound to cell wall components. These compounds undergo chemical changes during gastrointestinal digestion, affecting their bioaccessibility and bioactivity. This study is the first to investigate coffee by-products from industrial wet processing to evaluate the impact of simulated gastrointestinal digestion on their phytochemical composition and subsequent anti-inflammatory activity in Caco-2 cells. Digestion significantly reduced the stability and solubility of main compounds; however, digested bioaccessible by-products still exhibited anti-inflammatory properties, reducing IL-6, IL-8, and TNF-α levels. Correlation analysis identified rutin, quercetin-3-glycoside, caffeine and 5-caffeoylquinic acid as strongly linked to cytokine suppression, suggesting key roles and possible synergies. These results highlight the potential of coffee by-products as functional ingredients targeting intestinal inflammation. Future work should confirm in vivo efficacy, optimize extraction at scale, and address regulatory requirements to support industrial application and promote circular economy benefits.
Can market fragmentation explain the limited success of political attempts to promote grain legume cultivation in Germany?
(2025) Mittag, Franziska; Hess, Sebastian
Grain legumes, such as field peas, field beans, sweet lupins and soybeans, are known to increase biodiversity within the appropriate crop rotation and are an important source of import-substituting feed protein. National and regional policy schemes have long tried to support the cultivation of grain legumes. Although many regions in Germany offer favourable conditions for grain legumes, previous subsidy schemes have failed to increase the area under cultivation and farmers report a lack of market incentives. Indeed, the available price data exhibit a substantial share of non-random missing values in weeks when grain legumes were not traded. We analyse these non-price periods using cointegration tests and single-hurdle Tobit models. The results indicate that regional price formation for grain legumes in German regions depends not only on a minimum quantity of the respective legume crop in supply but also on a favourable supra-regional soybean price: Regional grain legume markets are not integrated and show evidence of a fragmented market structure. This may explain why local grain legume value chains have failed to emerge in Germany, despite decades of policy attempts to support these crops.
The chicken gut microbiome in conventional and alternative production systems
(2025) Cheng, Yu-Chieh; Krieger, Margret; Korves, Anna-Maria; Camarinha‑Silva, Amélia
The poultry gut microbiome plays a key role in nutrient digestion, immune function, and overall health. Differences among various farming systems, including conventional, antibiotic-free, free-range, and organic systems, influence microbial composition and function through variations in diet, genetic selection, environmental exposure, and antibiotic use. Conventional systems typically rely on formulated diets and controlled housing conditions, often with routine antimicrobial use. In contrast, organic systems emphasize natural feed ingredients, including roughage, outdoor access, and strict limitations on the use of antibiotics. These divergent practices shape the gut microbiota differently, with organic systems generally associated with greater exposure to environmental microbes and, consequently, greater microbial diversity. However, the implications of this increased diversity for poultry health and performance are complex, as organic systems may also carry a higher risk of pathogen exposure. This review summarizes current findings on the chicken gut microbiome across conventional and alternative production systems (antibiotic-free, free-range, and organic), focusing on microbial diversity, functional potential, and disease resilience. The need for standardized methodologies and consistent nomenclature in microbiome research is also discussed to improve comparability across studies. Understanding how production systems influence the gut microbiota is essential for improving poultry health and productivity while addressing challenges related to antimicrobial resistance and sustainable farming practices.
Effect of liquefaction temperature and enzymatic treatment on bioethanol production from mixed waste baked products
(2025) Almuhammad, Mervat; Kölling, Ralf; Einfalt, Daniel
This study investigates the effect of different liquefaction temperatures (50–70 °C) and four commercial enzyme formulations on glucose release and subsequent ethanol yield, using mixed waste baked products as a substrate. Among the enzymes tested, Amylase GA 500 proved to be superior in the hydrolysis of starch at lower temperatures (50 °C and 55°C). At higher liquefaction temperatures (65 °C and 70°C) all four enzyme preparations showed comparable activity. The highest glucose concentration (205.7 g/L) and the highest ethanol yield (92 g/L) were achieved with Amylase GA 500 at 65 °C. Its superior performance is attributed to the synergistic activity of α-amylase and glucoamylase, which facilitates efficient starch hydrolysis. Crucially, we discovered that the liquefaction temperature profoundly affects fermentation speed independently of the initial glucose concentration or the enzyme preparation used for starch hydrolysis. This novel mechanistic insight suggests that higher temperature treatment either makes an additional factor crucial for yeast fermentation available or depletes/destroys an inhibitor present in the complex waste bakery product matrix. These findings highlight the critical role of temperature and enzyme formulation in optimizing bioethanol production from bakery waste, supporting the development of more sustainable and efficient waste-to-biofuel processes.
Effects of Prosopis juliflora pods on sheep performance and carcass traits, and their methane mitigation potential as assessed in vitro
(2025) Tadesse, Assefa; Titze, Natascha; Rodehutscord, Markus; Melesse, Aberra
This study aimed to assess the effect of partial substitution of concentrate mix (CM) with Prosopis juliflora pod (PJP) on growth performance and carcass traits in sheep, and its potential to reduce methane (CH4) production in vitro. A total of 25 yearling rams with an initial body weight of 15.8±1.53 kg was randomly assigned to five treatment diets. The diets were a control diet (JP0) and JP0 replaced with PJP at the level of 5% (JP5), 10% (JP10), 15% (JP15), and 20% (JP20). Data were collected on feed intake, body weight, and carcass characteristics. Methane production was determined from 24 h in vitro gas production. The substitution of CM with PJP did not affect feed intake, body weight, weight gain, feed efficiency, and carcass traits (p>0.05). The in vitro CH4 production was reduced (p<0.001) in diets containing increased levels of PJP. The metabolizable energy for JP10, JP15 and JP20 diets was 11.9, 11.6 and 11.5 MJ/kg DM, respectively (p>0.05). In conclusion, replacing CM with PJP did not negatively affect growth performance and carcass characteristics and could be used as potential supplement to mitigate methane emissions. Further in vivo studies involving respiration chambers are recommended to investigate the CH4 reduction potential of PJP.
Expression of fibroblast growth factor 23 (FGF23) and αKlotho in two commercial laying hen strains fed with and without dietary mineral P supplements before and after the onset of the laying phase
(2025) Meier, Leonie; Wallauch, Nadine; Feger, Martina; Oster, Michael; Sommerfeld, Vera; Schmucker, Sonja; Wimmers, Klaus; Huber, Korinna; Stefanski, Volker; Rodehutscord, Markus; Föller, Michael
Maintenance of phosphate homeostasis is particularly critical in laying hens for bone formation and calcium mobilization. The supplementation of their feed with mineral phosphate is common although recent research questions the usual levels of supplementation. Phosphate homeostasis is classically regulated by active vitamin D (calcitriol) and parathyroid hormone, whereas fibroblast growth factor 23 (FGF23) and its co-receptor αKlotho are novel factors. FGF23 has emerged as an important disease biomarker and αKlotho as an anti-aging factor in mammals, however, little is known about their role in poultry. Here, we studied FGF23 and αKlotho expression in two commercial laying hen strains under conditions of dietary mineral phosphorus renunciation and sufficient phosphorus supply. Fifteen- and 20-week-old Lohmann Brown-Classic (LB) or LSL-Classic (LSL) hens were fed a standard maize-soybean-based diet containing 0 or 1 g/kg additional mineral phosphorus for 4 weeks. The animals were sacrificed, and gene expression studied in different organs by quantitative real-time PCR and protein expression by western blotting. Statistical correlation with further parameters of mineral metabolism was analyzed by Pearson’s correlation coefficient or Spearman’s Rho. As a result, FGF23 bone expression was significantly lower and hepatic FGF23 expression higher in 24-week-old than in 19-week-old hens. Bone, hepatic, and renal αKlotho expression was significantly higher in older than younger animals. Compared to LB hens, LSL hens exhibited higher hepatic αKlotho irrespective of diet and age. Dietary phosphorus content did not significantly affect FGF23 and αKlotho expression. Bone FGF23 expression was positively and hepatic FGF23 negatively associated with plasma phosphate concentration whereas bone FGF23 expression was negatively and hepatic FGF23 positively associated with plasma calcitriol concentration. To conclude, we uncovered a strong impact of age and strain on FGF23 and αKlotho expression in two high performance laying hen strains, effects possibly associated with initiation of the egg-laying phase. Moreover, the regulation of hepatic FGF23 expression differed from the regulation of bone FGF23 expression. Further studies are needed to elucidate the physiological relevance.
Historic insights and future potential in wheat elaborated using a diverse cultivars collection and extended phenotyping
(2025) El Hassouni, Khaoula; Afzal, Muhammad; Boeven, Philipp H. G.; Dornte, Jost; Koch, Michael; Pfeiffer, Nina; Pfleger, Franz; Rapp, Matthias; Schacht, Johannes; Spiller, Monika; Sielaff, Malte; Tenzer, Stefan; Thorwarth, Patrick; Longin, C. Friedrich H.
Wheat is one of the most important staple crops worldwide. Wheat breeding mainly focused on improving agronomy and techno-functionality for bread or pasta production, but nutrient content is becoming more important to fight malnutrition. We therefore investigated 282 bread wheat cultivars from seven decades of wheat breeding in Central Europe on 63 different traits related to agronomy, quality and nutrients in multiple field environments. Our results showed that wheat breeding has tremendously increased grain yield, resistance against diseases and lodging as well as baking quality across last decades. By contrast, mineral content slightly decreased without selection on it, probably due to its negative correlation with grain yield. The significant genetic variances determined for almost all traits show the potential for further improvement but significant negative correlations among grain yield and baking quality as well as grain yield and mineral content complicate their combined improvement. Thus, compromises in improvement of these traits are necessary to feed a growing global population.
Iron partitioning and photosynthetic performance in Cannabis sativa L. reveal limitations of nanoscale zero-valent iron as a fertilizer
(2025) Büser, Christian; Hartung, Jens; Deurin, Lukas; Graeff-Hönninger, Simone
Iron (Fe) is the fourth most abundant element in the Earth’s crust but remains the third most limiting nutrient for crop productivity due to its low solubility in most soils. The emergence of nanotechnology has introduced nanoscale zero-valent iron (nZVI) as a potential Fe fertilizer with high surface reactivity and improved bioavailability. However, its comparative efficacy relative to conventional chelated Fe sources remains poorly understood. This study investigated Fe partitioning, photosynthetic efficiency, biomass accumulation, and cannabinoid synthesis in Cannabis sativa L. grown hydroponically under Fe-EDTA, nZVI, or Fe-deficient (-Fe) treatments. Total Fe concentrations were markedly reduced in -Fe plants compared with both Fe-EDTA and nZVI treatments. Despite similar root Fe contents between Fe-EDTA and nZVI, only Fe-EDTA facilitated efficient translocation to shoots, while nZVI-derived Fe predominantly accumulated in roots. Consequently, nZVI-treated plants exhibited intermediate photosynthetic performance and water-use efficiency—lower than Fe-EDTA but significantly higher than -Fe. Although Fe translocation differed substantially, inflorescence biomass and cannabinoid yield were comparable between nZVI and Fe-EDTA treatments, both exceeding those of -Fe plants. These results suggest that yield reductions under Fe deficiency arise not solely from Fe scarcity but also from the metabolic costs of Strategy I Fe acquisition, which are partially circumvented by root Fe availability from nZVI. Overall, Fe-EDTA demonstrated superior nutrient use efficiency, whereas nZVI partially alleviated Fe deficiency and revealed distinctive interactions between nanomaterials and plant Fe physiology. This study advances understanding of nZVI as an alternative Fe source in C. sativa and provides new insights into nanoparticle–plant nutrient dynamics.
Limitations of soil-applied non-microbial and microbial biostimulants in enhancing soil P turnover and recycled P fertilizer utilization: A study with and without plants
(2024) Herrmann, Michelle Natalie; Griffin, Lydia Grace; John, Rebecca; Mosquera-Rodríguez, Sergio F.; Nkebiwe, Peteh Mehdi; Chen, Xinping; Yang, Huaiyu; Müller, Torsten
Introduction: Phosphorus recovery from waste streams is a global concern due to open nutrient cycles. However, the reliability and efficiency of recycled P fertilizers are often low. Biostimulants (BS), as a potential enhancer of P availability in soil, could help to overcome current barriers using recycled P fertilizers. For this, a deeper understanding of the influence of BSs on soil P turnover and the interaction of BSs with plants is needed. Methods: We conducted an incubation and a pot trial with maize in which we testednon-microbial (humic acids and plant extracts) and microbial BSs (microbial consortia) in combination with two recycled fertilizers for their impact on soil P turnover, plant available P, and plant growth. Results and discussion: BSs could not stimulate P turnover processes (phosphatase activity, microbial biomass P) and had a minor impact on calcium acetate-lactate extractable P (CAL-P) in the incubation trial. Even though stimulation of microbial P turnover by the microbial consortium and humic acids in combination with the sewage sludge ash could be identified in the plant trial with maize, this was not reflected in the plant performance and soil P turnover processes. Concerning the recycled P fertilizers, the CAL-P content in soil was not a reliable predictor of plant performance with both products resulting in competitive plant growth and P uptake. While this study questions the reliability of BSs, it also highlights the necessity toimprove our understanding and distinguish the mechanisms of P mobilization in soil and the stimulation of plant P acquisition to optimize future usage.
Mapping genes for resilient dairy cows by means of across-breed genome-wide association analysis
(2025) Keßler, Franziska; Zölch, Maximilian; Wellman, Robin; Bennewitz, Jörn
Background: Indicator traits based on variance and autocorrelation of longitudinal data are increasingly used to measure resilience in animal breeding. While these traits show promising heritability and can be routinely collected, their genetic architecture remains poorly understood. We conducted GWAS for three resilience indicators across German Holstein ( n = 2,300), Fleckvieh ( n = 2,330), and Brown Swiss ( n = 1,073) dairy cattle ( Bos Taurus ) populations. The indicators included variance ( ) and autocorrelation ( ) of deviations of observed from predicted daily milk yield and variance of relative daily milk yield ( ). Additionally, we analysed a selection index combining these traits. Prior to GWAS, we examined population structure through multi-dimensional scaling (MDS) and LD patterns, revealing distinct genetic clusters for each breed and similar LD decay patterns. Results: The GWAS results confirmed the polygenic nature of resilience, with multiple genomic regions showing significant associations. Notable signals were detected on BTA5 ( ), BTA14 ( ), BTA2 and BTA8 ( ) for single indicator traits. For selection index resilience, strong suggestive SNPs are located on BTA4 , BTA16 , BTA21 , and BTA27 . Detected regions overlapped with previously reported QTLs for performance, reproduction, longevity and health, providing new insights into the biological pathways underlying dairy cattle resilience. Conclusions: Our findings demonstrate that resilience indicators have a complex genetic architecture with both breed-specific and shared components, supporting their potential use in selective breeding programs while highlighting the importance of careful trait definition.
Microbial inoculants modulate the rhizosphere microbiome, alleviate plant stress responses, and enhance maize growth at field scale
(2025) Francioli, Davide; Kampouris, Ioannis D.; Kuhl-Nagel, Theresa; Babin, Doreen; Sommermann, Loreen; Behr, Jan H.; Chowdhury, Soumitra Paul; Zrenner, Rita; Moradtalab, Narges; Schloter, Michael; Geistlinger, Joerg; Ludewig, Uwe; Neumann, Günter; Smalla, Kornelia; Grosch, Rita
Background: Field inoculation of crops with beneficial microbes is a promising sustainable strategy to enhance plant fitness and nutrient acquisition. However, effectiveness can vary due to environmental factors, microbial competition, and methodological challenges, while their precise modes of action remain uncertain. This underscores the need for further research to optimize inoculation strategies for consistent agricultural benefits. Results: Using a comprehensive, multidisciplinary approach, we investigate the effects of a consortium of beneficial microbes (BMc) ( Pseudomonas sp. RU47, Bacillus atrophaeus ABi03, Trichoderma harzianum OMG16) on maize ( Zea mays cv. Benedictio) through an inoculation experiment conducted within a long-term field trial across intensive and extensive farming practices. Additionally, an unexpected early drought stress emerged as a climatic variable, offering further insight into the effectiveness of the microbial consortium. Our findings demonstrate that BMc root inoculation primarily enhanced plant growth and fitness, particularly by increasing iron uptake, which is crucial for drought adaptation. Inoculated maize plants show improved shoot growth and fitness compared to non-inoculated plants, regardless of farming practices. Specifically, BMc modulate plant hormonal balance, enhance the detoxification of reactive oxygen species, and increase root exudation of iron-chelating metabolites. Amplicon sequencing reveals shifts in rhizosphere bacterial and fungal communities mediated by the consortium. Metagenomic shotgun sequencing indicates enrichment of genes related to antimicrobial lipopeptides and siderophores. Conclusions: Our findings highlight the multifaceted benefits of BMc inoculation on plant fitness, significantly influencing metabolism, stress responses, and the rhizosphere microbiome. These improvements are crucial for advancing sustainable agricultural practices by enhancing plant resilience and productivity.
The non-nutritive sweetener rebaudioside a enhances phage infectivity
(2025) Marongiu, Luigi; Brzozowska, Ewa; Brykała, Jan; Burkard, Markus; Schmidt, Herbert; Szermer-Olearnik, Bożena; Venturelli, Sascha
Non-nutritive sweeteners (NNS) are widely employed in foodstuffs. However, it has become increasingly evident that their consumption is associated with bacterial dysbiosis, which, in turn, is linked to several health conditions, including a higher risk of type 2 diabetes and cancer. Among the NNS, stevia, whose main component is rebaudioside A (rebA), is gaining popularity in the organic food market segment. While the effect of NNS on bacteria has been established, the impact of these sweeteners on bacterial viruses (phages) has been neglected, even though phages are crucial elements in maintaining microbial eubiosis. The present study sought to provide a proof-of-concept of the impact of NNS on phage infectivity by assessing the binding of rebA to phage proteins involved in the infection process of enteropathogenic bacteria, namely the fiber protein gp17 of Yersinia enterocolitica phage φYeO3-12 and the tubular baseplate protein gp31 of Klebsiella pneumoniae phage 32. We employed docking analysis and a panel of in vitro confirmatory tests (microscale thermophoresis, RedStarch ™ depolymerization, adsorption, and lysis rates). Docking analysis indicated that NNS can bind to both fiber and baseplate proteins. Confirmatory assays demonstrated that rebA can bind gp31 and that such binding increased the protein’s enzymatic activity. Moreover, the binding of rebA to gp17 resulted in a decrease in the adsorption rate of the recombinant protein to its host but increased the Yersinia bacteriolysis caused by the whole phage compared to unexposed controls. These results support the hypothesis that NNS can impair phage infectivity, albeit the resulting effect on the microbiome remains to be elucidated.
Occurrence and quantification of porcine hemotrophic mycoplasmas in blood-sucking Stomoxys calcitrans
(2025) Arendt, Mareike; Hoelzle, Katharina; Stadler, Julia; Ritzmann, Mathias; Ade, Julia; Hoelzle, Ludwig E.; Schwarz, Lukas; Rossi, Franca
Hemotrophic mycoplasmas (HMs) are cell wall-less, small and uncultivable pathogens, which can cause infections in pigs with no to severe clinical signs and can contribute to significant economic losses in the pig industry. In addition to the known mechanical transmission routes of HMs (e.g., via blood-contaminated instruments or lesions from ranking fights), transmission to pigs by arthropod vectors such as Stomoxys calcitrans is being discussed. To date, there is scant available data concerning the transmission of HMs by stable flies. The objective of this study is to gain more data concerning the occurrence of HMs in Stomoxys calcitrans . Therefore, quantitative real-time PCR was conducted on different stable fly samples (surface washings and whole flies). We found Mycoplasma ( M. ) suis in 5.2% of crushed flies and 4.2% of fly wash solutions, and M. parvum was detected in 5.2% of flies and 9.4% of fly wash solutions. ‘ Candidatus ( Ca .) M. haemosuis’ was not detected in any sample. The mean bacterial loads were 2.0 × 10 2 M. suis /fly, 9.3 × 10 2 M. suis /fly wash solution and, for M. parvum , 2.4 × 10 3 M. parvum /fly and 2.1 × 10 3 M. parvum /fly wash solution. This molecular occurrence of porcine HMs in blood-sucking flies and reasonable bacterial loads in the two- to three-digit range demonstrate that these flies serve as mechanical vectors in stables and are, therefore, of epidemiological importance.
Pathways for biodiversity enhancement in German agricultural landscapes
(2025) Sponagel, Christian; Thompson, Amibeth; Paetow, Hubertus; Mupepele, Anne‐Christine; Bieling, Claudia; Sommer, Martin; Klein, Alexandra‐Maria; Settele, Josef; Finger, Robert; Huber, Robert; Albert, Christian; Filser, Juliane; Jansen, Florian; Kleemann, Janina; Schreiner, Vera; Lakner, Sebastian
Conserving biodiversity, especially in agricultural landscapes, is a major societal challenge. Broad scientific evidence exists on the impacts of single drivers on biodiversity, such as the intensification of agriculture. However, halting biodiversity decline requires a systemic understanding of the interactions between multiple drivers, which has hardly been achieved so far. Selecting Germany as a case study, the goal of our analysis is (i) to understand how various socio‐economic drivers of biodiversity in agricultural landscapes interact at the national scale, (ii) to identify plausible pathways that most likely will lead to an improvement of biodiversity in agricultural landscapes and (iii) to discuss guiding principles for policy‐making based on the pathways. We applied the expert‐based Cross‐Impact‐Balance (CIB) methodology to the German agri‐food system (target year 2030). Seven descriptors that represent the most relevant socio‐economic drivers of biodiversity (here, we focus on species richness) in agricultural landscapes in Germany were defined. In three workshops with different groups of experts, we assessed all the interactions and impacts between these descriptors. From the workshops, seven overlapping scenarios were identified and aggregated into four main future pathways for enhancing biodiversity in agricultural landscapes. These pathways are: (1) ‘Innovation and stricter legislation’, (2) ‘Major change in protein production and CAP shift’, (3) ‘Major change in protein production and national legislation’ and (4) ‘Major social changes compensate for a lack of innovation in food production’. Socio‐economic drivers interact to varying degrees. Societal values have a strong active influence on the system, e. g. agricultural policy, whereas the orientation and objectives of agriculture, e. g. focus on public goods, are rather passively determined. Conserving biodiversity thus depends upon the evolution of societal values, European and national nature conservation and agricultural policies, innovations in plant and protein production as well as on global commodity markets. A key message for policymakers is that there are generally different, complementary options for achieving the objective of improving biodiversity. This is important when specific drivers such as the CAP cannot be steered in a particular desired direction.
Poultry perfection : comparison of computer vision models to detect and classify poultry products in a production setting
(2025) Einsiedel, Daniel; Vita, Marco; Jox, Dana; Dunnewind, Bertus; Meulendijks, Johan; Krupitzer, Christian
This study explores the use of computer vision, specifically object detection, for quality control in ready-to-eat meat products. We focused on a single process step, labeling products as “good” or “imperfect”. An “imperfect product” constitutes a product that deviates from the norm regarding shape, size, or color (having a hole, missing edges, dark particles, etc.). Imperfect does not mean the product is inedible or a risk to food safety, but it affects the overall product quality. Various object detectors, such as YOLO, including YOLO12, were compared using the mAP50-95 metric. Most models achieved mAP scores over 0.9, with YOLO12 reaching a peak score of 0.9359. The precision and recall curves indicated that the model learned the “imperfect product” class better, most likely due to its higher representation. This underscores the importance of a balanced dataset, which is challenging to achieve in real-world settings. The confusion matrix revealed false positives, suggesting that increasing dataset volume or hyperparameter tuning could help. However, increasing the dataset volume is usually the more difficult path since data acquisition and especially labeling are by far the most time-consuming steps of the whole process. Overall, current models can be applied to quality control tasks with some margin of error. Our experiments show that high-quality, consistently labeled datasets are potentially more important than the choice of the model for achieving good results. The applied hyperparameter tuning on the YOLO12 model did not outperform the default model in this case. Future work could involve training models on a multi-class dataset with hyperparameter optimization. A multi-class dataset could contain more specific classes than just “good” and “imperfect,” making trained models capable of actually predicting specific quality deviations.
Recombinant production of Paenibacillus wynnii β-galactosidase with Komagataella phaffii
(2024) Bechtel, Anna; Seitl, Ines; Pross, Eva; Hetzel, Frank; Keutgen, Mario; Fischer, Lutz
The β-galactosidase from Paenibacillus wynnii (β-gal-Pw) is a promising candidate for lactose hydrolysis in milk and dairy products, as it has a higher affinity for the substrate lactose (low KM value) compared to industrially used β-galactosidases and is not inhibited by the hydrolysis-generated product D-galactose. However, β-gal-Pw must firstly be produced cost-effectively for any potential industrial application. Accordingly, the yeast Komagataella phaffii was chosen to investigate its feasibility to recombinantly produce β-gal-Pw since it is approved for the regulated production of food enzymes. The aim of this study was to find the most suitable way to produce the β-gal-Pw in K. phaffii either extracellularly or intracellularly.ResultsFirstly, 11 different signal peptides were tested for extracellular production of β-gal-Pw by K. phaffii under the control of the constitutive GAP promoter. None of the signal peptides resulted in a secretion of β-gal-Pw, indicating problems within the secretory pathway of this enzyme. Therefore, intracellular β-gal-Pw production was investigated using the GAP or methanol-inducible AOX1 promoter. A four-fold higher volumetric β-galactosidase activity of 7537 ± 66 µkatoNPGal/Lculture was achieved by the K. phaffii clone 27 using the AOX1 promoter in fed-batch bioreactor cultivations, compared to the clone 5 using the GAP promoter. However, a two-fold higher specific productivity of 3.14 ± 0.05 µkatoNPGal/gDCW/h was achieved when using the GAP promoter for β-gal-Pw production compared to the AOX1 promoter. After partial purification, a β-gal-Pw enzyme preparation with a total β-galactosidase activity of 3082 ± 98 µkatoNPGal was obtained from 1 L of recombinant K. phaffii culture (using AOX1 promoter).ConclusionThis study showed that the β-gal-Pw was produced intracellularly by K. phaffii, but the secretion was not achieved with the signal peptides chosen. Nevertheless, a straightforward approach to improve the intracellular β-gal-Pw production with K. phaffii by using either the GAP or AOX1 promoter in bioreactor cultivations was demonstrated, offering insights into alternative production methods for this enzyme.
The role of biodiversity in consumer research on food : a review and research agenda
(2025) Schneider, Deborah; Osieja, Sanja; Herbes, Carsten; Weinrich, Ramona
The move towards sustainable consumption has drawn significant attention from scholars and practitioners alike. Biodiversity is an integral part of environmental sustainability and food security, but it has received little attention in consumer research. Findings are fragmented into how biodiversity as a product attribute affects consumer food choices. Thus, we conducted a systematic literature review on consumer research on biodiversity in the context of food choice. We reviewed 45 papers published between 2014 and March 2025. Our analysis was guided by the TCCM (Theories, Contexts, Characteristics, and Methodology) framework for developing a systematic literature review. We examined how biodiversity was conceptualized and defined within the studies and towards study participants. Our findings show that biodiversity as a product attribute generally has positive effects on consumer attitude, willingness to pay, and product choice. However, knowledge about biodiversity and the inherent trade-offs in product choices remains limited, so consumers cannot realistically factor biodiversity into their decision-making. We find that research has taken a narrow view of biodiversity, qualitative studies are rare, and few efforts have been made to build theoretical perspectives from empirical data. We conclude with a proposed agenda for future research and a tentative definition of biodiversity for social science.
Structure formation in fruit preparations by fruit fermentates produced with exopolysaccharide-forming lactic acid bacteria
(2025) Festini, Silvan; Zipori, Dor; Wallisch, Marc; Weiss, Agnes; Neidhart, Sybille; Schmidt, Herbert; Jekle, Mario
Fruit preparations are intermediate food products that are primarily used in the dairy industry for the production of fruit yogurt or frozen desserts. Typically, they are stabilized by added hydrocolloids like pectins. The objective of this study was to investigate the potential replacement of conventional stabilizers by structure-forming fermentates produced by exopolysaccharides (EPS)-forming lactic acid bacteria (LAB). Peach puree was selected as fermentation matrix. Prior to 72 h of incubation, it was inoculated with either the heterofermentative LAB strain Levilactobacillus brevis TMW 1.2112 or the homofermentative LAB strain Pediococcus parvulus strain LTH 1110, both being known to produce EPS in form of β-D-glucan. The lyophilized fermentates were applied as stabilizers to produce strawberry fruit preparations. Flow curves, viscoelastic behaviour and shear stability were measured to investigate the effect of fermentate incorporation on the rheological properties of the products. A fermentatively induced effect was observed in terms of a 1.3-fold increase in viscosity of strawberry model fruit preparations with 10 % fermentate of Lv. brevis TMW 1.2112 compared to the addition of the same dose of fermentate blank. Further, increasing the fermentate blank dose from 10 % to 15 % resulted in a 2.4-fold viscosity increase of the model fruit preparations. High shear stability was found in all model strawberry fruit preparations. However, fermentation had no clear benefit in terms of viscoelastic behaviour and shear stability of the fruit preparations. Although the fermentatively induced thickening potential was limited, production of viscosity-increasing peach fermentate with minor changes in the sugar and amino acid profiles of the fruit proved to be feasible.
Sulfate enhances metabolic acclimation under drought stress - a comparative study of grapevine and maize
(2025) Lehr, Patrick Pascal; Erban, Alexander; Kopka, Joachim; Zörb, Christian
The importance of sulfate fertilization in plant production has becoming increasingly relevant due to the decline in atmospheric sulfur inputs. Moreover, high-intensity cropping systems are increasingly facing drought scenarios. The role of stomata is crucial during drought stress and is linked to sulfate metabolism. This study investigates the impact of sulfate application on the drought response of grapevine and maize guard cells. Both plant species may serve as crop model for analysing underlying physiological processes in a low fertilizer demanding crop such as grapevine and a high fertilizer demanding crop such as maize. Increased sulfate concentration in leaves was triggered by drought in maize and grapevine, but in grapevine only when additional sulfate was applied. Additional sulfate application improved sulfur availability under drought conditions, which enhanced drought stress response in grapevine and maize. This was characterized by enhanced metabolic acclimation under drought conditions. The effect of sulfate on the drought stress response was markedly diminished in guard cells, indicating enhanced metabolic stability of guard cells against external influences. These results underscore the significance of adequate sulfate supply to crops for optimal drought stress response and suggest that sulfate fertilisation may serve as a potential option to enhance drought acclimation
Systematic selection of best performing mathematical models for in vitro gas production using machine learning across diverse feeds
(2025) Ahmadi, Hamed; Titze, Natascha; Wild, Katharina; Rodehutscord, Markus
In vitro gas production (GP) is commonly used to evaluate ruminant feed, yet its accurate interpretation requires robust mathematical modeling. This study systematically explores a wide array of nonlinear models to explain GP dynamics across various feed types, addressing the question: how can efficient and versatile models that accurately represent GP profiles be identified? We hypothesized that distinct feed types exhibit unique GP characteristics, effectively captured by specific models, and that statistical and machine learning methodologies can streamline model selection. Utilizing a comprehensive dataset derived from 849 unique GP profiles across concentrate feed categories—including cereal and leguminous grains and processed protein feeds—21 candidate models were rigorously evaluated based on their goodness-of-fit metrics, with a particular emphasis on Bayesian Information Criterion (BIC) for model selection. A group of three models—namely Burr XII, Inverse paralogistic, and Log-logistic—consistently emerged as top performers, demonstrating high generalizability and predictive power across feed types. Notably, our analysis indicated that model type significantly influenced GP predictions, surpassing the impact of feed type characteristics. This research establishes a decision-making framework for model selection and sets the stage for further investigations linking in vitro GP parameters to in vivo digestibility, ultimately enhancing ruminant nutrition strategies.

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