Fakultät Naturwissenschaften

Permanent URI for this communityhttps://hohpublica.uni-hohenheim.de/handle/123456789/1

Biologie, Ernährungs-wissenschaften und Lebensmittelwissenschaften sind die Schwerpunkte der Fakultät. Die Forschung befasst sich mit Schlüsselthemen der Life Sciences.

Homepage: https://natur.uni-hohenheim.de/

Browse

Now showing 1 - 20 of 58

Acrocomia aculeata fruits from three regions in Costa Rica: An assessment of biometric parameters, oil content and oil fatty acid composition to evaluate industrial potential
(2020) Alfaro-Solís, Jose David; Montoya-Arroyo, Alexander; Jiménez, Víctor M.; Arnáez-Serrano, Elizabeth; Pérez, Jason; Vetter, Walter; Frank, Jan; Lewandowski, Iris
Due to increased global demand for vegetable oils, diversification of the supply chain with sustainable sources is necessary. Acrocomia aculeata has recently gained attention as a multi-purpose, sustainable crop for oil production. However, the information necessary for effective selection of promising varieties for agricultural production is lacking. The aim of this study was to assess variability in fruit morphology and oil composition of individual Acrocomia aculeata plants growing wild in different climatic regions of Costa Rica. Fruits at the same ripening stage were collected at three locations, and biometric features, oil content, fatty acid composition of oils from kernels and pulp, as well as fiber composition of husks were determined. Biometric parameters showed high variability among the regions assessed. Moreover, oil content and relative proportions of unsaturated fatty acids were higher at the most tropical location, whereas lauric acid content was lowest under these conditions, indicating a potential environmental effect on oil composition. Pulp oil content correlated positively with annual precipitation and relative humidity, but no clear relation to temperature was observed. The oil chemical composition was similar to that reported for Elaeis guineensis, suggesting that Acrocomia aculeata from Costa Rica may be a suitable alternative for industrial applications currently based on African palm oil. Analysis of husks as a coproduct revealed the possibility of obtaining materials with high lignin and low water and ash contents that could be used as a solid bioenergy source. In conclusion, Acrocomia aculeata oil is a promising alternative for industrial applications currently based on African palm oil and byproducts of its oil production could find additional use as a renewable energy source.
Adaptations of maize to low phosphate availability
establishing regulatory networks from large-scale quantitative proteomic profiling
(2022) He, Mingjie; Schulze, Waltraud
Maize (Zea mays) is an important crop in global for human food, animal feed and industrial usage. Suboptimal phosphorus (P) availability is one of the primary constraints for maize growth and productivity (Jianbo Shen et al., 2011; L.pez-Arredondo et al., 2014). Over 70% arable land suffers from P-deficiency, and plants can take up small amounts of P from the soil due to P-fixation. However, over-application of P fertilizer has frequently happened in last decades and resulted in environmental pollution (L.pez- Arredondo et al., 2014). Modern agriculture calls for maintaining productivity while reducing synthetic-P fertilizer inputs and losses, thus, requiring breeding of novel cultivars to increase phosphate use efficiency (PUE) (Balemi and Negisho, 2012; X., Li, Mang, et al., 2021; Mardamootoo et al., 2021). Understanding the regulation of maize to low phosphate(LP)-availability at the molecular level will offer unlimited potential for the development of selection markers and engineering targets in breeding programs. Nowadays, “OMIC” approaches and computational science are developing rapidly. They are advanced tools for investigation of molecular adaptations on a large-scale and in a systemic view. Thereby, the major research task within this thesis is to reveal P-deficiency induced responsive components and regulations at protein level based on proteomic profiles, aiming to provide promising candidate genes/proteins for research on the molecular mechanisms of adaptation to LP-stress, and potentially to provide promising candidate gene/proteins for development of selection markers and engineering targets to obtain desired traits, in the long term goal of improving PUE in novel cultivars. In Chapter 1, we focused on six genotypes (EP1, F2, F142, F160, SF1, SM1) with close genetic background but several contrasting traits to LP-stress, such as PUE (X., Li, Mang, et al., 2021). They were cultured in pot with either sufficient or inefficient P-fertilizer in a climate chamber for one month. The young seedlings were sampled by root and shoot for analysis of multiple traits, transcriptome and proteome. Firstly, we constructed the co-expression network of proteins and transcripts separately using WGCNA method (Langfelder and Horvath, 2008), which predicted potential protein-protein interactions or their co-regulations. Secondly, we categorized proteins/transcripts to modules according to their different coexpression patterns, thus, identified potential determining relationships of modules-traits. Thirdly, we compared the responses between transcripts and proteins, presenting their responses being concordant or dis-concordant. Fourthly, we identified common and genotype-specific P-starvation response modules and biological processes. Finally, we focused on protein kinases, which play roles as regulators, to demonstrated protein kinases-centered network and validated protein interactions between mitogenactivated protein kinase-kinase 1 (MEK1, Zm00001d043609) either with sucrose synthase1 (SH1,Zm00001d045042) or translation elongation factor 1-gamma 3 (eEF1B-γ, Zm00001d046352). MEK1 is a potential genotype-specific regulator via sucrose metabolism and translation elongation process. In Chapter 2, we aimed to adapted an experimental workflow for phosphoproteome analysis in maize, addressing the interference to phosphoproteome quantification by fibers, secondary metabolites and low abundant of phosphorylated proteins. In this manuscript, we described a rapid and universal protocol for both proteome and phosphoproteome analysis that is suitable for cereal crops. The results of phosphoproteome in maize root testing samples showed that proteins within kinase-centered network in Chapter 1 can be largely quantified based on this workflow. It provides a possible way to analyze phosphorylation dynamics to P-starvation responses, it allows further investigation for kinase-centered 1 network in Chapter 1 to identify phosphorylation pairs of “protein kinase – protein substrate”, which will largely expand a view on P-starvation regulations through posttranslational modifications.
AMP-activated protein kinase (AMPK)-dependent regulation of renal transport
(1996) Glosse, Philipp; Föller, Michael
Analyse von Pathogenresistenzmechanismen in Tomate (Solanum lycopersicum L.)
(2008) Gerhardts, Anja; Pfitzner, Artur J. P.
For many organisms plants serve as a source of nutrients and energy, but because of their static location they are exposed to various harmful environmental influences. Due to this factor they have developed complex defence mechanisms e. g. for protection against pathogens. An important aspect of these defence mechanisms is the expression of intrinsic resistance genes (R) that detect pathogenic avirulence gene products (Avr) thereby causing a hypersensitive response (HR) in the infected cells and consequently inhibiting the systemic infection of the plant. In this work the resistance genes Tm-2 and Tm-2² of tomato were isolated, cloned and sequenced. The allelic R genes are members of the CC-NBS-LRR group of resistance genes, which is widely spread in plants, and differ only in four amino acids. This is surprising because using resistance breaking ToMV strains Weber et al. (2004) showed that both resistance gene products interact differently with the movement protein (30 kDa MP = Avr) of the virus. To gain further insight into this phenomenon of different pathogen detection, chimeric exchange constructs (A1 and A2) were designed through restriction in the region between the NBS and the LRR domain. These four constructs were used for transformation of MM tomatoes as well as NN and nn tobacco plants. The expression of the resistance gene constructs in MM an nn lines did not confer the expected resistance to ToMV. Nevertheless in older infected nn transformants a formation of spontaneous necrosis was observed, which indicates a delayed development of HR. One possible explanation could be that the presence of only the resistance gene product is not sufficient to detect the viral movement protein and that other host cellular components are involved in this process (as in the guard hypothesis by Dangl and Jones, 2001). This assumption is supported by our yeast two hybrid interaction experiments which showed that a direct interaction of Tm-2 and 30 kDa MP can be excluded. For the NN transformants differences in functionality of the constructs was observed. While NN/Tm-2 and NN/A2 plants showed extreme resistance to ToMV wild type (ToMV0) and the Tm-2² resistance breaking strain ToMV2², the Tm-2² and A1 constructs conferred less resistance to ToMV0 and the Tm-2 resistance breaking strain ToMV1-2. This finding also supports the assumption that there is a difference in pathogen detection between the two alleles. Furthermore it shows that the detection takes place within the LRR region because the exchange construct that behaves in the same way as the endogenous resistance gene carries the C-terminal LRR domain of this allele. The hydroxycinnamoyl-CoA:tyramine N-(Hydroxycinnamoyl)transferase (THT) was found to be another candidate for transmission of pathogen resistance during HR (Gerhardts, 2003). Our in vivo results show that the products of the THT enzymatic reaction induced during HR does not only have an antimicrobiotic effect on the pathogen (von Roepenack-Lahaye et al., 2003; Newman et al., 2001) but also has an apoptotic effect on the plant cell itself.
Association of Torquetenovirus Viremia with physical frailty and cognitive impairment in three independent European cohorts
(2023) Giacconi, Robertina; Laffon, Blanca; Costa, Solange; Teixeira-Gomes, Armanda; Maggi, Fabrizio; Macera, Lisa; Spezia, Pietro Giorgio; Piacenza, Francesco; Bürkle, Alexander; Moreno-Villanueva, María; Bonassi, Stefano; Valdiglesias, Vanessa; Teixeira, Joao Paulo; Dollé, Martijn E.T.; Rietman, M. Liset; Jansen, Eugène; Grune, Tilman; Gonos, Efstathios S.; Franceschi, Claudio; Capri, Miriam; Weinberger, Birgit; Sikora, Ewa; Stuetz, Wolfgang; Toussaint, Olivier; Debacq-Chainiaux, Florence; Hervonen, Antti; Hurme, Mikko; Slagboom, P. Eline; Schön, Christiane; Bernhardt, Jürgen; Breusing, Nicolle; Pásaro, Eduardo; Maseda, Ana; Lorenzo-López, Laura; Millán-Calenti, José Carlos; Provinciali, Mauro; Malavolta, Marco
Introduction: Immunosenescence and inflammaging have been implicated in the pathophysiology of frailty. Torquetenovirus (TTV), a single-stranded DNA anellovirus, the major component of the human blood virome, shows an increased replication rate with advancing age. An elevated TTV viremia has been associated with an impaired immune function and an increased risk of mortality in the older population. The objective of this study was to analyze the relation between TTV viremia, physical frailty, and cognitive impairment. Methods: TTV viremia was measured in 1,131 nonfrail, 45 physically frail, and 113 cognitively impaired older adults recruited in the MARK-AGE study (overall mean age 64.7 ± 5.9 years), and then the results were checked in two other independent cohorts from Spain and Portugal, including 126 frail, 252 prefrail, and 141 nonfrail individuals (overall mean age: 77.5 ± 8.3 years). Results: TTV viremia ≥4log was associated with physical frailty (OR: 4.69; 95% CI: 2.06–10.67, p < 0.0001) and cognitive impairment (OR: 3.49, 95% CI: 2.14–5.69, p < 0.0001) in the MARK-AGE population. The association between TTV DNA load and frailty status was confirmed in the Spanish cohort, while a slight association with cognitive impairment was observed (OR: 1.33; 95% CI: 1.000–1.773), only in the unadjusted model. No association between TTV load and frailty or cognitive impairment was found in the Portuguese sample, although a negative association between TTV viremia and MMSE score was observed in Spanish and Portuguese females. Conclusions: These findings demonstrate an association between TTV viremia and physical frailty, while the association with cognitive impairment was observed only in the younger population from the MARK-AGE study. Further research is necessary to clarify TTV’s clinical relevance in the onset and progression of frailty and cognitive decline in older individuals.
Bacterial subversion of NLR-mediated immune responses
(2022) Kienes, Ioannis; Johnston, Ella L.; Bitto, Natalie J.; Kaparakis-Liaskos, Maria; Kufer, Thomas A.
Members of the mammalian Nod-like receptor (NLR) protein family are important intracellular sensors for bacteria. Bacteria have evolved under the pressure of detection by host immune sensing systems, leading to adaptive subversion strategies to dampen immune responses for their benefits. These include modification of microbe-associated molecular patterns (MAMPs), interception of innate immune pathways by secreted effector proteins and sophisticated instruction of anti-inflammatory adaptive immune responses. Here, we summarise our current understanding of subversion strategies used by bacterial pathogens to manipulate NLR-mediated responses, focusing on the well-studied members NOD1/2, and the inflammasome forming NLRs NLRC4, and NLRP3. We discuss how bacterial pathogens and their products activate these NLRs to promote inflammation and disease and the range of mechanisms used by bacterial pathogens to evade detection by NLRs and to block or dampen NLR activation to ultimately interfere with the generation of host immunity. Moreover, we discuss how bacteria utilise NLRs to facilitate immunotolerance and persistence in the host and outline how various mechanisms used to attenuate innate immune responses towards bacterial pathogens can also aid the host by reducing immunopathologies. Finally, we describe the therapeutic potential of harnessing immune subversion strategies used by bacteria to treat chronic inflammatory conditions.
The beauty of bacteriophage T4 research: Lindsay W. Black and the T4 head assembly
(2022) Kuhn, Andreas; Thomas, Julie A.
Viruses are biochemically complex structures and mainly consist of folded proteins that contain nucleic acids. Bacteriophage T4 is one of most prominent examples, having a tail structure that contracts during the infection process. Intracellular phage multiplication leads to separate self-directed assembly reactions of proheads, tails and tail fibers. The proheads are packaged with concatemeric DNA produced by tandem replication reactions of the parental DNA molecule. Once DNA packaging is completed, the head is joined with the tail and six long fibers are attached. The mature particles are then released from the cell via lysis, another tightly regulated process. These processes have been studied in molecular detail leading to a fascinating view of the protein-folding dynamics that direct the structural interplay of assembled complexes. Lindsay W. Black dedicated his career to identifying and defining the molecular events required to form the T4 virion. He leaves us with rich insights into the astonishingly precise molecular clockwork that co-ordinates all of the players in T4 assembly, both viral and cellular. Here, we summarize Lindsay’s key research contributions that are certain to stimulate our future science for many years to come.
Changes in the concentration of particular hormones and carbohydrates in apple shoots after "bending" respectively chemical treatments and relationship to the flower induction process
(2005) Boonplod, Nopporn; Bangerth, Fritz
SUMMARY Apples are cultivated commercially throughout the temperate zone. A regular production however does not seem possible because of irregular yields from year to year. Main causes for this are the so called "alternate bearing" behavior which is the result of profuse flowering in one year but few or no flowers in the following year. It is reported that too vigorously growing shoots are part of the reasons for alternate bearing in apple trees. Applications of chemicals or conventional cultural practices, such as bending shoots have been widely used to restrict shoot growth and promote flower induction. However, the physiological mode of action of these methods in FI is still unknown. Phytohormones are thought to be involved in the process of flower induction (FI). In the above experiments, we investigated changes in endogenous hormones, starch and sugar contents after bending upright shoots into a horizontal position and spraying apple trees with the growth regulators Alar plus Ethrel to improve FI. The experiments were carried out during the years 2001 to 2003 at the Experiment Station, of the University of Hohenheim, Germany, whereby the apple cvs. ?Golden Delicious?, ?Boskoop?, ?Elstar? and ?Idared? were used. The apical part of growing shoots and non-growing bourse shoots, beside bark, wood and shoot diffusates were collected. Plant samples were frozen immediately in liquid nitrogen and freeze dried. Phosphate buffer 0.1M, pH 6.2 was used for collecting auxin in the shoot diffusates. All samples were stored at ?20C until extraction and purified, identified and quantified by Radio Immuno Assay (RIA). The results revealed, in general, that shoot bending and spraying with Alar plus Ethrel changed the endogenous hormone concentrations in the apical part of shoots, as well as in wood, bark and shoot exudates of apple trees. The ?Golden Delicious? cultivar and vigorously growing shoots showed clearer tendencies of hormonal changes than the other cvs. and non-growing bourse shoots. Cytokinin concentrations in the apical part of shoots, and in wood and bark increased after both treatments. Contrary to that, GAs and IAA concentrations in the apical part of shoots and in shoot exudates showed the opposite results. Both treatments had no effect on the concentration of ABA. Ethylene production in shoot tips was considerably stimulated by the combined treatment of Ethrel plus Alar probably due to Ethrel being a "synthetic precursor" of ethylene. Considerable variation existed in the mentioned hormonal changes in respect to the year of examination and the cv. under investigation. Time of treatments and in particular climatic conditions were probably the most influential variables. In spite of all this and on the basis of the above results the conclusion can be drawn that higher concentrations of cytokinins and lower concentrations of gibberellins and auxin are favorable for FI. Spraying with Alar plus Ethrel and bending of shoots seemed to decrease the reducing-sugars, as well as sucrose and starch concentrations in growing shoots and their leaves. In non-growing shoots, spraying seemed to reduce starch but to increase reducing-sugars and sucrose concentrations. A correlation between changes in carbohydrate contents (reducing sugar, sucrose and starch) caused by the spraying treatments and FI does not seem to exist. All the observed changes in the carbohydrate concentrations caused by spraying treatments were not particular impressive and did not really support the often published claim that the effect of spraying growth regulators, bending shoots or other cultural practices may mediate their stimulatory effect on FI via a change in carbohydrates. In contrast to that the above observed experimental results rather suggest that hormones are more effectively involved in the flower induction process of fruit trees.
Charakterisierung der Matrixmetalloproteinasen (SlMMP1 & SlMMP2) aus Tomate (Solanum lycopersicum) und ihre Rolle in der pflanzlichen Entwicklung und Pathogeninteraktionen
(2010) Pasule, Christian; Schaller, Andreas
Matrixmetalloproteinases belong to the family of metzincins and are widely distributed in prokaryotic as well as eukaryotic organisms. Mammalian matrixmetalloproteinases function in the formation of peptide hormones, growth factors and receptor proteins and regulate important physiological processes. Little is known about the function of the related plant matrixmetalloproteinases, except for a few enzymes in plants. Their function in tomato plants is still unresolved. However, preliminary data suggest that matrixmetalloproteinases may play essential roles in the regulation of development and pathogen defense in tomato plants. The present study aimed at the elucidation of the function of the tomato matrixmetalloproteinases SlMMP1 and SlMMP2 by purification and biochemical characterization of the recombinant proteins, detailed expression analysis in tomato plants, as well as the phenotypical and molecular analysis of transgenic plants with reduced expression levels for SlMMP1/2 (SlMMP1/2-RNAi). SlMMP1/2 were expressed in E. coli and purified by affinity chromatography. Activity of recombinant MMPs was stimulated by Ca2+-ions. The highest activity was measured for SlMMP1 at pH 6,5 and for SlMMP2 at pH 7. The apparent Km-values for a fluorigenic peptide substrate were 19,5 µM for SlMMP1 and 19,9 µM for SlMMP2, with a catalytic efficiency (kcat/KM) of 0,010 and 0,024 s-1*µM-1 respectively. These data suggest redundant functions for SlMMP1 and SlMMP2. SlMMP1 was found to be expressed in all tested organs and developmental stages with highest expression levels in eight days old seedlings and stems from six weeks old plants. A constitutive expression in leaves from six weeks old plants was not observed for SlMMP2. In eight days old seedlings, SlMMP2 showed higher expression in roots and hypocotyls than in cotyledons. The tissue-specific expression of SlMMP1 and SlMMP2 suggests specific functions and substrates for the two enzymes in different tissues, inspite of their similar biochemical properties. SlMMP1/2 were localised to cell walls from hypocotyls and roots using immunohistochemistry. This confirms the assumed extracellular localisation of the enzymes. Transgenic plants with reduced SlMMP1/2 expression levels exhibit alterations in surface structure leading to necrotic lesions two weeks after germination. The lesions spread over the entire hypocotyl during later stages of development. Cellular organisation was altered in cortical tissues accompanied by cell death events in the epidermis and subepidermal cell layer. These effects spread over leaves during later stages of development. SlMMP1/2-RNAi-plants accumulate massive amounts of phenolic compounds, and exhibit impaired root development with a reduction in overall root length and reduced numbers of primary and secondary lateral roots. Many of the observed effects suggest an involvment of ethylene and a higher ethylene production was in fact confirmed in SlMMP1/2-RNAi-plants. The effects of the loss of SlMMP1/2 on gene expression were analyzd with microarrays in hypocotyls from SlMMP1/2-RNAi-plants. 522 genes were found to be differentially regulated in SlMMP1/2-RNAi-hypocotyls, with 332 up- and 190 downregulated as compared with widtype plants. Genes with roles in plant development, stress, reaction during abiotic and biotic stimuli, and genes with unknown roles in biological processes appeared to be overrepresented among the differentially regulated genes, however, statistically not significantly. Genes with functions in transport were found to be underrepresented in RNAi-plants. Based on the observation that infection with Sclerotinia sclerotiorum led to induction of SlMMP1/2 gene expression, a possible function for the enzymes in pathogen defense was analyzed. A direct involvment of the enzymes in plant defense against the fungus can be excluded, however, because no differences in fungal growth were detected between wildtype and SlMMP1/2-RNAi-plants. Furthermore, it was analyzed if there are differences in resistance against the biotrophic pathogen Xanthomonas campestris pv. vesicatoria (Xcv) between wildtype and SlMMP1/2-RNAi-plants. Bacterial growth was found to be reduced for virulent, avirulent and non-pathogenic bacteria, accompanied by strong necrosis in SlMMP1/2-RNAi-plants. These data suggest a function for SlMMP1/2 in the regulation of non-specific rections against biotic stresses. The results of the present study provide a basis for a more complete understanding of the function of SlMMP1/2 in development and pathogene defense of tomato plants.
Coffee leaf tea from El Salvador: on-site production considering influences of processing on chemical composition
(2022) Steger, Marc C.; Rigling, Marina; Blumenthal, Patrik; Segatz, Valerie; Quintanilla-Belucci, Andrès; Beisel, Julia M.; Rieke-Zapp, Jörg; Schwarz, Steffen; Lachenmeier, Dirk W.; Zhang, Yanyan
The production of coffee leaf tea (Coffea arabica) in El Salvador and the influences of processing steps on non-volatile compounds and volatile aroma-active compounds were investigated. The tea was produced according to the process steps of conventional tea (Camellia sinensis) with the available possibilities on the farm. Influencing factors were the leaf type (old, young, yellow, shoots), processing (blending, cutting, rolling, freezing, steaming), drying (sun drying, oven drying, roasting) and fermentation (wild, yeast, Lactobacillus). Subsequently, the samples were analysed for the maximum levels of caffeine, chlorogenic acid, and epigallocatechin gallate permitted by the European Commission. The caffeine content ranged between 0.37–1.33 g/100 g dry mass (DM), the chlorogenic acid was between not detectable and 9.35 g/100 g DM and epigallocatechin gallate could not be detected at all. Furthermore, water content, essential oil, ash content, total polyphenols, total catechins, organic acids, and trigonelline were determined. Gas chromatography—mass spectrometry—olfactometry and calculation of the odour activity values (OAVs) were carried out to determine the main aroma-active compounds, which are β-ionone (honey-like, OAV 132-927), decanal (citrus-like, floral, OAV 14-301), α-ionone (floral, OAV 30-100), (E,Z)-2,6-nonadienal (cucumber-like, OAV 18-256), 2,4-nonadienal (melon-like, OAV 2-18), octanal (fruity, OAV 7-23), (E)-2 nonenal (citrus-like, OAV 1-11), hexanal (grassy, OAV 1-10), and 4-heptenal (green, OAV 1-9). The data obtained in this study may help to adjust process parameters directly to consumer preferences and allow coffee farmers to earn an extra income from this by-product.
Combined effects of drought and soil fertility on the synthesis of vitamins in green leafy vegetables
(2023) Park, Taewan; Fischer, Sahrah; Lambert, Christine; Hilger, Thomas; Jordan, Irmgard; Cadisch, Georg
Green leafy vegetables, such as Vigna unguiculata, Brassica oleraceae, and Solanum scabrum, are important sources of vitamins A, B1, and C. Although vitamin deficiencies considerably affect human health, not much is known about the effects of changing soil and climate conditions on vegetable vitamin concentrations. The effects of high or low soil fertility and three drought intensities (75%, 50%, and 25% pot capacity) on three plant species were analysed (n = 48 pots) in a greenhouse trial. The fresh yield was reduced in all the vegetables as a result of lower soil fertility during a severe drought. The vitamin concentrations increased with increasing drought stress in some species. Regardless, the total vitamin yields showed a net decrease due to the significant biomass loss. Changes in vitamin concentrations as a result of a degrading environment and increasing climate change events are an important factor to be considered for food composition calculations and nutrient balances, particularly due to the consequences on human health, and should therefore be considered in agricultural trials.
Complex imprint of solar variability on tree rings
(2020) Land, Alexander; Kromer, Bernd; Remmele, Sabine; Brehm, Nicolas; Wacker, Lukas
Many studies have investigated the role of solar variability in Holocene climate. Beyond sunspot observations, solar activity can be reconstructed from 14C in tree rings. Due to the lack of sub-decadal resolution of 14C records, these studies focused on long-term processes. In this study, we use an annually-resolved 14C record to examine solar variability (e.g. 11-year Schwabe solar cycle) and its connection to European seasonal climate inferred from tree-ring records during the entire past millennium with spectral and wavelet techniques. The 11-year Schwabe solar cycle shows a significant impact in European moisture- and temperature-sensitive tree-ring records. Complex ’top-down’/‘bottom-up’ effects in the strato-tropoatmospheric system are assumed to affect European spring and summer climate with a temporal-shift as evident from observed changes in phase behavior. Significant evidence is also found for the ∼60- and ∼90-year band during the first half of the past millennium.
Composite flour from Indonesian local food resources to develop cereal/tuber nut/bean-based ready-to-use supplementary foods for prevention and rehabilitation of moderate acute malnutrition in children
(2021) Fetriyuna, Fetriyuna; Purwestri, Ratna Chrismiari; Susandy, May; Köhler, Realm; Jati, Ignasius Radix A. P.; Wirawan, Nia Novita; Biesalski, Hans-Konrad
Undernourishment is a threat to human health. The prevalence of undernourishment remains alarming, especially among children under five years old in many countries, including Indonesia. Nowadays, the handling of undernourishment has shifted to treatment outside the hospital, utilizing local nutrient-rich foods. At the national level, the utilization of local food resources is a part of the promotion of dietary diversification and the bioeconomy. Ready-to-use supplementary food (RUSF) refers to supplementary foods aimed at improving the nutrition of moderate acute malnutrition (MAM) children under five years old. RUSF biscuit recipes were made using local food resources available in Banten province, Indonesia. To optimize the nutritional profile of the developed RUSF, taro/talas banten were mixed with ground-nut/peanut (Arachis hypogaea L.) and mungbean (Vigna radiata) as protein and lipid sources and red rice (Oryza longistaminata) and maize (Zea mays) as carbohydrate sources, and enriched by the local banana Nangka (Musa textilia). Two formulations were selected for the pilot testing, namely the taro-peanut and taro-peanut/mungbean RUSF biscuits, made from taro Banten, cereal, peanut and/or mungbean, and local banana. The RUSF biscuit showed promising results, presenting a high level of acceptance and a macronutrient composition that meets the standards for MAM children. However, the RUSF biscuits should be fortified with micronutrient premix to fulfill the dietary requirement for the MAM children. The results of this study provide further development opportunities.
Demethoxycurcumin and Bisdemethoxycurcumin are more bioavailable than Curcumin: A meta-analysis of randomized cross-over trials in healthy umans and an In Vitro mechanistic exploration
(2023) Desmarchelier, Charles; Sus, Nadine; Marconot, Grégory; Gillet, Guillian; Resseguier, Noémie; Frank, Jan
Background: Curcuminoids are secondary plant metabolites found in turmeric and many dietary supplements. They usually consist of a mixture of curcumin (CUR), demethoxycurcumin (dCUR) and bisdemethoxycurcumin (bdCUR). CUR, the main curcuminoid, has been intensely investigated for its putative effects against, e.g., inflammation, oxidative stress and cancer. However, CUR displays very poor bioavailability. We have previously shown that, when brought by turmeric, dCUR and bdCUR, which can also exert health effects, display greater in vitro bioaccessibility than CUR (PMID: 37073511). However, their bioavailability relative to that of CUR has not been thoroughly investigated. Objective: We aimed to compare the bioavailability of dCUR and bdCUR to that of CUR in a meta-analysis of clinical trials in healthy humans and to compare their in vitro bioaccessibility and enterocyte uptake efficiency. Methods and Results: Studies published until 2022 were searched for using Medline and Scopus. The included studies were randomized trials that measured the bioavailability of CUR, dCUR and bdCUR in healthy participants. Estimates were calculated using a random-effects model. Fifteen trials were included in the study, representing a total of 50 interventions, i.e., each trial investigated several curcuminoid formulations, in 762 participants. The relative bioavailabilities were calculated using the inverse variance method. dCUR was 2.32 (95% CI:1.70, 3.13) times more bioavailable than CUR, while bdCUR was 2.57 (95% CI: 1.58, 4.16) times more bioavailable than CUR, with some heterogeneity across the formulations used. Using an in vitro gastro-intestinal digestion model with pure curcuminoids, we showed that dCUR solubilization efficiency was 4.8 and 5.3 times higher than that of CUR and bdCUR, respectively (p < 0.001), while its micellization efficiency was 10.3 and 5.1 times higher than that of CUR and bdCUR, respectively (p < 0.001). Conclusions: bdCUR and dCUR display greater bioavailability in humans compared to CUR. A subgroup analysis by formulation is undergoing investigation and will be presented. For dCUR, this difference is partly explained by higher in vitro bioaccessibility. Uptake efficiency measurements of pure curcuminoids and of curcuminoids from in vitro digestion fluids are undergoing investigation and will be presented. bdCUR and dCUR might therefore represent relevant alternatives to CUR for the systematic delivery of curcuminoids.
Detection and molecular characterization of canine babesiosis causative agent Babesia canis in naturally infected dogs in the Dobrogea area (Southeastern Romania)
(2023) Ionita, Mariana; Leica, Laurentiu; Wassermann, Marion; Mitrea, Emanuel; Nicorescu, Isabela Madalina; Mitrea, Ioan Liviu
Canine babesiosis is an emerging tick-borne disease of major veterinary concern in Europe. Its prevalence has increased in the last two decades and is spreading rapidly toward the north. The aim of this study was to investigate the genetic diversity of Babesia spp. strains isolated from naturally infected dogs in a tick-endemic area (Dobrogea) in southeastern Romania. For this purpose, a total of twenty-three samples from dogs diagnosed with various clinical forms of babesiosis, evaluated by means of clinical history, physical examination, and hematological tests, were subjected to a molecular investigation using PCR, sequencing analysis, and genetic characterization. A microscopic examination of thin Diff-quick-stained blood smears revealed large intra-erythrocytic Babesia piroplasms in all dogs. The PCR and sequencing analysis results indicated the presence of Babesia canis in 22 dogs (95.7%) and Babesia vogeli in 1 dog (4.3%). Among the B. canis isolates, two genotypes were distinguished based on two nucleotide substitutions (GA→AG) observed in the 18S rRNA gene sequences (at positions 609 and 610), with the AG genotype predominating (54.5% of samples), while the GA variant was identified in 9.1% of samples. In the remaining isolates (36.4%), both variants were identified. The B. vogeli-positive dog also tested positive for antibodies against Ehrlichia canis and displayed severe disease. This study reports, for the first time, the presence of genetically heterogenic B. canis strains in dogs with clinical babesiosis in Romania. These findings provide a basis for future studies on the relationship between the genetic structure of the causative agents of canine babesiosis in Romania and the course of the disease.
Detection of bacterial membrane vesicles by NOD-like receptors
(1996) Johnston, Ella L.; Heras, Begoña; Kufer, Thomas A.; Kaparakis-Liaskos, Maria
dmrt2 and myf5 link early somitogenesis to left-right axis determination in Xenopus laevis
(2022) Tingler, Melanie; Brugger, Amelie; Feistel, Kerstin; Schweickert, Axel
The vertebrate left-right axis is specified during neurulation by events occurring in a transient ciliated epithelium termed left-right organizer (LRO), which is made up of two distinct cell types. In the axial midline, central LRO (cLRO) cells project motile monocilia and generate a leftward fluid flow, which represents the mechanism of symmetry breakage. This directional fluid flow is perceived by laterally positioned sensory LRO (sLRO) cells, which harbor non-motile cilia. In sLRO cells on the left side, flow-induced signaling triggers post-transcriptional repression of the multi-pathway antagonist dand5. Subsequently, the co-expressed Tgf-β growth factor Nodal1 is released from Dand5-mediated repression to induce left-sided gene expression. Interestingly, Xenopus sLRO cells have somitic fate, suggesting a connection between LR determination and somitogenesis. Here, we show that doublesex and mab3-related transcription factor 2 (Dmrt2), known to be involved in vertebrate somitogenesis, is required for LRO ciliogenesis and sLRO specification. In dmrt2 morphants, misexpression of the myogenic transcription factors tbx6 and myf5 at early gastrula stages preceded the misspecification of sLRO cells at neurula stages. myf5 morphant tadpoles also showed LR defects due to a failure of sLRO development. The gain of myf5 function reintroduced sLRO cells in dmrt2 morphants, demonstrating that paraxial patterning and somitogenesis are functionally linked to LR axis formation in Xenopus.
Editorial: the long road to building a head: smooth travels and accidents on the journey from patterning via morphogenesis to phenotype
(2022) Feistel, Kerstin; Hammes, Annette; Sela-Donenfeld, Dalit
Effects of feeding diets without mineral P supplement on intestinal phytate degradation, blood concentrations of Ca and P, and excretion of Ca and P in two laying hen strains before and after onset of laying activity
(2024) Sommerfeld, Vera; Bennewitz, Jörn; Camarinha-Silva, Amélia; Feger, Martina; Föller, Michael; Huber, Korinna; Oster, Michael; Ponsuksili, Siriluck; Schmucker, Sonja; Seifert, Jana; Stefanski, Volker; Wimmers, Klaus; Rodehutscord, Markus
The objective of this study was to characterize intestinal phytate degradation and mineral utilization by 2 laying hen strains before and after the onset of egg laying using diets without or with a mineral phosphorus (P) supplement. One offspring of 10 roosters per strain (Lohmann Brown-classic [LB] and Lohmann LSL-classic [LSL]) was sacrificed before (wk 19) and after (wk 24) the onset of egg-laying activity and following 4 wk placement in a metabolic unit. Diets were corn-soybean meal-based and without supplemented P (P-) or with 1 g/kg supplemented P (P+) from monocalcium phosphate. In wk 19 and 24, the blood plasma and digesta of duodenum+jejunum and distal ileum were collected. The concentration of P in blood plasma was higher in hens fed P+ than P- (P < 0.001). In duodenum + jejunum and ileum content, the concentrations of InsP6, Ins(1,2,4,5,6)P5 and Ins(1,2,3,4,5)P5 were lower in P- than in P+ (P ≤ 0.009). In duodenum+jejunum, the concentrations of InsP6, Ins(1,2,4,5,6)P5 and Ins(1,2,3,4,5)P5 were lower in wk 24 than 19 and lower in LSL than LB hens (P < 0.001). The concentration of myo-inositol (MI) in duodenum + jejunum content was lower in wk 19 than 24 (P < 0.001). Following a 4-d total excreta collection, the retained amount of P was higher in P+ than P- (P < 0.001). Phosphorus retention was lower in LB hens fed P- than in other treatments (P × strain: P = 0.039). In the jejunal tissue, some genes related to intracellular InsP metabolism were higher expressed in LB than LSL hens. The renunciation of mineral P increased endogenous phytate degradation, but more P was retained with supplemented P. Differences in endogenous phytate degradation between the periods before and after the onset of egg laying might be attributed to different Ca concentrations in intestinal digesta caused by different Ca needs in both periods.
Effects of myo-inositol supplementation in the diet on myo-inositol concentrations in the intestine, blood, eggs, and excreta of laying hens
(2025) Sommerfeld, Vera; Hanauska, Anna; Huber, Korinna; Bennewitz, Jörn; Camarinha-Silva, Amélia; Feger, Martina; Föller, Michael; Oster, Michael; Ponsuksili, Siriluck; Schmucker, Sonja; Seifert, Jana; Stefanski, Volker; Wimmers, Klaus; Rodehutscord, Markus
The objectives of this study were to investigate whether an increased dietary myo-inositol (MI) supply translates into changes in MI concentrations and endogenous mucosal phosphatase activities in the intestine of laying hens and whether different laying hen strains respond differently to MI supplementation. The diets were corn–soybean meal-based and supplemented without (MI0) or with 1 (MI1), 2 (MI2), or 3 (MI3) g MI/kg feed. Ten hens per strain (Lohmann Brown-classic (LB) and Lohmann LSL-classic (LSL)) and diet were sacrificed at the age of 30 wk following a 4-wk stay in a metabolic unit. The blood plasma, digesta of the duodenum+jejunum and distal ileum, mucosa of the duodenum, and eggs were collected at wk 30. The concentration of MI in the blood plasma was increased by MI supplementation (P < 0.001); however, that of MI3 did not further increase compared with MI2. The concentration of MI in the duodenum+jejunum and ileum increased steadily (P < 0.001). The MI concentration in the duodenum+jejunum was higher in LB than in LSL hens (P = 0.017). The MI concentration in egg yolk was increased by MI supplementation (P < 0.001) and was higher in LB than in LSL hens (P = 0.015). Strain or diet did not affect mucosal phosphatase activity. Myo-inositol flow at the terminal ileum and postileal disappearance increased with each increment in MI supplementation (P < 0.001) and was higher in LB than in LSL hens (P ≤ 0.041). Regression analysis indicated that, on average, 84% of supplemented MI was retained in the body or metabolized and excreted in a different form. Based on the measured MI concentrations in the blood and eggs, dietary MI was not completely absorbed in the small intestine and, to a different extent, in the two laying hen strains. A higher dietary MI supply was followed by higher intestinal absorption or metabolism by microorganisms. The fate of supplemented MI and its relevance to birds warrant further research.

Browse

Browsing Fakultät Naturwissenschaften by Classification "630"