| 1. |
- Albers, Eva, 1966, et al.
(författare)
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Cellular response in fresh water microalgae to polluting compounds of flue gas when used as carbon source
- 2012
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Ingår i: 15th Workshop of International Study Group for Systems Biology (ISGSB), September 25-28, Ameland, The Netherlands.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Attention has lately been given to the use of microalgae as provider of valuable biomass or as production organism. To be able to use algae in industrial production, especially of biofuels, the cultivation procedures need to be improved in terms of efficiency and minimization of production costs. To reach these goals understanding of both process conditions as well as biological response to such conditions is needed for optimization of algal cultivation. Carbon dioxide, the carbon source during phototrophic growth, should be provided at high levels to result in the high biomass concentrations needed for a feasible production. Suitable high-level sources of CO2 are flue gases from industrial activities, which when used for algal cultivation will be a way of carbon capture reducing CO2 emissions. However, flue gases contain additional components that may affect cellular activity negatively. The aim of this research is to understand the physiological behavior of microalgae in industrial conditions to be able to optimize cellular performance. This initial project was launched to provide basic information about response of several types of microalgae that could grow in fresh water conditions to the main gaseous pollutants in flue gas, NO and SO2. This knowledge would guide the selection for a deeper characterization of effect-response relations and control of metabolism in algae in response to industrial conditions. Ten strains of fresh water species and one marine were selected based on reported fast growth and interesting composition such as high levels of lipids. The algae were screened for growth and cellular composition in cultivations with fresh water mineral medium. Artificially produced flue gas, mimicking effluents of pulp mills, consisting of 15% CO2 with 100 ppm NO and 10 ppm SO2 included for the last period of the cultivations was bubbled into the cultures. All strains tested were able to grow and two Scenedesmus strains, an isolated strain from a nearby lake, Chorella protothecoides and Chlamydomonas reinhardtii exhibited the highest specific growth rates. The highest levels of cellular macromolecules were found in Chlorella emersonii (45% carbohydrates), Nannochloropsis salina and the local isolate (65% proteins), and Botrycoccus braunii (57% lipids). It can be concluded that all strains tested were able to grow in cultures with flue gas as carbon source, also the marine species Nannochloropsis salina, and that the gaseous components decrease pH which needs to be monitored carefully to avoid that large drops in pH inhibit algal growth.
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| 2. |
- Albers, Eva, 1966, et al.
(författare)
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Influence of flue gas mimicking effluents of paper mills on growth and cellular composition of fresh water species of microalgae
- 2012
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Ingår i: 9th European Workshop on Biotechnology of Microalgae, 4-5 June, Nuthetal, Germany.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- To be able to use algae in industrial production, especially of biofuels, the cultivation procedures need to be improved in terms of efficiency and minimization of production costs. One important factor is to reach as high biomass concentrations as possible e.g. by using high levels of carbon dioxide provided by flue gas. The aim of this project was to study the influence of flue gas simulated to mimic effluents of pulp mills on growth and cellular composition of microalgae. Ten strains of fresh water species and one marine were selected based on reported fast growth and interesting composition such as high levels of lipids. The algae were screened in cultivations with fresh water mineral medium and artificially produced flue gas bubbled into the cultures consisting of 15% CO2 with 100 ppm NO and 10 ppm SO2 included for the last period of the cultivations. All strains tested were able to grow and two Scenedesmus strains, an isolated strain from a nearby lake, Chorella protothecoides and Chlamydomonas reinhardtii exhibited the highest specific growth rates. The highest levels of cellular macromolecules were found in Chlorella emersonii (45% of carbohydrates), Nannochloropsis salina and the local isolate (65% of proteins), and Botrycoccus braunii (57% of lipids). It can be concluded that all strains tested were able to grow in cultures with flue gas as carbon source, also the marine species Nannochloropsis salina, and that the gaseous components decrease pH which needs to be monitored carefully to avoid that large drops in pH inhibit algal growth.
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| 3. |
- Engström, Niklas, 1985, et al.
(författare)
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Development of celiac-safe foods: prevention of transglutaminase 2 (TG2) deamidation of gluten in healthy non-celiac volunteers
- 2024
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Ingår i: Frontiers in Nutrition. - 2296-861X. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Clinical trial registration: In celiac disease, intestinal transglutaminase (TG2) produces immunogenic peptides by deamidation of gluten proteins. These products drive the celiac immune response. We have previously identified an interaction between gliadin and a food additive, E304i, which prevents gliadin processing (both deamidation and transamidation) by TG2, in vitro. In this study, we investigated if E304i could prevent TG2 processing of gluten in flours and if the effect was evident after simulated gastrointestinal digestion. We also confirmed the outcome in vivo in a human cross-over intervention study in healthy non-celiac participants. TG2 transamidation experiments (in vitro) of digested wheat and rye flours supplemented with E304i at 30 mg/g indicated full prevention of TG2 processing. In the intervention study, participant serum levels of deamidated gliadin peptides (dGDPs) increased after the intake of reference wheat rolls (80 g per day for a week; 41% ± 4% compared to washout), while the intake of the intervention E304i/zinc sulfate wheat rolls generated a modest response (80 g per day for a week; 8 ± 10% of control). The difference between the groups (32.8 ± 15.6%) was significant (p = 0.00003, n = 9), confirming that E304i /zinc addition to wheat rolls prevented TG2 deamidation of gluten. In conclusion, this study shows that E304i /zinc addition to wheat rolls prevents TG2 deamidation of gluten in non-celiac participants. clinicaltrials.gov, identifier (NCT06005376).
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| 4. |
- Engström, Niklas, 1985, et al.
(författare)
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Development of celiac-safe foods: prevention of transglutaminase 2 (TG2) deamidation of gluten in healthy non-celiac volunteers
- 2024
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Ingår i: FRONTIERS IN NUTRITION. - 2296-861X. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- In celiac disease, intestinal transglutaminase (TG2) produces immunogenic peptides by deamidation of gluten proteins. These products drive the celiac immune response. We have previously identified an interaction between gliadin and a food additive, E304i, which prevents gliadin processing (both deamidation and transamidation) by TG2, in vitro. In this study, we investigated if E304i could prevent TG2 processing of gluten in flours and if the effect was evident after simulated gastrointestinal digestion. We also confirmed the outcome in vivo in a human cross-over intervention study in healthy non-celiac participants. TG2 transamidation experiments (in vitro) of digested wheat and rye flours supplemented with E304i at 30 mg/g indicated full prevention of TG2 processing. In the intervention study, participant serum levels of deamidated gliadin peptides (dGDPs) increased after the intake of reference wheat rolls (80 g per day for a week; 41% +/- 4% compared to washout), while the intake of the intervention E304i/zinc sulfate wheat rolls generated a modest response (80 g per day for a week; 8 +/- 10% of control). The difference between the groups (32.8 +/- 15.6%) was significant (p = 0.00003, n = 9), confirming that E304i /zinc addition to wheat rolls prevented TG2 deamidation of gluten. In conclusion, this study shows that E304i /zinc addition to wheat rolls prevents TG2 deamidation of gluten in non-celiac participants.Clinical trial registration clinicaltrials.gov, identifier (NCT06005376).
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| 5. |
- Engström, Niklas, 1985, et al.
(författare)
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Sourdough fermentation of wheat flour does not prevent the interaction of transglutaminase 2 with α2-gliadin or gluten.
- 2015
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Ingår i: Nutrients. - : MDPI AG. - 2072-6643 .- 2072-6643. ; 7:4, s. 2134 - 2144
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Tidskriftsartikel (refereegranskat)abstract
- The enzyme transglutaminase 2 (TG2) plays a crucial role in the initiation of celiac disease by catalyzing the deamidation of gluten peptides. In susceptible individuals, the deamidated peptides initiate an immune response leading to celiac disease. Several studies have addressed lactic fermentation plus addition of enzymes as a means to degrade gluten in order to prevent adverse response in celiacs. Processing for complete gluten degradation is often harsh and is not likely to yield products that are of comparable characteristics as their gluten-containing counterparts. We are concerned that incomplete degradation of gluten may have adverse effects because it leads to more available TG2-binding sites on gluten peptides. Therefore, we have investigated how lactic acid fermentation affects the potential binding of TG2 to gluten protein in wheat flour by means of estimating TG2-mediated transamidation in addition to measuring the available TG2-binding motif QLP, in α2-gliadin. We show that lactic fermentation of wheat flour, as slurry or as part of sourdough bread, did not decrease the TG2-mediated transamidation, in the presence of a primary amine, to an efficient level (73%–102% of unfermented flour). Nor did the lactic fermentation decrease the available TG2 binding motif QLP in α2-gliadin to a sufficient extent in sourdough bread (73%–122% of unfermented control) to be useful for celiac safe food.
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| 6. |
- Engström, Niklas, 1985
(författare)
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Toward celiac-safe foods - Investigation of the interaction between transglutaminase 2 and gluten
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Celiac disease, a chronic autoimmune enteropathy, may develop in genetically predisposed individuals upon ingestion of gluten proteins found in wheat, barley, and rye. Overall prevalence of celiac disease is increasing and it currently affects around 1% of the population. The types and severity of symptoms of celiac disease show high variability, leading to many sufferers remaining undiagnosed. The only available treatment is to follow a strict gluten-free diet, but gluten-free alternatives are less available, more expensive, and often have lower nutritional and sensorial quality. This thesis work examined the interactions between the intestinal enzyme transglutaminase 2 and gluten peptides. Transglutaminase 2 plays a significant role in disease initiation and progression, and is the main autoimmune target in developed celiac disease. A method for measuring the interaction between transglutaminase 2 and gluten was developed and tested in studies on sourdough fermentation of wheat flour and bread. Transglutaminase 2-mediated transamidation of gluten was assayed and the extent of available binding motifs for transglutaminase 2 in α2-gliadin, considered the most immunogenic part of gluten, was assessed using an ELISA-based method. The results showed that lactic acid fermentation, which is not specifically tailored to degrade gluten, cannot sufficiently prevent transglutaminase 2 interaction with gluten or decrease the extent of available binding motifs for transglutaminase 2 on α2-gliadin. In studies investigating the possibility to block specific binding motifs for transglutaminase 2 on gluten peptides, using molecules suitable as food additives, binding to α2-gliadin was computationally simulated and promising candidates were identified. These candidates were analyzed in vitro for the ability to prevent transglutaminase 2-mediated transamidation and deamidation of gliadin. Ascorbyl palmitate was found to interact with α2-gliadin in computer simulations and effectively reduced gliadin interaction with transglutaminase 2 in vitro . The cytotoxicity profile of ascorbyl palmitate, in combination with gliadin, was evaluated in Caco-2 cell cultures by determining cell survival, direct cytotoxicity, inflammatory mediators, and cell layer integrity, and no negative effects were found. In ancillary studies of human ileostomy contents after ingestion of raw and extruded gluten-containing products, degradation products of α-gliadin were identified and the effect of extrusion on digestion was investigated. Preliminary results indicate that protein digestibility was decreased after intake of the extruded product, but the effect on α-gliadin digestion needs further evaluation. However, the majority of α-gliadin seems to be undigested after in vivo digestion in both products. The interaction between transglutaminase 2 and gluten is crucial for celiac disease and in this thesis work, several strategies for preventing this have been explored. Ascorbyl palmitate has been shown to effectively prevent this interaction in vitro and is thus a promising candidate for creating cereal-based foods potentially safe for celiacs.
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| 7. |
- Engström, Niklas, 1985, et al.
(författare)
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Towards Celiac-safe foods: Decreasing the affinity of transglutaminase 2 for gliadin by addition of ascorbyl palmitate and ZnCl2 as detoxifiers
- 2017
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322 .- 2045-2322. ; 7:77
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Tidskriftsartikel (refereegranskat)abstract
- Initiation of celiac disease is triggered in the gastrointestinal tract by transglutaminase 2 (TG2) assisted deamidation of gluten peptides. Deamidation is a side-reaction to transamidation and occurs if primary amines are absent. In contrast to deamidation, transamidation does not trigger an immune response. The aim of the study was to identify a suitable food additive that interacts with TG2 binding motives in gluten-derived peptides to prevent deamidation/transamidation. Homology modelling of alpha 2-gliadin and computational screening of compounds for their binding affinity to a common TG2 binding motive (P) QLP were done by using computational approaches followed by experimental testing of TG2 activity. A database containing 1174 potential food grade ligands was screened against the model of alpha 2-gliadin (27 out of 33 aa). Out of the five best ligands, ascorbyl palmitate, was observed to decrease TG2 transamidation of gliadin by 82% +/- 2%. To completely silence the transamidation, we added zinc chloride (ZnCl2), and thereby reached a 99% +/- 1% inhibition of TG2 activity. In addition, we conducted a pilot experiment in which ascorbyl palmitate was observed to decrease TG2 deamidation of gliadin completely. We propose ascorbyl palmitate in combination with ZnCl2 with the future perspective to become an additive in celiac-safe foods.
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| 8. |
- Ofearghail, Fionn, 1994, et al.
(författare)
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A LCMS Metabolomic Workflow to Investigate Metabolic Patterns in Human Intestinal Cells Exposed to Hydrolyzed Crab Waste Materials
- 2021
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Ingår i: Frontiers in Bioengineering and Biotechnology. - : Frontiers Media SA. - 2296-4185. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- We have developed a LCMS metabolomic workflow to investigate metabolic patterns from human intestinal cells treated with simulated gastrointestinal-digested hydrolyzed crab waste materials. This workflow facilitates smart and reproducible comparisons of cell cultures exposed to different treatments. In this case the variable was the hydrolysis methods, also accounting for the GI digestion giving an output of direct correlation between cellular metabolic patterns caused by the treatments. In addition, we used the output from this workflow to select treatments for further evaluation of the Caco-2 cell response in terms of tentative anti-inflammatory activity in the hopes to find value in the crab waste materials to be used for food products. As hypothesized, the treatment identified to change the cellular metabolomic pattern most readily, was also found to cause the greatest effect in the cells, although the response was pro-inflammatory rather than anti-inflammatory, it proves that changes in cellular metabolic patterns are useful predictors of bioactivity. We conclude that the developed workflow allows for cost effective, rapid sample preparation as well as accurate and repeatable LCMS analysis and introduces a data pipeline specifically for probe the novel metabolite patterns created as a means to assess the performing treatments.
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| 9. |
- Sandberg, Ann-Sofie, 1951, et al.
(författare)
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Iron Supplements Containing Lactobacillus plantarum 299v Increase Ferric Iron and Up-regulate the Ferric Reductase DCYTB in Human Caco-2/HT29 MTX Co-Cultures
- 2018
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Ingår i: Nutrients. - : MDPI AG. - 2072-6643 .- 2072-6643. ; 10:Issue 12
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Tidskriftsartikel (refereegranskat)abstract
- Several human interventions have indicated that Lactobacillus plantarum 299v (L. plantarum 299v) increases intestinal iron absorption. The aim of the present study was to investigate possible effects of L. plantarum 299v on the mechanisms of iron absorption on the cellular level. We have previously shown that lactic fermentation of vegetables increased iron absorption in humans. It was revealed that the level of ferric iron [Fe (H2O)5]2+ was increased after fermentation. Therefore, we used voltammetry to measure the oxidation state of iron in simulated gastrointestinal digested oat and mango drinks and capsule meals containing L. plantarum 299v. We also exposed human intestinal co-cultures of enterocytes and goblet cells (Caco-2/HT29 MTX) to the supplements in order to study the effect on proteins possibly involved (MUC5AC, DCYTB, DMT1, and ferritin). We detected an increase in ferric iron in the digested meals and drinks containing L. plantarum 299v. In the intestinal cell model, we observed that the ferric reductase DCYTB increased in the presence of L. plantarum 299v, while the production of mucin (MUC5AC) decreased independently of L. plantarum 299v. In conclusion, the data suggest that the effect of L. plantarum 299v on iron metabolism is mediated through driving the Fe3+/DCYTB axis.
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| 10. |
- Tarczykowska, Agata, 1989, et al.
(författare)
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Differential Effects of Iron Chelates vs. Iron Salts on Induction of Pro-Oncogenic Amphiregulin and Pro-Inflammatory COX-2 in Human Intestinal Adenocarcinoma Cell Lines
- 2023
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Ingår i: International Journal of Molecular Sciences. - : MDPI AG. - 1661-6596 .- 1422-0067. ; 24:6
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Tidskriftsartikel (refereegranskat)abstract
- We previously showed that two iron compounds that are orally ingested by humans, namely ferric EDTA and ferric citrate, can induce an oncogenic growth factor (amphiregulin) in human intestinal epithelial adenocarcinoma cell lines. Here, we further screened these iron compounds, plus four other iron chelates and six iron salts (i.e., 12 oral iron compounds in total), for their effects on biomarkers of cancer and inflammation. Ferric pyrophosphate and ferric EDTA were the main inducers of amphiregulin and its receptor monomer, IGFr1. Moreover, at the maximum iron concentrations investigated (500 µM), the highest levels of amphiregulin were induced by the six iron chelates, while four of these also increased IGfr1. In addition, we observed that ferric pyrophosphate promoted signaling via the JAK/STAT pathway by up-regulating the cytokine receptor subunit IFN-γr1 and IL-6. For pro-inflammatory cyclooxygenase-2 (COX-2), ferric pyrophosphate but not ferric EDTA elevated intracellular levels. This, however, did not drive the other biomarkers based on COX-2 inhibition studies and was probably downstream of IL-6. We conclude that of all oral iron compounds, iron chelates may particularly elevate intracellular amphiregulin. Ferric pyrophosphate additionally induced COX-2, probably because of the high IL-6 induction that was observed with this compound.
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