Improved Sensitivity of Allergen Detection by Immunoaffinity LC-MS/MS Using Ovalbumin as a Case Study

Vitamin D deficiency due to, e.g., nutritional and life style reasons is a health concern that is gaining increasing attention over the last two decades. Vitamin D3, the most common isoform of vitamin D, is only available in food derived from animal sources. However, mushrooms and yeast are rich in ergosterol. This compound can be converted into vitamin D2 by UV-light, and therefore act as a precursor for vitamin D. Vitamin D2 from UV-irradiated mushrooms has become an alternative source of vitamin D, especially for persons pursuing a vegan diet. UV-irradiated baker’s yeast (Saccharomyces cerevisiae) for the production of fortified yeast-leavened bread and baked goods was approved as a Novel Food Ingredient in the European Union, according to Regulation (EC) No. 258/97. The Scientific Opinion provided by the European Food Safety Authority Panel on Dietetic Products, Nutrition, and Allergies has assessed this Novel Food Ingredient as safe under the intended nutritional use. However, recent findings on the formation of side products during UV-irradiation, e.g., the photoproducts tachysterol and lumisterol which are compounds with no adequate risk assessment performed, have only been marginally considered for this EFSA opinion. Furthermore, proceedings in analytics can provide additional insights, which might open up new perspectives, also regarding the bioavailability and potential health benefits of vitamin D-fortified mushrooms and yeast. Therefore, this review is intended to give an overview on the current status of UV irradiation in mushrooms and yeast in general and provide a detailed assessment on the potential health effects of UV-irradiated baker’s yeast

Immunogenic potential of a Salmonella Typhimurium live vaccine for pigs against monophasic Salmonella Typhimurium DT 193

Abstract Background Monophasic Salmonella Typhimurium (mSTM) strains account for up to 8.6% of all human Salmonellosis cases. They have an increasing prevalence during recent years and several human cases with hospitalisation were reported. These strains are often isolated from pigs and pork - one primary source of human infection. A Salmonella Typhimurium (STM) live vaccine has been proven successful in controlling of STM infections in pigs for many years. The aim of this study was to test the immunogenicity of the vaccine in weaners during oral challenge with a virulent mSTM strain and to examine the kinetics of STM-specific IgA, IgM and IgG antibodies induced by vaccination and infection. Results Despite clinical signs being present in both groups, the vaccination led to a significant reduction of diarrhoea, overall clinical symptoms and a milder elevation of the body temperature. Necropsy revealed fewer pathological lesions in the gastrointestinal tract of vaccinated compared to control animals. Moreover, in the ileal and caecal mucosa and in the ileocaecal lymph nodes the challenge strain burden was significantly reduced by vaccination. Significant differences in the antibody responses of both groups were present during the vaccination period and after infection. In vaccinated animals Salmonella-specific IgA and IgG antibody levels increased significantly after vaccination and were even more pronounced in response to challenge. In contrast, similarly low levels of IgM antibodies were detected during the vaccination period in both vaccinated and non-vaccinated animals. However, after challenge IgM antibody levels increased significantly in control pigs while neither IgA nor IgG antibodies were detectable. Conclusion The data demonstrate that mSTM can evoke clinical signs in weaners. Due to the vaccination their incidence and magnitude were significantly milder. Vaccination also led to a significantly reduced challenge strain burden in the intestine and the lymph nodes which is comparable to previous studies using the same vaccine in a challenge with biphasic STM. Therefore, it is concluded that this vaccine induces immunity against monophasic and biphasic STM strains. Furthermore, the results of antibody profiles in response to vaccination and infection provide additional evidence for humoral immune mechanisms triggered during Salmonella infection or vaccination

Fermentation of Lupin Protein Hydrolysates—Effects on Their Functional Properties, Sensory Profile and the Allergenic Potential of the Major Lupin Allergen Lup an 1

Lupin protein isolate was treated using the combination of enzymatic hydrolysis (Papain, Alcalase 2.4 L and Pepsin) and lactic acid fermentation (Lactobacillus sakei ssp. carnosus, Lactobacillus amylolyticus and Lactobacillus helveticus) to investigate the effect on functional properties, sensory profile and protein integrity. The results showed increased foaming activity (2466–3481%) and solubility at pH 4.0 (19.7–36.7%) of all fermented hydrolysates compared to the untreated lupin protein isolate with 1613% of foaming activity and a solubility of 7.3 (pH 4.0). Results of the SDS-PAGE and Bead-Assay showed that the combination of enzymatic hydrolysis and fermentation of LPI was effective in reducing L. angustifolius major allergen Lup an 1 to a residual level of <0.5%. The combination of enzymatic hydrolysis and fermentation enables the production of food ingredients with good functional properties in terms of protein solubility and foam formation, with a balanced aroma and taste profile

Fermentation of Lupin Protein Hydrolysates—Effects on Their Functional Properties, Sensory Profile and the Allergenic Potential of the Major Lupin Allergen Lup an 1

Lupin protein isolate was treated using the combination of enzymatic hydrolysis (Papain, Alcalase 2.4 L and Pepsin) and lactic acid fermentation (Lactobacillus sakei ssp. carnosus, Lactobacillus amylolyticus and Lactobacillus helveticus) to investigate the effect on functional properties, sensory profile and protein integrity. The results showed increased foaming activity (2466–3481%) and solubility at pH 4.0 (19.7–36.7%) of all fermented hydrolysates compared to the untreated lupin protein isolate with 1613% of foaming activity and a solubility of 7.3 (pH 4.0). Results of the SDS-PAGE and Bead-Assay showed that the combination of enzymatic hydrolysis and fermentation of LPI was effective in reducing L. angustifolius major allergen Lup an 1 to a residual level of <0.5%. The combination of enzymatic hydrolysis and fermentation enables the production of food ingredients with good functional properties in terms of protein solubility and foam formation, with a balanced aroma and taste profile

Improved Sensitivity of Allergen Detection by Immunoaffinity LC-MS/MS Using Ovalbumin as a Case Study

Vitamin D deficiency due to, e.g., nutritional and life style reasons is a health concern that is gaining increasing attention over the last two decades. Vitamin D3, the most common isoform of vitamin D, is only available in food derived from animal sources. However, mushrooms and yeast are rich in ergosterol. This compound can be converted into vitamin D2 by UV-light, and therefore act as a precursor for vitamin D. Vitamin D2 from UV-irradiated mushrooms has become an alternative source of vitamin D, especially for persons pursuing a vegan diet. UV-irradiated baker’s yeast (Saccharomyces cerevisiae) for the production of fortified yeast-leavened bread and baked goods was approved as a Novel Food Ingredient in the European Union, according to Regulation (EC) No. 258/97. The Scientific Opinion provided by the European Food Safety Authority Panel on Dietetic Products, Nutrition, and Allergies has assessed this Novel Food Ingredient as safe under the intended nutritional use. However, recent findings on the formation of side products during UV-irradiation, e.g., the photoproducts tachysterol and lumisterol which are compounds with no adequate risk assessment performed, have only been marginally considered for this EFSA opinion. Furthermore, proceedings in analytics can provide additional insights, which might open up new perspectives, also regarding the bioavailability and potential health benefits of vitamin D-fortified mushrooms and yeast. Therefore, this review is intended to give an overview on the current status of UV irradiation in mushrooms and yeast in general and provide a detailed assessment on the potential health effects of UV-irradiated baker’s yeast

Improved Sensitivity of Allergen Detection by Immunoaffinity LC-MS/MS Using Ovalbumin as a Case Study

Vitamin D deficiency due to, e.g., nutritional and life style reasons is a health concern that is gaining increasing attention over the last two decades. Vitamin D3, the most common isoform of vitamin D, is only available in food derived from animal sources. However, mushrooms and yeast are rich in ergosterol. This compound can be converted into vitamin D2 by UV-light, and therefore act as a precursor for vitamin D. Vitamin D2 from UV-irradiated mushrooms has become an alternative source of vitamin D, especially for persons pursuing a vegan diet. UV-irradiated baker’s yeast (Saccharomyces cerevisiae) for the production of fortified yeast-leavened bread and baked goods was approved as a Novel Food Ingredient in the European Union, according to Regulation (EC) No. 258/97. The Scientific Opinion provided by the European Food Safety Authority Panel on Dietetic Products, Nutrition, and Allergies has assessed this Novel Food Ingredient as safe under the intended nutritional use. However, recent findings on the formation of side products during UV-irradiation, e.g., the photoproducts tachysterol and lumisterol which are compounds with no adequate risk assessment performed, have only been marginally considered for this EFSA opinion. Furthermore, proceedings in analytics can provide additional insights, which might open up new perspectives, also regarding the bioavailability and potential health benefits of vitamin D-fortified mushrooms and yeast. Therefore, this review is intended to give an overview on the current status of UV irradiation in mushrooms and yeast in general and provide a detailed assessment on the potential health effects of UV-irradiated baker’s yeast

Improved Sensitivity of Allergen Detection by Immunoaffinity LC-MS/MS Using Ovalbumin as a Case Study

Food allergies are caused by severe hypersensitivity to specific food allergens such as the egg protein ovalbumin. It is therefore important to test food products for the presence of allergens to protect allergic people from accidental ingestion. For egg detection, ELISA is the only reasonable commercially available test format, although the recognition of target allergens can be affected by food processing, which may lead to false negative results. Current mass spectrometry-based detection methods may overcome this issue, but these approaches are often less sensitive. Here we combined the advantages of antibody-based and MS-based methods by developing an immunoaffinity LC-MS/MS technique to detect the common egg allergen Gal d 2. We investigated the principal functionality of this method with incurred cookie material containing whole egg powder. We found that the new method matched easily the sensitivity of egg specific ELISA tests. Further western blot experiments indicated that this strategy may be unaffected by food processing, providing an important alternative strategy for the detection and quantification of allergens in food