Influence of amino acids on the formation of mutagenic/carcinogenic heterocydic amines in a model system

Mixtures of creatinine, glucose and various single amino acids were heated at 180°C for 10 min in an aqueous model system. The heated mixtures all showed mutagenic activity, ranging from 80 to 2400 TA98 revertant colonies/μmol creatinine with metabolic activation. Testing of HPLC fractions for mutagenic activity showed each mixture to contain several mutagenic components, some of which corresponded to known heterocyclic amines and others to unknown compounds. The presence of 2-amino-3-methyl-imidazo[4,5-f]quinoxaline, 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline and 2-amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline in most of the samples was established using HPLC with photodiode array detection and liquid chromatography/mass spectrometry with electrospray interface and single ion monitoring. In addition, 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, 3-amino-1,4-di-methyl-5H-pyrido[4,3-b]indole and 3-amino-1-methyl-5H-pyrido[4,3-b]indole and the co-mutagenic compounds 9H-pyrido[3,4-bindole and 1-methyl-9H-pyrido[3,4-b]indole were detected in some sample

Protective effect of mesoporous silica particles on encapsulated folates

Mesoporous silica particles (MSPs) are considered suitable supports to design gated materials for the encapsulation of bioactive molecules. Folates are essential micronutrients which are sensitive to external agents that provoke nutritional deficiencies. Folates encapsulation in MSPs to prevent degradation and to allow their controlled delivery is a promising strategy. Nevertheless, no information exists about the protective effect of MSPs encapsulation to prevent their degradation. In this work, 5-formyltetrahydrofolate (FO) and folic acid (FA) were entrapped in MSPs functionalized with polyamines, which acted as pH-dependent molecular gates. The stability of free and entrapped vitamins after acidic pH, high temperature and light exposure was studied. The results showed the degradation of FO after high temperature and acidic pH, whereas entrapped FO displayed enhanced stability. Free FA was degraded by light, but MSPs stabilized the vitamin. The obtained results point toward the potential use of MSPs as candidates to enhance stability and to improve the bioavailability of functional biomolecules.Authors gratefully acknowledge the financial support from the Ministerio de Economia y Competitividad (Projects AGL2012-39597-C02-01, AGL2012-39597-C02-02 and MAT2012-38429-C04-01), FEDER founding and the Generalitat Valenciana (Project PROMETEOII/2014/047). M.R.R. and E.P.E. are grateful to the Ministerio de Ciencia e Innovacion for their Grants (AP2010-4369 and AP2008-0620).Ruiz Rico, M.; Daubenschüz, H.; Pérez Esteve, E.; Marcos Martínez, MD.; Amorós, P.; Martínez Mañez, R.; Barat Baviera, JM. (2016). Protective effect of mesoporous silica particles on encapsulated folates. European Journal of Pharmaceutics and Biopharmaceutics. 105:9-17. https://doi.org/10.1016/j.ejpb.2016.05.016S91710

Beneficial Effects of Probiotic and Food Borne Yeasts on Human Health

Besides being important in the fermentation of foods and beverages, yeasts have shown numerous beneficial effects on human health. Among these, probiotic effects are the most well known health effects including prevention and treatment of intestinal diseases and immunomodulatory effects. Other beneficial functions of yeasts are improvement of bioavailability of minerals through the hydrolysis of phytate, folate biofortification and detoxification of mycotoxins due to surface binding to the yeast cell wall

Transitions at CpG Dinucleotides, Geographic Clustering of TP53 Mutations and Food Availability Patterns in Colorectal Cancer

Colorectal cancer is mainly attributed to diet, but the role exerted by foods remains unclear because involved factors are extremely complex. Geography substantially impacts on foods. Correlations between international variation in colorectal cancer-associated mutation patterns and food availabilities could highlight the influence of foods on colorectal mutagenesis. mutations from 12 countries/geographic areas. For food availabilities, we relied on data extracted from the Food Balance Sheets of the Food and Agriculture Organization of the United Nations. Dendrograms for mutation sites, mutation types and food patterns were constructed through Ward's hierarchical clustering algorithm and their stability was assessed evaluating silhouette values. Feature selection used entropy-based measures for similarity between clusterings, combined with principal component analysis by exhaustive and heuristic approaches. hotspots. Pearson's correlation scores, computed between the principal components of the datamatrices for mutation types, food availability and mutation sites, demonstrated statistically significant correlations between transitions at CpGs and both mutation sites and availabilities of meat, milk, sweeteners and animal fats, the energy-dense foods at the basis of “Western” diets. This is best explainable by differential exposure to nitrosative DNA damage due to foods that promote metabolic stress and chronic inflammation

Aktiv fondförvaltning på svenska marknaden : Svenska aktiefonders prestation i jämförelse mot passiv förvaltning i perioder av upp- och nedgång på Stockholmsbörsen mellan åren 1995-2010

I denna uppsats undersöks hur aktivt förvaltade svenska aktiefonder presterat i jämförelse mot passiv förvaltning i perioder av upp- och nedgång på Stockholmsbörsen mellan åren 1995-2010. I ett urval av 36 aktivt förvaltade Sverigefonder undersöks hur prestationerna står sig mot passiv förvaltning, om fondernas prestationer håller i sig över tid och om fondstorleken har betydelse för prestationen. Genom en uppdelning olik tidigare studier på fonders prestationer, där perioderna bestäms utefter marknadens upp- och nedgångscykler kan resultat tydligare framställas om aktivt förvaltade fonder presterar bättre än passiv förvaltning. Vi riskjusterar fondernas prestationer och jämför deras utveckling mot SIX Return Index och indexfonden Handelsbanken Mega Sverige Index (den passiva förvaltningen). Vi finner att aktiv förvaltning överlag inte lyckas genera högre avkastning än index i perioder av uppgångar men att de går bättre än index i nedgångar. Vidare finner vi inga tydliga samband på att prestationerna håller i sig över tid. Vi ser även svaga tendenser på att stora fonder (över fyra miljarder kronor i fondförmögenhet) presterar bättre än mindre fonder.