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Dietary antioxidants are an important preservative in food and have been suggested to help in disease prevention. With consumer demands for less synthetic and safer additives in food products, the food industry is searching for antioxidants that can be marketed as natural. Peptides derived from natural proteins show promise, as they are generally regarded as safe and potentially contain other beneficial bioactivities. Antioxidative peptides are usually obtained by testing various peptides derived from hydrolysis of proteins by a selection of proteases. This slow and cumbersome trial-and-error approach to identify antioxidative peptides has increased interest in developing computational approaches for prediction of antioxidant activity and thereby reduce laboratory work. A few antioxidant predictors exist, however, no tool predicting the antioxidative properties of peptides is, to the best of our knowledge, currently available as a web-server. We here present the AnOxPePred tool and web-server (http://services.bioinformatics.dtu.dk/service.php?AnOxPePred-1.0) that uses deep learning to predict the antioxidant properties of peptides. Our model was trained on a curated dataset consisting of experimentally-tested antioxidant and non-antioxidant peptides. For a variety of metrics our method displays a prediction performance better than a k-NN sequence identity-based approach. Furthermore, the developed tool will be a good benchmark for future predictors of antioxidant peptides.

Nowadays, there is a growing interest in the physiological benefits of natural antioxidants in foods. Honey bee products, especially propolis and pollen, have strong antioxidative activity and beneficial effects in human body. The aim of this study was to determine the total phenolic and total flavonoid contents and antioxidant activities of propolis and pollen, as well as bioaccessibility of these products by an in-vitro model simulating gastrointestinal digestion. Total phenolic content, total flavonoid content and antioxidant activity analysis were applied to all samples as well as samples collected after the application of in-vitro gastrointestinal method. Phenolic profiles of propolis and pollen samples were also identified by HPLC-PDA. Results indicated that total phenolic contents of IN fractions (bioaccessible fraction) of propolis and pollen was 2.0 and 2.1 mg GAE/g; total flavonoid content was 0.9 and 0.2 mg QE/g; total antioxidant activity was 19.6 and 0.6 mg TE/g, respectively. Percentages of the IN fraction of propolis and pollen were 1% and 9% for total phenolic content; 0.2% and 1% for total flavonoid content; 4% and 3% for total antioxidant activity. Phenolic compounds including caffeic acid, p-coumaric acid, ferrulic acid, quercetin, pinobanksin, apigenin, t-cinnamic acid, luteolin, pinocembrin, chrysin, galangin, kaempferol and pinostrobin were detected in propolis, and 2-hydroxycinnamic acid, quercetin-3glucoside, quercetin, myricetin, luteolin, quercetin-3-galactoside, kaempferol, and galangin were detected in pollen samples. Investigación de la bio-accesibilidad in vitro de propóleos y el polen que utilizan un sistema de digestión gastrointestinal simulada ResumenHoy en día, hay un creciente interés en los beneficios fisiológicos de los antioxidantes naturales presentes en los alimentos. Productos de la abeja de la miel, especialmente propóleo y polen, tienen una fuerte actividad antioxidante y efectos beneficiosos para el cuerpo humano. El objetivo de este estudio fue determinar el contenido total fenólico y de flavonoides y la actividad antioxidante de propóleos y polen así como la bio-accesibilidad de estos productos mediante un modelo in vitro que simula la digestión gastrointestinal. Se analizaron el contenido fenólico total, el contenido total de flavonoides y la actividad antioxidante en todas las muestras, así como en las muestras recogidas después de la aplicación del método in vitro gastrointestinal. Los perfiles fenólicos del propóleo y las muestras de polen también fueron identificados por HPLC-PDA. Los resultados indicaron que el contenido total de fenólicos de fracciones (fracción EN bioaccesibles) de propóleos y polen fue de 2,0 y 2,1 mg GAE/g; el contenido total de flavonoides fue de 0,9 y 0,2 mg QE/g, la actividad antioxidante total fue de 19,6 y 0,6 mg TE/g, respectivamente. Los porcentajes de la fracción IN del propóleo y el polen fueron 1% y el 9% para el contenido de fenoles totales, 0,2% y 1% para el contenido total de flavonoides; 4% y 3% para la actividad antioxidante ...

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Modified phosphatidylcholine with different alkyl chain length and covalently attached caffeic acid affects the physical and oxidative stability of omega-3 delivery 70% oil-in-water emulsions. Food Chemistry, 289,[490][491][492][493][494][495][496][497][498][499]