Establishment and Characterization of Stable Zein/Glycosylated Lactoferrin Nanoparticles to Enhance the Storage Stability and in vitro Bioaccessibility of 7,8-Dihydroxyflavone

In this work, the lactoferrin (LF) was glycosylated by dextran (molecular weight 10, 40, and 70 kDa, LF 10K, LF 40K, and LF 70K) via Maillard reaction as a stabilizer to establish zein/glycosylated LF nanoparticles and encapsulate 7,8-dihydroxyflavone (7,8-DHF). Three zein/glycosylated LF nanoparticles (79.27–87.24 nm) with low turbidity (<0.220) and polydispersity index (PDI) (<0.230) were successfully established by hydrophobic interactions and hydrogen bonding. Compared with zein/LF nanoparticles, zein/glycosylated LF nanoparticles further increased stability to ionic strength (0–500 mM NaCl) at low pH conditions. Zein/glycosylated LF nanoparticles had nanoscale spherical shape and glycosylated LF changed surface morphology of zein nanoparticles. Besides, encapsulated 7,8-DHF exhibited an amorphous state inside zein/glycosylated LF nanoparticles. Most importantly, zein/glycosylated LF nanoparticles had good water redispersibility, high encapsulation efficiency (above 98.50%), favorable storage stability, and bioaccessibility for 7,8-DHF, particularly LF 40K. Collectively, the above research provides a theoretical reference for the application of zein-based delivery systems.

Compuestos antioxidantes y su bioaccesibilidad in vitro de la zanahoria (Daucus carota): cambios por procesos térmicos

La zanahoria (Daucus carota) pertenece a la familia de las Umbelíferas, es un vegetal rico en β-carotenos y otros antioxidantes. El objetivo de la revisión fue analizar el efecto del procesamiento térmico de la zanahoria sobre los compuestos antioxidantes y su bioaccesibilidad. Los tratamientos térmicos varían de acuerdo a las condiciones de temperatura y tiempo a los que son sometidos los alimentos. Investigaciones han reportado la aplicación de tratamientos térmicos en zanahoria como hervido, pasteurización, ultrapasteurización, esterilización comercial, escaldado, cocción a presión y freído. Existen cambios significativos en los parámetros de color cuando las zanahorias son escaldadas, los valores de a* y b* disminuyeron respecto a las muestras no tratadas. El contenido de compuestos fenólicos y su bioaccesibilidad se reduce con el escaldado y la pasteurización. La zanahoria Egmont Gold tratada a 80°C incrementó la concentración de ácido ascórbico (318.82±18.40 µg/g ps (peso seco)) en 23.84%, respecto a la muestra a temperatura ambiente (258.12±32.56 µg/g ps), debido a la inactivación de la enzima ácido ascórbico oxidasa. La cocción a presión (5134.5±75.3 µg/100 g pf (peso fresco)), hervido (6740.3±58.6 µg/100 g pf), freído (5926.4±106.6 µg/100 g pf), escaldado (87.70±2.75 µg/g pf) y secado (882-1079 mg/kg masa seca) de la zanahoria, provocó una disminución de carotenoides (2.53-31.58%). Por el contrario, cuando se analizó la bioaccesibilidad in vitro, la cocción a presión, hervido y freído incrementaron la bioaccesibilidad de los carotenoides (29.80%, 25.45% y 38.47%, respectivamente) en comparación con la zanahoria sin tratami The carrot (Daucus carota) belongs to the Umbelliferae family, is vegetable rich in β-carotenes and other antioxidants. The aim of the review was to analyze the effect of thermal processing of carrot on antioxidant compounds and their bioaccessibility. The thermal treatments vary according to the temperature and time conditions to which the food is subjected. Researchers have reported the application of thermal treatments to carrots such as boiling, pasteurization, ultra-pasteurization, commercial sterilization, blanching, pressure cooking and frying. There are significant changes in the colour parameters when the carrots are blanched, the values ​​of a* and b* decreased with respect to the untreated samples. The content of phenolic compounds and their bioaccessibility decreased with the blanching and pasteurization. Egmont Gold carrot treated at 80°C increased the concentration of ascorbic acid (318.82 ± 18.40 µg/g dw (dry weight)) by 23.84%, with respect to the sample at room temperature (258.12 ± 32.56 µg/g dw), due to the inactivation of the enzyme ascorbic acid oxidase. Pressure cooking (5134.5 ± 75.3 µg/100 g fw (fresh weight)), boiled (6740.3 ± 58.6 µg/100 g fw), frying (5926.4 ± 106.6 µg/100 g fw), blanched (87.70 ± 2.75 µg/g fw) and drying (882-1079 mg/kg dry mass) of the carrot, caused a decrease in carotenoids (2.53-31.58%). On the contrary, when was analyzed the in vitro bioaccessibility, pressure cooking, boiling and frying increased the bioaccessibility of carotenoids (29.80%, 25.45% and 38.47%, respectively) compared to carrots without treatment (16.80%), this behaviour also occurs in pasteurized, sterilized, ultra-pasteurized and dehydrated carrot pulp. However, the bioaccessibility of carrot antioxidant compounds depends on the polysaccharides of the cell membrane, proteins and other factors of the food matrix. ento (16.80%), este comportamiento también ocurre en la pulpa de zanahoria pasteurizada, esterilizada, ultrapasteurizada y deshidratada. Sin embargo, la bioaccesibilidad de los compuestos antioxidantes de la zanahoria depende de los polisacáridos de la membrana celular, proteínas y otros factores de la matriz alimentaria.

Influence of Phenolic-Food Matrix Interactions on In Vitro Bioaccessibility of Selected Phenolic Compounds and Nutrients Digestibility in Fortified White Bean Paste

This model study aimed to evaluate the effect of phenolic–food matrix interactions on the in vitro bioaccessibility and antioxidant activity of selected phenolic compounds (gallic acid, ferulic acid, chlorogenic acid, quercetin, apigenin, and catechin) as well as protein and starch digestibility in fortified white bean paste. The magnitude of food matrix effects on phenolics bioaccessibility and antioxidant activity was estimated based on “predicted values” and “combination indexes”. Furthermore, the protein–phenolics interactions were investigated using electrophoretic and chromatographic techniques. The results demonstrated phenolic–food matrix interactions, in most cases, negatively affected the in vitro bioaccessibility and antioxidant activity of phenolic compounds as well as nutrient digestibility. The lowest in vitro bioaccessibility of phenolic compounds in fortified paste was found for quercetin (45.4%). The most negative impact on the total starch digestibility and relative digestibility of proteins was observed for catechin–digestibility lower by 14.8%, and 21.3% (compared with control), respectively. The observed phenolic–food matrix interactions were strictly dependent on the applied phenolic compound, which indicates the complex nature of interactions and individual affinity of phenolic compounds to food matrix components. In conclusion, phenolic–food matrix interactions are an important factor affecting the nutraceutical and nutritional potential of fortified products.