Stability and Biaxial Behavior of Fresh Cheese Coated with Nanoliposomes Encapsulating Grape Seed Tannins and Polysaccharides Using Immersion and Spray Methods.

In the food industry context, where fresh cheese stands out as a highly perishable product with a short shelf life, this study aimed to extend its preservation through multi-layer edible coatings. The overall objective was to analyze the biaxial behavior and texture of fresh cheese coated with nanoliposomes encapsulating grape seed tannins (NTs) and polysaccharides (hydroxypropyl methylcellulose; HPMC and kappa carrageenan; KC) using immersion and spray methods, establishing comparisons with uncoated cheeses and commercial samples, including an accelerated shelf-life study. NT, HPMC, and KC were employed as primary components in the multi-layer edible coatings, which were applied through immersion and spray. The results revealed significant improvements, such as a 20% reduction in weight loss and increased stability against oxidation, evidenced by a 30% lower peroxide index than the uncoated samples. These findings underscore the effectiveness of edible coatings in enhancing the quality and extending the shelf life of fresh cheese, highlighting the innovative application of nanoliposomes and polysaccharide blends and the relevance of applying this strategy in the food industry. In conclusion, this study provides a promising perspective for developing dairy products with improved properties, opening opportunities to meet market demands and enhance consumer acceptance.

Physicochemical Properties of Nanoliposomes Encapsulating Grape Seed Tannins Formed with Ultrasound Cycles.

Grape seeds are an excellent source of flavonoids and tannins with powerful antioxidant properties. However, the astringency of tannins limits their direct incorporation into food. To overcome this challenge, we investigated the encapsulation of grape seed tannins within nanoliposomes formed by ultrasound cycling. We characterized the nanoliposomes' physicochemical properties, including encapsulation efficiency, antioxidant activity, stability, microstructure, and rheological properties. Our findings reveal that the nanoliposomes exhibited excellent stability under refrigerated conditions for up to 90 days with a mean particle size of 228 ± 26 nm, a polydispersity index of 0.598 ± 0.087, and a zeta potential of -41.6 ± 1.30 mV, maintaining a spherical multilamellar microstructure. Moreover, they displayed high antioxidant activity, with encapsulation efficiencies of 79% for epicatechin and 90% for catechin. This innovative approach demonstrates the potential of using ultrasound-assisted nanoliposome encapsulation to directly incorporate grape seed tannins into food matrices, providing a sustainable and efficient method for enhancing their bioavailability and functionality.

Efecto del virus del síndrome reproductivo y respiratorio porcino (PRRS) en células dendríticas de cerdo derivadas de monocitos / Effect of porcine reproductive and respiratory syndrome (PRRS) virus on porcine monocyte-derived dendritic cells

Dendritic cells (DC) are considered the most important antigen presenting cells of the immune system. Its anatomical location (skin, mucosa and peripheral blood), the expression of receptors to recognize pathogens, the expression of co-stimulatory molecules (CD80/86), the major histocompatibility complex (MHC) class I and II, and the production of cytokines (such as IFN-α, IL-10, IL-12) confers to these cells the characteristic to regulate innate and adaptive immune responses. The objective of this work was to evaluate the effects of the porcine reproductive and respiratory virus (PRRS) in mature DC. DC were generated from blood monocytes using IL-4 and GM-CSF and were stimulated with lipopolysaccharide (LPS) to induce their maturation. The results show that the expression of CD14 and CD172a molecules in infected DC was not affected, while MHC II and CD80/86 expression was diminished. This decrease seems to affect the allogenic proliferation of lymphocytes stimulated with infected DC. On the other hand, the virus increases mRNA expression of IL-10 and TNF-α, and diminishes that for IL-1 β and IL-6. The results obtained could explain, in part, the immunophatology of the disease.

Las células dendríticas (DC) son las presentadoras de antígeno más importantes del sistema inmune. Su localización anatómica (piel, mucosas y sangre periférica), la expresión de receptores para reconocer patógenos, la expresión de moléculas de coestimulación (CD80/86), del complejo principal de histocompatibilidad (MHC) clases I y II, y la producción de citocinas (IFN-α, IL-10, IL-12), les confiere una característica única para regular las respuestas inmune innata y adaptativa. El objetivo de este trabajo fue evaluar el efecto del virus de síndrome reproductivo y respiratorio porcino (PRRS) en DC maduras. Se generaron células dendríticas a partir de monocitos utilizando IL-4 y GM-CSF y se estimularon con lipopolisacárido (LPS) para inducir su maduración. Los resultados muestran que la expresión de las moléculas CD14 y CD172a no se altera en las DC infectadas, mientras que la expresión de MHC II y CD80/86 se ve disminuida. Esta disminución parece afectar la proliferación alogénica de linfocitos estimulados con DC infectadas. Asimismo, el virus aumenta la expresión del ARNm de IL-10 y TNF-α, y disminuye la de IL-1 β e IL-6. Lo anterior explica, en parte, la inmunopatología de la enfermedad.