Fabrication of multifunctional ethyl cellulose/gelatin-based composite nanofilm for the pork preservation and freshness monitoring.

In this study, an active and intelligent nanofilm for monitoring and maintaining the freshness of pork was developed using ethyl cellulose/gelatin matrix through electrospinning, with the addition of natural purple sweet potato anthocyanin. The nanofilm exhibited discernible color variations in response to pH changes, and it demonstrated a higher sensitivity towards volatile ammonia compared with casting film. Notably, the experimental findings regarding the wettability and pH response performance indicated that the water contact angle between 70° and 85° was more favorable for the smart response of pH sensitivity. Furthermore, the film exhibited desirable antioxidant activities, water vapor barrier properties and also good antimicrobial activities with the incorporation of ε-polylysine, suggesting the potential as a food packaging film. Furthermore, the application preservation outcomes revealed that the pork packed with the nanofilm can prolong shelf life to 6 days, more importantly, a distinct color change aligned closely with the points indicating the deterioration of the pork was observed, changing from light pink (indicating freshness) to light brown (indicating secondary freshness) and then to brownish green (indicating spoilage). Hence, the application of this multifunctional film in intelligent packaging holds great potential for both real-time indication and efficient preservation of the freshness of animal-derived food items.

Effect of glutamine on the systemic innate immune response in broiler chickens challenged with Salmonella pullorum.

BACKGROUND: The objective of this study was to evaluate the effects of glutamine on the growth performance and systemic innate immune response in broiler chickens challenged with Salmonella pullorum. A total of 600 one-day-old Arbor Acres broiler chickens were assigned randomly to 6 dietary treatments with 10 replicates for a 21-day feeding experiment. The experimental treatments were as follows: the control treatment (birds fed the basal diet), the Gln1 treatment, and the Gln 2 treatment (birds fed the basal diet supplemented with 0.5%, and 1.0% Glutamine, respectively). At 3 d of age, half of the birds from each treatment were challenged oral gavage with 2.0 × 104 CFU/mL of S. pullorum suspension (1.0 mL per bird) or an equivalent amount of sterile saline alone, which served as a control. RESULTS: The results showed that S. pullorum infection had adverse effects on the average daily feed intake, average daily gain, and feed conversion ratio of broiler chickens compared with those of the CON treatment on d 7, decreased the spleen and bursa of fabricius relative weights (except on d 21), serum immunoglobulin A (IgA),immunoglobulin G (IgG), and immunoglobulin M (IgM) concentrations, and spleen melanoma differentiation-associated gene 5 (MDA5) and laboratory of genetics and physiology gene 2 (LGP2) mRNA expression levels, and increased the mRNA expression levels of spleen Nodinitib-1 (NOD1), Toll-like receptors 2,4 (TLR2, TLR4), DNA-dependent activator of IFN-regulatory factors (DAI), mitochondrial antiviral-signaling protein (MAVS), P50, P65, and RelB on d 4, 7, 14, and 21. Supplementation with Gln improved the relative weights of the spleen and bursa of Fabricius (except on d 21), increased the serum IgA, IgG, and IgM concentrations and the mRNA expression levels of spleen MDA5 and LGP2, and decreased the mRNA expression levels of spleen NOD1, TLR2, TLR4, DAI, MAVS, P50, P65, and RelB of S. pullorum-challenged broiler chickens. CONCLUSION: These results indicate that Gln might stimulate the systemic innate immune responses of the spleen in broiler chickens challenged with S. pullorum.

Effect of glutamine on the growth performance, digestive enzyme activity, absorption function, and mRNA expression of intestinal transporters in heat-stressed chickens.

To explore the effect of glutamine (Gln) on the growth performance, digestive enzyme activity, absorption function and mRNA expression of intestinal transporters in heat-stressed chickens, 540 21-day-old Arbor Acres broilers were randomly assigned to a control group (no stress, NS), Gln group (Chickens were administered 0.5% and 1.0% Gln, respectively), heat stress group (HT), and Gln + HT group (Chickens were administered 0.5% and 1.0% Gln, respectively). The chickens in the HT and Gln + HT groups were reared under HT (36 ± 1 °C for 10 h/d and 22 ± 1 °C for 14 h/d), for 21 days. In contrast to the NS group, heat stress caused a reduction in the body weight gain (BWG); feed intake (FI); activity of trypsin, lipase, alkaline phosphatases, Ca2+ and Mg2+ adenosine triphosphatases, and Na+-K+-ATPase; and content of glutathione and d-xylose (P < 0.05) in the other groups. In addition, compared to the F:G and expression levels in the NS group, the heat stress increased the feed intake:body weight gain (F:G) and mRNA expression levels of SGLT1, CaBP-D28k, and L-GSBP (P < 0.05). Furthermore, HT-challenged birds were pretreated with Gln, the BWG; FI; activity of trypsin, lipase, alkaline phosphatase, Ca2+ and Mg2+ adenosine triphosphatases, and Na+-K+-ATPase; and content of glutathione and d-xylose (P < 0.05) were dramatically increased, but it decreased the F:G and mRNA expression levels of SGLT1, CaBP-D28k, and L-GSBP (P < 0.05) in the HT group. In summary, Gln can effectively improve growth performance and may promote digestion and absorption in the gastrointestinal tract by mediating the mRNA expression level of nutrient transporters and Gln metabolism in heat-stressed broilers.

Exploring optimal supplement strategy of medicinal herbs and tea extracts for bioelectricity generation in microbial fuel cells.

This first-attempt study used extracts of appropriate antioxidant abundant Camellia and non-Camellia tea and medicinal herbs as model ESs to stably intensify bioelectricity generation performance in microbial fuel cells (MFCs). As electron shuttles (ESs) could stimulate electron transport phenomena by significant reduction of electron transfer resistance, the efficiency of power generation for energy extraction in microbial fuel cells (MFCs) could be appreciably augmented. Using environmentally friendly natural bioresource as green bioresource of ESs is the most promising to sustainable practicability. As comparison of power-density profiles indicated, supplement of Camellia tea extracts would be the most appropriate, then followed non-Camellia Chrysanthemum tea and medicinal herbs. Antioxidant activities, total phenolic contents and power stimulating activities were all electrochemically associated. In particular, the extract of unfermented Camellia tea (i.e., green tea) was the most promising ESs to augment bioenergy extraction compared to other refreshing medicinal herb extracts.