Oncogenic and tumor suppressor pathways in subchronic aflatoxicosis in rats: Association with serum and urinary aflatoxin exposure biomarkers.

In this study, the changes in oncogenic and tumor suppressor signaling pathways in liver and their association with serum and urinary biomarkers of aflatoxin exposure were evaluated in Wistar rats fed diets containing aflatoxin B1 (AFB1) for 90 days. Rats were divided into four groups (n = 15 per group) and assigned to dietary treatments containing 0 (control), 50 (AFB50), 100 (AFB100) and 200 µg AFB1 kg-1 diet (AFB200). Multiple preneoplastic foci of hepatocytes marked with glutathione-S-transferase-placental form (GST-P) were identified in AFB100 and AFB200 groups. Hepatocellular damage induced by AFB1 resulted in overexpression of cyclin D1 and ß-catenin. The liver expression of retinoblastoma (Rb) and p27Kip1 decreased in AFB100 and AFB200 groups, confirming the favorable conditions for neoplastic progression to hepatocellular carcinoma. All samples from rats fed AFB1-contaminated diets had quantifiable AFB1-lysine in serum or urinary AFM1 and AFB1-N7-guanine, with mean levels of 20.42-50.34 ng mL-1, 5.31-37.68 and 39.15-126.37 ng mg-1 creatinine, respectively. Positive correlations were found between AFB1-lysine, AFM1 or AFB1-N7-guanine and GST-P+, ß-catenin+ and cyclin D1+ hepatocytes, while Rb + cells negatively correlated with those AFB1 exposure biomarkers. The pathways evaluated are critical molecular mechanisms of AFB1-induced hepatocarcinogenesis in rats.

Prolonging shelf life of chicken breast fillets by using plasma-improved chitosan/low density polyethylene bilayer film containing summer savory essential oil.

Cold plasma assay was potentially useful persuade surface modification. In this study, antimicrobial properties of chitosan and low density polyethylene bilayer film with method cold plasma incorporated with summer savory essential oil (SEO) (1, 2 and 3%) for extending shelf life of chicken breast fillets was investigated. Moreover, mechanical and physical properties of film were assessed. Result showed that plasma treatment could improvement properties film and increase shelf life processing. After plasma treatment chitosan/polyethylene film containing 3% summer savory essential oil decreased water vapor permeability and oxygen transmission rate chitosan film. Addition of summer savory essential oil to the two-layer film, also improved tensile strength and elongation at break of film. The bilayer film with 3% of essential oil treatment cold plasma was chosen for microbial analysis during storage. All samples plasma-treated, films for this study included polyethylene (PE), bilayer of polyethylene and chitosan (PE/Ch) and Chitosan containing essential oil in direct contact (D) and gas phase (G). Result showed that shelf life of fillets were extended in direct contact and gas phase treatments to 13 days at refrigerator. It was 6 days for polyethylene and 8 days for Chitosan treatments. Essential oil incorporated film also decreased thiobarbitoric acid value of sample during storage. Cold plasma has a high potential in active packaging and food preservation.

Reduction in Acrylamide Formation in Potato Crisps: Application of Extract and Hydrocolloid-Based Coatings.

ABSTRACT: Two different potato chip coatings-aqueous extracts including Zataria multiflora and Allium hirtifolium at concentrations of 1, 3, 5, and 7% and hydrocolloids individually or in combination-were used to decrease acrylamide content, and their effects on the characteristics of the product were then investigated. According to the results, the incorporation of hydrocolloids as the coating was more efficient in the reduction of acrylamide production than with the extracts. Also, the application of each extract and hydrocolloids individually can be considered a more efficient technique for acrylamide reduction than their mixture. In this regard, the economic aspects of the application of hydrocolloids in the coating of fried potato crisps can be evaluated.

Modifications of protein-based films using cold plasma.

In this research, the influence of different cold plasma treatments was investigated as a novel method for modification of protein film properties. The films were prepared from whey and gluten proteins using solvent casting method and then treated with vacuum low-pressure glow plasma using air and argon gases at 50 KW for 5, 10, and 15 min and further analyzed mechanically and physicochemically. The images of atomic force microscopy (AFM) revealed a significant increase in roughness of whey protein films after plasma treatment, while the roughness of treated gluten films diminished dramatically. Furthermore, the tensile strength of films improved significantly after 10 min of process, from 6.902 to 10.772 MPa and from 1.854 to 2.571 MPa for whey protein and gluten films, respectively. Introduction of functional groups such as CO and OC bonds plus cross link creation was observed by FTIR which could lead to changes in different film features. Although gas permeability of both edible polymers decreased significantly, other parameters including solubility and water vapor permeability of control and plasma treated (PT) films did not show dramatic differences. Therefore, the optimum condition and time of low-pressure glow plasma has the potential for modifying protein films.