Effect of kaolin impregnated with calico plant extract on properties of starch films.

Starch film has poor tensile properties and poor water resistance. We aimed to improve these properties by adding kaolin impregnated with calico plant extract (CP-Kaolin). UV-Vis spectrophotometry showed that the calico plant extract (CPE) contained 4867.52 mg/L of total phenolic compounds and betacyanins were the predominant constituents. CP-Kaolin was characterized by Fourier transform infrared spectroscopy (FTIR), zeta potential, scanning electron microscopy (SEM) and x-ray diffraction (XRD) analysis. FTIR analysis showed that betacyanins were adsorbed on kaolin via hydrogen bonding. Zeta potential analysis confirmed the adsorption of betacyanins on kaolin. The intercalation of betacyanins between kaolin platelets was observed by XRD. SEM revealed that CP-Kaolin was well dispersed and embedded within the starch matrix. It was found that the addition of 10 wt% of CP-Kaolin increased the water resistance, tensile strength and thermal stability of starch film. Moreover, starch film containing 10 wt% of CP-Kaolin was sensitive to the change in pH of the fish during storage. Therefore, the addition of CP-Kaolin improved the properties of starch film and starch film composite with CP-Kaolin could be applied as a smart packaging in the food industry.

Oral Administration of a Phage Cocktail to Reduce Salmonella Colonization in Broiler Gastrointestinal Tract-A Pilot Study.

Salmonella contamination in poultry meat products can lead to serious foodborne illness and economic loss from product recalls. It is crucial to control Salmonella contamination in poultry from farm to fork. Bacteriophages (phages) are viruses of bacteria that offer several advantages, especially their specificity to target bacteria. In our study, three Salmonella phages (vB_SenS_KP001, vB_SenS_KP005, and vB_SenS_WP110) recovered from a broiler farm and wastewater treatment stations showed high lysis ability ranging from 85.7 to 96.4% on over 56 serovars of Salmonella derived from several sources, including livestock and a broiler farm environment. A three-phage cocktail reduced S. Enteritidis and S. Typhimurium, in vitro by 3.9 ± 0.0 and 3.9 ± 0.2 log units at a multiplicity of infection (MOI) of 103 and 3.8 ± 0.4 and 4.1 ± 0.2 log units at MOI of 104 after 6 h post-phage treatment. A developed phage cocktail did not cause phage resistance in Salmonella during phage treatments for three passages. Phages could survive under simulated chicken gastrointestinal conditions in the presence of gastric acid for 2 h (100.0 ± 0.0% survivability), bile salt for 1 h (98.1 ± 1.0% survivability), and intestinal fluid for 4 h (100 ± 0.0% survivability). Each phage was in the phage cocktail at a concentration of up to 9.0 log PFU/mL. These did not cause any cytotoxicity to human fibroblast cells or Caco-2 cells as indicated by the percent of cell viability, which remained nearly 100% as compared with the control during 72 h of co-culture. The phage cocktail was given to broilers raised in commercial conditions at a 9 log PFU/dose for five doses, while naturally occurring Salmonella cells colonized in the gastrointestinal tract of broilers were significantly reduced as suggested by a considerably lower Salmonella prevalence from over 70 to 0% prevalence after four days of phage treatment. Our findings suggest that a phage cocktail is an effective biocontrol agent to reduce Salmonella present in the guts of broilers, which can be applied to improve food safety in broiler production.

MicroRNA Isolation by Trizol-Based Method and Its Stability in Stored Serum and cDNA Derivatives.

MicroRNAs (miRNAs) are small, non-coding RNA molecules that regulate gene expression at the post-transcriptional level. Since aberrant expression of miRNAs has been proposed as usage for blood-based biomarkers, hence reliable techniques for miRNA isolation as well as stability of miRNAs in various stored conditions needs to be explored. This present study aimed to investigate the efficacy of the Trizol-based isolation technique and the stability of miRNAs in stored serum and cDNA derivatives. Total RNA, including miRNAs, was isolated from human serum and a comparison of the efficiency of the Trizol®LS reagent isolation method against the miRNeasy®mini kit was conducted. Expression of RNU6, miR-145, and miR-20a was determined by quantitative real-time polymerase chain reaction (qRT-PCR). We showed that Trizol®LS isolation yielded significantly lower RNA concentrations than that of the miRNeasy®mini kit by approximately 35%. Purity of the isolated RNAs by both methods was similar. RNU6, miR-145, and miR-20a degraded at room temperature, but all genes were stable at 4ºC, -20ºC and -80ºC for a 72-hrs period, in both serum and cDNA storage conditions. In the stored cDNA derivatives, we observed the stability of RNU6, miR-145, and miR-20a for 3 months at -20ºC, and all genes also resisted 4 repeated freeze-thaw cycles at -20ºC. In conclusion, the Trizol-based method is efficient as well as economical to use for quantification of circulating miRNAs. In addition, we proposed that the storage of miRNA-derived cDNAs may be an alternative choice to avoid the stability effect.

Knockdown of 14-3-3γ Suppresses Epithelial-Mesenchymal Transition and Reduces Metastatic Potential of Human Non-small Cell Lung Cancer Cells.

BACKGROUND/AIM: 14-3-3γ is involved in the metastasis of lung cancer cells. However, its functional roles in tumor cell invasion and the underlying mechanisms are still not understood. In this study, the roles and molecular mechanisms of 14-3-3γ in epithelial-mesenchymal transition (EMT), migration, and invasion were investigated using A549 and H358 non-small cell lung cancer (NSCLC) cell lines. MATERIALS AND METHODS: siRNA against 14-3-3γ was used to suppress 14-3-3γ expression. Expression levels of proteins were detected by western blotting. Activity of matrix metalloproteinases (MMP)-2 and MMP9 was determined by gelatin zymography. Cell migration and invasion were analyzed using the Transwell assay. RESULTS: Knockdown of 14-3-3γ resulted in a significant reduction of expression of EMT-associated proteins in NSCLC cell lines, and led to significant reduction in invasion and migration by approximately 59% and 39% in A549 cells, and 65% and 62% in H358 cells, respectively. In addition, MMP2 and MMP9 activity was significantly reduced in both NSCLC cell lines after down-regulation of 14-3-3γ. CONCLUSION: Our results suggest that knockdown of 14-3-3γ may be a potential strategy for suppressing metastasis of lung cancer by inhibiting MMP2 and MMP9 through regulation of EMT.