scholarly journals Development and Characterization of Bioactive Polypropylene Films for Food Packaging Applications

Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3478
Author(s):  
Adrian Krzysztof Antosik ◽  
Urszula Kowalska ◽  
Magdalena Stobińska ◽  
Paulina Dzięcioł ◽  
Magdalena Pieczykolan ◽  
...  
Keyword(s):  
Food Packaging ◽  
Antimicrobial Properties ◽  
The Novel ◽  
E Coli ◽  
Synthetic Product ◽  
Natural Agents ◽  
Plastic Materials ◽  
Study Results ◽  
Oregano Oil

Bioactive polypropylene (PP) films with active agents) presence for food packaging application have been prepared and characterized. The novel modified PP films were obtained via PP/additives systems regranulation and cast extrusion. The influence of two types of plasticizers (natural agents as well as commercial synthetic product) and bioactive additives on final features, e.g., mechanical properties, was evaluated. Moreover, the biocidal activity of the films was determined. Due to their functional properties, they are developed as additives to packaging plastic materials such as polyolefins. The study results presented in our work may indirectly contribute to environmental protection by reducing food waste. The aim of the work was to obtain innovative, functional packaging materials with an ability to prolong the shelf life of food products. The best antimicrobial properties were observed for the sample based on 5 wt.% oregano oil (OO) and 5 wt.% cedar oil (OC) in PP matrix. A microbial test revealed that the system causes total reduction in the following microorganisms: B. subtilis, E. coli, S. aureus, P. putida, C. albicans, A. alternata, F. oxysporum.

Determination of Bio Content in Polymers used in the Packaging of food Products

Radiocarbon ◽  
2019 ◽  
Vol 61 (6) ◽  
pp. 1973-1981
Author(s):  
C Telloli ◽  
A Rizzo ◽  
C Canducci ◽  
P Bartolomei
Keyword(s):  
Food Packaging ◽  
Liquid Scintillation ◽  
Scintillation Counting ◽  
Operational Parameters ◽  
Original Design ◽  
Plastic Materials ◽  
Different Types ◽  
Scintillation Method

ABSTRACTThe ENEA Radiocarbon Laboratory (Bologna, Italy) has been operating since 1985; it is the oldest among such laboratories operating in Italy and has been active for about 30 years in the field of dating of different types of samples with the radiocarbon (14C) liquid scintillation method. This study shows the detailed procedure for radiocarbon analysis on bioplastic materials by means of the synthesis of benzene, which includes CO2 production and purification, synthesis of acetylene, and synthesis and collection of benzene. The changes made to the original design of the synthesis procedures and the operational parameters adopted to optimize the combustion of the plastic materials are described. The measurement of 14C activity was performed using the liquid scintillation counting technique by a QuantulusTM 1220 low-background counter. The δ13C content was compared with the percentage of 14C concentration for the characterization of the bio content in plastic used in the food packaging.

scholarly journals Conditions to Prolonged Release of Microencapsulated Carvacrol on Alginate Films as Affected by Emulsifier Type and PH

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Silvia Matiacevich ◽  
Natalia Riquelme ◽  
María Lidia Herrera
Keyword(s):  
Storage Time ◽  
Antimicrobial Agents ◽  
Antimicrobial Properties ◽  
Edible Film ◽  
Initial Time ◽  
Tween 20 ◽  
Prolonged Release ◽  
E Coli ◽  
Fresh Foods

Alginate from algal biomass is used as edible film and the incorporation of antimicrobial agents improves its performance to increase the shelf-life of fresh foods. However, environmental conditions and intrinsic properties of films influence their release. The aim of this study was to investigate the effect of the concentration and type of encapsulating agent and pH of emulsions on the physical and antimicrobial properties of alginate-carvacrol films. Films containing alginate, carvacrol as antimicrobial agent, and Tween 20 or trehalose (0.25 and 0.75% w/w) as encapsulating agents were obtained from suspensions at pH 4 and pH 8. Physical characterization of emulsions and films and antimicrobial properties (E. coliandB. cinerea) was evaluated. Results showed that droplets size depended on trehalose concentration, but emulsion stability depended on pH and type of encapsulating agent, being more stable samples with trehalose at pH 4. Although films with Tween 20 presented the highest opacity, they showed the best antimicrobial properties at initial time; however, during storage time, they lost their activity before samples with trehalose and relative humidity (RH) was the principal factor to influence their release. Therefore, sample formulated with 0.25% trehalose at pH 4 and stored at 75% RH had the best potential as edible film for fresh fruits.

Characterization of novel ybjG and dacC variants in Escherichia coli

2013 ◽  
Vol 62 (11) ◽  
pp. 1728-1734 ◽  
Author(s):  
Dongguo Wang ◽  
Enping Hu ◽  
Jiayu Chen ◽  
Xiulin Tao ◽  
Katelyn Gutierrez ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Multiple Drug Resistance ◽  
Multiple Drug ◽  
The Novel ◽  
Conventional Pcr ◽  
E Coli ◽  
Novel Variants ◽  
Restriction Sites ◽  
Genetic Structures

A total of 69 strains of Escherichia coli from patients in the Taizhou Municipal Hospital, China, were isolated, and 11 strains were identified that were resistant to bacitracin, chloramphenicol, tetracycline and erythromycin. These strains were PCR positive for at least two out of three genes, ybjG, dacC and mdfA, by gene mapping with conventional PCR detection. Conjugation experiments demonstrated that these genes existed in plasmids that conferred resistance. Novel ybjG and dacC variants were isolated from E. coli strains EC2163 and EC2347, which were obtained from the sputum of intensive care unit patients. Genetic mapping showed that the genes were located on 8200 kb plasmid regions flanked by EcoRI restriction sites. Three distinct genetic structures were identified among the 11 PCR-positive strains of E. coli, and two contained the novel ybjG and dacC variants. The putative amino acid differences in the ybjG and dacC gene variants were characterized. These results provide evidence for novel variants of ybjG and dacC, and suggest that multiple drug resistance in hospital strains of E. coli depends on the synergistic function of ybjG, dacC and mdfA within three distinct genetic structures in conjugative plasmids.

scholarly journals Preparation and Characterization of Chitosan Nanocomposite Based on Nanoscale Silver and Nanomontmorillonite

2019 ◽  
Vol 2 (2) ◽  
pp. 5-12 ◽  
Author(s):  
Fatemeh- Sadat Ebnerasool ◽  
Negar Motakef Kazemi
Keyword(s):  
Food Packaging ◽  
Solution Method ◽  
In Situ Synthesis ◽  
Diffusion Method ◽  
X Ray ◽  
E Coli ◽  
Packaging Industry ◽  
Scanning Electron

The chitosan nanocomposites were rapidly prepared by simple solution method. This biopolymer matrix was modified by prepared nanoscale silver (Ag) using in situ synthesis from precursor and nanomontmorillonite (NMMT). The samples were characterized by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), field emission scanning electron microscopy (FESEM), and energy dispersive x-ray spectroscopy (EDX). The water vapor properties (WVP) of nanocomposites were investigated using gravimetric standard. The antibacterial activity of nanocomposite was measured by the well diffusion method on Muller–Hinton Agar against Escherichia coli (E. coli) by zone inhibition. Based on the obtained results, the nanocomposite can have a good candidate for different applications and food packaging industry.

scholarly journals The production of ecofriendly biofilm with natural oil for food packaging

2020 ◽  
Author(s):  
Emine Arman Kandirmaz ◽  
◽  
Omer Bunyamin Zelzele ◽  
Keyword(s):  
Essential Oil ◽  
Essential Oils ◽  
Shelf Life ◽  
Food Packaging ◽  
Biological Activities ◽  
Uv Spectroscopy ◽  
Antimicrobial Properties ◽  
Active Packaging ◽  
E Coli ◽  
Active Food Packaging

The use of edible biofilms in food packaging reduces the use of petrochemical polymers that are harmful to human health, such as PE, PP, PET. The second most common biopolymer in nature, chitosan is a nontoxic, nonantigenic, biocompatible and biodegradable polymer. Considering these features, it is frequently used in food packaging applications. Increasing needs for food amount and quality canalized food ındustry to fund in new packaging techniques that improve storage life and grade of foods. Active packaging systems, one of these methods, can be designed as a sensor, antimicrobial or antimigrant in order to extend the shelf life of the food product and to inform the shelf life in possible degradation. Essential oils, which are antimicrobial environmentally friendly packaging material additives, are used due to their effective biological activities. Essential oils that have known antimicrobial properties include lavender, rosemary, mint, eucalyptus and geranium. These oils are also edible. In this study, it is aimed to produce antimicrobial, ecofriendly, edible, printable biofilm for active packaging, using chitosan and peppermint essential oil. For this purpose, chitosan biofilms containing different rates (0, 1, 2.5, 5, 10%) of peppermint essential oil were produced by solvent casting method. Surface morphology were examined by SEM. The transparency of biofilms was determined by UV spectroscopy. Antimicrobial properties of the obtained films were determined against S. aureus and E. coli. Biofilms were printed with screen printing. The color, gloss, contact angle, surface tension values of all printed and unprinted samples were examined. As a result, chitosan biofilms which are loaded with peppermint essential oil were successfully produced. Biofilms are colorless, highly transparent and have good printability. It is concluded that the amount of peppermint essential oil increased inhibitory feature against S. aureus and E. coli. When the obtained results are examined, it is determined that the printable, ecofriendly, edible biofilms can be used in active food packaging applications.

scholarly journals Migration of Various Nanoparticles into Food Samples; a Review

Foods ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 2114
Author(s):  
Saeed Paidari ◽  
Reza Tahergorabi ◽  
Ensieh Sadat Anari ◽  
Abdorezza Moahammdi Nafchi ◽  
Nafiseh Zamindar ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Food Industry ◽  
Food Packaging ◽  
Antimicrobial Properties ◽  
Food Samples ◽  
Adverse Impact ◽  
Cell Toxicity ◽  
Inhibitory Effects ◽  
E Coli ◽  
And Migration

Nanotechnology has provided new opportunities for the food industry with its applications in food packaging. The addition of nanoparticles, such as clay, silver and copper, can improve the mechanical and antimicrobial properties of food packaging. However, nanoparticles may have an adverse impact on human health. This has led to legislative and regulatory concerns. The inhibitory effects of nano packaging on different microorganisms, such as Salmonella, E. coli, and molds, have been studied. Nanoparticles, like other materials, may have a diverse set of properties that need to be determined. In this review, different features of silver, clay and copper nanoparticles, such as their anti-microbial, cell toxicity, genetic toxicity, mechanical properties, and migration, are critically evaluated in the case of food packaging. Specifically, the viewpoints of WHO, FDA, and ESFA, concerning the nano-silver application in food packaging, are discussed as well.

scholarly journals Bacteria Exposed to Silver Nanoparticles Synthesized by Laser Ablation in Water: Modelling E. coli Growth and Inactivation

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 653 ◽  
Author(s):  
Lucija Krce ◽  
Matilda Šprung ◽  
Ana Maravić ◽  
Polona Umek ◽  
Krešimir Salamon ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Bacterial Growth ◽  
Growth Curves ◽  
Dynamic State ◽  
Lag Phase ◽  
The Novel ◽  
Minimal Inhibitory Concentrations ◽  
E Coli ◽  
Main Effect

This study is aimed to better understand the bactericidal mode of action of silver nanoparticles. Here we present the production and characterization of laser-synthesized silver nanoparticles along with growth curves of bacteria treated at sub-minimal and minimal inhibitory concentrations, obtained by optical density measurements. The main effect of the treatment is the increase of the bacterial apparent lag time, which is very well described by the novel growth model as well as the entire growth curves for different concentrations. The main assumption of the model is that the treated bacteria uptake the nanoparticles and inactivate, which results in the decrease of both the nanoparticles and the bacteria concentrations. The lag assumes infinitive value for the minimal inhibitory concentration treatment. This apparent lag phase is not postponed bacterial growth. It is a dynamic state in which the bacterial growth and death rates are close in value. Our results strongly suggest that the predominant mode of antibacterial action of silver nanoparticles is the penetration inside the membrane.

scholarly journals Preparation and Characterization of Potato Starch Film with Various Size of Nano-SiO2

Polymers ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1172 ◽  
Author(s):  
Rongfei Zhang ◽  
Xiangyou Wang ◽  
Meng Cheng
Keyword(s):  
Mechanical Properties ◽  
Food Packaging ◽  
Water Resistance ◽  
Gas Permeability ◽  
Potato Starch ◽  
Antibacterial Properties ◽  
E Coli ◽  
Nano Sio2 ◽  
Starch Films

The various sizes (15, 30, 80, and 100 nm) of nano-SiO2/potato starch films were synthesized and characterized. The gas permeability, antibacterial properties, and mechanical properties of the films were evaluated to their potential for application as food packaging materials. Results indicated that the 100 nm nano-SiO2 was well dispersed in the starch matrix, which induced an active group on the surface of 100 nm nano-SiO2 adequately combined with starch macromolecule. The water resistance and mechanical properties of the films were improved with the addition of nano-SiO2. Notably, resistance to ultraviolet and thermal aging was also enhanced. The nano-SiO2/potato starch films were more efficient against Escherichia coli (E. coli) than Staphylococcus aureus (S. aureus). Remarkable preservation properties of the films packaging the white mushrooms were obtained, with those of the 100 nm films considered superior. This study can significantly guide the rational choice of the nano-SiO2 size to meet the packaging requirements of various agricultural products.

scholarly journals Genetic and Kinetic Characterization of the Novel AmpC β-Lactamases DHA-6 and DHA-7

2014 ◽  
Vol 58 (11) ◽  
pp. 6544-6549 ◽  
Author(s):  
Francisco José Pérez-Llarena ◽  
Laura Zamorano ◽  
Frédéric Kerff ◽  
Alejandro Beceiro ◽  
Patricia García ◽  
...  
Keyword(s):  
Enterobacter Cloacae ◽  
Slight Reduction ◽  
The Novel ◽  
Incompatibility Group ◽  
Content Type ◽  
E Coli ◽  
Natural Variants ◽  
Tertiary Protein Structure ◽  
Hydrolysis Of

ABSTRACTDuring a Spanish surveillance study, two natural variants of DHA β-lactamases, DHA-6 and DHA-7, were found, with the replacements Ala226Thr and Phe322Ser, respectively, with respect to DHA-1. The DHA-6 and DHA-7 enzymes were isolated fromEscherichia coliandEnterobacter cloacaeclinical isolates, respectively. The aim of this study was to genetically, microbiologically, and biochemically characterize the DHA-6 and DHA-7 β-lactamases. TheblaDHA-6andblaDHA-7genes were located in the I1 and HI2 incompatibility group plasmids of 87.3 and 310.4 kb, respectively. The genetic contexts ofblaDHA-6andblaDHA-7were similar to that already described for theblaDHA-1gene and included theqnrB4andaadAgenes. The MICs for cephalothin, aztreonam, cefotaxime, and ceftazidime were 8- to 32-fold lower for DHA-6 than for DHA-1 or DHA-7 expressed in the same isogenicE. coliTG1 strain. Interestingly, the MIC for cefoxitin was higher in the DHA-6-expressing transformant than in DHA-1 or DHA-7. Biochemical studies with pure β-lactamases revealed slightly lower catalytic efficiencies of DHA-6 against cephalothin, ceftazidime, and cefotaxime than those of DHA-1 and DHA-7. To understand this behavior, stability experiments were carried out and showed that the DHA-6 protein displayed significantly higher stability than the DHA-1 and DHA-7 enzymes. The proximity of Thr226 to the N terminus in the tertiary protein structure in DHA-6 may promote this stabilization and, consequently, may induce a slight reduction in the dynamic of this enzyme that primarily affects the hydrolysis of some of the bulkiest antibiotics.

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