Porous Coatings to Control Release Rates of Essential Oils to Generate an Atmosphere with Botanical Actives.

Essential oils have been used in diverse areas such as packaging, agriculture and cosmetics, for their antimicrobial and pesticide activity. The organic volatile compounds of the essential oils are involved in its activity. Controlling their release helps to prolong their functionality. In this study, a functionalized calcium carbonate porous coating was employed to control the release of thyme and rosemary oil in a confined space. The release rate was evaluated at 7 °C and 23 °C, gravimetrically. It was shown that the capillary effect of the porous coating slowed down the release of the volatiles into the headspace compared to the bulk essential oil. A linear drive force model was used to fit the obtained data from both essential oils. The model showed that rosemary reached the asymptotic mass loss equilibrium faster than thyme. This result can be explained by the diverse composition and concentration of monoterpenoids between the two essential oils. Temperature and degree of loading also played important roles in the desorption of the essential oils. It was observed that at high degrees of loading and temperatures the desorption of essential oils was higher. The above-described technology could be used for applications related to food preservation, pest control among others.

Evaluation of the Potential of Modified Calcium Carbonate as a Carrier for Unsaturated Fatty Acids in Oxygen Scavenging Applications.

Modified calcium carbonates (MCC) are inorganic mineral-based particles with a large surface area, which is enlarged by their porous internal structure consisting of hydroxyapatite and calcium carbonate crystal structures. Such materials have high potential for use as carriers for active substances such as oxygen scavenging agents. Oxygen scavengers are applied to packaging to preserve the quality of oxygen-sensitive products. This study investigated the potential of MCC as a novel carrier system for unsaturated fatty acids (UFAs), with the intention of developing an oxygen scavenger. Linoleic acid (LA) and oleic acid (OA) were loaded on MCC powder, and the loaded MCC particles were characterized and studied for their oxygen scavenging activity. For both LA and OA, amounts of 20 wt% loading on MCC were found to provide optimal surface area/volume ratios. Spreading UFAs over large surface areas of 31.6 and 49 m2 g-1 MCC enabled oxygen exposure and action on a multitude of molecular sites, resulting in oxygen scavenging rates of 12.2 ± 0.6 and 1.7 ± 0.2 mL O2 d-1 g-1, and maximum oxygen absorption capacities of >195.6 ± 13.5 and >165.0 ± 2.0 mL g-1, respectively. Oxygen scavenging activity decreased with increasing humidity (37-100% RH) and increased with rising temperatures (5-30 °C). Overall, highly porous MCC was concluded to be a suitable UFA carrier for oxygen scavenging applications in food packaging.

Graphene Derivatives in Biopolymer-Based Composites for Food Packaging Applications.

This review aims to showcase the current use of graphene derivatives, graphene-based nanomaterials in particular, in biopolymer-based composites for food packaging applications. A brief introduction regarding the valuable attributes of available and emergent bioplastic materials is made so that their contributions to the packaging field can be understood. Furthermore, their drawbacks are also disclosed to highlight the benefits that graphene derivatives can bring to bio-based formulations, from physicochemical to mechanical, barrier, and functional properties as antioxidant activity or electrical conductivity. The reported improvements in biopolymer-based composites carried out by graphene derivatives in the last three years are discussed, pointing to their potential for innovative food packaging applications such as electrically conductive food packaging.

Development of antioxidant food packaging materials containing eugenol for extending display life of fresh beef.

In this study, clove essential oil (CL) or eugenol (EU) containing cellulose acetate (CA) or acrylic component/hydrophobically modified starch (AC/S) coatings on corona treated oriented polypropylene film (OPP) were designed and investigated for their possible applications as antioxidant packaging materials for fresh meat. The antioxidant properties of the coatings were investigated by Vapour Phase-DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. The CA coatings containing CL or EU showed 43-92% and 43-94% inhibition against DPPH free radicals through the vapour phase, respectively, whereas AC/S/CL and AC/S/EU coatings resulted in DPPH inhibition of 21-65% and 25-84%, respectively. AC/S/EU and CA/EU coatings on OPP containing from 0.32 ±â€¯0.03 to 6.40 ±â€¯0.14 g/m2 of EU were used to prepare packaging for fresh beef (Longissimus thoracis). After 14 days, the lipid oxidation in beef steaks kept in control and antioxidant packages was 3.33 and 1.00-1.22 mg of malondialdehyde per kilogram of meat, respectively. Moreover, red colour of beef in antioxidant packages was retained.

Active Packaging Applications for Food.

The traditional role of food packaging is continuing to evolve in response to changing market needs. Current drivers such as consumer's demand for safer, "healthier," and higher-quality foods, ideally with a long shelf-life; the demand for convenient and transparent packaging, and the preference for more sustainable packaging materials, have led to the development of new packaging technologies, such as active packaging (AP). As defined in the European regulation (EC) No 450/2009, AP systems are designed to "deliberately incorporate components that would release or absorb substances into or from the packaged food or the environment surrounding the food." Active packaging materials are thereby "intended to extend the shelf-life or to maintain or improve the condition of packaged food." Although extensive research on AP technologies is being undertaken, many of these technologies have not yet been implemented successfully in commercial food packaging systems. Broad communication of their benefits in food product applications will facilitate the successful development and market introduction. In this review, an overview of AP technologies, such as antimicrobial, antioxidant or carbon dioxide-releasing systems, and systems absorbing oxygen, moisture or ethylene, is provided, and, in particular, scientific publications illustrating the benefits of such technologies for specific food products are reviewed. Furthermore, the challenges in applying such AP technologies to food systems and the anticipated direction of future developments are discussed. This review will provide food and packaging scientists with a thorough understanding of the benefits of AP technologies when applied to specific foods and hence can assist in accelerating commercial adoption.

Relationship between IL28B gene rs8099917 polymorphism and SVR in Turkish patients with hepatitis C virus genotype 1.

BACKGROUND AND OBJECTIVE: The hepatitis C virus (HCV) which infects 3% of the world's population is a global challenge. Recently, genome-wide association studies (GWAS) have identified that the IL28B gene rs8099917 polymorphism was associated with the response to the pegylated-interferon alpha/ribavirin (PegIFNα/RBV) combination therapy in patients infected with HCV genotype 1. IL28B gene rs8099917 polymorphism should be determined before beginning treatment of HCV-infected patients to predict an individual's response. The aims of this study were to analyze the correlation between IL28B gene rs8099917 (T/G) polymorphism and PegIFNα/RBV therapy outcome in the Turkish population. METHODS: Genotypes of the IL28B gene rs8099917 (T/G) single nucleotide polymorphism (SNP) were determined in 308 patients with HCV infection by using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. One group consisted of 148 patients with a sustained virological response (SVR), whereas the second group consisted of 160 nonresponders (non-SVR). RESULTS: Allele and genotype associations of IL28B gene rs8099917 polymorphism with a sustained virological response were observed in comparisons between the SVR and non-SVR groups (P<0.001). In addition, the characteristics of the subjects did not differ between these two groups except for age and fibrosis stage (P<0.05). Additionally, neither SVR nor rs80999917 genotypes were associated by HCV RNA levels. CONCLUSIONS: In conclusion, the rs8099917 polymorphism was thus found strongly associated with a sustained virological response to therapy in Turkish patients infected with HCV genotype 1. Consequently, we suggest determining IL28B gene rs8099917 polymorphism of patients with HCV genotype 1 before onset of treatment.

Effect of PON1 gene polymorphisms in Turkish patients with hepatocellular carcinoma.

BACKGROUND: Reactive oxygen species (ROS) can oxidize biological molecules that mediate carcinogenesis by causing metabolic malfunction and damage to DNA. Human serum paraoxonases (PON1, PON2 and PON3) play a role in antioxidant defense and protect the cell against ROS. PON1 polymorphisms Q192R and L55M have been shown to be associated with several human cancers, but their association with hepatocellular carcinoma (HCC) has yet to be investigated. METHODS: We performed genotyping analysis using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay in a hospital-based case-control study of 217 confirmed HCC patients and 217 age-, gender-, smoking- and alcohol consumption-matched cancer-free controls in Turkish population. RESULTS: Q192R and L55M polymorphisms were in significant linkage disequilibrium (LD) (D' = 0.77). However, allele, genotype and haplotype analysis showed no significant differences between the risks of HCC and PON1 polymorphisms. Moreover, no significant differences were found between clinical findings, clinicopathological features and sex in comparison with the PON1 genotypes in HCC group. CONCLUSION: Our results suggest for the first time that neither the Q192R polymorphism nor the L55M polymorphism has relationship with the risk of developing HCC. Further independent studies are required to clarify the possible role of PON1 gene Q192R and L55M polymorphisms on the risk of developing HCC in a larger series and also in patients of different ethnic origins.

Lack of an association of programmed cell death-1 PD1.3 polymorphism with risk of hepatocellular carcinoma susceptibility in Turkish population: a case-control study.

AIM: The programmed cell death-1 (PD-1) is a potent immunoregulatory molecule which is responsible for the negative regulation of T-cell activation and peripheral tolerance. Recently, overexpression of PD-1 has been reported to contribute to immune system evasion and poor survival of hepatocellular carcinoma (HCC). A common single nucleotide polymorphism in intron 4 of PD-1 gene called PD-1.3 has been reported to influence PD-1 expression, but its association with HCC has yet to be investigated. The aim of the present study was to investigate whether this polymorphism could be involved in the risk of HCC susceptibility. METHODS: The genotype frequency of PD-1.3 polymorphism was determined by using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in 236 subjects with HCC and 236 cancer-free control subjects matched on age, gender, smoking and alcohol status. RESULTS: No statistically significant differences were found in the genotype distributions of the PD-1.3 polymorphism among HCC and cancer-free control subjects (P=0.22). CONCLUSION: Our results demonstrate for the first time that the PD-1.3 polymorphism has not been in any major role in genetic susceptibility to hepatocellular carcinogenesis, at least in the population studied here. Independent studies are needed to validate our findings in a larger series, as well as in patients of different ethnic origins.

The significance of Exonuclease 1 K589E polymorphism on hepatocellular carcinoma susceptibility in the Turkish population: a case-control study.

Exonuclease 1 (Exo 1) is an important nuclease involved in mismatch repair system that contributes to maintain genomic stability, to modulate DNA recombination, and to mediate cell cycle arrest. A guanine (G)/adenine (A) common single nucleotide polymorphism at first position of codon 589 in Exo 1 gene determines a glutamic acid (Glu, E) to lysine (Lys, K) (K589E) aminoacidic substitution which may alter cancer risk by influencing the activity of Exo 1 protein. Exo 1 K589E polymorphism has been studied in various cancers, but its association with hepatocellular carcinoma (HCC) has yet to be investigated. To determine the association of the Exo 1 K589E polymorphism with the risk of HCC development in a Turkish population, a hospital-based case-control study was designed consisting of 224 subjects with HCC and 224 cancer-free control subjects matched for age, gender, smoking and alcohol status. The genotype frequency of the Exo 1 K589E polymorphism was determined by using a polymerase chain reaction-restriction fragment length polymorphism assay. Our data shows that the Lys/Lys genotype of the Exo 1 K589E polymorphism is associated with increased risk of HCC development in this Turkish population [odds ratio (OR) = 2.15, 95% confidence interval (CI): 1.13-4.09, P = 0.02]. Furthermore, according to stratified analysis, a significant association was observed between the homozygote Lys/Lys genotype and HCC risk in the subgroups of male gender (OR = 2.67, 95% CI: 1.27-5.61, P = 0.009) and patients with non-viral-related HCC (OR = 3.14, 95% CI: 1.09-8.99, P = 0.03). Because our results suggest for the first time that the Lys/Lys homozygote genotype of Exo 1 K589E polymorphism may be a genetic susceptibility factor for HCC in the Turkish population, further independent studies are required to validate our findings in a larger series, as well as in patients of different ethnic origins.

No association of the exonuclease 1 T439M polymorphism and risk of hepatocellular carcinoma development in the Turkish population: a case-control study.

Exonuclease 1 (Exo 1) is an important nuclease involved in the mismatch repair system that contributes to maintaining genomic stability, modulating DNA recombination and mediating cell cycle arrest. A cytosine (C)/thymine (T) common single nucleotide polymorphism (SNP) at second position of codon 439 in exon 10 of Exo 1 determines a threonine (Thr, T) to methionine (Met, M) (T439M) aminoacidic substitution which may alter cancer risk by influencing the activity of Exo 1 protein. The association of Exo 1 T439M polymorphism with hepatocellular carcinoma (HCC) susceptibility has yet to be investigated. To assess this possibility in a Turkish population, a hospital-based case-control study was designed consisting of 224 subjects with HCC and 224 cancer-free control subjects matched for age, gender, smoking and alcohol status. The genotype frequency of the Exo 1 T439M polymorphism was determined by using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. No statistically significant differences were found in the allele or genotype distributions of the Exo 1 T439M polymorphism among HCC and cancer-free control subjects (P>0.05). Our result demonstrates for the first time that the Exo 1 T439M polymorphism does not have a major role in genetic susceptibility to hepatocarcinogenesis, at least in the population studied here. Independent studies are need to validate our findings in a larger series, as well as in patients of different ethnic origins.

Development of silk fibroin-based beads for immobilized cell fermentations.

Silk fibroin was evaluated as a new matrix for immobilized cell fermentation. Silk fibroin was extracted from Bombyx mori cocoon, purified, concentrated in polyethylene glycol solution and diluted to 3 wt% with distilled water. This fibroin solution was used to encapsulate sensitive cells of the probiotic strain, Bifidobacterium longum ATCC 15707. Polymer droplets produced with an encapsulator were collected in liquid nitrogen and lyophilized. A low overall survival of 0.2% was measured after lyophilization. Lyophilized beads were hardened for 24 h under vacuum with an atmosphere of 89% relative humidity. The inoculated beads were colonized in two successive batch fermentations. Structure of silk fibroin beads and colonization of cells were examined with scanning electron microscopy. Colonized beads were tested in continuous fermentations for cell production. A biomass productivity of 1.7 x 10(9) CFU ml(-1) h(-1) was achieved, which was limited by loss of bead structure. This instability might be due to bead degradation by proteolytic activity of cells and/or limited mechanical stability during continuous fermentation in the stirred tank reactor.

Production of recombinant bacteriocin divercin V41 by high cell density Escherichia coli batch and fed-batch cultures.

To increase the yield of heterologous production of the class II bacteriocin DvnRV41 with Escherichia coli Origami (DE3) (pLysS/pCR03), induction of bacteriocin gene expression was optimized by varying the inducer isopropyl beta-D-thiogalactopyranoside (IPTG) concentration (0-2 mM), and controlled batch and fed-batch cultures were tested on a 2-L scale. A concentration of 0.5 mM IPTG was found to be optimal for cell growth and bacteriocin production. Shake flask cultivation of E. coli Origami (DE3) (pLysS/pCR03) gave biomass and bacteriocin yields of 1.54 +/- 0.06 g cdw/l and 18 +/- 1 mg DvnRV41/l, respectively. Biomass (2.70 +/- 0.06 and 6.8 +/- 0.6 g cdw/l, respectively) and bacteriocin yields (30 and 74 mg DvnRV41 per liter, respectively) were both increased with batch and fed-batch compared to shake flask cultures. Bacteriocin yields reported in this study are among the highest published for other heterologous expression systems in shake flasks.

Fermentation technologies for the production of probiotics with high viability and functionality.

There is growing scientific evidence supported by mechanistic and clinical studies that probiotics can provide health benefits. As probiotics are highly sensitive to many environmental factors, and because the propagation of many strains of intestinal origin is not straightforward, most commercial strains are selected on the basis of their technological properties - ruling out some strains with promising health properties. To date, probiotic production has almost exclusively been carried out using conventional batch fermentation and suspended cultures, in some cases combined with the use of sublethal stresses to enhance cell viability, the addition of protectants or microencapsulation to provide cell protection. However, other less conventional fermentation technologies, such as continuous culture and immobilized cell systems, could have potential for enhancing the performance of these fastidious organisms. These technologies might be employed to develop strains with improved physiology and functionality in the gut and to enlarge the range of commercially available probiotics, as well as expanding product applications.