Oxidant/Antioxidant Status of Breast Cancer Patients in Pre- and Post-Operative Periods.

BACKGROUND AND OBJECTIVES: The purpose of this study is to evaluate the level of oxidative stress before and after breast cancer surgery. MATERIALS AND METHODS: Malondialdehyde (MDA) level was tested using a thiobarbituric acid (TBA) assay based on the release of a color complex due to TBA reaction with MDA. The glutathione S-transferase (GST) activity was evaluated by enzymatic conjugation of reduced glutathione (GSH) with 1-chloro-2,4-dinitrobenzene. The level of total glutathione (reduced GSH and oxidized GSSG) was detected using a recycling system by 5,5-dithiobis(2-nitrobenzoic acid). The levels of the indices were determined in the serum of 52 patients before surgery, two hours and five days after surgery, and in 42 healthy women. RESULTS: In the patients over 50 years old the level of MDA was higher after surgery in comparison with before surgery, and GST activity was lower in comparison with the control. The GSH + GSSG level in both ages groups after surgery was lower than in the control. Significant differences of MDA level were detected in patients with stage III after surgery compared to the control. The level of GSH + GSSG was significantly lower in the patients with I-III stages compared to the control. CONCLUSION: The most expressed changes demonstrate the significance of MDA as a marker to evaluate oxidative stress in breast cancer patients. The degree of oxidative stress depends on the patient's age and stage of disease.

Investigation of lipid-derived formation of decadien-1-amine, 2-pentylpyridine, and acrylamide in potato chips fried in repeatedly used sunflower oil.

This study aimed to investigate lipid derived formations of decadien-1-amine, 2-pentylpyridine, and acrylamide in potato chips during frying. 2,4-Decadienal, a lipid derived carbonyl, was monitored in repeatedly used sunflower oil at different thermoxidation levels (0, 6, 12, 18, 24 h at 180 °C), and in potato chips prepared in. Formations of decadien-1-amine and 2-pentylpyridine were shown for the first time in potato chips. Frying oil had the highest concentration of 2,4-decadienal after thermal oxidation at 180 °C for 6 h. Expectedly, potato chips fried in this oil contained the highest concentration of 2,4-decadienal (29 mg/kg). There was a positive correlation (r2 = 0.73) between the concentrations of 2,4-decadienal and decadien-1-amine (relative concentration as peak area) formed in potato chips fried in repeatedly used sunflower oil. No 2-pentylpyridine was detected in potato chips fried in unoxidized oil, whereas its concentration ranged between 91 and 154 µg/kg in potato chips fried in oxidized oil. Acrylamide concentration of potato chips ranged between 525 µg/kg (fried in oxidized oil, 12 h) and 722 µg/kg (fried in unoxidized oil). A negative correlation (r2 = 0.70) was observed between the concentrations of 2,4-decadienal and acrylamide in potato chips. The results suggest that reactions of lipid derived carbonyls should be taken into account to understand better the modifcations of amino acids in fried products.

Effect of cold plasma on maintaining the quality of chub mackerel (Scomber japonicus): biochemical and sensory attributes.

BACKGROUND: Atmospheric cold plasma (ACP) has emerged as a potential alternative to traditional methods for non-thermal food decontamination. However, few data are available about ACP treatment for seafood. In this study, dielectric barrier discharge (DBD) was applied to generate CP, and the aim of the study was to investigate the effectiveness of DBD-ACP on improving the quality of chub mackerel on the basis of chemical, microbial and sensory characteristics. RESULTS: The effect of DBD-ACP on the quality of chub mackerel (Scomber japonicus) during storage was examined. Results revealed that the optimal voltage level and exposure time of this treatment were 60 kV and 60 s respectively, and such conditions exhibited excellent inactivation efficacy and weak influence on proximate chemical compositions. Variations in total viable count (TVC), sensory scores and total volatile basic nitrogen (TVB-N) indicated that ACP treatment extended the shelf life of chub mackerel to 14 days, whereas samples without this treatment exceeded the limits of the three parameters after 6 days. The slow development rates of peroxide value (PV) and thiobarbituric acid (TBA) value implied that lipid oxidation was also effectively retarded by ACP exposure. Scanning electron microscopy confirmed that CP could effectively delay the degradation of myofibrillar proteins and enhance the stability of tissue structures. CONCLUSION: The excellent antimicrobial efficacy of ACP treatment makes it a potential and promising alternative to other seafood preservation technology. This is the first report on the application of ACP to seafood, which is essential to perishable food storage. © 2018 Society of Chemical Industry.

Preservative effects of fish gelatin coating enriched with CUR/ßCD emulsion on grass carp (Ctenopharyngodon idellus) fillets during storage at 4 °C.

This study investigated the effects of a novel edible coating combining fish gelatin with curcumin/ß-cyclodextrin (CUR/ßCD) emulsion on the quality of grass carp fillets (GCFs) during storage at 4 °C. For all samples, the quality parameters, including weight loss, pH, total volatile basic nitrogen (TVB-N), peroxide value (PV), thiobarbituric acid (TBA) value, SDS-PAGE, free amino acids (FAA), microbiological (total viable counts (TVC), Pseudomonas counts, yeasts and molds, and H2S-producing bacteria), color and sensorial characteristics, were tested periodically. The coatings containing CUR/ßCD emulsions exhibited better preservative effects than gelatin/ßCD coating. Therefore, fish gelatin coating enriched with CUR/ßCD emulsion can be used as an effective way to maintain the quality of GCF and extend its shelf life during storage at 4 °C.

Some Quality Parameters of Powdered Soups Prepared from Different Fish Species

Abstract In this study, we aim to determine the shelf life of dried and ready to use-powdered soup samples obtained from different types of fish species such as Rainbow trout (Oncorhynchus mykiss), sea bream (Sparusaurata L.) and sea bass (Dicentrarchuc labrax). For this purpose, the chemical (moisture, protein, fat, carbohydrate, ash, pH, Thiobarbituric acid (TBA), Total volatile basic nitrogen (TVB-N), microbiological (total mesophilic aerobic bacteria, total yeast and mold, total coliform, Staphylococcus spp. and Salmonella spp.) and sensory properties of fish soup samples were determined during 6-month storage period. The pH, TBA and TVB-N values of all samples increased during the storage period, but these values were within the consumption limits. Additionally, the microbiological properties of all fish soup samples were found within the consumption limits during storage. As a result, a product has been obtained with high nutritional value and rich with regard to protein, oil, and minerals by adding the fish meat to soup samples. It has been determined that the product quality and shelf life significantly increased by using the boiled product for the production of soup samples.

Avocado Seed: A Comparative Study of Antioxidant Content and Capacity in Protecting Oil Models from Oxidation.

Increasingly, consumers want products containing little or no synthetic compounds. Avocado seeds, which are a residue of the food industry, could be used to obtain extracts with high antioxidant power. In the present study, the most popular radical scavenging methods are presented, establishing a comparison between them, besides working with two different extractions: pure methanol and ethanol⁻water (50:50 v/v). The radical scavenging assay methods ORAC and ABTS were performed, as well as a novel method: the reaction to methoxy radical, as determined by electron paramagnetic resonance (EPR). Peroxide value and thiobarbituric acid reactive compounds (TBARs) were used to monitor the oxidation of avocado seed oil, as well as the power of the avocado seed extract (ASE) to delay oil oxidation by oxidation induction time (OIT) and measured by differential scanning calorimetry (DSC). Radical scavenging methods have values between 1310⁻263 µmol TE/g of mass dissolved for ORAC and ABTS, respectively. The individual contribution of each of the compounds present in the extract was analyzed. The sum of all of them contributed up to 84% of the total radical scavenging activity. The concentration of 0.75% ASE causes a delay in the oxidation that is close to 80%, as measured by OIT. This implies that avocado seed residue may have a use as a natural antioxidant source, providing added value to organic waste.

Developing a machine vision system for simultaneous prediction of freshness indicators based on tilapia (Oreochromis niloticus) pupil and gill color during storage at 4°C.

The study assessed the feasibility of developing a machine vision system based on pupil and gill color changes in tilapia for simultaneous prediction of total volatile basic nitrogen (TVB-N), thiobarbituric acid (TBA) and total viable counts (TVC) during storage at 4°C. The pupils and gills were chosen and color space conversion among RGB, HSI and L∗a∗b∗ color spaces was performed automatically by an image processing algorithm. Multiple regression models were established by correlating pupil and gill color parameters with TVB-N, TVC and TBA (R2=0.989-0.999). However, assessment of freshness based on gill color is destructive and time-consuming because gill cover must be removed before images are captured. Finally, visualization maps of spoilage based on pupil color were achieved using image algorithms. The results show that assessment of tilapia pupil color parameters using machine vision can be used as a low-cost, on-line method for predicting freshness during 4°C storage.

Survey on the effects of electron beam irradiation on chemical quality and sensory properties on quail meat.

INTRODUCTION: Irradiation is one of the intervention strategies for effective control of food-borne pathogen microorganisms, which reduces microbial load and extends the meat shelf life. MATERIALS AND METHODS: This experimental study was carried out on quail meat. Quail meat samples were treated with electron beam irradiation at doses of 0.5, 1, and 3 kGy and stored at 4 ±â€¯1 °C for 15 days. Five days after irradiation, the chemical and organoleptic changes in the quail meat were evaluated for 15 days. Total volatile basic nitrogen and TBA were also measured to investigate chemical changes. RESULTS: Irradiation significantly reduced the amount of total volatile basic nitrogen in irradiated samples. Furthermore, the increase of TBA level was significant in irradiated samples, which had a direct correlation with irradiation dose and storage/shelf life duration. Despite the increase of thiobarbituric acid, irradiation had no significant effect on the sensory properties of quail meat. CONCLUSION: Irradiation of quilt meat resulted in extension of the meat shelf life to at least two weeks at refrigeration temperature by decreasing the corrosion-causing microorganisms and improving microbial quality, while the sensory properties of meat were preserved. Regarding the increase in the oxidation level at high doses of the electron beam and the absence of significant differences in the studied dosages in reducing the total amount of total volatile basic nitrogen, it is recommended to apply electron beam irradiation at doses of 1.5 and 3 kGy to extend the meat shelf life and preserve the quality/health of the quail meat.

Effects of hypertonic saline solution associated to remote ischemic perconditioning in kidney ischemia/reperfusion injury in rats.

PURPOSE:: To evaluate the effects of hypertonic saline solution associated to remote ischemic perconditioning in renal ischemia/reperfusion injury in rats. METHODS:: Twenty five male rats (Wistar) underwent right nephrectomy and were distributed into five groups: Sham group (S); Ischemia/Reperfusion group (I/R) with 30 minutes of renal ischemia; Remote ischemic perconditioning group (Per) with three cycles of 10 minutes of I/R performed during kidney ischemia; Hypertonic saline solution group (HSS) treated with hypertonic saline solution (4ml/kg); remote ischemic perconditioning + Hypertonic saline solution group (Per+HSS) with both treatments. After reperfusion, blood samples were collected for BUN and creatinine serum levels analyzes. TBARS were evaluated in plasma and renal tissue to assess oxidative stress. Kidney histopathological examination were performed. RESULTS:: Per+HSS group showed a lower degree of renal dysfunction in relation to I/R group, whereas the technique of remote ischemic perconditioning isolated or associated with saline solution significantly reduced oxidative stress and histological damage. CONCLUSION:: Remote ischemic perconditioning associated or not to saline solution promoted reduction of acute renal injury induced by ischemia/reperfusion.

The shelf life extension of refrigerated grass carp (Ctenopharyngodon idellus) fillets by chitosan coating combined with glycerol monolaurate.

A novel chitosan-based coating solution was prepared by combining glycerol monolaurate (GML) for shelf life extension of refrigerated grass carp fillets. The control and coated fillets were analyzed periodically for physicochemical (pH, thiobarbituric acid (TBA) value, total volatile basic nitrogen (TVB-N) value, K value, and shear force), microbiological (total viable counts (TVC), psychrophilic bacteria counts (PTC), Pseudomonads and H2S-producing bacteria) and sensorial characteristics. The results showed that chitosan-GML coated samples presented better quality preservation effects than chitosan coating alone. In addition, 2% chitosan enriched with 0.3% GML showed the significant (P<0.05) effectiveness in inhibiting microbial growth, nucleotide breakdown, the formation of alkaline components and texture deterioration, and maintaining sensory acceptability among the groups. These findings confirmed that chitosan coating enriched with GML was a promising method to extend the shelf life of refrigerated fillets.

Effects of hypertonic saline solution associated to remote ischemic perconditioning in kidney ischemia/reperfusion injury in rats

Abstract Purpose: To evaluate the effects of hypertonic saline solution associated to remote ischemic perconditioning in renal ischemia/reperfusion injury in rats. Methods: Twenty five male rats (Wistar) underwent right nephrectomy and were distributed into five groups: Sham group (S); Ischemia/Reperfusion group (I/R) with 30 minutes of renal ischemia; Remote ischemic perconditioning group (Per) with three cycles of 10 minutes of I/R performed during kidney ischemia; Hypertonic saline solution group (HSS) treated with hypertonic saline solution (4ml/kg); remote ischemic perconditioning + Hypertonic saline solution group (Per+HSS) with both treatments. After reperfusion, blood samples were collected for BUN and creatinine serum levels analyzes. TBARS were evaluated in plasma and renal tissue to assess oxidative stress. Kidney histopathological examination were performed. Results: Per+HSS group showed a lower degree of renal dysfunction in relation to I/R group, whereas the technique of remote ischemic perconditioning isolated or associated with saline solution significantly reduced oxidative stress and histological damage. Conclusion: Remote ischemic perconditioning associated or not to saline solution promoted reduction of acute renal injury induced by ischemia/reperfusion.

Quality Evaluation Focusing on Tissue Fractal Dimension and Chemical Changes for Frozen Tilapia with Treatment by Tangerine Peel Extract.

This work aimed to establish an effective approach to evaluate the quality of frozen fish, focusing on changes in fish tissue structure and chemical composition during storage. Fresh tilapia samples were treated by coating with tangerine peel (TP) extract and then stored at -4, -8 and -18 °C, respectively, for 40 days. The frozen fish tissues were analyzed for structural and chemical changes. Fractal dimension, which quantifies the porous structure formed in the tissue samples, texture properties including hardness and springiness, and moisture content and water activity all decreased during the storage, while the extents of lipid oxidation, measured as peroxide value and thiobarbituric acid concentration, and protein degradation, monitored with total volatile basic nitrogen and trichloroacetic acid soluble peptides, increased. The change rates of these parameters decreased with decreasing the storage temperature and by applying TP extract. A model was developed for predicting fractal dimension, which indicated the quality of preserved tilapia and thus can be used to predict the shelf life under different storage temperatures. The results demonstrated that TP extract could extend the shelf life of frozen tilapia by 35-45% by inhibiting changes in tissue structure, moisture loss, lipid oxidation and protein degradation during frozen storage.

Shelf-life extension of Pacific white shrimp using algae extracts during refrigerated storage.

BACKGROUND: Shrimp is a low-fat, high-protein aquatic product, and is susceptible to spoilage during storage. To establish an effective method for the quality control of Pacific white shrimp, the effects of polyphenols (PP) and polysaccharides (PS) from Porphyra yezoensis on the quality of Pacific white shrimp were assessed during refrigerated storage. Pacific white shrimp samples were treated with 5 g L-1 polyphenols, and 8 g L-1 polysaccharides, then stored at 4 ± 1 °C for 8 days. All samples were subjected to measurement of total viable count (TVC), pH, total volatile basic nitrogen (TVB-N), K-value, thiobarbituric acid (TBA), polyphenol oxidase (PPO) activity, and were also assessed by sensory evaluation. RESULTS: The results showed that PP, PS, and the mixture of polyphenols and polysaccharides (PP+PS) could inhibit the increase of total volatile basic nitrogen (TVB-N), thiobarbituric acid (TBA) and K-value, and reduce total viable count (TVC) compared with the control group. PP could also inhibit polyphenol oxidase (PPO) activity. Sensory evaluation proved the efficacy of PP and PS by maintaining the overall quality of Pacific white shrimp during refrigerated storage. Moreover, PP+PS could extend the shelf-life of shrimp by 3-4 days compared with the control group. CONCLUSION: PP+PS could more effectively maintain quality and extend shelf-life during refrigerated storage. © 2016 Society of Chemical Industry.

Can supplemental nitrate in cured meats be used as a means of increasing residual and dietary nitrate and subsequent potential for physiological nitric oxide without affecting product properties?

The effects of formulated sodium nitrate plus supplemental nitrate (SN) from celery juice powder on residual nitrite, residual nitrate, rancidity, microbial growth, color, sensory properties, and proximate composition of frankfurters, cotto salami and boneless ham during storage (1°C) were studied. The products were assigned one of two treatments, which were each replicated twice: control (156ppm sodium nitrite) or SN (156ppm sodium nitrite and 1718ppm sodium nitrate in combination with 2% VegStable 502). Sensory parameters and proximate composition were measured once for each replication. All other analytical measurements were conducted at regular intervals for 97-98days. The SN showed no increase in residual nitrite compared to the control. No changes (P>0.05) were observed in residual nitrate during storage for any of the products. The results showed that addition of SN did not significantly alter most physical, chemical or microbial properties of cured meat products during refrigerated storage, but some product dependent sensory effects were observed.

Detection of malondialdehyde in processed meat products without interference from the ingredients.

Our aim was to develop a method for accurate quantification of malondialdehyde (MDA) in meat products. MDA content of uncured ground pork (Control); ground pork cured with sodium nitrite (Nitrite); and ground pork cured with sodium nitrite, sodium chloride, sodium pyrophosphate, maltodextrin, and a sausage seasoning (Mix) was measured by the 2-thiobarbituric acid (TBA) assay with MDA extraction by trichloroacetic acid (method A) and two high-performance liquid chromatography (HPLC) methods: i) HPLC separation of the MDA-dinitrophenyl hydrazine adduct (method B) and ii) HPLC separation of MDA (method C) after MDA extraction with acetonitrile. Methods A and B could not quantify MDA accurately in groups Nitrite and Mix. Nevertheless, MDA in groups Control, Nitrite, and Mix was accurately quantified by method C with good recovery. Therefore, direct MDA quantification by HPLC after MDA extraction with acetonitrile (method C) is useful for accurate measurement of MDA content in processed meat products.

Antioxidant and anti hyperglycemic role of wine grape powder in rats fed with a high fructose diet.

BACKGROUND: Metabolic syndrome is a growing worldwide health problem. We evaluated the effects of wine grape powder (WGP), rich in antioxidants and fiber, in a rat model of metabolic syndrome induced by a high fructose diet. We tested whether WGP supplementation may prevent glucose intolerance and decrease oxidative stress in rats fed with a high fructose diet. METHODS: Male Sprague-Dawley rats weighing 180 g were divided into four groups according to their feeding protocols. Rats were fed with control diet (C), control plus 20 % WGP (C + WGP), 50 % high fructose (HF) or 50 % fructose plus 20 % WGP (HF + WGP) for 16 weeks. Blood glucose, insulin and triglycerides, weight, and arterial blood pressure were measured. Homeostasis model assessment (HOMA) index was calculated using insulin and glucose values. A glucose tolerance test was performed 2 days before the end of the experiment. As an index of oxidative stress, thiobarbituric acid reactive substances (TBARS) level was measured in plasma and kidney, and superoxide dismutase was measured in the kidney. RESULTS: Thiobarbituric acid reactive substances in plasma and renal tissue were significantly higher when compared to the control group. In addition, the area under the curve of the glucose tolerance test was higher in HF fed animals. Furthermore, fasting blood glucose, plasma insulin levels, and the HOMA index, were also increased. WGP supplementation prevented these alterations in rats fed with the HF diet. We did not find any significant difference in body weight or systolic blood pressure in any of the groups. CONCLUSIONS: Our results show that WGP supplementation prevented hyperglycemia, insulin resistance and reduced oxidative stress in rats fed with HF diet. We propose that WGP may be used as a supplement in human food as well.

Effect of N-acetylcysteine in hearts of rats submitted to controlled hemorrhagic shock.

INTRODUCTION: Pharmacological therapy is a strategy for the prevention of complications associated with ischemia and reperfusion injury that occurs after volume replacement in the treatment of hemorrhagic shock. OBJECTIVE: The aim of this study was to evaluate the effect of N-acetylcysteine associated with fluid resuscitation in cardiac injury in a rat hemorrhagic shock model. METHODS: Mice Wister male rats were randomly and subjected to controlled hemorrhagic shock for 60 min. and then, subjected to resuscitation with Ringer lactate. In a group of six animals, 150 mg/kg of N-acetylcysteine were added to fluid volume replacement. The animals were observed for 120 min and after this period, were euthanized and cardiac tissue was collected for histopathological analysis and measurement of thiobarbituric acid reactive substances and pro-and anti-inflammatory interleukin. RESULTS: Cardiac tissue of the group treated with N-acetylcysteine showed lower concentrations of thiobarbituric acid reactive substances (0.20 ± 0.05 vs. 0.27 ± 0.05, P = 0.014) and reduced histopathological damage and edema when compared to the group whose volume replacement occurred only with Ringer lactate. There was no difference in the expression of cytokines interleukin 6 (2,138.29 ± 316.89 vs. 1,870.16 ± 303.68, P = 0.091) and interleukin 10 (1.019,83 ± 262,50 vs. 848.60 ± 106.5, P = 0.169) between the treated groups. CONCLUSION: The association of N-acetylcysteine on volume replacement attenuates oxidative stress in the heart, as well myocardial damage and edema, but does not modify the expression of inflammatory cytokines.

Effect of N-acetylcysteine in hearts of rats submitted to controlled hemorrhagic shock / Efeito da N-acetilcisteína em corações de ratos submetidos ao choque hemorrágico controlado

Abstract Introduction: Pharmacological therapy is a strategy for the prevention of complications associated with ischemia and reperfusion injury that occurs after volume replacement in the treatment of hemorrhagic shock. Objective: The aim of this study was to evaluate the effect of N-acetylcysteine associated with fluid resuscitation in cardiac injury in a rat hemorrhagic shock model. Methods: Mice Wister male rats were randomly and subjected to controlled hemorrhagic shock for 60 min. and then, subjected to resuscitation with Ringer lactate. In a group of six animals, 150mg/kg of N-acetylcysteine were added to fluid volume replacement. The animals were observed for 120 min and after this period, were euthanized and cardiac tissue was collected for histopathological analysis and measurement of thiobarbituric acid reactive substances and pro-and anti-inflammatory interleukin. Results: Cardiac tissue of the group treated with N-acetylcysteine showed lower concentrations of thiobarbituric acid reactive substances (0.20±0.05 vs. 0.27±0.05, P=0.014) and reduced histopathological damage and edema when compared to the group whose volume replacement occurred only with Ringer lactate. There was no difference in the expression of cytokines interleukin 6 (2,138.29±316.89 vs. 1,870.16±303.68, P=0.091) and interleukin 10 (1.019,83±262,50 vs. 848.60±106.5, P=0.169) between the treated groups. Conclusion: The association of N-acetylcysteine on volume replacement attenuates oxidative stress in the heart, as well myocardial damage and edema, but does not modify the expression of inflammatory cytokines. .

Resumo Introdução: A terapia farmacológica é uma estratégia de prevenção das complicações associadas à lesão de isquemia e reperfusão tecidual que ocorre após a reposição volêmica no tratamento do choque hemorrágico. Objetivo: O objetivo deste estudo foi avaliar a repercussão da N-acetilcisteína associada à reposição volêmica na lesão cardíaca em modelo de choque hemorrágico em ratos. Métodos: Ratos Wistar, machos, foram randomizados e submetidos ao choque hemorrágico controlado por 60 minutos e, depois, submetidos à reposição volêmica com Ringer Lactato. Em um grupo de seis animais, foram adicionados 150 mg/Kg de N-acetilcisteína ao fluido de reposição volêmica. Os animais foram observados por 120 minutos e após este período foram submetidos à eutanásia e coleta do tecido cardíaco para análise histopatológica e dosagem de substâncias reativas ao ácido tiobarbitúrico e interleucinas pró e anti-inflamatórias. Resultados: Foi observada menor concentração de substâncias reativas ao ácido tiobarbitúrico (0,20±0,05 vs. 0,27±0,05, P=0,014) e menor dano histopatológico e edema no tecido cardíaco do grupo tratado com N-acetilcisteína em relação ao grupo cuja reposição volêmica ocorreu somente com Ringer Lactato. Não foi observada diferença da expressão das citocinas interleucina 6 (2.138,29±316,89 vs. 1.870,16±303,68, P=0,091) e interleucina 10 (1.019,83±262,50 vs. 848,60±106,5, P=0,169) entre os grupos tratados. Conclusão: A associação da N-acetilcisteína na reposição volêmica atenua o estresse oxidativo no coração, assim como dano e edema miocárdicos, porém, não modifica a expressão de citocinas inflamatórias. .

Preparation of a porcine plasma protein composite film and its application.

To use blood released from slaughtering houses, a porcine plasma protein (PPP)/nanoclay composite film was prepared. The tensile strength and elongation at break values of the PPP composite film with 5% nanoclay were 10.01 MPa and 6.55%, respectively. The PPP composite film containing 1% grapefruit seed extract (GSE) was applied to pork meat, and the populations of inoculated Escherichia coli O157:H7 and Listeria monocytogenes in the pork meat packaged with the PPP composite film decreased by 0.8 and 1.0 log CFU/g, respectively, after 7 days of storage compared to the populations of the control. In addition, thiobarbituric acid values in the pork meat packaged with the PPP composite film were less than those of the control sample during storage. These results suggest that the PPP nanocomposite film containing 1% GSE can be used as a packaging material to maintain the quality of pork meat.

Antioxidant and anti hyperglycemic role of wine grape powder in rats fed with a high fructose diet

BACKGROUND: Metabolic syndrome is a growing worldwide health problem. We evaluated the effects of wine grape powder (WGP), rich in antioxidants and fiber, in a rat model of metabolic syndrome induced by a high fructose diet. We tested whether WGP supplementation may prevent glucose intolerance and decrease oxidative stress in rats fed with a high fructose diet. METHODS: Male Sprague-Dawley rats weighing 180 g were divided into four groups according to their feeding protocols. Rats were fed with control diet (C), control plus 20 % WGP (C + WGP), 50 % high fructose (HF) or 50 % fructose plus 20 % WGP (HF + WGP) for 16 weeks. Blood glucose, insulin and triglycerides, weight, and arterial blood pressure were measured. Homeostasis model assessment (HOMA) index was calculated using insulin and glucose values. A glucose tolerance test was performed 2 days before the end of the experiment. As an index of oxidative stress, thio-barbituric acid reactive substances (TBARS) level was measured in plasma and kidney, and superoxide dismutase was measured in the kidney. RESULTS: Thiobarbituric acid reactive substances in plasma and renal tissue were significantly higher when compared to the control group. In addition, the area under the curve of the glucose tolerance test was higher in HF fed animals. Furthermore, fasting blood glucose, plasma insulin levels, and the HOMA index, were also increased. WGP supplementation prevented these alterations in rats fed with the HF diet. We did not find any significant difference in body weight or systolic blood pressure in any of the groups. CONCLUSIONS: Our results show that WGP supplementation prevented hyperglycemia, insulin resistance and reduced oxidative stress in rats fed with HF diet. We propose that WGP may be used as a supplement in human food as well.