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In this study, Chia seed mucilage (CSM) as a new source and polyvinly alcohol (PVA) as co-polymer was used to prepare of nanofibers. Different solutions with CSM/PVA volume ratios of 100:0, 80:20, 60:40, 40:60, 20:80, 0:100 were prepared. Results show the increase in the CSM in the polymer solution increased the viscosity, electrical conductivity and viscosity of solution. Scanning electron microscopy (SEM) was to evaluate the morphology of nanofibers. Fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) studies were used to evaluate chemical structure, crystalline structure and thermal characteristics of nanofibers of CSM/PVA. The crystallization index of CSM, PVA, and CSM/PVA nanofibers was 52%, 38%, and 44%, respectively. The non-formation of a new peak and presence of CSM and PVA peaks in the FTIR spectrum of the produced nanofibers are indicative of the lack of chemical reactions between CSM and PVA. Also, the addition of PVA to CSM improves the thermal resistance of the nanofibers. [ABSTRACT FROM AUTHOR]

Introduction: Shrimps are extremely perishable seafoods, which could threaten human health by causing foodborne diseases and intoxications. Therefore, seafood is generally stored at the temperature of -18°C until consumption. The present study aimed to determine the safety of white shrimp in terms of biogenic amine toxicity and investigate some of the rapid chemical indices in this regard. Methods: After preparation, the samples were stored at the temperature of -18°C for six months and analyzed monthly for the levels of trimethylamine nitrogen (TMA-N), biogenic amines (histamine, putrescine, and tyramine), and total volatile base nitrogen (TVB-N). Results: The values of TMA-N and biogenic amines had a rising trend during storage, while TVBN had fluctuated values. Furthermore, putrescine and TMA-N had strong correlation-coefficients with time (r=0.933 and r=0.91, respectively). The biogenic amines remained below the limit value during the six-month storage. Conclusion: Histamine, putrescine, and tyramine did not reach the toxic dose in the study period, posing no significant risk to human health during the appropriate storage of shrimp. Therefore, it is recommended that the values of TMA-N and putrescine be considered as potential quality indicators for frozen white shrimp. [ABSTRACT FROM AUTHOR]

Shigella species and Acanthamoeba castellanii share the same ecological niches, and their interaction has been addressed in a limited number of research. However, there are still uncertain aspects and discrepant findings of this interaction. In the present study, the effects of the bacterial growth phase, cocultivation temperature and the type of culture media on the interaction of A. castellanii with Shigella dysenteriae, Shigella sonnei and Shigella flexneri were evaluated. In nutrient‐poor page's amoeba saline (PAS) medium, the number of recovered bacteria and the uptake rates were significantly higher in stationary phase cells than logarithmic phase cells. However, no significant differences were observed in the number of recovered bacteria and the uptake rates between logarithmic and stationary phase cells in nutrient‐rich peptone–yeast extract–glucose (PYG) medium. While the number of recovered bacteria was significantly higher in nutrient‐rich than nutrient‐poor media, in all the three Shigella species, the bacterial uptake rates were significantly higher in nutrient‐poor than nutrient‐rich media at both cocultivation temperatures. In both nutrient‐poor and nutrient‐rich media and at both cocultivation temperatures, the number of viable Shigella species after 24 h incubation were not influenced by the presence of A. castellanii. Although Shigella species did not proliferate in A. castellanii trophozoites, a considerable number of bacteria were survived in the trophozoites up to 15 days. From the public health perspective, the results of this study are important for further understanding of the nature of the interaction of these organisms and to deal with Shigella species in the environment. [ABSTRACT FROM AUTHOR]

Background and Objective: Raw fish is a highly perishable product that deteriorates due to chemical changes and microbial growth. Biogenic amines (BAs) are generated in course of bacterial spoilage in fish that may lead to BA toxicity, particularly in adverse storage conditions. The purpose of this study was to prevent the BAs toxicity caused by common carp (Cyprinus carpio). Methods: Live Common carps were purchased from a local market. The samples were first divided into control and lactic acid treatment groups, and then stored at 4 C. the concentrations of three BAs were determined (histamine, putrescine and cadaverine) with high performance liquid chromatography equipped with UV detector. Results: Cadaverine and putrescine had the highest concentrations in control group (400.42 and 293.90 mg/kg, respectively). Histamine remained undetectable until the middle of storage period. Histamine and cadaverine concentrations in the lactic acid group were significantly lower compared to that of control group (p < 0.05). Conclusion: The formation of histamine and cadaverine is effectively controlled by lactic acid treatment, although such effect was not observed on putrescine in the entire storage period. [ABSTRACT FROM AUTHOR]

Antioxidants have been widely used as additives to provide protection against oxidative degradation of foods by free radicals. The effect of thyme essence (Zataria multifloraBoiss) on the rancidity development in cobia (Rachycentron canadum) fillets during frozen storage was studied. Cobia fillets were treated with thyme essence (250 and 500 ppm) and then stored at −18°C for up to 6 months. Rancidity development was measured by several biochemical indices including free fatty acids (FFA), peroxide value (PV), thiobarbituric acid (TBA), and complemented by sensory analysis (flesh odor, consistency, and appearance). Also, pH and expressible moisture were measured during 6-month storage. Proximate composition was also determined in the first day. TBA, PV, and FFA levels increased in all treatments due to lipid oxidation. Thyme essence showed an antioxidative effect in cobia fillets during frozen storage as indicated by TBA, PV, and FFA levels. Results showed that FFA, primary and secondary oxidation products, expressible moisture (EM), and pH of thyme essence treated samples were significantly lower than those of the control samples (p< 0.05). Thyme essence retarded oxidative changes in frozen cobia fillets, and the best oxidation inhibition was obtained using thyme essence at 500 ppm. [ABSTRACT FROM PUBLISHER]

Background: The kidney by the way is an essential organ and part of the urinary system and serves as natural filter of blood and removal of wastes, among other functions. The objective of this research is to investigate the effect of caffeine on renal toxicity induced by diethylnitrosamine (DEN), in rats. Materials and Methods: In this experimental study, 40 female rats were divided into 4 groups with 10 animals in each group. Group I (control group), group II were injected with a single dose of DEN (200 mg/kg, i.p.), group III were injected i.p. caffeine (100 mg/kg), daily for 4 weeks, group IV received the same treatment as group 2 of DEN and received daily caffeine as group 3. After 30 days, blood was collected for analyzing level of creatinine and blood urea nitrogen (BUN). Results: The mean serum BUN and creatinine levels were significantly higher in DEN treated control group in comparison to those of base line control. Again, these levels were significantly lower in caffeine pretreated and DEN treated group (groups II, III, IV) when compared to those of DEN treated group (group I). Conclusion: Caffeine may have some nephroprotective effect against DEN induced nephrotoxicity. [ABSTRACT FROM AUTHOR]