fatemeh mohajer

Nowadays, to avoid the use of synthetic preservatives, which do more harm than good, numerous studies are currently focused on using natural ingredients to enhance food product quality and shelf life. Since no study has been conducted on combining coatings with electrolyzed water containing natural antimicrobial compounds, the present study has innovation and priority. In the present study, the effect of chitosan coating prepared through Neutral Electrolyzed Water (NEW) on inhibiting the growth of Escherichia coli O157:H7 inoculated in rainbow trout fillet over 12 days at 4 ˚C was examined.

Fish samples were allocated into six groups following inoculation with E. coli O157:H7 (final concentration: ~ 105 CFU/g). Treatments included control (CON), distilled water (DW), neutral electrolyzed water (NEW), chitosan 2% (CH), chitosan coating prepared by neutral electrolyzed water (CH/NEW), and neutral electrolyzed water followed by chitosan (NEW+CH). Treatments were kept at low temperature (refrigerator) and counting bacteria was done on 0, 1st, 3rd, 6th, 9th, and 12th days. Data analyses were done through repeated measure ANVOA and Bonferroni post hoc tests.

As indicated by the findings, the reduction rate of EW, CH, CH+WE, and CH/EW samples were 1.04, 1.45, 2.01, and 2.02 log CFU/g compared with the CON, respectively. The highest reduction rate was observed in the CH/NEW sample, due to the antimicrobial activity of chitosan and neutral electrolyzed water.

Chitosan coating can be combined with NEW in fish to increase the safety against pathogenic bacteria and E. coli O157:H7. Therefore, it can suggest the use of these natural antimicrobial compounds in the food industry.

Seafood such as fish is an integral part of human nutrition and an excellent source of protein. However, their short shelf life is quite challenging for the food industry.

This study was carried out to investigate the effects of nano-gelatin coating embedded with thymol and nisin on the chemical quality indices of rainbow trout fillets during 16 days of storage at 4°C.

The fillets were randomly divided into six groups, including control (C), gelatin (G), nano-gelatin (NG), nano-gelatin + thymol (NG-T), nano-gelatin + nisin (NG-N), and nano-gelatin + nisin and thymol (NG-T-N). The chemical quality of fish samples was assessed by performing pH, thiobarbituric acid reactive substance (TBARS), peroxide value (PV), free fatty acid (FFA), and total volatile basic nitrogen (TVB-N) analyses every four days.

The results revealed the stunning effect of nisin and thymol addition to the nano-gelatin coating on all chemical quality indices. Besides, PV, TBARS, and FFA analyses showed that nano-gelatin containing thymol significantly decreased lipid oxidation in fish fillet samples (P < 0.05). The lowest amounts of PV (8.33 meq oxygen/kg oil), TBARS, and FFA were recorded for NG-T-N. The best results in the TBARS test (P < 0.05) were observed in NG-T-N, followed by NG-T (1.45 and 1.69 mg of malonaldehyde/kg of tissue, respectively), and similar results were recorded for FFA analysis. On day 16, the lowest amounts of TVB-N were measured for NG-T-N, followed by NG-N and NG-T (26.13, 29.86, and 38.26 mg N/100 g, respectively). Both nisin and thymol reduced the TVB-N and increased the shelf life, and the best results were observed in groups treated with nisin and thymol simultaneously. However, the application of gelatin and nano-gelatin coating without nisin and thymol was ineffective in improving the chemical quality of samples, and they must be used with nisin and/or thymol.

Gelatin nanogel embedded with thymol and nisin can be utilized to enhance the chemical quality and shelf life of fish fillets.

Bivalves are a class of marine mollusks with high nutritional value in addition to various medicinal products. The Persian Gulf is home to 224 species from 29 families of bivalves identified so far. Based on research conducted in the Persian Gulf or other parts of the world, bioactive compounds exist in their shell and soft tissue. In this review article, we reviewed biomedical research related to bivalves. To this end, after classifying the species in the Persian Gulf, articles related to the evaluation of biomedical applications of bivalves in reputable journals in PubMed and Google Scholar databases were included in this study. Research has shown the presence of antioxidant, anti-inflammatory, anti-diabetic, anti-cancer, and anti-microbial compounds in bivalves. They have also been used to produce bioadhesives. Many studies have also used them as biomarkers for monitoring environmental pollution. Due to the species diversity of the Persian Gulf and the biomedical potentials of bivalves, more purposeful and practical research is needed for the production and extraction of medical and health products.

Multifunctional magnetic nanostructures were considered by different functional organic groups to use as a drug delivery arrangement in cancer therapy. The modulating nonmagnetic core-shell, yolk-shell structures, and the MRI-monitored drug release cells were applied in cancer therapy. Furthermore, magneto-fluorescent nanocarriers with fluorescent and superparamagnetic features were used in bioimaging and MRI, respectively.

The aim of this Study was to investigate on the effect of using vegetable oil containing UV absorbent as coating on the weathering resistance of heat treated wood. For this purpose, 180 gr/m2 of vegetable oil (linseed or soybean) containing 0 and 0.5 wt% of UV absorbent (nano ZnO or Tinvin 326) was applied to the surface of the specimens by brush. The weathering resistance of these specimens after six months of natural weathering was examined by colorimetry, roughness, ATR-FTIR spectroscopy and stereomicroscope. The results of colorimetry indicated that in the first month of weathering, coatings containing soybean oil had less color changes than coatings containing linseed oil. But at the end of the weathering, But at the end of the weathering, specimens coated with linseed oil (pure and containing nano ZnO) and soybean oil containing nano ZnO had the least color changes compared to other treatments. The results of the roughness test revealed that the oil coatings have partially reduced surface roughness increasing due to weathering but the UV absorbents did not have a positive effect in this regard. Stereomicroscope images also indicate that coated heat treated wood specimens had less surface degradation and surface crack than uncoated specimens.

A cross-sectional survey was carried out to determine Seroprevalence of Akabane (AKA) and Bluetongue (BT) viruses in industerial dairy herds in Semnan suburbs, Iran. Serum samples were collected from a total of 184 dairy cattle and tested for antibodies against AKAV and BTV using Competitive-ELISA. The prevalence rates of AKAV and BTV antibodies in cattle were 23.3% (0-75% between herds) and 0%, respectively. The prevalence rates of AKAV antibodies were significantly associated with milking statues (milking or heifer) and abortion history, being higher in milking animals in comparison to heifers (31.3%; P < 0.05) and animals without abortion history than previously aborted cattle’s (34.2%; P < 0.05). The study revealed that AKAV infection is rather high prevalent in dairy herds of Semnan suburbs and this calls for control strategy to be noticed by veterinary services while BTV seems to have less importance in cattle herds of region. Key words: Semnan dairy herds, AKABANE, Bluetongue, Seroprevalence, ELISA.