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Curcumin–dextran conjugate was synthesized by free radical grafting reaction between curcumin and dextran. The chemical characterization of the conjugate was obtained by Fourier-transform infrared and 1H-NMR (proton nuclear magnetic resonance) spectroscopy analysis, while the functionalization degree was determined by the Folin–Ciocalteu assay, finding a 22.93 mg of curcumin/g of dextran conjugate. Antioxidant activity of curcumin and curcumin–dextran conjugate was investigated employing DPPH• radical method, and IC50 (the half maximal inhibitory concentration) values of curcumin and the curcumin–dextran conjugate (Cur equivalents) were 86.6 ± 0.1 and 17.4 ± 1 µM, respectively. The presence of dextran into the curcumin–dextran conjugate improved radical scavenging activities of the curcumin. In addition, antimicrobial effect of curcumin and curcumin–dextran conjugate was evaluated against gram-positive ( Listeria monocytogenes and Staphylococcus aureus) and gram-negative ( Escherichia coli O157:H7 and Salmonella typhimurium) bacteria. According to our experiments, gram-positive microorganisms are more sensitive to these compounds than gram-negative ones. Curcumin–dextran is a more potent bacteriostat ( S. aureus (minimum inhibitory concentration = 0.008 µg/mL), E. coli O157:H7 (minimum inhibitory concentration = 250 µg/mL), and S. typhimurium (minimum inhibitory concentration = 500 µg/mL)) and also a more potent bacteriosid against S. aureus and S. typhimurium than curcumin. The cytotoxic effects of the curcumin–dextran conjugate toward AGS, MCF-7, and normal fibroblast cell lines were determined at 48 and 72 h using an MTT assay. The results revealed the considerable antiproliferative effects of the curcumin–dextran conjugate in both AGS and MCF-7 cancer cells in comparison with fibroblast cells. This study shows that dextran as a versatile scaffold develops the biological activities of curcumin by covalent grafting and can be regarded in further bioapplications.

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In this study, the effect of Cuminum cyminum L. essential oil (EO) and Lactobacillus acidophilus (a probiotic) on growth of Staphylococcus aureus in white brined cheese was evaluated. The experiment included different levels of EO (0, 7.5, 15 and 30 µL/100 mL milk) and L. acidophilus (0 and 0.5%) to assess their effects on S. aureus count during the manufacture, ripening and storage of Iranian white brined cheese for up to 75 days. The significant (P < 0.05) inhibitory effects of EO (even at its lowest concentration) and the probiotic on this organism were observed alone and in combination together. Considering the organoleptic evaluation of the EO used in this study, the best inhibitory effect was obtained at combination of EO = 15 µL/100 mL and probiotic = 0.5%. PRACTICAL APPLICATIONS The significant (P < 0.05) synergistic inhibitory effect of the EO and probiotic on S. aureus shown in this study can improve the scope of the EO function in the food industry.

Coccidiosis is the most common parasitic disease of poultry which causes economic damage not only by mortality, but also by impaired growth rate, malabsorption, body weight loss, and the negative effects on the product's yield and quality. This study was conducted to evaluate the effect of dietary supplementation with nanocurcumin on carcass characteristics and physical and chemical properties of broiler chicken breast meat infected with Eimeria acervulina, Eimeria maxima, and Eimeria tenella. Fifty one‐day‐old chicks were randomly assigned to five treatment groups: (1) noninfected/nonmedicated, (2) infected/nonmedicated, (3) infected/medicated (nanocurcumin 300 mg/kg), (4) infected/medicated (nanocurcumin 400 mg/kg), and (5) infected/medicated (antibiotic). Carcass characteristics of Group 3 improved in comparison with Groups 4 and 2, significantly (p < .05). Groups 3 and 4 decreased drip loss and cooking loss and increased protein content in comparison with Group 2. Groups 3 and 4 showed significantly higher a* values in comparison to Group 2 at the first and the 30th day under freeze condition. TBARS value of Group 2 was higher than Group 1, while Group 3 had significantly lower TBARS value than Group 2. SDS‐PAGE patterns and DSC profiles do not show any differences. Nanocurcumin (300 mg/kg) can be used as a potential promising feed additive in poultry production. Practical applications Considering the economic losses due to negative effects of coccidiosis on growth rate and meat quality of broiler chicken, nanocurcumin as a natural and safe food additive can be a promising approach to improve the nutritional value and organoleptic factors of poultry meat during shelf life.

In this study, the chemical and microbiological properties of Siahmazgi cheese, an Iranian artisanal cheese made of unheated ewe and goat milk without addition of starter culture, were evaluated. The pH of the samples ranged from 4.76 to 5.18. The average numbers of total viable count and lactic acid bacteria (LAB) in cheese samples were 3.7 × 10 6 and 6.9 × 10 6 cfu/g, respectively. Coliforms and Enterobacteriaceae were absent in all the samples. A total of 125 LAB isolates were selected according to their Gram-positive and catalase-negative characteristics, out of which 23 strains were cocci and 102 were lactobacilli. Identification of the selected isolates was done through biochemical tests and 16s rDNA sequencing. Isolated strains were identified as Lactobacillus plantarum group (41.6%), Lactobacillus brevis (39.2), Lactobacillus parabuchneri (0.8%), Enterococcus faecium (13.6%), Enterococcus durans (3.2%) and Pediococcus parvulus (1.6%). The results of this study showed the microbiological diversity of traditional Siahmazgi cheese. PRACTICAL APPLICATIONSExploring the microbiological diversity of traditional dairy products is required for selection of appropriate strains to manufacture the products with consistent quality and original taste on industrial scale.

The growth of Vibrio parahaemolyticus (at inoculation levels, 103 and 105 cfu/g) and Listeria monocytogenes (at inoculation level, 103 cfu/g) were investigated in salted fish fillets (brine salted at 4% NaCl) as affected by different concentrations of Zataria multiflora Boiss. essential oil (EO), nisin (N) and their combinations at 8C (and 4C only for L. monocytogenes) during 21 days. The growth of V. parahaemolyticus was inhibited at 8C (in control group) and reached <2 log10 cfu/g at the first day of study for inoculation level of 103 cfu/g. At inoculation level of 105 cfu/g, this inhibitory effect was significantly (P < 0.05) affected by adding EO. The significant inhibitory effect of N alone and synergistic inhibitory effect of EO with N were also observed during the study. For L. monocytogenes, the obvious significant inhibitory effect of EO and its combination with N was observed at 4C. Considering the organoleptic effect of the EO used in this study, the best inhibitory effects of EO in combination with N for V. parahaemolyticus and L. monocytogenes were obtained at combinations of EO = 0.405% and n = 0.75 µg/mL, and EO = 0.405% and n = 0.25 µg/mL, respectively. PRACTICAL APPLICATION The synergistic inhibitory effect of Zataria multiflora Boiss. essential oil and nisin on V. parahaemolyticus and L. monocytogenes, which was obtained in this study can improve the scope of essential oil function in food industry.