Nanoparticles based on crocin loaded chitosan-alginate biopolymers: Antioxidant activities, bioavailability and anticancer properties.

Crocin, a water-soluble carotenoid in saffron, is a highly bioactive compound with limited use due to instability to pH variations, heat and oxidative stress, rapid absorption and low bioavailability. In this study, chitosan-alginate nanoparticles, considered as a new vehicle for crocin to improve properties in terms of antioxidant activity, bioavailability and anticancer activity. The swelling of crocin loaded nanoparticles was pH-dependent so that the highest swelling ratio (16g/g) was observed in acidic condition (pH=1.2) after 24h. The antioxidant activity of the crocin loaded nanoparticles was the same effective as pure crocin on DPPH free radical scavenging and ferric reducing ability of plasma (FRAP). In vitro crocin release profile from composite nanoparticles was investigated under simulated physiological conditions during incubation time. The experimental reports collected in this study strongly indicate that nanoparticles loaded with crocin could be the prospective candidates for the future anti-cancer therapeutics that deserve additional investigations.

Improvement of crocin stability by biodegradeble nanoparticles of chitosan-alginate.

This study aimed to improve the stability of crocin, a saffron carotenoid, encapsulating into chitosan (Cs)-sodium alginate (Alg) nanoparticles prepared by a modified ionic gelation method were investigated as a new carrier to improve the stability of crocin. Response surface methodology was used to optimize the important variables, namely the concentrations of Cs and Alg, and pH influencing the particle size, zeta-potential, and encapsulation efficiency to find the optimum formulation for production of crocin nanoparticles (CNPs). Microscopic analysis and dynamic light scattering examination indicated non-smooth and spherical nanoparticles with the size range of 165-230 nm in weight ratio of Cs:Alg (1:1.25) and pH 4.7. Fourier transform-infrared spectroscopy displayed an extensive hydrogen bonding interaction between the crocin and biopolymers. Encapsulation efficiency, loading capacity and yield of CNPs were 38.16, 30.96 and 48.33%, respectively. The zeta-potential of NPs was about -33.52 mV which resulted in the better stability of NPs during manipulation and storage. Stability studies showed that nanoencapsulation provided enhanced crocin stability with biopolymers compared to the standard crocin under unfavorable environmental conditions.

Evaluation of antioxidant activities of bioactive compounds and various extracts obtained from saffron (Crocus sativus L.): a review.

Saffron (Crocus sativus L. stigma), the most valuable medicinal food product, belongs to the Iridaceae family which has been widely used as a coloring and flavoring agent. These properties are basically related to its crocins, picrocrocin and safranal contents which have all demonstrated health promoting properties. The present review article highlights the phytochemical constituents (phenolic and flavonoid compounds, degraded carotenoid compounds crocins and crocetin) that are important in antioxidant activity of saffron extracts. However, the synergistic effect of all the bioactive components presence in saffron gave a significant antioxidant activity similar to vegetables rich in carotenoids. Our study provides an updated overview focused on the antioxidant activity of saffron related to its bioactive compounds to design the different functional products in food, medicine and cosmetic industries.

Effects of storage time on compositional, micro-structural, rheological and sensory properties of low fat Iranian UF-Feta cheese fortified with fish oil or fish oil powder.

The fish oil (FO), and fish oil powder (FOP) at 10 % of recommended daily intake (RDI) were used to make two types of fortified feta cheeses. The physicochemical, rheological and sensory properties of ripened samples at 0, 30, and 60th days of cold store (5 °C) showed that the FO samples had a faster pH reduction, higher MSNF (milk solid non-fat) increase (p < 0.05) and more pores formation. Storage (G') and loss (G") moduli for both samples decreased until the 30th day of cold storage and then increased until the end of the storage time but both of them were higher for FOP samples. The index of secondary lipid oxidation or thiobarbituric acid reactive substances (TBARS) of FO was lower than FOP samples. Although the polyunsaturated fatty acids of both samples were much higher than common feta cheese, their degradation in FO was less than FOP samples after storage. The sensory scores of FO were significantly higher than FOP sample (P < 0.05), and it obtained up to 70 % of overall acceptability after 30 and 60 days storage for its better hardness, texture and flavor.

Effect of autochthonous starter cultures isolated from Siahmazgi cheese on physicochemical, microbiological and volatile compound profiles and sensorial attributes of sucuk, a Turkish dry-fermented sausage.

The effect of adding autochthonous starter cultures isolated from Siahmazgi cheese, on the physicochemical parameters and microbial counts of sucuk was investigated during the ripening period. SPME-GC/MS was used in volatile compound analysis and a trained group of panelists carried out sensory analysis of the final product. After preliminary screening, three strains of Lactobacillus plantarum, which possess desirable technological properties, were used to prepare three starter cultures: LBP7, LBP10 and LBP14. The addition of LBP7 and LBP14 starter cultures had a significant effect (P<0.05) on lightness, leading to higher L values compared to control sausages during the ripening period. Both LBP7 and LBP14 sausages showed higher counts of lactic acid bacteria, lower growth of Enterobacteriaceae and Gram-positive catalase-positive cocci and greatly lowered the pH value compared to control sausages throughout the ripening process. At the end of the ripening process, lactic acid bacteria counts were affected (P<0.05) by the addition of starter culture since higher counts were observed in sausages prepared with LBP7 (9.14logCFU/g) and LBP14 (8.96logCFU/g) batches. The decrease of water activity during the ripening of sausages was not affected by the various starters. The texture profiles of all sausages were similar except for LBP10, which showed lower hardness and gumminess during ripening. Under the conditions of the study, volatile compounds were mainly from spices, and no marked differences were found among inoculated sausages. However, sensory evaluation revealed that most of the sensory attributes were scored higher for inoculated sausages than for the control ones. Therefore, LBP7 and LBP14 could be promising candidates for inclusion as starter cultures for the manufacture of sucuk.

Applying Iranian Gum Tragacanth to Improve Textural Properties of Maltodextrin Microcapsules.

The effects of adding one of the species of Iranian gum tragacanth, Astragalus compactus, to maltodextrin solutions used for microencapsulation of 2-methylbutyl acetate (water-soluble flavoring compound of strawberry) were studied. Initial emulsions were evaluated regarding rheological behavior and particle size distribution. The resulted microcapsules were also analyzed for particle size distributions, glass transition temperature Tg , the morphology of the capsules and the rate of release from them. The results showed that addition of 0.5% w/w A. compactus gum to maltodextrin solutions (14.5% w/w) can increase the viscosity and Tg to an optimum level and can prevent stickiness. Also this species of gum tragacanth had an interesting effect in reducing physical defects of microcapsules and eliminated ruptures significantly. It was also showed that the rate of release of 2-methylbutyl acetate decreased by incorporating gum tragacanth in the wall material. PRACTICAL APPLICATIONS: Microencapsulation is of great interest in preservation of flavoring compounds. One of the most important wall materials is maltodextrin, which has several defects to protect flavorings. This study proposes the use of a new material, Iranian gum tragacanth from Astragalus compactus, to overcome these defects. It was found that new microcapsules did not undergo rupture and could retain the flavoring well.

The first application of a new polysaccharide from Acanthophyllum bracteatum for the health improvement of Atlantic salmon exposed to mercury chloride.

Polysaccharides are biopolymers that play key roles as therapeutic agents. The current study examined the efficiency of a polysaccharide newly derived from a plant resource for detection of sub-acute mercury (Hg) exposure on blood characteristics of Atlantic salmon. The polysaccharide was extracted from the roots of Acanthophyllum bracteatum, and the Atlantic salmon were divided into three groups and placed in fiberglass tanks: one with no Hg as a control, one filled with 60 µg l(-1) of Hg solution, and one with 60 µg l(-1) Hg solution plus 1% weight/weight (w/w) of polysaccharide, which had been added 24 hours before the addition of Hg solution. Serum hematological and biochemical parameters were analysed. Results of the study showed that the blood factors were significantly adjusted in the group that had been exposed to the polysaccharide and Hg compared to the group that had been exposed only to Hg. The polysaccharide had an adjustment effect on lymphocytes, granulocytes, red blood cells (RBCs), Hemoglobin (Hb), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), alanine aminotransferase (ALT), aspartate aminotransferase (AST), protein, chlorine (Cl), sodium (Na), and glucose. It did not have a significant effect on hematocrit (Ht), mean corpuscular hemoglobin concentration (MCHC), potassium (K), and monocytes. Finally, the results confirmed that the new polysaccharide has useful effects on the host, possibly acting as a probiotic by selectively motivating the activity of some useful bacteria, which can improve the host health. This is the first report on application of this polysaccharide for the health improvement of Atlantic salmon exposed to mercury chloride.

Isolation, structural characterization and antioxidant activity of a new water-soluble polysaccharide from Acanthophyllum bracteatum roots.

ABPS-1, a new water-soluble polysaccharide with molecular weight of 26 kDa and a specific optical rotation of +170° (c 1.0, H(2)O), was extracted from the roots of Acanthophyllum bracteatum by warm water and further successively purified through DEAE-cellulose A52 and Sephadex G-100 columns. Monosaccharide analysis revealed that the ABPS-1 was composed of Glc, Gal and Ara with a relative molar ratio of 1.4:5.2:1.0. Its structural features were elucidated by a combination of FT-IR, methylation and GC-MS analysis, periodate oxidation and Smith degradation, partial acid hydrolysis and (13)C and (1)H NMR spectroscopy. The data obtained indicate that ABPS-1 possessed a backbone of α-(1→6)-linked Gal with branches attached to O-2 by α-1→linked Glc and at O-3 by α-1→linked Gal and by α-(1→3)-linked Ara. The in vitro antioxidant activity showed that ABPS-1 possesses DPPH radical-scavenging activity in a concentration-dependent manner with an EC(50) value of 2.6 mg/ml.

Effect of gamma radiation on the quality and shelf life of refrigerated rainbow trout (Oncorhynchus mykiss) fillets.

The effect of gamma radiation (0, 1, 3, and 5 kGy) on the shelf life of farmed rainbow trout (Oncorhynchus mykiss) fillets that were treated with sodium acetate and vacuum packaged and subsequently stored under refrigeration was studied by measuring microbiological, chemical, and organoleptic changes. Radiation affected populations of bacteria, namely, H2S-producing bacteria and Enterobacteriaceae (P < 0.05). Initial total viable counts of the control samples were ca. 4.41 log CFU/g, whereas the respective counts in samples irradiated at 1, 3, and 5 kGy were 3.08, 1.46, and < or = 1 log CFU/g at day 1 of refrigerated storage. The maximum count of Enterobacteriaceae reached 2.29 and 1.45 log CFU/g at the end of storage for 1 and 3 kGy, respectively, but at a 5-kGy dose no growth of Enterobacteriaceae was observed. Of the biochemical indicators, thiobarbituric acid values for irradiated trout were higher than for nonirradiated fish (P < 0.05). Sensory evaluation (taste) showed a reasonable and good correlation with bacterial populations with storage time. The results revealed that radiation at a high dose (5 kGy) might induce lipid and protein oxidation, although the growth of microorganisms was inhibited. Therefore, radiation at a low dose (3 kGy) could be used to control the microbial and safety biochemical indices of O. mykiss for up to 4 weeks at refrigerator temperature without adverse effects on quality and acceptability.