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In this study, the diet contains ascorbic acid at a concentration of 100, 400, 1600 mg kg astaxanthin concentrations of 40, 60 and 100 mg per kilogram of meat lasting quality rainbow trout were studied. The study on 210 rainbow trout with an average weight of about 100 g was performed in seven groups. To study of the process in change and compare the quality of the samples with chemical indicators such as Peroxide (PV), Thiobarbituric acid (TBA) and hydrolysis of lipids (FFA) and PH as well as sensory indicators in five separate time periods of four days (0, 4, 8, 12 and 16) were sampled at ambient temperature in the refrigerator. The results showed that the antioxidant effect and time-consuming amounts of FFA, PH, PV and TBA was significant. Given the significance of the interaction between antioxidants and time can be concluded that the results of the main effects of treatments and time data to all levels of the antioxidant is applied. A total of 1600 samples also contain astaxanthin 100 and ascorbic acid provides the best storage conditions and sensory properties (parameters smell, taste, texture and color) had no significant difference. The results can be used also Organoleptic of the highest astaxanthin and ascorbic acid for use in the diet of fish offered.

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The aim of this study was to extract astaxanthin from banana shrimp (Fenneropenaeus merguiensis) using ultrasound assisted method and to investigate its antioxidant properties. Extraction with organic acetone solvent was performed by soaking on a magnetic stirrer at room temperature for 5, 10, and 15 minutes, as well as neutralization tests of DPPH and ABTS free radicals. Fe³⁺ ion reduction was carried out. One-way analysis of variance was used for statistical analysis of the data. The best astaxanthin yield was 79.5±0.012 µg/g in the conditions of 20 minutes of magnetic stirrer at ambient temperature with 400 watts of ultrasound for 10 minutes, and the lowest average yield was observed in the condition of 15 minutes of magnetic stirrer at ambient temperature with 400 watts of ultrasound with a time of 15 minutes with a value of 69.3±0.049 µg/g. The findings of all three ABTS, DPPH, and Fe3+ ion reduction tests revealed that the settings were 20 minutes of magnetic stirrer at ambient temperature followed by 10 minutes of 400 watts of ultrasound. In summary, the results of this study demonstrated that using ultrasound for a shorter period of time has a better effect, while increasing the time diminishes the yield and antioxidant qualities.

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In this study, the impact of marigold and spirulina, both in isolation and in conjunction with one another, was analyzed on several indicators relating to growth, immunity, survival, and levels of astaxanthin present in zebrafish tissue. 120 zebrafish were randomly allocated to 10 litre aquariums across four different treatment groups (with three replications in each group, each containing 30 fish). The control diet is based on the basic diet, the second treatment diet contains 25 g/kg of spirulina powder (SP) on the basic diet, the third treatment diet contains 25 g/kg of marigold powder (MG) on the basic diet, and the fourth treatment diet It also contains 25 grams of marigold powder (MG) and 25 grams of spirulina (SP+MG)/kg of the basic feed. At the end of the experiment, some immune indicators and astaxanthin were checked in the tissue. The results of this study show the significant effect of spirulina (SP), marigold powder (MG), and the combination of spirulina and marigold powder (SP+MG) on immunity, and astaxanthin. Especially the marigold and the combined treatment of spirulina and marigold showed better performance (P<0.05). respectively, SP+MG and MG treatment significantly increased total protein, lysozyme, and astaxanthin in fish tissue, and the highest amount of IgM was observed in MG treatment (P<0.05). However, no significant difference was observed in relation to growth and survival.

 

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Shrimp by-products can be used as the cheapest raw material to extract bioactive compounds such as lipid extract rich in carotenoid pigments.  The aim of this study was to investigate the nutritional composition of shrimp by-product powder, maximize the extraction efficiency of carotenoid extract using ethanol, hexane, hexane/acetone, and hexane/isopropyl alcohol solvents, and also evaluate the effect of solvent type on the solubility and antioxidant properties of carotenoid extract. According to the results, the shrimp by-product powder contained 53.11% protein, 4.51% moisture, 28.58% ash, 3.45% fat, and 10.45% carbohydrate. The results also showed that using a mixed solvent of hexane/isopropyl alcohol (1:1 ratio) resulted in the highest extraction efficiency of 1.81 g/100 g of dry powder, while the extraction efficiency with ethanol, hexane, and hexane/acetone solvents was 1.53, 1.42, and 1.17 g/100 g of dry powder, respectively. The results of the extract solubility test also showed that the lipid extracted with ethanol solvent has the highest water solubility and the highest antioxidant property (up to 99.10%). In general, the results of this study showed that the use of polar solvents can increase the solubility of carotenoid extract extracted from shrimp by-products and facilitate one of the most important challenges of using this compound in the food and pharmaceutical industries.

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In the present research, after extracting astaxanthin from Haematococcus microalgae and nanoencapsulation it with maltodextrin-sodium caseinate combination coating, carrier nanocapsules with different ratios replaced sodium nitrite (limit of 120 mg/kg) in the sausage formulation. Then, the microbial (Count of mesophilic, psychrophilic, enterobacteriaceae, lactic acid and pseudomonas bacteria) and tissue properties of the formulated sausages were evaluated and compared during the storage period (28 days at refrigerator temperature). The results showed that the treatments that were formulated with ratios of 1 (30 mg/kg) to 3 (90 mg/kg) and 1 (60 mg/kg) to 1 (60 mg/kg) of nanocapsule to sodium nitrite (C and D) have the same efficiency in terms of the ability to inhibit the growth and proliferation of bacterial groups compared to the treatment of 120 mg/kg (A) of sodium nitrite and in the all of storage period, the minimum count of bacteria is related to these treatments. The treatment containing 90 mg/kg of nanocapsules and 30 mg/kg of sodium nitrite (E) had the same ability as treatments A, C and D in inhibiting some bacterial groups until the middle of the storage period. Also, the count level in the treatment containing only nanocapsules (120 mg/kg, B) was significantly lower than the control. The results of measuring the texture characteristics of the treatments showed that the effect of nanocapsules carrying astaxanthin on increasing the water holding capacity of sausages and also reducing of cooking loss, hardness, gumminess, chewiness and tissue cutting is more than sodium nitrite. Springiness, cohesiveness and porosity indices of sausages formulated with different proportions of nanocapsules and sodium nitrite had no significant difference (p>0.05) and were more favorable than the control. In the following, it was found that the texture indicators of the formulated treatments (unlike the control) did not change significantly during the storage period (p>0.05).
 

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The aim of the present research in the first stage was to extract astaxanthin from Haematococcus microalgae (Haematococcus pluvialis) by combined acid-acetone method and evaluate the efficiency of the process. Then, astaxanthin extracted was nanoencapsulated with maltodextrin-sodium caseinate combined coating and physical, antioxidant and color properties of nanocapsules were evaluated along with the pure form of the pigment (during one month of storage at refrigerator temperature). The results showed that with saponification and primary and secondary purification, the efficiency of the extraction process increased and the amount of pigment during the mentioned steps increased from 8.11 to 21.76 mg/g. According to the findings, the size and zeta potential of the produced nanocapsules were 269.1 nm and +46.71 mV, respectively; In addition, the efficiency of the nanoencapsulation process was recorded as 85.19%. The release profile of astaxanthin from nanocapsules in Simulated Gastric Fluid (SGF) and Simulated Intestinal Fluid (SIF) showed that the release of the pigment varies from 3.21 to 14.28 in SGF and from 18.49 to 41.89% in SIF. Based on the results, the DPPH free radical scavenging activity of pure pigment and nanocapsules (at concentrations of 100 and 200 μg/ml and 0, 15 and 30 days) was ranged from about 21 to 57 and 53 to 70%, respectively. This amount for the reduction power of ferric ion was reported from 0.12 to 0.54 and 0.55 to 0.71 absorbance at 700 nm wavelength, respectively. In the metal chelating activity test, the range of changes was recorded from 23 to 52 and 52 to 75%, respectively. With the nanoencapsulation of the pigment and increasing the concentration, its antioxidant activity increased significantly (p<0.05). Also, unlike the pure form of astaxanthin, the antioxidant activity of its carrier nanocapsules remained constant during storage (p>0.05).
 

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The purpose of present study was to use nanocapsules carrying astaxanthin pigment in common sausage formulation as a substitute for sodium nitrite and search for pathogenic and spoilage microorganisms in the product. For this purpose, after extracting astaxanthin from Haematococcus pluvialis microalgae and producing nanocapsules carrying pigment with maltodextrin-sodium caseinate combined coating, five treatments using different proportions of sodium nitrite and nanocapsules carrying astaxanthin along with control were designed and evaluated in term of the presence of Clostridium perfringens, Staphylococcus aureus, coliform, salmonella, Escherichia coli, Clostridium botulinum, lacticacid bacteria bacteria, yeasts and molds during 28 days of storage at refrigerator temperature. The results showed that in the treatment with the permissible limit of sodium nitrite or 120 mg/kg (treatment A) and also the treatments that this limit was replaced by 30 mg/kg (treatment C) and 60 mg/kg (treatment D) of nanocapsules carrying astaxanthin, the counts of Clostridium perfringens, Staphylococcus aureus, and coliform bacteria were within the standard limit and recorded less than 10 cfu/gr. In treatments containing only 120 mg/kg nanocapsules carrying astaxanthin and also containing 30 mg/kg sodium nitrite and 90 mg/kg nanocapsules carrying astaxanthin (treatment E), only on day 28, the counts of three mentioned bacteria were more than 10 CFU/gr. Further, it was found that none of the research treatments contain Salmonella, Escherichia coli and Clostridium botulinum bacteria. Also, all five formulated treatments were within the standard range in terms of lactic acid bacteria during storage time. The results of counting molds and yeasts showed that this treatments, unlike the control sample, did not have any mold and yeast colonies in the whole of storage period. According to the findings of this research if 50% of permissible sodium nitrite limit using nanocapsules carrying astaxanthin is replaced, it is possible to produce a product free of health-threatening microorganisms.
 

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The aim of present research in the first stage was to extract astaxanthin from Haematococcus pluvialis using acid-acetone method and then nanoencapsulation of the pigment using maltodextrin-sodium caseinate coating. In the next step, antioxidant and antibacterial activities of nanocapsules carrying astaxanthin and the free form of the pigment was evaluated. In order to evaluate antibacterial activity of the samples, Listeria monocytogenes, Staphylococcus aureus, Streptococcus iniae, Bacillus subtilis (Gram positive), Yersinia ruckeri, Escherichia coli and Enterobacter aerogenes (Gram negative) were used. The results showed that the antioxidant activity of nanocapsules carrying astaxanthin is significantly higher than the free form of pigment (p<0.05); In addition, this activity was improved by increasing the concentration of samples from 100 to 200 µg/ml (p<0.05). By astaxanthin nanoencapsulation, the diameter of non-growth zone of the studied bacteria increased (p<0.05), but minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the pigment and its carrier nanocapsules decreased (p<0.05). According to the results of zone of inhibition, Gram positive (except Listeria monocytogenes) and Gram negative bacteria were resistant up to concentrations of 60 and 80 µg/ml of samples, respectively. In the following, the MIC and MBC of the pigment (free and nanoencapsulated forms) for the seven bacteria ranged from 50 to 400 and 100 to 500 µg/ml, respectively. The results of evaluation the antioxidant and antibacterial activities of nanocapsules carrying astaxanthin during storage period (30 days at 4ºC) indicated stability and no significant change of these properties (p>0.05). According to the values of diameter of non-growth zone, MIC and MBC, Listeria monocytogenes was the most sensitive bacteria against astaxanthin and its carrier nanocapsules. Based on the findings, astaxanthin extracted from Haematococcus pluvialis has antioxidant and antibacterial activities, and these properties are improved by the pigment nanoencapsulation using maltodextrin-sodium caseinate coating.