جستجوی مقالات مرتبط با کلیدواژه « آنتی اکسیدان طبیعی » در نشریات گروه « کشاورزی »

The total fat content of the Farmed common carp studied was 13.2%, which is categorized as high fat fish. Considering the amount and type of fish fat, which is unsaturated and long-chain fats and are very vulnerable to the oxidation process, therefore, in order to maintain their quality, artificial or natural preservatives should be used and stored in cold conditions. In this article, common carp was filleted and immersed for 5 min in water extract extracted from mistletoe leaf (Viscum album L.) by percolation method as a natural antioxidant in proportions of 1, 2 and 4%. Then the extract was evaluated in terms of extraction efficiency, phenolic and flavonoid compounds and free radical inhibition (DPPH), and the quality of fillets stored in the refrigerator at time intervals of 0, 4, 8, 12, and 16 days was evaluated with the tests of peroxide values (PV), anisidine value (AV), thiobarbituric acid (TBA), free fatty acids (FFA) and TOTEX amount. The results of extraction efficiency, total phenolic compounds (TPC), flavonoid compounds (TFC), and DPPH were 5.23%, 62.4 mgGA/g E, 34.71 mg QE/g E, and 78.2%, respectively. Also, the values of PV, TBA, FFA, AV, and TOTEX value in the 4% extract treatment were reported as the best treatment on the 16th day of the experiment, 3.42 (meq g O2/Kg Fat), 1.55 (MDA/Kg Fat), 0.85 (OA%), 4.67 and 11.51, respectively. According to these results, mistletoe aqueous extract with a concentration of 4% can be used to delay fat oxidation in farmed common carp.

Iris species are known to be a rich source of isoflavonoids. Iris germanica L. is one of the most important species of bearded irises which is known as Irsa in traditional medicine. In this study, the amount of phenolic compounds and antioxidant activity of the waste obtained during the essential oil extraction process of 34 samples of German iris rhizomes (6 parent samples, 27 hybrid samples and 1 commercial sample) were evaluated. Iris samples were collected from the Ornamental Plants Research Center (OPRC) in Mahallat city and commercial sample were purchased from the market. After extracting the EO, samplings were carried out using the extract in balloon. The phenol content was measured by Folin-Ciocalteu method, flavonoid by Aluminum-chloride method and antioxidant activity with DPPH and FRAP assay. The results of variance analysis showed that all measured factors were affected by the type of hybrid, which was significant in all factors (P<0.01). The results of mean comparison showed that samples with purple and violet flower colors had the highest amount of phenol and flavonoid, followed by the highest level of antioxidant activity. In other words, the highest amount of flavonoid (113.22 mg QUE/g DW plant) and antioxidant activity (DPPH) (817.73 mg TBHQ/gDW plant) was observed in sample P6 (purple parent) and the highest amount of phenol content (261.31 mg GAE/g DW plant) was observed in sample P3 (violet parent). In general, the water residues from the Iris EO extraction can be used as a suitable and cheap source for obtaining natural antioxidants.

In order to increase the oxidative stability of oil, various antioxidants are used. The use of synthetic antioxidants causes concern for the health of consumers due to their carcinogenicity, so today the food industry seeks to use natural alternatives instead of synthetic types to improve the oxidative shelf life of oils. Therefore, the aim of this research was to investigate the possibility of using broccoli sprouts extract (BSE) as a natural antioxidant to develop the oxidative stability of soybean oil. Different levels of BSE, including 200, 400, and 800 ppm, were added to soybean oil and these samples were compared with samples without antioxidants (control) and sample containing TBHQ synthetic antioxidants (100 ppm). Different tests including acid, peroxide, anisidine, totox, thiobarbituric acid (TBA) indexes, and Rancimat number were performed on the oil samples during the accelerated storage period of 18 days at a temperature of 60 °C. The obtained results showed that during the storage period, the values of acid, peroxide, anisidine, totox, and TBA indexes of oil samples increased and the Rancimat number decreased significantly (p<0.05), however, the rate of these changes in the control sample was significantly higher than other samples. Adding BSE and increasing its concentration in the samples significantly reduced the rate of lipid oxidation and triglycerides decomposition in oils (p<0.05), and the highest oxidative stability was observed in the sample containing 800 ppm of BSE. This level of the BSE showed even higher antioxidant activity than the TBHQ synthetic antioxidant. Finally, the results of this study indicated the antioxidant activity of BSE in soybean oil, and therefore, this extract at the level of 800 ppm can be used as a natural antioxidant to develop the oxidative shelf life and stability of soybean oil.

In this study, Alyssum homolocarpum (AH) and Lepidium sativum seed gum (LS) at different ratios 1:0, 1:1, and 0:1 utilized to encapsulate red onion extract (ROE) for beef coating through immersion. Different concentrations of ROE (400, 800, 1200 and 1600 ppm) showed high antioxidant activity due to phenolic and flavonoid compounds. In terms of mean size, the lowest particle size was observed in ROE encapsulated in Alyssum homolocarpum gum (7.4 3 89.3 nm). And nanoemulsions prepared in Lepidium sativum seed gum had higher particle size (145.7 3 2.3 nm). Negative-zeta potential was observed in all nanoemulsions. Meat samples were kept at 4 ° C for 20 days and the values ​​of thiobarbituric acid, color indices L *, a *, b *, total bacterial count were examined at 4-day intervals. The results showed that ROE encapsulated in LS and AH was more effective in delaying the microbial and chemical reactions of coated meat fillets. Due to reduced bacterial growth, decreased thiobarbituric number and microbial growth, shelf life increased from 4 days to 16 days. This study confirmed that ROE encapsulated in the combined coating of AH and LS is a potential coating to improve the quality and shelf life of beef fillets.

Due to undesirable effects of synthetic antioxidants, application of vegetable antioxidants to retard or prevent food oxidation especially oil-based foods is considered. In this study, antioxidant effect of essence and extract of chevil (ferulago angulate) for heat oxidation of sunflower oil was investigated. Effect of essence and extract of chevil on the stability of deodorized sunflower oil at three concentration (0.200,400ppm) by two extraction methods (alcoholic and aqueous extracts) and frying temperatures (160, 170, 180˚c ) as compared to synthetic tertiary buthyl hydroquinone (TBHQ) at 100ppm was studied. Peroxide index, tiobarbituric acid, anisidine totox acidity, and Rancimate stability (100˚c ) were evaluated. The lowest peroxide value, acidity, anisidine value, totox value and tiobarbituric acid was found for 400ppm and the lowest stability was reported for control sample. The highest peroxide, anisidine and totux values, and thiobarbituric acid were related to the control sample, while the sample containing chevil extract (200ppm) had the highest acidity. Chevil essence was better than its ethanolic essence. The best temperature for chemical properties was 160˚c . The results demonstrated the positive effect of chevil essence on the stability of sunflower oil and it, s priority over synthetic antioxidants.

In this study, first extraction from the C. dactylon rhizomes was performed with methanol solvent using maceration method, and total phenolic compounds in the extract were identified and determined. Then the antioxidant effects of the extract in different concentrations (0, 100, 200, 400, 800 and 1000 ppm) on the oxidative stability factors of soybean oil including peroxide value, acidity value, thiobarbituric acid index (TBA) and rancimat value during kept of oil in an oven at 60 °C for 72 hours was evaluated and compared with the synthetic antioxidant BHT (200 ppm). The identification results of phenolic compounds by GC/MS showed that the total amount of phenolic compounds in the C. dactylon rhizomes extract was measured as 917.08 mg/kg and the major phenolic compounds of the extract including Hydroquinone (66.89%), Thymol (1.23%), Levoglucosenone (2.48%) and Vanillic acid (1.35%) were identified. With increasing the concentration of the extract, the amount of polyphenolic compounds and as a result, the free radical scavenging activity of the extract increased. Evaluation of soybean oil stability against oxidation also showed that among the studied concentrations of methanolic extract, the concentration of 1000 ppm due to having the highest amount of phenolic compounds and therefore the highest antioxidant activity, was determined as the most effective concentration level of the extract in increasing the oxidative stability of soybean oil, so that better results were obtained than BHT synthetic antioxidant at a concentration of 200 ppm. Thus, the methanolic extract of the C. dactylon rhizomes can be used as a cheap and available antioxidant source in the edible oils industry.

Triticale is a successful crop of wheat and rye. Ginger has antioxidant and antimicrobial properties. Therefore, the purpose of this study was to produce functional cookies containing triticale flour and ginger powder and essential oil. In the first part of this study, wheat flour (0-50 %) in cookie formula was replaced with triticale. Moisture, firmness, specific volume, porosity, color, and microstructure of cookies were evaluated. In the second part, ginger powder (0-5%) and essential oil (0-150 ppm) were used in the formula and antioxidant, microbial and sensory properties of the cookies were evaluated. In the first part, the sample containing 15% triticale flour had more moisture (14.29%) compared to other samples during one month of storage. The sample containing 15% triticale flour and control had the same specific volume (1.90 cm3 /g), porosity (18.5%) and firmness (4.1 N) and no significant differences were observed between properties of these samples (P<0.05). Antioxidant activity of sample containing 15% triticale flour (control of the second part), sample containing 15% triticale flour and 5% ginger powder and sample containing 15% triticale flour and 150 ppm ginger essential oil  was 4.6, 29.8 and 69.2% respectively. Also, the growth results of mold and yeast showed ginger can be used as an antimicrobial agent and inhibit positive growth in all concentrations of essential oil consumption and at the level of 5% powder. Finally, the highest score of sensory properties was given to the control sample, the sample containing 1 and 3% ginger powder and the sample containing 50 ppm ginger essential oil. Finally, Cookies containing 15% triticale flour in the presence of 3% ginger powder or 50 ppm ginger essential oil can be introduced as the best examples of this research.

The application of natural ingredients in food formulations plays a key role in public health. The application of natural colorants is helpful in human health. Most of the natural colorants have additional roles such as antioxidant or antimicrobial activities. Natural colorants in foods especially in cake formulation, make an attractive view for Childs. In this study, the effects of three natural colorants of lycopene, chlorophyll, and Berberis Vulgaris extracts were investigated in cupcakes. The amounts of 0, 0.5, 1.5, and 2% of extracts were used. The moisture, volume increment, porosity, color parameters, total phenols, antioxidative effects of extracts, and sensory properties were evaluated. Results showed that all-natural colorants increase the final volume, porosity, oxidative stability, phenol content. Also, they reduced the moisture and lipid oxidation of samples. The red, green, and blue parameters of cakes decreased, especially in samples with Berberis Vulgaris extract. The lightness of all samples was significantly reduced after cooking but the lightness of samples with 2% lycopene oleoresin was not high. .Sensory evaluation showed that the color, flavor, and odor of cakes prepared with lycopene, and chlorophyll oleoresin had the highest scores. The cakes prepared with Berberis Vulgaris extract had the lowest scores in color, flavor, and odor, but the texture and porosity were the same as other samples. Finally, it can be concluded that lycopene oleoresin showed significant acceptance, antioxidant effect, and acceptable physical properties. Results can be helpful for researchers and food industries because the lycopene oleoresin showed a significant antioxidant activity after 3 weeks and the total phenols of Berberis Voulgaris extract showed significant stability after 3 weeks. Especially, the panelists have a significant reflection of the colored food. They propose them as an attractive materials for consumption.

The antioxidant effects of red algae (Gracilaria corticata) extract on the quality and shelf life of Scomberomorus guttatus fish fillet in three treatments; two concentrations of (A) 300 ppm and (B) 600 ppm of ethanol extract and one control sample immersed in distilled water without any additive was investigated. The samples were stored at refrigerator (4ºC) for 12 days. The measurements were undertaken at 0, 3, 6, 9 and12 days at the beginning of the experiment. The results showed that the total phenolic content and the ability of the red algae extract to preventthe free radicals were 3.74±0.34 mg Gallic acid/g dry weight of extract and 24.7±2.07%, respectively. Generally, thiobarbituric acid (TBA), total volatile base nitrogen (TVN), free fatty acid (FFA) and pH values were significantly increased and lipid content decreased with storage time, whereas the peroxide value )PV( and moisture content increased at the beginning but decreased at the end of the period (p < 0.05). The treatments maintained better quality in comparison to the control group and A treatment had better antioxidant properties and resulted in the longer shelf life of the product.

Although synthetic antioxidants are effective in stabilizing oils against oxidation, because of their negative effects on the health of consumers, their use are being limited. Therefore, the use of natural antioxidants such as essential oils of some plants is increasing. In this study, the effect of three types of essential oils of  oregano, thyme and rosemary as natural antioxidants at concentrations of  0 (control sample) 250, 500, 750 and 1000 ppm and synthetic antioxidant hydroquinone tertiary butyl (TBHQ) at a concentration of 100 ppm on the oil quality characteristics of Nigella Sative seed oil (OSI index, peroxide value, acidity and thymoquinone content) were evaluated on the extraction days, 30, 60 and 90 days of storage. The results showed that the highest and lowest peroxide values ​​were related to antioxidant-free oil (61.13 meqO2/kg oil) and oil containing 750 ppm rosemary essential oil (7.7 meqO2 / kg oil), respectively. The results also showed that the oil samples did not differ significantly in terms of acidity (p <0.05). Thymoquinone as the active ingredient of the oil was better preserved in oils containing essential oils, so that the highest and lowest values ​​were related to oils containing 750 ppm rosemary essential oil (1684 ppm) and oil without antioxidants (1230 ppm), respectively. In general, the results showed that rosemary essential oil at a concentration of 750 ppm instead of TBHQ can be used to stabilize black seed oil and maintain its properties.

In this study, the essential oil of medicinal plant Satureja khuzestanica was extracted using hydrodistillation method and its total phenol and flavonoids contents, antioxidant property (based on DPPH and ABTS radical scavenging and beta-carotene/linoleic acid assays) and antifungal activity against fungi species causing strawberry rot and mold (Aspergillus niger, Botrytis cinerea, and Rhizopus stolonifer) were investigated. Based on the results of the total phenol and flavonoid contents of the essential oil were 87.23 mg GAE/g and 69.33 mg QE/g, respectively. The antioxidant activity of the essential oil, based on the DPPH radical scavenging, ABTS radical scavenging, and beta-carotene/linoleic acid assays, were 63.29, 58.30 and 51.19%, respectively. The antifungal activity of the essential oil (based on disk diffusion agar, well diffusion agar, and minimum inhibitory/fungicidal concentration) showed that B. cinerea was the most resistant and A. niger was the most sensitive fungal species to the essential oil. The minimum inhibitory concentration for Aspergillus niger, Botrytis cinerea, and Rhizopus stolonifer was 50, 100 and 50 mg/mL, respectively. The minimum fungicidal concentration for Aspergillus niger, Botrytis cinerea, and Rhizopus stolonifer was 200, 400 and 200 mg/mL, respectively.

The Oxidation of oils and fats causes the reduction of their nutritional value and sensory properties. Today, a new approach to the use of natural antioxidants such as essential oils and plant extracts has been developed and used as a desired alternative antioxidants than chemical antioxidants in foods. In this study, ethanolic extracts of walnut green peel (0, 50 and 100% concentrations), different microwave powers (90, 450 and 900 watts) and different extraction time (1, 8 and 15 minutes) were extracted. In order to determine the optimum extract for adding to the oil, the total amount of phenolic compounds and the antioxidant activity of the extracts were measured by Reducing Power assay, scavenging of DPPH radical and total antioxidant capacity. Data analysis showed that optimized extracts were ethanol 53% (extraction time 6 minutes, microwave power 700 watts). Then, different concentrations of optimized extracts (200, 600 and 1000 ppm) were added to soybean oil and were kept in 65°C for the 16 days. The oxidative stability of all treatments was done by evaluation of peroxide value, TBA value, p-anisidin index, totox index and total amount of polar compounds in 0th, 8th and 16th Days of storage and compared with a treatment containing 200 ppm of BHT. The results indicated that different concentrations of optimized ethanolic extracts were effective in oxidation reduction in all treatments (p<0.05). 1000 ppm concentration of ethanolic extract was more effective than BHT and had no adverse effect on color, smell and taste of oil. Thus, the extracts of green walnut peel can be used as natural and effective antioxidant to reduce the oxidation rate of soybean oil.

Oxidation of lipids is one of the main problems in the maintenance and use of edible oils and fats. One of the most effective ways to delay the oxidation of lipids is the use of antioxidants. Adding chemical antioxidants has been shown to cause leukemia or cancer. Therefore, many plants that are excellent sources of phenolic compounds with strong antioxidant activity can be used as a suitable alternative to oxidative stability. In this research, the extract of the leaf Levyticum officinale was done using methanol solvent. The total phenolic compounds in the extract as well as its antioxidant activity were determined by investigating the inhibitory power of DPPH free radicals, then the antioxidant effects of the extract at different concentrations on oxidative stability of soybean oil was evaluated by measuring the peroxide value and the index of thiobarbituric acid (TBA) and the effect of synthetic antioxidant BHT has been compared. The results showed that by increasing the concentration of extract, the amount of phenolic compounds present in the extract increased as a result of its antioxidant activity, with the highest concentration of these compounds in the concentration of 1000 ppm, which was equal to 0.706 mg Ga / gr Extract . The highest antioxidant activity belonged to the highest concentrations of extract (1000 ppm) with 88.59%. Results of the test of peroxide value and TBA index showed that over time, concentrations of 800 ppm and 1000 ppm of the extract could well control the oxidation of soybean oil and would be better than synthetic antioxidant BHT. Therefore, according to the results obtained from this study, the extract of the plant can be used as a source of natural antioxidants to prevent the oxidation of oils and oil-containing foods.

Food industry produces a large amount of onion skin wastes. Due to the high amount of bioactive compounds found in such by-product, developing a method for the recovery of these biological lesions is important to benefit from them as a source of biologically active compounds.  The aims of this research were to compare the two methods, ultrasound and microwave, for extraction the phenolic compounds of red onion skin wastes and also to investigate the drying pre-treatment with conventional or infrared oven. The investigation the total phenolic compounds and anthocyanin content of extracts showed that use of ultrasonic method caused significantly (p < 0.05) enhanced extraction efficacy of phenolic compounds and anthocyanins. Additionally, drying by infrared oven caused significantly (p < 0.05) increase in total phenolic compounds and anthocyanins extraction. The antioxidant activity analysis of extracts showed that antioxidant capacity of samples extracted by ultrasonic method were significantly (p < 0.05) higher than that extracted by microwave method. As a result, the ultrasonic extraction by pretreatment applying infrared oven may be recomended as a suitable technique to extract phenolic compounds found in red onion skins to benefit from the nutritional potential of these biological wastes.

Brown algae are a valuable source of natural antioxidant compounds, especially Phlorotannins. In this study, the effect of solvent concentration (water / ethanol) on the the amount of Phlorotannin compounds and antioxidant properties of extracts from brown alga Sargassum angustifolium were investigated. The extraction was performed by solvent method at room temperature (28-26 °C) with ethanol/ water solvent with three ratios (30:70), (50:50) and (70:30). The amount of Phlorotannin, total phenolic content, ferric reducing antioxidant power, DPPH radical scavenging activity and total antioxidant capacity of different extracts were evaluated. The results showed that the yield of Phlorotannin extraction was dependent on the solvent concentration and with increasing polarity of the solvent, its amount increased, So its amount in ethanol/ water treatment (30:70) is significantly more than the other two treatments (P<0.05). Also, the highest amount of DPPH radical scavenging activity was obtained in ethanol/ water treatments 50:50 and 70:30 which contained less Phlorotannin. Finally, it was found that the ethanol/ water treatment 30:70 of the brown alga Sargassum angustifolium was a good choice for extracting Phlorotannin compounds as a natural bioactive compound for food and medicine purposes.

Oils and fats under the influence of several factors such as oxygen, light, heat, metal ions and enzyme are oxidized. Use of synthetic antioxidants due to the possibility of toxicity and carcinogenicity, has been under questioned. The aim of this study was to optimize the extraction conditions of Ajowan seed extracts and evaluate their antioxidant properties. In this study Ajowan seed under different concentration of solvents (water and ethanol in 0, 50 and 100% concentration), extraction time (0.25, 12 and 24 hours) and different temperatures (20, 50, 80 °C) were prepared. The optimal extraction conditions were defined by response surface methods and extraction was performed at the optimum condition. Then different concentrations (0.2, 0.4 and 0.6%) of optimum extracts were prepared and added to the non- containing antioxidant soybean oil. All treatments were kept under 90 °C for 5 days. Acidic value, peroxide value and thiobarbituric acid (TBA) were performed on each treatment in every day. Data analysis showed that addition of water to the solvent increased phenolic compounds extracts and antioxidant activity. According to the results of the thermal stability of soybean oil, the best results were related to BHT and other higher concentrations of ethanolic extracts. The results of the present study showed that the ethanolic extracts of Ajowan seed can be used as natural antioxidants in the formulation of edible oils.

Due to the extensive use of chemical preservatives to increase the shelf life of foods and the prevalence of colorectal cancer, the demand for natural and safe pharmaceuticals and preservatives has increased. Thus, this study aimed to evaluate the antioxidant and cytotoxic potentials of Foeniculum vulgare essential oil, which has vast applications in the traditional medicine. In this study, the essential oil of F. vulgare was extracted by hydrodistillation method and its chemical constituents were identified quantitatively and tentatively using gas chromatography coupled to mass spectrometry and fourier transform infrared spectroscopy. The total phenol and flavonoid contents of the essential oil and its antioxidant activity (DPPH and ABTS free radicals scavenging activity and β-carotene/linoleic acid bleaching inhibition) were also investigated. The cytotoxic effect of F. vulgare essential oil was evaluated on colon cancer cell lines (HT29) using MTT assay. Anethole (75.61%) was the main chemical compound of F. vulgare essential oil and its absorption peaks were appeared at 1244 and 840 cm-1. The total phenol and flavonoid contents of F. vulgare essential oil were 12.87 mg GAE/g and 39.67 mg QE/g, respectively. The antioxidant capacity of the essential oil, based on DPPH radical scavenging activity, ABTS radical scavenging activity, and β-carotene/linoleic acid bleaching inhibition, were 26.68, 39.57, and 32.38%, respectively. The cytotoxic effect of the essential oil on the colon cancer cells was depended on its concentration. The F. vulgare essential oil could be used as a natural compound to inhibit the oxidation of foods and the prevalence of colorectal cancers.

Due to detrimental effects of synthetic antioxidants, application of natural antioxidants which mainly are extracted from botanical sources, in addition to stabilizing food products will reduce undesirable effects of free radicals and synthetic antioxidants. In this research effect of drying methods and solvent type were evaluated on chemical composition and antioxidant activity of sacred fig. at first fruits were dried in oven (40 and 60 °C) and microwave (400 and 700 W) and two solvents of methanol and ethanol were used for extraction. Total phenol and flavonoid content were measured with folin ciocalteu and aluminum chloride methods respectively. Antioxidant activity were measured using DPPH and ABTS methods. Results showed that the lowest IC50 value was for 60 °C oven and methanol solvent (150.11 ppm for DPPH and 222.9 ppm for ABTS) and the highest value was observed in 400 W microwave and ethanol solvent (455.145 ppm in DPPH and 500.1 ppm for ABTS). The highest total phenol and flavonoid content was seen in extract of 60 °C and methanolic solvent (1032 mg GAE/g extract and 63.31 mg QE/g extract).