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1.
ABSTRACT:  Dried mycelia and mycelia-free broths produced by submerged cultures of  Phellinus igniarius  under optimal culture conditions were extracted using methanol and hot water and investigated for antioxidant properties. Methanolic extracts from dried mycelia (MEM) and mycelia-free broth (MEB) showed significant antioxidant properties for all EC50 values less than 10 mg/mL except for MEB in scavenging effects on DPPH radicals. Hot water extracts from dried mycelia (HWEM) were evidenced by their low EC50 values (<10 mg/mL) to be effective in reducing power, chelating effect on ferrous ions, and scavenging effect on superoxide anions. α-tocopherol was mainly found in MEM and γ-tocopherol in MEB. Ascorbic acid and total flavonoids were abundant in methanolic extracts (MEM + MEB), whereas total phenols were rich in HWEM. An excellent correlation between contents of total phenols and EC50 values was accomplished for antioxidant activity ( R 2= 0.996) and chelating ferrous ions ability ( R 2= 0.922).
Practical Application: In our paper, the products by submerged culture of  Phellinus igniarius  exhibited powerful antioxidant properties. Results told that extracts from fermenting products by  P. igniarius  might be good sources for antioxidant-related functional foods and pharmaceutical industries.  相似文献   

2.
The antioxidant activity of an extract of a marine red alga (Grateloupia filicina) was evaluated in linoleic acid and fish oil induct period oil at 65C. Oxidative stability of the oils was evaluated by employing peroxide value (PV), 2-thiobarbituric acid reactive substances (TBARS), conjugated diene (CD) and weight gain experiments. The algal extract was applied to linoleic acid and fish oil at 0.01, 0.03 and 0.05% and results were compared with those of commercial antioxidants such as butylated hydroxytoluene (BHT), butylated hydroxyanisol (BHA) and α-tocopherol at 0.01 %. Results indicated the ability of the alga extract to inhibit oxidation of linoleic acid and fish oil; at α 0.05%  相似文献   

3.
Pleurotus eous is a pink edible oyster mushroom cultivated in Coimbatore. The aim of present study was to evaluate antioxidant potential of ethyl acetate, methanol, and hot water extracts from P. eous using various in vitro ROS/RNS generated chemical and biological models. Results demonstrated that the graded-dose (2–50 mg/mL) of various extracts markedly scavenged the DPPH, ABTS, and hydroxyl radicals, and showed metal chelating ability, reducing capacity in Fe3+/ferricyanide complex, and ferric reducing antioxidant power assays. In biological models, different extracts were found to inhibit lipid peroxidation in brain and liver homogenate. Total antioxidant activity was high in methanolic extract. Hot water extract showed higher amount of total phenol and methanolic extract showed higher amount of flavonoid as compared to other extracts. Based on EC50 values it can be concluded that the various extracts from P. eous were good in antioxidant properties with methanol and ethyl acetate extracts being more effective. The results of this study showed that various extracts could serve as natural antioxidants owing to their significant antioxidant activity.  相似文献   

4.
The role of antioxidants in preventing nitrosamine ( N -nitroso diethanolamine) formation in shampoos and skin creams and the levels of Bronopol (2-bromo, 2-nitropropane-1, 3-diol) addition in relation to the resultant levels of N -nitroso compounds have been studied.
The addition of 0.05% BHT, α-tocopherol or ascorbate was effective in preventing nitrosamine formation (limit of determination: 2.5 μ g kg-1) in products preserved with 0.01% Bronopol. At 0.05% Bronopol, 0.2% of all three antioxidants was effective in preventing nitrosamine formation but at 0.1% Bronopol only α-tocopherol was effective.
Levels of Bronopol found in shampoo formulations stored for 2 weeks at 37°C with initial concentrations of 0.005-0.1% were reduced by 64-86%, independent of the initial concentration. The levels in skin creams stored for extended periods at ambient temperature with 0.01% Bronopol initially were reduced by, on average, 60%.
High nitrite levels (NO2-) were found in formulations containing 0.01% Bronopol but no antioxidants (200-250 mg kg-1). Detected levels of nitrite in skin cream formulations were greater than could be formed by stoichiometric decomposition of Bronopol. In formulations with both Bronopol and antioxidants the levels of nitrite were considerably reduced. When α-tocopherol rather than BHT or ascorbate was the antioxidant then the nitrite levels were appreciably higher but formation of N -nitroso diethanolamine was no greater.
High nitrite levels correlated with the formation of detectable levels of N -nitroso compounds in the absence of antioxidants.
Le rôle préventif du Bronopol et des antioxygènes dans la formation de la nitrosamine  相似文献   

5.
石榴皮提取物的抗氧化作用研究   总被引:15,自引:0,他引:15  
分别以水、甲醇、丙酮和乙酸乙酯为溶剂,对石榴皮中的多酚进行了提取,得到4种提取物。采用油脂过氧化值(POV)法和二苯三硝基苯肼(DPPH)自由基法研究了提取物的抗氧化活性。结果显示,4种提取物均具有抗油脂过氧化和清除DPPH自由基的能力,其抗氧化活性随添加量的增加而增加。4种提取物中,丙酮提取物的抗油脂过氧化作用最大,其次为水提取物和甲醇提取物,乙酸乙酯提取物的抗油脂过氧化作用最小。当丙酮提取物添加量为猪油质量的0.1%时,其抗油脂过氧化活性接近添加量为0.02%茶多酚或BHT。4种提取物对DPPH自由基的清除能力大小顺序依次为:水提取物、丙酮提取物、甲醇提取物和乙酸乙酯提取物。浓度为0.0175 mg/mL的水提取物对DPPH自由基的清除率高达85.2%,高于BHT,但略低于茶多酚。石榴皮多酚是一种有效的天然抗氧化剂。  相似文献   

6.
Antioxidant activities of ethanol and petroleum ether extracts from Brazilian propolis were determined by α,α-diphenyl-β-picrylhydrazyl (DPPH) radical-scavenging and ferric thiocyanate (FTC) methods, using α-tocopherol and butylated hydroxytoluene (BHT) as references. The DPPH assay showed that ethanol extract possessed significantly higher activity compared with BHT and petroleum ether extract but lower than that of α-tocopherol. Results from the FTC assay indicated that the activity of ethanol extract was higher than that of α-tocopherol and petroleum ether extract but lower than BHT. Basically, this antioxidant activity was dose-dependent and ethanol extract exhibited higher activity than that of petroleum ether extract at the same concentration. Additionally, the chemical constituents of propolis were determined, and results showed that the propolis contained high content of antioxidant compositions, such as flavonoids (73.00 g kg−1), total phenolic compounds (134.40 g kg−1), and Vitamin E (0.16 g kg−1), which contributed greatly to its strong antioxidant activity.  相似文献   

7.
《Food chemistry》2002,78(4):457-461
Extracts from three winter wheat varieties (‘Trego’, ‘Akron’ and ‘Platte’) were evaluated and compared to α-tocopherol for their inhibitory effects on lipid peroxidation in fish oils by measuring the oil stability index (OSI). Free radical scavenging capacities and chelating potencies were also measured to better understand the potential mechanism(s) of their effects on lipid peroxidation. Trego extracts showed the greatest capacity to suppress lipid peroxidation in fish oils. The OSI time of the oil sample containing 600 ppm Trego extract was 2.85 h beyond the control sample containing no antioxidant, which is 3.1 times longer than the OSI time of oil containing 300 ppm tocopherol. Dose effects were observed for Trego extract, but not for Akron or Platte extracts. Furthermore, the higher level of Platte extract corresponded to a shorter OSI time. All three wheat extracts directly reacted with and quenched DPPH radicals and showed chelating activity. Akron extract had the greatest radical scavenging and chelating activities. Neither radical scavenging nor chelating activities of the wheat extracts can explain the relative activities of these extracts on lipid peroxidation in fish oils under the experimental conditions. The results of this study indicate possibility of to developing natural food antioxidants from selected wheat varieties, including Trego hard white winter wheat.  相似文献   

8.
大麦麸皮多酚类提取物抗氧化活性和抗突变性   总被引:4,自引:0,他引:4  
大麦麸皮含有以原飞燕草色素等原花色素为主的多酚类物质。该多酚类提取物和原飞燕草色素具有抑制亚油酸氧化能力,用TBA法和硫氰酸铁法比较,其效果等于或低于BHA和BHT,但高于生育酚和抗坏血酸。与儿茶素类比较,原飞燕草色素对红细胞空壳、微粒体和LDL脂质抗氧化作用及对超氧化物和DPPH自由基消除作用,均优于原矢车菊色素,而与(-)-ECG和(-)-EGCG相当。此外,原飞燕草色素具有比原矢车菊色素更强抑制MNNG和Trp-p-1抗突变性,但略低于(-)-EGCG和(-)-EGC。  相似文献   

9.
The antioxidant activity of chloroform and methanol extract of roots and stems of Rhubarb (Rheum ribes L.), which are used for medicinal purposes and also its fresh stems and petioles are consumed as vegetable, was studied. The antioxidant potential of both extracts of roots and stems were evaluated using different antioxidant tests, namely total antioxidant (lipid peroxidation inhibition activity), DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging, superoxide anion radical scavenging, ferric reducing power, and cupric reducing power (CUPRAC), and metal chelating activities. Total antioxidant activity was also measured according to the β-carotene bleaching method, and all four extracts exhibited stronger activity than known standards, namely butylated hydroxytoluene (BHT) and α-tocopherol. Particularly, higher activity was exhibited by roots with 93.1% and 84.1% inhibitions of chloroform and methanol extracts, while 82.2% and 82.0% inhibitions by stem extracts, respectively. However, both methanol extracts exhibited higher DPPH radical scavenging activity than the corresponding chloroform extracts, moreover, methanol extract of the stems showed better activity than BHT. In addition, both root extracts showed more potent superoxide anion radical scavenging activity than BHT, and comparable with well known radical scavenger l-ascorbic acid. Except chloroform extract of the roots, the other three extracts exhibited better metal chelating activity than quercetin. Also, total phenolic and flavonoid contents in both extracts of the roots and stems of R. ribes were determined as pyrocatechol and quercetin equivalents, respectively.  相似文献   

10.
Mycelia of Marasmiellus sp. (KUM 50061) were grown on maize for antioxidant production. This formed the mycelial biomass which was then extracted with methanol. Antioxidant activity of methanolic extract was analysed by the TBARS assay, using egg yolk or palm cooking oil as a source of lipid, rather than the conventional rat liver microsomes or linoleic acid. Results showed that at low concentrations of extracts, inhibition of lipid peroxidation in buffered egg yolk was marginal, but significant inhibitory response was evident as the concentrations was increased. The concentration of extract of fermented maize that caused 50% inhibition of lipid peroxidation of buffered egg yolk was 6 mg/ml. Results also indicated a decrease in peroxidation in heated cooking oil supplemented with dried extract compared to unsupplemented cooking oil. The concentration range of dried extract supplementation was 0.2–5 mg/ml. Increasing the extract concentration did not significantly alter the inhibition of peroxidation. The inhibition effect was still evident even at the lowest concentration tested, and was found to be better than catechin and BHA. This pattern of observation was consistent over the 12-day period of observation. Therefore, the possibility of substituting synthetic antioxidants such as BHA and BHT, which are known to be carcinogenic, with antioxidants of natural origin is suggested.  相似文献   

11.
ABSTRACT: This study was designed to evaluate the antioxidative effectiveness of ethanol extracts of Rhus verniciflua Stoke (RVE) in frying oil of Yukwa base (rice snack). RVE showed a strong antioxidant activity, but commercial antioxidants — BHA and dl-δ-tocopherol — did not demonstrate a significant ifmprovement over the control treatment (Yukwa bases prepared without any antioxidants and extracted oil from these). In particular, induction period, peroxide value, and acid value of RVE treatment exhibited a higher oxidative stability than that of the other treatments. In addition, the decrease in linoleic acid (C18:2)/palmitic acid (C16:0) ratio was much less than the other treatments. Texture properties (hardness and crispiness) of Yukwa base were not significantly different. Results showed strong antioxidant properties of RVE on Yukwa base during storage.  相似文献   

12.
《Food chemistry》2001,72(3):295-300
The antioxidant activity of methanolic and ethyl acetate extracts from Lavandula vera MM cell culture were evaluated by the Schaal oven test in bulk sunflower oil and by the DPPH radical method. The oil oxidation was followed by measuring the quantity of primary oxidation products (peroxide value). Authentic rosmarinic acid, caffeic acid and BHT were tested in parallel for comparison. Ethyl acetate extract much better protected the oil from oxidation than methanolic extract and its antioxidant efficiency was comparable to that of pure rosmarinic and caffeic acids and much stronger than that of BHT. Both cell culture extracts and the authentic phenolic acids were much stronger scavengers of DPPH free radical than BHT on an equimolar basis.  相似文献   

13.
The contents of total chlorophyll (T-Chl), carotenoids and phenolics compounds were quantified in the biomasses of Ulva lactuca grown either in normal or artificial sea water under indoor conditions. The antioxidant and antibacterial activities of U. lactuca crude organic extracts ( Ulva- COEs) were determined. Thirty-four compounds in Ulva- COEs were characterised by thin layer chromatography and high-performance liquid chromatography. The major compounds were chlorophyll a (Chl a ) (15.60–30.90%) and b (Chl b ) (12.20–14.89%) , 9-cis β-carotene (13.12–14.47%), α-carotene (11.44–11.47%) and all-trans β-carotene (6.16–29.70%, of total carotenoids).The Ulva- COEs exhibited remarkable antioxidant activity, with an IC50 (concentration which causes a 50% of DPPH radical scavenging activity) values ranged from 16.5 and 18.7 μg mL−1, which could be compared with the synthetic antioxidants: α-tocopherol (14.4 μg mL−1), butylated hydroxyanisol (13.1 μg mL−1) and butylated hydroxyltoluene (13.1 μg mL−1). Also, Ulva- COEs exhibited great potential antibacterial activities against six bacterial strains, with minimal inhibitory concentration values ranged from 0.40 to 0.35 mg mL−1.  相似文献   

14.
《Food chemistry》2004,87(3):393-400
The antioxidant activity of water and ethanol extracts of clove (Eugenia carophyllata) buds and lavender (Lavandula stoechas L.) was studied. The antioxidant properties of both extracts of clove and lavender were evaluated using different antioxidant tests; reductive potential, free radical scavenging, superoxide anion radical scavenging and metal chelating activities. The both extracts of clove and lavender exhibited strong total antioxidant activity. At the concentrations of 20, 40, and 60 μg/ml, water extract of clove and lavender showed 93.3%, 95.5%, 97.9%, 86.9%, 92.3%, and 94.8% inhibition on lipid peroxidation of linoleic acid emulsion, respectively. At the same concentrations, ethanol extract of clove and lavender exhibited 94.9%, 95.5%, 98.2%, 92.5%, 93.8%, and 96.5%, respectively. Comparable, 60 μg/ml of standard antioxidant such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and α-tocopherol exhibited 96.5%, 99.2%, and 61.1% inhibition on peroxidation of linoleic acid emulsion, respectively. The both extracts of clove and lavender had effective reductive potential, free radical scavenging, superoxide anion radical scavenging, and metal chelating activities at all tested concentrations (20, 40, and 60 μg/ml). Those various antioxidant activities were compared to standard antioxidants such as BHA, BHT, and α-tocopherol. In addition, total phenolic compounds in the both extracts of clove and lavender were determined as gallic acid equivalent.  相似文献   

15.
This study was designed to determine the ability of esculetin to inhibit lipoxygenase activity in soybean. Lipoxygenase was extracted from ground soybean using 0.1 M Tris-HCl buffer (pH 8.6) and centrifuged at 3000 g for 15 min at 4C. The extract was mixed with different volumes of 0.05M esculetin solutions to provide 1.8 × 10−4M, 3.3 × 10−4M, 4.6 × 10−4M and 5.7 × 10−4M to final assay systems, respectively. Lipoxygenase activity decreased as the concentration of esculetin solution mixed in soybean extract increased. Mixing of 1.8 × 10−4M esculetin solution to soybean extract showed the least inhibition effect and was significantly different from that of 3.3 × 10−4M, 4.6 × 10−4M and 5.7 × 10−4M which inhibited LOX (lipoxygenase)'s activity of soybean extracts. In the study comparing the inhibition abilities for lipoxygenase activity among selected antioxidants, esculetin was significantly better than BHA (butylated hydroxyanisole) and α-tocopherol.  相似文献   

16.
ABSTRACT: The antioxidant efficiency of ascorbic acid, α-tocopherol, Trolox C, and catechin were evaluated for chicken breast meat in a dispersion system at 37 °C. Peroxidation was induced by adding different kinds of initiators. The initiators exhibited the following order of catalytic action: ascorbic acid/Fe2+ > hemoglobin > Cu+/H2O2 > 2,2'-azobis (2-amidinopropane) hydrochloride (AAPH). The antioxidant efficiency of the antioxidants tested depended on their phase distribution and their reactivity to the radicals in various initiation systems. Among the antioxidants tested, catechin was the most effective antioxidant for chicken breast meat oxidation under the experimental conditions.  相似文献   

17.

ABSTRACT

Anthocyanins were extracted from seed coats of black beans (Glycine max[L.]) and the inhibitory effects of anthocyanin extract on pericarp browning and lipid peroxidation of litchi fruit were investigated. Litchi fruit were infiltrated for 3 min with 0 (control) or 50 mg/L of anthocyanin extract at a reduced pressure of 53 kPa, then packed in 0.03 mm thick polyethylene bags, and finally stored at 28C for 6 days. Changes in browning index, contents of anthocyanins and total phenol, peroxidase (POD) activity, levels of relative leakage rate and lipid peroxidation, α,α‐diphenyl‐β‐picrylhydrazy (DPPH) radical scavenging activity and reducing power were evaluated. Application of anthocyanin extract from black bean delayed pericarp browning of litchi fruit during storage, which was associated with reduced POD activity and higher contents of anthocyanins and total phenol. Moreover, the anthocyanin extract was found to have a direct inhibition on the POD activity in vitro. Furthermore, application of the anthocyanin extract apparently reduced lipid peroxidation and relatively maintained membrane integrity, which may account for browning inhibition to an extent. Finally, higher DPPH radical scavenging activity and reducing power of the fruits treated with the anthocyanin extract than control fruits possibly benefited in scavenging free radicals and reducing lipid peroxidation. It is, therefore, suggested that inhibited POD activity and reduced lipid peroxidation by the anthocyanin extract from seed coats of black beans were responsible for the inhibition of pericarp browning of litchi fruits.

PRACTICAL APPLICATIONS

Lipid peroxidation is a major cause of quality deterioration of postharvest fruits and vegetables. Some synthetic antioxidants are beneficial in inhibiting lipid peroxidation. However, considering that synthetic antioxidants, such as butylhydroxyanisole and butylated hydroxytoluene (BHT), have potential toxicity, the use of natural extracts to extend the shelf life of postharvest fruits and vegetables is a tendency. In our previous study, it has been found that anthocyanin extract from litchi pericarp has stronger antioxidant activities or free radical scavenging activities than BHT and ascorbic acid ( Duan et al. 2007 ). In this study, the application of anthocyanin extract from seed coat of black soybean showed reduced lipid peroxidation and pericarp browning. It could be used potentially as a postharvest technology for reducing or replacing the use of other chemicals, but it requires further investigation.  相似文献   

18.
《Food chemistry》2003,83(3):371-382
In this study, antioxidant and antimicrobial activities of water and ethanol extracts of anise (Pimpinella anisum L.) seed (PAS) were investigated. The antioxidant properties of both extracts of PAS were evaluated using different antioxidant tests, including reducing power, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, and metal chelating activities. Twenty μg/ml of water and ethanol extracts exhibited 99.1 and 77.5% inhibition of peroxidation in linoleic acid system, which was greater than the same concentration of α-tocopherol (36.1%). These various antioxidant activities were compared with synthetic antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and α-tocopherol. The water extract of PAS exhibited greater antioxidant capacity than that of ethanol. Antimicrobial activity tests were carried out using disc diffusion methods with 10 microbial species.  相似文献   

19.
Arbutus andrachne L. is widely distributed in Jordan. Tyrosinase is the key enzyme in the biosynthesis of melanin. This preliminary study was carried out to assess the possible anti-tyrosinase activity of A. andrachne extracts. Arbutin, hydroquinone and kojic acid were selected as inhibitor standards. Five different extracts (chloroform, butanol, ethanol, methanol and water) were prepared from A. andrachne stems and their activities were compared with the selected tyrosinase inhibitors. IC50 was measured for both, standard and plant extracts. Among the different extracts, the methanolic extract exhibited the highest anttyrosinase activity with an IC50 value (1 mg mL−1). Furthermore, 9 mg A. andrachne methanolic extract showed 97.49% inhibition of tyrosinase activity. Arbutin, hydroquinone, β-sitosterol and ursolic acid were identified in the different extracts of A. andrachne by thin layer chromatography (TLC) and isolated by preparative TLC from the methanolic and chloroform stem extracts, respectively.  相似文献   

20.
Mary  Omwamba  Qiuhui  Hu 《Journal of food science》2010,75(1):C66-C73
ABSTRACT:  Microwave processing and cooking of foods is a recent development that is gaining momentum in household as well as large-scale food applications. Barley contains phenol compounds which possess antioxidant activity. In this study the microwave oven roasting condition was optimized to obtain grains with high antioxidant activity measured as the ability to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. Antioxidant activity of grains roasted under optimum conditions was assessed based on DPPH radical scavenging activity, reducing power and inhibition of oxidation in linoleic acid system. The optimum condition for obtaining roasted barley with high antioxidant activity (90.5% DPPH inhibition) was found to be at 600 W microwave power, 8.5 min roasting time, and 61.5 g or 2 layers of grains. The roasting condition influenced antioxidant activity both individually and interactively. Statistical analysis showed that the model was significant ( P  < 0.0001). The acetone extract had significantly high inhibition of lipid peroxidation and DPPH radical scavenging activity compared to the aqueous extract and α-tocopherol. The reducing power of acetone extracts was not significantly different from α-tocopherol. The acetone extract had twice the amount of phenol content compared to the aqueous extract indicating its high extraction efficiency. GC-MS analysis revealed the presence of phenol acids, amino phenols, and quinones. The aqueous extract did not contain 3,4-dihydroxybenzaldehyde and 4-hydroxycinnamic acid which are phenol compounds reported to contribute to antioxidant activity in barley grain.  相似文献   

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