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1.
Abstract: GC‐FID and GC‐MS analysis of essential oil from oregano leaves (Origanum compactum) resulted in the identification of 46 compounds, representing more than 98% of the total composition. Carvacrol was the predominant compound (36.46%), followed by thymol (29.74%) and p‐cymene (24.31%). Serial extractions with petroleum ether, ethyl acetate, ethanol, and water were performed on aerials parts of Origanum compactum. In these extracts, different chemical families were characterized: polyphenols (gallic acid equivalent 21.2 to 858.3 g/kg), tannins (catechin equivalent 12.4 to 510.3 g/kg), anthocyanins (cyanidin equivalent 0.38 to 5.63 mg/kg), and flavonoids (quercetin equivalent 14.5 to 54.7 g/kg). The samples (essential oil and extracts) were subjected to a screening for antioxidant (DPPH and ABTS assays) and antimalarial activities and against human breast cancer cells. The essential oil showed a higher antioxidant activity with an IC50= 2 ± 0.1 mg/L. Among the extracts, the aqueous extract had the highest antioxidant activity with an IC50= 4.8 ± 0.2 mg/L (DPPH assay). Concerning antimalarial activity, Origanum compactum essential oil and ethyl acetate extract showed the best results with an IC50 of 34 and 33 mg/mL, respectively. In addition, ethyl acetate extract (30 mg/L) and ethanol extract (56 mg/L) showed activity against human breast cancer cells (MCF7). The oregano essential oil was considered to be nontoxic.  相似文献   

2.
Abstract: The raspberry (Rubus idaeus L.) is an economically important berry crop that contains many phenolic compounds with potential health benefits. In this study, important pomological features, including nutrient content and antioxidant properties, of a domesticated and 3 wild (Yayla, Yavuzlar, and Yedigöl) raspberry fruits were evaluated. Also, the amount of total phenolics and flavonoids in lyophilized aqueous extracts of domesticated and wild ecotypes of raspberry fruits were calculated as gallic acid equivalents (GAEs) and quercetin equivalents (QE). The highest phenolic compounds were found in wild Yayla ecotype (26.66 ± 3.26 GAE/mg extract). Whilst, the highest flavonoids were determined in wild Yedigöl ecotype (6.09 ± 1.21 QA/mg extract). The antioxidant activity of lyophilized aqueous extracts of domesticated and wild ecotypes of raspberry fruits were investigated as trolox equivalents using different in vitro assays including DPPH?, ABTS?+, DMPD?+, and O??2 radical scavenging activities, H2O2 scavenging activity, ferric (Fe3+) and cupric ions (Cu2+) reducing abilities, ferrous ions (Fe2+) chelating activity. In addition, quantitative amounts of caffeic acid, ferulic acid, syringic acid, ellagic acid, quercetin, α‐tocopherol, pyrogallol, p‐hydroxybenzoic acid, vanillin, p‐coumaric acid, gallic acid, and ascorbic acid in lyophilized aqueous extracts of domesticated and wild ecotypes of raspberry fruits were detected by high‐performance liquid chromatography and tandem mass spectrometry (LC‐MS‐MS). The results clearly show that p‐coumaric acid is the main phenolic acid responsible for the antioxidant and radical scavenging activity of lyophilized aqueous extracts of domesticated and wild ecotypes of raspberry fruits.  相似文献   

3.
Higher levels of phenolics were found in steam distilled clove extract (256.5 mg of GAE/g) than its oleoresin (177.1 mg of GAE/g). Antioxidant potential using β-carotene–linoleic acid model of butylated hydroxy anisol, steam distilled and clove oleoresin were 92.39, 85.51, and 77.88%, respectively, at 200 ppm. Radical scavenging activity of butylated hydroxy anisol, extracts of steam distilled and oleoresin were found to be 91.77, 88.93, and 80.84%. Oxidative stability of ghee with butylated hydroxy anisol was highest followed by steam distilled extract and oleoresin throughout 21 days of storage at 80 ± 1°C. During deep frying, steam distilled clove extract had strong antioxidant activity as compared to others.  相似文献   

4.
This study reports the chemical composition, antioxidant, and antimicrobial activity of the essential oil and ethanol extract of Coriandrum sativum L. leaves. Gas chromatography/mass spectrometry analysis identified 19 compounds representing 95.30% of the oil. (E)-2-decenal (29.87%), linalool (21.61%), (E)-2-dodecenal (7.03%), dodecanal (5.78%), (E)-2-undecenal (3.84%), (E)-2-tridecenal (3.56%), (E)-2-hexadecenal (2.47%), tetradecenal (2.35%), and α-pinene (1.64%) were the main components identified in the essential oil. The samples were screened for their antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl radical scavenging and β-caroten bleaching assay. IC50 value for ethanol extract of C. sativum was determined as 74.87 ± 0.03 μg/mL. Total antioxidant activity value for C. sativum ethanol extract was 85.85 ± 0.04%. Total phenolic content for ethanol extract of the plant was determined as 14.97 ± 0.05 mg gallic acid equivalents/g dry weight. The essential oil and ethanol extract were also tested for antimicrobial activity against 28 different foodborne microorganisms, including 19 bacteria, 7 fungi, and 2 yeast species. The ethanol extract of the plant showed weak antimicrobial activities against microbial strains in both disc diffusion and minimal inhibition concentration tests. This study suggested that Coriandrum sativum L. leaves may be used as a potential source of food flavoring, and for their antioxidants and antimicrobial properties.  相似文献   

5.
为充分利用生姜资源,以榨汁后姜渣为原料,采用正交试验方法确定超临界二氧化碳(SCF-CO2)萃取姜渣中姜渣油树脂的最佳工艺条件。结果表明:最佳工艺条件为粉碎粒度50 目、萃取压力25MPa、萃取温度45℃、萃取时间90min。姜渣油树脂在动物油中的抗氧化作用和对1,1- 二苯基-2- 苦基肼(DPPH)自由基的清除作用结果表明,SCF-CO2 萃取的姜渣油树脂具有良好的抗氧化作用。  相似文献   

6.
《Food chemistry》2001,73(2):239-244
The ABTS/H2O2/HRP decoloration method permits the evaluation of the antioxidant activity of complex food samples. This method, with slight modifications, is capable of determining both hydrophilic and lipophilic antioxidant properties, thus, it is possible estimate the antioxidant activity of both antioxidant types in the same sample. The method is easy, accurate and rapid to apply. Its application to three vegetable soups provided data on hydrophilic and lipophilic antioxidant activity, and the values reflect the contribution of the particular antioxidants (ascorbic acid and carotenoids) to the total antioxidant activity of the samples.  相似文献   

7.
Far infrared radiation drying (FIRD) of Ecklonia cava was tried in order to reduce drying time and save money in an industrial processing of wet seaweeds. FIRD was carried out at temperature range of 40–80°C with the examination of antioxidant activities as compared to freeze drying (FD). FIRD showed the shorter drying times and higher polyphenolic contents than FD. Most FIRD extracts had IC50 values than FD extracts. Among them, absolute methanolic extract (ME) from E. cava dried by FIRD at 40°C (FIRD40-ME) possessed the highest radical scavenging activity. Moreover, FIRD40-ME enhanced cell viability and H2O2 scavenging activity in Vero cell. Thus, FIRD40-ME was separated by high performance liquid chromatography (HPLC) and radical scavenging activities of the separated compounds were directly evaluated by on-line coupled ABTS·+ radical scavenging detection system. From the result, it was found that dieckol was the major antioxidant compound. These results illustrate that antioxidant activity of FIRD were more effective than FD and industrial application of FIRD process can be useful in seaweeds.  相似文献   

8.
Dill (Anethum graveolens L.) have been extensively used in salads, soups, and pickles for its aromatic odor and flavor. Recently, interest in plant-derived food additives has grown. In this study, the possible antioxidant properties of water, ethanol, and acetone extracts of dill leaves were investigated. In order to evaluate antioxidant activities of all extracts, different antioxidant tests were used, such as total antioxidant activity by ferric thiocyanate method, reducing power, DPPH (1,1-diphenyl-2-picryl-hydrazyl) free radical scavenging, hydrogen peroxide scavenging, and ferrous ions chelating activities. The content of phenolic compounds was also determined to be the gallic acid equivalent. Among the three extracts, the water extract of dill leaf showed the most potent antioxidative capacity in each assay, showing 79.66% (at 1 mg/mL) in the DPPH? radical scavenging activity, 63% (at 800 μg/mL) in the metal chelating effect, 60% (at 400 μg/mL) in the H2O2 scavenging activity, and 0.61 absorbance (at 1 mg/mL) in the reducing power.  相似文献   

9.
The antioxidant and antiproliferative properties of flesh and peel of mango (Mangifera indica L.) were investigated. The cytoprotective effect of mango flesh and peel extracts on oxidative damage induced by H2O2 in a human hepatoma cell line, HepG2, were determined, and the underlying mechanism was examined by a single-cell electrophoresis assay (comet assay). Treatment of HepG2 cell with mango peel extract prior to oxidative stress was found to inhibit DNA damage. The free radical scavenging activities of mango flesh and peel extracts were evaluated by electron spin resonance (ESR). The mango peel extract exhibited stronger free radical scavenging ability on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and alkyl radicals than mango flesh extract, regardless of ripeness. Similarly, peel extract exhibited significant antiproliferative effect against all tested cancer cell lines, compared to that of flesh extract, in a dose-dependent manner. The result also showed that the antiproliferative activity of mango flesh and peel extracts correlated with their phenolic and flavonoid contents. Thus, mango peel, a major by-product obtained during the processing of mango product, exhibited good antioxidant activity and may serve as a potential source of phenolics with anticancer activity.  相似文献   

10.
Free‐radical scavenging capacities of strawberries and blackberries treated with methyl jasmonate (MJ), allyl isothiocyanate (AITC), essential oil of Melaleuca alternifolia (tea‐tree oil or TTO), and ethanol (EtOH) were investigated. All of these natural volatiles tested reduced the severity of decay in both strawberries and blackberries during storage at 10 °C as compared to the control. Most of these compounds enhanced antioxidant capacity and free‐radical scavenging capacity, except the AITC treatment. The MJ treatment for strawberries and blackberries had the highest antioxidant capacity, expressed as oxygen radical absorbance capacity (ORAC) values, after 7 days of storage. Moreover, the MJ treatment promoted the antioxidant capacity in strawberries and blackberries as measured by the radical 2,2‐di (4‐tert‐octylphenyl) ‐1‐picrylhydrazyl (DPPH) and the radical cation 2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid) diammonium salt (ABTS?+) scavenging activity in both 7 and 14 days after storage. The MJ treatment also increased scavenging capacities on the superoxide radical (O2??), hydrogen peroxide (H2O2), hydroxyl radical (?OH), and singlet oxygen (1O2) in strawberries and blackberries. Treatment with TTO or EtOH enhanced most of these free‐radical scavenging capacities, except for H2O2 in strawberries, and for O2?? and 1O2 in blackberries. These results indicated that all of the natural volatile compounds tested in this study, except AITC, promoted the antioxidant capacity and scavenging capacity of most major free radicals and, thus, helped to improve the physiology of berry fruits and enhanced their resistance to decay. While AITC was also very effective in reducing decay, its effect on free‐radical scavenging capacity was inconsistent, suggesting that additional mechanisms may be involved in its inhibition of fungal growth. Copyright © 2007 Society of Chemical Industry  相似文献   

11.
The in vitro antimicrobial and antioxidant activities of the essential oil and methanolic extract of Micromeria fruticosa ssp serpyllifolia as well as the composition of the essential oil were examined. The essential oil exhibited activity against 14 bacteria, three fungi and a yeast, with minimal inhibitory concentration (MIC) values ranging from 31.25 to 125 µl ml?1, whilst the methanolic extract was inactive. Antioxidant activity was measured by two methods, namely scavenging of the free radical DPPH and inhibition of linoleic acid oxidation. The methanolic extract exhibited significant antioxidant activity in both assays, providing 50% inhibition at 70.9 ± 0.5 µg ml?1 concentration in the DPPH assay and inhibiting linoleic acid oxidation to 59% at 2 mg ml?1 concentration, whilst the essential oil showed activity only at higher concentrations. The gallic acid equivalent total phenolic content of the methanolic extract was found to be 55.2 ± 2.00 µg mg?1 dry weight extract (5.5% w/w). The chemical composition of the hydrodistilled essential oil was analysed by means of GC/MS. Twenty‐nine constituents were identified, the main ones being piperitenone (50.61%) and pulegone (29.19%). Copyright © 2004 Society of Chemical Industry  相似文献   

12.
Abstract: Six different cultivars of banana flowers (Musa paradicicus) (Kathali, Bichi, Shingapuri, Kacha, Champa, and Kalabou) were analyzed for the content of polyphenol expressed as gallic acid equivalent and flavonoid expressed as quercetein equivalent, and the in vitro total antioxidative activities of the flower extracts were compared with standard and expressed as trolox equivalent. The reducing power, 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and 2,2‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid) radical cation (ABTS?+) scavenging activities, inhibition of lipid peroxidation in a linoleic acid emulsion system, and liposome peroxidation system were measured and compared with respective standard antioxidants. Iron‐mediated Fenton reaction was carried out to evaluate the protective effect of the extract of banana flower (Kacha cultivar) against H2O2‐induced DNA damage. The Kacha variety contains the maximum amount of polyphenol (11.94 ± 0.03 mg of gallic acid equivalent/g of dry weight) and flavonoid (0.174 ± 0.001 g of quercetin equivalent/g of polyphenol). It also has the highest total antioxidant capacity, DPPH radical scavenging activity, and ABTS?+ radical scavenging activity with a least EC50 value of 0.051 mg/mL. Hepatic cell damage in iron‐mediated Fenton reaction caused by free radicals is reduced by the banana flower extract. On the basis of the results obtained, the banana flowers are found to be a potential source of natural antioxidants. This is the first report on the antioxidant properties of the extracts from banana flowers. The study suggests that the flowers of M. paradicicus that are found in India and consumed as vegetable can provide valuable functional ingredients that help in the prevention of oxidative stress.  相似文献   

13.
Nyctanthes arbor-tristis (Harsingar) leaf extracts are extensively used in Indian traditional medicine. The acetone-soluble fraction of its ethyl acetate extract showed impressive antioxidant activity as revealed by several in vitro experiments, e.g., DPPH, hydroxyl and superoxide radicals, as well as H2O2 scavenging assays. Moreover, its preventive capacity against Fe(II)-induced lipid peroxidation of liposomes and γ-ray-induced DNA damage also confirmed this. The strong reducing power and high phenolics and flavonoids contents could be responsible for the antioxidant activity.  相似文献   

14.
The antioxidant activity of phenolic extracts from olives and olive oil has been assessed by scavenging of 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radicals and by studying the effects on the stability of stripped olive oil in the absence and presence of ferric chloride. The olive extracts contained a much higher concentration (1940–5800 mg kg?1) of phenolic components than the olive oil extract (180 mg kg?1). Some olive extracts were more effective than the olive oil extract in scavenging DPPH radicals, but the three varieties of olives examined showed relatively large differences in both polyphenol concentration and antioxidant activity of extracts. α‐Tocopherol and extracts from both olives and olive oil were effective antioxidants in stripped olive oil at 60 °C. Ferric chloride reduced the stability of stripped olive oil, but the olive extract studied was significantly more effective as an antioxidant in the presence of the metal salt than the olive oil extract or α‐tocopherol. Ferric ions catalysed the oxidation of caffeic acid, oleuropein and phenolic components of the olive and olive oil extracts in aqueous solution (pH 5.4). The olive extract oxidised more rapidly than the olive oil extract in aqueous solution. © 2001 Society of Chemical Industry  相似文献   

15.
《Food chemistry》2005,90(3):333-340
This study was designed to examine the in vitro antimicrobial and antioxidant activities of the essential oil and various extracts (prepared by using solvents of varying polarity) of Salvia tomentosa (Miller). The essential oil was particularly found to possess strong antimicrobial activity while other non-polar extracts and subfractions showed moderate activities while polar extracts remained almost inactive. GC and GC/MS analyses of the oil resulted in the identification of 44 compounds, representing 97.7% of the oil; β-pinene (39.7%), α-pinene (10.9%) and camphor (9.7%) were the main components. The samples were also subjected to screening for their possible antioxidant activity by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and β-carotene-linoleic acid assays. In the first case, the free radical scavenging activity of aqueous methanol extract (MW) was superior to all other extracts (IC50=18.7 μg/ml). Polar extracts exhibited stronger activities than non-polar extracts. In the case of the linoleic acid system, oxidation of the linoleic acid was effectively inhibited by the polar subfraction of the MW extract, while the oil was less effective. The MW extract showed 90.6% inhibition, that is close to the synthetic antioxidant BHT.  相似文献   

16.
The crude methanol extract (ME) from camellia oil was fractionated by serial benzene, ether, EtOAc and n-BuOH, divided into five subfractions designated as SF1–5. The obtained fractions as well as ME were evaluated for their antioxidant activities using DPPH assay, and their phenolic constituents were isolated using silica gel column chromatography and analysed by TLC, RP-HPLC–PDA, UPLC-ESI–MS and GC–MS. Results showed that the content of total phenolics (TPs) of ME, determined by the Folin–Ciocalteu method, was estimated to be 79.5?±?10.2?mg of p-hydroxybenzoic acid equivalent/kg oil, while that of the total flavonoids was 8.98?±?0.54?mg of rutin equivalent/kg oil. ME exhibited pronounced radical-scavenging activity against the stable DPPH radical (with an antioxidant capacity IC50 value of 52.37?μg/mL), and three subfractions (SF1–3) separated from ME contributed the most significant activity with IC50 of 28.41, 17.42 and 43.17?μg/mL, respectively. Consistent with the different capacity of scavenging DPPH radicals, the subfractions from ME showed different composition and contents of phenolic compounds as detected by TLC, RP-HPLC–PDA, UPLC-ESI–MS and GC–MS. Kaempferol, as well as a number of volatile phenolic compounds, was first identified from camellia oil. Results showed that the presence of phenolic compounds and flavonoids in each extracts may be responsible for its individual antioxidant activity, and the lipophilic phenolic fractions would likely account for a great part of the antioxidant properties of the oil.  相似文献   

17.
The amount of phenolics, flavonoids, and anthocyanins in ethanol extracts and antioxidant activity of both ethanol and lipophilic extracts of common fruity vegetables in Bangladesh were studied. Among the ethanol extracts of 15 fruity vegetables, M. oleifera had the highest total polyphenol content (85.05 mg gallic acid equivalent/g extract) followed by L. acutangula (61.74 mg gallic acid equivalent/g extract) and A. esculentus (48.92 mg gallic acid equivalent/g extract). L. acutangula had high a content of flavonoids (14.46 mg (+)-catechin equivalent/g extract), which was almost similar to L. siceraria (13.67 mg catechin equivalent/g extract) followed by A. esculentus (11.95 mg catechin equivalent/g extract) and S. melongena (11.42 mg catechin equivalent/g extract). Highest anthocyanins content was in F. hispida (2.22 μmol/g extract) followed by S. melongena (1.04 μmol/g extract). Ethanol extracts of A. esculentus, F. hispida, L. acutangula, L. siceraria, and S. melongena exhibited high DPPH free radical scavenging activity with IC50 of 70.4, 64.9, 70.4, 64.9, and 94.3 μg/mL respectively, whereas for the same lipophilic extracts of F. hispida and S. melongena showed lowest (37 μg/mL) IC50 followed by M. oleifera (47.6 μg/mL), L. siceraria (57.5 μg/mL), and A. esculentus (63.3 μg/mL). These vegetables also showed high reducing powers, NO scavenging and total antioxidant capacity. Therefore, the top five potential fruity vegetables consist of both hydrophilic and lipophilic antioxidant(s), the order being F. hispida > M. oleifera > A. esculentus, L. acutangula > L. siceraria > and S. melongena.  相似文献   

18.
本文研究了生姜和醋泡姜的姜油和姜乙醇提取物的抗氧化、抑菌和抗肿瘤作用的活性差异。以抗坏血酸为对照,评价两类姜提取物的抗氧化活性(DPPH自由基、ABTS+自由基、羟自由基(·OH)清除能力和总还原能力);以96孔板微量稀释法比较了两类姜提取物对几种常见致病菌的抑菌活性;同时研究了两类姜提取物对HCT116(人结肠癌细胞)、HepG2(人肝癌细胞)、Skov3(卵巢癌细胞)等肿瘤细胞的抗癌效果。结果表明:醋泡姜的抗氧化活性总体上好于生姜,其中醋姜油对羟自由基(·OH)的清除能力(IC50为0.28 mg/mL)明显强于生姜油(IC50为0.42 mg/mL);生姜和醋泡生姜提取物都有一定的抑菌作用,醋姜油的抑菌效果稍好于生姜油,其中最好的是醋姜油对金黄色葡萄球菌的抑制作用(156.25 μg/mL);抗肿瘤活性基本相当。本研究结果表明,醋泡姜在抗氧化、抑菌功能上一定程度优于生姜。  相似文献   

19.
Methanol extracts of 4 different colored (red, orange, yellow, and green) bell peppers (Capsicum annuum L.) were examined to (1) determine the total phenolic content (TPC), (2) compare the antioxidant activities, (3) assess the protective effects of extracts on H2O2-induced and 4-hydroxy-2-nonenal (HNE)-induced DNA damage using the Comet assay, and (4) examine the antiproliferative action of their extracts on HT-29 cells. Red and orange bell peppers had significantly higher levels of TPC than yellow or green bell peppers. Orange bell pepper exhibited the highest level of radical scavenging activity and total antioxidant activity, while green bell pepper exhibited the highest superoxide dismutase-like activity. These results suggest that the difference in antioxidant activities may depend on the kinds of antioxidant compounds related to the color of the pepper. It was found a significant negative correlation between TPC and radical scavenging activity inhibiting capacity (IC)50, and a significant positive corretation between TPC and total antioxidant activity. All extracts of bell pepper inhibited H2O2-induced and 4-hydroxy-2-nonenal-induced DNA damage in human leukocytes and showed potential toxicity on HT-29 cells. These findings suggest that the 4 different colored bell peppers may be useful as antioxidants and cancer prevention in food.  相似文献   

20.
The quenching capacities of Vitus vinifera seed extract, Citrus limon peel extract, Punica granatum peel extract, and Citrus sinensis peel extract were studied together with their antioxidant activity in goat fish (Parupenaeus indicus). The functionality of the extracts was evaluated using β-carotene-linoleic acid model system, reducing power assay, DPPH, hydroxyl, and nitrite radical scavenging assay. V. vinifera and P. granatum extract demonstrated best radical scavenging potential in all multifunctional antioxidant assays. Radical scavenging activity measured by electron paramagnetic resonance against a stable radical 1,1,-diphenyl-2-picrylhydrazil revealed radical peaks of lower intensity in antioxidant-infused samples. Compounds possessing antioxidant properties were identified from purified fruit extracts by GC–MS analysis. Treatments with these extracts increased the stability of irradiated goat fish against lipid oxidation. TBARS values for irradiated control was 4.26 ± 0.10, whereas it was 2.44 ± 0.14, 2.97 ± 0.01, 2.93 ± 0.03, 3.89 ± 0.05, and 4 ± 0.01 mg of MDS per kilogram fish for BHA, P. granatum peel, V. vinifera seed, C. sinensis peel, and C. limon peel extract-treated samples, respectively. This study also elucidated the relationship between heating temperature and irradiation dose on the antioxidant activity of extracts. Maximum antioxidant activity was observed at 150 °C heated and 10-kGy irradiated extracts. These results suggest that fruit peels will be a potential material for extracting antioxidants.  相似文献   

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