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1.
Antioxidants are compounds responsible for free radical scavenging in the body. They protect the organism from oxidative modification of cells and tissues. These modifications have been associated with degenerative diseases, atherosclerosis and carcinogenesis. Punica granatum displays high antioxidant potential due to the presence of phenolic compounds, which are capable of disease prevention. The present study showed the highest antioxidant activity in pomegranate peel than in seeds and pulp. Based on these results, pomegranate peel was used to produce dried extract that was added to commercial tomato juice and orange juice with strawberries. Analysis to determine the content of phenolic compounds and antioxidant activity was performed on pomegranate pulp, seeds and peel and in juices enriched with dried extract of pomegranate peel. The dried extract was responsible for a significant increase in antioxidant activity of the juices, proportional to the concentrations added. However, although both flavors of enriched juices displayed high antioxidant levels, the samples with higher dried extract concentrations received the lowest scores from sensory analysis participants due to the characteristic astringent flavor of pomegranate peels. Therefore, to obtain greater acceptance in the consumer market, we concluded that the maximum addition of dried pomegranate peel extract is 0.5% in tomato juice and orange juice with strawberries.  相似文献   

2.
This study compares the antioxidant activity of ten different pomegranate cultivars grown in Iran using the ferric reducing power assay (FRAP assay), which is based on the reduction of a ferric-tripyridyl triazine complex to its ferrous, colored form in the presence of antioxidants. Aqueous solutions of known Fe(+2) concentration, in the range of 100-1000 micromol L(-1) were used for calibration. The results showed that among pulp and peel fractions the sour alac and sweet white peel cultivars had more FRAP value respectively. The pomegranate peel extract had markedly higher antioxidant capacity than the pulp extract. The peel extract of sweet white peel cultivar appeared to have more potential as a health supplement rich in natural antioxidants compared to the pulp and peel extracts of other pomegranate cultivars.  相似文献   

3.
The methanolic extract of Cassia hirsuta L. seed materials, an underutilized food legume collected from India, was analyzed for antioxidant activity and health relevant functionality. The methanolic extract of raw seeds contained a total free phenolic content of 15.82?±?1.69 g catechin equivalent/100 g extract DM. Encouraging levels of ferric reducing/antioxidant power (FRAP, 1,446 mmol Fe[II]/mg extract), inhibition of ß-carotene degradation (48.81%) and scavenging activity against DPPH (64.40%) and superoxide (43.78%) radicals were exhibited by the raw samples. Further, 83.11% of α-amylase and 62.79% of α-glucosidase enzyme inhibition characteristics under in vitro starch digestion bioassay were also recorded. Sprouting + oil-frying caused an apparent increase on the total free phenolic content and a significant improvement in the antioxidant and free radical scavenging capacity of methanolic extract of C. hirsuta seeds, while soaking + cooking as well as open-pan roasting treatments showed diminishing effects. The analysis of the phenolic profile revealed the presence of gallic acid, p-coumaric acid and (+)-catechin in the methanolic extract of these seeds.  相似文献   

4.
The present work is designed to evaluate the bioactive properties of the crude methanolic extract of Jatropha curcas oil and its solvent fractions. The crude methanolic extract obtained was fractionated using a hydrophilic lipophilic balanced (HLB) cartridge and then eluted with different solvents in the order of hexane (F1), dichloromethane (F2), chloroform (F3), ethyl acetate (F4) and methanol (F5), respectively. Total phenolic content of the crude methanolic extract and its fractions was in the range of 0.19-4.5 mg/g as gallic acid equivalent. Antioxidant activity of the crude methanolic extract and its fractions were determined by two complementary test methods, namely, phenanthroline method and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging method. All samples demonstrated weak antioxidant activity (150-851 μmol Fe/100 g of the extract and IC50 of 1.05-13.5 mg/mL). When compared to butylated hydroxytoluene (BHT), a reference synthetic antioxidant, both showed weaker antioxidative potential. The evaluation of antimicrobial activity of the extracts was performed using a disc diffusion method and a micro-well dilution method against six economic plant disease bacteria. The results showed that all extracts possessed strong to moderate antibacterial activity with varying degrees of growth inhibition against the test bacteria. The minimum inhibitory concentrations (MIC) were in the range of 14.92-428.6 μg/mL. In addition, the chemical constituents in each fraction of the extract were subjected to analyze by gas chromatography-mass spectrometry (GC-MS). The eleven constituents were identified. Among them, 2,4-di-tert-butylphenol, methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate and linoleic acid may be the main cause of its strong antibacterial activity. Therefore, this oil present in the methanolic extract had great potential as effective antibacterial sources.  相似文献   

5.
Common beans are rich in phenolic compounds, which can provide health benefits to the consumer. The objective of this work was to study the relationship among antimutagenicity, antioxidant and enzymatic activities of methanolic extract and trolox by principal components multivariate analysis. Antimutagenicity of phenolic compounds present in methanolic extract from the seed coat of common beans (P. vulgaris, Flor de Mayo Bajío cultivar) and trolox against AFB1 mutagenicity were evaluated in the Salmonella typhimurium microsuspension assay. Antioxidant capacity of methanolic extract and trolox were evaluated using β-carotene and 1,1-diphenyl-2-picryhydrazyl (DPPH) in vitro model assays. Cythrome P450 activity was measured by fluorometric assay. For phenolic extract, trolox and phenolic extract + trolox, the inhibition on AFB1 mutagenicity in tester strain TA100 was 47, 59 and 69%, respectively. While in TA98 was 39, 48 and 68%. The inhibition of phenolic compounds, trolox and phenolic compounds + trolox on cytochrome P450 (CYP450) activity was 48, 59 and 88%, respectively. Correlation analysis showed that phenolic extract and trolox have high antimutagenic and antioxidant activity and also inhibited enzymatic activity. The results suggest that the primary mechanism of action of phenolic compounds in beans against AFB1 mutagenicity may be extra-cellular in the microsuspension assay.  相似文献   

6.
The scavenging activity against DPPH (1,1-diphenil-2-picrylhydrazyl) radical and the antifungal effect against chloroform, ethyl acetate and 50% methanolic extracts of Verbena officinalis leaves were investigated. The activity of different fractions of 50% methanolic extract and some isolated compounds were also investigated. The results suggest that 50% methanolic extract and caffeoyl derivatives could potentially be considered as excellent and readily available sources of natural antifungal and antioxidant compounds.  相似文献   

7.
Epidemiological studies support the belief that whole grains are protective against several chronic diseases. The health benefits of whole grains are attributed in part to their unique phytochemical composition. Major phytochemicals in grains include various classes of phenolic compounds, flavonoids and coumarin derivatives, etc. Phenolic compounds present in grains possess antioxidant properties that are associated with the health benefits of grains and grain products. Sorghum is one of the main staple cereal grains in hot dry tropics and ranks fifth among cereal crops in the world. Although sorghum is rich in phenolics and tannins which are proven anticancer and cardioprotective constituents, human consumption of sorghum is limited. To our knowledge, there is limited literature on the profile of antioxidant phytochemicals in the local white variety of sorghum. Hence, the objective of this study was to investigate the antioxidant property of white sorghum flour extracts in vitro and also to identify the fractions responsible for the antioxidant activity. In the present study, we analyzed the antioxidative properties of various extracts (water, 60% methanol, 60% ethanol, and 60% t-butanol) of white sorghum flour employing the 1,1-diphenyl-2-picrylhydrazyl (DPPH) model system. Phenolics, antiradical and antioxidant activities were also examined in chromatographic sub-fractions of the soxhlet methanolic extract. Our results indicated that the various extracts exhibited significant antioxidant activity that did not correlate with the phenolic content. Further, two sub-fractions eluted with methanol and acetone/methanol were found to possess strong antioxidant activity in two assay systems. Our results suggest that a diet rich in sorghum may be useful in combating diseases in which free radical production plays a key role.  相似文献   

8.
Tea fruit peel is the main byproduct during manufacture of tea seed oil. The great increase in tea seed oil production in recent years brings the challenge of finding application for tea fruit peel. The aims of this study were to obtain tea fruit peel extracts enriched with bioactive compounds by several solvent extraction methods and to evaluate their antioxidant activity and inhibitory potential against α-glucosidase and α-amylase in vitro. Flavonoids and phenolics were accumulated in ethyl acetate, butanol, and chloroform fractions, and these fractions possessed much better antioxidant activities, including scavenging effect on 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH) and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) cation radicals (ABTS+), and reducing activity, compared with those of the 75% ethanol extract and water fraction. Moreover, the ethyl acetate, butanol, and chloroform fractions exhibited excellent inhibitory activity against α-glucosidase, much stronger than that of the positive control (acarbose). These fractions also showed mild inhibition on α-amylase activity.  相似文献   

9.
The antifungal activity of acetone, methanol, hexane and dichloromethane leaf extracts of six plant species (Bucida buceras, Breonadia salicina, Harpephyllum caffrum, Olinia ventosa, Vangueria infausta and Xylotheca kraussiana) were evaluated for antifungal activity against seven plant pathogenic fungal species (Aspergillus niger, Aspergillus parasiticus, Colletotricum gloeosporioides, Penicillium janthinellum, Penicillium expansum, Trichoderma harzianum and Fusarium oxysporum). These plant species were selected from 600 evaluated inter alia, against two animal fungal pathogens. All plant extracts were active against the selected plant pathogenic fungi. Of the six plant species, B. buceras had the best antifungal activity against four of the fungi, with minimum inhibitory concentration (MIC) values as low as 0.02 mg/ml and 0.08 mg/ml against P. expansum, P. janthinellum, T. harzianum and F. oxysporum. Some of the plant extracts had moderate to low activity against other fungi, indicating that the activity is not based on a general metabolic toxicity. P. janthinellum, T. harzianum and F. oxysporum were the most sensitive fungal species, with a mean MIC of 0.28 mg/ml, while the remaining four fungi were more resistant to the extracts tested, with mean MICs above 1 mg/ml. The number of active compounds in the plant extracts was determined using bioautography with the listed plant pathogens. No active compounds were observed in some plant extracts with good antifungal activity as a mixture against the fungal plant pathogens, indicating possible synergism between the separated metabolites, B. salicina and O. ventosa were the most promising plant species, with at least three antifungal compounds. Leaf extracts of different plant species using different methods (acetone, hexane, DCM and methanol) had antifungal compounds with the same Rf values. The same compounds may be responsible for activity in extracts of different plant species. Based on the antifungal activity, crude plant extracts may be a cost effective way of protecting crops against fungal pathogens. Because plant extracts contain several antifungal compounds, the development of resistant pathogens may be delayed.  相似文献   

10.
The use of plant-derived products in postharvest disease management may be a valid alternative to conventional chemical treatments. In this study, the antifungal activity of crude foliar extracts of a wild Capsicum annuum accession against Alternaria alternata was assessed. Pepper extracts affected mycelial growth and suppressed conidia germination in a dose-dependent manner. Moreover, they significantly reduced soft rot disease severity on artificially infected ripe cherry tomatoes. Extracts were characterized for their total phenolic content and antioxidant activity. UPLC–DAD analysis was also performed to obtain phenolic profiles of extracts and quantify the individual known components, including gallic acid, chlorogenic acid, catechin, caffeic acid, p-coumaric acid and ferulic acid. The putative role of this class of molecules in conferring antifungal activity to the extracts is discussed. The results indicate that extracts rich in natural phenolic compounds could be promising for sustainable applications in crop protection.  相似文献   

11.
研究不同浓度玉米秸秆浸提液对玉米、大豆和小麦3种作物种子萌发及其幼苗叶片抗氧化物酶活性、丙二醛含量、脯氨酸含量以及根活性等指标的影响。结果表明,玉米秸秆浸提液促进玉米和小麦种子萌发,发芽率分别提高18.4%和7.6%;秸秆浸提液浓度为0.8 g/m L时,对大豆种子萌发有显著抑制作用,发芽率降低11.3%。不同浓度秸秆浸提液处理,3种作物根系活力、抗氧化物酶活性和丙二醛、脯氨酸含量受到不同程度抑制或促进作用,无明显规律。  相似文献   

12.
In the present study, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase inhibitory and antioxidant activities of the fruit and leaf extracts of Melia azedarach L. (Meliaceae) of Turkish origin were evaluated. Enzyme inhibitory activity of the extracts was tested in vitro using ELISA microplate reader. Antioxidant activity of the extracts was tested using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferrous ion-chelation, and ferric-reducing antioxidant power (FRAP) assays. Phenolic composition of the extracts was elucidated by high performance liquid chromatography (HPLC) and fatty acid compositions of the fatty oils of the fruits and leaves were elucidated by gas chromatography-mass spectrometry (GC-MS). The ethyl acetate extract from the leaves showed the highest inhibition against AChE (33.63 ± 1.40%) and BChE (92.89 ± 3.05%). The methanol extract from the leaves exerted the best antioxidant activity in DPPH radical scavenging and FRAP assays, while the ethyl acetate extracts of the fruits and leaves had the most notable effect in metal-chelation assay.  相似文献   

13.
The purpose of this study was to evaluate the hypolipidemic effect of a methanolic extract from Opuntia joconostle seeds fed to mice in a hypercholesterolemic diet. Acute toxicity of the methanolic extract was investigated by an established method. Phenolic composition and antioxidant activity were determined by high-performance liquid chromatography and DPPH, respectively. The total phenolic content of Opuntia joconostle seeds was 47.85?±?1.29 mg gallic acid equivalents/g dry weight. The main phenolic compounds were identified as quercetin, rutin, and cafeic acid. Percent inhibition of DPPH+ was 49.76?±?0.49 %. The oral LD50 for the methanolic extract from the Opuntia joconostle seeds was >5,000 mg/kg BW. Mice fed a hypercholesterolemic diet for six days exhibited significantly (P?≤?0.001) higher plasma lipid levels than mice fed a normal diet. Remarkably, supplementation with methanolic extract from Opuntia joconostle at doses of 1, 2, and 5 g/kg body weight significantly (P?≤?0.001) prevented the increase in total cholesterol, low-density lipoprotein cholesterol, triglycerides level, and atherogenic index. Similar concentrations of the HDL cholesterol were observed in both treated and control groups. A significant dose-dependent reduction in lipid levels was noted for treated groups compared to the hypercholesterolemic group. We attribute this result to the seeds’ phenolic composition. This methanolic extract has potential to be included in short-term hypercholesterolemia treatment regimens as it exhibits hypolipidemic activity with no apparent toxic manifestations.  相似文献   

14.
Water and methanol extracts from roots of Ozoroa paniculosa (Anarcardiaceae); seeds of Colophospermum mopane (Caesalpiniaceae) and Cucumis metuliferus (Cucurbitaceae) ripe fruits were assessed for in vitro antioxidant activity. Free radical scavenging activity was measured spectrophotometrically as maximum fading power of DPPH at 525 nm. Water and methanol extracts of Ozoroa paniculosa exhibited higher scavenging potency than extracts of either Colophospermum mopane or Cucumis metuliferus at all tested concentrations. None of the extracts from Cucumis metuliferus exhibited any recognizable free radical scavenging activity. Above 50 microg mL(-1) both water and methanol extracts of Ozoroa paniculosa exhibited 91% scavenging activity similar to the control compounds L-ascorbic acid (91%) and (-) epicatechin (92%). Between 50-100 microg mL(-1), water and methanol extracts of Colophospermum mopane exhibited scavenging potency of < or = 70%. However, above 100 microg mL(-1), both water and methanolic extracts of C. mopane exhibited scavenging activity > 70%. Chloroform extracts of all the tested plants showed poor scavenging activity (< 30%). The order of scavenging potency for the tested samples was as follows: L-ascorbic acid > or = epicatechin > O. paniculosa (methanolic extract) > O. paniculosa (water extract) > O. paniculosa (ethylacetate extract) > C. mopane (methanolic extract) > C. mopane (water extract) > all extracts of C. metuliferus. These findings lend credence to the use of these plants as anti-inflammatory and antioxidant agents in folk medicine.  相似文献   

15.
Carotenoids and phenolic profile, antioxidant activity as well as concentrations of selected macronutrients (K, N, Mg, Ca and Na) and micronutrients (Zn, Cu and Mn) in flesh and peel of peach fruit were recorded at two harvest dates. Predominant mineral was potassium, followed by calcium, magnesium and sodium. The concentration of most micronutrients was greater in the peel than in the flesh especially in early season. The concentration of most elements in flesh and peel decreased during fruit maturation. Total carotenoids content varied with respect to the cultivar. β-cryptoxanthin and β-carotene were the major carotenoids in both tissues and flesh contain the lowest amounts. Neochlorogenic acid, chlorogenic acid, catechin, epicatechin, gallic acid, rutin, quercetin-3-O-galactoside, cyanidin-3-O-glucoside, cyanidin-3-O-rutinoside, were detected in both peel and flesh, with chlorogenic acid and catechin being the predominant components. Peel extracts showed markedly higher antioxidant activities, when estimated by ABTS or DPPH assays, than the flesh counterparts, consistent with the observed higher phenolic content. Overall, total phenolics levels increased at full ripening stage in both peel and flesh. The results found herein provide important data on carotenoids, phenolic and macro- and micronutrient changes during fruit growth, and emphases peach fruit as a potential functional food.  相似文献   

16.
对杧果皮乙醇提取的乙酸乙酯萃取物进行抑菌性测定。离体抑菌活性测定结果表明,乙酸乙酯萃取物对小麦纹枯和水稻纹枯等病原菌具有很强的抑菌活性;硅胶柱层析及生物活性测定结果表明,正己烷∶乙酸乙酯∶无水甲醇为 60∶40∶20(v∶v∶v)时对抑菌成分的分离效果最好;化学定性分析结果表明,对水稻纹枯病菌抑菌最强的(11~13)组段的化学成分主要为酚类、黄酮类和有机酸等物质,但具体是那一类物质起作用还需要进一步分离纯化和鉴定。  相似文献   

17.
The antifungal activity of the methanolic extract ofMahonia napaulensis D.C. or Taming (local name) leaves was evaluated with four species of common pathogenic fungi e.g.Colletotrichum capsici (MTCC No. 2071),Leptosphaerulin trifoli (MTCC No. 2328),Alternaria brassicicola (MTCC No. 2102) andHelminthosporium solani (MTCC No. 2075). The present investigation also aims at developing an eco friendly natural antifungal finish from plant extract ofMahonia for textile application. The antifungal textile dyeing was also carried out with aqueous extract of stem and leaves ofMahonia and the dyed fabric was tested against fungal speciesTrichoderma for its antifungal activity in vitro.Mahonia extract showed substantial antifungal activity of 83.33% forLeptosphaerulin trifoli andAlternaria brassicicola by 80 ppm dose in 24 hours and 46% antifungal activity inMahonia dyed pieces in broth againstTrichoderma.  相似文献   

18.
Pseudomonas syringae pv. tomato, the causal agent of tomato bacterial speck, is common in greenhouses and fields all over Italy. The antibacterial activity of ethanol extracts of Punica granatum (pomegranate) fruit peels on P. syringae pv. tomato was studied both in vitro and in vivo. The minimum in vitro inhibition value for peel extract of P. granatum on the P. syringae pv. tomato Pt 1301 strain (from Turkey) was obtained at a concentration of 0.5%. The in vivo antibacterial action of this natural substance lasted at least 15 days, permitting the replacement or reduction of the commonly used copper compounds. The active components of the pomegranate peel extracts were ellagic and gallic acids.  相似文献   

19.
Avocado seed contains elevated levels of phenolic compounds and exhibits antioxidant properties. We investigated the effect of Avocado Seed Flour (ASF) on the lipid levels in mice on a hyperlipidemic diet. The concentration of phenols was determined by high-performance liquid chromatography, antioxidant activity was evaluated using the Trolox equivalent antioxidant capacity method, and dietary fiber was measured using the Association of Official Analytical Chemists (AOAC) method. The LD50 of ASF was determined using Lorke’s method and hypolipidemic activity was evaluated in a hypercholesterolemic model in mice. Protocatechuic acid was the main phenolic compound found in ASF, followed by kaempferide and vanillic acid. The total phenolic content in the methanolic extract of ASF was 292.00 ± 9.81 mg gallic acid equivalents/g seed dry weight and the antioxidant activity resulted in 173.3 μmol Trolox equivalents/g DW. In addition, a high content of dietary fiber was found (34.8%). The oral LD50 for ASF was 1767 mg/kg body weight, and treatment with ASF significantly reduced the levels of total cholesterol, LDL-C, and prediction of the atherogenic index. Therefore, the antioxidant activity of phenolic compounds and dietary fiber in ASF may be responsible for the hypocholesterolemic activity of ASF in a hyperlipidemic model of mice.  相似文献   

20.
The chestnut bur, a forest waste product from chestnut processing in the food industry, was studied as a potential source of natural antioxidants. Extractions were performed using aqueous solutions of methanol or ethanol. Experiments were planned according to an incomplete 33 factorial design to study the influence of temperature (25-75 °C), time (30-120 min) and solvent concentration (50-90%) on extraction yield and on extract properties: total phenols content, antioxidant activity (using the FRAP, DPPH and ABTS methods) and average molecular weights. All dependent variables were influenced by temperature and solvent concentration whereas the influence of time was almost negligible. Using the response surface methodology the optimal extraction conditions were selected: the highest temperature assayed (75 °C), the lowest solvent concentration (50%) and an extraction time of 75 min for the methanolic extractions and of 30 min for the ethanolic ones. Under those conditions the values predicted for extraction yield and total phenols content were 18.95% and 36.32 g GAE/100 g extract for the methanolic extract and 17.95% and 26.11 g GAE/100 g extract for the ethanolic ones. Methanolic extracts showed superior total phenols content and antioxidant properties and slightly higher extraction yields than ethanolic extracts; however, ethanol is recommended for food applications due to its GRAS (Generally Recognized as Safe) qualification. Gallic acid esters of glucose, ellagic acid and small proportions of quercetin-3-β-d-glucoside, phenolic compounds with demonstrated antioxidant properties, were identified in chestnut bur extracts by RP-HPLC-ESI-TOF.  相似文献   

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