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1.
This study was designed to examine the in vitro antimicrobial and antioxidant activities and the amount of total phenolics of the methanol extracts of Ballota rotundifolia L. and Teucrium chamaedrys C. Koch. In the case of antimicrobial activity tests, polar sub-fractions of the methanol extracts of plant species exhibited weakest antimicrobial activity when compared with the non-polar ones. While, non-polar sub-fraction of B. rotundifolia showed moderate activity against A. lwoffii, C. perfringens and the yeasts, T. chamaedrys performed excellent activity pattern against all of the tested microorganisms. The sub-fractions were also screened for their possible antioxidant activities by two complementary tests, namely DPPH free radical-scavenging and β-carotene/linoleic acid assays. Non-polar extracts of the plant species remained inactive in both test systems. On the other hand polar extracts showed remarkable antioxidant activities. In DPPH system, free radical scavenging effect of T. chamaedrys was measured as 18.00 ± 1.42 μg.mg−1. It is extremely important to point out that, polar sub-fraction of T. chamaedrys is found as effective as the positive control BHT. Non-polar sub-fraction of T. chamaedrys found to have the highest total phenolic amount (97.12 ± 1.28 μg/mg). Results obtained from this experiment confirm the relationship between the amount of phenolics and biological activities.  相似文献   

2.
Eriobotrya plants are known to have significant amounts of phenolics and flavonoids, and exhibit a strong antioxidant activity. Experiments were conducted to examine variation in the contents of total phenolics and flavonoids, and antioxidant activities in the leaves of 11 Eriobotrya species (Tibet loquat, Daduhe loquat, Hengchun loquat, Taiwan loquat, Oak leaf loquat, Bengal loquat, Fragrant loquat, Guangxi loquat, Obovate loquat, Big flower loquat, and common loquat, the last species include two materials, one is a cultivar ‘Zaozhong 6’, another is a wild tree). In these species, ‘Zaozhong 6′ loquat is a cultivar. The leaf extracts of ‘Tibet’, ‘Obovate’, ‘Taiwan’, ‘Bengal’ and ‘Hengchun’ loquats exhibited significantly higher contents of total flavonoids and total phenolics, compared with those of other species. Of these 11 species, the highest contents of total phenolics and total flavonoids were observed in ‘Tibet’ and ‘Obovatae’ loquats, respectively. The significantly stronger antioxidant abilities assessed by the DPPH radical scavenging activity and reducing power were obtained in the leaf extracts of ‘Taiwan’, ‘Tibet’, ‘Bengal’, ‘Oak leaf’, ‘Hengchun’ and ‘Obovate’ loquats, compared with the other species. In addition, significant correlations were found between the contents of total phenolics or flavonoids and DPPH radical scavenging activity/reducing power. This work indicates that the leaf extracts of the wild Eriobotrya species, ‘Tibet’, ‘Obovatae’, ‘Taiwan’, ‘Bengal’, ‘Oak leaf’ and ‘Hengchun’ loquats, exhibited significantly higher levels of total phenolics and flavonoids, and significantly stronger antioxidant activities, compared with the cultivated species, ‘Zaozhong 6′ loquat, which suggests that these wild species have a better utilization value.  相似文献   

3.
The antioxidative activities of water extract (WE) and crude hot-water soluble polysaccharide (PS) from Ficus carica L. fruit were investigated using various assays in vitro, including scavenging abilities on DPPH, superoxide and hydroxyl radicals and reducing power. The immunity activities of PS were evaluated using the carbon clearance test and serum hemolysin analysis in mice. In addition, total phenolics and flavonoids contents were also determined. Both WE and PS have notable scavenging activities on DPPH with the EC50 values of 0.72 and 0.61 mg/ml, respectively. The PS showed higher scavenging activity than WE on superoxide radical (EC50, 0.95 mg/ml) and hydroxyl anion radical (scavenging rate 43.4% at concentration of 4 mg/ml). The PS (500 mg/kg) also has a significant increase in the clearance rate of carbon particles and serum hemolysin level of normal mice. The results indicate that both WE and PS might be applicable in healthy medicine and food industry.  相似文献   

4.
We report for the first time the antioxidant and antimutagenic activities of fractions from Randia echinocarpa fruit, which is a Rubiaceae plant native to Sinaloa, Mexico. This fruit has been traditionally used in the prevention or treatment of cancer, among other diseases. The pulp of the fruit was sequentially extracted with solvents of different polarity (i.e. hexane, chloroform, methanol and water). A high extraction yield was obtained with methanol (72.17% d.w.). The aqueous extract showed the highest content of phenolics (2.27 mg/g as ferulic acid equivalents) and the highest antioxidant activity based on the β-carotene bleaching method (486.15). The commercial antioxidant BHT was used as control (835.05). Antimutagenic activity of the aqueous extract (0–500 μg/tube) was evaluated using the Salmonella microsuspension assay (YG1024 strain) and 1-NP as the mutagen (50 and 100 ng/tube). The aqueous extract was neither toxic nor mutagenic and the percentage of inhibition on 1-NP mutagenicity was 32 and 53% at doses of 50 and 100 ng/tube, respectively. The results of the double incubation assay suggest that the extract inhibited the mutagenicity of 1-NP by a combination of desmutagenic and bioantimutagenic effects.  相似文献   

5.
Organic solvent (methanol, ethanol, and acetone) extracts and water extracts of cherry (Prunus serrulata var. spontanea) blossoms were prepared, and antioxidant activities of the extracts were evaluated. Methanolic CBE (100 μg/ml) showed the highest total phenol content (104.30 μM), radical scavenging activity (34.2%), and reducing power (0.391). The effect of CBE on DNA damage induced by H2O2 in human leukocytes was evaluated by Comet assay. All CBE was a potent dose dependent inhibitor of DNA damage induced by 200 μM of H2O2, methanolic CBE showed the most strong inhibition activity. The methanolic CBE of 500 μg/ml showed 38.8% inhibition against growth of human colon cancer cell line HT-29. These results indicated that cherry blossoms could provide valuable bioactive materials.  相似文献   

6.
The aqueous extracts of four marine algae, Caulerpa racemosa var. macrophysa, Gracilaria tenuistipitata var. tenuistipitata, Sargassum sp., and Ulva lactuca, from the coastal areas in Southern Thailand, were prepared by boiling dried seaweed powder in water for 3 h, and by autoclaving each sample at 120 °C for 3 h. They were then freeze-dried and evaluated for their antioxidant activities using DPPH (1, 1-diphenyl-2-picrylhydrazyl), hydroxyl radical (OH) and superoxide anion (O2•−) scavenging assays. Boiling extracts of the seaweeds, except C. racemosa, were found to have higher total phenolic contents (TPC) than those obtained from the autoclave method. The antioxidant results also showed that O2•− scavenging activity existed only in the boiling extracts of C. racemosa, G. tenuistipitata, and U. lactuca. In DPPH and OH assays, however, almost all the boiling extracts were less active than the autoclave ones. Among the four alga species, Sargassum sp. was the most active. Both extracts of this seaweed had the highest TPC and also displayed the strongest DPPH and OH inhibitory activities. A strong positive-correlation between the antioxidant potency and TPC of the autoclave extracts was found, while for the boiling extracts such relation was very weak. This result thus reflected that in addition to the phenolic compounds, there might be some other active components present in these extracts involved in the antioxidant activity.  相似文献   

7.
Bromelia pinguin L. is a plant native to Sinaloa, Mexico, where its fruit is used as food or as a phytotherapeutic agent. The fruits of B. pinguin were characterized and they could be considered as a functional food. These fruits show an average weight of 13.7 g and a yellow color of high luminosity (b* = 43.2, L* = 74.5). The values for acidity (4.6%, as citric acid) and pH (3.7) of B. pinguin fruit are similar to those of citrics. The edible portion is characterized by a high content of vitamin C (126 mg/100 g), ash (10.6 g/100 g d.w.), crude fiber (3.4 g/100 g d.w.), calcium (1290 mg/100 g d.w.), magnesium (500 mg/100 g d.w.), manganese (2.95 mg/100 g d.w.) and it is a good source of zinc (2.8 mg/100 g d.w.). Polar fractions extracted from the pulp fruit showed activity against several genera of human pathogenic-bacteria (Staphylococcus, Streptococcus, Enterococcus, Salmonella, Shigella, Escherichia and Pseudomonas).  相似文献   

8.
Total antioxidant activity of six non-cultivated but traditionally collected fruits from the south of Europe was assessed by measuring their ability to reduce the hydroxyl radical ( OH· ) \left( {{\hbox{O}}{{\hbox{H}}^\bullet }} \right) and hydrogen peroxide (H2O2), and their Trolox equivalent antioxidant capacity (TEAC). This antioxidant activity was compared with that shown by the synthetic antioxidants BHA (E-320), BHT (E-321) and propyl gallate (E-310). Total phenolics, ascorbic acid and the carotenoid content of the fruits were also analyzed. All fruits showed a high ability to scavenge the OH· {\hbox{O}}{{\hbox{H}}^\bullet } radical, ranging from 60.61% to 81.04% inhibition for Rosa canina and Crataegus monogyna, respectively. The H2O2 scavenging capacity and the TEAC value varied widely, ranging between 3.63% and 87.26% inhibition of H2O2 and between 0.47 and 416.64 mM trolox g−1 FW for Sorbus domestica and Rosa canina, respectively. The antioxidant activity of fruits was higher than that of the synthetic additives analyzed, except in the TEAC assay. The phenolic and carotenoid content of R. canina was much higher than that of the other fruits analyzed and its ascorbic acid concentration was also high, reflecting its higher efficacy towards ABTS ·- {\hbox{ABT}}{{\hbox{S}}^{ \bullet - }} (TEAC assay) and H2O2 species. In spite of these associations, the correlation coefficients between total antioxidant activity and the antioxidant compounds analyzed were not very significant; only phenolics and carotenoids showed a marginal correlation with the TEAC assay. The results support the possible use of R. canina as natural antioxidant to replace the synthetic additives, as well as their use in the production of functional foods with a high antioxidant activity.  相似文献   

9.
Antioxidant activity of pressurized low polarity water (PLPW) extracts of cow cockle seed and extraction residues were determined using DPPH, ABTS, and FRAP assays. The effect of extraction conditions (temperature (125, 150 and 175 °C) and time) on the antioxidant activity and the relationship amongst the antioxidant activity and extract composition (total phenolics and saponin content) were determined. The antioxidant activity of PLPW extracts increased with extraction temperature. Increasing activity with time was also observed at 175 °C. PLPW extraction residues had the highest activity suggesting antioxidant compounds were not completely extracted by PLPW. Antioxidant activity correlated well with total phenolics content of samples (R 2 ≥ 0.94), however no correlation was observed with the saponin content. A strong correlation was observed between the antioxidant activity values obtained using different methods (R 2 ≥ 0.94). These results point to the potential of PLPW extraction as a method to modify the activity of biological materials for the production of customized extracts.  相似文献   

10.
Crude ethanol extracts from different tissues of Betula alleghaniensis: wood, inner and outer bark, foliage, and twigs were evaluated for their nitric oxide (NO)-radical scavenging activities and inhibitory effects on the production of NO in LPS/INFγ-stimulated RAW 264.7 macrophages. As a renewed interest in plant-derived drugs has led to an increased need for efficient extraction methods, ultrasonic-assisted extraction (UAE) was investigated and compared with conventional maceration. The lower energy consumption by the UAE process compared to maceration determined in our study qualifies also this extraction as an environmentally friendly process. Our results indicate that the foliage extract has the most potent radical scavenging capacity while wood and twigs extracts exert the highest inhibitory effects on the production of NO in LPS/INFγ-stimulated RAW 264.7 macrophages. Extracts obtained by UAE present lower cytotoxic activity on RAW cells. Our results also demonstrate that ultrasounds help to selectively extract the bioactive molecules from foliage, twigs and wood, which inhibit the production of NO by macrophages. The highest total phenol content has been determined for the inner bark extracts and the flavonoids are the major phenolics present in foliage extracts. Poor correlations determined between the total phenols and radical scavenging capacity of the extracts indicates to the synergistic or antagonist effects of molecules present, various polyphenols and triterpenes being identified in the extracts studied in this research.  相似文献   

11.
The present research assessed the radical scavenging activity against the synthetic 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl radical of the water-saturated 1-butanol extracts of wholemeal flour from 63 Triticum monococcum accessions, which originated from different eco-geographical areas. On average, T. monococcum had higher radical scavenging activity than T. turgidum and T. aestivum species, which served as controls (0.90, 0.64 and 0.70 mmol TE/kg DM, for T. monococcum, T. turgidum and T. aestivum, respectively). A significant correlation between radical scavenging activity and tocol content was observed, while no correlation existed with soluble phenolics and carotenoid contents.  相似文献   

12.
The objectives of this study were to examine the free radical scavenging activity and the protective effects against macromolecular oxidation as well as the cytotoxic activity of Aphanes arvensis aqueous and methanolic extracts. Free radical scavenging activity was determined by DPPH method. The methanolic extract showed a scavenging activity nearly equivalent to Trolox and Vitamin C and has an IC50 value of 4.54 μg/mL. Total antioxidant capacity was determined by CUPRAC method. The antioxidant capacity of aqueous and methanolic extract was 0.792 and 1.550 mmol TE/g DWE, respectively. The protective effect of A. arvensis extracts against lipid peroxidation was evaluated using a liposome oxidation system. The methanolic extract was more active than the aqueous extract. The aqueous extract possessed protective effect against protein oxidation in a dose dependent manner. Both extracts showed inhibitory effect on DNA oxidation as measured by plasmid relaxation assay. Results presented here indicate that A. arvensis possess strong antioxidant activity and protective effects with very little cytotoxic effect, and they can therefore be used as a natural additive in food, cosmetic and pharmaceutical industries.  相似文献   

13.
The hydro-alcoholic extracts of five Equisetum species, E. arvense L., E. sylvaticum L., E. fluviatile L., E. palustre L. and E. telmateia Ehrh., growing-wild in Serbia were evaluated for their genotoxicity, antimicrobial activity, antioxidant capacity and the results related to the total phenol content and HPLC flavonoid profiles. The total phenol content was 92–349 μmol expressed as equivalents of chlorogenic acid per g of dried plant material. Main identified compounds were kaempferol-, quercetin- glycosides and caffeic acid derivatives. E. telmateia extract showed the greatest antioxidant capacity. Almost all tested microorganisms demonstrated some degree of sensitivity to the examined extracts. All tested extracts at 62.5 μg/ml showed higher incidence of micronucleus formation than in the control sample. The obtained data allowed mutual comparison of examined species and their assessment as possible sources of antioxidants, antimicrobials and/or genotoxic substances.  相似文献   

14.
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   

15.
An analytical study was carried out on the presence of antioxidant constituents and the in vitro antioxidant capacity in the extracts of three species of Spanish red-skinned cactus pear fruits (Opuntia ficus-indica, Opuntia undulata and Opuntia stricta). The cactus pear fruit extracts were analyzed for determined constituents: ascorbic acid, flavonoids (quercetin, isorhamnetin, myricetin, kaempferol and luteolin), betalains, taurine, total carotenoids and total phenolics. The antioxidant capacity was assessed by means of two different methods: the 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (Trolox equivalent antioxidant capacity) method and the 2,2-diphenyl-1-picrylhydrazyl radical method. Opuntia ficus-indica fruit extract had the strongest antioxidant capacity and taurine content. O. stricta fruits were the richest in ascorbic acid and total phenolics, whereas O. undulata fruits showed the highest carotenoid content. Quercetin and isorhamnetin were the main flavonoids detected. This study provides basic information on the presence of bioactive compounds and antioxidant capacity in extracts of cactus pear fruits, in order to consider these extracts as ingredient for the production of health-promoting food.  相似文献   

16.
We investigated the influence of the growth season of Artemisia princeps var. orientalis (PAMPAN.) HARA on antimicrobial and antioxidative activities. The ethyl acetate and water fractions of crude methanol extract from the plant collected monthly (April through October) were tested against three gram-positive, two gram-negative bacteria and one lactic acid bacterium. The ethyl acetate and water fractions of crude methanol extract from A. princeps var. orientalis collected in August and September had the highest antimicrobial activity. The antimicrobial activity of extract from A. princeps var. orientalis for Lactobacillus plantarum was not found at any concentration and in any growth season. Minimum inhibitory concentration (MIC) for each strain by ethyl acetate fraction of methanol extract from A. princeps var. orientalis was different depending on the tested strain and growth season of the plant. MIC for each strain was the highest in the sample from April, followed by October. The antioxidative activities of methanol extracts from A. princeps var. orientalis collected monthly were measured by their scavenging activity on free radical of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and xanthine oxidase (XO) inhibitory activity. The DPPH radical scavenging activities of the extracts from the plants collected in May, June and July were higher than any other. The XO inhibitory activities of the extracts of A. princeps var. orientalis collected in April and May showed the greatest activity, it is different with antimicrobial activity. This is the first report that antimicrobial and antioxidative activity of the extracts of A. princeps var. orientalis is different with growth season.  相似文献   

17.
Codium bernabei is a green alga that grows on Chilean coasts. The composition of its structural polysaccharides is still unknown. Hence, the aim of this work is to isolate and characterize the hot water extracted polysaccharide fractions. For this purpose, the water extracts were further precipitated in alcohol (TPs) and acid media (APs), respectively. Both fractions were characterized using different physicochemical techniques such as GC-MS, GPC, FTIR, TGA, and SEM. It is confirmed that the extracted fractions are mainly made of sulfated galactan unit, with a degree of sulfation of 19.3% (TPs) and 17.4% (ATs) and a protein content of 3.5% in APs and 15.6% in TPs. Other neutral sugars such as xylose, glucose, galactose, fucose, mannose, and arabinose were found in a molar ratio (0.05:0.6:1.0:0.02:0.14:0.11) for TPs and (0.05:0.31:1.0:0.03:0.1:0.13) for ATs. The molecular weight of the polysaccharide samples was lower than 20 kDa. Both polysaccharides were thermally stable (Tonset > 190 °C) and showed antioxidant activity according to the ABTS•+ and DPPH tests, where TPs fractions had higher scavenging activity (35%) compared to the APs fractions. The PT and APTTS assays were used to measure the anticoagulant activity of the polysaccharide fractions. In general, the PT activity of the TPs and APs was not different from normal plasma values. The exception was the TPs treatment at 1000 µg mL−1 concentration. The APTTS test revealed that clotting time for both polysaccharides was prolonged regarding normal values at 1000 µg mL−1. Finally, the antitumor test in colorectal carcinoma (HTC-116) cell line, breast cancer (MCF-7) and human leukemia (HL-60) cell lines showed the cytotoxic effect of TPs and APs. Those results suggest the potential biotechnological application of sulfate galactan polysaccharides isolated from a Chilean marine resource.  相似文献   

18.
Aerial parts (leaves and stem) of Raphanus sativus, which are usually discarded were found to possess potent antioxidant and radical scavenging activity, as measured by standard antioxidant assays. Methanolic and acetone extracts of R. sativus leaves had total polyphenolic content of 86.16 and 78.77 mg/g dry extract, which were comparable to the traditional rich sources such as green tea and black tea. HPLC identification of polyphenolics indicated the presence of catechin, protocatechuic acid, syringic acid, vanillic acid, ferulic acid, sinapic acid, o-coumaric acid, myricetin, and quercetin in leaves and stem. Among the different extraction solvents, methanolic extract of leaves and stem showed potent reductive capacity, significantly inhibited linoleic acid peroxidation and displayed metal chelating activity. Further, they scavenged free radicals effectively with IC50 (half maximal inhibitory concentration) of 31 and 42 μg/ml for DPPH radical, 23 and 52 μg/ml for superoxide radical, 67 and 197 μg/ml for hydrogen peroxide, and 56 and 62 μg/ml for nitric oxide, respectively. Leaves showed most potent antioxidant and radical scavenging activity as compared to stem, which may be accounted for the high polyphenolic content. Leaves and stem of R. sativus, often under-utilized part of this vegetable, thus possessed considerable amount of polyphenolics. Hence, it should be regarded as a potential source of natural antioxidants and could be effectively employed as an ingredient in health or in functional food.  相似文献   

19.
Annona diversifolia is a Central America native fruit which has become an important crop because of its tasty flavor, high pulp content, nutritional value and antioxidant properties. Color, crude protein, crude fat, crude fiber, ash, minerals, pH, titratable acidity, and carbohydrate contents were determinated in white, pink and deep pink varieties of A. diversifolia. Our results show that the three studied varieties of A. diversifolia could be considered as important sources of fiber, sugars, potassium and zinc. Color measuring was successfully used to objectively characterize the three A. diversifolia varieties, resulting in an excellent agreement with visual observations. The antioxidant activity also was determined and compared. An in vitro study was conducted in terms of vitamin C, total phenols, total flavonoids, and radical scavenging activity. A strong correlation between total polyphenols and radical scavenging activity was observed. This paper reports for the first time the total flavonoid content of Annona genus fruits. In addition, A. diversifolia extracts possessed greater radical scavenging activity and similar total polyphenol content compared to those of other Annona species reported elsewhere.  相似文献   

20.
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   

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