首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Huang WY  Cai YZ  Xing J  Corke H  Sun M 《Planta medica》2008,74(1):43-49
Many species of Polygonum are rich in bioactive constituents, which contribute to a wide range of medicinal properties. In this study, we assessed the scavenging activity against ABTS.+ and hydroxyl radicals, chelating activity against Fe2+, xanthine oxidase inhibition, antimicrobial activity, and total contents of phenolics and flavonoids in the extracts of leaves and stems or whole plants from four medicinal Polygonum species. Total antioxidant capacities and phenolic contents of Polygonum capitatum, Polygonum Chinensis, Polygonum cuspidatum, and Polygonum multiflorum were 74.60, 53.66, 56.22, and 14.34 mmol trolox/100 g dry weight (DW), and 8.69, 4.15, 6.33, and 1.27 g gallic acid/100 g DW, respectively, significantly higher than those of five dietary vegetables, fruits and spices (spring onion, broccoli, orange, carrot, and ginger). Major bioactive constituents in the tested plant extracts were also investigated using LC-MS. They were mainly phenolic compounds, e. g., flavonoids, phenolic acids and their derivatives, tannins, stilbenes, and anthraquinones. This study shows that, in addition to their roots, the leaves and stems of P. cuspidatum and P. capitatum also exhibit potent antioxidant properties and are a potential resource of natural bioactive antioxidants.  相似文献   

2.
Different conventional and “green” extraction techniques (solid/liquid extraction, microwave and ultrasound assisted extraction, pressurized liquid extraction and subcritical water extraction) were tested using different operating conditions in the recovery of valuable polyphenol compounds from sugar beet leaves. All tested extraction techniques provided considerable extraction yield in the range from 18.21% to 37.04%. Total phenolic content ranged from 0.4504 up to 1.7171 (g GAE/100 g DW) with the highest values obtained by using microwave and ultrasound assisted extraction. Extraction parameters had highly significant effect on the concentration of bioactive compounds recovered by pressurized liquid extraction and subcritical water extraction. Individual phenolic profile of sugar beet leaves extracts largely depended on the applied extraction technique, however, vitexin was the most abundant phenolic compound present in all extracts regardless of the extraction technique. Investigation of extracts antioxidant activity through DPPH, FRAP and ABTS values indicated the lowest antioxidant activity of extracts obtained by solid/liquid extraction compared to other extraction techniques.  相似文献   

3.
Flavonoids and phenolic acids isolated from the herbs of Melampyrum pretense (MP) and M. nemorosum (MN) (Scrophulariaceae) growing in the Ural region have been studied by two-dimensional paper chromatography. The phenolic complex of MP contains 23 compounds including 17 flavonoids and 6 phenolcarboxylic acids. The MN herb contains 9 flavonoids and 5 phenolcarboxylic acids. A comparison with reference samples showed the presence of cinaroside, luteolin, quercetin, hyperoside, and chlorogenic, caffeic, and ferulic acids. Differential UV spectra of the extracts of MP and MN herbs in the presence of aluminum chloride showed peaks at 395.6 and 398.7 nm, respectively, which have been used for quantitative determination of the flavonoids (recalculated for cinaroside). The maximum flavonoid content was found in the generative organs; the minimum, in the roots. It is established that the flavonoid content in various organs varies within 0.08–3.17% for MP and 0.04–2.29% for MN.  相似文献   

4.
Buriti (Mauritia flexuosa L.) is a palm tree found in several regions of Latin America. Buriti fruit is a rich source of bioactive compounds such as carotenoids and phenolic compounds. Thus, the aim of this study was to extract bioactive compounds from buriti fruit by ethanol and a supramolecular solvent system (SUPRAS) formed by octanoic acid aggregates. The extracts were evaluated for total carotenoids, β-carotene, phenolic compounds and antioxidant capacity. Additionally, SUPRAS extracts were characterized for antibacterial activity and modulating effect. The extraction of β-carotene with SUPRAS showed a yield of 5.82 ± 0.05 mg/g for the peel and 26.7 ± 0.02 mg/g for the pulp. In relation to total phenolic compounds, the yields were 32.1 ± 1.2 μg GAE/g for the peel and 24.53 ± 4.9 μg GAE/g for the pulp. The presence of gallic acid, quercetin and catechin stand out regarding the phenolics identified. The extracts showed antioxidant activity, with an emphasis on the extracts obtained by SUPRAS, which presented EC50 (concentration required to obtain a 50% antioxidant effect) for the ABTS radical sequestration of 3.00 μg/mL for the peel and 0.84 μg/mL for the pulp. When combined with norfloxacin and gentamicin antibiotics, the extracts also showed a synergistic action against multi-resistant strains of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. Thus, the extraction of bioactive compounds from buriti fruit using a safe, biocompatible, biodegradable and environmentally friendly solvent such as SUPRAS represents potential for developing new pharmaceuticals, cosmetics and functional foods.  相似文献   

5.
A 50% ethanolic extract (MCS-ext) from seeds of Morinda citrifolia (“noni” seeds) showed more potent in vitro inhibition of elastase and tyrosinase, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity than extracts of M. citrifolia leaves or flesh. Activity-guided fractionation of MCS-ext using in vitro assays led to the isolation of ursolic acid as an active constituent of elastase inhibitory activity. 3,3′-Bisdemethylpinoresinol, americanin A, and quercetin were isolated as active constituents having both tyrosinase inhibitory and radical scavenging activities. Americanin A and quercetin also showed superoxide dismutase (SOD)-like activity. These active compounds were isolated from noni seeds for the first time.  相似文献   

6.
Hydrodistilled volatile oil from the seeds of Zizyphus jujuba was analyzed by GC–MS. Twenty three compounds representing 91.59% of the total oil was identified. The oil and organic extracts revealed a great potential of antilisterial effect against all five strains of Listeria monocytogenes ATCC 19111, 19116, 19118, 19166 and 15313. Also the oil had strong detrimental effect on the viable count of the tested bacteria. The samples were also subjected to screening for the antioxidant activity by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radicals scavenging activities assay. In the first case, the IC50 value of the Z. jujuba essential oil was determined to be 5.21 ± 0.01 μg/ml. Among the extracts, the strongest activity was exhibited by the methanol extract with an IC50 value of 20.44 ± 0.18 μg/ml. In the superoxide radicals scavenging activities assay, methanol extract was superior to all other extracts (IC50 = 18.60 ± 0.3 μg/ml). Furthermore, the amount of total phenolic compounds was determined. The results indicate that the essential oil and extracts of Z. jujuba could serve as natural antimicrobial and antioxidant agents for the food industry.  相似文献   

7.
Limnophila aromatica is commonly used as a spice and a medicinal herb in Southeast Asia. In this study, water and various concentrations (50%, 75%, and 100%) of methanol, ethanol, and acetone in water were used as solvent in the extraction of L. aromatica. The antioxidant activity, total phenolic content, and total flavonoid content of the freeze-dried L. aromatica extracts were investigated using various in vitro assays. The extract obtained by 100% ethanol showed the highest total antioxidant activity, reducing power and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity. The same extract also exhibited the highest phenolic content (40.5 mg gallic acid equivalent/g of defatted L. aromatica) and the highest flavonoid content (31.11 mg quercetin equivalent/g of defatted L. aromatica). The highest extraction yield was obtained by using 50% aqueous acetone. These results indicate that L. aromatica can be used in dietary applications with a potential to reduce oxidative stress.  相似文献   

8.
Different cultivars of walnut (Juglans regia L.) leaves (Cv. Lara, Franquette, Mayette, Marbot, Mellanaise and Parisienne) grown in Portugal, were investigated in what concerns phenolic compounds and antimicrobial and antioxidant properties. Phenolics analysis was performed by reversed-phase HPLC/DAD and 10 compounds were identified and quantified: 3- and 5-caffeoylquinic acids, 3- and 4-p-coumaroylquinic acids, p-coumaric acid, quercetin 3-galactoside, quercetin 3-pentoside derivative, quercetin 3-arabinoside, quercetin 3-xyloside and quercetin 3-rhamnoside. The antimicrobial capacity was screened against Gram positive (Bacillus cereus, B. subtilis, Staphylococcus aureus) and Gram negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae) and fungi (Candida albicans, Cryptococcus neoformans). Walnut leaves selectively inhibited the growth of Gram positive bacteria, being B. cereus the most susceptible one (MIC 0.1mg/mL). Gram negative bacteria and fungi were resistant to the extracts at 100mg/mL. Lara walnut leaves were also submitted to antibacterial assays using 18 clinical isolates of Staphylococcus sp. Antioxidant activity was accessed by the reducing power assay, the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and beta-carotene linoleate model system. In a general way, all of the studied walnut leaves cultivars presented high antioxidant activity (EC(50) values lower than 1mg/mL), being Cv. Lara the most effective one.  相似文献   

9.
Arctium lappa, commonly known as burdock, is being promoted/recommended as a healthy and nutritive food in Chinese societies. Burdock has been used therapeutically in Europe, North America and Asia for hundreds of years. The roots, seeds and leaves of burdock have been investigated in view of its popular uses in traditional Chinese medicine (TCM). In this review, the reported therapeutic effects of the active compounds present in the different botanical parts of burdock are summarized. In the root, the active ingredients have been found to “detoxify” blood in terms of TCM and promote blood circulation to the skin surface, improving the skin quality/texture and curing skin diseases like eczema. Antioxidants and antidiabetic compounds have also been found in the root. In the seeds, some active compounds possess anti-inflammatory effects and potent inhibitory effects on the growth of tumors such as pancreatic carcinoma. In the leaf extract, the active compounds isolated can inhibit the growth of micro-organisms in the oral cavity. The medicinal uses of burdock in treating chronic diseases such as cancers, diabetes and AIDS have been reported. However, it is also essential to be aware of the side effects of burdock including contact dermatitis and other allergic/inflammatory responses that might be evoked by burdock.  相似文献   

10.
In earlier experiments, the MDR (multidrug resistance)-reversal activities of Anastasia Black (Russian black sweet pepper) extracts had been analysed. Recently, the most effective MDR reversing extracts and fractions have been separated by HPLC (high-performance liquid chromatography, for carotenoids) and LC-MS-MS (HPLC combined with mass spectrometry, for phenolic compounds) methods. As a result of the analytical studies, the following flavonoids had been identified: feruloyl glucopyranoside, quercetin rhamnopyranoside glucopyranoside, luteolin glucopyranoside arabinopyranoside, apigenin glucopyranoside arabinopyranoside, quercetin rhamnopyranoside, luteolin arabinopyranoside diglucopy-ranoside, hesperidine and luteolin glucuronide. According to the literature, the aglycones of these phenolic compounds exhibit MDR-reversal activity in vitro, and the connection between the phenolic content of Anastasia Black and MDR-reversal action was therefore studied by different analytical methods. The results of this study revealed that the identified flavonoids of Anastasia Black may be only partially responsible for the modulation of the MDR of mouse lymphoma cells. Other lipophilic compounds, most probably carotenoids, present in Russian black sweet pepper may act as inhibitors of MDR reversal.  相似文献   

11.
Evaluation of the antiviral activities of flowers, flower-peduncles, leaves, and roots of Aloe hijazensis against haemagglutinating viruses of avian paramyxovirus type-1 (APMV-1), avian influenza virus type A (AI-H5N1), Newcastle disease virus (NDV), and egg-drop syndrome virus (EDSV) in specific pathogen free (SPF) chicken embryos were carried out. Extract of the flowers and leaves showed relatively higher activity than the extracts of other plant parts. Thirteen compounds were isolated from both the flowers and flower-peduncles of A. hijazensis. The isolated compounds were classified into: five anthraquinones; ziganein, ziganein-5-methyl ether, aloesaponarin I, chrysophanol, aloe-emodin, one dihydroisocoumarin; feralolide, four flavonoids; homoplantaginin, isoorientin, luteolin 7-glucuronopyranoside, isovitexin, one phenolic acid; p-coumaric acid, the anthrone; barbaloin together with aloenin. Eleven compounds were attributed to the flowers and seven to the flower-peduncles. Homoplantaginin and luteolin 7-glucuronopyranoside are reported here for the first time from Aloe spp. To the best of our knowledge, this is the first report on the chemical composition and biological activity of those plant parts.  相似文献   

12.
The objective of this research was to access the determination of metabolite profiles and antioxidant properties in the leaves of green perilla (Perilla frutescens), where these are considered functional and nutraceutical substances in Korea. A total of 25 compositions were confirmed as six phenolic acids, two triterpenoids, eight flavonoids, seven fatty acids, and two glucosides using an ultra high performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-ESI-Q-TOF-MS/MS) technique from the methanol extract of this species. The individual and total compositions exhibited significant differences, especially rosmarinic acid (10), and linolenic acids (22 and 23) were detected as the predominant metabolites. Interestingly, rosmarinic acid (10) was observed to have considerable differences with various concentrations in three samples (Doryong, 6.38 μg/g; Sinseong, 317.60 μg/g; Bongmyeong, 903.53 μg/g) by UPLC analysis at 330 nm. The scavenging properties against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radicals also showed potent effects with remarkable differences at a concentration of 100 μg/mL, and their abilities were as follows: Sinseong (DPPH, 86%; ABTS, 90%) > Bongmyeong (71% and 84%, respectively) > Doryong (63% and 73%, respectively). Our results suggest that the antioxidant activities of green perilla leaves are correlated with metabolite contents, especially the five major compositions 10 and 22–25. Moreover, this study may be useful in evaluating the relationship between metabolite composition and antioxidant activity.  相似文献   

13.
An investigation was carried out to extract polyphenols from the peel of kinnow (Citrus reticulate L.) by maceration and ultrasound-assisted extraction (UAE) techniques. The antioxidant potential of these polyphenols was evaluated using ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and superoxide radical scavenging assays; and their antimicrobial activity was assessed against bacterial strains Staphyloccoccus aureus, Bacillus cereus, and Salmonella typhimurium. The highest extraction yield was obtained through the solvent ethanol at 80% concentration level, whereas UAE was a more efficient technique and yielded comparatively higher polyphenol contents than maceration. Maximum polyphenols were extracted with 80% methanol [32.48 mg gallic acid equivalent (GAE)/g extract] using UAE, whereas minimum phenolics (8.64 mg GAE/g extract) were obtained with 80% ethyl acetate through the maceration technique. Elevated antioxidant activity of kinnow peel extracts was exhibited in three antioxidant assays, where 80% methanolic extracts showed the highest antioxidant activity (27.67 ± 1.11mM/100 g for FRAP) and the highest scavenging activity, 72.83 ± 0.65% and 64.80 ± 0.91% for DPPH and superoxide anion radical assays, respectively. Strong correlations between total polyphenols and antioxidant activity were recorded. Eleven phenolic compounds—including five phenolic acids and six flavonoids—were identified and quantified by high performance liquid chromatography. Ferulic acid and hesperidin were the most abundant compounds whereas caffeic acid was the least abundant phenolic compound in kinnow peel extracts. Maximum inhibition zone was recorded against S. aureus (16.00 ± 0.58 mm) whereas minimum inhibition zone was noted against S. typhimurium (9.00 ± 1.16 mm). It was concluded that kinnow mandarin peels, being a potential source of phenolic compounds with antioxidant and antimicrobial properties, may be used as an ingredient for the preparation of functional foods.  相似文献   

14.
Pharmaceutical Chemistry Journal - Aqueous extracts of nettle leaves (100 mg/kg) and greater burdock roots (25 mg/kg) decreased the blood levels of glucose, triglycerides, total cholesterol, and...  相似文献   

15.
Crude composition, fatty acids, sterols, total phenolic content (TPC), individual polyphenols and terpenic acids were determined in five wild edible mushrooms species (Lactarius deliciosus, Lactarius sanguifluus, Lactarius semisanguifluus, Russula delica, Suillus bellinii) from Lesvos Island, Greece. In addition, the DPPH scavenging capacity, the ferric ion reducing power (FRAP) and the ferrous ion chelating activity of mushroom methanolic extracts were assessed. Among sterols, ergosterol predominated at concentrations 9.2–18.0 mg/100 g fw. Total phenolic content of mushroom extracts ranged from 6.0 to 20.8 mg GAE/100 g fw. Up to 19 simple polyphenols were determined in mushrooms extracts, the more abundant being p-OH-benzoic acid, p-OH-phenylacetic acid, o-coumaric acid, ferulic acid and chrysin. In addition, the triterpenic acids oleanolic and ursolic were detected for the first time in mushrooms. All species exerted antioxidant activity and ferrous ion chelating capacity. Principal component analysis revealed good correlations between TPC, DPPH and FRAP but not with metal chelating activity. It seems that mushrooms polyphenols exert antiradical and reducing activities, but they are not strong metal chelators, the observed chelating ability being probably due to other classes of compounds.To our knowledge, this is the first report on the bioactive microconstituents and antioxidant activity of wild Greek edible mushrooms.  相似文献   

16.
Leaf of Salvia miltiorrhiza Bunge, the waste part during the root harvest, is rich in health-promoting phenolics and is a novel resource of natural antioxidants. The acetone and methanol extracts of leaves (AL and ML, respectively) of S. miltiorrhiza were evaluated by various in vitro antioxidant assays. The total phenolic contents of AL and ML were 39.0 ± 1.13 and 54.3 ± 1.1 mg gallic acid equivalents/g extract tested, respectively. EC50 of ML was 7.0 ± 0.28 μg/mL in DPPH radical scavenging assay and 246.5 ± 10.35 μg/mL in superoxide radical quenching assay. It was also found that ML has prominent effects on the inhibition of linoleic acid oxidation (93.2%), which was equivalent to the positive control, butylated hydroxytoluene (BHT, p > 0.05), and was significantly higher than α-tocopherol (VE, p < 0.05). The reducing power of leaf extracts was as strong as roots (p > 0.05). HPLC and correlation analysis show that salvianolic acid B and rosmarinic acid constitute the most abundant phenolic compounds. They are the major contributors to antioxidant activities. The results suggested that S. miltiorrhiza leaves could be considered as a new potential source of natural phenolic antioxidants for food, pharmaceutical, cosmetics or nutraceutical industries.  相似文献   

17.
Heating effect on total phenol, flavonoids, antioxidant activity, and sugar content of six onion varieties has been quantitatively investigated to explore the effect of different temperatures. The onion varieties comprised one red-skinned variety, two white-skinned varieties, and three yellow-skinned varieties. The heating temperature was scanned at 80°C, 100°C, 120°C, and 150°C for 30 minutes each, and quantitative analysis was performed relative to the powdered onion at ambient temperature. Quercetin, glucosides and sugar content were analyzed using high-performance liquid chromatography. The total phenolic and antioxidant content increased in all six varieties. The total flavonoid levels showed a considerable change. On heating the onion samples at 120°C for 30 minutes, the red-skinned variety showed the highest level of total phenolic content [13712.67 ± 1034.85 μg of gallic acid equivalent/g dry weight (μg GAE/g DW)] and total flavonoids [3456.00 ± 185.82 μg of quercetin equivalents/g dry weight (μg Q/g DW)], whereas the content of total phenolics and total flavonoids were 13611.83 ± 341.61 μg GAE/g DW and 3482.87 ± 117.17 μg Q/g DW, respectively, for the yellow-skinned (Sunpower) variety. Quercetin and its glucoside contents increased up to 120°C and then decreased at 150°C, whereas the sugar content continuously decreased with heating. All cultivars showed the same pattern in the heating effect, and the predominant flavonoids were destroyed at higher temperatures. Therefore, it is improper to expose onion powder to a temperature higher than 120°C.  相似文献   

18.
The health benefits of fruits acting against chronic diseases are ascribed to their antioxidant activities which are mainly responsible due to the presence of phenolic compounds. The use of ultra-high-pressure-assisted extraction (UHPE) has shown great advantages for the extraction of these phenolic compounds from longan fruit pericarp (LFP). Studies were carried out to investigate the effects of UHPE at pressures of 200, 300, 400 and 500 MPa on total phenolic contents, extraction yield, antioxidant and antityrosinase activities from LFP. The antioxidant activities of these extracts were analyzed, using various antioxidant models like 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, total antioxidant capacity and superoxide anion radical scavenging activity. Extract from ultra-high-pressure-assisted extraction at 500 MPa (UHPE-500) showed the highest antioxidant activities of all the tested models. In addition, it also showed moderate tyrosinase inhibitory activity. Three phenolic acids, namely gallic acid, ellagic acid, and corilagin were identified and quantified by HPLC. Corilagin content was the highest compared to other phenolic acids identified. UHPE-500 obtained the higher phenolic acid contents compared to other high pressure processing and conventional extractions (CE). Compared with CE, UHPE-500 exhibited good extraction effectiveness in terms of higher extraction yields with high phenolic contents and also with higher antioxidant and antityrosinase activities.  相似文献   

19.
As part of our continuing investigation for interesting biological activities of native medicinal plants, thirty-nine plants, obtained from diverse areas in Saudi Arabia and Yemen, were screened for insecticidal activity against yellow fever mosquito Aedes aegypti (L.). Out of the 57 organic extracts, Saussurea lappa, Ocimum tenuiflorum, Taraxacum officinale, Nigella sativa, and Hyssopus officinalis exhibited over 80% mortality against adult female Ae. aegypti at 5 μg/mosquito. In the larvicidal bioassay, the petroleum ether extract of Aloe perryi flowers showed 100% mortality at 31.25 ppm against 1st instar Ae. aegypti larvae. The ethanol extract of Saussurea lappa roots was the second most active displaying 100% mortality at 125 and 62.5 ppm. Polar active extracts were processed using LC-MS/MS to identify bioactive compounds. The apolar A. perryi flower extract was analyzed by headspace SPME-GC/MS analysis. Careful examination of the mass spectra and detailed interpretation of the fragmentation pattern allowed the identification of various biologically active secondary metabolites. Some compounds such as caffeic and quinic acid and their glycosides were detected in most of the analyzed fractions. Additionally, luteolin, luteolin glucoside, luteolin glucuronide and diglucuronide were also identified as bioactive compounds in several HPLC fractions. The volatile ketone, 6-methyl-5-hepten-2-one was identified from A. perryi petroleum ether fraction as a major compound.  相似文献   

20.
This study evaluated antioxidant, anti-inflammatory, anti-cholinesterase and cytotoxic activities of extracts with different polarities (hexane, dichloromethane, ethyl acetate, ethanol and methanol) obtained from Punica granatum leaves. Total phenolics (8.8–127.3 mg gallic acid equivalent/g dry weight), flavonoids (1.2–76.9 mg quercetin equivalent/g dry weight), tannins (63.7–260.8 mg catechin equivalent/kg dry weight) and anthocyanins (0.41–3.73 mg cyanidin-3-glucoside equivalent/g dry weight) of different extracts were evaluated. The methanolic extract presented a good IC50 by DPPH and ABTS assays (5.62 and 1.31 mg/l respectively). The strongest 5-lipoxygenase (5-LOX), acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibition activities were obtained for the ethanol extract (IC50 values of 6.20, 14.83 and 2.65 mg/l, respectively) and the best cytotoxic activity against MCF-7 cells was obtained for the methanol extract (IC50 = 31 mg/l). These important biological activities showed that P. granatum leaves could be a potential source of the active molecules intended for applications in pharmaceutical industry, but only after additional in vivo experiments.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号