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1.
Flavonoids have many positive effects on various cell layers of the skin (e.g. anti-oxidant, anti-allergic and anti-inflammatory effects). However, the limiting factor of the use of flavonoids is their low water solubility. To overcome the poor solubility, apigenin nanosuspensions were prepared using the combination technology (CT), i.e. bead milling and subsequently high pressure homogenization. Distinct reduction in particle size was observed after each bead milling passage resulting in z-average (PCS) of 413 nm and a polydispersity index of 0.202. The LD data showed a similar pattern of particle size reduction reaching a diameter 99% (d(v)99%) of 0.515 μm. The antioxidant capacity of apigenin nanocrystals were almost doubled compared to the original coarse suspension. The developed smartCrystals can be easily incorporated into gels, which makes apigenin nanocrystals available for dermal application as efficient antioxidant.  相似文献   

2.
The powder samples and methanol extract of 11 medicinal plants were subjected to analysis of proximate composition and measurement of antioxidant activity. Different parameters studied include phenolic contents, moisture, ash, crude fiber, fats and waxes. The assays employed were ferric reducing antioxidant power, trolox equivalent antioxidant capacity and scavenging effect on the 1,1-diphenyl-2-picrylhydrazyl free radical. Results obtained indicate that the antioxidant potential varied significantly from plant to plant. The total phenolic contents were determined spectrophotometrically using Folin-Ciocalteu reagent. Significant correlation is observed between ferric reducing antioxidant power and phenolic contents (R(2) = 0.96). These findings show that the polyphenolic constituents in the extracts are responsible for free radical scavenging capacity.  相似文献   

3.
Hydromethanolic extracts from 18 Algerian medicinal plants were screened for their phenolic contents and radical scavenging activities. The phenolic extract of Cleome arabica (Capparaceae) was found to be the most active one. Purification of this extract by semi-preparative high performance liquid chromatography led to the isolation and identification of new steroid derivative. The structure of the active principle is proposed as (17-(4-hydroxy-1,5-dimethylhexyl)-2,3,7-(acetyloxy) gona-1,3,5(10)-trien-15-ol). Compared to six other standard antioxidants which were ascorbic acid, α-tocopherol, Trolox, (+) catechin, p-coumaric acid and gallic acid, the isolated compound was found to be significantly more active in the radical scavenging assay using 2,2-diphenyl-1-picrylhydrazyl (DPPH). Similar results were obtained in the hemolysis assay. The antioxidant capacities of the methanolic extract of C. arabica and its principle compound indicate that this plant may be an important source of chemopreventive and chemotherapeutic natural products activity.  相似文献   

4.
目的 评价子痫前期患者与正常孕妇的脂质过氧化和抗氧化状态的变化.方法 68例女性,年龄23~35岁,分为3组.A组23例为血压正常孕妇,孕期28~39周.B组26例为子痫前期孕妇,孕期28~39周.C组19例为血压正常的健康未孕女性.所有女性均检测血浆丙二醛(MDA)水平来评价机体的脂质过氧化、血浆抗氧化酶超氧化物歧化酶(SOD)、谷胱甘肽过氧化酶、过氧化氢酶以及抗氧化物还原型谷胱甘肽(GSH)和维生素C的水平.结果 B组脂质过氧化水平明显增高.与C组相比A组和B组GSH水平均明显降低而SOD水平均明显升高(P<0.01).与C组相比,A组血浆过氧化氢酶、谷胱甘肽过氧化酶等抗氧化酶水平明显降低(P<0.01).作为抗氧化物的维生素C的水平,与A组和C组比较B组明显升高(P<0.01).结论 机体的先天性抗氧化系统可以对抗子痫前期诱发的氧化应激反应.  相似文献   

5.
头状蓼提取物体外抗氧化活性研究   总被引:1,自引:0,他引:1  
目的:研究头状蓼提取物的体外抗氧化活性。方法:以脂溶性维生素E及二丁基羟基甲苯(BHT)作对照,采用清除二苯代苦味酰基(DPPH)自由基、清除[2,2′-连氨-(3-乙基苯并噻唑啉-6-磺酸)二氨盐](ABTS)自由基和铁离子(Fe3+)还原/抗氧化能力(FRAP)测定法检测头状蓼石油醚、乙酸乙酯、甲醇提取物的体外抗氧化活性。结果:与头状蓼石油醚、乙酸乙酯提取物比较,头状蓼甲醇提取物清除DPPH自由基、清除ABTS自由基及还原Fe3+的能力较强。结论:头状蓼甲醇提取物具有较好的体外抗氧化活性。3种方法中,DPPH方法和ABTS方法相关性最高。  相似文献   

6.
We characterized the biological functions of protocatechualdehyde (PA) isolated from the butanol extract of culture supernatant from Streptomyces lincolnensis M-20. Following butanol extraction, it was purified by silica gel and Sephadex LH-20 column chromatography. PA was analyzed by Furier Transform Infrared Spectroscopy (FT-IR), Gas chromatograph-Mass Spectrometer (GC-MS), and Nuclear Magnetic Resonance (NMR). PA had potent antioxidant activity, as measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. Antitumor activity against MCF-7 human breast cancer cells was evaluated by the 3-(4,5-dimethylthazol-2-yl)-2,5-diphenyl tetrazolium-bromide (MTT) assay. PA treatment (0∼150 μM) dose-dependently blocked apoptosis, as shown by improved cell viability and inter-nucleosomal DNA fragmentation. Our findings suggest that Streptomyces lincolnensis M-20, a lincomycin producer, also produces protocatechualdehyde.  相似文献   

7.
The antioxidant activity of Artemisia montana was determined by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and inhibitory activity against free radical generation of hepatocytes (AC2F). The methanol extract of A. montana showed strong radical scavenging activity at a concentration of 10.1 microg/ml, and thus fractionated by solvent extraction. Esculetin and luteolin 7-O-rutinoside (scolymoside) were isolated as the active principles from the EtOAc and Interphase fractions, respectively. The antioxidant activity of these compounds were comparable to that of L-ascorbic acid.  相似文献   

8.
Purpose: The aim of the paper was to develop the simple procedures for preparation of inclusion complexes of ellagic acid (EA) with cyclodextrins (CDs) and to investigate their antioxidant and antimicrobial activity.

Methods: The structural characterization was carried out using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and nuclear magnetic resonance (NMR) methods. The phase solubility technique was used to investigate the interactions between ‘host’ and ‘guest’ molecules and to estimate the molar ratio between them. The antioxidant and antimicrobial activity of EA and inclusion complexes were determined.

Results: The apparent stability constants were found to be 117?dm3 mol?1 for the complex with β-CD and 161?dm3 mol?1 for the complex with (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD). The results of phase-solubility studies showed that EA formed the inclusion complexes with CDs in the molar ratio of 1:1. The calculated half-maximal inhibitory concentration was 41.18?μg cm?3 for butyl hydroxy toluene, 1.96?μg cm?3 for EA, 0.88?μg cm?3 for inclusion complex with HP-β-CD, and 1.27?μg cm?3 for inclusion complex with β-CD.

Conclusion: The stability constants indicated the rapid release of EA from the inclusion complexes in the aqueous medium at 25?°C. The antioxidant activity of EA was increased, while the antimicrobial activity was preserved after complexation with CDs.  相似文献   


9.
ContextTraditionally, Oleaceae plants are used to treat many diseases, such as rheumatism, hypercholesterolaemia, or ulcers.ObjectivesTo investigate the cytotoxic potential of Jasminum humile L., Jasminum grandiflorum L., and Olea europaea L. (Oleaceae) extracts against selected human cancer cells lines, followed by a phytochemical investigation of the most potent one.Materials and methodsThe 95% ethanol extracts of aerial parts of three oleaceous plants were examined for their cytotoxicity against HepG-2, MCF-7, and THP-1 cell lines using MTT assay and doxorubicin (positive control). J. humile was bio-selected and submitted to bio-guided fractionation. Chromatographic workup of ethyl acetate and n-butanol fractions afforded two new compounds; 1-methoxyjasmigenin (1) and 1-methyl-9-aldojasmigenin (2), along with five known ones (3–7). Structures were unambiguously elucidated using 1D/2D NMR and ESI-HRMS. Isolated compounds were assessed for their anti-proliferative potential, and both selectivity index and statistical significance were determined. Molecular docking was conducted against the Mcl-1 receptor using (AZD5991) as a standard.ResultsJasmoside (5) was the most potent anticancer compound showing IC50 values of 66.47, 41.32, and 27.59 µg/mL against HepG-2, MCF-7, and THP-1 cell lines, respectively. Moreover, isojasminin (4) exhibited IC50 values of 33.49, 43.12, and 51.07 µg/mL against the same cell lines, respectively. Interestingly, 5 exhibited the highest selectivity index towards MCF-7 and THP-1, even greater than doxorubicin. Molecular docking results were in full agreement with the MTT assay and the proposed SAR.ConclusionIn this study, two new compounds were purified. The biological activity highlighted jasmoside (5) as a lead anticancer drug for further future investigation.  相似文献   

10.
Supercritical CO(2) fluid extraction (SFE-CO(2)) was used to extract volatiles from Patrinia Villosa Juss. An orthogonal test L(9) (3)(4) including pressure, temperature, dynamic extraction time and modifier was performed to get the optimal conditions. Extract 1 was obtained by the optimal extraction condition 1: pressure=35 MPa, T=45 degrees C, dynamic extraction time=2.0 h and V(modifier (MeOH))=0% as guided by the index 1: the free radical scavenging activities in vitro against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethyl-benzthiazoline-6-sulfonic acid) diammonium salt (ABTS). Extract 2 obtained by the optimal extraction condition 2: pressure=25 MPa, T=55 degrees C, dynamic time=2.5h and V(modifier (MeOH))=20% was guided by the index 2: the yield of the volatiles. The results showed that extract 1 possessed stronger antioxidant activity (EC(50)=32.01 microg/ml to DPPH and 50.90 microg/ml to ABTS(+)) than the extract 2 (EC(50)=95.62 microg/ml to DPPH and 99.78 microg/ml to ABTS(+)). Subsequently, the chemical compositions of the two extracts were identified by gas chromatography-mass spectrometry. Forty-six compounds were identified from extract 1, and the total volatile consisted of hydrocarbon (49.65%), aldehyde (16.66%), fatty acid (22.38%), terpene (9.04%) and little alcoholic. From extract 2, 32 compounds were identified, in which hydrocarbon, aldehyde, fatty acid and terpene possessed 58.21%, 5.97%, 13.19% and 21.79%, respectively. This is the first report of using SFE to extract the volatiles from P. Villosa Juss (a wild vegetable and medicine plant) and first time to systematically evaluate the volatiles' antioxidant activity and chemical composition.  相似文献   

11.
Oxidative stress is involved in the pathogenesis of a wide spectrum of diseases, implicating that strategies directed at counterbalancing oxidative processes could have a role in clinical medicine. There is also an evidence that oxidative stress acts as a major determinant of apoptotic cell death. Many studies have reported favourable effects of antioxidant formulas on several parameters of the oxidant-antioxidant balance, but none of them has focused whether antioxidant formulas could modulate apoptosis. We investigated in 20 healthy individuals the effect of supplementation with a formula containing alpha-tocopherol, alpha-lipoic acid, coenzyme Q(10), carnitines, and selenomethionine, on plasma oxidant status and peroxide levels, erythrocyte antioxidant enzymes, lymphocyte apoptosis, and generation of ROS at the mitochondrial level. Control subjects received only carnitines or an incomplete formula with alpha-tocopherol, alpha-lipoic acid, coenzyme Q(10), and selenomethionine. Supplementation with the complete formula resulted in a significant increase in the plasma antioxidant status that was mirrored by a decrease in blood peroxide levels and a reduced generation of ROS at the mitochondrial level. This was associated with a significant decrease in the frequency of peripheral blood lymphocytes, with either CD4 or CD8 phenotype, undergoing apoptosis. Less consistent results were found when either incomplete formula was used. Our study suggests that supplementation with antioxidant formulas can modulate the process of apoptosis under in vivo conditions. The clinical potential of this strategy in the treatment of diseases with an elevated commitment to apoptosis should be explored.  相似文献   

12.
13.
In the present study, a polyphenolic byproduct from olive mill wastewater (OMWW) was used for making piglet feed with antioxidant activity. For examining the antioxidant capacity of the feed, 30 piglets of 20 d old were divided into two groups receiving basal or experimental feed for 30 d. Blood and tissue samples were drawn at days 2, 20, 35 and 50 post-birth. The tissues collected were brain, heart, kidney, liver, lung, quadriceps muscle, pancreas, spleen and stomach. The antioxidant effects of the experimental feed were assessed by measuring oxidative stress biomarkers in blood and tissues. The oxidative stress markers were total antioxidant capacity (TAC), glutathione (GSH), catalase activity (CAT), protein carbonyls (CARB) and thiobarbituric acid reactive species (TBARS). The results showed that piglets fed with diet supplemented with OMWW polyphenols had significantly increased antioxidant mechanisms in blood and the majority of the tested tissues as shown by increases in TAC, CAT and GSH compared to control group. Moreover, piglets fed with the experimental feed exhibited decreased oxidative stress-induced damage to lipids and proteins as shown by decreases in TBARS and CARB respectively. This is the first study in which OMWW polyphenols were used for making pig feed with antioxidant activity.  相似文献   

14.
Many tropical plants have interesting biological activities with potential therapeutic applications. Garcinia mangostana Linn. (GML) belongs to the family of Guttiferae and is named “the queen of fruits”. It is cultivated in the tropical rainforest of some Southeast Asian nations like Indonesia, Malaysia, Sri Lanka, Philippines, and Thailand. People in these countries have used the pericarp (peel, rind, hull or ripe) of GML as a traditional medicine for the treatment of abdominal pain, diarrhea, dysentery, infected wound, suppuration, and chronic ulcer.  相似文献   

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