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1.
Antioxidant activity, urinary tract protective activity, and cardioprotective anti‐platelet effects are among the bioactivities associated with dietary phenolics. These bioactivities were measured in vitro in fruit extracts from seven Vaccinium species and five non‐Vaccinium species to determine their relationship to total phenolic content and to anthocyanin and proanthocyanidin content. Berries belonging to the genus Vaccinium were particularly high in antioxidant activity and urinary tract protective anti‐adhesion activity, while anti‐platelet activity varied among species. There was a positive relationship between antioxidant activity (using the oxygen radical absorbing capacity (ORAC) assay) and both the total phenolic (R2 = 0.76) and anthocyanin content (R2 = 0.43) of the fruit, although there was no relationship between ORAC and proanthocyanidin content. There were no relationships between anti‐adhesion activity and total phenolic content, anthocyanin content, or proanthocyanidin content. Likewise, no relationships were observed between anti‐platelet activity and total phenolic content, anthocyanin content, or proanthocyanidin content. These results suggest that while antioxidant properties are characteristic of all fruit phenolics, in vitro anti‐adhesion and anti‐platelet bioactivities may be due to less abundant phenolic subgroups. Copyright © 2007 Crown in the right of Canada and Society of Chemical Industry  相似文献   

2.
The antioxidant activity (AA) of substances present in several plant species has been widely studied which reflects their fundamental role in the protection of skin tissue against the harmful action of reactive oxygen species. Given the importance of effective and long‐lasting protection against ultraviolet radiation, we studied the AA of several plant derivatives and extracts over time. Several chemical in vitro methods may be used to evaluate antioxidant capability, among which the 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) method stands out, despite its unspecificity, as the most cited and described method in the literature. In this work the AA was evaluated by measuring their capacity to reduce DPPH in 30 min, which is suggested in the literature, and additionally at different times up to 8 h from the baseline reading. The methodology used to evaluate the AA over time was validated. It is important to emphasize that this study proposes to modify the conventional DPPH method, although considered to be non‐specific, to be used to test new antioxidant agents. This represents a considerable advantage because some substances show no significant activity during the first 30 min of reaction. Among other plant products, we tested a proantocyanidin‐rich grapeseed extract, a hesperidin derivative, a rutin‐containing ginkgo extract, a polyphenol‐containing yerba maté extract and tocopheryl acetate, all of which were properly standardized. As they have different antioxidant profiles, each ingredient showed a specific behaviour over time, which may promote the selection of anti‐radical compounds capable of offering protection against external agents. Combining extracts and plant derivatives that present fast, medium and slow antioxidant kinetic it is possible to create complexes capable of offering an effective protection from the moment of application up to several hours later. It is a perfectly feasible method, and such combinations prove to be more effective and have more durable effect.  相似文献   

3.
Four proteins, α/β globulin, serum albumin, γ‐globulin and fibrinogen, were isolated from bovine blood and hydrolysed using papain. Hydrolysates were assessed for non‐cellular and cellular antioxidant activity. The anti‐proliferative activity of hydrolysed fractions was assessed in a number of cancer cell lines including U937 lymphoma cells, MCF‐7 breast cancer cells, HepG2 hepatocytes and Caco‐2 epithelial colorectal adenocarcinoma cells. Anti‐inflammatory activity of the hydrolysates was also assessed. Hydrolysates generated from γ‐globulin or fibrinogen had significant antioxidant activity in non‐cellular assays. Hydrolysates were also found to be highly toxic to different cancer cell lines, in particular U937 lymphoma cells when assessed using the MTT assay. The fibrinogen hydrolysate was the most toxic sample and toxicity appeared to correlate with its non‐cellular antioxidant activity. None of the hydrolysates had significant anti‐inflammatory activity. The high cytotoxicity of the γ‐globulin and the fibrinogen hydrolysates towards cancer cells may indicate a potential use as anti‐proliferative agents.  相似文献   

4.
5.
Green tea extract was encapsulated into liposomes to enhance bioavailability and stability of catechins by protecting their functional properties simultaneously. Encapsulation was achieved by dispersing 1% (w/v) soy lecithin through high pressure homogenization (microfluidization) and ultrasonication. Effects of homogenization type and pH of the dispersing medium on the physical properties and stability of the liposomes during 1‐mo storage period were investigated. Mean particle size, total phenolic content by Folin–Ciocalteu method and antioxidant activity by 2‐diphenyl‐1‐picrylhydrazyl radical scavenging and ferric reducing‐antioxidant power methods, and transmission electron microscopy (TEM) experiments were conducted for characterization. Green tea extract loaded liposomes prepared by microfluidization in distilled water were determined as the most stable system which demostrated no significant difference (P > 0.05) on mean particle size, total phenolic content, and antioxidant activity between the first and final day of 1‐mo storage time. Additionally, uniform size and shape in TEM images supported the results.  相似文献   

6.
The antioxidative and anti‐allergic activities of fresh and aged black garlic extracts were investigated. The garlic samples were extracted with 70% ethanol (v/v) and the total phenolic content was measured. The antioxidant capacity of extracts was assessed by determining the scavenging activities on 1,1‐diphenyl‐2‐picrylhydrazyl and hydroxyl radicals, ferricyanide reducing power, ferrous ion‐chelating ability and inhibitory effect on linoleic acid peroxidation. The anti‐allergic activity of extracts was analysed by measuring their inhibitory effects against β‐hexosaminidase release. The aged black garlic exhibited significantly higher phenolic content and greater antioxidative activity than fresh garlic. Both garlic extracts showed strong antioxidant capacity in a dose‐dependent manner. On the other hand, a considerably higher suppression of β‐hexosaminidase release was found in fresh garlic extract at lower concentration compared with that of the black garlic. Results of this study illustrate that ageing of garlic could enhance its antioxidant capacity, but could decrease its anti‐allergic activity.  相似文献   

7.
为制备模拟细胞外基质结构的微纳尺度复合材料,利用静电纺丝技术制备了聚己内酯(Polycaprolactone,PCL)微米纤维膜,通过与纳米尺度的细菌纤维素(Bacterial Cellulose,BC)原位复合,制备了BC/PCL复合纤维支架。采用扫描电镜、红外光谱分析、X射线衍射分析对材料的形貌、结构进行了表征。通过单轴力学测试对复合材料力学性能进行了研究,并利用成纤维细胞对复合材料的生物相容性进行评价。结果表明:通过静电纺丝法制备的PCL微米纤维的平均直径,随聚合物纺丝液质量分数的增加有增加的趋势,BC与PCL微米纤维复合后,BC纳米纤维渗透入微米纤维膜内部,实现微纳米纤维较好的复合。红外光谱分析和X射线衍射分析进一步证明BC和PCL微米纤维成功复合。PCL微米纤维膜复合BC膜后,相比PCL微米纤维膜增加了其断裂强度,同时复合支架无明显细胞毒性,可应用于生物医学领域。  相似文献   

8.
The aim of this research was to study the encapsulation of eugenol as a volatile active substance by inclusion with β-cyclodextrin (β-CD) and 2-hydroxypropyl-β-cyclodextrin (2-HP-β-CD), and by an emulsion–diffusion method with polycaprolactone (PCL). After formulation of each type of complex, size, zeta-potential, and thermal properties were determined by using Nanosizer®, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM). Overall, the mean sizes of encapsulated eugenol were the same at 320 nm. However, the size distribution of the β-CD and 2-HP-β-CD inclusion complex was poly-disperse as compared with eugenol encapsulated with polycaprolactone (PCL). TGA analysis revealed the encapsulation efficiency of PCL, β-CD eugenol and 2-HP-β-CD eugenol inclusion complexes were 100%, 90.9% and 89.1%, respectively. The study of oxidation stability revealed the emulsion–diffusion method was more efficient than the molecular inclusion method resulting from high stability depending on storage time. On the other hand, β-CD was more effective than 2-HP-β-CD for eugenol encapsulation. It is supposed that the side chain of hydroxypropyl group of 2-HP-β-CD might interrupt eugenol inclusion within the cavity of 2-HP-β-CD molecule. From our experiments, we concluded that the emulsion–diffusion method was the most effective for eugenol encapsulation to protect from light oxidation during storage time due to their complete wrapping of eugenol by PCL layer from TEM analysis.  相似文献   

9.
It is well‐known that zinc ions are widely used in cosmetic products. Their popularity is associated with the multifunctional profile of Zn2+, which is classified as an essential chemical element in the human body. This review examines numerous beneficial biological properties of zinc‐containing compounds and classifies the compounds used in cosmetic products according to their functionality profile: antioxidant, sunscreen, anti‐inflammatory, anti‐pigmentation, anti‐ageing, anti‐acne, antimicrobial, anti‐odour, cleansing or stabilizing activity. It also underlines the significance of zinc in enzymatic processes, which depends on the enzyme type acts as inhibitor or enzymatic stimulator. Moreover, the article describes the chemical nature of the most interesting groups of Zn compounds.  相似文献   

10.
α‐Amylase and α‐glucosidase have been targeted as potential avenues for modulation of postprandial hyperglycemia through mild inhibition of the enzymatic breakdown of complex carbohydrates to decrease meal‐derived glucose absorption. Water‐soluble extracts with optimized phenolic content of selected American and Asian foods were investigated for inhibitory activity against α‐amylase and α‐glucosidase, as well as angiotensin I‐converting enzyme (ACE), which has been linked to hyperglycemia‐associated hypertension. Porcine pancreatic α‐amylase (PPA) was allowed to react with each phenolic‐optimized food extract, and the derivatized enzyme–phytochemical mixtures obtained were characterized for residual amylase activity. The α‐glucosidase and ACE activities were determined in the presence of each phenolic‐optimized food extract. The amylase activity was inhibited more than the glucosidase activity in the presence of these phytochemical extracts, and more so by Asian foods than by American foods. The Asian spice ginger was found to possess strong ACE inhibitory activity in addition to significant anti‐amylase activity. The α‐amylase enzyme inhibition was positively associated with extract antioxidant activity and negatively with extract protein content. The significance of food‐grade, plant‐based amylase inhibitors for modulation of carbohydrate breakdown and control of glycemic index of foods in the context of preventing hyperglycemia and diabetes mellitus complications in the long term and ACE inhibitors for modulation of associated hypertension is hypothesized and discussed.  相似文献   

11.
Biological and therapeutic properties of bee pollen: a review   总被引:1,自引:0,他引:1       下载免费PDF全文
Natural products, including bee products, are particularly appreciated by consumers and are used for therapeutic purposes as alternative drugs. However, it is not known whether treatments with bee products are safe and how to minimise the health risks of such products. Among others, bee pollen is a natural honeybee product promoted as a valuable source of nourishing substances and energy. The health‐enhancing value of bee pollen is expected due to the wide range of secondary plant metabolites (tocopherol, niacin, thiamine, biotin and folic acid, polyphenols, carotenoid pigments, phytosterols), besides enzymes and co‐enzymes, contained in bee pollen. The promising reports on the antioxidant, anti‐inflammatory, anticariogenic antibacterial, antifungicidal, hepatoprotective, anti‐atherosclerotic, immune enhancing potential require long‐term and large cohort clinical studies. The main difficulty in the application of bee pollen in modern phytomedicine is related to the wide species‐specific variation in its composition. Therefore, the variations may differently contribute to bee‐pollen properties and biological activity and thus in therapeutic effects. In principle, we can unequivocally recommend bee pollen as a valuable dietary supplement. Although the bee‐pollen components have potential bioactive and therapeutic properties, extensive research is required before bee pollen can be used in therapy. © 2016 Society of Chemical Industry  相似文献   

12.
PCL with biodegradable property and Spirulina with various biological activities offer good alternative ingredients for the fabrication of functional nanofibers in tissue engineering. The aim of the study is to obtain PCL/Spirulina nanofibers with low diameters and to determine their wettability, antioxidant activity, and phycocyanin release to evaluate their potential as bioactive scaffolds in different applications. PCL/acetic acid/pyridine solutions with three different Spirulina concentrations were electrospun and the obtained nanofibers were investigated. The thinnest PCL/Spirulina nanofibers (117.20 nm) were obtained at 1.5% Spirulina concentration. Although PCL nanofibers with 6% Spirulina concentration showed the highest antioxidant activity and amount of phycocyanin released, PCL nanofibers with 3% Spirulina concentration having similar in vitro results showed superiority when considering the diameter and uniformity of the nanofibers and the cost of the material. The PCL/Spirulina nanofibers with small diameters and antioxidant activity could be regarded as potential extracellular matrix material for tissue engineering.  相似文献   

13.
为研究纤维基载药介孔SiO2纳米粒子的释药性能,采用溶胶-凝胶法制备介孔SiO2,并采用静电纺丝技术制备了负载介孔SiO2的聚己内酯(PCL)纤维膜,在介孔SiO2纳米粒子中装载抗菌药物盐酸环丙沙星,于酸性条件下分别探讨了盐酸环丙沙星在纳米粒子和复合纤维膜中的释放性能及释放机制,并对2种药物释放模型进行动力学研究。结果表明:介孔SiO2纳米粒子的成型受pH值影响较大,在可成型范围内,随着pH值的增大,纳米粒子的粒径逐渐增大;随着介孔SiO2比例的增加,PCL复合纤维的细度逐渐下降;盐酸环丙沙星在单独纳米粒子和复合纤维膜中的释放都具有初始释放速率大,后期释放缓慢的特点,12 h内在2种载体中的累积释放率分别可达到55.51%和16.53%;扩散是药物在2种载体中释放的主要机制。  相似文献   

14.
BACKGROUND: Increasing evidence supports the potential health benefits of herbal extracts displaying antioxidant, anti‐inflammatory and antitumour activities. Environment can have a pronounced effect on phenolic content and antioxidant capacity. The objectives of this study were to evaluate the total phenolic contents and antioxidant capacities of five different herbs grown under greenhouse and field conditions and to assess their potential anti‐inflammatory effects. RESULTS: High total polyphenolic (TPP) content (measured by the Folin‐Ciocalteu reagent method) and high Trolox equivalent antioxidant capacity (TEAC) were observed in all herbs evaluated. Leaves from thyme, sage, spearmint and peppermint grown in the greenhouse showed significantly higher TPP content and TEAC than those grown under field conditions, with a threefold difference being observed in peppermint. Rosemary, spearmint and peppermint extracts showed stronger inhibition of cyclooxygenase COX‐2 than of COX‐1. CONCLUSION: The results show that producing herbs under greenhouse conditions can improve their biological activities by increasing TPP contents and antioxidant capacities. The selective inhibition of COX‐2 activity by rosemary, spearmint and peppermint suggests that they may be useful as anti‐inflammatory agents with fewer side effects than regular non‐steroidal drugs. Copyright © 2010 Society of Chemical Industry  相似文献   

15.
BACKGROUND: Licorice root is one of the most widely used medicinal herbs and its medicinal properties, such as antibacterial, anti‐ulcer, anti‐tumorigenic and anti‐atherosclerotic activities, have been widely reported. However, there are only a few reports on basic chemical and biological studies of the water distilled components of licorice root. RESULTS: Chinese licorice root was water distilled and the distillate was subsequently extracted with dichloromethane. Residual aqueous solution from the extraction was fractionated using column chromatography. A total of 127 chemicals were identified in the dichloromethane extract, which inhibited hexanal oxidation by over 90% for 45 days at the level of 50 µg mL?1. A fraction eluted from the residual aqueous solution with acetone exhibited potent antioxidant activities both in a thiobarbituric acid assay and in a malonaldehyde/gas chromatography assay. The acetone fraction also exhibited strong anti‐inflammatory activity (77.9% inhibition at the level of 62 µg mL?1) in a lipoxygenenase inhibitor screening anti‐inflammatory assay. CONCLUSION: This study demonstrated the antioxidant and anti‐inflammatory activities of the water distillate obtained from Chinese licorice root. Some volatile chemicals among the many components identified in the water distillate exhibited antioxidant activity, suggesting that many medicinal compounds escape with water vapor into the ambient air during the preparation of herbal medicine. Copyright © 2008 Society of Chemical Industry  相似文献   

16.
Antioxidant and antibacterial activity of a methanol rosemary extract (RE) containing 30% carnosic acid (CA), 16% carnosol (COH) and 5% rosmarinic acid (RA) was studied in vitro alone and in combination with the antioxidant food additives butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA). The antioxidant efficiency of the extract, CA, and RA, was determined by a kinetic analysis of the 2,2-diphenyl-2-picrylhydrazyl hydrate radical (DPPH·) scavenging activity. RE showed two different rate slopes in the reduction of DPPH· vs. time curve, which correlated with the distinct behaviours of RA and CA; pure RA reached the plateau more rapidly than CA. A synergistic antioxidant effect between RE and BHT was demonstrated by isobolographic analysis and a synergistic interaction of RE with BHA to inhibit Escherichia coli and Staphylococcus aureus growth was observed. Therefore, rosemary not only enhances the antioxidant efficiency of BHA and BHT, but also the antibacterial effect of BHA; allowing a decrease from 4.4 to17 folds in the amounts of the synthetic compounds used.  相似文献   

17.
BACKGROUND: Consumer demand for products rich in phytochemicals is increasing as a result of greater awareness of their potential health benefits. However, processed products are stored for long‐term and the phytochemicals are susceptible to degradation during storage. The objective of this study was to assess the storage effects on phytochemicals in thermally processed blueberries. Thermally processed canned berries and juice/puree were analysed for phytochemicals during their long‐term storage. RESULTS: The phytochemical retention of thermally processed blueberries during storage was not influenced by production system (conventional versus organic). During 13 months of storage, total anthocyanins, total phenolics and total antioxidant activity in canned blueberry solids decreased by up to 86, 69 and 52% respectively. In canned blueberry syrup, total anthocyanins and total antioxidant activity decreased by up to 68 and 15% respectively, while total phenolic content increased by up to 117%. Similar trends in phytochemical content were observed in juice/puree stored for 4 months. The extent of changes in phytochemicals of thermally processed blueberries during storage was significantly influenced by blanching. CONCLUSION: Long‐term storage of thermally processed blueberries had varying degrees of influence on degradation of total anthocyanins, total phenolics and total antioxidant activity. Blanching before thermal processing helped to preserve the phytochemicals during storage of blueberries. Copyright © 2011 Society of Chemical Industry  相似文献   

18.
The fruits of various Zanthoxylum species are used as a spice in the Chinese and Japanese cuisine because of their delicate flavour and tingling properties. The lipophilic hydroxyalkamides hydroxy α‐ and β‐sanshools ( 1a,b ) have been identified as the tingling principles of these plants, and previous studies have validated a sanshool‐rich lipophilic extract from the fruit husks of Z. bungeanum Maxim. (Zanthalene®) as an anti‐itching cosmetic ingredient. Because tingling is a sort of ‘paralytic pungency’, and Zanthalene® potently inhibits synaptic transmission, we have investigated its capacity to relax subcutaneous muscles and act as a topical lifting agent for wrinkles. An anti‐wrinkles extract rich in spilanthol ( 2 ), a lipophilic alkamide having sensory properties similar to those of Zanthalene®, was used as a reference. Short‐term (lifting effect) and long‐term (anti‐wrinkle) improvements of skin roughness parameters were evaluated by both objectives’ and subjectives’ measurements. An immediate ‘lifting’ effect was observed with the sanshool‐rich lipophilic extract, at dosages at which the reference alkamide extract was inactive in the objective assays. Limited desensitization after repeated application and good overall tolerability were observed, although a modest long‐term anti‐wrinkle effect was shown by both products. Taken together, these observations validate the use of sanshool‐rich lipophilic extracts as an efficacious, immediate‐action lifting agent, and exemplify the relevance of sensory observations to foster the development of innovative cosmetic ingredients.  相似文献   

19.
Abstract

Rosmarinic acid is a natural antioxidant and is found as a secondary metabolite in rosemary (Rosmarinus officinalis). It is of interest in food preservation due to its antioxidant and antimicrobial activities. Previously maintained shoot‐based clonal line of rosemary designated as R‐l (based on RA content, total phenolics content, tolerance to Pseudomonas sp and RA stimulation) was used in this study to compare RA biosynthesis in shoot vs callus cultures. Callus cultures were generated from shoot cultures of R‐l line following transformation with Agrobacterium rhizogenes‐containing a natural plasmid that alters plant development. The shoot and transformed callus cultures of R‐l were isolated and maintained separately on hormone free Murashige and Skoog medium (MS/HF). The effect of light and dark conditions on callus growth and RA production was investigated. RA biosynthesis in shoot cultures was also compared due to its relevance to greenhouse production and organ culture. We found that callus maintained in light grows more rapidly when compared to shoot grown in light and callus grown in dark. The ratio of biomass accumulated by callus (Light): callus (Dark): Shoot was 4:1:1 based on fresh weight and 4:1:2 based on dry weight. The ratio of peak RA levels (expressed mg/g DW) was 1:1:10. RA production in callus was small compared to shoot and light had no effect on peak RA level in the callus system, but it effected the growth rate significantly.  相似文献   

20.
ABSTRACT: Honey, propolis, and royal jelly, products originating in the beehive, are attractive ingredients for healthy foods. Honey has been used since ancient times as part of traditional medicine. Several aspects of this use indicate that it also has functions such as antibacterial, antioxidant, antitumor, anti‐inflamatory, antibrowning, and antiviral. Propolis is a resinous substance produced by honeybees. This substance has been used in folk medicine since ancient times, due to its many biological properties to possess, such as antitumor, antioxidant, antimicrobial, anti‐inflammatory, and immunomodulatory effects, among others. Royal jelly has been demonstrated to possess numerous functional properties such as antibacterial activity, anti‐inflammatory activity, vasodilative and hypotensive activities, disinfectant action, antioxidant activity, antihypercholesterolemic activity, and antitumor activity. Biological activities of honey, propolis, and royal jelly are mainly attributed to the phenolic compounds such as flavonoids. Flavonoids have been reported to exhibit a wide range of biological activities, including antibacterial, antiviral, anti‐inflammatory, antiallergic, and vasodilatory actions. In addition, flavonoids inhibit lipid peroxidation, platelet aggregation, capillary permeability and fragility, and the activity of enzyme systems including cyclo‐oxygenase and lipoxygenase.  相似文献   

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