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1.
The medicinal plants of Huang-qi (Radix Astragali) and Sheng-ma (Cimicifuga foetida) demonstrate significantly better antioxidant effects when used in combination than when used alone. However, the bioactive components and interactional mechanism underlying this synergistic action are still not well understood. In the present study, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay was employed to investigate the antioxidant capacity of single herbs and their combination with the purpose of screening synergistic antioxidant compounds from them. Chromatographic isolation was performed on silica gel, Sephadex LH-20 columns and HPLC, and consequently to yield formononetin, calycosin, ferulic acid and isoferulic acid, which were identified by their retention time, UV λmax, MS and MS/MS data. The combination of isoferulic acid and calycosin at a dose ratio of 1∶1 resulted in significant synergy in scavenging DPPH radicals and ferric reducing antioxidant power (FRAP) assay. Furthermore, the protective effects of these four potential synergistic compounds were examined using H2O2-induced HepG2 Cells bioassay. Results revealed that the similar synergy was observed in the combination of isoferulic acid and calycosin. These findings might provide some theoretical basis for the purported synergistic efficiency of Huang-qi and Sheng-ma as functional foods, dietary supplements and medicinal drugs. 相似文献
2.
Recently we described the pH dependence of activity for a family of cationic antimicrobial peptides (CAMPs) selected from a combinatorial library. In the current work we report on the effects of toxic ions (Cu2+, Zn2+, and F−) and the chelator EDTA on the activity profiles of one member of this family, the 12-residue cationic antimicrobial peptide *ARVA, against a panel of microorganisms. All four ions exhibited either synergy or additivity with *ARVA for all organisms tested with the exception of *ARVA combined with NaF against Candida albicans which exhibited indifference. CuCl2 and ZnCl2 exhibited synergy with *ARVA against both the Gram negative Pseudomonas aeruginosa and the Gram positive Staphylococcus aureus as well as strong additivity against Escherichia coli at submillimolar concentrations. The chelator EDTA was synergistic with *ARVA against the two Gram negative organisms but showed only simple additivity with S. aureus and C. albicans despite their much lower MICs with EDTA. This effect may be related to the known differences in the divalent ion binding properties of the Gram negative LPS layer as compared to the peptidoglycan layer of the Gram positive organism. Unlike the other ions, NaF showed only additivity or indifference when combined with *ARVA and required much higher concentrations for activity. The yeast C. albicans did not show synergy or strong additivity with any of the inhibitory compounds tested. The effects of toxic ions and chelators observed here have important implications for applications using CAMPs and for the design of novel formulations involving CAMPs. This article is part of a Special Issue entitled: Interfacially Active Peptides and Proteins. Guest Editors: William C. Wimley and Kalina Hristova. 相似文献
3.
Heitaroh Iwata Toshio Matsuda Sadaaki Maeda Akemichi Baba 《Biochimica et Biophysica Acta (BBA)/General Subjects》1979,583(2):159-166
The effect of ascorbic acid on microsomal thiamine diphosphate activity in rat brain was examined. Ascorbic acid at 0.02–0.1 mM increased the thiamine diphosphate activity by 20–600% and produced a significant amount of lipid peroxide, which was measured with thiobarbiturate under the same conditions as the enzyme. A lag period of about 10 min was observed in the process of stimulation of enzyme activity by ascorbic acid. The stimulation of enzyme activity and the lipid peroxidation induced by ascorbic acid were blocked by metal-binding compounds (EDTA, α,α′-dipyridyl, o-phenanthroline) and an antioxidant (N,N′-diphenyl p-phenylenediamine). GSH significantly enhanced the stimulation of enzyme activity and formation of lipid peroxide by 0.02–0.05 mM ascorbic acid. The effect of GSH was due in part to maintenance of the concentration of ascorbic acid in the medium, since GSH could convert dehydroascorbic acid, an oxidized form of ascorbic acid, to ascorbic acid. 相似文献
4.
Lactic Acid Permeabilizes Gram-Negative Bacteria by Disrupting the Outer Membrane 总被引:8,自引:4,他引:8
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H.-L. Alakomi E. Skytt M. Saarela T. Mattila-Sandholm K. Latva-Kala I. M. Helander 《Applied microbiology》2000,66(5):2001-2005
The effect of lactic acid on the outer membrane permeability of Escherichia coli O157:H7, Pseudomonas aeruginosa, and Salmonella enterica serovar Typhimurium was studied utilizing a fluorescent-probe uptake assay and sensitization to bacteriolysis. For control purposes, similar assays were performed with EDTA (a permeabilizer acting by chelation) and with hydrochloric acid, the latter at pH values corresponding to those yielded by lactic acid, and also in the presence of KCN. Already 5 mM (pH 4.0) lactic acid caused prominent permeabilization in each species, the effect in the fluorescence assay being stronger than that of EDTA or HCl. Similar results were obtained in the presence of KCN, except for P. aeruginosa, for which an increase in the effect of HCl was observed in the presence of KCN. The permeabilization by lactic and hydrochloric acid was partly abolished by MgCl2. Lactic acid sensitized E. coli and serovar Typhimurium to the lytic action of sodium dodecyl sulfate (SDS) more efficiently than did HCl, whereas both acids sensitized P. aeruginosa to SDS and to Triton X-100. P. aeruginosa was effectively sensitized to lysozyme by lactic acid and by HCl. Considerable proportions of lipopolysaccharide were liberated from serovar Typhimurium by these acids; analysis of liberated material by electrophoresis and by fatty acid analysis showed that lactic acid was more active than EDTA or HCl in liberating lipopolysaccharide from the outer membrane. Thus, lactic acid, in addition to its antimicrobial property due to the lowering of the pH, also functions as a permeabilizer of the gram-negative bacterial outer membrane and may act as a potentiator of the effects of other antimicrobial substances. 相似文献
5.
Y. Markovska M. Geneva P. Petrov M. Boychinova I. Lazarova I. Todorov I. Stancheva 《Russian Journal of Plant Physiology》2013,60(5):623-632
The effects of EDTA application to heavy metal-polluted soil on phytoextraction of heavy metals, leaf anatomy, gas exchange parameters, enzyme activities of C4 carbon cycle, antioxidant defense, and active compounds of Tribulus terrestris L. were evaluated. The addition of EDTA to the soil polluted with Cd and Pb markedly increased dry weight and Pb, Zn, and Cd contents in shoots. Plants responded to the action of EDTA by an increased stomatal conductance, photosynthetic and transpiration rates, water use efficiency, chlorophyll and carotenoid contents. The activities of C4 carbon cycle enzymes simultaneously increased, thus concentrating CO2 for enhanced CO2 assimilation and providing NADPH for the antioxidant system. Antioxidants, such as ascorbate, reduced glutathione, and flavonoids, increased more in the shoots of T. terrestris after the addition of EDTA. The activities of guaiacol peroxidase, catalase, and the enzymes of the ascorbate-glutathione cycle enhanced significantly in the presence of EDTA. Increased activities of antioxidant enzymes suggest that they have some additive functions in the mechanism of metal tolerance. EDTA application lowered the activity of phenylalanine ammonia-lyase and the content of total phenols, MDA, hydrogen peroxide, dehydroascorbate, and lipid-soluble antioxidant capacity expressed as α-tocopherol. Increased levels of total radical-scavenging activity are in correspondence with the activity of water-soluble antioxidant compounds in T. terrestris tissues. The content of furostanol saponins protodioscin, prototribestin, and rutin increased as a result of EDTA addition. The results obtained allowed us to assume that applied EDTA reduced a negative heavy metal impact on puncture vine photosynthesis and antioxidant potential. 相似文献
6.
F Bruzzese B Pucci M R Milone C Ciardiello R Franco M I Chianese M Rocco E Di Gennaro A Leone A Luciano C Arra D Santini M Caraglia A Budillon 《Cell death & disease》2013,4(10):e878
Patients with advanced prostate cancer (PCa) and multiple myeloma (MM) have limited long-term responses to available therapies. The histone deacetylase inhibitor panobinostat has shown significant preclinical and clinical anticancer activity in both hematological and solid malignancies and is currently in phase III trials for relapsed MM. Bisphosphonates (BPs), such as zoledronic acid (ZOL), inhibit osteoclast-mediated bone resorption and are indicated for the treatment of bone metastasis. BPs, including ZOL, have also shown anticancer activity in several preclinical and clinical studies. In the present report, we found a potent synergistic antiproliferative effect of panobinostat/ZOL treatment in three PCa and three MM cell lines as well as in a PCa ZOL-resistant subline, independently of p53/KRAS status, androgen dependency, or the schedule of administration. The synergistic effect was also observed in an anchorage-independent agar assay in both ZOL-sensitive and ZOL-resistant cells and was confirmed in vivo in a PCa xenograft model. The co-administration of the antioxidant N-acetyl-L-cysteine blocked the increased reactive oxygen species generation and apoptosis observed in the combination setting compared with control or single-agent treatments, suggesting that oxidative injury plays a functional role in the synergism. Proapoptotic synergy was also partially antagonized by the addition of geranyl-geraniol, which bypasses the inhibition of farnesylpyrophosphate synthase by ZOL in the mevalonate pathway, supporting the involvement of this pathway in the synergy. Finally, at the molecular level, the inhibition of basal and ZOL-induced activation of p38-MAPK by panobinostat in sensitive and ZOL-resistant cells and in tumor xenografts could explain, at least in part, the observed synergism. 相似文献
7.
Thiago C. Genaro-Mattos ?ngelo Q. Maurício Daniel Rettori Antonio Alonso Marcelo Hermes-Lima 《PloS one》2015,10(6)
Caffeic acid (CA) is a phenolic compound widely found in coffee beans with known beneficial effects in vivo. Many studies showed that CA has anti-inflammatory, anti-mutagenic, antibacterial and anti-carcinogenic properties, which could be linked to its antioxidant activity. Taking in consideration the reported in vitro antioxidant mechanism of other polyphenols, our working hypothesis was that the CA antioxidant activity could be related to its metal-chelating property. With that in mind, we sought to investigate the chemical antioxidant mechanism of CA against in vitro iron-induced oxidative damage under different assay conditions. CA was able to prevent hydroxyl radical formation promoted by the classical Fenton reaction, as determined by 2-deoxyribose (2-DR) oxidative degradation and DMPO hydroxylation. In addition to its ability to prevent hydroxyl radical formation, CA had a great inhibition of membrane lipid peroxidation. In the lipid peroxidation assays CA acted as both metal-chelator and as hydrogen donor, preventing the deleterious action promoted by lipid-derived peroxyl and alkoxyl radicals. Our results indicate that the observed antioxidant effects were mostly due to the formation of iron-CA complexes, which are able to prevent 2-DR oxidation and DMPO hydroxylation. Noteworthy, the formation of iron-CA complexes and prevention of oxidative damage was directly related to the pH of the medium, showing better antioxidant activity at higher pH values. Moreover, in the presence of lipid membranes the antioxidant potency of CA was much higher, indicating its enhanced effectiveness in a hydrophobic environment. Overall, our results show that CA acts as an antioxidant through an iron chelating mechanism, preventing the formation of free hydroxyl radicals and, therefore, inhibiting Fenton-induced oxidative damage. The chemical properties of CA described here—in association with its reported signaling effects—could be an explanation to its beneficial effects observed in vivo. 相似文献
8.
Abraham A Paul Omolaja R Osoniyi Queensley A Eghianruwa Olayemi G Oparinde Adetunji S Adesina 《International Journal of Biochemistry and Molecular Biology》2021,12(1):8
The multifunctional nature of antioxidant peptides makes them more attractive candidates as dietary ingredients in health maintenance. Therefore, food protein-derived antioxidant peptides are continuously investigated. This study investigated the in vitro antioxidant properties of hydrolysate and ultrafiltered peptide fractions of Pachymelania aurita and Tympanatonus fuscatus var radula-two commonly consumed marine molluscs known as periwinkles in southern Nigeria. Simulated gastrointestinal digestion (SGID) of soluble proteins of T. fuscatus and P. aurita was carried out using pepsin, trypsin and chymotrypsin, and the SGID hydrolysates were fractionated using a 3 kDa membrane filter. The hydrolysates and their fractions were investigated for anti-lipid peroxidation, hydroxyl radical scavenging activity (HRSA), ferric reducing antioxidant property (FRAP) and metal chelation activity, and they demonstrated clear antioxidant properties in all the assay models used. Low molecular weight fractions of the hydrolysates demonstrated more potent antioxidant activity than higher molecular weight fractions. This is profound in the metal chelation assay, where low molecular weight peptide fractions, T ≤ 3 kDa and P ≤ 3 kDa (IC50 values of 8.10 ± 0.011 and 5.56 ± 0.50 µg/ml respectively) had activity that is similar to that of EDTA (11.84 ± 0.89 µg/ml). Similar activity effects were observed in other assays where there was about 3-fold higher activity in low molecular weight fractions. These results demonstrate the presence of antioxidant peptide(s) in the protein hydrolysates of the periwinkles. 相似文献
9.
Pasquale Filannino Ivana Cavoski Nadia Thlien Olimpia Vincentini Maria De Angelis Marco Silano Marco Gobbetti Raffaella Di Cagno 《PloS one》2016,11(3)
Cactus pear (Opuntia ficus-indica L.) is widely distributed in the arid and semi-arid regions throughout the world. In the last decades, the interest towards vegetative crop increased, and cladodes are exploited for nutraceutical and health-promoting properties. This study aimed at investigating the capacity of selected lactic acid bacteria to increase the antioxidant and anti-inflammatory properties of cactus cladodes pulp, with the perspective of producing a functional ingredient, dietary supplement or pharmaceutical preparation. Preliminarily, the antioxidant activity was determined through in vitro assays. Further, it was confirmed through ex vivo analysis on intestinal Caco-2/TC7 cells, and the profile of flavonoids was characterized. Cactus cladode pulp was fermented with lactic acid bacteria, which were previously selected from plant materials. Chemically acidified suspension, without bacterial inoculum and incubated under the same conditions, was used as the control. Lactobacillus plantarum CIL6, POM1 and 1MR20, Lactobacillus brevis POM2 and POM4, Lactobacillus rossiae 2LC8 and Pediococcus pentosaceus CILSWE5 were the best growing strains. Fermentation of cladode pulp with L. brevis POM2 and POM4 allowed the highest concentration of γ-amino butyric acid. Lactic acid fermentation had preservative effects (P<0.05) on the levels of vitamin C and carotenoids. Two flavonoid derivatives (kaemferol and isorhamnetin) were identified in the ethyl acetate extracts, which were considered to be the major compounds responsible for the increased radical scavenging activity. After inducing oxidative stress by IL-1β, the increased antioxidant activity (P<0.05) of fermented cladode pulp was confirmed using Caco-2/TC7 cells. Fermented cladode pulp had also immune-modulatory effects towards Caco-2 cells. Compared to the control, fermented cladode pulp exhibited a significantly (P<0.05) higher inhibition of IL-8, TNFα and prostaglandins PGE2 synthesis. The highest functional effect was found using ethyl acetate extracts. In conclusion, fermentation, especially with L. plantarum strains and L. brevis POM4, enhanced the antioxidant and immune-modulation features of cladode pulp. 相似文献
10.
The phytochemical content, antioxidant activity and antiproliferative properties of three diverse varieties of proso millet are reported. The free phenolic content ranged from 27.48 (Gumi 20) to 151.14 (Mi2504-6) mg gallic acid equiv/100 g DW. The bound phenolic content ranged from 55.95 (Gumi20) to 305.81 (Mi2504-6) mg gallic acid equiv/100 g DW. The percentage contribution of bound phenolic to the total phenolic content of genotype samples analyzed ranged between 62.08% and 67.05%. Ferulic acid and chlorogenic acid are the predominant phenolic acid found in bound fraction. Caffeic acid and p-coumaric acid were also detected. Syringic acid was detected only in the free fraction. The antioxidant activity was assessed using the hydrophilic peroxyl radical scavenging capacity (PSC) assay. The PSC antioxidant activity of the free fraction ranged from 57.68 (Mi2504-6) to 147.32 (Gumi20) µmol of vitamin C equiv/100 g DW. The PSC antioxidant activity of the bound fraction ranged from 95.38 (Mizao 52) to 136.48 (Gumi 20) µmol of vitamin C equiv/100 g DW. The cellular antioxidant activity (CAA) of the extract was assessed using the HepG2 model. CAA value ranged from 2.51 to 6.10 µmol equiv quercetin/100 g DW. Antiproliferative activities were also studied in vitro against MDA human breast cancer and HepG2 human liver cancer cells. Results exhibited a differential and possible selective antiproliferative property of the proso millet. These results may be used to direct the consumption of proso millet with improved health properties. 相似文献
11.
Yon-Suk Kim Jin-Woo Hwang Seo-Hee Kang Hye-Ran Kim Jae-Young Je Ee-Hwa Kim You-Jin Jeon Sang-Ho Moon Byong-Tae Jeon Pyo-Jam Park 《Biotechnology and Bioprocess Engineering》2013,18(4):819-826
This study evaluated the antioxidant potential of extracts from Cornus walteri W. (CW) using various assays for natural antioxidants. We determined the polyphenol and flavonoid contents, as well as the antioxidant properties of water and ethanol extracts from the CW compared with those of other natural and synthetic antioxidants. CW extracts had high total phenolic and flavonoid contents in both the water and ethanol extracts. Various radical (DPPH, hydroxyl, and alkyl) scavenging activities of extracts from CW were higher than that of vitamin C. In addition, the antioxidant capacity measured as ferric reducing antioxidant power (FRAP), and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) as diammonium salt (ABTS) radical scavenging were higher than that of 2,6-di-tert-butyl-4-methylphenol (BHT), used as a positive control. The cytoprotective effect of CW extracts was also observed in tert-butyl hydroperoxide (t-BHP)-induced oxidative damage in Chang cells. These results showed that CW extracts have antioxidant properties through their ability to enhance cell viability, prevent reactive oxygen species (ROS) generation, and inhibit mitochondrial membrane depolarization. The antioxidant potency of the CW extracts could be exploited for their health promoting potential. 相似文献
12.
Tingjun Fan Yanan Zhang Lingling Yang Xiuxia Yang Guojian Jiang Miaomiao Yu Rishan Cong 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2009,152(2):144-149
To determine effective activators of crab hemocyanin (Hc) and the properties of Hc-derived phenoloxidase (HdPO), Hc, for the first time, was purified from hemolymph of Charybdis japonica, and the properties of activated HdPO were studied by using L-DOPA as a substrate. Three distinct subunits were isolated, and each had a molecular mass of about 80, 75 and 70 kDa, respectively. SDS and HLS were much effective in conversion of Hc into HdPO whose PO activity was optimal at pH 7.0 and temperature of 40 °C. The Km value of the HdPO was 2.90 mM for L-DOPA and 7.33 mM for tyrosine. The PO activity of HdPO was most sensitive to 1-phenyl-2-thiourea, cysteine and ascorbic acid, and much sensitive to thio urea and sodium sulfite. Based on its inhibition characteristics and the substrate specificity, this HdPO could be classified as a kind of tyrosinase-type phenoloxidase. The PO activity of HdPO was also strongly inhibited by Cu2+, Zn2+, ethylenediaminetetraacetic acid (EDTA) and diethyldithiocarbamate (DETC). The results with EDTA, DETC, and some metal ions, combined with the perfect recovery effect of Cu2+ on DETC-inhibited PO activity, indicate that the HdPO is a kind of copper-containing metalloenzyme. All these imply that the Hc, as an oxygen carrier, can be activated to have PO activities by SDS or HLS, and the activated HdPO has the properties of a tyrosinase-type copper-containing phenoloxidase. This study makes us to understand more easily the multifunctions of crustacean Hc in oxygen carrier and melaninization at certain stresses in host defence as well. 相似文献
13.
Jatinder Kumar Priyanka Dhar Amol B. Tayade Damodar Gupta Om P. Chaurasia Dalip K. Upreti Kiran Toppo Rajesh Arora M. R. Suseela Ravi B. Srivastava 《PloS one》2015,10(2)
The freshwater alga Spirogyra porticalis (Muell.) Cleve, a filamentous charophyte, collected from the Indian trans-Himalayan cold desert, was identified on the basis of morpho-anatomical characters. Extracts of this alga were made using solvents of varying polarity viz. n-hexane, acetonitrile, methanol and water. The antioxidant capacities and phenolic profile of the extracts were estimated. The methanol extract showing highest antioxidant capacity and rich phenolic attributes was further investigated and phytochemical profiling was conducted by gas chromatography-mass spectrometry (GC/MS) hyphenated technique. The cytotoxic activity of methanol extract was evaluated on human hepatocellular carcinoma HepG2 and colon carcinoma RKO cell lines. The anti-hypoxic effect of methanol extract of the alga was tested on in vivo animal system to confirm its potential to ameliorate oxidative stress. The antioxidant assays viz. ferric reducing antioxidant power (FRAP), 2,2''-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH) and nitric oxide (NO) radical scavenging capacities, β-carotene-linoleic acid bleaching property and lipid peroxidation exhibited analogous results, wherein the algal extracts showed significantly high antioxidant potential. The extracts were also found to possess high content of total proanthocyanidin, flavonoid and polyphenol. GC/MS analysis revealed the presence of thirteen chemotypes in the methanol extract representing different phytochemical groups like fatty acid esters, sterols, unsaturated alcohols, alkynes etc. with substantial phyto-pharmaceutical importance. The methanol extract was observed to possess anticancer activity as revealed from studies on HepG2 and RKO cell lines. In the present study, S. porticalis methanol extract also provided protection from hypoxia-induced oxidative stress and accelerated the onset of adaptative changes in rats during exposure to hypobaric hypoxia. The bioactive phytochemicals present in this trans-Himalayan alga are of enormous interest and can be utilized sustainably for discovery of novel drugs against oxidative stress. 相似文献
14.
Effect of pH and Chelating Agents on the Heat Resistance and Viability of Salmonella typhimurium Tm-1 and Salmonella senftenberg 775W in Egg White 总被引:2,自引:1,他引:1
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Supplementation of egg white at pH 8.9 with 5 mg of disodium ethylenediaminetetraacetic acid (EDTA) per ml resulted in a kill of Salmonella typhimurium Tm-1 of greater than 106 per ml after 28 days at 2 C. While at 28 C, supplementation with 7 mg of EDTA per ml resulted in approximately a 106 kill in less than 24 hr. Kena supplementation at 40 mg/ml of egg white resulted in a kill of S. typhimurium Tm-1 of greater than 106 after approximately 60 hr of storage at 28 C. This is in contrast to no reduction in viable count in unsupplemented egg white stored at 2 C and a 100-fold increase in viable count in that stored at 28 C. Supplementation of egg white with EDTA at 7 mg/ml or with Kena at 10 mg/ml also affected the heat resistant characteristics of the two organisms at 52.5 C, reducing the time required to kill 90% of the population (D value) at any pH by a factor of 2 to 6. There was a synergistic effect between EDTA and lactic acid when lactic acid was used to adjust EDTA-supplemented egg white to an acidic pH (5.3) which greatly decreased the heat resistance of Salmonella senftenberg 775W (from 100D to D). 相似文献
15.
The antioxidant potential of N-acetylcysteine amide (NACA), also known as AD4, was assessed by employing different in vitro assays. These included reducing power, free radical scavenging capacities, peroxidation inhibiting activity through linoleic acid emulsion system and metal chelating capacity, as compared to NAC and three widely used antioxidants, α-tocopherol, ascorbic acid and butylated hydroxytoluene (BHT). Of the antioxidant properties that were investigated, NACA was shown to possess higher 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging ability and reducing power than NAC, at all the concentrations, whereas the scavenging ability of H2O2 differed with concentration. While NACA had greater H2O2 scavenging capacity at the highest concentration, NAC was better than NACA at lower concentrations. NAC and NACA had a 60% and 55% higher ability to prevent β-carotene bleaching, respectively, as compared to control. The chelating activity of NACA was more than 50% that of the metal chelating capacity of EDTA and four and nine times that of BHT and α-tocopherol, respectively. When compared to NACA and NAC; α-tocopherol had higher DPPH scavenging abilities and BHT and α-tocopherol had better β-carotene bleaching power. These findings provide evidence that the novel antioxidant, NACA, has indeed enhanced the antioxidant properties of NAC. 相似文献
16.
Sanjay Guleria A. K. Tiku Gurjinder Singh Apurva Koul Sahil Gupta Subhash Rana 《Journal of plant biochemistry and biotechnology.》2013,22(1):9-15
Antioxidant activities and phenolic contents of 26 species extracts from 20 botanical families grown in north-western Himalaya were investigated. Antioxidant activities were determined using DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging and ferric reducing antioxidant power (FRAP) assays. Total phenolic content (TPC) was determined using a Folin-Ciocalteu assay. Quantitative and qualitative analysis of phenolic compounds was also carried out by reverse phase high performance liquid chromatography (RP-HPLC) using diode array detector (DAD). Major phenolics determined using RP-HPLC in analyzed species were gallic acid, chlorogenic acid, p-hydroxy benzoic acid, caffeic acid, vanillic acid, syringic acid, p-coumaric acid and ferulic acid. Antiradical efficiency (1/EC50) determined using DPPH radical scavenging assay ranged from 0.13 to 5.46. FRAP values ranged from 8.66 to 380.9 μmol Fe(II)/g dw. Similarly, the total phenolic content in the analyzed species varied from 3.01 to 69.96 mg of gallic acid equivalents (GAE)/g dry weight. Gallic acid was found in the majority of the samples, being most abundant compound in Syzygium cumini bark (92.64 mg/100 g dw). Vanillic acid was the predominant phenolic compound in Picrorhiza kurroa root stolen (161.2 mg/100 g dry weight). The medicinal plants with highest antioxidant activities were Taxus baccata and Syzygium cumini. A significant positive correlation, R 2?=?0.9461 and R 2?=?0.9112 was observed between TPC determined using Folin-Ciocalteu method and antiradical efficiency and FRAP values respectively, indicating that phenolic compounds are the major contributor of antioxidant activity of these medicinal plants. 相似文献
17.
Suresh Yarrappagaari Rajasekar Gutha Lohitha Narayanaswamy Lavanya Thopireddy Lakshminarsimhulu Benne Syed Siraj Mohiyuddin V. Vijayakumar Rajeswara Reddy Saddala 《Saudi Journal of Biological Sciences》2020,27(12):3601-3614
The current research is to develop an easy and eco-friendly method for the synthesis of three different concentrations of silver nanoparticles (1mMCvAgNPs, 2mMCvAgNPs and 3mMCvAgNPs) using aqueous whole plant extract of Cleome viscosa and to evaluate their antibacterial, antioxidant and antidiabetic properties. CvAgNPs were characterized by Using UV–vis spectrophotometer, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM) and transmission electron microscope (TEM). The formation of CvAgNPs was confirmed by the observation of band between 250 nm to 600 nm UV–vis spectrum. The crystalline structure of CvAgNPs with a face-centered cubic (FCC) was confirmed by XRD. The responsible phytochemicals for the reduction and capping material of CvAgNPs were observed with FT-IR. The SEM analysis confirmed the size and shapes of CvAgNPs. The CvAgNPs have shown the rich content of total phenolic and total flavonoid components. The CvAgNPs have shown significant antibacterial activity on multi drug resistance Gram-negative and Gram-positive bacteria and also have shown significant strong antioxidant activities (DPPH, ABTS, H2O2 scavenging, Phosphomolybdenum assay and reducing power). The inhibitory action of CvAgNPs on α-glucosidase and α-amylase was stronger than the inhibitory action of acarbose. To best of our knowledge, this is the first attempt on the synthesis of AgNPs using C. viscosa whole plant aqueous extract. The synthesized CvAgNPs exhibited good antimicrobial, antioxidant and antidiabetic properties. Hence, to validate our results, the in vivo studies at the molecular level are needed to develop Cleome viscosa as an antibacterial, antioxidant and anti-diabetic agent. 相似文献
18.
The antioxidant potential of N-acetylcysteine amide (NACA), also known as AD4, was assessed by employing different in vitro assays. These included reducing power, free radical scavenging capacities, peroxidation inhibiting activity through linoleic acid emulsion system and metal chelating capacity, as compared to NAC and three widely used antioxidants, alpha-tocopherol, ascorbic acid and butylated hydroxytoluene (BHT). Of the antioxidant properties that were investigated, NACA was shown to possess higher 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging ability and reducing power than NAC, at all the concentrations, whereas the scavenging ability of H(2)O(2) differed with concentration. While NACA had greater H(2)O(2) scavenging capacity at the highest concentration, NAC was better than NACA at lower concentrations. NAC and NACA had a 60% and 55% higher ability to prevent beta-carotene bleaching, respectively, as compared to control. The chelating activity of NACA was more than 50% that of the metal chelating capacity of EDTA and four and nine times that of BHT and alpha-tocopherol, respectively. When compared to NACA and NAC; alpha-tocopherol had higher DPPH scavenging abilities and BHT and alpha-tocopherol had better beta-carotene bleaching power. These findings provide evidence that the novel antioxidant, NACA, has indeed enhanced the antioxidant properties of NAC. 相似文献
19.
A Cytochemical Study of Extracellular Sheaths Associated with Rigidoporus lignosus during Wood Decay 总被引:2,自引:0,他引:2
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M. Nicole H. Chamberland D. Rioux N. Lecours B. Rio J. P. Geiger G. B. Ouellette 《Applied microbiology》1993,59(8):2578-2588
An ultrastructural and cytochemical investigation of the development of Rigidoporus lignosus, a white-rot fungus inoculated into wood blocks, was carried out to gain better insight into the structure and role of the extracellular sheaths produced by this fungus during wood degradation. Fungal sheaths had a dense or loose fibrillar appearance and were differentiated from the fungal cell wall early after wood inoculation. Close association between extracellular fibrils and wood cell walls was observed at both early and advanced stages of wood alteration. Fungal sheaths were often seen deep in host cell walls, sometimes enclosing residual wood fragments. Specific gold probes were used to investigate the chemical nature of R. lignosus sheaths. While labeling of chitin, pectin, β-1,4- and β-1,3-glucans, β-glucosides, galactosamine, mannose, sialic acid, RNA, fucose, and fimbrial proteins over fungal sheaths did not succeed, galactose residues and laccase (a fungal phenoloxidase) were found to be present. The positive reaction of sheaths with the PATAg test indicates that polysaccharides such as β-1,6-glucans are important components. Our data suggest that extracellular sheaths produced by R. lignosus during host cell colonization play an important role in wood degradation. Transportation of lignin-degrading enzymes by extracellular fibrils indicates that alteration of plant polymers may occur within fungal sheaths. It is also proposed that R. lignosus sheaths may be involved in recognition mechanisms in fungal cell-wood surface interactions. 相似文献
20.
《Animal : an international journal of animal bioscience》2022,16(12):100677
Weaning is a critical phase in intensive piglet production marked by the frequent occurrence of digestive disorders posing health and economic burden. To stave off such weaning-related problems, antibiotics and supplements containing high levels of ZnO are often used. In this study, we investigated whether natural fibres obtained from two plants known for their dietary fibre profile and antioxidant properties: flax (Linum usitatissimum L.) and hemp (Cannabis sativa L.), can serve as a health-promoting diet supplement. The study was conducted on a total of 191 Polish Large White piglets from 18 L, from their birth to 56 days of age. Piglets were divided by litters into six groups: W1.5, F1.5, H1.5, W2.0, F2.0, and H2.0. Groups W1.5, F1.5, and H1.5 received feed supplemented with 1.5% fibre from wood cellulose (W), flax (F), and hemp (H), respectively, while groups W2.0, F2.0, and H2.0 received feed with a higher 2.0% content of the same fibres. Flax and hemp fibres were characterised by a complex composition, antioxidant properties due to the presence of phenolic acids, and low risk of mycotoxin contamination. Flax fibre resulted in best weight gains and feed conversion ratio (P ≤ 0.05) of piglets, while hemp fibre had higher positive effect on antioxidant status (P ≤ 0.05) compared to the other two fibre additives. Neither flax nor hemp fibres had any adverse effect on the haematological and biochemical blood parameters. Piglets receiving a diet with 1.5% added fibre showed better growth performance, while diet supplementation with 2% fibre had a beneficial effect on the content of butyric acid in the small intestinal chyme (P ≤ 0.05). The results suggested that both flax and hemp fibres can be innovative feed additives for weaned piglets. However, further studies should be conducted in commercial farms, as the effects of dietary fibre could vary in more challenging environmental conditions. 相似文献