Displaying publications 21 - 40 of 77 in total

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  1. Shaari K, Suppaiah V, Wai LK, Stanslas J, Tejo BA, Israf DA, et al.
    Bioorg Med Chem, 2011 Nov 1;19(21):6340-7.
    PMID: 21958738 DOI: 10.1016/j.bmc.2011.09.001
    A bioassay-guided investigation of Melicope ptelefolia Champ ex Benth (Rutaceae) resulted in the identification of an acyphloroglucinol, 2,4,6-trihydroxy-3-geranylacetophenone or tHGA, as the active principle inhibiting soybean 15-LOX. The anti-inflammatory action was also demonstrated on human leukocytes, where the compound showed prominent inhibitory activity against human PBML 5-LOX, with an IC(50) value of 0.42 μM, very close to the effect produced by the commonly used standard, NDGA. The compound concentration-dependently inhibited 5-LOX product synthesis, specifically inhibiting cysteinyl leukotriene LTC(4) with an IC(50) value of 1.80 μM, and showed no cell toxicity effects. The anti-inflammatory action does not seem to proceed via redox or metal chelating mechanism since the compound tested negative for these bioactivities. Further tests on cyclooxygenases indicated that the compound acts via a dual LOX/COX inhibitory mechanism, with greater selectivity for 5-LOX and COX-2 (IC(50) value of 0.40 μM). The molecular features that govern the 5-LOX inhibitory activity was thus explored using in silico docking experiments. The residues Ile 553 and Hie 252 were the most important residues in the interaction, each contributing significant energy values of -13.45 (electrostatic) and -5.40 kcal/mol (electrostatic and Van der Waals), respectively. The hydroxyl group of the phloroglucinol core of the compound forms a 2.56Å hydrogen bond with the side chain of the carboxylate group of Ile 553. Both Ile 553 and Hie 252 are crucial amino acid residues which chelate with the metal ion in the active site. Distorting the geometry of these ligands could be the reason for the inhibition activity shown by tHGA. The molecular simulation studies supported the bioassay results and served as a good model for understanding the way tHGA binds in the active site of human 5-LOX enzyme.
    Matched MeSH terms: Free Radical Scavengers/pharmacology
  2. Haleagrahara N, Julian V, Chakravarthi S
    Cardiovasc Toxicol, 2011 Dec;11(4):373-81.
    PMID: 21796404 DOI: 10.1007/s12012-011-9132-0
    This study investigated the cardioprotective effect of N-acetylcysteine (NAC) on isoproterenol (ISO)-induced cardiotoxicity in rats. Male Sprague-Dawley rats were divided into control, NAC alone (100 mg/kg BW orally for 14 days), ISO-control (85 mg/kg BW), and ISO with NAC (for 14 days). Serum creatine kinase-MB and Lactate dehydrogenase were measured. From the heart homogenate lipid hydroperoxides (LPO), superoxide dismutase (SOD), total glutathione (GSH), and 8-isoprostane (IP) were measured. Histopathological examination of the heart was also carried out. There was a significant increase (P free radicals-induced damage to the myocardium.
    Matched MeSH terms: Free Radical Scavengers/pharmacology*
  3. Kadhum AA, Al-Amiery AA, Musa AY, Mohamad AB
    Int J Mol Sci, 2011;12(9):5747-61.
    PMID: 22016624 DOI: 10.3390/ijms12095747
    The antioxidant activity of two synthesized coumarins namely, N-(4,7-dioxo-2- phenyl-1,3-oxazepin-3(2H,4H,7H)-yl)-2-(2-oxo-2H-chromen-4-yloxy)acetamide 5 and N-(4-oxo-2-phenylthiazolidin-3-yl)-2-(2-oxo-2H-chromen-4-yloxy)acetamide 6 were studied with the DPPH, hydrogen peroxide and nitric oxide radical methods and compared with the known antioxidant ascorbic acid. Compounds 5 and 6 were synthesized in a good yield from the addition reaction of maleic anhydride or mercaptoacetic acid to compound 4, namely N'-benzylidene-2-(2-oxo-2H-chromen-4-yloxy)acetohydrazide. Compound 4 was synthesized by the condensation of compound 3, namely 2-(2-oxo-2H-chromen-4-yloxy) acetohydrazide, with benzaldehyde. Compound 3, however, was synthesized from the addition of hydrazine to compound 2, namely ethyl 2-(2-oxo-2H-chromen-4-yloxy)acetate, which was synthesized from the reaction of ethyl bromoacetate with 4-hydroxycoumarin 1. Structures for the synthesized coumarins 2-6 are proposed on the basis of spectroscopic evidence.
    Matched MeSH terms: Free Radical Scavengers/pharmacology
  4. Yim HS, Chye FY, Lee MY, Matanjun P, How SE, Ho CW
    Int J Med Mushrooms, 2011;13(3):245-55.
    PMID: 22135876
    The present study aims to assess the antioxidant activities (AOA) and total phenolic content (TPC) of water extracts of selected edible wild mushrooms: Pleurotus porrigens, Schizophyllum commune, Hygrocybe conica, and Lentinus ciliatus. The AOA were evaluated against DPPH radical and ABTS radical cation scavenging ability, ferric-reducing antioxidant power (FRAP) and beta-carotene-linoleate bleaching (beta-CB) assays, and the Folin-Ciocalteu method for TPC. BHA was used as reference. P. porrigens showed significantly higher (p < 0.05) DPPH* scavenging ability (90.78 +/- 0.30%) and FRAP (6.37 +/- 0.22 mM FE/100g), while Sch. commune showed significantly higher (p < 0.05) ABTS*+ inhibition activity (94.96 +/- 0.70%) and beta-CB inhibition activity (94.18 +/- 0.17%), respectively. TPC was found in a descending order of P. poriggens > L. ciliatus = Pleurotus ostreatus (cultivated) > H. conica = Sch. commune. Positive correlation was observed between the AOA and TPC. When compared to BHA (2 mM), P. porrigens showed significantly higher (p < 0.05) DPPH* scavenging ability and reducing power, while Sch. commune showed comparable DPPH* scavenging ability and ABTS*+ inhibition activity. All the mushrooms have better ABTS*+ inhibition activity than BHA (1 mM). The beta-CB inhibition activity of BHA was significantly higher than those of edible wild mushrooms. The water extracts of edible wild mushrooms showed potent antioxidant activities compared to BHA to a certain extent.
    Matched MeSH terms: Free Radical Scavengers/pharmacology*
  5. Aisha AF, Abu-Salah KM, Alrokayan SA, Ismail Z, Abdulmajid AM
    Pak J Pharm Sci, 2012 Jan;25(1):7-14.
    PMID: 22186303
    Parkia speciosa Hassk is a traditional medicinal plant with strong antioxidant and hypoglycemic properties. This study aims to investigate the total phenolic content, antioxidant, cytotoxic and antiangiogenic effect of eight extracts from P. speciosa empty pods. The extracts were found to contain high levels of total phenols and demonstrated strong antioxidant effect in DPPH scavenging test. In rat aortic rings, P. speciosa extracts significantly inhibited the microvessel outgrowth from aortic tissue explants by more than 50%. The antiangiogenic activity was further confirmed by tube formation on matrigel matrix involving human endothelial cells. Cytotoxic effect was evaluated by XTT test on endothelial cells as a model of angiogenesis versus a panel of human cancer and normal cell lines. Basically the extracts did not show acute cytotoxicity. Morphology examination of endothelial cells indicated induction of autophagy characterized by formation of plenty of cytoplasmic vacuoles. The extracts were found to work by decreasing expression of vascular endothelial growth factor in endothelial cells.
    Matched MeSH terms: Free Radical Scavengers/pharmacology
  6. Yehye WA, Abdul Rahman N, Alhadi AA, Khaledi H, Weng NS, Ariffin A
    Molecules, 2012 Jun 25;17(7):7645-65.
    PMID: 22732881 DOI: 10.3390/molecules17077645
    A computer-aided predictions of antioxidant activities were performed with the Prediction Activity Spectra of Substances (PASS) program. Antioxidant activity of compounds 1, 3, 4 and 5 were studied using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and lipid peroxidation assays to verify the predictions obtained by the PASS program. Compounds 3 and 5 showed more inhibition of DPPH stable free radical at 10⁻⁴ M than the well-known standard antioxidant, butylated hydroxytoluene (BHT). Compound 5 exhibited promising in vitro inhibition of Fe²⁺-induced lipid peroxidation of the essential egg yolk as a lipid-rich medium (83.99%, IC₅₀ 16.07 ± 3.51 μM/mL) compared to α-tocopherol (α-TOH, 84.6%, IC₅₀ 5.6 ± 1.09 μM/mL). The parameters for drug-likeness of these BHT analogues were also evaluated according to the Lipinski’s “rule-of-five” (RO5). All the BHT analogues were found to violate one of the Lipinski’s parameters (LogP > 5), even though they have been found to be soluble in protic solvents. The predictive polar surface area (PSA) and absorption percent (% ABS) data allow us to conclude that they could have a good capacity for penetrating cell membranes. Therefore, one can propose these new multipotent antioxidants (MPAOs) as potential antioxidants for tackling oxidative stress and lipid peroxidation processes.
    Matched MeSH terms: Free Radical Scavengers/pharmacology
  7. Fakurazi S, Sharifudin SA, Arulselvan P
    Molecules, 2012 Jul 10;17(7):8334-50.
    PMID: 22781444 DOI: 10.3390/molecules17078334
    The aim of the study was to investigate the in vitro antioxidant properties Moringa oleifera Lam. (MO) extracts and its curative role in acetaminophen (APAP)-induced toxic liver injury in rats caused by oxidative damage. The total phenolic content and antioxidant properties of hydroethanolic extracts of different MO edible parts were investigated by employing an established in vitro biological assay. In the antihepatotoxic study, either flowers or leaves extract (200 mg/kg or 400 mg/kg, i.p) were administered an hour after APAP administration, respectively. N-Acetylcysteine was used as the positive control against APAP-induced hepatotoxicity. The levels of liver markers such as alanine aminotransferase (ALT) and the levels of oxidative damage markers including malondialdehyde (MDA), 4-hydroxynonenal (4-HNE) protein adduct, reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were analysed and compared between experimental groups. Among MO edible parts the flower extracts contain the highest total phenolic content and antioxidant capacity, followed by leaves extract. The oxidative marker MDA, as well as 4-HNE protein adduct levels were elevated and GSH, SOD and CAT were significantly decreased in groups treated with hepatotoxin. The biochemical liver tissue oxidative markers measured in the rats treated with MO flowers and leaves hydroethanolic extracts showed a significant (p < 0.05) reduction in the severity of the liver damage. The results of this study strongly indicate the therapeutic properties of MO hydroethanolic extracts against acute liver injury and thereby scientifically support its traditional use.
    Matched MeSH terms: Free Radical Scavengers/pharmacology
  8. Grace-Lynn C, Darah I, Chen Y, Latha LY, Jothy SL, Sasidharan S
    Molecules, 2012 Sep 19;17(9):11185-98.
    PMID: 22992785
    Lantadenes are pentacyclic triterpenoids present in the leaves of the plant Lantana camara. In the present study, in vitro antioxidant activity and free radical scavenging capacity of lantadene A was evaluated using established in vitro models such as ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picryl-hydrazyl (DPPH•), hydroxyl radical (OH•), nitric oxide radical (NO•), superoxide anion scavenging activities and ferrous ion chelating assay. Interestingly, lantadene A showed considerable in vitro antioxidant, free radical scavenging capacity activities in a dose dependant manner when compared with the standard antioxidant in nitric oxide scavenging, superoxide anion radical scavenging and ferrous ion chelating assay. These findings show that the lantadene A possesses antioxidant activity with different mechanism of actions towards the different free radicals tested. Since lantadene A is a very popular drug in modern medicine, it is a promising candidate for use as an antioxidant and hepatoprotective agent.
    Matched MeSH terms: Free Radical Scavengers/pharmacology
  9. Khalil I, Moniruzzaman M, Boukraâ L, Benhanifia M, Islam A, Islam N, et al.
    Molecules, 2012 Sep 20;17(9):11199-215.
    PMID: 22996344
    The aim of the present study was to characterize the physical, biochemical and antioxidant properties of Algerian honey samples (n = 4). Physical parameters, such as pH, moisture content, electrical conductivity (EC), total dissolved solids (TDS), color intensity, total sugar and sucrose content were measured. Several biochemical and antioxidant tests were performed to determine the antioxidant properties of the honey samples. The mean pH was 3.84 ± 0.01, and moisture the content was 13.21 ± 0.16%. The mean EC was 0.636 ± 0.001, and the mean TDS was 316.92 ± 0.92. The mean color was 120.58 ± 0.64 mm Pfund, and the mean 5-hydroxymethylfurfural (HMF) content was 21.49 mg/kg. The mean total sugar and reducing sugar contents were 67.03 ± 0.68 g/mL and 64.72 ± 0.52 g/g, respectively. The mean sucrose content was 2.29 ± 0.65%. High mean values of phenolic (459.83 ± 1.92 mg gallic acid/kg), flavonoid (54.23 ± 0.62 mg catechin/kg), ascorbic acid (159.70 ± 0.78 mg/kg), AEAC (278.15 ± 4.34 mg/kg), protein (3381.83 ± 6.19 mg/kg) and proline (2131.47 ± 0.90) contents, as well as DPPH (39.57% ± 4.18) and FRAP activities [337.77 ± 1.01 µM Fe (II)/100 g], were also detected, indicating that Algerian honey has a high antioxidant potential. Strong positive correlations were found between flavonoid, proline and ascorbic acid contents and color intensity with DPPH and FRAP values. Thus, the present study revealed that Algerian honey is a good source of antioxidants.
    Matched MeSH terms: Free Radical Scavengers/pharmacology
  10. Mahdi-Pour B, Jothy SL, Latha LY, Chen Y, Sasidharan S
    Asian Pac J Trop Biomed, 2012 Dec;2(12):960-5.
    PMID: 23593576 DOI: 10.1016/S2221-1691(13)60007-6
    To investigate the antioxidant activity of methanolic extracts of Lantana camara (L. camara) various parts and the determination of their total phenolics content.
    Matched MeSH terms: Free Radical Scavengers/pharmacology
  11. Alnajar ZA, Abdulla MA, Ali HM, Alshawsh MA, Hadi AH
    Molecules, 2012;17(3):3547-59.
    PMID: 22433579 DOI: 10.3390/molecules17033547
    Melastoma malabathricum (MM) is a well-known plant in Malaysian traditional medicine, locally known as senduduk. Its ethanol and aqueous extracts have been used in the present investigation to study the immunomodulatory role on human peripheral blood mononuclear cell (PBMC), and the DPPH, ABTS and FRAP free radical scavenging activities were also measured. Total flavonoids and total phenolic contents were assayed and the antibacterial effect was tested against four species of bacteria; two Gram-positive (Staphylococcus aureus and Streptococcus agalactiae) and two Gram-negative (Escherichia coli and Klebsilla pneumonia). The tests were carried out using the disc diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) methods. Moreover, the acute toxicity was evaluated in vivo on the ethanol extract of MM to establish its safety when administered orally. In our results, both extracts of MM showed abilities to scavenge DPPH and ABTS free radicals, IC(50) values: (11.599 ± 0.84, 10.573 ± 0.58 µmol/L) and (62.657 ± 0.78, 63.939 ± 0.48 µmol/L) for ethanol and aqueous extracts respectively. Indeed the ethanol extract evidenced high phenolic content (384.33 ± 0.005 mg/g), flavonoids contents (85.8 ± 0.009 mg/g) and ferric reducing antioxidant power (33,590 ± 0.038 mmol/g), with high activity against S. aureus and S. agalactiae (11 ± 0.3 and 12 ± 0.6 mm inhibition zones). Likewise, the percentage of peripheral blood mononuclear cells (PBMC) viability was increased in response to MM, IC(50) values (1.781 ± 1.2 and 6.545 ± 0.93 µg/mL) for ethanol and aqueous extracts, respectively. In addition, our results showed that the MM extract is safe even at a high dose of 5,000 mg/kg and has no oral toxicity. These findings suggest the excellent medicinal bioactivity of MM and explain the popularity of this plant in the folk medicine as a remedy for different illnesses.
    Matched MeSH terms: Free Radical Scavengers/pharmacology
  12. Alshawsh MA, Abdulla MA, Ismail S, Amin ZA, Qader SW, Hadi HA, et al.
    Molecules, 2012;17(5):5385-95.
    PMID: 22569417 DOI: 10.3390/molecules17055385
    Orthosiphon stamineus is considered an important traditional folk medicine. In this study ethanol and aqueous extracts of O. stamineus were evaluated in vitro for their antioxidant, antimicrobial as well as for their immunomodulatory properties on human peripheral blood mononuclear cells (PBMCs). The DPPH radical scavenging method was used for the determination of antioxidant activity, while the antibacterial efficacy was investigated by both disc diffusion method and Minimum Inhibitory Concentration (MIC) against four bacterial strains (Gram-positive and Gram-negative). Furthermore, the immunomodulatory potential of the extracts was investigated through the MTT assay. Aqueous extract of O. stamineus exhibited significant free radical scavenging activity with IC₅₀ 50 9.6 µg/mL, whereas the IC₅₀ for the ethanol extract was 21.4 µg/mL. The best antimicrobial activity was shown by the aqueous extract of O. stamineus against Staphylococcus aureus, with inhibition zone of 10.5 mm and MIC value 1.56 mg/mL. Moreover, the results observed from the MTT assay showed that both plant extracts stimulated the PBMCs proliferation in vitro in a concentration-dependent manner, but the aqueous extract has remarkable activity against PBMCs. These findings indicate that O. stamineus showed high antioxidant activity and may be considered as an immunomodulatory agent.
    Matched MeSH terms: Free Radical Scavengers/pharmacology*
  13. Kassim M, Mansor M, Suhaimi A, Ong G, Yusoff KM
    Int J Mol Sci, 2012;13(9):12113-29.
    PMID: 23109904 DOI: 10.3390/ijms130912113
    Monocytes and macrophages are part of the first-line defense against bacterial, fungal, and viral infections during host immune responses; they express high levels of proinflammatory cytokines and cytotoxic molecules, including nitric oxide, reactive oxygen species, and their reaction product peroxynitrite. Peroxynitrite is a short-lived oxidant and a potent inducer of cell death. Honey, in addition to its well-known sweetening properties, is a natural antioxidant that has been used since ancient times in traditional medicine. We examined the ability of Gelam honey, derived from the Gelam tree (Melaleuca spp.), to scavenge peroxynitrite during immune responses mounted in the murine macrophage cell line RAW 264.7 when stimulated with lipopolysaccharide/interferon-γ (LPS/IFN-γ) and in LPS-treated rats. Gelam honey significantly improved the viability of LPS/IFN-γ-treated RAW 264.7 cells and inhibited nitric oxide production-similar to the effects observed with an inhibitor of inducible nitric oxide synthase (1400W). Furthermore, honey, but not 1400W, inhibited peroxynitrite production from the synthetic substrate 3-morpholinosydnonimine (SIN-1) and prevented the peroxynitrite-mediated conversion of dihydrorhodamine 123 to its fluorescent oxidation product rhodamine 123. Honey inhibited peroxynitrite synthesis in LPS-treated rats. Thus, honey may attenuate inflammatory responses that lead to cell damage and death, suggesting its therapeutic uses for several inflammatory disorders.
    Matched MeSH terms: Free Radical Scavengers/pharmacology*
  14. Mustahil NA, Sukari MA, Abdul AB, Ali NA, Lian GE
    Pak J Pharm Sci, 2013 Mar;26(2):391-5.
    PMID: 23455212
    Phytochemicals investigation on rhizomes of Alpinia mutica has afforded five compounds namely 5,6-dehydrokawain (1), flavokawin B (2), pinostrobin (3) and pinocembrin (4) together with β-sitosterol (5). All crude extracts of the plant demonstrated strong cytotoxicity against CEMss (human T4 lymphoblastoid) cancer cells with IC50 values less than 19 μg/mL, while flavokawin B (2) was the most cytotoxic isolate with IC50 value 1.86±0.37 μg/mL. Most of the crude extracts and isolated compounds showed weak activity in antimicrobial and diphenylpicrylhydrazyl (DPPH) radical scavenging activity tests.
    Matched MeSH terms: Free Radical Scavengers/pharmacology
  15. Paydar M, Wong YL, Moharam BA, Wong WF, Looi CY
    Pak J Biol Sci, 2013 Oct 15;16(20):1212-5.
    PMID: 24506026
    Sanchezia speciosa, is a bushy shrub from Acanthaceae family which commonly grows in tropical areas of South and Central America. In this study, we employed MTT assay to test the cytotoxicity of that methanolic fraction of S. speciosa leaves on MCF-7 human breast cancer, SK-MEL-5 human malignant melanoma and human umbilical vein endothelial cells, HUVEC cells. The extract showed highest activity on MCF-7 and moderate cytotoxicity towards SK-MEL-5. In contrast, the extract demonstrated lowest cell growth inhibition activity on HUVEC cells, indicating better selectivity compare to standard drug, doxorubicin. In addition, we also performed ORAC assay to determine the radical scavenging capacity of methanolic extract of S. speciosa leaves. The extract exhibited nearly similar anti-oxidant activity as quercetin, suggesting S. speciosa leaves as a potential source of natural anti-oxidant. To the best of our knowledge, this is the first report on anti-oxidant and cytotoxic activity of S. speciosa.
    Matched MeSH terms: Free Radical Scavengers/pharmacology
  16. Lim CY, Mat Junit S, Abdulla MA, Abdul Aziz A
    PLoS One, 2013;8(7):e70058.
    PMID: 23894592 DOI: 10.1371/journal.pone.0070058
    BACKGROUND: Tamarindus indica (T. indica) is a medicinal plant with many biological activities including anti-diabetic, hypolipidaemic and anti-bacterial activities. A recent study demonstrated the hypolipidaemic effect of T. indica fruit pulp in hamsters. However, the biochemical and molecular mechanisms responsible for these effects have not been fully elucidated. Hence, the aims of this study were to evaluate the antioxidant activities and potential hypocholesterolaemic properties of T. indica, using in vitro and in vivo approaches.

    METHODOLOGY/PRINCIPAL FINDINGS: The in vitro study demonstrated that T. indica fruit pulp had significant amount of phenolic (244.9 ± 10.1 mg GAE/extract) and flavonoid (93.9 ± 2.6 mg RE/g extract) content and possessed antioxidant activities. In the in vivo study, hamsters fed with high-cholesterol diet for ten weeks showed elevated serum triglyceride, total cholesterol, HDL-C and LDL-C levels. Administration of T. indica fruit pulp to hypercholesterolaemic hamsters significantly lowered serum triglyceride, total cholesterol and LDL-C levels but had no effect on the HDL-C level. The lipid-lowering effect was accompanied with significant increase in the expression of Apo A1, Abcg5 and LDL receptor genes and significant decrease in the expression of HMG-CoA reductase and Mtp genes. Administration of T. indica fruit pulp to hypercholesterolaemic hamsters also protected against oxidative damage by increasing hepatic antioxidant enzymes, antioxidant activities and preventing hepatic lipid peroxidation.

    CONCLUSION/SIGNIFICANCE: It is postulated that tamarind fruit pulp exerts its hypocholesterolaemic effect by increasing cholesterol efflux, enhancing LDL-C uptake and clearance, suppressing triglyceride accumulation and inhibiting cholesterol biosynthesis. T. indica fruit pulp has potential antioxidative effects and is potentially protective against diet-induced hypercholesterolaemia.

    Matched MeSH terms: Free Radical Scavengers/pharmacology
  17. Ali Hassan SH, Fry JR, Abu Bakar MF
    Biomed Res Int, 2013;2013:138950.
    PMID: 24288662 DOI: 10.1155/2013/138950
    Garcinia parvifolia belongs to the same family as mangosteen (Garcinia mangostana), which is known locally in Sabah as "asam kandis" or cherry mangosteen. The present study was conducted to determine the phytochemicals content (total phenolic, flavonoid, anthocyanin, and carotenoid content) and antioxidant and acetylcholinesterase inhibition activity of the flesh and peel of G. parvifolia. All samples were freeze-dried and extracted using 80% methanol and distilled water. For the 80% methanol extract, the flesh of G. parvifolia displayed higher phenolic and flavonoid contents than the peel, with values of 7.2 ± 0.3 mg gallic acid equivalent (GAE)/g and 5.9 ± 0.1 mg rutin equivalent (RU)/g, respectively. Anthocyanins were detected in the peel part of G. parvifolia but absent in the flesh. The peel of G. parvifolia displayed higher total carotenoid content as compared to the flesh part with the values of 17.0 ± 0.3 and 3.0 ± 0.0 mg β-carotene equivalents (BC)/100 g, respectively. The free-radical scavenging, ferric reducing, and acetylcholinesterase inhibition effect of the flesh were higher as compared to the peel in both extracts. These findings suggested that the edible part of G. parvifolia fruit has a potential as a natural source of antioxidant and anti-Alzheimer's agents.
    Matched MeSH terms: Free Radical Scavengers/pharmacology
  18. Kassim M, Mansor M, Kamalden TA, Shariffuddin II, Hasan MS, Ong G, et al.
    Shock, 2014 Aug;42(2):154-60.
    PMID: 24667629 DOI: 10.1097/SHK.0000000000000179
    Excessive free radical production by immune cells has been linked to cell death and tissue injury during sepsis. Peroxynitrite is a short-lived oxidant and a potent inducer of cell death that has been identified in several pathological conditions. Caffeic acid phenethyl ester (CAPE) is an active component of honeybee products and exhibits antioxidant, anti-inflammatory, and immunomodulatory activities. The present study examined the ability of CAPE to scavenge peroxynitrite in RAW 264.7 murine macrophages stimulated with lipopolysaccharide/interferon-γ that was used as an in vitro model. Conversion of 123-dihydrorhodamine to its oxidation product 123-rhodamine was used to measure peroxynitrite production. Two mouse models of sepsis (endotoxemia and cecal ligation and puncture) were used as in vivo models. The level of serum 3-nitrotyrosine was used as an in vivo marker of peroxynitrite. The results demonstrated that CAPE significantly improved the viability of lipopolysaccharide/interferon-γ-treated RAW 264.7 cells and significantly inhibited nitric oxide production, with effects similar to those observed with an inhibitor of inducible nitric oxide synthase (1400W). In addition, CAPE exclusively inhibited the synthesis of peroxynitrite from the artificial substrate SIN-1 and directly prevented the peroxynitrite-mediated conversion of dihydrorhodamine-123 to its fluorescent oxidation product rhodamine-123. In both sepsis models, CAPE inhibited cellular peroxynitrite synthesis, as evidenced by the absence of serum 3-nitrotyrosine, an in vivo marker of peroxynitrite. Thus, CAPE attenuates the inflammatory responses that lead to cell damage and, potentially, cell death through suppression of the production of cytotoxic molecules such as nitric oxide and peroxynitrite. These observations provide evidence of the therapeutic potential of CAPE treatment for a wide range of inflammatory disorders.
    Matched MeSH terms: Free Radical Scavengers/pharmacology*
  19. Ghasemzadeh A, Nasiri A, Jaafar HZ, Baghdadi A, Ahmad I
    Molecules, 2014 Oct 30;19(11):17632-48.
    PMID: 25361426 DOI: 10.3390/molecules191117632
    In the current study, changes in secondary metabolite synthesis and the pharmaceutical quality of sabah snake grass leaves and buds were considered in relation to plant age (1 month, 6 months, and 1 year old). The activity of the enzyme chalcone synthase (CHS, EC 2.3.1.74) was measured, as it is a key enzyme for flavonoid production. Significant differences in total flavonoid (TF) production were observed between the three plant growth periods and the different plant parts. The highest contents of TF (6.32 mg/g dry weight [DW]) and total phenolic (TP) (18.21 mg/g DW) were recorded in 6-month-old buds. Among the flavonoids isolated in this study the most important ones based on concentration were from high to low as follows: catechin > quercetin > kaempferol > luteolin. Production of phenolic acids increased from 1 to 6 months, but after 6 months up to 1 year of age, they decreased significantly. The highest contents of caffeic acid (0.307 mg/g DW) and gallic acid (5.96 mg/g DW) were recorded in 1-year and 6-month-old buds, respectively. The lowest and highest activity of CHS was recorded in 1-month and 6-month-old buds with values of 3.6 and 9.5 nkat/mg protein, respectively. These results indicate that the increment in flavonoids and phenolic acids in 6-month-old buds can be attributed to an increase in CHS activity. The highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) activity was observed in the extract of 1-year-old buds followed by 6-month-old buds, with 50% of free radical scavenging (IC50) values of 64.6 and 73.5 µg/mL, respectively. Interestingly, a ferric reducing antioxidant power (FRAP) assay showed a higher activity in 6-month-old buds (488 μM of Fe(II)/g) than in 1-year-old buds (453 μM of Fe(II)/g), in contrast to the DPPH result. Significant correlations (p < 0.05) were observed between CHS enzyme activity and FRAP activity, TF, catechin, and kaempferol content. Extracts of 6-month-old bud exhibited a significant in vitro anticancer activity against HeLa cancer cells with IC50 value of 56.8 µg/mL. These results indicate that early harvesting of snake grass (6-month-old) may yield increased concentrations of secondary metabolites, which are potent antioxidant compounds.
    Matched MeSH terms: Free Radical Scavengers/pharmacology
  20. Ahmad R, Baharum SN, Bunawan H, Lee M, Mohd Noor N, Rohani ER, et al.
    Molecules, 2014 Nov 20;19(11):19220-42.
    PMID: 25420073 DOI: 10.3390/molecules191119220
    The aim of this research was to identify the volatile metabolites produced in different organs (leaves, stem and roots) of Polygonum minus, an important essential oil producing crop in Malaysia. Two methods of extraction have been applied: Solid Phase Microextraction (SPME) and hydrodistillation coupled with Gas Chromatography-Mass Spectrometry (GC-MS). Approximately, 77 metabolites have been identified and aliphatic compounds contribute significantly towards the aroma and flavour of this plant. Two main aliphatic compounds: decanal and dodecanal were found to be the major contributor. Terpenoid metabolites were identified abundantly in leaves but not in the stem and root of this plant. Further studies on antioxidant, total phenolic content, anticholinesterase and antimicrobial activities were determined in the essential oil and five different extracts. The plant showed the highest DPPH radical scavenging activity in polar (ethanol) extract for all the tissues tested. For anti-acetylcholinesterase activity, leaf in aqueous extract and methanol extract showed the best acetylcholinesterase inhibitory activities. However, in microbial activity, the non-polar extracts (n-hexane) showed high antimicrobial activity against Methicillin-resistant Staphylococcus aureus (MRSA) compared to polar extracts. This study could provide the first step in the phytochemical profiles of volatile compounds and explore the additional value of pharmacology properties of this essential oil producing crop Polygonum minus.
    Matched MeSH terms: Free Radical Scavengers/pharmacology
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