Displaying publications 101 - 120 of 657 in total

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  1. Othman SH, Shapi'i RA, Ronzi NDA
    Carbohydr Polym, 2024 Apr 01;329:121735.
    PMID: 38286535 DOI: 10.1016/j.carbpol.2023.121735
    Starch biopolymer films incorporated with chitosan nanoparticles (CNP) or starch/CNP films are promising alternatives to non-degradable food packaging materials. The films can be utilized for active food packaging applications because CNP exhibits antimicrobial and antioxidant properties, which can improve food shelf-life. Nonetheless, knowledge of the effects of CNP inclusion on the properties of starch films is not fully elucidated. This paper reviews the influences of various concentrations of CNP, sizes of CNP, and other additives on the mechanical, thermal, barrier, antimicrobial, antioxidant, biodegradability, and cytotoxicity properties of starch/CNP films as well as the mechanisms involved in relation to food packaging applications. The usage of starch/CNP films for active food packaging can help to reduce environmental issues and contribute to food safety and security.
    Matched MeSH terms: Antioxidants/pharmacology
  2. Srivastava N, Mishra S, Iqbal H, Chanda D, Shanker K
    J Ethnopharmacol, 2021 May 10;271:113911.
    PMID: 33571614 DOI: 10.1016/j.jep.2021.113911
    ETHNOPHARMACOLOGICAL RELEVANCE: Kaempferia galanga L. rhizome (KGR) is part of more than sixty-one Ayurvedic formulations and commonly known as 'Chandramula'. KGR is widely used in traditional Indian medicines to treat fever (jwar), rheumatism (Amavata), respiratory (Shwasa), hypertension (Vyanabala vaishamya) and cardiovascular disorders (Vyanavayu Dushtijanya Hrudrog). Although ethnomedicinal properties have extensively been demonstrated in traditional medicines of south-east countries i.e. China, India, Indonesia, and Malaysia, the chemico-biological validation are still lacking.

    AIM OF THE STUDY: Chemico-biological standardization with respect to its vasorelaxation potential is the main objective of the present study. To investigate the vasorelaxation potential of key phytochemical of KGR, i.e., ethyl-p-methoxycinnamate (EPMC) and to study it's the mechanism of action.

    MATERIALS AND METHODS: A HPLC method was developed and validated for the quality assessment of KGR using its two major phytochemicals i.e. ethyl-p-methoxycinnamate (EPMC) and ethyl cinnamate (EC) in KGR. The vasorelaxation effect of major phytochemicals of KGR was evaluated on the main mesenteric arteries isolated from male Wistar rats. Specific BKca channel blocker tetraethylammonium (TEA), receptor antagonist, nitric oxide scavenging capacity, and antioxidant potential were also evaluated for its plausible mechanism.

    RESULTS: Present validated HPLC method facilitates simultaneous quantitation of EPMC and EC faster than classical GC techniques. EPMC has shown a dose-dependent relaxation in rat main mesenteric arteries (MMA) contracted by U46619 with an Emax of 58.68 ± 3.31%. Similarly, in endothelium-denuded MMA rings, relaxation was also observed (Emax of 61.83 ± 3.38%). Moreover, relaxation response to EPMC has strongly inhibited (Emax 14.76 ± 2.29%) when the tissue exposed to depolarizing high K+ containing buffer for the contraction. The point correlation dimension (pD2) values were also significantly decreased in high K+ treated arterial rings compared to control. Interestingly, when MMA rings incubated with a specific BKca channel blocker (TEA, 1 mM), the relaxation response to EPMC was also significantly blocked.

    CONCLUSIONS: The first time this study demonstrated the chemical standardization of K. galanga rhizome and EPMC is responsible for its vasorelaxation potential as demonstrated by the endothelium-independent response mediated by Ca2+ dependent potassium channels.

    Matched MeSH terms: Antioxidants/pharmacology
  3. Hussain K, Ismail Z, Sadikun A, Ibrahim P
    Planta Med, 2010 Mar;76(5):418-25.
    PMID: 19862670 DOI: 10.1055/s-0029-1186279
    The present study aimed to investigate standardized ethanol extracts of fruit and leaves of Piper sarmentosum for their in vivo antioxidant activity in rats using a CCl (4)-induced oxidative stress model. The standardization was based on the quantification of the markers pellitorine, sarmentine and sarmentosine by high performance liquid chromatography (HPLC), and determination of total primary and secondary metabolites. The rats, divided into 7 groups each (n = 6), were used as follows: group 1 (CCl (4), negative control), group 2 (untreated, control), groups 3 and 4 (fruit extract 250 and 500 mg/kg, respectively), groups 5 and 6 (leaf extract 250 and 500 mg/kg, respectively) and group 7 (vitamin-E 100 mg/kg, positive control). The doses were administered orally for 14 days; 4 h following the last dose, a single dose of CCl (4) (1.5 mg/kg) was given orally to all the groups except group 2, and after 24 h, blood and liver of each animal were obtained. Analysis of plasma and liver homogenate exhibited significant preservation of markers of antioxidant activity, total plasma antioxidant activity (TPAA), total protein (TP), superoxide dismutase (SOD), catalase (CAT), and thiobarbituric acid reactive species (TBARS), in the pretreated groups as compared to the CCl (4) group (p < 0.05). Histology of the liver also evidenced the protection of hepatocytes against CCl (4) metabolites in the pretreated groups. The results of this study indicate the IN VIVO antioxidant activity of both extracts of the plant, which may be valuable to combat diseases involving free radicals.
    Matched MeSH terms: Antioxidants/pharmacology
  4. El-Boulifi N, Ashari SE, Serrano M, Aracil J, Martínez M
    Enzyme Microb Technol, 2014 Feb 5;55:128-32.
    PMID: 24411455 DOI: 10.1016/j.enzmictec.2013.10.009
    The aim of this work was the synthesis of a novel hydroxyl-fatty acid derivative of kojic acid rich in kojic acid monoricinoleate (KMR) which can be widely used in the cosmetic and food industry. The synthesis of KMR was carried out by lipase-catalysed esterification of ricinoleic and kojic acids in solvent-free system. Three immobilized lipases were tested and the best KMR yields were attained with Lipozyme TL IM and Novozym 435. Since Lipozyme TL IM is the cheapest, it was selected to optimize the reaction conditions. The optimal reaction conditions were 80 °C for the temperature, 1:1 for the alcohol/acid molar ratio, 600 rpm for stirring speed and 7.8% for the catalyst concentration. Under these conditions, the reaction was scaled up in a 5×10⁻³ m³ stirred tank reactor. ¹H-¹³C HMBC-NMR showed that the primary hydroxyl group of kojic acid was regioselectively esterified. The KMR has more lipophilicity than kojic acid and showed antioxidant activity that improves the oxidation stability of biodiesel.
    Matched MeSH terms: Antioxidants/pharmacology
  5. Ghasemzadeh A, Jaafar HZ, Rahmat A, Ashkani S
    BMC Complement Altern Med, 2015 Sep 23;15:335.
    PMID: 26399961 DOI: 10.1186/s12906-015-0838-6
    BACKGROUND: Etlingera elatior is a well-known herb in Malaysia with various pharmaceutical properties.

    METHODS: E. elatior flowers grown in three different locations of Malaysia (Kelantan, Pahang and Johor), were investigated for differences in their content of secondary metabolites (total phenolics [TPC], total flavonoids [TFC], and total tannin content [TTC]) as well as for their antioxidant, anticancer, and antibacterial properties. Phenolic acids and flavonoids were isolated and identified using ultra-high performance liquid chromatography (UHPLC). Ferric reducing antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were used to evaluate the antioxidant activities. The anticancer activity of extracts was evaluated using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay.

    RESULTS: When extracted with various solvents (aqueous and ethanolic), samples from the different locations yielded significantly different results for TPC, TFC, and TTC as well as antioxidant activity. Aqueous extracts of E. elatior flowers collected from Kelantan exhibited the highest values: TPC (618.9 mg/100 g DM), TFC (354.2 mg/100 g DM), TTC (129.5 mg/100 g DM), DPPH (76.4 %), and FRAP (6.88 mM of Fe (II)/g) activity with a half-maximal inhibitory concentration (IC50) of 34.5 μg/mL compared with extracts of flowers collected from the other two locations. The most important phenolic compounds isolated in this study, based on concentration, were: gallic acid > caffeic acid > tannic acid > chlorogenic acid; and the most important flavonoids were: quercetin > apigenin > kaempferol > luteolin > myricetin. Extracts of flowers from Kelantan exhibited potent anticancer activity with a IC50of 173.1 and 196.2 μg/mL against the tumor cell lines MCF-7 and MDA-MB-231 respectively, compared with extracts from Pahang (IC50 = 204.5 and 246.2 μg/mL) and Johor samples (IC50 = 277.1 and 296.7 μg/mL). Extracts of E. elatior flowers also showed antibacterial activities against Staphylococcus aureus, Bacillus subtilis, Listeria monocytogenes, Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa with minimal inhibitory concentrations (MIC) ranging from 30 to >100 μg/mL.

    CONCLUSIONS: In general, therefore, based on the potent antioxidant and anticancer activity of flower extracts, it appears that E. elatior grown in the North-east of Malaysia (Kelantan) is a potential source of therapeutic compounds with anti-cancer activity.

    Matched MeSH terms: Antioxidants/pharmacology
  6. Habsah M, Amran M, Mackeen MM, Lajis NH, Kikuzaki H, Nakatani N, et al.
    J Ethnopharmacol, 2000 Oct;72(3):403-10.
    PMID: 10996279
    Dichloromethane and methanol extracts of 13 Zingiberaceae species from the Alpinia, Costus and Zingiber genera were screened for antimicrobial and antioxidant activities. The antimicrobial activity of most of the extracts was antibacterial with only the methanol extract of Costus discolor showing very potent antifungal activity against only Aspergillus ochraceous (MID, 15.6 microg per disc). All the extracts showed strong antioxidant activity comparable with or higher that of alpha-tocopherol.
    Matched MeSH terms: Antioxidants/pharmacology*
  7. Shen CL, Mo H, Yang S, Wang S, Felton CK, Tomison MD, et al.
    BMJ Open, 2016 12 23;6(12):e012572.
    PMID: 28011809 DOI: 10.1136/bmjopen-2016-012572
    INTRODUCTION: Osteoporosis is a major health concern in postmenopausal women, and oxidative stress contributes to the development of bone loss. Cellular studies and ovariectomised rat model mimicking bone loss in postmenopausal women show the bone-protective effect of tocotrienols (TTs) with antioxidant capability. We aim to access the safety and efficacy of TT consumption for bone health in postmenopausal women.

    METHODS AND ANALYSIS: In this 12-week randomised double-blinded placebo-controlled trial for the effects of dietary TT supplementation in postmenopausal women, postmenopausal women aged 45 years and older with at least 1 year after menopause and bone mineral density T-score at the spine and/or hip 2.5 or more below the reference values will be randomly assigned to 3 daily supplements: (1) placebo group receiving 860 mg olive oil, (2) low TT group receiving 430 mg of 70% pure TTs (containing 300 mg TT) and (3) high TT group receiving 860 mg of 70% pure TTs (600 mg TT). The primary outcome measure will be urinary N-terminal telopeptide. The secondary outcome measures will be serum bone-specific alkaline phosphatase, receptor activator of nuclear factor-κB ligand, osteoprotegerin, urinary 8-hydroxy-2'-deoxyguanosine and quality of life. At 0, 6 and 12 weeks, the following will be assessed: (1) primary and secondary outcome measures; (2) serum TT and tocopherol concentrations; (3) physical activity and food frequency questionnaires. Liver function will be monitored every 6 weeks for safety. 'Intent-to-treat' principle will be employed for data analysis. A model of repeated measurements with random effect error terms will be applied. Analysis of covariance, χ2 analysis and regression will be used for comparisons.

    ETHICS AND DISSEMINATION: This study was approved by the Bioethics Committee of the Texas Tech University Health Sciences Center. The findings of this trial will be submitted to a peer-reviewed journal in the areas of bone or nutrition and international conferences.

    TRIAL REGISTRATION NUMBER: NCT02058420; results.

    Matched MeSH terms: Antioxidants/pharmacology
  8. Aziz NF, Ramalingam A, Latip J, Zainalabidin S
    Life Sci, 2021 Mar 15;269:119080.
    PMID: 33465387 DOI: 10.1016/j.lfs.2021.119080
    S-Allylcysteine (SAC) is an extensively studied natural product which has been proven to confer cardioprotection. This potentiates SAC into many clinical relevance possibilities, hence, the use of it ought to be optimally elucidated. To further confirm this, an ischemia/reperfusion model has been used to determine SAC at 10 mM and 50 mM on cardiac function, cardiac marker, and mitochondrial permeability. Using Langendorff setup, 24 adult male Wistar rats' hearts were isolated to be perfused with Kreb-Henseleit buffer throughout the ischemia/reperfusion method. After 20 min of stabilization, global ischemia was induced by turning off the perfusion for 35 min followed by 60 min of reperfusion with either Kreb-Henseleit buffer or SAC with the dose of 10 mM or 50 mM. The cardiac function was assessed and coronary effluent was collected at different timepoints throughout the experiment for lactate dehydrogenase (LDH) measurement. The harvested hearts were then used to measure glutathione while isolated mitochondria for mPTP analysis. SAC-reperfused hearts were shown to prevent the aggravation of cardiac function after I/R induction. It also dose-dependently upregulated glutathione reductase and glutathione level and these were also accompanied by significant reduction of LDH leakage and preserved mitochondrial permeability. Altogether, SAC dose-dependently was able to recover the post-ischemic cardiac function deterioration alongside with improvement of glutathione metabolism and mitochondrial preservation. These findings highly suggest that SAC when sufficiently supplied to the heart would be able to prevent the deleterious complications after the ischemic insult.
    Matched MeSH terms: Antioxidants/pharmacology*
  9. Magalingam KB, Radhakrishnan A, Haleagrahara N
    Int J Mol Med, 2013 Jul;32(1):235-40.
    PMID: 23670213 DOI: 10.3892/ijmm.2013.1375
    Free radicals are widely known to be the major cause of human diseases such as neurodegenerative diseases, cancer, allergy and autoimmune diseases. Human cells are equipped with a powerful natural antioxidant enzyme network. However, antioxidants, particularly those originating from natural sources such as fruits and vegetables, are still considered essential. Rutin, a quercetin glycoside, has been proven to possess antioxidant potential. However, the neuroprotective effect of rutin in pheochromocytoma (PC-12) cells has not been studied extensively. Therefore, the present study was designed to establish the neuroprotective role of rutin as well as to elucidate the antioxidant mechanism of rutin in 6-hydroxydopamine (6-OHDA)-induced toxicity in PC-12 neuronal cells. PC-12 cells were pretreated with different concentrations of rutin for 4, 8 and 12 h and subsequently incubated with 6-OHDA for 24 h to induce oxidative stress. A significant cytoprotective activity was observed in rutin pretreated cells in a dose-dependent manner. Furthermore, there was marked activation of antioxidant enzymes including superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), and total glutathione (GSH) in rutin pretreated cells compared to cells incubated with 6-OHDA alone. Rutin significantly reduced lipid peroxidation in 6-OHDA-induced PC-12 cells. On the basis of these observations, it was concluded that the bioflavonoid rutin inhibited 6-OHDA-induced neurotoxicity in PC-12 cells by improving antioxidant enzyme levels and inhibiting lipid peroxidation.
    Matched MeSH terms: Antioxidants/pharmacology*
  10. Siti HN, Jalil J, Asmadi AY, Kamisah Y
    Int J Mol Sci, 2021 May 11;22(10).
    PMID: 34064664 DOI: 10.3390/ijms22105063
    Rutin is a flavonoid with antioxidant property. It has been shown to exert cardioprotection against cardiomyocyte hypertrophy. However, studies regarding its antihypertrophic property are still lacking, whether it demonstrates similar antihypertrophic effect to its metabolite, quercetin. Hence, this study aimed to investigate the effects of both flavonoids on oxidative stress and mitogen-activated protein kinase (MAPK) pathway in H9c2 cardiomyocytes that were exposed to angiotensin II (Ang II) to induce hypertrophy. Cardiomyocytes were exposed to Ang II (600 nM) with or without quercetin (331 μM) or rutin (50 μM) for 24 h. A group given vehicle served as the control. The concentration of the flavonoids was chosen based on the reported effective concentration to reduce cell hypertrophy or cardiac injury in H9c2 cells. Exposure to Ang II increased cell surface area, intracellular superoxide anion level, NADPH oxidase and inducible nitric oxide synthase activities, and reduced cellular superoxide dismutase activity and nitrite level, which were similarly reversed by both rutin and quercetin. Rutin had no significant effects on phosphorylated proteins of extracellular signal-related kinases (ERK1/2) and p38 but downregulated phosphorylated c-Jun N-terminal kinases (JNK1/2), which were induced by Ang II. Quercetin, on the other hand, had significantly downregulated the phosphorylated proteins of ERK1/2, p38, and JNK1/2. The quercetin inhibitory effect on JNK1/2 was stronger than the rutin. In conclusion, both flavonoids afford similar protective effects against Ang II-induced cardiomyocyte hypertrophy, but they differently modulate MAPK pathway.
    Matched MeSH terms: Antioxidants/pharmacology
  11. Si LY, Kamisah Y, Ramalingam A, Lim YC, Budin SB, Zainalabidin S
    Appl Physiol Nutr Metab, 2017 Jul;42(7):765-772.
    PMID: 28249121 DOI: 10.1139/apnm-2016-0506
    Vascular endothelial dysfunction (VED) plays an important role in the initiation of cardiovascular diseases. Roselle, enriched with antioxidants, demonstrates high potential in alleviating hypertension. This study was undertaken to investigate the effects of roselle supplementation of VED and remodelling in a rodent model with prolonged nicotine administration. Male Sprague-Dawley rats (n = 6 per group) were administered with 0.6 mg/kg nicotine for 28 days to induce VED. The rats were given either aqueous roselle (100 mg/kg) or normal saline orally 30 min prior to nicotine injection daily. One additional group of rats served as control. Thoracic aorta was isolated from rats to measure vascular reactivity, vascular remodelling and oxidative stress. Roselle significantly lowered aortic sensitivity to phenylephrine-induced vasoconstriction (Endo-(+) Cmax = 234.5 ± 3.9%, Endo-(-) Cmax = 247.6 ± 5.2%) compared with untreated nicotine group (Endo-(+) Cmax = 264.5 ± 6.9%, Endo-(-) Cmax = 276.5 ± 6.8%). Roselle also improved aortic response to endothelium-dependent vasodilator, acetylcholine (Endo-(+) Rmax = 73.2 ± 2.1%, Endo-(-) Rmax = 26.2 ± 0.8%) compared to nicotine group (Endo-(+) Rmax = 57.8 ± 1.7%, Endo-(-) Rmax = 20.9 ± 0.8%). In addition, roselle prevented an increase in intimal media thickness and elastic lamellae proliferation to preserve vascular architecture. Moreover, we also observed a significantly lowered degree of oxidative stress in parallel with increased antioxidant enzymes in aortic tissues of the roselle-treated group. This study demonstrated that roselle prevents VED and remodelling, and as such it has high nutraceutical value as supplement to prevent cardiovascular diseases.
    Matched MeSH terms: Antioxidants/pharmacology
  12. Alharbi KS, Javed Shaikh MA, Imam SS, Alshehri S, Ghoneim MM, Almalki WH, et al.
    Curr Med Chem, 2023;30(18):2061-2074.
    PMID: 36415096 DOI: 10.2174/0929867330666221122115212
    More than 10 million people worldwide have Alzheimer's disease (AD), a degenerative neurological illness and the most prevalent form of dementia. AD's progression in memory loss, cognitive deterioration, and behavioral changes are all symptoms. Amyloid-beta 42 (Aβ42), the hyperphosphorylated forms of microtubule-associated tau protein, and other cellular and systemic alterations are all factors that contribute to cognitive decline in AD. Rather than delivering a possible cure, present therapy strategies focus on reducing disease symptoms. It has long been suggested that various naturally occurring small molecules (plant extract products and microbiological isolates, for example) could be beneficial in preventing or treating disease. Small compounds, such as flavonoids, have attracted much interest recently due to their potential to alleviate cellular stress. Flavonoids have been proven helpful in various ways, including antioxidants, anti-inflammatory agents, and anti-apoptotic agents, but their mechanism remains unknown. The flavonoid therapy of Alzheimer's disease focuses on this review, which includes a comprehensive literature analysis.
    Matched MeSH terms: Antioxidants/pharmacology
  13. Subramanian P, Prasanna V, Jayapalan JJ, Abdul Rahman PS, Hashim OH
    J Insect Physiol, 2014 Jun;65:37-44.
    PMID: 24780191 DOI: 10.1016/j.jinsphys.2014.04.005
    Accruing evidences imply that circadian organization of biochemical, endocrinological, cellular and physiological processes contribute to wellness of organisms and in the development of pathologies such as malignancy, sleep and endocrine disorders. Oxidative stress is known to mediate a number of diseases and it is notable to comprehend the orchestration of circadian clock of a model organism of circadian biology, Drosophila melanogaster, under oxidative stress. We investigated the nexus between circadian clock and oxidative stress susceptibility by exposing D. melanogaster to hydrogen peroxide (H2O2) or rotenone; the reversibility of rhythms following exposure to Bacopa monnieri extract (ayurvedic medicine rich in antioxidants) was also investigated. Abolishment of 24h rhythms in physiological response (negative geotaxis), oxidative stress markers (protein carbonyl and thiobarbituric acid reactive substances) and antioxidants (superoxide dismutase, catalase, glutathione-S-transferase and reduced glutathione) were observed under oxidative stress. Furthermore, abolishment of per mRNA rhythm in H2O2 treated wild type flies and augmented susceptibility to oxidative stress in clock mutant (cry(b)) flies connotes the role of circadian clock in reactive oxygen species (ROS) homeostasis. Significant reversibility of rhythms was noted following B. monnieri treatment in wild type flies than cry(b) flies. Our experimental approach revealed a relationship involving oxidative stress and circadian clock in fruit fly and the utility of Drosophila model in screening putative antioxidative phytomedicines prior to their use in mammalian systems.
    Matched MeSH terms: Antioxidants/pharmacology*
  14. Shahzad S, Batool Z, Afzal A, Haider S
    Metab Brain Dis, 2022 Dec;37(8):2793-2805.
    PMID: 36152087 DOI: 10.1007/s11011-022-01090-6
    Quercetin, a polyphenolic compound found in a variety of plant products possesses various biological activities and beneficial effects on human health. Schizophrenia (SZ) is one of the neuropsychiatric disorders in human beings with rapid mortality and intense morbidity which can be treated with antipsychotics, but these commercial drugs exert adverse effects and have less efficacy to treat the full spectrum of SZ. The present study was conducted to evaluate neuroprotective effects of quercetin in the preventive and therapeutic treatment of SZ. Quercetin was administered as pre- and post-regimens at the dose of 50 mg/kg in dizocilpine-induced SZ rat model for two weeks. Rats were then subjected for the assessment of different behaviors followed by biochemical, neurochemical, and inflammatory marker analyses. The present findings revealed that quercetin significantly reverses the effects of dizocilpine-induced psychosis-like symptoms in all behavioral assessments as well as it also combats oxidative stress. This flavonoid also regulates dopaminergic, serotonergic, and glutamatergic neurotransmission. A profound effect on inflammatory cytokines and decreased %DNA fragmentation was also observed following the administration of quercetin. The findings suggest that quercetin can be considered as a preventive as well as therapeutic strategy to attenuate oxidative stress and cytokine toxicity, regulate neurotransmission, and prevent enhanced DNA fragmentation that can lead to the amelioration of psychosis-like symptoms in SZ.
    Matched MeSH terms: Antioxidants/pharmacology
  15. Bahari AN, Saari N, Salim N, Ashari SE
    Molecules, 2020 Jun 08;25(11).
    PMID: 32521731 DOI: 10.3390/molecules25112663
    Actinopyga lecanora (A. lecanora) is classified among the edible species of sea cucumber, known to be rich in protein. Its hydrolysates were reported to contain relatively high antioxidant activity. Antioxidants are one of the essential properties in cosmeceutical products especially to alleviate skin aging. In the present study, pH, reaction temperature, reaction time and enzyme/substrate ratio (E/S) have been identified as the parameters in the papain enzymatic hydrolysis of A. lecanora. The degree of hydrolysis (DH) with antioxidant activities of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP) assays were used as the responses in the optimization. Analysis of variance (ANOVA), normal plot of residuals and 3D contour plots were evaluated to study the effects and interactions between parameters. The best conditions selected from the optimization were at pH 5.00, 70 °C of reaction temperature, 9 h of hydrolysis time and 1.00% enzyme/substrate (E/S) ratio, with the hydrolysates having 51.90% of DH, 42.70% of DPPH activity and 109.90 Fe2+μg/mL of FRAP activity. The A. lecanora hydrolysates (ALH) showed a high amount of hydrophobic amino acids (286.40 mg/g sample) that might be responsible for antioxidant and antityrosinase activities. Scanning electron microscopy (SEM) image of ALH shows smooth structures with pores. Antityrosinase activity of ALH exhibited inhibition of 31.50% for L-tyrosine substrate and 25.40% for L-DOPA substrate. This condition suggests that the optimized ALH acquired has the potential to be used as a bioactive ingredient for cosmeceutical applications.
    Matched MeSH terms: Antioxidants/pharmacology*
  16. Mediani A, Abas F, Khatib A, Tan CP, Ismail IS, Shaari K, et al.
    Plant Foods Hum Nutr, 2015 Jun;70(2):184-92.
    PMID: 25800644 DOI: 10.1007/s11130-015-0478-5
    The study investigated the changes in the metabolite, antioxidant and α-glucosidase inhibitory activities of Phyllanthus niruri after three drying treatments: air, freeze and oven dryings. Water extracts and extracts obtained using different solvent ratios of ethanol and methanol (50, 70, 80 and 100%) were compared. The relationships among the antioxidant, α-glucosidase inhibitory activity and metabolite levels of the extracts were evaluated using partial least-square analysis (PLS). The solvent selectivity was assessed based on the phytochemical constituents present in the extract and their concentrations quantitatively analyzed using high performance liquid chromatography. The freeze-dried P. niruri samples that were extracted with the mixture of ethanol or methanol with low ratio of water showed higher biological activity values compared with the other extracts. The PLS results for the ethanolic with different ratio and water extracts demonstrated that phenolic acids (chlorogenic acid and ellagic acid) and flavonoids were highly linked to strong α-glucosidase inhibitory and antioxidant activities.
    Matched MeSH terms: Antioxidants/pharmacology*
  17. Abdul Nasir NA, Agarwal R, Sheikh Abdul Kadir SH, Vasudevan S, Tripathy M, Iezhitsa I, et al.
    PLoS One, 2017;12(3):e0174542.
    PMID: 28350848 DOI: 10.1371/journal.pone.0174542
    Cataract, a leading cause of blindness, is of special concern in diabetics as it occurs at earlier onset. Polyol accumulation and increased oxidative-nitrosative stress in cataractogenesis are associated with NFκB activation, iNOS expression, ATP depletion, loss of ATPase functions, calpain activation and proteolysis of soluble to insoluble proteins. Tocotrienol was previously shown to reduce lens oxidative stress and inhibit cataractogenesis in galactose-fed rats. In current study, we investigated anticataract effects of topical tocotrienol and possible mechanisms involved in streptozotocin-induced diabetic rats. Diabetes was induced in Sprague Dawley rats by intraperitoneal injection of streptozotocin. Diabetic rats were treated with vehicle (DV) or tocotrienol (DT). A third group consists of normal, non-diabetic rats were treated with vehicle (NV). All treatments were given topically, bilaterally, twice daily for 8 weeks with weekly slit lamp monitoring. Subsequently, rats were euthanized and lenses were subjected to estimation of polyol accumulation, oxidative-nitrosative stress, NFκB activation, iNOS expression, ATP levels, ATPase activities, calpain activity and total protein levels. Cataract progression was delayed from the fifth week onwards in DT with lower mean of cataract stages compared to DV group (p<0.01) despite persistent hyperglycemia. Reduced cataractogenesis in DT group was accompanied with lower aldose reductase activity and sorbitol level compared to DV group (p<0.01). DT group also showed reduced NFκB activation, lower iNOS expression and reduced oxidative-nitrosative stress compared to DV group. Lenticular ATP and ATPase and calpain 2 activities in DT group were restored to normal. Consequently, soluble to insoluble protein ratio in DT group was higher compared to DV (p<0.05). In conclusion, preventive effect of topical tocotrienol on development of cataract in STZ-induced diabetic rats could be attributed to reduced lens aldose reductase activity, polyol levels and oxidative-nitrosative stress. These effects of tocotrienol invlove reduced NFκB activation, lower iNOS expression, restoration of ATP level, ATPase activities, calpain activity and lens protein levels.
    Matched MeSH terms: Antioxidants/pharmacology
  18. Chin SF, Hamid NA, Latiff AA, Zakaria Z, Mazlan M, Yusof YA, et al.
    Nutrition, 2008 Jan;24(1):1-10.
    PMID: 17884341
    The free radical theory of aging (FRTA) suggests that free radicals are the leading cause of deteriorating physiologic function during senescence. Free radicals attack cellular structures or molecules such as DNA resulting in various modifications to the DNA structures. Accumulation of unrepaired DNA contributes to a variety of disorders associated with the aging process.
    Matched MeSH terms: Antioxidants/pharmacology*
  19. Uthaya Kumar US, Chen Y, Kanwar JR, Sasidharan S
    Oxid Med Cell Longev, 2016;2016:6841348.
    PMID: 28053693 DOI: 10.1155/2016/6841348
    The therapeutic potential of Cassia surattensis in reducing free radical-induced oxidative stress and inflammation particularly in hepatic diseases was evaluated in this study. The polyphenol rich C. surattensis seed extract showed good in vitro antioxidant. C. surattensis seed extract contained total phenolic content of 100.99 mg GAE/g dry weight and there was a positive correlation (r > 0.9) between total phenolic content and the antioxidant activities of the seed extract. C. surattensis seed extract significantly (p < 0.05) reduced the elevated levels of serum liver enzymes (ALT, AST, and ALP) and relative liver weight in paracetamol-induced liver hepatotoxicity in mice. Moreover, the extract significantly (p < 0.05) enhanced the antioxidant enzymes and glutathione (GSH) contents in the liver tissues, which led to decrease of malondialdehyde (MDA) level. The histopathological examination showed the liver protective effect of C. surattensis seed extract against paracetamol-induced histoarchitectural alterations by maximum recovery in the histoarchitecture of the liver tissue. Furthermore, histopathological observations correspondingly supported the biochemical assay outcome, that is, the significant reduction in elevated levels of serum liver enzymes. In conclusion, C. surattensis seed extract enhanced the in vivo antioxidant status and showed antihepatotoxic activities, which is probably due to the presence of phenolic compounds.
    Matched MeSH terms: Antioxidants/pharmacology*
  20. Yehye WA, Abdul Rahman N, Saad O, Ariffin A, Abd Hamid SB, Alhadi AA, et al.
    Molecules, 2016 Jun 28;21(7).
    PMID: 27367658 DOI: 10.3390/molecules21070847
    A new series of multipotent antioxidants (MPAOs), namely Schiff base-1,2,4-triazoles attached to the oxygen-derived free radical scavenging moiety butylated hydroxytoluene (BHT) were designed and subsequently synthesized. The structure-activity relationship (SAR) of the designed antioxidants was established alongside the prediction of activity spectra for substances (PASS). The antioxidant activities of the synthesized compounds 4-10 were tested by the DPPH bioassay. The synthesized compounds 4-10 inhibited stable DPPH free radicals at a level that is 10(-4) M more than the well-known standard antioxidant BHT. Compounds 8-10 with para-substituents were less active than compounds 4 and 5 with trimethoxy substituents compared to those with a second BHT moiety (compounds 6 and 7). With an IC50 of 46.13 ± 0.31 µM, compound 6 exhibited the most promising in vitro inhibition at 89%. Therefore, novel MPAOs containing active triazole rings, thioethers, Schiff bases, and BHT moieties are suggested as potential antioxidants for inhibiting oxidative stress processes and scavenging free radicals, hence, this combination of functions is anticipated to play a vital role in repairing cellular damage, preventing various human diseases and in medical therapeutic applications.
    Matched MeSH terms: Antioxidants/pharmacology*
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