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Fulltext Tocotrienol-Rich Fraction Ameliorates Antioxidant Defense Mechanisms and Improves Replicative Senescence-Associated Oxidative Stress in Human Myoblasts

Khor SC, Wan Ngah WZ, Mohd Yusof YA, Abdul Karim N, Makpol S

Oxid Med Cell Longev, 2017;2017:3868305.
PMID: 28243354 DOI: 10.1155/2017/3868305

During aging, oxidative stress affects the normal function of satellite cells, with consequent regeneration defects that lead to sarcopenia. This study aimed to evaluate tocotrienol-rich fraction (TRF) modulation in reestablishing the oxidative status of myoblasts during replicative senescence and to compare the effects of TRF with other antioxidants (α-tocopherol (ATF) and N-acetyl-cysteine (NAC)). Primary human myoblasts were cultured to young, presenescent, and senescent phases. The cells were treated with antioxidants for 24 h, followed by the assessment of free radical generation, lipid peroxidation, antioxidant enzyme mRNA expression and activities, and the ratio of reduced to oxidized glutathione. Our data showed that replicative senescence increased reactive oxygen species (ROS) generation and lipid peroxidation in myoblasts. Treatment with TRF significantly diminished ROS production and decreased lipid peroxidation in senescent myoblasts. Moreover, the gene expression of superoxide dismutase (SOD2), catalase (CAT), and glutathione peroxidase (GPX1) was modulated by TRF treatment, with increased activity of superoxide dismutase and catalase and reduced glutathione peroxidase in senescent myoblasts. In comparison to ATF and NAC, TRF was more efficient in heightening the antioxidant capacity and reducing free radical insults. These results suggested that TRF is able to ameliorate antioxidant defense mechanisms and improves replicative senescence-associated oxidative stress in myoblasts.

Matched MeSH terms: Free Radicals/metabolism
Fulltext Fatigue onset through oxidative stress, dehydration and lactic acid accumulation and its in vivo study using experimental animals

Hani Hafeeza Halim, Mohd Sabri Pak Dek, Azizah Abdul Hamid, Ahmad Haniff Jaafar

Journal of Advanced Review on Scientific Research, 2017;35(1):1-12.
MyJurnal

Among athletes, endurance is one of the key elements to victory. In addition to
training, athletes normally used supplement to prevent fatigue during the event. With
prolonged and intense activity, our body started to experience decrease in muscle
performance due to several factors such as oxidative stress, dehydration and
accumulation of lactic acid in the body fluids. The free radicals generated during
intense exercise will expose the cells to oxidative damages. In the event of
dehydration, there will be significant losses of water and functional electrolytes during
intense exercise which affected the body fluid balance. Fatigue will also occur during
reduced oxygen in aerobic metabolism which later caused accumulation of lactic acid
in the muscle. This will change the pH balance toward more acidic and caused the
muscles to lose contractile efficiency. In addition, fatigue can also be studied using rats
as model organism. Results from this activity can be useful to analyse cellular
metabolism and physiology effects of the tested rats toward physical exercise.
Therefore, this review aims to discuss the causes of fatigue through oxidative stress,
dehydration and lactic acid accumulation. In addition, the effectiveness of using rats as
a model system in measuring fatigue is also included in illustrating examples on fatigue
assessment in vivo.

Matched MeSH terms: Free Radicals
Fulltext Total phenolic content and antioxidant capacity of Basil (Ocimum Basilicum L.) leaves from different locations

Aburigal, Y.A.A., Mirghani, M.E.S., Elmogtaba, E.Y., Sirible, A.A.M., Hamza, N.B., Hussein, I.H.

International Food Research Journal, 2017;24(101):0-0.
MyJurnal

The present study was carried out to determine the antioxidant activity and total phenolic content of Ocimum basilicum collected from different regions of the world. The accession V1 is from Sudan, V2 from Iraq, V3 from Germany, V4 from Thailand, V5 from Russia and V6 from Maldives. The extracts from six basil accessions were analysed for their DPPH free radical scavenging activity and their total phenolic content (TPC). The results suggest that the highest antioxidant activity was found in V6 (from Maldives) and the lowest antioxidant activity was found in V4 (from Thailand). The highest amount of phenolic content was found in V6 (from Maldives) and the lowest phenolic content was found inV4 (from Thailand). This study shows that basil is a good source of free-radical scavenging compounds that have their traditional medicinal applications.

Matched MeSH terms: Free Radicals
Preparation of methacrylamide-functionalized crosslinked chitosan by free radical polymerization for the removal of lead ions

Sutirman ZA, Sanagi MM, Abd Karim KJ, Wan Ibrahim WA

Carbohydr Polym, 2016 Oct 20;151:1091-1099.
PMID: 27474659 DOI: 10.1016/j.carbpol.2016.06.076

A new poly(methacrylamide) grafted crosslinked chitosan was prepared for removal of lead, Pb(II) ion from aqueous solution. Crosslinked chitosan, in beads form, was grafted with methacrylamide (MAm) using ammonium persulfate (APS) as free radical initiator. Evidence of grafting was determined by comparing FTIR, TGA, SEM and (13)C NMR analyses of chitosan and graft copolymer. The optimal conditions for grafting reaction were as follow: crosslinked chitosan beads (1g), MAm (17.62×10(-1)M), APS (2.63×10(-1)M), reaction time (3h) and temperature (60°C). The modified chitosan bead was then used in laboratory batch experiments to evaluate the removal of Pb(II) ion from water samples. The Langmuir and Freundlich adsorption models were also applied to describe the equilibrium isotherms. The results revealed that the adsorption of Pb(II) ions onto the beads fitted very well with the Langmuir model with the maximum capacity (qmax) of 250mgg(-1).

Matched MeSH terms: Free Radicals/chemistry
Biological Activities of Isolated Compounds from Three Edible Malaysian Red Seaweeds, Gracilaria changii, G. manilaensis and Gracilaria sp

Andriani Y, Syamsumir DF, Yee TC, Harisson FS, Herng GM, Abdullah SA, et al.

Nat Prod Commun, 2016 Aug;11(8):1117-1120.
PMID: 30725572

Gracilaria species are red marine macroalgae that are found abundantly in Malaysia. Gracilaria changii from Morib, Selangor, G. nanilaensis and Gracilaria sp. from Gelang Patah, Johor were used in this study. Five compounds were successfully isolated and identified as hexadecanoic acid (1), cholest-5-en-3-ol (2), 2-hydroxymyristic acid (3), cholesteryl myristate (4) and 1-(4'-methoxyphenyl)-3-(2",4",6"-trihydroxyphenyl)-3-hydroxypropanone (5) based on spectral data analysis (IR, UV, GC-MS, 'H NMR, "C NMR, HMQC and HMBC). All compounds isolated were tested for cytotoxicity (MTT assay for HL-60 and MCF-7 cell lines), and antibacterial (disc diffusion method), antioxidant (DPPH free radical scavenging assay and xanthine oxidase inhibitory assay) and acetylcholinesterase inhibitory (AChE) activity (TLC bioautographic method). Compounds I and 3 exhibited strong cytotoxic activity against HL-60 and MCF-7 cell lines. Compound 5 showed high antioxidant activity in both the DPPH free radical scavenging and xanthine oxidase inhibition assays. Compound I showed positive activity for AChE inhibitory with a minimum inhibition dose of 0.625 tg sample. All compounds demonstrated antibacterial activity producing 8 to 14 mm inhibition zones. A positive control was applied to all bioassays and experiments were performed with three replicates. Results demonstrated that three edible red seaweeds are rich sources of bioactive compounds with potential application for pharmaceutical purposes.

Matched MeSH terms: Free Radicals
Fulltext Rational Design and Synthesis of New, High Efficiency, Multipotent Schiff Base-1,2,4-triazole Antioxidants Bearing Butylated Hydroxytoluene Moieties

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: Free Radicals/antagonists & inhibitors; Free Radicals/chemistry
Fulltext Sundarban Honey Confers Protection against Isoproterenol-Induced Myocardial Infarction in Wistar Rats

Afroz R, Tanvir EM, Karim N, Hossain MS, Alam N, Gan SH, et al.

Biomed Res Int, 2016;2016:6437641.
PMID: 27294126 DOI: 10.1155/2016/6437641

The present study was designed to investigate the cardioprotective effects of Sundarban honey (SH) in rats with isoproterenol- (ISO-) induced myocardial infarction. Adult male Wistar Albino rats were pretreated with Sundarban honey (5 g/kg) daily for a period of 6 weeks. After the treatment period, ISO (85 mg/kg) was subcutaneously injected into the rats at 24 h intervals for 2 days. ISO-induced myocardial damage was indicated by increased serum cardiac specific troponin I levels and cardiac marker enzyme activities including creatine kinase-MB, lactate dehydrogenase, aspartate transaminase, and alanine transaminase. Significant increases in serum total cholesterol, triglycerides, and low-density lipoprotein-cholesterol levels were also observed, along with a reduction in the serum high-density lipoprotein-cholesterol level. In addition to these diagnostic markers, the levels of lipid peroxide products were significantly increased. The activities of antioxidant enzymes such as superoxide dismutase, glutathione peroxidase, and glutathione reductase were significantly decreased in the hearts after ISO-induced myocardial infarction. However, pretreatment of ischemic rats with Sundarban honey brought the biochemical parameters to near normalcy, indicating the protective effect of Sundarban honey against ISO-induced ischemia in rats. Histopathological findings of the heart tissues further confirmed the biochemical findings, indicating that Sundarban honey confers protection against ISO-induced oxidative stress in the myocardium.

Matched MeSH terms: Free Radicals
Fulltext The Tocotrienol-Rich Fraction Is Superior to Tocopherol in Promoting Myogenic Differentiation in the Prevention of Replicative Senescence of Myoblasts

Khor SC, Razak AM, Wan Ngah WZ, Mohd Yusof YA, Abdul Karim N, Makpol S

PLoS One, 2016;11(2):e0149265.
PMID: 26885980 DOI: 10.1371/journal.pone.0149265

Aging results in a loss of muscle mass and strength. Myoblasts play an important role in maintaining muscle mass through regenerative processes, which are impaired during aging. Vitamin E potentially ameliorates age-related phenotypes. Hence, this study aimed to determine the effects of the tocotrienol-rich fraction (TRF) and α-tocopherol (ATF) in protecting myoblasts from replicative senescence and promoting myogenic differentiation. Primary human myoblasts were cultured into young and senescent stages and were then treated with TRF or ATF for 24 h, followed by an analysis of cell proliferation, senescence biomarkers, cellular morphology and differentiation. Our data showed that replicative senescence impaired the normal regenerative processes of myoblasts, resulting in changes in cellular morphology, cell proliferation, senescence-associated β-galactosidase (SA-β-gal) expression, myogenic differentiation and myogenic regulatory factors (MRFs) expression. Treatment with both TRF and ATF was beneficial to senescent myoblasts in reclaiming the morphology of young cells, improved cell viability and decreased SA-β-gal expression. However, only TRF treatment increased BrdU incorporation in senescent myoblasts, as well as promoted myogenic differentiation through the modulation of MRFs at the mRNA and protein levels. MYOD1 and MYOG gene expression and myogenin protein expression were modulated in the early phases of myogenic differentiation. In conclusion, the tocotrienol-rich fraction is superior to α-tocopherol in ameliorating replicative senescence-related aberration and promoting differentiation via modulation of MRFs expression, indicating vitamin E potential in modulating replicative senescence of myoblasts.

Matched MeSH terms: Free Radicals/metabolism
Fulltext In vitro antioxidant capacities and antidiabetic properties of phenolic extracts from selected citrus peels

Lim, S.M., Loh, S.P.

International Food Research Journal, 2016;23(1):211-219.
MyJurnal

This study aims to determine the antioxidant capacities (AC) and antidiabetic properties of
phenolic extracts (free and bound) from white Tambun pomelo peels, kaffir lime peels, lime
peels and calamansi peels. AC, total phenolic content (TPC) and antidiabetic properties of
selected citrus peels extracts were determined spectrophotometrically using 2,2-Diphenyl-1-
picrylhydrazyl free radical (DPPH) scavenging, ferric-reducing antioxidant power (FRAP),
Folin-Ciocalteu (FC) and α-amylase and α-glucosidase inhibition assay, respectively. This
study found that the methanolic extract of kaffir lime showed the best AC with the lowest
IC50 value of DPPH radical (7.51 ± 0.50 mg/ml) and highest FRAP value [369.48 ± 20.15
mM Fe (II) E/g DW]. TPC of free phenolic extracts of all citrus peels were significantly (p<
0.05) higher compared to the bound phenolic extracts with extract of calamansi showed the
highest TPC. Free- and bound phenolic extract of calamansi also had the highest α-amylase
inhibition activity (61.79 ± 4.13%; 45.30 ± 5.35%) respectively. The highest inhibitory effect in
α-glucosidase inhibition assay of free- and bound phenolic extracts were white Tambun pomelo
(41.06 ± 10.94%) and calamansi (43.99 ± 22.03%) respectively. Hence, the citrus peels could
be furthered study for their potential in management and/or prevention of diabetes.

Matched MeSH terms: Free Radicals
Fulltext Comparison of Dill Seed Oil Mouth Rinse and Chlorhexidine Mouth Rinse on Plaque Levels and Gingivitis - A Double Blind Randomized Clinical Trial

Eshwar S, K R, Jain V, Manvi S, Kohli S, Bhatia S

Open Dent J, 2016;10:207-13.
PMID: 27386006 DOI: 10.2174/1874210601610010207

INTRODUCTION: Mouthrinses have been in use for centuries as breath fresheners, medicaments, and antiseptics. Dill is said to be a good source of calcium, manganese and iron. It contains flavonoids known for their antioxidant, anti-inflammatory, and antiviral properties. Dill can help with microbial infections in the mouth; and its anti-oxidants minimize damage caused by free radicals to the gums and teeth. Being a good source of calcium, dill also helps with bone and dental health.
AIMS AND OBJECTIVES: To compare the effectiveness of commercially available 0.2% chlorhexidine gluconate mouthrinse and dill seed oil mouthrinse on plaque levels and gingivitis.
MATERIAL AND METHODS: A randomized controlled, double blind parallel arm study was conducted over 90 days on 90 subjects. The subjects were randomly divided into 2 groups and baseline data was collected using Loe and Silness gingival index and Quigley Hein plaque index and oral prophylaxis was performed on all the subjects. The mouthrinses included in the present study were dill seed oil and Hexodent (0.2% chlorhexidine gluconate). Intervention regarding the mouthrinsing was given to the subjects and were followed up for 45 days and 90 days, after this post intervention changes were assessed using the respective indices.
RESULTS: It was observed that there is no significant difference in gingival & plaque scores among two mouthrinses from baseline to 45 days and 90 days. It was observed that there is statistical difference in gingival and plaque scores when compared with baseline to 45 days (p<0.001), baseline to 90 days (p<0.001) and 45 days to 90 days (p<0.001) when intergroup comparisons were done.
CONCLUSION: It was concluded that dill seed oil and Hexodent (0.2% chlorhexidine gluconate) mouthrinse have similar antiplaque and antigingival effectiveness.

Matched MeSH terms: Free Radicals
Dietary UKMR-1 roselle supplementation prevents nicotine-induced cardiac injury by inhibiting myocardial oxidative stress

Ramalingam A, Siti Balkis Budin, Lim Yc, Lislivia Si Yn, Satirah Zainalabidin

Sains Malaysiana, 2016;45:1131-1137.

UKMR-1, a local variant of mutant Roselle strain (Hibiscus sabdariffa) is enriched with free radical scavenging polyphenols
such as anthocyanin, vitamin C and hydroxycitric acid. However, pharmacological actions of UKMR-1 are not fully known.
This study was conducted to determine whether supplementation of aqueous UKMR-1 calyx extract was able to protect
against nicotine-induced cardiac injury in rats. In this experimental study, healthy male albino rats were randomly
allotted into three groups (n=7 per group): control, nicotine and UKMR-1+Nicotine groups. Nicotine (0.6 mg/kg, i.p.)
was administered to both nicotine and UKMR-1+Nicotine groups for 28 consecutive days. UKMR-1+Nicotine group also
received 100 mg/kg UKMR-1 extract orally via gavage 30 min prior to nicotine injection, daily. UKMR-1+Nicotine group
had significantly (p<0.05) higher lactate dehydrogenase (LDH) activity, as well as lower malondialdehyde content in
heart tissue homogenate than nicotine group, suggesting its cardio protective activity by inhibition of lipid peroxidation.
UKMR-1 also lowered (p<0.05) the blood pressure in nicotine-administered rats. In addition, UKMR-1 significantly (p<0.05)
restored activities of cytosolic superoxide dismutase, glutathione peroxidase and glutathione-S-transferase as well as
redox balance ratio (GSH:GSSG). In conclusion, UKMR-1 was a

Matched MeSH terms: Free Radicals
Fulltext Phytochemicals and Medicinal Properties of Indigenous Tropical Fruits with Potential for Commercial Development

Khoo HE, Azlan A, Kong KW, Ismail A

Evid Based Complement Alternat Med, 2016;2016:7591951.
PMID: 27340420 DOI: 10.1155/2016/7591951

Hundreds of fruit-bearing trees are native to Southeast Asia, but many of them are considered as indigenous or underutilized. These species can be categorized as indigenous tropical fruits with potential for commercial development and those possible for commercial development. Many of these fruits are considered as underutilized unless the commercialization is being realized despite the fact that they have the developmental potential. This review discusses seven indigenous tropical fruits from 15 species that have been identified, in which their fruits are having potential for commercial development. As they are not as popular as the commercially available fruits, limited information is found. This paper is the first initiative to provide information on the phytochemicals and potential medicinal uses of these fruits. Phytochemicals detected in these fruits are mainly the phenolic compounds, carotenoids, and other terpenoids. Most of these phytochemicals are potent antioxidants and have corresponded to the free radical scavenging activities and other biological activities of the fruits. The scientific research that covered a broad range of in vitro to in vivo studies on the medicinal potentials of these fruits is also discussed in detail. The current review is an update for researchers to have a better understanding of the species, which simultaneously can provide awareness to enhance their commercial value and promote their utilization for better biodiversity conservation.

Matched MeSH terms: Free Radicals
Synthesis and characterization of silver nanoparticles using fruit extract of Momordica cymbalaria and assessment of their in vitro antimicrobial, antioxidant and cytotoxicity activities

Swamy MK, Akhtar MS, Mohanty SK, Sinniah UR

Spectrochim Acta A Mol Biomol Spectrosc, 2015 Dec 5;151:939-44.
PMID: 26186612 DOI: 10.1016/j.saa.2015.07.009

Plant mediated synthesis of nanoparticles has been considered as green route and a reliable technique for the synthesis of nanoparticles due to its eco-friendly approach. In this study, we report a simple and eco-friendly approach for the synthesis of silver nanoparticles (AgNPs) using methanolic Momordica cymbalaria fruit extract as reducing agent. The fruit extract of M. cymbalaria exposed to AgNO3 solution showed the change in color from green to light yellow at room temperature within 1h of incubation confirms the synthesis of AgNPs. UV-vis spectra analysis revealed that the synthesized AgNPs had a sharp surface plasmon resonance at around 450 nm, while, the X-ray Diffraction (XRD) patterns confirmed distinctive peaks indices to the crystalline planes of the face centered cubic silver. The Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) analysis results confirmed the presence of spherical shaped AgNPs by a huge disparity in the particle size distribution with an average size of 15.5 nm. The synthesized AgNPs showed strong antibacterial activity against all the tested multidrug resistant human pathogenic bacterial strains and also exhibited highest free radical scavenging activity (74.2%) compared to fruit extract (60.4%). Moreover, both fruit extract and the synthesized AgNPs showed the cytotoxicity towards Rat L6 skeletal muscle cell line at different concentrations, but the highest inhibition percentage was recorded for AgNPs at concentration of 100 μg/ml.

Matched MeSH terms: Free Radicals
Fulltext Thermal and UV Hydrosilylation of Alcohol-Based Bifunctional Alkynes on Si (111) surfaces: How surface radicals influence surface bond formation

Khung YL, Ngalim SH, Scaccabarozi A, Narducci D

Sci Rep, 2015 Jun 12;5:11299.
PMID: 26067470 DOI: 10.1038/srep11299

Using two different hydrosilylation methods, low temperature thermal and UV initiation, silicon (111) hydrogenated surfaces were functionalized in presence of an OH-terminated alkyne, a CF3-terminated alkyne and a mixed equimolar ratio of the two alkynes. XPS studies revealed that in the absence of premeditated surface radical through low temperature hydrosilylation, the surface grafting proceeded to form a Si-O-C linkage via nucleophilic reaction through the OH group of the alkyne. This led to a small increase in surface roughness as well as an increase in hydrophobicity and this effect was attributed to the surficial etching of silicon to form nanosize pores (~1-3 nm) by residual water/oxygen as a result of changes to surface polarity from the grafting. Furthermore in the radical-free thermal environment, a mix in equimolar of these two short alkynes can achieve a high contact angle of ~102°, comparable to long alkyl chains grafting reported in literature although surface roughness was relatively mild (rms = ~1 nm). On the other hand, UV initiation on silicon totally reversed the chemical linkages to predominantly Si-C without further compromising the surface roughness, highlighting the importance of surface radicals determining the reactivity of the silicon surface to the selected alkynes.

Matched MeSH terms: Free Radicals
Fulltext Influence of customized cooking methods on the phenolic contents and antioxidant activities of selected species of oyster mushrooms (Pleurotus spp.)

Tan YS, Baskaran A, Nallathamby N, Chua KH, Kuppusamy UR, Sabaratnam V

J Food Sci Technol, 2015 May;52(5):3058-64.
PMID: 25892809 DOI: 10.1007/s13197-014-1332-8

Nutritional value of cooked food has been considered to be lower compared to the fresh produce. However, many reports showed that processed fruits and vegetables including mushrooms may retain antioxidant activity. Pleurotus spp. as one of the edible mushroom are in great demand globally and become one of the most popular mushrooms grown worldwide with 25-fold increase in production from 1960-2009. The effects of three different cooking methods (boiling, microwave and pressure cooking) on the antioxidant activities of six different types of oyster mushrooms (Pleurotus eryngii, P citrinopileatus, P. cystidiosus P. flabellatus, P. floridanus and P. pulmonarius) were assessed. Free radical scavenging (DPPH) and reducing power (TEAC) were used to evaluate the antioxidant activities and the total phenolic contents were determined by Folin-Ciocalteu reagent. Pressure cooking improved the scavenging abilities of P. floridanus (>200 %), P. flabellatus (117.6 %), and P. pulmonarius (49.1 %) compared to the uncooked samples. On the other hand, the microwaved Pleurotus eryngii showed 17 % higher in the TEAC value when compared to the uncooked sample. There was, however, no correlation between total phenolic content and antioxidant activities. There could be presence of other bioactive components in the processed mushrooms that may have contributed to the antioxidant activity. These results suggested that customized cooking method can be used to enhance the nutritional value of mushrooms and promote good health.

Matched MeSH terms: Free Radicals
Fulltext Production of Nanoemulsions from Palm-Based Tocotrienol Rich Fraction by Microfluidization

Goh PS, Ng MH, Choo YM, Amru NB, Chuah CH

Molecules, 2015;20(11):19936-46.
PMID: 26556328 DOI: 10.3390/molecules201119666

In the present study, tocotrienol rich fraction (TRF) nanoemulsions were produced as an alternative approach to improve solubility and absorption of tocotrienols. In the present study, droplet size obtained after 10 cycles of homogenization with increasing pressure was found to decrease from 120 to 65.1 nm. Nanoemulsions stabilized with Tween series alone or emulsifier blend Brij 35:Span 80 (0.6:0.4 w/w) homogenized at 25,000 psi and 10 cycles, produced droplet size less than 100 nm and a narrow size distribution with a polydispersity index (PDI) value lower than 0.2. However blend of Tween series with Span 80 produced nanoemulsions with droplet size larger than 200 nm. This work has also demonstrated the amount of tocols losses in TRF nanoemulsion stabilized Tweens alone or emulsifier blend Brij 35:Span 80 (0.6:0.4 w/w) ranged between 3%-25%. This can be attributed to the interfacial film formed surrounding the droplets exhibited different level of oxidative stability against heat and free radicals created during high pressure emulsification.

Matched MeSH terms: Free Radicals
Fulltext Antioxidative and acetylcholinesterase inhibitor potential of selected honey of Sabah, Malaysian Borneo

Philip, Y., Mohd Fadzelly, A. B.

International Food Research Journal, 2015;22(5):1953-1960.
MyJurnal

Honey is a sweet substance that can be obtain from flower nectar and secretes through transformations process by honey bees. The aim of this study was to compare the antioxidant and anti-cholinesterase activities of 4 wild honey (wild honey produced by different species of bees: Apis cerana, Apis andreniformis, Apis koschevnikovi and Apis nuluensis) collected from the secondary forest and 6 commercial (young and old Mangrove, young and old Upper mountain, Tropical, Potiukan) honey of Sabah, Malaysian Borneo. Antioxidant activities were determined using FRAP (Ferric Reducing Antioxidant Power), DPPH free radical scavenging and ABTS decolourization assays. Acetylcholinesterase inhibition effect was determined by enzyme inhibition method. The results of this study showed that wild honey produced by A.cerana collected from the Acacia tree extracted using 80% methanol displayed the highest DPPH free radical scavenging activity and ABTS decolorization assays. Whereas wild honey produced by A.nuluensis collected from the Chestnut tree extracted using 80% methanol displayed the highest FRAP activity. The wild honey produced by A. nuluensis also displayed the highest acetylcholinesterase properties as the antioxidant compounds contributed to the inhibitory properties of the enzyme. Manuka honey (produced from tea tree) found to be higher in antioxidant and acetylcholinesterase properties as compared to all other samples. The same trend of bioactivity was also observed in absolute methanol extracts. Strong positive correlation was found between antioxidant and acetylcholinesterase activity. Therefore, honey has the potential as natural antioxidant and acetylcholinesterase inhibition sources with promising potential benefits to human’s health.

Matched MeSH terms: Free Radicals
Fulltext Antioxidant activity of red algae Kappaphycus alvarezii and Kappaphycus striatum

Farah Diyana, A., Abdullah, A., Shahrul Hisham, Z.A., Chan, K. M.

International Food Research Journal, 2015;22(5):1977-1984.
MyJurnal

Antioxidants in seaweeds have attracted increasing interest for its role in protecting human health. Therefore, the aim of this study was to assess the Total phenolic content (TPC) values and antioxidant activities in red seaweeds Kappaphycus alvarezii and Kappaphycus striatum of different solvent extracts. Total phenolic content (TPC) and antioxidant activities (DPPH scavenging assay and Trolox equivalent antioxidant capacity assay, TEAC) for both K. alvarezii and K. striatum extracts were determined using different solvents at different concentrations (ethanol: 50%, 70%, 100%; acetone: 50%, 70%, 100%; methanol: 50%, 70%, 100%). The TPC value was measured using the Folin-Ciocalteu’s method. The antioxidant activities were measured by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and Trolox Equivalent Antioxidant Capacity (TEAC) assay. The highest TPC value of K. alvarezii antioxidant extract was obtained by 50% ethanol extracts while for K. striatum obtained by 50% methanol extract. The highest percentage of DPPH free radical inhibition for K. alvarezii was shown by 50% acetone extract while K. striatum was shown using 50% methanol extract. The highest TEAC value for K. alvarezii was shown by 50% acetone while K. striatum extract was shown by 50% ethanol extract. The TPC values and antioxidant activities of all solvent extracts of K. striatum were significantly higher (p< 0.05) than K. alvarezii antioxidant extracts. The TPC values showed strong correlation (r = 0.797) with TEAC values for K. alvarezii antioxidant extract (p< 0.01). The TEAC values also showed strong correlation (r = 0.735) with percentage of DPPH free radical inhibition for K. alvarezii (p< 0.01). The TPC value, DPPH free radical scavenging assay and TEAC assay for K. striatum extracts showed strong correlation (r> 0.8) with each other (p< 0.01). In summary, K. striatum showed better antioxidant activity and higher TPC value than K. alvarezii.

Matched MeSH terms: Free Radicals
Fulltext Effect of different drying methods on phytochemicals and antioxidant properties of unfermented and fermented teas from Sabah Snake Grass (Clinacanthus nutans Lind.) leaves

Lusia Barek, M., Hasmadi, M., Zaleha, A.Z., Mohd Fadzelly, A.B.

International Food Research Journal, 2015;22(2):661-670.
MyJurnal

Clinacanthus nutans (Burm. F.) Lindau or locally known in Sabah, Malaysia as ‘Sabah Snake Grass’ has been ethnobotanically used to treat various diseases in Asian countries. This study was conducted to determine the total phenolics content (TPC), flavonoids content (TFC) and antioxidant activity of herbal teas developed from C. nutans leaves with different drying techniques (microwave-oven dried and freeze dried) and infusion time (1, 2, 5, 10, 15 and 20 min). Ferric reducing/antioxidant power (FRAP) assay, 2,2’-azino-bis(3-ethylbenzothiazoline- 6-sulphonic acid (ABTS) and 2, 2-diphenyl-1-pycryl-hydrazyl (DPPH) free radical scavenging assays were used to investigate the antioxidant capacity. The highest TPC of herbal tea was observed in 20 min infusion of unfermented microwave-oven dried leaves (177.80 ± 19.10 mg TAE/L), while the highest TFC was observed in 10 min infusion of fermented microwave-oven dried leaves (22.13 ± 1.53 mg CE/L). Short infusion times from 5 min to 15 min were able to extract high amount of phenolics compounds. Unfermented tea contained higher TPC content (P < 0.05) as compared to fermented tea, while, TFC showed no significant difference between both types. Freeze dried infusion shows no significant difference (P > 0.05) as compared to microwave-oven dried for TPC, TFC and antioxidant capacity. Moderate and low correlation was observed between TPC and FRAP values (r = 0.507) and between TFC and ABTS values (r = 0.256). Preparation of C. nutans herbal tea as potential natural antioxidant source can be used as a basic reference for future research on the dietary intake of these herbal teas.

Matched MeSH terms: Free Radicals
Fulltext Quantification of gallic acid and tannic acid from quercus infectoria (manjakani) and their effects on antioxidant and antibacterial activities

Ab. Rahman, N.S., Abd. Majid F.A., Harisun, Y., Md. Salleh L.

Pertanika Journal of Science & Technology, 2015;23(2):351-362.
MyJurnal

Effects of different types of solvent on the antioxidant and antibacterial activity of Quercus infectoria extract have not been well documented. Therefore, extraction process was conducted using conventional Soxhlet extraction with six different types of solvent (100% methanol, ethanol, acetone, water and 70% methanol, and ethanol). High performance liquid chromatography was implemented to identify gallic acid and tannic acid in the extracts. Water extracts contained the highest concentration of both gallic acid and tannic acid compared to other types of solvent; 51.14 mg/g sample and 1332.88 mg/g sample of gallic acid and tannic acid. Meanwhile, antioxidant and antibacterial activity were tested using DPPH free radicals scavenging and disc diffusion assay. Results demonstrated that water extracts gave the highest antioxidant activity (approximately 94.55%), while acetone extract gave the largest inhibition zone for disc diffusion assay (19.00mm respectively). The results also revealed rich sources of gallic acid and tannic acid in Q. infectoria which might provide a novel source of these natural antioxidant and antibacterial activity.

Matched MeSH terms: Free Radicals

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