Displaying publications 41 - 60 of 176 in total

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  1. Assessment of antioxidant activity in Victorian marine algal extracts using high performance thin-layer chromatography and multivariate analysis
    Agatonovic-Kustrin S, Morton DW, Ristivojević P
    J Chromatogr A, 2016 Oct 14;1468:228-235.
    PMID: 27670751 DOI: 10.1016/j.chroma.2016.09.041
    The aim of this study was to develop and validate a rapid and simple high performance thin layer chromatographic (HPTLC) method to screen for antioxidant activity in algal samples. 16 algal species were collected from local Victorian beaches. Fucoxanthin, one of the most abundant marine carotenoids was quantified directly from the HPTLC plates before derivatization, while derivatization either with 2,2-diphenyl-1-picrylhydrazyl (DPPH) or ferric chloride (FeCl3) was used to analyze antioxidants in marine algae, based on their ability to scavenge non biological stable free radical (DPPH) or to chelate iron ions. Principal component analysis of obtained HPTLC fingerprints has classified algae species into 5 groups according to their chemical/antioxidant profiles. The investigated brown algae samples were found to be rich in non-and moderate-polar compounds and phenolic compounds with antioxidant activity. Most of the phenolic iron chelators also have shown free radical scavenging activity. Strong positive and significant correlations between total phenolic content and DPPH radical scavenging activity showed that, phenolic compounds, including flavonoids are the main contributors of antioxidant activity in these species. The results suggest that certain brown algae possess significantly higher antioxidant potential when compared to red or green algae and could be considered for future applications in medicine, dietary supplements, cosmetics or food industries. Cystophora monilifera extract was found to have the highest antioxidant concentration, followed by Zonaria angustata, Cystophora pectinate, Codium fragile, and Cystophora pectinata. Fucoxanthin was found mainly in the brown algae species. The proposed methods provide an edge in terms of screening for antioxidants and quantification of antioxidant constituents in complex mixtures. The current application also demonstrates flexibility and versatility of a standard HPTLC system in the drug discovery. Proposed methods could be used for the bioassay-guided isolation of unknown natural antioxidants and subsequent identification if combined with spectroscopic identification.
    Matched MeSH terms: Picrates/chemistry
  2. Fulltext Synthesis, crystal structure, DFT studies and evaluation of the antioxidant activity of 3,4-dimethoxybenzenamine schiff bases
    Aziz AN, Taha M, Ismail NH, Anouar el H, Yousuf S, Jamil W, et al.
    Molecules, 2014 Jun 19;19(6):8414-33.
    PMID: 24950444 DOI: 10.3390/molecules19068414
    Schiff bases of 3,4-dimethoxybenzenamine 1-25 were synthesized and evaluated for their antioxidant activity. All the synthesized compounds were characterized by various spectroscopic techniques. In addition, the characterizations of compounds 13, 15 and 16 were supported by crystal X-ray determinations and their geometrical parameters were compared with theoretical DFT calculations at the B3LYP level of theory. Furthermore, the X-ray crystal data of two non-crystalline compounds 8 and 18 were theoretically calculated and compared with the practical values of compounds 13, 15, 16 and found a good agreement. The compounds showed good DPPH scavenging activity ranging from 10.12 to 84.34 μM where compounds 1-4 and 6 showed stronger activity than the standard n-propyl gallate. For the superoxide anion radical assay, compounds 1-3 showed better activity than the standard.
    Matched MeSH terms: Picrates/chemistry
  3. Fulltext Phenolic content, antioxidant effect and cytotoxic activity of Leea indica leaves
    Reddy NS, Navanesan S, Sinniah SK, Wahab NA, Sim KS
    BMC Complement Altern Med, 2012 Aug 17;12:128.
    PMID: 22898370 DOI: 10.1186/1472-6882-12-128
    BACKGROUND: The leaves of Leea indica (Vitaceae), commonly known as 'Huo Tong Shu' in Malaysia, have been traditionally used as natural remedy in folk medicine by the locals. The current study reports the outcome of antioxidant and cytotoxic investigation of L. indica leaves. To the best of our knowledge, this is the first report of L. indica leaf crude ethanol and its fractionated extracts (hexane, ethyl acetate and water) for evaluation of total phenolic content, antioxidant effect and cytotoxic activity against colon cancer cell lines.

    METHODS: In the present study, L. indica leaf crude ethanol and its fractionated extracts (hexane, ethyl acetate and water) were firstly prepared prior to phenolic content, antioxidant effect and cytotoxic activity assessment. Folin-Ciocalteau's method was used for the measurement of total phenolic content of the extracts. The antioxidant activity was measured by employing three different established testing systems, such as scavenging activity on DPPH (1,1-diphenyl-2-picrylhydrazyl) radicals, reducing power assay and SOD (superoxide dismutase) activity assay. The cytotoxic activity of the extracts were evaluated against three colon cancer cell lines with varying molecular characteristics (HT-29, HCT-15 and HCT-116) by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay.

    RESULTS: The total phenolic content and antioxidant capabilities differed significantly among the L. indica leaf extracts. A strong correlation between total phenolic content and antioxidant properties was found, indicating that phenolic compounds are the major contributor to the antioxidant properties of these extracts. Among the crude ethanol and its fractionated extracts, fractionated water extract showed significantly the highest total phenolic content and strongest antioxidant effect in all the antioxidant testing systems employed in this study. All the four extracts exert no damage to the selected colon cancer cells.

    CONCLUSIONS: The data obtained in these testing systems clearly establish the antioxidant potency of the fractionated water extract of L. indica leaves. Additional studies should be carried out to isolate and identify the bioactive compounds in the fractionated water extract, in order to provide more convincing evidence.

    Matched MeSH terms: Picrates/metabolism
  4. Fulltext Antioxidant Activity and Total Phenolic and Flavonoid Content of Various Solvent Extracts from In Vivo and In Vitro Grown Trifolium pratense L. (Red Clover)
    Khorasani Esmaeili A, Mat Taha R, Mohajer S, Banisalam B
    Biomed Res Int, 2015;2015:643285.
    PMID: 26064936 DOI: 10.1155/2015/643285
    In the present study the extracts of in vivo and in vitro grown plants as well as callus tissue of red clover were tested for their antioxidant activities, using different extraction solvent and different antioxidant assays. The total flavonoid and phenolic contents as well as extraction yield of the extracts were also investigated to determine their correlation with the antioxidant activity of the extracts. Among all the tested extracts the highest amounts of total phenolic and total flavonoids content were found in methanol extract of in vivo grown plants. The antioxidant activity of tested samples followed the order in vivo plant extract > callus extract > in vitro extract. The highest reducing power, 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging, and chelating power were found in methanol extracts of in vivo grown red clover, while the chloroform fraction of in vivo grown plants showed the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, superoxide anion radical scavenging and hydrogen peroxide scavenging compared to the other tested extracts. A significant correlation was found between the antioxidant activity of extracts and their total phenolic and total flavonoid content. According to the findings, the extract of in vitro culture of red clover especially the callus tissue possesses a comparable antioxidant activity to the in vivo cultured plants' extract.
    Matched MeSH terms: Picrates/pharmacology; Picrates/chemistry
  5. Fulltext (+)-Kunstlerone, a new antioxidant neolignan from the Leaves of Beilschmiedia kunstleri gamble
    Mollataghi A, Hadi AH, Awang K, Mohamad J, Litaudon M, Mukhtar MR
    Molecules, 2011 Aug 04;16(8):6582-90.
    PMID: 21818061 DOI: 10.3390/molecules16086582
    A new neolignan, 3,4-dimethoxy-3',4'-methylenedioxy-2,9-epoxy-6,7-cyclo-1,8-neolign-11-en-5(5H)-one, which has been named (+)-kunstlerone (1), together with six known alkaloids: (+)-norboldine (2), (+)-N-methylisococlaurine (3), (+)-cassythicine (4), (+)-laurotetanine (5), (+)-boldine (6) and (-)-pallidine (7), were isolated from the leaves of Beilschmiedia kunstleri. The structures were established through various spectroscopic methods notably 1D- and 2D-NMR, UV, IR and LCMS-IT-TOF. (+)- Kunstlerone (1) showed a strong antioxidant activity, with an SC(50) of 20.0 µg/mL.
    Matched MeSH terms: Picrates/antagonists & inhibitors; Picrates/metabolism
  6. Fulltext HPLC and GC-MS determination of bioactive compounds in microwave obtained extracts of three varieties of Labisia pumila Benth
    Karimi E, Jaafar HZ
    Molecules, 2011 Aug 09;16(8):6791-805.
    PMID: 21829154 DOI: 10.3390/molecules16086791
    Microwave extraction of phytochemicals from medicinal plant materials has generated tremendous research interest and shown great potential. This research highlights the importance of microwave extraction in the analysis of flavonoids, isoflavonoid and phenolics and the antioxidant properties of extracts from three varieties of the Malaysian medicinal herb, Labisia pumila Benth. High and fast extraction performance ability, equal or higher extraction efficiencies than other methods, and the need for small samples and reagent volumes are some of the attractive features of this new promising microwave assisted extraction (MAE) technique. The aims of the present research were to determine the foliar phenolics and flavonoids contents of extracts of three varieties of L. pumila obtained by a microwave extraction method while flavonoid, isoflavonoid and phenolic compounds were analyzed using RP-HPLC. Furthermore, the antioxidant activities were measured by the DPPH and FRAP methods and finally, the chemical composition of the crude methanolic extracts of the leaves of all three varieties were analyzed by GS-MS.
    Matched MeSH terms: Picrates/antagonists & inhibitors; Picrates/metabolism
  7. Fulltext The antioxidant activity of new coumarin derivatives
    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: Picrates/antagonists & inhibitors; Picrates/metabolism; Picrates/chemistry
  8. Chloroquine polymeric membrane electrodes: Development and applications
    Saad B, Kanapathy K, Ahmad MN, Hussin AH, Ismail Z
    Talanta, 1991 Dec;38(12):1399-402.
    PMID: 18965315
    Three main types of PVC solvent polymeric membrane ion-selective electrodes for chloroquine are described. They are based on three ion-pairing agents namely dipicrylamine (DPA), tetraphenylborate (TPB) or tetrakis(4-chlorophenyl)borate (TCPB) with either dioctylphenyl phosphonate (DOPP) or trioctyl phosphate (TOP) solvent mediator. All electrodes exhibit Nernstian responses, fast dynamic response times and a wide useful pH range. The best all-round electrode is based on TPB and TOP plasticizing solvent mediators with a limit of detection of 7.1 x 10(-6)M and was utilized for the assay of chloroquine in tablets. Direct potentiometric determinations with either the analyte addition method or the normal calibration method gave results comparable to the official method.
    Matched MeSH terms: Picrates
  9. Fulltext Multifunctional Tyrosinase Inhibitor Peptides with Copper Chelating, UV-Absorption and Antioxidant Activities: Kinetic and Docking Studies
    Yap PG, Gan CY
    Foods, 2021 Mar 22;10(3).
    PMID: 33810046 DOI: 10.3390/foods10030675
    Nature-derived tyrosinase inhibitors are of great industrial interest. Three monophenolase inhibitor peptides (MIPs) and three diphenolase inhibitor peptides (DIPs) from a previous study were investigated for their in vitro tyrosinase inhibitory effects, mode of inhibition, copper-chelating activity, sun protection factor (SPF) and antioxidant activities. DIP1 was found to be the most potent tyrosinase inhibitor (IC50 = 3.04 ± 0.39 mM), which could be due to the binding interactions between its aromatic amino acid residues (Y2 and D7) with tyrosinase hotspots (H85, V248, H258, H263, F264, R268, V283 and E322) and its ability to chelate copper ion within the substrate-binding pocket. The conjugated planar rings of tyrosine and tryptophan may interact with histidine within the active site to provide stability upon enzyme-peptide binding. This postulation was later confirmed as the Lineweaver-Burk analysis had identified DIP1 as a competitive inhibitor and DIP1 also showed 36.27 ± 1.17% of copper chelating activity. In addition, DIP1 provided the highest SPF value (11.9 ± 0.04) as well as ferric reducing antioxidant power (FRAP) (5.09 ± 0.13 mM FeSO4), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) (11.34 ± 0.90%) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) (29.14 ± 1.36%) free radical scavenging activities compared to other peptides. These results demonstrated that DIP1 could be a multifunctional anti-tyrosinase agent with pharmaceutical and cosmeceutical applications.
    Matched MeSH terms: Picrates
  10. Fulltext Optimized aqueous extraction conditions for maximal phenolics, flavonoids and antioxidant capacity from Artocarpus heterophyllus (Jackfruit) leaves by response surface methodology (RSM)
    Nor Hafiza Sayuti, ‘Ammar Akram Kamarudin, Nor Asma Ab. Razak, Norazalina Saad, Mohd Sabri Pak Dek, Norhaizan Mohd Esa
    Malaysian Journal of Medicine and Health Sciences, 2020;16(2):135-144.
    MyJurnal
    Introduction: There are numerous studies on the therapeutic properties of Artocarpus heterophyllus. However, stud- ies on the aqueous extraction of A. heterophyllus leaves are limited. This present study was conducted to optimize the extraction conditions of A. heterophyllus leaves to yield the highest phenolic, flavonoids and antioxidant contents. Methods: Response surface methodology (RSM) was employed to obtain a higher phenolic extraction parameter(s) of A. heterophyllus leaves using Central Composite Design (CCD). The antioxidant activity was then determined via ABTS (2,29-azinobis (3 ethylbenzothiazoline-6-sulfonic acid)) and DPPH (2,2-Diphenyl-1-picrylhydrazyl) assay and analysis of the individual phenolics was performed by high performance liquid chromatography (HPLC). Results: The optimum extraction conditions with higher phenolics content and antioxidant activity was achieved at 81°C, 100 min and 40 mL/g sample with a good desirability value of 0.87. Under these optimized parameters, total phenolics and flavonoids were 174.48 ± 4.05 mg GAE/g sample and 21.44 ± 0.05 mg RE/g sample, respectively. Meanwhile, antioxidant activity via ABTS and DPPH assays were 90.88% ± 0.09 and 87.22% ± 0.62, respectively. Finally, under optimal extraction conditions revealed 4 compounds identified as chlorogenic acid, quercetin, rutin and kaempferol. Conclusion: The optimisation are promising to improve phenolic yield and antioxidant activity in A. heterophyllus leaves. It also proved that A. heterophyllus leaves can be used as an alternative natural antioxidant especially in medicinal applications since all identified compound possess significant biological activities for human health.
    Matched MeSH terms: Picrates
  11. Fulltext Impact of juice extraction method on the physicochemical, functional, and sensory properties of Sabah snake grass (Clinacanthus nutans) juice mix
    Noranizan, M., Pean, L. F., Li, J. W., Aadil, R. M., Ahmad, T., Rosli, S. Z., et al.
    International Food Research Journal, 2020;27(5):835-845.
    MyJurnal
    The present work investigated the impact of several juice extraction methods (blender,
    centrifugal juicer, and slow juicer) and thermal pasteurisation (72°C, 15 s) on the different
    properties [physicochemical, polyphenol oxidase (PPO) activity, and functional] of
    Clinacanthus nutans juice mix during storage (28 d, 4°C). Regardless of juicing technique, all
    juices had similar colour and antioxidants [tested using 2,2-diphenyl-1-picrylhydrazyl
    (DPPH) and ferric reducing antioxidant power (FRAP) methods]. The juices also had similar
    PPO activity and sensory acceptance in terms of colour, aroma, flavour, mouthfeel, and
    overall acceptability. The blender yielded juice with higher pH, soluble solids, and relative
    viscosity than other methods. The slow juicer was the best at retaining ascorbic acid (39.33 ±
    3.06 mg/100 mL), while the blender was best at retaining phenolic compounds (11.82 ± 0.12
    mg gallic acid equivalents/100 mL) and chlorophyll (6.95 ± 0.31 μg/mL). Pasteurisation
    negatively affected the colour, functional properties, and sensory characteristics (colour,
    aroma, flavour, and mouthfeel) of the juice.
    Matched MeSH terms: Picrates
  12. Fulltext CORRELATION BETWEEN TPC AND TFC WITH ANTIOXIDANT ACTIVITY OF Piper sarmentosum EXTRACT AND ITS FORMULATION FOR COSMETIC PURPOSES
    WAN ASIAH WAN SUKAIRI, LAILI CHE ROSE, ASNUZILAWATI ASARI, RAZIFAH MOHD RAZALI
    UMT Journal of Undergraduate Research, 2021;3(2):51-60.
    MyJurnal
    This study investigates the characteristics of an antioxidant cream made from the methanol extract of Piper sarmentosum leaves, which is locally known as the wild betel or pokok kadok in Malay. The secondary metabolites of the leaves were subjected to phytochemical tests to detect the presence of natural compounds. Antioxidant activity was described by its total phenolic content (TPC) and total flavonoid content (TFC), which was assessed by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay. A phase diagram was constructed to find a possible region to formulate an antioxidant cream. In phytochemical screening, the methanolic extract showed positive presence of alkaloids, flavonoids, steroids, terpenoids and tannins. In quantitative analysis of antioxidative components, besides having significantly higher TFC content compared with quercetin (P
    Matched MeSH terms: Picrates
  13. Fulltext STUDY OF MORPHOLOGY, PREVALENCE AND MEAN INTENSITY OF MONOGENEANS INFECTING POND REARED Pangasianodon hypophthalmus(STRIPED CATFISH) IN BESUT, TERENGGANU
    SARAH SALEHAH
    UMT Journal of Undergraduate Research, 2019;1(1):33-40.
    MyJurnal
    This study was conducted to determine the morphology, prevalence and mean intensity of monogeneans on gill filaments of striped catfish Pangasianodon hypophthalmus (Pangasiidae).P. hypophthalmus are important economic fish in Southeast Asia region and predominantly produced in Asian countries such as Malaysia, Bangladesh, Indonesia, Vietnam, Laos, China and Cambodia through aquaculture. Thirty fish were sampled from an earthen pond located in Kuala Besut, Terengganu, in the period from January to February, 2018. The monogenean parasites were removed from the gill filaments and counted. For the morphological study, the extracted monogeneanswere mounted on a slide by using drop of ammonium picrate-glycerin (APG) and then were observed under the Compound Advanced Research Microscope. The drawing was done with the aid of lucida camera attached to compound microscope. The monogenean parasite was identified as Thaparocleidussp based on the characteristics of the morphology and morphometrics of the parasite, which did not differ significantly from the previous descriptions of the same species discovered in other geographic locations. The prevalence and mean intensity levels were 100% and 106.07 parasites per fish, respectively. The monogenean parasites discovered throughout this examination were recorded and the data obtained was summarized.
    Matched MeSH terms: Picrates
  14. Fulltext Effect of Cosmos caudatus kunth. (ulam raja) aqueous and dry extracts on the physicochemical and functional properties, and sensory acceptability of herbal yellow alkaline noodles
    Norlaili, A.H., Roselina, K., Muhammad, T.S.
    Malays J Nutr, 2014;20(3):403-415.
    MyJurnal
    Introduction: Cosmos caudatus (Ulam Raja) is rich in phytochemicals and can be utilised in diet diversification strategies to improve the health of individuals. lbis study was designed to incorporate dry and aqueous extracts of C. caudatus for the preparation of herbal noodles. Methods: For this purpose, different proportions of dry extract (2, 4 and 6% dry extract) and aqueous extract (5, 10 and 15% aqueous extract) of C. caudatus were used. The physicochemical properties of noodles evaluated were pH, cooking time, cooking loss, texture and colour. Total polyphenol contents (TPq and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay were carried out to assess the antioxidant potential. Lastly, sensory appraisal of functional noodles was carried out to assess consumer acceptance and marketability. Results: The results on physicochemical properties indicated that the pH value of noodles varied from 8.66 to 10.47. In terms of textural analysis and colour properties, firmness and greenness (a*) were higher in dry extract noodles. TPC varied between 115to149 mg gallic acid equivalents (GAE/lOOg) whilst the highest DPPH free radical inhibition was exhibited in herbal noodles prepared using 4% dry extract (92.8%). In contrast, in terms of sensory appraisal, herbal noodles prepared with aqueous extract were more acceptable than dry extract noodles. Conclusion: C. caudatus can be utilised to prepare herbal noodles thus enhancing the dietary intake of phytochemicals especially antioxidants. Such functional foods can improve the health of consumers and offer the potential of protection against various ailments.
    Matched MeSH terms: Picrates
  15. Fulltext An exotic fruit with high nutritional value: Kadsura coccinea fruit
    Sun, J., Jiang, Y., Amin, I., Li, Z., Prasad, K.N., Duan, X., et al.
    International Food Research Journal, 2011;18(2):651-657.
    MyJurnal
    This research was to determine nutritional composition, essential and toxic elemental content, and major phenolic acid with antioxidant activity in Kadsura coccinea fruit. The results indicated that Kadsura coccinea fruit exhibited the high contents of total protein, total fat, ash and essential elements such as calcium (Ca), ferrum (Fe) and phosphorus (P). The levels of four common toxic elements, i.e. cadmium (Cd), mercury (Hg), arsenic (As) and lead (Pb), were lower than legal limits. By high-performance liquid chromatography (HPLC) analysis, gallic acid was identified as major phenolic acid in peel and pulp tissues. Its contents were no significant difference in both tissues. In comparison with two commercial antioxidants, the major phenolic acid extracted from Kadsura coccinea exhibited stronger 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activity and reducing power. Kadsura coccinea fruit is a good source of nutrition and natural antioxidant. It is worthwhile to popularize this exotic fruit around the world.
    Matched MeSH terms: Picrates
  16. Fulltext Quantification of total phenolic compound and in vitro antioxidant potential of fruit peel extracts
    Marina, Z., Noriham, A.
    International Food Research Journal, 2014;21(5):1925-1929.
    MyJurnal
    This study was undertaken to evaluate the potential of fruit waste materials as source of natural antioxidant. The fruit peels including mango, guava and papaya peel were used in this study. The total phenolic content (TPC) was determined by Folin-Ciocalteu assay while antioxidant activities were determined by using ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, ferric thiocynate (FTC) and thiobarbituric acid (TBA) assays. These antioxidant activities were compared to synthetic antioxidants, BHA/BHT combination and ascorbic acid. The results demonstrated that TPC ranged from 3.23 to 15.84 g GAE/100 g extract. Mango peels extract exhibited highest TPC compared to guava peel and papaya peel extract. In the FRAP assay, mango peel extract at 200 ppm, guava peel extract at 400 ppm and papaya peel extract at 1200 ppm, exhibited reducing power comparable to the permissible amount of BHA/BHT at 200 ppm. At concentration of 250 μg/ml, the DPPH radical scavenging activity of extracts and standards decreased significantly in the order of mango peel extract > guava peel extract > BHA/BHT > ascorbic acid > papaya peel extract. For the FTC assay, the antioxidant activity of mango peel extract was significantly higher than ascorbic acid, guava peel and papaya peel extract but lower than BHA/BHT while in the TBA assay, percentage inhibition of BHA/BHT and ascorbic acid were found to be higher than fruit peel extracts. The quantitative analysis for flavonoids showed the presence of catechin, epicatechin and kaempferol in the peel extracts.
    Matched MeSH terms: Picrates
  17. Fulltext Differences in chemical components and antioxidant-related substances in virgin coconut oil from coconut hybrids and their parents
    Arlee, R., Suanphairoch, S., Pakdeechanuan, P.
    International Food Research Journal, 2013;20(5):0-0.
    MyJurnal
    Chumphon Horticultural Research Centre (CHRC) is Thailand’s main coconut research unit. CHRC has developed three coconut cultivars: Sawi Hybrid No. 1 (Malayan Yellow Dwarf x West African Tall: MYD x WAT), Chumphon Hybrid No. 60 (Thai Tall: THT x WAT) and Chumphon Hybrid No. 2 (MYD x THT). This study compared some chemical components in virgin coconut oil (VCO) from coconut hybrids with their parents. The VCO was extracted by cold pressing and fermentation methods, and was analyzed for fatty acid profiles, triacylglycerol profile, acid value, tocopherol content, total phenolic content, and antioxidant activity against DPPH (1,1-diphenyl-2-picrylhydrazyl) radicals. The findings showed that hybrids contained lauric acid ranging from 46.63 to 48.34% of total fatty acid. Chumphon 60 had the highest lauric acid content, 48.34% of total fatty acids, which was not significantly different (p > 0.05) from that of the parents. In contrast, the cultivars from MYD, Sawi 1 and Chumphon 2, had significantly greater lauric acid content than the parent MYD (p ≤ 0.05). Cold pressing and fermentation provided an oil extraction yield of 25 and 20%, respectively. The proportions of lauric acid in VCO from these two methods were not significantly different (p > 0.05), but the cold pressing method resulted in higher tocopherol content (p ≤ 0.05). The VCO of Chumphon 60 from the cold pressed method had tocopherol content close to that of the parent WAT (p > 0.05) but significantly higher than that of the other parent THT (p ≤ 0.05). In addition, it contained the highest total phenolic contents among the three cultivars, 57.89 mg GAE/100 g oil, leading to antioxidant activity with a low EC50 of 0.53 mg GAE/ml. Overall, the hybrid of WAT x THT, Chumphon 60, was outstanding among the cultivars; it had the highest levels of lauric acid, total phenolic compounds, and antioxidant activity.
    Matched MeSH terms: Picrates
  18. Fulltext Anti-hypertensive effect of pink guava (Psidium guajava) puree on spontaneous hypertensive rats
    Ayub, M.Y., Norazmir, M.N., Mamot, S., Jeeven, K., Hadijah, H.
    International Food Research Journal, 2010;17(1):89-96.
    MyJurnal
    The objective of this study was to determine the physicochemical properties of pink guava (Psidium guajava) puree and its anti-hypertensive effect on Spontaneous Hypertensive Rats (SHR). Antioxidant activities of pink guava puree in water and ethanol extracts, based on 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, were 1.43±0.04 mg/gfm and 0.28±0.01 mg/gfm, respectively. A total of 24 male SHRs were divided into a control group, CG, and 3 treatment dosage groups [low dose group, LDG (0.5 g/kg body weight/day), medium dose group, MDG (1.0 g/kg body weight/day), and high dose group, HDG (2.0 g/kg body weight/day)]. Final body weights for treatment dosage groups were lower [MDG (313.01±31.25 g), HDG (318.56±17.96 g), LDG (320.01±22.70 g)] compared to CG (331.08±41.29 g). Final systolic blood pressure values from the beginning and the end of the experiment in MDG and HDG were 231-179 mmHg and 246-169mm Hg, respectively. These results were significantly lower when compared with CG (241-223 mmHg) from the beginning until the end of the experiment. As a conclusion, these results showed that pink guava puree has anti-hypertensive properties.
    Matched MeSH terms: Picrates
  19. Fulltext Optimal antioxidant activity with moderate concentrations of Tocotrienol rich fraction (TRF) in in vitro assays
    Muid, S., Ali, A.M., Yusoff, K., Nawawi, H.M.
    International Food Research Journal, 2013;20(2):687-694.
    MyJurnal
    Vitamin E is known to have potent antioxidant activity and plays an important role in reducing oxidative stress, a pivotal step in atherogenesis. However, several randomised clinical trials using α-tocopherol have failed to demonstrate consistent beneficial effects of antioxidants against atherosclerosis and clinical endpoints. Tocotrienol, a vitamin E compound analogue is shown to have more potent antioxidant activity compared to tocopherol. Finding the optimal anti-oxidative dose is crucial and may effectively be applied for cardioprotection in human. The objective of this study was to determine the optimal dose of tocotrienol rich fraction (TRF) with highest antioxidant activity in vitro using the ferric thiocyanate (FTC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and 2’, 7’- dichlorofluorescein diacetate (DCFHDA) assays. It was found that TRF exhibited potent antioxidant and free radical scavenging activities with an IC50 of 22.10 + 0.01 µg/ml. In all assays, TRF had optimal antioxidant activity at moderate concentrations (10-100 µg/ml). In conclusion, TRF has potent antioxidant activity, which is optimal at moderate concentrations.
    Matched MeSH terms: Picrates
  20. Fulltext Impact of Non-Thermal Processing on Antioxidant Activity, Phenolic content, Ascorbic Acid content and Color of Winter Melon Puree
    Wan Saidatul, S.W.K., Noriham, A., Zainal, S., Khairusy, S.Z., Nurain, A.
    International Food Research Journal, 2013;20(2):633-638.
    MyJurnal
    In the last decade, non-thermal processing for inactivating microorganisms has been developed in response to the worldwide interest for more fresh and improved quality of food products. Winter melon is a very perishable fruit, hence, processing into puree is a necessity. However application of heat in the production of puree could affect the nutritional values, thus, application of non thermal treatment in combination with preservation method is significant for this fruit. This study was conducted to evaluate the effect of non-thermal processing in combining with preservation method on antioxidant activity, level of key antioxidant groups (total phenolic and ascorbic acid content) and the color of winter melon puree. Total phenolic content (TPC) was measured using Folin-Ciocalteu reagent. Ascorbic acid (AA) was determined using 2,6-dichlorophenol-indophenol titration method. Antioxidant activity were determined using four antioxidant assays namely Ferric Reducing Antioxidant Potential (FRAP), Oxygen Radical Absorbance Capacity (ORAC), 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) and β-Carotene Bleaching Assays. For the TPC, puree with pH 3 (28.5±1.3 GAE/g fresh weight) exhibited high in TPC as compared to puree with pH 3.5 and unprocessed puree. In contrast, unprocessed puree contains significantly high ascorbic acid (AA) content (35.9 ± 1.8 mg/100 g fresh mass) as compared to pH 3.0 and pH 3.5 purees. In general, antioxidant activity for all assays of pH 3.0 and pH 3.5 purees were significantly higher (p
    Matched MeSH terms: Picrates
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