Displaying publications 21 - 40 of 62 in total

Abstract:
Sort:
  1. Fulltext Validation of SYBR green I based closed-tube loop-mediated isothermal amplification (LAMP) assay for diagnosis of knowlesi malaria
    Lai MY, Ooi CH, Lau YL
    Malar J, 2021 Mar 25;20(1):166.
    PMID: 33766038 DOI: 10.1186/s12936-021-03707-0
    BACKGROUND: As an alternative to PCR methods, LAMP is increasingly being used in the field of molecular diagnostics. Under isothermal conditions at 65 °C, the entire procedure takes approximately 30 min to complete. In this study, we establish a sensitive and visualized LAMP method in a closed-tube system for the detection of Plasmodium knowlesi.

    METHODS: A total of 71 malaria microscopy positive blood samples collected in blood spots were obtained from the Sarawak State Health Department. Using 18s rRNA as the target gene, nested PCR and SYBR green I LAMP assay were performed following the DNA extraction. The colour changes of LAMP end products were observed by naked eyes.

    RESULTS: LAMP assay demonstrated a detection limit of 10 copies/µL in comparison with 100 copies/µL nested PCR. Of 71 P. knowlesi blood samples collected, LAMP detected 69 microscopy-positive samples. LAMP exhibited higher sensitivity than nested PCR assay. The SYBR green I LAMP assay was 97.1% sensitive (95% CI 90.2-99.7%) and 100% specific (95% CI 83.2-100%). Without opening the cap, incorporation of SYBR green I into the inner cap of the tube enabled the direct visualization of results upon completion of amplification. The positives instantaneously turned green while the negatives remained orange.

    CONCLUSIONS: These results indicate that SYBR green I LAMP assay is a convenient diagnosis tool for the detection of P. knowlesi in remote settings.

    Matched MeSH terms: Benzothiazoles/chemistry*
  2. Assessment of in vitro antioxidant, antibacterial and immune activation potentials of aqueous and ethanol extracts of Phyllanthus niruri
    Amin ZA, Abdulla MA, Ali HM, Alshawsh MA, Qadir SW
    J Sci Food Agric, 2012 Jul;92(9):1874-7.
    PMID: 22231455 DOI: 10.1002/jsfa.5554
    Recently much attention has been paid to biologically active plants because of their low production cost and fewer adverse effects compared with chemical drugs. In the present investigation the bioactivity of Phyllanthus niruri ethanol and aqueous extracts was evaluated in vitro.
    Matched MeSH terms: Benzothiazoles
  3. Fulltext Optimization of extraction time and temperature on antioxidant activity of Schizophyllum commune aqueous extract using response surface methodology
    Yim HS, Chye FY, Rao V, Low JY, Matanjun P, How SE, et al.
    J Food Sci Technol, 2013 Apr;50(2):275-83.
    PMID: 24425917 DOI: 10.1007/s13197-011-0349-5
    Central composite design of response surface methodology (RSM) was employed to optimize the extraction time (X 1 : 99.5-290.5 min) and temperature (X 2 : 30.1-54.9 °C) of Schizophyllum commune aqueous extract with high antioxidant activities and total phenolic content (TPC). Results indicated that the data were adequately fitted into four second-order polynomial models. The extraction time and temperature were found to have significant linear, quadratic and interaction effects on antioxidant activities and TPC. The optimal extraction time and temperature were: 290.5 min and 35.7 °C (DPPH(•) scavenging ability); 180.7 min and 41.7 °C (ABTS(•+) inhibition ability); 185.2 min and 42.4 °C (ferric reducing antioxidant power, FRAP); 290.5 min and 40.3 °C (TPC). These optimum conditions yielded 85.10%; 94.31%; 0.74 mM Fe(2+) equivalent/100 g; 635.76 mg gallic acid equivalent/100 g, respectively. The yields of antioxidant activities and TPC obtained experimentally were close to its predicted values. The establishment of such model provides a good experimental basis employing RSM for optimizing the extraction time and temperature on antioxidants from S. commune aqueous extract.
    Matched MeSH terms: Benzothiazoles
  4. Fulltext The free radical scavenging and antioxidant activities of pod and seed extract of Clitoria fairchildiana (Howard)- an underutilized legume
    Annegowda HV, Bhat R, Tze LM, Karim AA, Mansor SM
    J Food Sci Technol, 2013 Jun;50(3):535-41.
    PMID: 24425949 DOI: 10.1007/s13197-011-0370-8
    We evaluated the phenolic content and antioxidant capacities of pod and seed extracts (in methanol, ethanol, and water) of an underutilized legume, Clitoria fairchildiana (Howard). The antioxidant capacity of the extracts was determined using the ferric reducing antioxidant potential assay, and the free radical-scavenging capacity was evaluated using 2,2-diphenyl-1-picrylhydrazyl radical-scavenging and ABTS assays. In addition, the total flavonoids, flavonols, and tannin contents were also determined. Overall, the methanol extracts of the pod contained high concentration of phenolics and showed high antioxidant capacities compared to seed extracts. In addition, a positive correlation was found between total phenol and tannin versus antioxidant capacity. Results of the present study indicate pods and seeds of C. fairchildiana to possess rich amount of natural antioxidants, and can be further explored for their possible use as a natural additive in food or in pharmaceutical industries.
    Matched MeSH terms: Benzothiazoles
  5. Optical Properties of Azo-Benzothiazole Side Chain Liquid Crystalline Polymers: Effect of Solvents, Substituents and Temperatures
    Dzulkharnien NSF, Karim MR, Zahid NI, Rahman NMMA, Abdullah I, Salleh NM
    J Fluoresc, 2019 Jul;29(4):1049-1056.
    PMID: 31338718 DOI: 10.1007/s10895-019-02418-9
    The optical properties of a series of side chain liquid crystalline polymers (P1-P3) containing azo-benzothiazole mesogen with different terminal substituents (-H, -CH3 and -OCH2CH3) in four organic solvents of varying polarity have been investigated by absorption and fluorescence spectral analysis. Solvatochromic studies of P1-P3 did not show any regular variation on the absorption and emission intensities with changing the polarity of solvent. Theoretical studies were performed based on different solvent correlation methods such as Dimroth-Reichardt and Kamlet-Taft methods to investigate the solute-solvent interactions. Both absorption and emission maxima of investigated polymers were bathochromically shifted with the replacement of sixth position hydrogen atom by electron donating groups in benzothiazole moiety. The emission intensities of the studied polymers showed decreasing trend with increasing temperature.
    Matched MeSH terms: Benzothiazoles
  6. Activity-guided fractionation and evaluation of potent antioxidants from extract of angel wings mushroom, Pleurotus porrigens (higher Basidiomycetes)
    Yim HS, Chye FY, Mah SY, Sia CM, Samuagam L, Ho CW
    Int J Med Mushrooms, 2013;15(1):9-19.
    PMID: 23510280
    Pleurotus porrigens is a well-known edible, wild mushroom enjoyed as a delicacy by aborigines in Sabah and as source of income for the aborigines who collect and sell them at tamu (local market). This study aimed to evaluate the antioxidant activity in vitro and identify potent antioxidative components of aqueous extracts of P. porrigens. The antioxidant activities were evaluated using DPPH radical scavenging ability, ABTS radical cation inhibition activity, ferric reducing/antioxidant power, and total phenolic content. Activity-guided purifications based on DPPH radical scavenging ability resulted in 5 subfractions (SF). The highest DPPH radical scavenging ability was found in SF-III and SF-IV, but all were lower than butylated hydroxyanisole (BHA) and α-tocopherol. Analysis with high-performance liquid chromatography-diode array detectors found presence of ascorbic acid and (+)-catechin in SFs of P. porrigens, as well as some unidentified components that may have contributed to the radical scavenging ability. In conclusion, aqueous extract of P. porrigens possesses promising antioxidant activities, although they are lesser in their partially purified SFs. Nonetheless, P. porrigens could be promoted as an antioxidant-rich food as part of a normal diet that provides antioxidative benefit.
    Matched MeSH terms: Benzothiazoles
  7. Determination of optimal extraction time and temperature by response surface methodology to obtain high-level antioxidant activity in culinary-medicinal oyster mushroom, Pleurotus ostreatus (Jacq.:Fr.) P. Kumm. (higher basidiomycetes)
    Lim SM, Yim HS
    Int J Med Mushrooms, 2012;14(6):593-602.
    PMID: 23510253
    A central composite design of response surface methodology (RSM) was employed to optimize the extraction time (X1: 266.4-393.6 min) and temperature (X2: 42.9-57.1°C) of Pleurotus ostreatus aqueous extract with high antioxidant activities, namely DPPH radical-scavenging activity, ABTS radical cation inhibition, and ferric reducing/antioxidant power, as well as total phenolic content (TPC). Results showed that the data were adequately fitted into four second-order polynomial models developed by RSM. The extraction time and temperature were found to have significant quadratic effects on antioxidant activities and TPC. The optimal extraction time and temperature were 282.3 min and 42.9°C (DPPH), 393.6 min and 42.9°C (ABTS), 340.4 min and 49.8°C (FRAP), and 347.6 min, 49.7°C (TPC), with corresponding yields of 53.32%, 73.20%, 37.14 mM Fe2+ equivalents/100 g, and 826.33 mg gallic acid equivalents/100 g, respectively. These experimental data were close to their predicted values. The establishment of such a model provides a good experimental basis for employing RSM to optimize the extraction time and temperature for high antioxidant activities from P. ostreatus.
    Matched MeSH terms: Benzothiazoles
  8. Standardized extract of Syzygium aqueum: a safe cosmetic ingredient
    Palanisamy UD, Ling LT, Manaharan T, Sivapalan V, Subramaniam T, Helme MH, et al.
    Int J Cosmet Sci, 2011 Jun;33(3):269-75.
    PMID: 21284663 DOI: 10.1111/j.1468-2494.2010.00637.x
    Syzygium aqueum, a species in the Myrtaceae family, commonly called the water jambu is native to Malaysia and Indonesia. It is well documented as a medicinal plant, and various parts of the tree have been used in traditional medicine, for instance as an antibiotic. In this study, we show S. aqueum leaf extracts to have a significant composition of phenolic compounds, protective activity against free radicals as well as low pro-oxidant capability. Its ethanolic extract, in particular, is characterized by its excellent radical scavenging activity of EC(50) of 133 μg mL(-1) 1,1-diphenyl-2-picryl-hydrazyl (DPPH), 65 μg mL(-1) 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) and 71 μg mL(-1) (Galvinoxyl), low pro-oxidant capabilities and a phenolic content of 585-670 mg GAE g(-1) extract. The extract also displayed other activities, deeming it an ideal cosmetic ingredient. A substantial tyrosinase inhibition activity with an IC(50) of about 60 μg mL(-1) was observed. In addition, the extract was also found to have anti-cellulite activity tested for its ability to cause 98% activation of lipolysis of adipocytes (fat cells) at a concentration of 25 μg mL(-1). In addition, the extract was not cytotoxic to Vero cell lines up to a concentration of 600 μg mL(-1). Although various parts of this plant have been used in traditional medicine, this is the first time it has been shown to have cosmeceutical properties. Therefore, the use of this extract, alone or in combination with other active principles, is of interest to the cosmetic industry.
    Matched MeSH terms: Benzothiazoles
  9. Mango leaf extract incorporated chitosan antioxidant film for active food packaging
    K R, G B, Banat F, Show PL, Cocoletzi HH
    Int J Biol Macromol, 2019 Apr 01;126:1234-1243.
    PMID: 30584938 DOI: 10.1016/j.ijbiomac.2018.12.196
    Health hazards associated with usage of plastic films for food preservation demands for development of active films from non-toxic and antioxidant rich bio-sources. The reported work highlights the development, characterization and application studies of chitosan films enhanced for their antioxidant activity by mango leaf extract (MLE) incorporation. Effect of MLE variation (1-5%) on the morphology, optical nature, water exposure and mechanical characteristics of the chitosan-MLE composite films was studied. Increase in the MLE concentration resulted in films with increased thickness and decreased moisture content. Contact angle, water solubility and vapor permeability analysis demonstrated the reduced hydrophilicity and water vapor penetrability of the films due to MLE inclusion. MLE films possessed better tensile strength (maximum of 23.06 ± 0.19 MPa) with reduced elongation ratio than the pure chitosan film (18.14 ± 0.72 MPa). Antioxidants assessment in terms of total phenolic content, DPPH radical scavenging, ferric reducing power and ABTS radical scavenging showed improved antioxidant activity with the incremental amounts of MLE in the chitosan films. Microscopic studies revealed the smooth, compact and dense nature of the MLE-chitosan films favouring low oxygen transport rates. Application studies to cashew nuts preservation for 28 days storage indicated 56% higher oxidation resistance for the 5% MLE film than a commercial polyamide/polyethylene film. Results highlight the potential and promising nature of MLE impregnated chitosan films as suitable alternative for active packaging films for food preservation.
    Matched MeSH terms: Benzothiazoles
  10. Optimization strategy for laccase immobilization on polyethylene terephthalate grafted with maleic anhydride electrospun nanofiber mat
    Mohd Syukri MS, A Rahman R, Mohamad Z, Md Illias R, Nik Mahmood NA, Jaafar NR
    Int J Biol Macromol, 2021 Jan 01;166:876-883.
    PMID: 33144251 DOI: 10.1016/j.ijbiomac.2020.10.244
    Enzyme immobilization has been known to be one of the methods to improve the stability and reusability of enzyme. In this study, a strategy to optimize laccase immobilization on polyethylene terephthalate grafted with maleic anhydride electrospun nanofiber mat (PET-g-MAH ENM) was developed. The development involves the screening and optimization processes of the crucial factors that influence the immobilization yield such as enzyme concentration, pH values, covalent bonding (CV) time, CV temperature, crosslinking (CL) time, CL temperature and glutaraldehyde concentration using two-level factorial design and Box-Behnken design (BBD), respectively. It was found that laccase concentration, pH values and glutaraldehyde concentration play important role in enhancing the immobilization yield of laccase on PET-g-MAH ENM in the screening process. Subsequently, the optimization result showed at 0.28 mg/ml laccase concentration, pH 3 and 0.45% (v/v) glutaraldehyde concentrations gave the highest immobilization yield at 87.64% which was 81.2% increment from the immobilization yield before optimization. Under the optimum condition, the immobilized laccase was able to oxidize 2, 2-azino-bis 3-ethylbenzothiazoline-6- sulfonic acid (ABTS) in a broad range of pH (pH 3-6) and temperature (20- 70 °C). Meanwhile, the kinetic parameters for Km and Vmax were 1.331 mM and 0.041 mM/min, respectively. It was concluded that the optimization of immobilized laccase on PET-g-MAH ENM enhance the performance of this biocatalyst.
    Matched MeSH terms: Benzothiazoles/chemistry
  11. Fulltext Effects of extraction conditions on antioxidant properties of sapodilla fruit (Manilkara zapota)
    Woo, P.F., Yim, H.S., Khoo, H.E., Sia, C.M., Ang, Y.K.
    International Food Research Journal, 2013;20(5):2065-2072.
    MyJurnal
    This study investigated the effects of different percentages of ethanol (0 - 100%), extraction times (1 - 5 h) and temperatures (25 - 60°C) on total phenolic content (TPC) and antioxidant activity (AA) of sapodilla pulp and peel. TPC was determined by Folin-Ciocalteu reagent method, while AA was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, 2,2-azino-bis-(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assay, ferric reducing antioxidant power (FRAP) assay and β-carotene bleaching (BCB) assay. Based on the optimal extraction conditions used, sapodilla pulp extract had TPC of 3.89 mg GAE/g, 63.20% of DPPH scavenging activity, 4.30% of ABTS scavenging activity, 19.17% of BCB activity, and FRAP value of 15.24 mg TE/g; while its peel extract had TPC of 9.23 mg GAE/g, 92.95% of DPPH scavenging activity, 5.36% of ABTS scavenging activity, 8.14% of BCB activity, and 27.85 mg TE/g (FRAP value). Using the optimal extraction conditions for sapodilla pulp (40% ethanol as extraction solvent that extracted at 60°C for 4 h) and sapodilla peel (80% ethanol and 2 h extraction time at 40°C), highest antioxidants can be extracted from the pulp and peel.
    Matched MeSH terms: Benzothiazoles
  12. Fulltext Effect of solid-to-solvent ratio on phenolic content and antioxidant capacities of “Dukung Anak” (Phyllanthus niruri)
    Wong, B.Y., Tan, C.P., Ho, C.W.
    International Food Research Journal, 2013;20(1):325-330.
    MyJurnal
    The objective of this study was to evaluate the effects of solid-to-solvent ratio (1:5. 1:10, 1:15 and 1:20) on the extraction of phenolic compounds (TPC and TFC) and antioxidant capacity (ABTS and DPPH radical scavenging capacity) of P. niruri. Solid-to-solvent ratio showed a significant effect for both phenolic compounds (TPC and TFC) and antioxidant capacity (ABTS and DPPH radical scavenging capacity) with 1:20 was the condition for extracting the highest of phenolic compounds (TPC and TFC) with a value of 5788.7 mg GAE/100 g DW and 1906.5 mg CE/100 g DW, respectively and exhibited high antioxidant capacities (ABTS and DPPH radical scavenging capacities) with a value of 0.820 mM and 1.598 mM, respectively among the four levels studied. TPC was positively and significantly correlated with ABTS and DPPH (r=0.999 and r=0.999) under the effects of solid-to-solvent ratio as compared to TFC, positively and strongly correlated (r=0.865 and r=0.868) with ABTS and DPPH.
    Matched MeSH terms: Benzothiazoles
  13. Fulltext Ultrasound-assisted extraction of valuable compounds from winter melon (Benincasa hispida) seeds
    Bimakr, M., Rahman, R.A., Saleena Taip, F., Adzahan, N.M., Islam Sarker, Z., Ganjloo, A
    International Food Research Journal, 2013;20(1):331-338.
    MyJurnal
    Ultrasound-assisted extraction (UAE) was applied for the extraction of bioactive valuable compounds from winter melon (Benincasa hispida) seeds. Effects of amplitude (25-75%), temperature (40-60°C) and sonication time (20-60 min) on crude extraction yield (CEY) and radical scavenging activities (RSA, % inhibition of DPPH˙ and ABTS˙+ free radicals) of extracts were determined using complete randomised design (CRD). The results showed that the CEY and RSA of extracts significantly affected by independent variables. The maximum value of CEY (97.14±0.36 mgg-1), scavenging of DPPH˙ radicals (32.12 ± 0.38%) and scavenging of ABTS˙+ radicals (40.52±0.73%) were obtained at the combined treatment conditions of 75%, 55°C and 40 min. The UAE results obtained were compared with those achieved by using conventional Soxhlet extraction (CSE) method. It was found UAE allowed extraction at lower temperature and the extracts obtained posses higher quality compare with CSE. UAE is a promising environment friendly technique for the extraction of bioactive compounds from winter melon (Benincasa hispida) seeds.
    Matched MeSH terms: Benzothiazoles
  14. 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: Benzothiazoles
  15. Fulltext Physicochemical quality, antioxidant compounds and activity of MD-2 pineapple fruit at five ripening stages
    Ding, P., Syazwani, S.
    International Food Research Journal, 2016;23(2):549-555.
    MyJurnal
    Although Malaysia is one of the important pineapple fruit producing and exporting country, the production of MD-2 pineapple fruit only started in 2009. Pineapple fruit has been harvested at different ripening stages for different markets. The information on Malaysian grown MD-2 pineapple fruit quality is lacking. Therefore this work was carried out with the aim to determine physicochemical quality, antioxidant compounds and activity of MD-2 pineapple fruit at five ripening stages. Ripening stage affected physicochemical quality of MD-2 pineapple fruit. Soluble solids concentration of MD-2 pineapple fruit increased from 15.41 to 18.02% SSC when fruit ripened from stage 1 to 4 and no significant difference was found in fruit between stage 4 and 5. The ascorbic acid content decreased while total carotenoids content increased as ripening stage advanced. The total phenolic content of both 80% methanol and water extraction solvents increased significantly as fruit ripened from stage 1 to 3 and reduced as fruit ripened to stage 5. The antioxidant activity of MD-2 pineapple fruit as assayed using DPPH, FRAP and ABTS showed similar trend as total phenolic content. These results suggest that ripening stage affect MD-2 pineapple fruit quality and nutritional values.
    Matched MeSH terms: Benzothiazoles
  16. Fulltext A binary solvent extraction system for phenolic antioxidants and its application to the estimation of antioxidant capacity in Andrographis paniculata extracts
    Thoo, Y.Y., Ng, S.Y., Khoo, M.Z., Wan Aida, W.M., Ho, C.W.
    International Food Research Journal, 2013;20(3):1103-1111.
    MyJurnal
    The effects of ethanol concentration (0-100%, v/v), extraction time (60-300 min) and extraction temperature (25-65°C) on the extraction of phenolic antioxidants from Andrographis paniculata was evaluated using single-factor experiments. The following complementary assays were used to screen the antioxidant properties of the crude extracts: total phenolic content (TPC), total flavonoid content (TFC), condensed tannin content (CTC), 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical-scavenging capacity and 2,2’-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity. The extraction conditions chosen had significant effects (p < 0.05) on the extraction of phenolic compounds and antioxidant capacity. The optimal conditions were 60% ethanol for 60 min at 65oC for phenolic compounds and at 25oC for antioxidant capacity. Strong negative significant (p < 0.05) correlations were observed between the phenolic compounds (TPC, TFC and CTC) and antioxidant capacity comprising ABTS (-0.924, -0.909, -0.887, respectively) and DPPH radical-scavenging capacities (-0.992, -0.938, -0.928, respectively) were determined under the influence of extraction temperature.
    Matched MeSH terms: Benzothiazoles
  17. Fulltext Antioxidant activity and physicochemical properties changes of papaya (Carica papaya L. cv. Hongkong) during different ripening stage
    Zuhair, R.A., Aminah, A., Sahilah, A.M., Eqbal, D.
    International Food Research Journal, 2013;20(4):1653-1659.
    MyJurnal
    Papaya (Carica papaya L. cv. Hongkong) is an economically important fruit crop grown in Malaysia. During its ripening stages, (C. papaya L.) exhibits different physicochemical properties, antioxidant capacities, and sensory quality results. The objective of this study was to elucidate in detail the antioxidant capacity of C. papaya as determined by total phenol content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP),2,2-diphenyl-1-picrylhydrazyl (DPPH) and scavenging systemand (ABTS). The study also aimed to study physicochemical changes of papaya fruits based on measured pH, titratable acidity (TA), total soluble solids (TSS), moisture and fruit color at five different stages of ripening. The fruits were harvested at five different, stages RS1, RS2, RS3, RS4, and RS5 corresponding to 12, 14, 16, 18, and 20 weeks after anthesis, respectively. Significant differences were found at different stages of ripening. The pH of the fruit decreased significantly (P < 0.05), whereas TA, moisture, and TSS increased significantly (P < 0.05) during the ripening process. The redness (a*) and yellowness (b*) values of fruit color both increased significantly (P < 0.05), whereas
    lightness (L*) varied. The total phenol content TPC, TFC, FRAP, DPPH and ABTS values increased significantly (P < 0.05) with the ripening process. Sensory evaluation based on the color, sweetness, sourness, flavor, and overall acceptance for the last three maturity stages was also performed. RS5 had a better score than RS3 or RS4. The results showed the important role of the ripening stage in increasing the antioxidant content of papaya fruits.
    Matched MeSH terms: Benzothiazoles
  18. Fulltext Multivariate statistical analysis of antioxidants in dates (Phoenix dactylifera)
    Abbas, F.M.A., Foroogh, B., Liong, M.T., Azhar, M.E.
    International Food Research Journal, 2008;15(2):193-200.
    MyJurnal
    Four types of soft dates (SD), three types of semi-dried dates (SDD) and one type of dried dates (DD) were used in this study. The antioxidant activities were assessed using TEAC method (ABTS assay) and the ferric reducing/antioxidant power method (FRAP assay), while total phenolic content (TPC) and total flavonoid content (TFC) were measured using Folin-Ciocalteau and aluminum chloride colorimetric methods. Multivariate analysis of variance (MANOVA), discriminant analysis (DA) and principal component analysis (PCA) were used to analyze the data. MANOVA showed a strong significant difference between the eight types of dates. DA identified the relative contribution of each parameter in distinguishing the dates. DA also identified two functions responsible for discriminating the dates and showed the difference between different types of dates. The first function distinguished DD from other types of dates, whilst the second function discriminated SD and SDD, affording 100% correct assignation. PCA identified only one component responsible for explaining 98.85% of the total variance in antioxidant data. It is suggested that the TEAC method and the quantitative determination of TPC and TFC was suitable for differentiation of dates and quality control.
    Matched MeSH terms: Benzothiazoles
  19. Fulltext Evaluation of β-Cyclodextrin masking effect on the bitterness of Angelwing Clam (Pholas Orientalis) Hydrolysate
    Normah, I., Nurul Fasihah, R.
    International Food Research Journal, 2017;24(4):1500-1506.
    MyJurnal
    Angelwing clam (Pholas orientalis) hydrolysate was prepared by hydrolysis using bromelain. The hydrolysate named as bromelain hydrolysate (BH) was then treated with β-cyclodextrin in the ratio of 1:0.8 (v/w) by physical mixing and kneading methods producing the physical mixed hydrolysate (PMH) and kneaded method hydrolysate (KMH), respectively. The masking effect of β-cyclodextrin on bitterness was evaluated based on sensory analysis, amino acid analysis and determination of flavor compound by gas chromatography- mass spectrometry (GC-MS) and field emission scanning electron microscope (FESEM). Sensory analysis showed that KMH has least bitter taste compared to BH. Amino acids analysis showed that hydrophobic amino acids content that contributed to the bitter taste were lower in KMH and PMH compared to BH. GC-MS analysis also showed that benzothiazole compounds were present in KMH. The absence of benzene, 1-phenyl-4-2-(2-cyano-2-phenylethyl) in KMH and PMH indicated that phenylalanine in BH had been masked by β-cyclodextrin. FESEM showed that the new solid phase formed by kneading method has a crystal structure which was completely different from the original morphology of BH and β-cyclodextrin. Therefore, the bitterness in BH had successfully been masked by β-cyclodextrin, thus indicates its potential to be used as food ingredient..
    Matched MeSH terms: Benzothiazoles
  20. Fulltext Antioxidant activity of winter melon (Benincasa Hispida) seeds using conventional soxhlet extraction technique
    Mandana, B., Russly, A.R., Farah, S.T., Noranizan, M.A., Zaidul, I.S., Ali. G.
    International Food Research Journal, 2012;19(1):229-234.
    MyJurnal
    In this study, the effect of different solvent including ethanol, n-hexane and ethyl acetate on antioxidant
    activity and total phenolic content (TPC) of winter melon (Benincasa hispida) seeds extract was investigated using conventional Soxhlet extraction (CSE). DPPH and ABTS scavenging activity and TPC results indicated that the seed extracts obtained using ethanol possessed the highest antioxidant activity and followed by ethyl acetate and n-hexane. By considering obtained results, it was clear that there was a high positive correlation between TPC and antioxidant activity. Linoleic acid forms a significant percentage of unsaturated fatty acids of the seed extract (60.6%). It is well known that essential fatty acids including linoleic acid and linolenic acid which are detected in extracts play important roles in preventing many disease and abnormal differentiation problems. B. hispida seeds are potential source of natural antioxidant compounds to replace synthetic antioxidants.
    Matched MeSH terms: Benzothiazoles
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links