Displaying publications 41 - 60 of 178 in total

Abstract:
Sort:
  1. Fulltext Supercritical carbon dioxide extraction of seed oil from winter melon (Benincasa hispida) and its antioxidant activity and fatty acid composition
    Bimakr M, Rahman RA, Taip FS, Adzahan NM, Sarker MZ, Ganjloo A
    Molecules, 2013 Jan 15;18(1):997-1014.
    PMID: 23322066 DOI: 10.3390/molecules18010997
    In the present study, supercritical carbon dioxide (SC-CO(2)) extraction of seed oil from winter melon (Benincasa hispida) was investigated. The effects of process variables namely pressure (150-300 bar), temperature (40-50 °C) and dynamic extraction time (60-120 min) on crude extraction yield (CEY) were studied through response surface methodology (RSM). The SC-CO(2) extraction process was modified using ethanol (99.9%) as co-solvent. Perturbation plot revealed the significant effect of all process variables on the CEY. A central composite design (CCD) was used to optimize the process conditions to achieve maximum CEY. The optimum conditions were 244 bar pressure, 46 °C temperature and 97 min dynamic extraction time. Under these optimal conditions, the CEY was predicted to be 176.30 mg-extract/g-dried sample. The validation experiment results agreed with the predicted value. The antioxidant activity and fatty acid composition of crude oil obtained under optimized conditions were determined and compared with published results using Soxhlet extraction (SE) and ultrasound assisted extraction (UAE). It was found that the antioxidant activity of the extract obtained by SC-CO(2) extraction was strongly higher than those obtained by SE and UAE. Identification of fatty acid composition using gas chromatography (GC) showed that all the extracts were rich in unsaturated fatty acids with the most being linoleic acid. In contrast, the amount of saturated fatty acids extracted by SE was higher than that extracted under optimized SC-CO(2) extraction conditions.
    Matched MeSH terms: Picrates/chemistry
  2. Fulltext Impact of organic and inorganic fertilizers application on the phytochemical and antioxidant activity of Kacip Fatimah (Labisia pumila Benth)
    Ibrahim MH, Jaafar HZ, Karimi E, Ghasemzadeh A
    Molecules, 2013 Sep 05;18(9):10973-88.
    PMID: 24013410 DOI: 10.3390/molecules180910973
    A study was conducted to compare secondary metabolites and antioxidant activity of Labisia pumila Benth (Kacip Fatimah) in response to two sources of fertilizer [i.e., organic (chicken dung; 10% N:10% P₂O₅:10% K₂O) and inorganic fertilizer (NPK green; 15% N, 15% P₂O₅, 15% K₂O)] under different N rates of 0, 90, 180 and 270 kg N/ha. The experiment was arranged in a randomized complete block design replicated three times. At the end of 15 weeks, it was observed that the application of organic fertilizer enhanced the production of total phenolics, flavonoids, ascorbic acid, saponin and gluthathione content in L. pumila, compared to the use of inorganic fertilizer. The nitrate content was also reduced under organic fertilization. The application of nitrogen at 90 kg N/ha improved the production of secondary metabolites in Labisia pumila. Higher rates in excess of 90 kg N/ha reduced the level of secondary metabolites and antioxidant activity of this herb. The DPPH and FRAP activity was also highest at 90 kg N/ha. The results indicated that the use of chicken dung can enhance the production of secondary metabolites and improve antioxidant activity of this herb.
    Matched MeSH terms: Picrates/chemistry
  3. Fulltext Antioxidative Potential of a Streptomyces sp. MUM292 Isolated from Mangrove Soil
    Tan LT, Chan KG, Chan CK, Khan TM, Lee LH, Goh BH
    Biomed Res Int, 2018;2018:4823126.
    PMID: 29805975 DOI: 10.1155/2018/4823126
    Mangrove derived microorganisms constitute a rich bioresource for bioprospecting of bioactive natural products. This study explored the antioxidant potentials of Streptomyces bacteria derived from mangrove soil. Based on 16S rRNA phylogenetic analysis, strain MUM292 was identified as the genus Streptomyces. Strain MUM292 showed the highest 16S rRNA gene sequence similarity of 99.54% with S. griseoruber NBRC12873T. Furthermore, strain MUM292 was also characterized and showed phenotypic characteristics consistent with Streptomyces bacteria. Fermentation and extraction were performed to obtain the MUM292 extract containing the secondary metabolites of strain MUM292. The extract displayed promising antioxidant activities, including DPPH, ABTS, and superoxide radical scavenging and also metal-chelating activities. The process of lipid peroxidation in lipid-rich product was also retarded by MUM292 extract and resulted in reduced MDA production. The potential bioactive constituents of MUM292 extract were investigated using GC-MS and preliminary detection showed the presence of pyrazine, pyrrole, cyclic dipeptides, and phenolic compound in MUM292 extract. This work demonstrates that Streptomyces MUM292 can be a potential antioxidant resource for food and pharmaceutical industries.
    Matched MeSH terms: Picrates/metabolism
  4. 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
  5. Antioxidant and gastroprotective activities of Andrographis paniculata (Hempedu Bumi) in Sprague Dawley rats
    Wasman SQ, Mahmood AA, Chua LS, Alshawsh MA, Hamdan S
    Indian J Exp Biol, 2011 Oct;49(10):767-72.
    PMID: 22013743
    Antioxidant and gastroprotective activities of aqueous and ethanolic extract of Andrographis paniculata leaves in rats have been reported. Sprague Dawley rats, 6 per group were used and rats in groups 1 to 6 were pretreated with (0.25% w/v) carboxymethyl cellulose (negative control, 5 ml/kg), 20 mg/kg omeprazole (positive control), (250 mg/kg and 500 mg/kg) of aqueous leaf extracts (APLAE) and (250 and 500 mg/kg) of ethanol leaf extracts (APLEE) respectively. Animals were orally administered with 95% ethanol (5 ml/kg) 60 min after their pretreatments. Rats were sacrificed 1 h after treatment and gastric contents were collected to measure pH and mucous weight. Stomach was analyzed for gross and histological changes. Ulcer control group showed extensive lesions of gastric mucosal layer, whereas rats pretreated with omeprazole, 250 and 500 mg/kg of APLAE showed significant and dose dependent reduction in gastric lesions with increased pH and mucus content of stomach. Rats pretreated with 250 or 500 mg/kg of APLEE showed significantly better inhibition of gastric mucosal lesions. Further, the in vitro antioxidant studies using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay showed that ethanol extracts have superior free radical scavenging activity with IC50 value = 10.9 than aqueous extracts with IC50 value = 24.65. Results of this study showed that pretreatment with ethonolic extract of A. paniculata ethanolic provided significant protection against gastric ulcer by regulating of pH, mucous production and antioxidant property.
    Matched MeSH terms: Picrates/chemistry
  6. Fulltext Antioxidant activity of melon fruit peel extracts
    Sarini Ahmad Wakid, Hamira Azrin binti Harun
    Journal of Academia Universiti Teknologi MARA Negeri Sembilan, 2020;8(1):53-57.
    MyJurnal
    The present study was conducted to evaluate the antioxidant activity of peel extract from three types of
    melon, Cucumis melo var cantalupensis, Cucumis melo var inodorus and Citrullus lanatus in family
    Curcurbitaceae. The extract was prepared with methanol respectively. 1,1-diphenyl-2-picrylhydrazyl
    (DPPH) assay were used to study their antioxidant activity. The extracts were compared with commercial
    antioxidant, butylated hydroxytoluene (BHT). The highest scavenging effect from peel extract was
    presented by Cucumis melo var inodorus with the value of 52.7 ± 9.1µg/ml (IC50 = 4.61). BHT showed
    the lowest IC50 value 1.71 with the scavenging activity 90.0 ± 1.7µg/ml. Low IC50 value will indicates the
    strong ability of the extracts to act as DPPH scavenger.

    Matched MeSH terms: Picrates
  7. Fulltext Nutritional content and in vitro antioxidant potential of Garcinia atroviridis (Asam gelugor) leaves and fruits
    Nursakinah I, Zulkhairi HA, Norhafizah M, Hasnah B, Zamree MS, Farrah SI, et al.
    Malays J Nutr, 2012 Dec;18(3):363-71.
    PMID: 24568077 MyJurnal
    The objective of this study was to determine antioxidant potential of Garcinia atroviridis leaves and fruits extracts in vitro.
    Matched MeSH terms: Picrates/chemistry
  8. Fulltext Antidiarrheal, antimicrobial and antioxidant potentials of methanol extract of Colocasia gigantea Hook. f. leaves: evidenced from in vivo and in vitro studies along with computer-aided approaches
    Alam S, Rashid MA, Sarker MMR, Emon NU, Arman M, Mohamed IN, et al.
    BMC Complement Med Ther, 2021 Apr 12;21(1):119.
    PMID: 33845836 DOI: 10.1186/s12906-021-03290-6
    BACKGROUND: Colocasia gigantea, locally named as kochu is well-known due to its various healing power. This research is to investigate the antidiarrheal, antimicrobial and antioxidant possibilities of the methanol soluble extract of Colocasia gigantea.

    METHODS: The antidiarrheal investigation was performed by using in vivo castor oil-induced diarrheal method whereas in vitro antimicrobial and antioxidant investigation have been implemented by disc diffusion and DPPH scavenging method respectively. Moreover, in silico studies were followed by molecular docking analysis of several secondary metabolites that were appraised with Schrödinger-Maestro v11.1 and Biovia Discovery Studio.

    RESULTS: The induction of plant extract (200 and 400 mg/kg, b.w, p.o) has minimized the castor oil mediated diarrhea by 16.96% (p 

    Matched MeSH terms: Picrates
  9. Free radical scavenging, antidiarrheal and anthelmintic activity of Pistia stratiotes L. extracts and its phytochemical analysis
    Bin Karim MF, Imam H, Sarker MM, Uddin N, Hasan N, Paul N, et al.
    Pak J Pharm Sci, 2015 May;28(3):915-20.
    PMID: 26004725
    In this phyto-pharmacological screening of Pistia stratiotes L leaf and root extracts each separately in two different solvents demonstrated its potential medicinal value. Apparent antioxidant value is demonstrated by DPPH, Nitric oxide scavenging and Ferric ion reducing method. Additionally, total flavonoid and phenolic compounds were measured. The leaf methanolic extract scavenged both nitric oxide (NO) and DPPH radical with a dose dependent manner. But the pet ether fraction of root was found to have highest efficacy in Fe(3±) reducing power assay. Flavonoid was found to contain highest in the pet ether fraction of root (411.35mg/g) in terms of quercetin equivalent, similarly highest amount (34.96mg/g) of total phenolic compounds (assayed as gallic acid equivalents) were found to contain in the same fraction. The methanolic fractions appeared less cytotoxic compared to pet ether extracts. The plant extracts caused a dose dependent decrease in faecal droppings in both castor oil and magnesium sulphate induced diarrhea, where as leaf extracts in each solvent appeared most effective. Also, the plant extracts showed anthelmintic activity in earthworm by inducing paralysis and death in a dose dependent manner. At highest doses (50 mg/ml) all fractions were almost effective as the positive control piperazine citrate (10 mg/ml). Thus, besides this cytotoxic effect it's traditional claim for therapeutic use can never be overlooked.
    Matched MeSH terms: Picrates/metabolism
  10. Fulltext Free radical scavenging, antimicrobial and immunomodulatory activities of Orthosiphon stamineus
    Alshawsh MA, Abdulla MA, Ismail S, Amin ZA, Qader SW, Hadi HA, et al.
    Molecules, 2012;17(5):5385-95.
    PMID: 22569417 DOI: 10.3390/molecules17055385
    Orthosiphon stamineus is considered an important traditional folk medicine. In this study ethanol and aqueous extracts of O. stamineus were evaluated in vitro for their antioxidant, antimicrobial as well as for their immunomodulatory properties on human peripheral blood mononuclear cells (PBMCs). The DPPH radical scavenging method was used for the determination of antioxidant activity, while the antibacterial efficacy was investigated by both disc diffusion method and Minimum Inhibitory Concentration (MIC) against four bacterial strains (Gram-positive and Gram-negative). Furthermore, the immunomodulatory potential of the extracts was investigated through the MTT assay. Aqueous extract of O. stamineus exhibited significant free radical scavenging activity with IC₅₀ 50 9.6 µg/mL, whereas the IC₅₀ for the ethanol extract was 21.4 µg/mL. The best antimicrobial activity was shown by the aqueous extract of O. stamineus against Staphylococcus aureus, with inhibition zone of 10.5 mm and MIC value 1.56 mg/mL. Moreover, the results observed from the MTT assay showed that both plant extracts stimulated the PBMCs proliferation in vitro in a concentration-dependent manner, but the aqueous extract has remarkable activity against PBMCs. These findings indicate that O. stamineus showed high antioxidant activity and may be considered as an immunomodulatory agent.
    Matched MeSH terms: Picrates/antagonists & inhibitors
  11. Synthesis, Antioxidant and In-Silico Studies of Potent Urease Inhibitors: N-(4-{[(4-Methoxyphenethyl)-(substituted)amino]sulfonyl}phenyl)acetamides
    Abbasi MA, Raza H, Rehman AU, Siddiqui SZ, Nazir M, Mumtaz A, et al.
    Drug Res (Stuttg), 2019 Feb;69(2):111-120.
    PMID: 30086567 DOI: 10.1055/a-0654-5074
    In this study, a new series of sulfonamides derivatives was synthesized and their inhibitory effects on DPPH and jack bean urease were evaluated. The in silico studies were also applied to ascertain the interactions of these molecules with active site of the enzyme. Synthesis was initiated by the nucleophilic substitution reaction of 2-(4-methoxyphenyl)-1-ethanamine (1: ) with 4-(acetylamino)benzenesulfonyl chloride (2): in aqueous sodium carbonate at pH 9. Precipitates collected were washed and dried to obtain the parent molecule, N-(4-{[(4-methoxyphenethyl)amino]sulfonyl}phenyl)acetamide (3): . Then, this parent was reacted with different alkyl/aralkyl halides, (4A-M: ), using dimethylformamide (DMF) as solvent and LiH as an activator to produce a series of new N-(4-{[(4-methoxyphenethyl)-(substituted)amino]sulfonyl}phenyl)acetamides (5A-M: ). All the synthesized compounds were characterized by IR, EI-MS, 1H-NMR, 13C-NMR and CHN analysis data. All of the synthesized compounds showed higher urease inhibitory activity than the standard thiourea. The compound 5 F: exhibited very excellent enzyme inhibitory activity with IC50 value of 0.0171±0.0070 µM relative to standard thiourea having IC50 value of 4.7455±0.0546 µM. Molecular docking studies suggested that ligands have good binding energy values and bind within the active region of taget protein. Chemo-informatics properties were evaluated by computational approaches and it was found that synthesized compounds mostly obeyed the Lipinski' rule.
    Matched MeSH terms: Picrates/metabolism; Picrates/chemistry
  12. Fulltext Effects of squid ink as edible coating on squid sp. (Loligo duvauceli) spoilage during chilled storage
    Karim, N.U., Sadzali, N.L., Hassan, M.
    International Food Research Journal, 2016;23(5):1895-1901.
    MyJurnal
    The effects of squid ink at concentration of 0.10 and 0.25% on the total bacteria count and
    chemical spoilage indicator; total volatile basis nitrogen (TVBN) and trimethylamine (TMA)
    of squid (Loligo duvauceli) were analysed. The analysis were performed at interval of 5 days
    during 15 days of chilled storage (4°C). This studies also investigate the antioxidant capacity
    of the squid ink. The melanin-free squid ink were subjected to ferric reducing power (FRAP)
    and 2,2-diphenyl-1-picrylhydrazyl (DPPH) analysis. The FRAP values found in squid ink were
    0.04±0.01 µmole TE g-1 meanwhile DPPH values were recorded at 0.81±0.00 µmole TE g-1.
    The squid ink at both 0.10 and 0.25% concentration showed a significantly (p
    Matched MeSH terms: Picrates
  13. A novel high throughput method based on the DPPH dry reagent array for determination of antioxidant activity
    Musa KH, Abdullah A, Kuswandi B, Hidayat MA
    Food Chem, 2013 Dec 15;141(4):4102-6.
    PMID: 23993591 DOI: 10.1016/j.foodchem.2013.06.112
    A stable chromogenic radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) is commonly used for the determination of antioxidant activity. In this paper, DPPH was dried into 96 well microplate to produce DPPH dry reagent array plate, based on which the highly sensitive and high throughput determination of antioxidant activities was achieved. The spectrophotometric characterization of the microplate containing dried or fresh DPPH free radicals was reported. The response of the DPPH dry reagent array towards different standard antioxidants was studied. The reaction for DPPH in fresh or dry reagent array with Trolox was reported and compared. The DPPH dry reagent array was used to study the antioxidant activity of banana, green tea, pink guava, and honeydew and the results were compared to the samples reacted with freshly prepared DPPH. The proposed method is comparable to the classical DPPH method, more convenient, simple to operate with minimal solvent required and excellent sensitivity.
    Matched MeSH terms: Picrates/chemistry*
  14. Fulltext Ultrasound-assisted extraction of antioxidants in Misai Kucing (Orthosiphon stamineus)
    Ho SK, Tan CP, Thoo YY, Abas F, Ho CW
    Molecules, 2014 Aug 19;19(8):12640-59.
    PMID: 25153876 DOI: 10.3390/molecules190812640
    Ultrasound-assisted extraction (UAE) with ethanol was used to extract the compounds responsible for the antioxidant activities of Misai Kucing (Orthosiphon stamineus). Response surface methodology (RSM) was used to optimize four independent variables: ethanol concentration (%), amplitude (%), duty cycle (W/s) and extraction time (min). Antioxidant compounds were determined by total phenolic content and total flavonoid content to be 1.4 g gallic acid equivalent/100 g DW and 45 g catechin equivalent/100 g DW, respectively. Antioxidant activities were evaluated using the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+) radical scavenging capacity assay and the 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging capacity assay to be 1,961.3 and 2,423.3 µmol Trolox Equivalent Antioxidant Capacity (TEAC)/100 g DW, respectively. Based on the optimal conditions, experimental values were reported to be close to the predicted value by RSM modeling (p>0.05), indicating the suitability of UAE for extracting the antioxidants of Misai Kucing. Rosmarinic acid, kaempferol-rutinoside and sinesetine were identified by high performance liquid chromatography-mass spectrometry.
    Matched MeSH terms: Picrates/chemistry
  15. 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: Picrates
  16. Comparative study of antioxidant activities and total phenolic content of selected edible wild mushrooms
    Yim HS, Chye FY, Lee MY, Matanjun P, How SE, Ho CW
    Int J Med Mushrooms, 2011;13(3):245-55.
    PMID: 22135876
    The present study aims to assess the antioxidant activities (AOA) and total phenolic content (TPC) of water extracts of selected edible wild mushrooms: Pleurotus porrigens, Schizophyllum commune, Hygrocybe conica, and Lentinus ciliatus. The AOA were evaluated against DPPH radical and ABTS radical cation scavenging ability, ferric-reducing antioxidant power (FRAP) and beta-carotene-linoleate bleaching (beta-CB) assays, and the Folin-Ciocalteu method for TPC. BHA was used as reference. P. porrigens showed significantly higher (p < 0.05) DPPH* scavenging ability (90.78 +/- 0.30%) and FRAP (6.37 +/- 0.22 mM FE/100g), while Sch. commune showed significantly higher (p < 0.05) ABTS*+ inhibition activity (94.96 +/- 0.70%) and beta-CB inhibition activity (94.18 +/- 0.17%), respectively. TPC was found in a descending order of P. poriggens > L. ciliatus = Pleurotus ostreatus (cultivated) > H. conica = Sch. commune. Positive correlation was observed between the AOA and TPC. When compared to BHA (2 mM), P. porrigens showed significantly higher (p < 0.05) DPPH* scavenging ability and reducing power, while Sch. commune showed comparable DPPH* scavenging ability and ABTS*+ inhibition activity. All the mushrooms have better ABTS*+ inhibition activity than BHA (1 mM). The beta-CB inhibition activity of BHA was significantly higher than those of edible wild mushrooms. The water extracts of edible wild mushrooms showed potent antioxidant activities compared to BHA to a certain extent.
    Matched MeSH terms: Picrates/metabolism
  17. Fulltext Bioactive compounds and biological activities of Jatropha curcas L. kernel meal extract
    Oskoueian E, Abdullah N, Ahmad S, Saad WZ, Omar AR, Ho YW
    Int J Mol Sci, 2011;12(9):5955-70.
    PMID: 22016638 DOI: 10.3390/ijms12095955
    Defatted Jatropha curcas L. (J. curcas) seed kernels contained a high percentage of crude protein (61.8%) and relatively little acid detergent fiber (4.8%) and neutral detergent fiber (9.7%). Spectrophotometric analysis of the methanolic extract showed the presence of phenolics, flavonoids and saponins with values of 3.9, 0.4 and 19.0 mg/g DM, respectively. High performance liquid chromatography (HPLC) analyses showed the presence of gallic acid and pyrogallol (phenolics), rutin and myricetin (flavonoids) and daidzein (isoflavonoid). The amount of phorbol esters in the methanolic extract estimated by HPLC was 3.0 ± 0.1 mg/g DM. Other metabolites detected by GC-MS include: 2-(hydroxymethyl)-2 nitro-1,3-propanediol, β-sitosterol, 2-furancarboxaldehyde, 5-(hydroxymethy) and acetic acid in the methanolic extract; 2-furancarboxaldehyde, 5-(hydroxymethy), acetic acid and furfural (2-furancarboxaldehyde) in the hot water extract. Methanolic and hot water extracts of kernel meal showed antimicrobial activity against both Gram positive and Gram negative pathogenic bacteria (inhibition range: 0-1.63 cm) at the concentrations of 1 and 1.5 mg/disc. Methanolic extract exhibited antioxidant activities that are higher than hot water extract and comparable to β-carotene. The extracts tended to scavenge the free radicals in the reduction of ferric ion (Fe(3+)) to ferrous ion (Fe(2+)). Cytotoxicity assay results indicated the potential of methanolic extract as a source of anticancer therapeutic agents toward breast cancer cells.
    Matched MeSH terms: Picrates/antagonists & inhibitors; Picrates/metabolism; Picrates/chemistry
  18. Fulltext Optimization for extraction on total phenolic content and radical scavenging capacity of Henna (Lawsonia inermis) stems using response surface methodology
    Tan, M. C., Tan, C. P., Khoo, H. E., Ho, C. W.
    International Food Research Journal, 2014;21(2):789-794.
    MyJurnal
    This study aimed to optimise potential extraction conditions using response surface methodology (RSM) for yielding maximum levels of total phenolic content (TPC) and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) scavenging capacity of henna (Lawsonia inermis) stems. The ranges for selected independent variables, namely acetone concentration (20−90%, v/v), extraction time (10−90 min), and extraction temperature (25−45°C) were identified by screening tests. Optimum conditions obtained for extraction of TPC were 47.0% acetone, extraction time of 47.6 min and extraction temperature of 37.3oC. The result also showed that 75.8% acetone, extraction time of 26.2 min and extraction temperature of 41oC yielded the highest DPPH• scavenging capacity. The optimized extraction conditions have resulted in TPC and DPPH• scavenging capacity of 5232.4 mg GAE/100 g DW and 6085.7 mg TE/100 g DW, respectively which similar to the predicted values. Therefore, RSM has successfully optimized the extraction conditions for TPC and radical scavenging capacity of henna stems.
    Matched MeSH terms: Picrates
  19. 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: Picrates
  20. Fulltext Synthesis, evaluation of antioxidant activity and crystal structure of 2,4-dimethylbenzoylhydrazones
    Taha M, Ismail NH, Jamil W, Yousuf S, Jaafar FM, Ali MI, et al.
    Molecules, 2013 Sep 05;18(9):10912-29.
    PMID: 24013406 DOI: 10.3390/molecules180910912
    2,4-Dimethylbenzoylhydrazones 1-30 were synthesized by condensation reactions of 2,4-dimethylbenzoylhydrazide with various aromatic aldehydes and characterized. The assigned structures of compounds 10, 15 and 22 were further supported by single-crystal X-ray diffraction data. The synthesized compounds were evaluated for their in vitro DPPH radical scavenging activity. They exerted varying degree of scavenging activity toward DPPH radical with IC₅₀ values between 25.6-190 µM. Compounds 1, 4, 2, 3, 7, and 6 have IC₅₀ values of 25.6, 28.1, 29.3, 29.8, 30.0 and 30.1 µM respectively, showing better activity than an n-propyl gallate standard (IC₅₀ value = 30.30 µM). For super oxide anion scavenging activity compounds 1, 2 and 3 with IC₅₀ values of 98.3, 102.6, and 105.6, respectively, also showed better activity than the n-propyl gallate standard (IC₅₀ value = 106.34 µM).
    Matched MeSH terms: Picrates/chemistry
Related Terms
Filters
Contact Us

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

External Links