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  1. Functionalized Carbon Nano-scale Drug Delivery Systems From Biowaste Sago Bark For Cancer Cell Imaging
    Abdul Manaf SA, Hegde G, Mandal UK, Wui TW, Roy P
    Curr Drug Deliv, 2017;14(8):1071-1077.
    PMID: 27745545 DOI: 10.2174/1567201813666161017130612
    BACKGROUND: Nano-scale carbon systems are emerging alternatives in drug delivery and bioimaging applications of which they gradually replace the quantum dots characterized by toxic heavy metal content in the latter application.

    OBJECTIVE: The work intended to use carbon nanospheres synthesized from biowaste Sago bark for cancer cell imaging applications.

    METHODS: This study synthesised carbon nanospheres from biowaste Sago bark using a catalyst-free pyrolysis technique. The nanospheres were functionalized with fluorescent dye coumarin-6 for cell imaging. Fluorescent nanosytems were characterized by field emission scanning electron microscopy-energy dispersive X ray, photon correlation spectroscopy and fourier transform infrared spectroscopy techniques.

    RESULTS: The average size of carbon nanospheres ranged between 30 and 40 nm with zeta potential of -26.8 ± 1.87 mV. The percentage viability of cancer cells on exposure to nanospheres varied from 91- 89 % for N2a cells and 90-85 % for A-375 cells respectively. Speedy uptake of the fluorescent nanospheres in both N2a and A-375 cells was observed within two hours of exposure.

    CONCLUSION: Novel fluorescent carbon nanosystem design following waste-to-wealth approach exhibited promising potential in cancer cell imaging applications.

    Matched MeSH terms: Carbon/chemistry; Fluorescent Dyes/chemistry; Arecaceae/chemistry*; Nanospheres/chemistry*
  2. Synthesis: Small library of hybrid scaffolds of benzothiazole having hydrazone and evaluation of their β-glucuronidase activity
    Taha M, Arbin M, Ahmat N, Imran S, Rahim F
    Bioorg Chem, 2018 04;77:47-55.
    PMID: 29331764 DOI: 10.1016/j.bioorg.2018.01.002
    Due to the great biological importance of β-glucuronidase inhibitors, here in this study, we have synthesized a library of novel benzothiazole derivatives (1-30), characterized by different spectroscopic methods and evaluated for β-glucuronidase inhibitory potential. Among the series sixteen compounds i.e.1-6, 8, 9, 11, 14, 15, 20-23 and 26 showed outstanding inhibitory potential with IC50 value ranging in between 16.50 ± 0.26 and 59.45 ± 1.12 when compared with standard d-Saccharic acid 1,4-lactone (48.4 ± 1.25 µM). Except compound 8 and 23 all active analogs showed better potential than the standard. Structure activity relationship has been established.
    Matched MeSH terms: Glycoproteins/chemistry; Hydrazones/chemistry; Benzothiazoles/chemistry; Small Molecule Libraries/chemistry
  3. Pre-dispersed organo-montmorillonite (organo-MMT) nanofiller: Morphology, cytocompatibility and impact on flexibility, toughness and biostability of biomedical ethyl vinyl acetate (EVA) copolymer
    Osman AF, M Fitri TF, Rakibuddin M, Hashim F, Tuan Johari SAT, Ananthakrishnan R, et al.
    Mater Sci Eng C Mater Biol Appl, 2017 May 01;74:194-206.
    PMID: 28254285 DOI: 10.1016/j.msec.2016.11.137
    Polymer-clay based nanocomposites are among the attractive materials to be applied for various applications, including biomedical. The incorporation of the nano sized clay (nanoclay) into polymer matrices can result in their remarkable improvement in mechanical, thermal and barrier properties as long as the nanofillers are well exfoliated and dispersed throughout the matrix. In this work, exfoliation strategy through pre-dispersing process of the organically modified montmorillonite (organo-MMT) nanofiller was done to obtain ethyl vinyl acetate (EVA) nanocomposite with improved flexibility, toughness, thermal stability and biostability. Our results indicated that the degree of organo-MMT exfoliation affects its cytotoxicity level and the properties of the resulting EVA nanocomposite. The pre-dispersed organo-MMT by ultrasonication in water possesses higher degree of exfoliation as compared to its origin condition and significantly performed reduced cytotoxicity level. Beneficially, this nanofiller also enhanced the EVA flexibility, thermal stability and biostability upon the in vitro exposure. We postulated that these were due to plasticizing effect and enhanced EVA-nanofiller interactions contributing to more stable chemical bonds in the main copolymer chains. Improvement in copolymer flexibility is beneficial for close contact with human soft tissue, while enhancement in toughness and biostability is crucial to extend its life expectancy as insulation material for implantable device.
    Matched MeSH terms: Bentonite/chemistry*; Polymers/chemistry*; Vinyl Compounds/chemistry*; Nanocomposites/chemistry*
  4. Fulltext Compositional analyses of white, brown and germinated forms of popular Malaysian rice to offer insight into the growing diet-related diseases
    Abubakar B, Yakasai HM, Zawawi N, Ismail M
    J Food Drug Anal, 2018 04;26(2):706-715.
    PMID: 29567241 DOI: 10.1016/j.jfda.2017.06.010
    Diet-related metabolic diseases, and especially obesity, are metabolic disorders with multifactorial aetiologies. Diet has been a cornerstone in both the aetiology and management of this metabolic disorders. Rice, a staple food for over half of the world's population, could be exploited as part of the solution to check this menace which has been skyrocketing in the last decade. The present study investigated nine forms of rice from three widely grown Malaysian rice cultivars for in vitro and in vivo (glycaemic index and load) properties that could translate clinically into a lower predisposition to diet-related diseases. The germinated brown forms of MRQ 74 and MR 84 rice cultivars had high amylose content percentages (25.7% and 25.0%), high relative percentage antioxidant scavenging abilities of 85.0% and 91.7%, relatively low glycaemic indices (67.6 and 64.3) and glycaemic load (32.3 and 30.1) values, and modest glucose uptake capabilities of 33.69% and 31.25%, respectively. The results show that all things being equal, rice cultivars that are germinated and high in amylose content when compared to their white and low amylose counterparts could translate into a lower predisposition to diet-related diseases from the dietary point of view in individuals who consume this cereal as a staple food.
    Matched MeSH terms: Antioxidants/chemistry; Plant Extracts/chemistry*; Oryza/chemistry*; Seeds/chemistry
  5. Fulltext The Marine Natural Product Manzamine A Inhibits Cervical Cancer by Targeting the SIX1 Protein
    Karan D, Dubey S, Pirisi L, Nagel A, Pina I, Choo YM, et al.
    J Nat Prod, 2020 Feb 28;83(2):286-295.
    PMID: 32022559 DOI: 10.1021/acs.jnatprod.9b00577
    Natural products remain an important source of drug leads covering unique chemical space and providing significant therapeutic value for the control of cancer and infectious diseases resistant to current drugs. Here, we determined the antiproliferative activity of a natural product manzamine A (1) from an Indo-Pacific sponge following various in vitro cellular assays targeting cervical cancer (C33A, HeLa, SiHa, and CaSki). Our data demonstrated the antiproliferative effects of 1 at relatively low and non-cytotoxic concentrations (up to 4 μM). Mechanistic investigations confirmed that 1 blocked cell cycle progression in SiHa and CaSki cells at G1/S phase and regulated cell cycle-related genes, including restoration of p21 and p53 expression. In apoptotic assays, HeLa cells showed the highest sensitivity to 1 as compared to other cell types (C33A, SiHa, and CaSki). Interestingly, 1 decreased the levels of the oncoprotein SIX1, which is associated with oncogenesis in cervical cancer. To further investigate the structure-activity relationship among manzamine A (1) class with potential antiproliferative activity, molecular networking facilitated the efficient identification, dereplication, and assignment of structures from the manzamine class and revealed the significant potential in the design of optimized molecules for the treatment of cervical cancer. These data suggest that this sponge-derived natural product class warrants further attention regarding the design and development of novel manzamine analogues, which may be efficacious for preventive and therapeutic treatment of cancer. Additionally, this study reveals the significance of protecting fragile marine ecosystems from climate change-induced loss of species diversity.
    Matched MeSH terms: Biological Products/chemistry; Carbazoles/chemistry; Uterine Cervical Neoplasms/chemistry; Homeodomain Proteins/chemistry
  6. Integrated adsorption-solar photocatalytic membrane reactor for degradation of hazardous Congo red using Fe-doped ZnO and Fe-doped ZnO/rGO nanocomposites
    Ong CB, Mohammad AW, Ng LY
    Environ Sci Pollut Res Int, 2019 Nov;26(33):33856-33869.
    PMID: 29943245 DOI: 10.1007/s11356-018-2557-2
    In this work, synergistic effect of solar photocatalysis integrated with adsorption process towards the degradation of Congo red (CR) was investigated via two different approaches using a photocatalytic membrane reactor. In the first approach, sequential treatments were conducted through the adsorption by graphene oxide (GO) and then followed by photocatalytic oxidation using Fe-doped ZnO nanocomposites (NCs). In the second approach, however, CR solution was treated by photocatalytic oxidation using Fe-doped ZnO/rGO NCs. These nanocomposites were synthesized by a sol-gel method. The NCs were characterized by X-ray diffraction (XRD), photoluminescence (PL), Fourier transmission infrared (FTIR), ultraviolet-visible (UV-vis) spectroscopy, and field emission scanning electron microscopy (FESEM). It was observed that Fe-doped ZnO could enhance the photoactivity of ZnO under solar light. When Fe-doped ZnO were decorated on GO sheets, however, this provided a surface enhancement for adsorption of organic pollutants. The photocatalytic performances using both approaches were evaluated based on the degradation of CR molecules in aqueous solution under solar irradiation. Nanofiltration (NF) performance in terms of CR residual removal from water and their fouling behavior during post-separation of photocatalysts was studied. Serious flux declined and thicker fouling layer on membrane were found in photocatalytic membrane reactor using Fe-doped ZnO/rGO NCs which could be attributed to the stronger π-π interaction between rGO and CR solution.
    Matched MeSH terms: Congo Red/chemistry*; Water Pollutants, Chemical/chemistry*; Zinc Oxide/chemistry; Nanocomposites/chemistry
  7. Electro-transformation of mefenamic acid drug: a case study of kinetics, transformation products, and toxicity
    Mussa ZH, Al-Qaim FF, Yuzir A, Latip J
    Environ Sci Pollut Res Int, 2019 Apr;26(10):10044-10056.
    PMID: 30756352 DOI: 10.1007/s11356-019-04301-3
    Poor removal of many pharmaceuticals and personal care products in sewage treatment plants leads to their discharge into the receiving waters, where they may cause negative effects for aquatic environment and organisms. In this study, electrochemical removal process has been used as alternative method for removal of mefenamic acid (MEF). For our knowledge, removal of MEF using electrochemical process has not been reported yet. Effects of initial concentration of mefenamic acid, sodium chloride (NaCl), and applied voltage were evaluated for improvement of the efficiency of electrochemical treatment process and to understand how much electric energy was consumed in this process. Removal percentage (R%) was ranged between 44 and 97%, depending on the operating parameters except for 0.1 g NaCl which was 9.1%. Consumption energy was 0.224 Wh/mg after 50 min at 2 mg/L of mefenamic acid, 0.5 g NaCl, and 5 V. High consumption energy (0.433 Wh/mg) was observed using high applied voltage of 7 V. Investigation and elucidation of the transformation products were provided by Bruker software dataAnalysis using liquid chromatography-time of flight mass spectrometry. Seven chlorinated and two non-chlorinated transformation products were investigated after 20 min of electrochemical treatment. However, all transformation products (TPs) were eliminated after 140 min. For the assessment of the toxicity, it was impacted by the formation of transformation products especially between 20 and 60 min then the inhibition percentage of E. coli bacteria was decreased after 80 min to be the lowest value.
    Matched MeSH terms: Anti-Inflammatory Agents, Non-Steroidal/chemistry*; Electrochemistry; Mefenamic Acid/chemistry*; Sodium Chloride/chemistry; Water Pollutants, Chemical/chemistry*
  8. Physicochemical profile of microbial-assisted composting on empty fruit bunches of oil palm trees
    Lim LY, Bong CP, Chua LS, Lee CT
    Environ Sci Pollut Res Int, 2015 Dec;22(24):19814-22.
    PMID: 26286798 DOI: 10.1007/s11356-015-5156-5
    This study was carried out to investigate the physicochemical properties of compost from oil palm empty fruit bunches (EFB) inoculated with effective microorganisms (EM∙1™). The duration of microbial-assisted composting was shorter (∼7 days) than control samples (2 months) in a laboratory scale (2 kg) experiment. The temperature profile of EFB compost fluctuated between 26 and 52 °C without the presence of consistent thermophilic phase. The pH of compost changed from weak acidic (pH ∼5) to mild alkaline (pH ∼8) because of the formation of nitrogenous ions such as ammonium (NH4 (+)), nitrite (NO2 (-)), and nitrate (NO3 (-)) from organic substances during mineralization. The pH of the microbial-treated compost was less than 8.5 which is important to prevent the loss of nitrogen as ammonia gas in a strong alkaline condition. Similarly, carbon mineralization could be determined by measuring CO2 emission. The microbial-treated compost could maintain longer period (∼13 days) of high CO2 emission resulted from high microbial activity and reached the threshold value (120 mg CO2-C kg(-1) day(-1)) for compost maturity earlier (7 days). Microbial-treated compost slightly improved the content of minerals such as Mg, K, Ca, and B, as well as key metabolite, 5-aminolevulinic acid for plant growth at the maturity stage of compost. Graphical Abstract Microbial-assisted composting on empty fruit bunches.
    Matched MeSH terms: Cocos/chemistry; Plant Oils/chemistry; Soil/chemistry*; Plant Components, Aerial/chemistry
  9. Fulltext Response of Cellular Innate Immunity to Cnidarian Pore-Forming Toxins
    Yap WY, Hwang JS
    Molecules, 2018 Oct 04;23(10).
    PMID: 30287801 DOI: 10.3390/molecules23102537
    A group of stable, water-soluble and membrane-bound proteins constitute the pore forming toxins (PFTs) in cnidarians. They interact with membranes to physically alter the membrane structure and permeability, resulting in the formation of pores. These lesions on the plasma membrane causes an imbalance of cellular ionic gradients, resulting in swelling of the cell and eventually its rupture. Of all cnidarian PFTs, actinoporins are by far the best studied subgroup with established knowledge of their molecular structure and their mode of pore-forming action. However, the current view of necrotic action by actinoporins may not be the only mechanism that induces cell death since there is increasing evidence showing that pore-forming toxins can induce either necrosis or apoptosis in a cell-type, receptor and dose-dependent manner. In this review, we focus on the response of the cellular immune system to the cnidarian pore-forming toxins and the signaling pathways that might be involved in these cellular responses. Since PFTs represent potential candidates for targeted toxin therapy for the treatment of numerous cancers, we also address the challenge to overcoming the immunogenicity of these toxins when used as therapeutics.
    Matched MeSH terms: Cell Membrane/chemistry; Cnidaria/chemistry; Toxins, Biological/chemistry; Pore Forming Cytotoxic Proteins/chemistry
  10. Fulltext Benzofuranyl Esters: Synthesis, Crystal Structure Determination, Antimicrobial and Antioxidant Activities
    Kumar CS, Then LY, Chia TS, Chandraju S, Win YF, Sulaiman SF, et al.
    Molecules, 2015 Sep 11;20(9):16566-81.
    PMID: 26378514 DOI: 10.3390/molecules200916566
    A series of five new 2-(1-benzofuran-2-yl)-2-oxoethyl 4-(un/substituted)benzoates 4(a-e), with the general formula of C₈H₅O(C=O)CH₂O(C=O)C₆H₄X, X = H, Cl, CH₃, OCH₃ or NO₂, was synthesized in high purity and good yield under mild conditions. The synthesized products 4(a-e) were characterized by FTIR, ¹H-, (13)C- and ¹H-(13)C HMQC NMR spectroscopic analysis and their 3D structures were confirmed by single-crystal X-ray diffraction studies. These compounds were screened for their antimicrobial and antioxidant activities. The tested compounds showed antimicrobial ability in the order of 4b < 4a < 4c < 4d < 4e and the highest potency with minimum inhibition concentration (MIC) value of 125 µg/mL was observed for 4e. The results of antioxidant activities revealed the highest activity for compound 4e (32.62% ± 1.34%) in diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, 4d (31.01% ± 4.35%) in ferric reducing antioxidant power (FRAP) assay and 4a (27.11% ± 1.06%) in metal chelating (MC) activity.
    Matched MeSH terms: Anti-Infective Agents/chemistry; Antioxidants/chemistry*; Benzofurans/chemistry*; Esters/chemistry*
  11. Fulltext Bioactive 2-(Methyldithio)Pyridine-3-Carbonitrile from Persian Shallot (Allium stipitatum Regel.) Exerts Broad-Spectrum Antimicrobial Activity
    Karunanidhi A, Ghaznavi-Rad E, Jeevajothi Nathan J, Joseph N, Chigurupati S, Mohd Fauzi F, et al.
    Molecules, 2019 Mar 13;24(6).
    PMID: 30871159 DOI: 10.3390/molecules24061003
    Antibiotic resistance is a problem that continues to challenge the healthcare sector, especially in clinically significant pathogens like methicillin-resistant Staphylococcus aureus (MRSA). Herein is described the isolation and structure elucidation of a bioactive compound from Allium stipitatum with antimicrobial activity. Crude Allium stipitatum dichloromethane extract (ASDE) was subjected to systematic purification by chromatographic procedures to afford various bioactive fractions. A fraction that exhibited anti-MRSA activity (4 µg·mL-1) was further characterized to determine the structure. The structure of the compound was elucidated as 2-(methyldithio)pyridine-3-carbonitrile (2-Medpy-3-CN). The 2-Medpy-3-CN compound, which was screened for antimicrobial activity, exhibited minimum inhibitory concentrations (MICs) in the range of 0.5 to >64 µg·mL-1 for tested bacterial species and 0.25 to 2 µg·mL-1 for Candida spp. Further studies are important to confirm the drug target and mechanism of action.
    Matched MeSH terms: Anti-Bacterial Agents/chemistry*; Nitriles/chemistry; Pyridines/chemistry*; Shallots/chemistry*
  12. Direct recovery of malate dehydrogenase from highly turbid yeast cell homogenate using dye-ligand affinity chromatography in stirred fluidized bed
    Chen KH, Lee SY, Show PL, Hong SC, Chang YK
    J Chromatogr B Analyt Technol Biomed Life Sci, 2018 Nov 15;1100-1101:65-75.
    PMID: 30292951 DOI: 10.1016/j.jchromb.2018.09.039
    Dye-ligand affinity chromatography in a stirred fluidized bed has been developed for the rapid recovery of malate dehydrogenase (MDH) from highly turbid baker's yeast cell homogenate in a single step. The most suitable dye, namely Reactive Orange 4, in its optimal immobilized concentration of 8.78 mg/mL was immobilized onto high-density STREAMLINE matrix. To further examine optimal adsorption and elution conditions, the enzyme recovery operation was carried out using unclarified cell homogenates in stirred fluidized bed system. Aiming to develop a non-specific eluent, namely NaCl, to effectively elute the MDH adsorbed, direct recovery of MDH from highly turbid cell homogenate (50% w/v) in a stirred fluidized bed adsorption system was performed. The proposed system successfully achieved a recovery yield of 73.6% and a purification factor of 73.5 in a single step by using 0.6 M NaCl as an eluent at a high liquid velocity of 200 cm/h.
    Matched MeSH terms: Azo Compounds/chemistry; Cell Extracts/chemistry*; Coloring Agents/chemistry; Sulfuric Acid Esters/chemistry
  13. Method development for analysis of proteins extracted from the leaves of Orthosiphon aristatus
    Koay SY, Gam LH
    J Chromatogr B Analyt Technol Biomed Life Sci, 2011 Jul 15;879(22):2179-83.
    PMID: 21689998 DOI: 10.1016/j.jchromb.2011.05.041
    Orthosiphon aristatus is a traditionally used medicinal plant. In order to study the proteome of the plant, we have developed a simple plant protein extraction method by direct extraction of protein using a modified 2D-gel compatible tris-sucrose buffer followed by a double TCA-acetone precipitation. This method omitted the use of toxic phenol which is widely used in the studies of plants proteins. Moreover, it shortens the lengthy extraction procedure of phenol extraction and back-extraction method and therefore reduced the extraction time (by 2h) while increased in protein yields (by 50%). Comparison of the 2D-gel images of the two extracts revealed that >60 extra protein spots were detected in the extract of our current method. The method was applied on the leaves of O. aristatus collected from six geographical areas in Malaysia. The correlation coefficient of each replicate gels from the six areas ranged from 0.70 to 0.90 indicating good reproducibility of the method.
    Matched MeSH terms: Plant Extracts/chemistry*; Plant Proteins/chemistry*; Plant Leaves/chemistry; Orthosiphon/chemistry*
  14. Fulltext The Effect of Cross-linking Efficiency of Drug-Loaded Novel Freeze Gelated Chitosan Templates for Periodontal Tissue Regeneration
    Qasim SSB, Nogueria LP, Fawzy AS, Daood U
    AAPS PharmSciTech, 2020 Jun 16;21(5):173.
    PMID: 32548717 DOI: 10.1208/s12249-020-01708-x
    Innovative strategies for periodontal regeneration have been the focus of research clusters across the globe for decades. In order to overcome the drawbacks of currently available options, investigators have suggested a novel concept of functionally graded membrane (FGM) templates with different structural and morphological gradients. Chitosan (CH) has been used in the past for similar purpose. However, the composite formulation of composite and tetracycline when cross-linked with glutaraldehyde have received little attention. Therefore, the purpose of the study was to investigate the drug loading and release characteristics of novel freeze gelated chitosan templates at different percentages of glutaraldehyde. These were cross-linked with 0.1 and 1% glutaraldehyde and loaded with doxycycline hyclate. The electron micrographs depicted porous morphology of neat templates. After cross-linking, these templates showed compressed ultrastructures. Computerized tomography analysis showed that the templates had 88 to 92% porosity with average pore diameter decreased from 78 to 44.9 μm with increasing concentration. Fourier transform infrared spectroscopy showed alterations in the glycosidic segment of chitosan fingerprint region which after drug loading showed a dominant doxycycline spectral composite profile. Interestingly, swelling profile was not affected by cross-linking either at 0.1 and 1% glutaraldehyde and template showed a swelling ratio of 80%, which gained equilibrium after 15 min. The drug release pattern also showed a 40 μg/mL of release after 24 h. These doxycycline-loaded templates show their tendency to be used in a functionally graded membrane facing the defect site.
    Matched MeSH terms: Biocompatible Materials/chemistry*; Cross-Linking Reagents/chemistry*; Glutaral/chemistry; Chitosan/chemistry*
  15. Natural and synthetic estrogens in leafy vegetable and their risk associated to human health
    Adeel M, Zain M, Fahad S, Rizwan M, Ameen A, Yi H, et al.
    Environ Sci Pollut Res Int, 2018 Dec;25(36):36712-36723.
    PMID: 30377972 DOI: 10.1007/s11356-018-3588-4
    Since the inception of global industrialization, the growth of steroid estrogens becomes a matter of emerging serious concern for the rapid population. Steroidal estrogens are potent endocrine-upsetting chemicals that are excreted naturally by vertebrates (e.g., humans and fish) and can enter natural waters through the discharge of treated and raw sewage. Steroidal estrogens in plants may enter the food web and become a serious threat to human health. We evaluated the uptake and accumulation of ethinylestradiol (EE2) and 17β-estradiol (17β-E2) in lettuce plants (Lactuca sativa) grown under controlled environmental condition over 21 days growth period. An effective analytical method based on ultrasonic liquid extraction (ULE) for solid samples and solid phase extraction (SPE) for liquid samples with gas chromatography-mass spectrometry (GC/MS) has been developed to determine the steroid estrogens in lettuce plants. The extent of uptake and accumulation was observed in a dose-dependent manner and roots were major organs for estrogen deposition. Unlike the 17β-E2, EE2 was less accumulated and translocated from root to leaves. For 17β-E2, the distribution in lettuce was primarily to roots after the second week (13%), whereas in leaves it was (10%) over the entire study period. The distribution of EE2 at 2000 μg L-1 in roots and leaves was very low (3.07% and 0.54%) during the first week and then was highest (12% in roots and 8% in leaves) in last week. Bioaccumulation factor values of 17β-E2 and EE2 in roots were 0.33 and 0.29 at 50 μg L-1 concentration as maximum values were found at 50 μg L-1 rather than 500 and 2000 in all observed plant tissues. Similar trend was noticed in roots than leaves for bioconcentration factor as the highest bioconcentration values were observed at 50 μg L-1 concentration instead of 500 and 2000 μg L-1 spiked concentration. These findings mainly indicate the potential for uptake and bioaccumulation of estrogens in lettuce plants. Overall, the estrogen contents in lettuce were compared to the FAO/WHO recommended toxic level and were found to be higher than the toxic level which is of serious concern to the public health. This analytical procedure may aid in future studies on risks associated with uptake of endocrine-disrupting chemicals in lettuce plants.
    Matched MeSH terms: Sewage/chemistry; Vegetables/chemistry*; Plant Leaves/chemistry; Lettuce/chemistry*
  16. Synthesis and evaluation of chalcone analogues based pyrimidines as angiotensin converting enzyme inhibitors
    Bukhari SN, Butt AM, Amjad MW, Ahmad W, Shah VH, Trivedi AR
    Pak J Biol Sci, 2013 Nov 01;16(21):1368-72.
    PMID: 24511749
    Hypertension is a widespread and frequently progressive ailment that imparts a foremost threat for cardiovascular and renal disorders. Mammoth efforts are needed for the synthesis of innovative antihypertensive agents to combat this lethal disease. Chalcones have shown antihypertensive activity through inhibition of Angiotensin Converting Enzyme (ACE). Hence, a series of chalcone analogues is synthesized and used as precursor for the synthesis of novel series of pyrimidines. Precursor chalcones were prepared by reacting aldehydes and ketones in presence of sodium hydroxide followed by synthesis of corresponding pyrimidines by reaction with urea in presence of potassium hydroxide. Both groups were then evaluated for their effects on ACE. The results depicted that pyrimidines were more active than chalcones with methoxy (C5 and P5) substitution showing best results to inhibit ACE. Given that chalcone analogues and pyrimidines show a potential as the angiotensin converting enzyme inhibitors.
    Matched MeSH terms: Angiotensin-Converting Enzyme Inhibitors/chemistry*; Antihypertensive Agents/chemistry; Chalcone/chemistry; Pyrimidines/chemistry*
  17. Inhibitory effects of edible seaweeds, polyphenolics and alginates on the activities of porcine pancreatic α-amylase
    Zaharudin N, Salmeán AA, Dragsted LO
    Food Chem, 2018 Apr 15;245:1196-1203.
    PMID: 29287342 DOI: 10.1016/j.foodchem.2017.11.027
    Edible seaweeds are valuable because of their organoleptic properties and complex polysaccharide content. A study was conducted to investigate the potential of dried edible seaweed extracts, its potential phenolic compounds and alginates for α-amylase inhibitory effects. The kinetics of inhibition was assessed in comparison with acarbose. The methanol extract of Laminaria digitata and the acetone extract of Undaria pinnatifida showed inhibitory activity against α-amylase, IC50 0.74 ± 0.02 mg/ml and 0.81 ± 0.03 mg/ml, respectively; both showed mixed-type inhibition. Phenolic compound, 2,5-dihydroxybenzoic acid was found to be a potent inhibitor of α-amylase with an IC50 value of 0.046 ± 0.004 mg/ml. Alginates found in brown seaweeds appeared to be potent inhibitors of α-amylase activity with an IC50 of (0.075 ± 0.010-0.103 ± 0.017) mg/ml, also a mixed-type inhibition. Overall, the findings provide information that crude extracts of brown edible seaweeds, phenolic compounds and alginates are potent α-amylase inhibitors, thereby potentially retarding glucose liberation from starches and alleviation of postprandial hyperglycaemia.
    Matched MeSH terms: Enzyme Inhibitors/chemistry; Laminaria/chemistry; Seaweed/chemistry*; Undaria/chemistry
  18. Fulltext Impact of specific functional groups in flavonoids on the modulation of platelet activation
    Ravishankar D, Salamah M, Akimbaev A, Williams HF, Albadawi DAI, Vaiyapuri R, et al.
    Sci Rep, 2018 Jun 22;8(1):9528.
    PMID: 29934595 DOI: 10.1038/s41598-018-27809-z
    Flavonoids exert innumerable beneficial effects on cardiovascular health including the reduction of platelet activation, and thereby, thrombosis. Hence, flavonoids are deemed to be a molecular template for the design of novel therapeutic agents for various diseases including thrombotic conditions. However, the structure-activity relationships of flavonoids with platelets is not fully understood. Therefore, this study aims to advance the current knowledge on structure-activity relationships of flavonoids through a systematic analysis of structurally-related flavones. Here, we investigated a panel of 16 synthetic flavones containing hydroxy or methoxy groups at C-7,8 positions on the A-ring, with a phenyl group or its bioisosteres as the B-ring, along with their thio analogues possessing a sulfur molecule at the 4th carbon position of the C-ring. The antiplatelet efficacies of these compounds were analysed using human isolated platelets upon activation with cross-linked collagen-related peptide by optical aggregometry. The results demonstrate that the hydroxyl groups in flavonoids are important for optimum platelet inhibitory activities. In addition, the 4-C=O and B ring phenyl groups are less critical for the antiplatelet activity of these flavonoids. This structure-activity relationship of flavonoids with the modulation of platelet function may guide the design, optimisation and development of flavonoid scaffolds as antiplatelet agents.
    Matched MeSH terms: Flavonoids/chemistry*; Furans/chemistry; Platelet Aggregation Inhibitors/chemistry*; Pyridines/chemistry
  19. Fulltext Inhibitory Effect of Eco-Friendly Naturally Synthesized Silver Nanoparticles from the Leaf Extract of Medicinal Detarium microcarpum Plant on Pancreatic and Cervical Cancer Cells
    Adebayo IA, Arsad H, Gagman HA, Ismail NZ, Samian MR
    Asian Pac J Cancer Prev, 2020 May 01;21(5):1247-1252.
    PMID: 32458629 DOI: 10.31557/APJCP.2020.21.5.1247
    BACKGROUND: Recently, nanoparticle synthesis by eco-friendly methods has received tremendous attention due to the method advantages and also because of the application of the nanoparticles in cancer research. Therefore, in this study, we synthesized silver nanoparticles from Detarium microcarpum leaf phytochemicals and evaluated its inhibitory effect on pancreatic and cervical cancer cells.

    MATERIALS AND METHODS: Silver nanoparticles (dAgNps) were synthesized by reacting phytochemicals of D. microcarpum leaves with silver nitrate for 12 hours. Cell viability assay was carried out to investigate the cytotoxic effect of dAgNps on HeLa and PANC-1 cells.

    RESULTS: Scanning electron microscopy (SEM) and transmission electron microscopy(TEM) results revealed the average sizes of dAgNps are 81 nm and 84 nm respectively. The x-ray diffraction (XRD) pattern of dAgNps was similar to that of face centered cubic(fcc) structure of silver as reported by joint committee on powder diffraction standards (JCPDS) and fourier-transform infrared spectroscopy (FTIR) analysis showed that some phytochemicals of D. microcarpum such as polyphenols and flavonoids were likely involved in the reduction of Ag+ to form nanoparticles. Finally, cell viability assay revealed dAgNps inhibited PANC-1 and HeLa cell proliferations with IC50 values of 84 and 31.5 µg/ml respectively.

    CONCLUSION: In conclusion, the synthesized nanoparticles from D. microcarpum leaves (dAgNps) have inhibitory effect on pancreatic and cervical cancer cells.

    Matched MeSH terms: Fabaceae/chemistry*; Silver/chemistry*; Plant Leaves/chemistry*; Metal Nanoparticles/chemistry
  20. Fulltext Effect of sintering parameters on physical and mechanical properties of powder injection moulded stainless steel-hydroxyapatite composite
    Ramli MI, Sulong AB, Muhamad N, Muchtar A, Arifin A, Mohd Foudzi F, et al.
    PLoS One, 2018;13(10):e0206247.
    PMID: 30359433 DOI: 10.1371/journal.pone.0206247
    The combination of metallic bio-inert material, stainless-steel 316L (SS316L) and a bio-active material, hydroxyapatite (HA) can produce a composite which has superior properties for orthopaedic applications. The main objective of this study is to investigate the effects of sintering temperature and holding time on the physical and mechanical properties of the sintered part. 50wt.% SS316L and 50wt.% HA were mixed with a binder system of palm stearin (PS) and polyethylene (PE) at 61 vol.% powder loading. Rheological properties show a pseudo-plastic behaviour of the feedstock, where viscosity decreases with increasing shear rate. The feedstock was injection moulded into a tensile bar shape while thermal debinding was carried out at 320°C and 500°C. The brown parts were sintered at 1000, 1100, 1200 and 1300°C, with three different sintering times of 1, 3 and 5 hours in the furnace. It was found that the highest sintered density measured was 95.61% of the theoretical density. In addition, the highest hardness and Young's modulus measured were 150.45 HV and 52.61 GPa respectively, which are higher than those of human bone. The lowest percentage of carbon content was 0.022wt.% given by the sample sintered at 1300°C for 1 hour. Therefore, SS316L/HA composite with good mechanical and physical properties was successfully produced through the PIM process.
    Matched MeSH terms: Powders/chemistry; Stainless Steel/chemistry*; Durapatite/chemistry*; Coated Materials, Biocompatible/chemistry*
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