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  1. Fulltext Simultaneous detection of methicillin-resistant Staphylococcus aureus, Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa by multiplex PCR
    Thong KL, Lai MY, Teh C SJ, Chua KH
    Trop Biomed, 2011 Apr;28(1):21-31.
    PMID: 21602765 MyJurnal
    A PCR-based assay that can simultaneously detect and differentiate five different types of nosocomial bacterial pathogens was developed. Six pairs of selected primers targeting femA (132 bp) and mecA (310 bp) of methicillin-resistant Staphylococcus aureus, gltA (722 bp) of Acinetobacter baumannii, phoA (903 bp) of Escherichia coli, mdh (364 bp) of Klebsiella pneumoniae and oprL (504 bp) of Pseudomonas aeruginosa were used in this study. The conditions were optimized for the multiplex PCR to ensure specific amplification of the selected targets. Sensitivity and specificity tests were also carried out using a blind test approach on 50 bacterial cultures and resulted in 100% for both positive and negative predictive values.
    Matched MeSH terms: Escherichia coli/isolation & purification; Klebsiella pneumoniae/isolation & purification; Pseudomonas aeruginosa/isolation & purification; Acinetobacter baumannii/isolation & purification; Methicillin-Resistant Staphylococcus aureus/isolation & purification
  2. Study of Antioxidant, Antiproliferative and DNA Damage Protecting Activities of Cinnamomum cassia Extracts Obtained by Sequential Extraction
    Rad SK, Movafagh A
    Recent Pat Food Nutr Agric, 2021;12(1):45-57.
    PMID: 32807070 DOI: 10.2174/2212798411666200817120307
    BACKGROUND: Cinnamomum cassia (C. cassia) is an evergreen tree in China and Southern and Eastern Asia. In traditional medicine, cinnamon is widely used due to its many bioactivity effects.

    OBJECTIVE: The present novel study aims to evaluate and make a comparison of antioxidant and antiproliferative activities of different extractions of C. cassia bark using seven solvents having different polarities. Solvents polarity gradients start with the solvent of lower polarity, n-hexane, and end with water as the highest polar solvent. Among the extracts, acetone extract contains the highest phenolic and flavonoid contents; therefore, it is assessed for the ability to protect DNA from damage.

    METHODS: The extracts are evaluated for total phenolic, flavonoid contents and antioxidant activities, using FRAP, DPPH, superoxide, and hydroxyl and nitric oxide radicals scavenging assays. DNA damage protecting activity of the acetone extract is studied with the comet assay. Each of the extracts is studied for its antiproliferative effect against, MCF-7, MDA-MB-231(breast cancer), and HT29 (colon cancer), using MTT assay.

    RESULTS: The acetone extract exhibited the highest FRAP value, phenolic and flavonoids contents when compared to the other extracts and could protect 45% mouse fibroblast cell line (3T3-L1) from DNA damage at 30 μg/ml. The lowest IC50 value in DPPH, superoxide, and hydroxyl radicals scavenging was noticed in the ethyl acetate extract. IC50 value obtained for the hexane extract was the lowest compared to the other extracts in scavenging nitric oxide radicals. The hexane extract showed the highest antiproliferative effect against cancer cells followed by the chloroform extract. The ethyl acetate extract inhibited the proliferation of only MCF-7 by IC50 of 100 μg/ml, while the other extracts exhibited no IC50 in all the cancer cells.

    CONCLUSION: C. cassia showed promising antioxidant and anticancer activities with significant DNA damage protecting effect.

    Matched MeSH terms: Antineoplastic Agents, Phytogenic/isolation & purification; Antioxidants/isolation & purification; Flavonoids/isolation & purification; Phenols/isolation & purification; Plant Extracts/isolation & purification
  3. High angiotensin-I converting enzyme (ACE) inhibitory activity of Alcalase-digested green soybean (Glycine max) hydrolysates
    Hanafi MA, Hashim SN, Chay SY, Ebrahimpour A, Zarei M, Muhammad K, et al.
    Food Res Int, 2018 04;106:589-597.
    PMID: 29579964 DOI: 10.1016/j.foodres.2018.01.030
    As a protein-rich, underutilized crop, green soybean could be exploited to produce hydrolysates containing angiotensin-I converting enzyme (ACE) inhibitory peptides. Defatted green soybean was hydrolyzed using four different food-grade proteases (Alcalase, Papain, Flavourzyme and Bromelain) and their ACE inhibitory activities were evaluated. The Alcalase-generated green soybean hydrolysate showed the highest ACE inhibitory activity (IC50: 0.14 mg/mL at 6 h hydrolysis time) followed by Papain (IC50: 0.20 mg/mL at 5 h hydrolysis time), Bromelain (IC50: 0.36 mg/mL at 6 h hydrolysis time) and Flavourzyme (IC50: 1.14 mg/mL at 6 h hydrolysis time) hydrolysates. The Alcalase-generated hydrolysate was profiled based on its hydrophobicity and isoelectric point using reversed phase high performance liquid chromatography (RP-HPLC) and isoelectric point focusing (IEF) fractionators. The Alcalase-generated green soybean hydrolysate comprising of peptides EAQRLLF, PSLRSYLAE, PDRSIHGRQLAE, FITAFR and RGQVLS, revealed the highest ACE inhibitory activity of 94.19%, 99.31%, 92.92%, 101.51% and 90.40%, respectively, while their IC50 values were 878 μM, 532 μM, 1552 μM, 1342 μM and 993 μM, respectively. It can be concluded that Alcalase-digested green soybean hydrolysates could be exploited as a source of peptides to be incorporated into functional foods with antihypertensive activity.
    Matched MeSH terms: Angiotensin-Converting Enzyme Inhibitors/isolation & purification; Antihypertensive Agents/isolation & purification; Peptides/isolation & purification; Protein Hydrolysates/isolation & purification; Soybean Proteins/isolation & purification
  4. Anti-inflammatory effects of mulberry (Morus alba L.) root bark and its active compounds
    Wu YX, Kim YJ, Kwon TH, Tan CP, Son KH, Kim T
    Nat Prod Res, 2020 Jun;34(12):1786-1790.
    PMID: 30470128 DOI: 10.1080/14786419.2018.1527832
    Mulberry (Morus alba L.) root bark (MRB) was extracted using methanol and the extracts were subjected to tests of anti-inflammatory effects. The ethyl acetate fraction demonstrated the best anti-inflammatory effects. Purified compounds, sanggenon B, albanol B and sanggenon D, showed inhibitory effects on NO production in LPS-stimulated RAW264.7 cells and albanol B demonstrated the best anti-inflammatory effects. Regarding the underlying molecular mechanisms, further investigations showed that treatments with Albanol B reduced production of pro-inflammatory cytokines and decreased expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). These results would contribute to development of novel anti-inflammatory drugs from MRB.
    Matched MeSH terms: Anti-Inflammatory Agents/isolation & purification*; Benzofurans/isolation & purification; Chromones/isolation & purification; Flavonoids/isolation & purification; Cyclooxygenase 2 Inhibitors/isolation & purification
  5. Fulltext Streptomyces sp. MUM273b: A mangrove-derived potential source for antioxidant and UVB radiation protectants
    Tan LT, Mahendra CK, Yow YY, Chan KG, Khan TM, Lee LH, et al.
    Microbiologyopen, 2019 10;8(10):e859.
    PMID: 31199601 DOI: 10.1002/mbo3.859
    Microbial natural products serve as a good source for antioxidants. The mangrove-derived Streptomyces bacteria have been evidenced to produce antioxidative compounds. This study reports the isolation of Streptomyces sp. MUM273b from mangrove soil that may serve as a promising source of antioxidants and UV-protective agents. Identification and characterization methods determine that strain MUM273b belongs to the genus Streptomyces. The MUM273b extract exhibits antioxidant activities, including DPPH, ABTS, and superoxide radical scavenging activities and also metal-chelating activity. The MUM273b extract was also shown to inhibit the production of malondialdehyde in metal-induced lipid peroxidation. Strong correlation between the antioxidant activities and the total phenolic content of MUM273b extract was shown. In addition, MUM273b extract exhibited cytoprotective effect on the UVB-induced cell death in HaCaT keratinocytes. Gas chromatography-mass spectrometry analysis detected phenolics, pyrrole, pyrazine, ester, and cyclic dipeptides in MUM273b extract. In summary, Streptomyces MUM273b extract portrays an exciting avenue for future antioxidative drugs and cosmeceuticals development.
    Matched MeSH terms: Antioxidants/isolation & purification*; Biological Products/isolation & purification*; Chelating Agents/isolation & purification; Radiation-Protective Agents/isolation & purification*; Streptomyces/isolation & purification
  6. Antiplasmodial and antioxidant isoquinoline alkaloids from Dehaasia longipedicellata
    Zahari A, Cheah FK, Mohamad J, Sulaiman SN, Litaudon M, Leong KH, et al.
    Planta Med, 2014 May;80(7):599-603.
    PMID: 24723007 DOI: 10.1055/s-0034-1368349
    The crude extract of the bark of Dehaasia longipedicellata exhibited antiplasmodial activity against the growth of Plasmodium falciparum K1 isolate (resistant strain). Phytochemical studies of the extract led to the isolation of six alkaloids: two morphinandienones, (+)-sebiferine (1) and (-)-milonine (2); two aporphines, (-)-boldine (3) and (-)-norboldine (4); one benzlyisoquinoline, (-)-reticuline (5); and one bisbenzylisoquinoline, (-)-O-O-dimethylgrisabine (6). Their structures were determined on the basis of 1D and 2D NMR, IR, UV, and LCMS spectroscopic techniques and upon comparison with literature values. Antiplasmodial activity was determined for all of the isolated compounds. They showed potent to moderate activity with IC50 values ranging from 0.031 to 30.40 µM. (-)-O-O-dimethylgrisabine (6) and (-)-milonine (2) were the two most potent compounds, with IC50 values of 0.031 and 0.097 µM, respectively, that were comparable to the standard, chloroquine (0.090 µM). The compounds were also assessed for their antioxidant activities with di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (IC50 = 18.40-107.31 µg/mL), reducing power (27.40-87.40 %), and metal chelating (IC50 = 64.30 to 257.22 µg/mL) having good to low activity. (-)-O-O-dimethylgrisabine (6) exhibited a potent antioxidant activity of 44.3 % reducing power, while di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium and metal chelating activities had IC50 values of 18.38 and 64.30 µg/mL, respectively. Thus it may be considered as a good reductant with the ability to chelate metal and prevent pro-oxidant activity. In addition to the antiplasmodial and antioxidant activities, the isolated compounds were also tested for their cytotoxicity against a few cancer and normal cell lines. (-)-Norboldine (4) exhibited potent cytotoxicity towards pancreatic cancer cell line BxPC-3 with an IC50 value of 27.060 ± 1.037 µM, and all alkaloids showed no toxicity towards the normal pancreatic cell line (hTERT-HPNE).
    Matched MeSH terms: Alkaloids/isolation & purification; Antimalarials/isolation & purification; Antioxidants/isolation & purification; Isoquinolines/isolation & purification; Plant Extracts/isolation & purification
  7. Application of seaweeds to develop new food products with enhanced shelf-life, quality and health-related beneficial properties
    Roohinejad S, Koubaa M, Barba FJ, Saljoughian S, Amid M, Greiner R
    Food Res Int, 2017 09;99(Pt 3):1066-1083.
    PMID: 28865618 DOI: 10.1016/j.foodres.2016.08.016
    Edible seaweeds are a good source of antioxidants, dietary fibers, essential amino acids, vitamins, phytochemicals, polyunsaturated fatty acids, and minerals. Many studies have evaluated the gelling, thickening and therapeutic properties of seaweeds when they are used individually. This review gives an overview on the nutritional, textural, sensorial, and health-related properties of food products enriched with seaweeds and seaweed extracts. The effect of seaweed incorporation on properties of meat, fish, bakery, and other food products were highlighted in depth. Moreover, the positive effects of foods enriched with seaweeds and seaweed extracts on different lifestyle diseases such as obesity, dyslipidemia, hypertension, and diabetes were also discussed. The results of the studies demonstrated that the addition of seaweeds, in powder or extract form, can improve the nutritional and textural properties of food products. Additionally, low-fat products with less calories and less saturated fatty acids can be prepared using seaweeds. Moreover, the addition of seaweeds also affected the health properties of food products. The results of these studies demonstrated that the health value, shelf-life and overall quality of foods can be improved through the addition of either seaweeds or seaweed extracts.
    Matched MeSH terms: Anti-Infective Agents/isolation & purification; Antioxidants/isolation & purification; Colloids/isolation & purification; Food Preservatives/isolation & purification; Plant Preparations/isolation & purification
  8. A new coumarin from stem bark of Calophyllum wallichianum
    Tee KH, Ee GCL, Ismail IS, Karunakaran T, Teh SS, Jong VYM, et al.
    Nat Prod Res, 2018 Nov;32(21):2565-2570.
    PMID: 29355031 DOI: 10.1080/14786419.2018.1428588
    A phytochemical study carried out on the plant, Calophyllum wallichianum has led to the isolation of a new coumarin, wallimarin T (1) and a known coumarin, calanolide E (2) along with two common triterpenes, friedelin (3) and stigmasterol (4). The structures of these compounds were elucidated with the aid of spectroscopic analyses such as FT-IR, GC-MS, and NMR. MIC assay against the Bacillus bacteria were conducted on the extracts and this gave MIC values ranging from 0.313 to 1.25 mg/mL. Compound 2 was weakly inhibitory towards the Bacilli strains with MIC values ranging from 0.25-0.50 mg/mL. Wallimarin T (1) was not active towards all four bacteria. Overall, the extracts exhibited weak bactericidal properties whereas compound 2 was not bactericidal on the tested bacteria. The hexane and chloroform extracts of the plant were found to be inhibitors to the growth of Bacillus megaterium, Bacillus cereus, Bacillus pumilus and Bacillus subtilis.
    Matched MeSH terms: Anti-Bacterial Agents/isolation & purification; Coumarins/isolation & purification; Stigmasterol/isolation & purification; Triterpenes/isolation & purification; Phytochemicals/isolation & purification
  9. α-glucosidase inhibitors isolated from Mimosa pudica L
    Tasnuva ST, Qamar UA, Ghafoor K, Sahena F, Jahurul MHA, Rukshana AH, et al.
    Nat Prod Res, 2019 May;33(10):1495-1499.
    PMID: 29281898 DOI: 10.1080/14786419.2017.1419224
    The aim of the study was to isolate digestive enzymes inhibitors from Mimosa pudica through a bioassay-guided fractionation approach. Repeated silica gel and sephadex LH 20 column chromatographies of bioactive fractions afforded stigmasterol, quercetin and avicularin as digestive enzymes inhibitors whose IC50 values as compared to acarbose (351.02 ± 1.46 μg mL-1) were found to be as 91.08 ± 1.54, 75.16 ± 0.92 and 481.7 ± 0.703 μg mL-1, respectively. In conclusion, M. pudica could be a good and safe source of digestive enzymes inhibitors for the management of diabetes in future.
    Matched MeSH terms: Flavonoids/isolation & purification; Hypoglycemic Agents/isolation & purification; Quercetin/isolation & purification; Stigmasterol/isolation & purification; Glycoside Hydrolase Inhibitors/isolation & purification*
  10. Fulltext Inhibitory effects of phylligenin and quebrachitol isolated from Mitrephora vulpina on platelet activating factor receptor binding and platelet aggregation
    Moharam BA, Jantan I, Jalil J, Shaari K
    Molecules, 2010 Nov 03;15(11):7840-8.
    PMID: 21060292 DOI: 10.3390/molecules15117840
    Phylligenine, together with quebrachitol, stigmasterol and two aporphine alkaloids--oxoputerine and liriodenine--were isolated from the twigs of Mitrephora vulpina C.E.C. Fisch. They were evaluated for their ability to inhibit platelet activating factor (PAF) receptor binding to rabbit platelets using 3H-PAF as a ligand and their antiplatelet aggregation effect in human whole blood induced by arachidonic acid (AA), collagen and adenosine diphosphate (ADP). Of all the compounds tested, phylligenin and quebrachitol exhibited potent and concentration-dependent inhibitory effects on PAF receptor binding, with IC(50) values of 13.1 and 42.2 µM, respectively. The IC(50) value of phylligenin was comparable to that of cedrol (10.2 µM), a potent PAF antagonist. Phylligenin also showed strong dose-dependent inhibitory activity on platelet aggregation induced by AA and ADP.
    Matched MeSH terms: Alkaloids/isolation & purification; Aporphines/isolation & purification; Inositol/isolation & purification; Stigmasterol/isolation & purification; Lignans/isolation & purification
  11. Fulltext A Review of the Biomedical Applications of Zerumbone and the Techniques for Its Extraction from Ginger Rhizomes
    Kalantari K, Moniri M, Boroumand Moghaddam A, Abdul Rahim R, Bin Ariff A, Izadiyan Z, et al.
    Molecules, 2017 Sep 30;22(10).
    PMID: 28974019 DOI: 10.3390/molecules22101645
    Zerumbone (ZER) is a phytochemical isolated from the subtropical Zingiberaceae family and as a natural compound it has different biomedical properties such as antioxidant, anti-inflammatory anti-proliferative activity. ZER also has effects on angiogenesis and acts as an antitumor drug in the treatment of cancer, showing selective toxicity toward various cancer cell lines. Several techniques also have been established for extraction of ZER from the rhizomes of ginger. This review paper is an overview of recent research about different extraction methods and their efficiencies, in vivo and vitro investigations of ZER and also its prominent chemopreventive properties and treatment mechanisms. Most of the studies mentioned in this review paper may be useful use as a knowledge summary to explain ZER extraction and anticancer activities, which will show a way for the development of strategies in the treatment of malignancies using ZER.
    Matched MeSH terms: Anti-Inflammatory Agents/isolation & purification; Antineoplastic Agents/isolation & purification; Antioxidants/isolation & purification; Plant Extracts/isolation & purification; Sesquiterpenes/isolation & purification
  12. Fulltext Detection of novel respiratory viruses from influenza-like illness in the Philippines
    Furuse Y, Suzuki A, Kishi M, Galang HO, Lupisan SP, Olveda RM, et al.
    J Med Virol, 2010 May;82(6):1071-4.
    PMID: 20419824 DOI: 10.1002/jmv.21763
    Several novel viruses have been recently identified in respiratory samples. However, the epidemiology of these viruses in tropical countries remains unclear. The aim of the present study was to provide an overview of the epidemiology of novel respiratory viruses, including human metapneumovirus, human bocavirus, new subtypes of human coronavirus (NL63 and HKU1), KI virus, WU virus, and Melaka virus in the Philippines, a tropical country. Nasopharyngeal aspirates from 465 patients with influenza-like illness were collected in 2006 and 2007. Reverse transcription polymerase chain reaction (RT-PCR) and PCR were performed to detect viruses from culture-negative specimens. Human metapneumovirus, human bocavirus, human coronavirus HKU1, KI virus, and WU virus were detected for the first time in the Philippines; Melaka virus was not found.
    Matched MeSH terms: Polyomavirus/isolation & purification; Reoviridae/isolation & purification; Coronavirus/isolation & purification; Metapneumovirus/isolation & purification; Human bocavirus/isolation & purification
  13. Fulltext Detection of Helminth Eggs and Identification of Hookworm Species in Stray Cats, Dogs and Soil from Klang Valley, Malaysia
    Tun S, Ithoi I, Mahmud R, Samsudin NI, Kek Heng C, Ling LY
    PLoS One, 2015;10(12):e0142231.
    PMID: 26671680 DOI: 10.1371/journal.pone.0142231
    The present study was conducted to determine the prevalence of helminth eggs excreted in the faeces of stray cats, dogs and in soil samples. A total of 505 fresh samples of faeces (from 227 dogs and 152 cats) and soil were collected. The egg stage was detected via microscopy after the application of formalin-ether concentration technique. Genomic DNA was extracted from the samples containing hookworm eggs and used for further identification to the species level using real-time polymerase chain reaction coupled with high resolution melting analysis. Microscopic observation showed that the overall prevalence of helminth eggs among stray cats and dogs was 75.7% (95% CI = 71.2%-79.9%), in which 87.7% of dogs and 57.9% of cats were infected with at least one parasite genus. Five genera of heliminth eggs were detected in the faecal samples, including hookworms (46.4%), Toxocara (11.1%), Trichuris (8.4%), Spirometra (7.4%) and Ascaris (2.4%). The prevalence of helminth infections among stray dogs was significantly higher than that among stray cats (p < 0.001). Only three genera of helminths were detected in soil samples with the prevalence of 23% (95% CI = 15.1%-31%), consisting of hookworms (16.6%), Ascaris (4%) and Toxocara (2.4%). The molecular identification of hookworm species revealed that Ancylostoma ceylanicum was dominant in both faecal and soil samples. The dog hookworm, Ancylostoma caninum, was also detected among cats, which is the first such occurrence reported in Malaysia till date. This finding indicated that there was a cross-infection of A. caninum between stray cats and dogs because of their coexistent within human communities. Taken together, these data suggest the potential role of stray cats and dogs as being the main sources of environmental contamination as well as for human infections.
    Matched MeSH terms: Ancylostomatoidea/isolation & purification*
  14. Unantimycin A, a new neoantimycin analog isolated from a microbial metabolite fraction library
    Lim CL, Nogawa T, Okano A, Futamura Y, Kawatani M, Takahashi S, et al.
    J Antibiot (Tokyo), 2016 06;69(6):456-8.
    PMID: 26648115 DOI: 10.1038/ja.2015.124
    Matched MeSH terms: Macrocyclic Compounds/isolation & purification*
  15. Fulltext A novel aqueous micellar two-phase system composed of surfactant and sorbitol for purification of pectinase enzyme from Psidium guajava and recycling phase components
    Amid M, Murshid FS, Manap MY, Hussin M
    Biomed Res Int, 2015;2015:815413.
    PMID: 25756051 DOI: 10.1155/2015/815413
    A novel aqueous two-phase system composed of a surfactant and sorbitol was employed for the first time to purify pectinase from Psidium guajava. The influences of different parameters, including the type and concentration of the surfactant and the concentration and composition of the surfactant/sorbitol ratio, on the partitioning behavior and recovery of pectinase were investigated. Moreover, the effects of system pH and the crude load on purification fold and the yield of purified pectinase were studied. The experimental results indicated that the pectinase was partitioned into surfactant-rich top phase, and the impurities were partitioned into the sorbitol-rich bottom phase with the novel method involving an ATPS composed of 26% (w/w) Triton X-100 and 23% (w/w) sorbitol at 54.2% of the TLL crude load of 20% (w/w) at pH 6.0. The enzyme was successfully recovered by this method with a high purification factor of 15.2 and a yield of 98.3%, whereas the phase components were also recovered and recycled at rates above 96%. This study demonstrated that this novel ATPS method can be used as an efficient and economical alternative to the traditional ATPS for the purification and recovery of the valuable enzyme.
    Matched MeSH terms: Polygalacturonase/isolation & purification*
  16. Fulltext Apropos: Plasmodium knowlesi malaria an emerging public health problem in Hulu Selangor, Selangor, Malaysia (2009-2013): epidemiologic and entomologic analysis
    Waugh S
    Parasit Vectors, 2015;8:79.
    PMID: 25651916 DOI: 10.1186/s13071-015-0694-8
    The use of detailed methodologies and legitimate settings justifications in spatial analysis is imperative to locating areas of significance. Studies missing this action may enact interventions in improper areas.
    Matched MeSH terms: Plasmodium knowlesi/isolation & purification*
  17. Opsoclonus-myoclonus-ataxia syndrome associated with dengue virus infection
    Tan AH, Linn K, Sam IC, Tan CT, Lim SY
    Parkinsonism Relat Disord, 2015 Feb;21(2):160-1.
    PMID: 25443556 DOI: 10.1016/j.parkreldis.2014.11.009
    Matched MeSH terms: Dengue Virus/isolation & purification*
  18. Characterization of bovine serum albumin partitioning behaviors in polymer-salt aqueous two-phase systems
    Chow YH, Yap YJ, Tan CP, Anuar MS, Tejo BA, Show PL, et al.
    J Biosci Bioeng, 2015 Jul;120(1):85-90.
    PMID: 25553974 DOI: 10.1016/j.jbiosc.2014.11.021
    In this paper, a linear relationship is proposed relating the natural logarithm of partition coefficient, ln K for protein partitioning in poly (ethylene glycol) (PEG)-phosphate aqueous two-phase system (ATPS) to the square of tie-line length (TLL(2)). This relationship provides good fits (r(2) > 0.98) to the partition of bovine serum albumin (BSA) in PEG (1450 g/mol, 2000 g/mol, 3350 g/mol, and 4000 g/mol)-phosphate ATPS with TLL of 25.0-50.0% (w/w) at pH 7.0. Results also showed that the plot of ln K against pH for BSA partitioning in the ATPS containing 33.0% (w/w) PEG1450 and 8.0% (w/w) phosphate with varied working pH between 6.0 and 9.0 exhibited a linear relationship which is in good agreement (r(2) = 0.94) with the proposed relationship, ln K = α' pH + β'. These results suggested that both the relationships proposed could be applied to correlate and elucidate the partition behavior of biomolecules in the polymer-salt ATPS. The influence of other system parameters on the partition behavior of BSA was also investigated. An optimum BSA yield of 90.80% in the top phase and K of 2.40 was achieved in an ATPS constituted with 33.0% (w/w) PEG 1450 and 8.0% (w/w) phosphate in the presence of 8.5% (w/w) sodium chloride (NaCl) at pH 9.0 for 0.3% (w/w) BSA load.
    Matched MeSH terms: Serum Albumin, Bovine/isolation & purification
  19. Highly sensitive silicon nanowire biosensor with novel liquid gate control for detection of specific single-stranded DNA molecules
    Adam T, Hashim U
    Biosens Bioelectron, 2015 May 15;67:656-61.
    PMID: 25453738 DOI: 10.1016/j.bios.2014.10.005
    The study demonstrates the development of a liquid-based gate-control silicon nanowire biosensor for detection of specific single-stranded DNA (ssDNA) molecules. The sensor was fabricated using conventional photolithography coupled with an inductively coupled plasma dry etching process. Prior to the application of DNA to the device, its linear response to pH was confirmed by serial dilution from pH 2 to pH 14. Then, the sensor surface was silanized and directly aminated with (3-aminopropyl) triethoxysilane to create a molecular binding chemistry for biofunctionalization. The resulting Si‒O‒Si‒ components were functionalized with receptor ssDNA, which interacted with the targeted ssDNA to create a field across the silicon nanowire and increase the current. The sensor shows selectivity for the target ssDNA in a linear range from target ssDNA concentrations of 100 pM to 25 nM. With its excellent detection capabilities, this sensor platform is promising for detection of specific biomarkers and other targeted proteins.
    Matched MeSH terms: DNA, Single-Stranded/isolation & purification*
  20. Biosensing enhancement of dengue virus using microballoon mixers on centrifugal microfluidic platforms
    Aeinehvand MM, Ibrahim F, Harun SW, Djordjevic I, Hosseini S, Rothan HA, et al.
    Biosens Bioelectron, 2015 May 15;67:424-30.
    PMID: 25220800 DOI: 10.1016/j.bios.2014.08.076
    Dengue is the current leading cause of death among children in several Latin American and Asian countries. Due to poverty in areas where the disease is prevalent and the high cost of conventional diagnostic systems, low cost devices are needed to reduce the burden caused by dengue infection. Centrifugal microfluidic platforms are an alternative solution to reduce costs and increase the availability of a rapid diagnostic system. The rate of chemical reactions in such devices often depends on the efficiency of the mixing techniques employed in their microfluidic networks. This paper introduces a micromixer that operates by the expansion and contraction of a microballoon to produce a consistent periodical 3D reciprocating flow. We established that microballoons reduced mixing time of 12 μl liquids from 170 min, for diffusional mixing, to less than 23 s. We have also tested the effect of the microballoon mixers on the detection of the dengue virus. The results indicate that employing a microballoon mixer enhances the detection sensitivity of the dengue virus by nearly one order of magnitude compared to the conventional ELISA method.
    Matched MeSH terms: Dengue Virus/isolation & purification*
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