Publications 2022

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https://hdl.handle.net/20.500.14170/3706

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Now showing 1 - 5 of 325
  • Publication
    Influence of Cellulose Filler Extracted from Napier Grass on Thermal Characterizations, Moisture Content, Tensile Strength, Biodegradation, and Morphological Structure of Bioplastic Films
    ( 2022-01-01)
    Tuan Rohadi T.N.
    ;
    Ridzuan M.J.M.
    ;
    Mohd Shukry Abdul Majid
    ;
    Mamat N.
    ;
    Sulaiman M.H.
    This paper reports on the effects of Napier grass (NG) cellulose used as a filler on the thermal characterizations, moisture content, tensile strength, biodegradation, and morphological structure of bioplastic films. Bioplastic films were obtained from chitosan and gelatin; and from the fiber, bark, and whole of Napier grass (NG). The films were prepared by solution casting with 1, 1.5, 2, and 2.5 wt.% of cellulose content. Alkali and bleaching treatments were performed on the cellulose using 8% sodium hydroxide and 1.7% sodium chlorite. The results reveal that the tensile strength of the bioplastic film with 2 wt.% of fiber filler was the highest and decreased when the cellulose filler loading was 2.5 wt.%. Increasing the cellulose loading accelerated the biodegradation rate of the bioplastic films. The addition of the fiber filler had improved compatibility among the components and the barrier properties of the film that led to a less-porous film.
      3
  • Publication
    N-acyl-homoserine lactone mediated virulence factor(s) of Pseudomonas aeruginosa inhibited by flavonoids and isoflavonoids
    ( 2022-05-01)
    Pachaiappan R.
    ;
    Rajamuthu T.P.
    ;
    Sarkar A.
    ;
    Natrajan P.
    ;
    Krishnan N.
    ;
    Sakthivelu M.
    ;
    Velusamy P.
    ;
    Ramasamy P.
    ;
    Gopinath S.C.B.
    Targeting quorum sensing controlled virulence factor in disease causing Pseudomonas aeruginosa has been an effective approach to cope with antibiotic resistance. Plant derivative compounds for example flavonoids and isoflavonoids have been identified as essential molecules of human diet and are known to possess various pharmacological properties. In this study, two flavonoids (apigenin and acacetin) and three isoflavonoids (genistein, daidzein and biochanin A) were investigated against N-acyl-homoserine lactone (AHL) intermediated virulence factor production in P. aeruginosa. The virulence factors that were focused in the current study are biofilm formation, synthesis of pyoverdin, pyocyanin, rhamnolipid as well as exo-polysaccharide. The RT-qPCR was also performed to analyse the virulence genes expression. Based on the experimental studies, it was observed that the flavone acacetin exhibited the strongest inhibition capacity towards all the bacterial virulence factors. Moreover, a significant down regulation in the expression of virulence genes upon treatment with the compounds was observed, suggesting that these compounds are effective targets for anti-quorum sensing approach.
      1
  • Publication
    Sensitive silica-alumina modified capacitive non-Faradaic glucose sensor for gestational diabetes
    ( 2022-04-01)
    Chen L.
    ;
    Xie W.
    ;
    Luo Y.
    ;
    Ding X.
    ;
    Fu B.
    ;
    Gopinath S.C.B.
    ;
    Xiong Y.
    A highly sensitive silica-alumina (Si-Al)-modified capacitive non-Faradaic glucose biosensor was introduced to monitor gestational diabetes. Glucose oxidase (GOx) was attached to the Si-Al electrode surface as the probe through amine-modification followed by glutaraldehyde premixed GOx as aldehyde-amine chemistry. This Si-Al (∼50 nm) modified electrode surface has increased the current flow upon binding of GOx with glucose. Capacitance values were increased by increasing the glucose concentrations. A mean capacitance value was plotted and the detection limit was found as 0.03 mg/mL with the regression coefficient value, R² = 0.9782 [y = 0.8391x + 1.338] on the linear range between 0.03 and 1 mg/mL. Further, a biofouling experiment with fructose and galactose did not increase the capacitance, indicating the specific glucose detection. This Si-Al–modified capacitance sensor detects a lower level of glucose presence and helps in monitoring gestational diabetes.
      1
  • Publication
    Enhancing erythrocyte–influenza virus specificity by glycan-conjugated gold nanoparticle: Validation of hemagglutination by aptamer and neuraminidases
    ( 2022-04-01)
    Ye M.
    ;
    Lin L.
    ;
    Yang W.
    ;
    Subash Chandra Bose Gopinath
    This study demonstrated the terminated sialo-sugar chains (Neu5Acα2,6Gal and Neu5Acα2,3Gal)-mediated specificity enhancement of influenza virus and chicken red blood cell (RBC) by hemagglutination assay. These glycan chains were immobilized on the gold nanoparticle (GNP) to withhold the higher numbers. With the preliminary optimization, a clear button formation with 0.5% RBC was visualized. On the other hand, intact B/Tokio/53/99 with 750 nM hemagglutinin (HA) displayed a nice hemagglutination. The interference on the specificity of RBC and influenza virus was observed by anti-influenza aptamer at the concentration 31 nM; however, there is no hemagglutination prevention was noticed in the presence of complementary aptamer sequences. Spiking GNP-conjugated Neu5Acα2,6Gal or Neu5Acα2,3Gal or a mixture of these two to the reaction promoted the hemagglutination to 63-folds higher with 12 nM virus, whereas under the same condition the heat-inactivated viruses were lost the hemagglutination. Neuraminidases from Clostridium perfringens and Arthrobacter ureafaciens at 0.0025 neuraminidase units are able to abolish the hemagglutination. Other enzymes, Glycopeptidase F (Elizabethkingia meningoseptica) and Endoglycosidase H (Streptomyces plicatus) did not show the changes with agglutination. Obviously, sialyl-Gal-terminated glycan-conjugated GNP amendment has enhanced the specificity of erythrocyte–influenza virus and able to be controlled by aptamer or neuraminidases.
      3
  • Publication
    Surface engineered iron oxide nanoparticles as efficient materials for antibiofilm application
    ( 2022-04-01)
    Velusamy P.
    ;
    Su C.H.
    ;
    Kannan K.
    ;
    Kumar G.V.
    ;
    Anbu P.
    ;
    Subash Chandra Bose Gopinath
    Overuse of antibiotics has led to the development of multidrug-resistant strains. Antibiotic resistance is a major drawback in the biomedical field since medical implants are prone to infection by biofilms of antibiotic resistant strains of bacteria. With increasing prevalence of antibiotic-resistant pathogenic bacteria, the search for alternative method is utmost importance. In this regard, magnetic nanoparticles are commonly used as a substitute for antibiotics that can circumvent the problem of biofilms growth on the surface of biomedical implants. Iron oxide nanoparticles (IONPs) have unique magnetic properties that can be exploited in various ways in the biomedical applications. IONPs are engineered employing different methods to induce surface functionalization that include the use of polyethyleneimine and oleic acid. IONPs have a mechanical effect on biofilms in presence of an external magnet. In this review, a detailed description of surface-engineered magnetic nanoparticles as ideal antibacterial agents is provided, accompanied by various methods of literature review.
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