Displaying publications 81 - 100 of 851 in total

Abstract:
Sort:
  1. Biomineralization, mechanical, antibacterial and biological investigation of larnite and rankinite bioceramics
    Venkatraman SK, Choudhary R, Krishnamurithy G, Raghavendran HRB, Murali MR, Kamarul T, et al.
    Mater Sci Eng C Mater Biol Appl, 2021 Jan;118:111466.
    PMID: 33255048 DOI: 10.1016/j.msec.2020.111466
    This work is aimed to develop a biocompatible, bactericidal and mechanically stable biomaterial to overcome the challenges associated with calcium phosphate bioceramics. The influence of chemical composition on synthesis temperature, bioactivity, antibacterial activity and mechanical stability of least explored calcium silicate bioceramics was studied. The current study also investigates the biomedical applications of rankinite (Ca3Si2O7) for the first time. Sol-gel combustion method was employed for their preparation using citric acid as a fuel. Differential thermal analysis indicated that the crystallization of larnite and rankinite occurred at 795 °C and 1000 °C respectively. The transformation of secondary phases into the desired product was confirmed by XRD and FT-IR. TEM micrographs showed the particle size of larnite in the range of 100-200 nm. The surface of the samples was entirely covered by the dominant apatite phase within one week of immersion. Moreover, the compressive strength of larnite and rankinite was found to be 143 MPa and 233 MPa even after 28 days of soaking in SBF. Both samples prevented the growth of clinical pathogens at a concentration of 2 mg/mL. Larnite and rankinite supported the adhesion, proliferation and osteogenic differentiation of hBMSCs. The variation in chemical composition was found to influence the properties of larnite and rankinite. The results observed in this work signify that these materials not only exhibit faster biomineralization ability, excellent cytocompatibility but also enhanced mechanical stability and antibacterial properties.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology
  2. Enterobacteriaceae resistant to third-generation cephalosporins and quinolones in fresh culinary herbs imported from Southeast Asia
    Veldman K, Kant A, Dierikx C, van Essen-Zandbergen A, Wit B, Mevius D
    Int J Food Microbiol, 2014 May 2;177:72-7.
    PMID: 24607424 DOI: 10.1016/j.ijfoodmicro.2014.02.014
    Since multidrug resistant bacteria are frequently reported from Southeast Asia, our study focused on the occurrence of ESBL-producing Enterobacteriaceae in fresh imported herbs from Thailand, Vietnam and Malaysia. Samples were collected from fresh culinary herbs imported from Southeast Asia in which ESBL-suspected isolates were obtained by selective culturing. Analysis included identification by MALDI-TOF mass spectrometry, susceptibility testing, XbaI-PFGE, microarray, PCR and sequencing of specific ESBL genes, PCR based replicon typing (PBRT) of plasmids and Southern blot hybridization. In addition, the quinolone resistance genotype was characterized by screening for plasmid mediated quinolone resistance (PMQR) genes and mutations in the quinolone resistance determining region (QRDR) of gyrA and parC. The study encompassed fifty samples of ten batches of culinary herbs (5 samples per batch) comprising nine different herb variants. The herbs originated from Thailand (Water morning glory, Acacia and Betel leaf), Vietnam (Parsley, Asian pennywort, Houttuynia leaf and Mint) and Malaysia (Holy basil and Parsley). By selective culturing 21 cefotaxime resistant Enterobacteriaceae were retrieved. Array analysis revealed 18 isolates with ESBL genes and one isolate with solely non-ESBL beta-lactamase genes. Mutations in the ampC promoter region were determined in two isolates with PCR and sequencing. The isolates were identified as Klebsiella pneumoniae (n=9), Escherichia coli (n=6), Enterobacter cloacae complex (n=5) and Enterobacter spp. (n=1). All isolates tested were multidrug resistant. Variants of CTX-M enzymes were predominantly found followed by SHV enzymes. PMQR genes (including aac(6')-1b-cr, qnrB and qnrS) were also frequently detected. In almost all cases ESBL and quinolone resistance genes were located on the same plasmid. Imported fresh culinary herbs from Southeast Asia are a potential source for contamination of food with multidrug resistant bacteria. Because these herbs are consumed without appropriate heating, transfer to human bacteria cannot be excluded.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology
  3. Bacterial adherence and biofilm formation on medical implants: a review
    Veerachamy S, Yarlagadda T, Manivasagam G, Yarlagadda PK
    Proc Inst Mech Eng H, 2014 Oct;228(10):1083-99.
    PMID: 25406229 DOI: 10.1177/0954411914556137
    Biofilms are a complex group of microbial cells that adhere to the exopolysaccharide matrix present on the surface of medical devices. Biofilm-associated infections in the medical devices pose a serious problem to the public health and adversely affect the function of the device. Medical implants used in oral and orthopedic surgery are fabricated using alloys such as stainless steel and titanium. The biological behavior, such as osseointegration and its antibacterial activity, essentially depends on both the chemical composition and the morphology of the surface of the device. Surface treatment of medical implants by various physical and chemical techniques are attempted in order to improve their surface properties so as to facilitate bio-integration and prevent bacterial adhesion. The potential source of infection of the surrounding tissue and antimicrobial strategies are from bacteria adherent to or in a biofilm on the implant which should prevent both biofilm formation and tissue colonization. This article provides an overview of bacterial biofilm formation and methods adopted for the inhibition of bacterial adhesion on medical implants.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology
  4. Antimicrobial and bactericidal impacts of Bacillus amyloliquefaciens CECT 5940 on fecal shedding of pathogenic bacteria in dairy calves and adult dogs
    Vazquez-Mendoza P, Elghandour MMM, Alaba PA, Sánchez-Aparicio P, Alonso-Fresán MU, Barbabosa-Pliego A, et al.
    Microb Pathog, 2018 Jan;114:458-463.
    PMID: 29180295 DOI: 10.1016/j.micpath.2017.11.040
    Two experiments were carried out to evaluate the bactericidal impacts of Bacillus amyloliquefaciens CECT 5940 on the shedding of faecal pathogenic bacteria in dairy calves (Experiment 1) and in adults dogs (experiment 2). In the calves experiment, a completely randomized design was used to investigate the faecal bacteria profile of Holstein dairy calves fed with either pasteurized waste milk (PWM; n = 9) or a formulated non-medicated milk replacer (NMR; n = 9) for 60 d. The NMR containing sodium-butyrate and the active probiotic B. amyloliquefaciens CECT 5940. In the dogs experiment, addition of same probiotic (i.e., B. amyloliquefaciens CECT 5940) was carried out in two stages. The first stage started from day 7-37, and the second from day 44-71. The assessment of faecal score measured on day 22, 37, 42, 57, 71 and 77 to determine the texture of the stools. Calves received PWM consumed (P 
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology*
  5. Fulltext A Review on Antistaphylococcal Secondary Metabolites from Basidiomycetes
    Vallavan V, Krishnasamy G, Zin NM, Abdul Latif M
    Molecules, 2020 Dec 11;25(24).
    PMID: 33322256 DOI: 10.3390/molecules25245848
    Fungi are a rich source of secondary metabolites with several pharmacological activities such as antifungal, antioxidant, antibacterial and anticancer to name a few. Due to the large number of diverse structured chemical compounds they produce, fungi from the phyla Ascomycota, Basidiomycota and Muccoromycota have been intensively studied for isolation of bioactive compounds. Basidiomycetes-derived secondary metabolites are known as a promising source of antibacterial compounds with activity against Gram-positive bacteria. The continued emergence of antimicrobial resistance (AMR) poses a major challenge to patient health as it leads to higher morbidity and mortality, higher hospital-stay duration and substantial economic burden in global healthcare sector. One of the key culprits for AMR crisis is Staphylococcus aureus causing community-acquired infections as the pathogen develops resistance towards multiple antibiotics. The recent emergence of community strains of S. aureus harbouring methicillin-resistant (MRSA), vancomycin-intermediate (VISA) and vancomycin-resistant (VRSA) genes associated with increased virulence is challenging. Despite the few significant developments in antibiotic research, successful MRSA therapeutic options are still needed to reduce the use of scanty and expensive second-line treatments. This paper provides an overview of findings from various studies on antibacterial secondary metabolites from basidiomycetes, with a special focus on antistaphylococcal activity.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology
  6. Essential oil composition, cytotoxic and antibacterial activities of five Etlingera species from Borneo
    Vairappan CS, Nagappan T, Palaniveloo K
    Nat Prod Commun, 2012 Feb;7(2):239-42.
    PMID: 22474969
    Essential oils obtained by hydrodistillation from the rhizomes of Etlingera pyramidosphaera (K. Schum.) R. M. Sm, E. megalocheilos (Griff.) A.D. Poulsen, comb. nov., E. coccinea (Blume) S. Sakai & Nagam, E. elatior (Jack) R. M. Sm, and E. brevilabrum (Valeton) R. M. Sm were analyzed by GCMS. The highest oil yield was obtained from E. pyramidosphaera (0.45%), followed by E. elatior (0.38%), E. coccinea (0.30%), E. brevilabrum (0.28%) and E. megalocheilos (0.25%). The major constituents of the essential oils were oxygenated monoterpenes, followed by sesquiterpenes, oxygenated sesquiterpenes, oxygenated diterpenes and diterpenes. The essential oils from E. pyramidosphaera and E. brevilabrum exhibited the best cytotoxicity against MCF 7 (LC50: 7.5 +/- 0.5 mg mL(-1)) and HL 60 (LC50: 5.0 mg mL(-1)), respectively. Strong inhibition was also observed for the essential oils of E. coccinea and E. megalocheilos against Staphylococcus aureus (MIC: 8.0 +/- 0.5 mg mL(-1), and 5.0 +/- 0.5 mg mL(-1)) and Streptococcus pyrogenes (MIC: 6.0 +/- 0.5 mg mL(-1) and 8.0 +/- 0.5 mg mL(-1)).
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology*
  7. Fulltext Antibacterial activities of a new brominated diterpene from Borneon Laurencia spp
    Vairappan CS, Ishii T, Lee TK, Suzuki M, Zhaoqi Z
    Mar Drugs, 2010;8(6):1743-9.
    PMID: 20631866 DOI: 10.3390/md8061743
    In our continuous interest to study the diversity of halogenated metabolites of Malaysian species of the red algal genus Laurencia, we examined the chemical composition of five populations of unrecorded Laurencia sp. A new brominated diterpene, 10-acetoxyangasiol (1), and four other known metabolites, aplysidiol (2), cupalaurenol (3), 1-methyl-2,3,5-tribromoindole (4), and chamigrane epoxide (5), were isolated and identified. Isolated metabolites exhibited potent antibacterial activities against clinical bacteria, Staphylococcus aureus, Staphylococcus sp., Streptococcus pyogenes, Salmonella sp. and Vibrio cholerae.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology*
  8. Antibacterial activity of halogenated sesquiterpenes from Malaysian Laurencia spp
    Vairappan CS, Suzuki M, Ishii T, Okino T, Abe T, Masuda M
    Phytochemistry, 2008 Oct;69(13):2490-4.
    PMID: 18718619 DOI: 10.1016/j.phytochem.2008.06.015
    During our studies on Malaysian Laurencia species, brominated metabolites, tiomanene, acetylmajapolene B, and acetylmajapolene A were isolated from an unrecorded species collected at Pulau Tioman, Pahang along with known majapolene B and majapolene A. Acetylmajapolene A was a mixture of diastereomers as in the case of majapolene A. Tiomanene may be a plausible precursor for acetylmajapolenes B and A. In addition, three known halogenated sesquiterpenes and two known halogenated C(15) acetogenins were found from other two unrecorded species collected at Pulau Karah, Terengganu and Pulau Nyireh, Terengganu, respectively. Some of these halogenated metabolites showed moderate antibacterial activity against some marine bacteria.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology*
  9. Potent antibacterial activity of halogenated metabolites from Malaysian red algae, Laurencia majuscula (Rhodomelaceae, Ceramiales)
    Vairappan CS
    Biomol. Eng., 2003 Jul;20(4-6):255-9.
    PMID: 12919806
    Red algae genus Laurencia (Rhodomelaceae, Ceramiales) are known to produce a wide range of chemically interesting secondary halogenated metabolites. This investigation delves upon extraction, isolation, structural elucidation and antibacterial activity of inherently available secondary metabolites of Laurencia majuscula Harvey collected from two locations in waters of Sabah, Malaysia. Two major halogenated compounds, identified as elatol (1) and iso-obtusol (2) were isolated. Structures of these compounds were determined from their spectroscopic data such as IR, 1H-NMR, 13C-NMR and optical rotation. Antibacterial bioassay against human pathogenic bacteria was conducted using disc diffusion (Kirby-Bauer) method. Elatol (1) inhibited six species of bacteria, with significant antibacterial activities against Staphylococcus epidermis, Klebsiella pneumonia and Salmonella sp. while iso-obtusol (2) exhibited antibacterial activity against four bacterial species with significant activity against K. pneumonia and Salmonella sp. Elatol (1) showed equal and better antibacterial activity compared with tested commercial antibiotics while iso-obtusol (2) only equaled the potency of commercial antibiotics against K. pneumonia and Salmonella sp. Further tests conducted using dilution method showed both compounds as having bacteriostatic mode of action against the tested bacteria.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology
  10. Potent antibacterial activity of halogenated compounds against antibiotic-resistant bacteria
    Vairappan CS, Kawamoto T, Miwa H, Suzuki M
    Planta Med, 2004 Nov;70(11):1087-90.
    PMID: 15549668
    Common Gram-positive clinical pathogens are showing an increasing trend for resistance to conventional antimicrobial agents. New drugs with potent antibacterial activities are urgently needed to remediate this problem. Halogenated compounds isolated from several species of the red algae genus Laurencia were examined for their antibacterial activity against 22 strains of human pathogenic bacteria, 7 strains of which were antibiotic-resistant bacteria. Four phenolic sesquiterpenes and a polybrominated indole showed wide spectra of antibacterial activity against Gram-positive bacteria including methicillin-resistant Staphylococcus aureus (MRSA), penicillin-resistant Streptococcus pneumoniae, and vancomycin-resistant Enterococcus faecalis and E. faecium (VRE). In addition, laurinterol and allolaurinterol displayed potent bactericidal activity against three strains of MRSA at 3.13 microg mL(-1), and three strains of vancomycin-susceptible Enterococcus, at 3.13 microg mL(-1) and 6.25 microg mL(-1), respectively.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology*
  11. Bacterial dynamics associated with algal antibacterial substances during post harvest desiccation process of Sargassum stolonifolium Phang et Yoshida
    Vairappan CS
    Indian J Exp Biol, 2003 Aug;41(8):837-45.
    PMID: 15248481
    Brown algae of genus Sargassum are known to produce relatively higher amount of alginic acid. Optimal extraction of this algalcolloid for local consumption requires in-depth studies on post-harvest treatment of the algal fronds. Present investigation endeavors to establish the dynamics and inter-relationship of moisture content and bacteria found on the surface of the alga and alginic acid content during post-harvest desiccation of Sargassum stolonifolium Phang et Yoshida. Harvested fronds were subjected to desiccation for 31 days and bacterial dynamics were monitored with relation to moisture content and water activity index (a(w)). There was 85% decrease in moisture content, however, a(w) showed a more gradual decrease. Total bacterial count increased during the first week and attained maximal value on day 7. Thereafter, a drastic decrease was seen until day 14, followed by a gradual decline. Six species of bacteria were isolated and identified, i.e. Azomonas punctata, Azomonas sp., Escherichia coli, Micrococcus sp., Proteus vulgaris and Vibrio alginolyticus. Calculated ratios for increase in alginic acid content and decrease in moisture content were almost the same throughout the desiccation process, implying that extracellular alginase-producing bacteria did not use the alginic acid produced by the algae as its carbon source. It became apparent that drastic decrease in bacterial count after day 7 could not be attributed to salinity, moisture content, a(w) or lack of carbon source for the bacteria. The possible exposure of these bacteria to algal cell sap which is formed due to the rupture of algal cells was seen as the most likely reason for the drop in bacterial population. Scanning electron microscope (SEM) micrograph taken on day 10 of desiccation showed the presence of cracks and localities where bacteria were exposed to algal cell sap. In vitro antibacterial tests were carried out to verify the effect of algal extracts. Separation and purification of crude algal extracts via bioassay guided separation methodology revealed the identity of active compounds (i.e. gylcolipids and free fatty acids) involved in this inherently available antibacterial defense mechanism during algal desiccation.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology*
  12. Synthesis, spectral analysis and biological evaluation of 2-{[(morpholin-4-yl)ethyl]thio}-5-phenyl/aryl-1,3,4-oxadiazole derivatives
    Ur-Rehman A, Khan SG, Naqvi SAR, Ahmad M, Akhtar N, Bokhari TH, et al.
    Pak J Pharm Sci, 2021 Jan;34(1(Special)):441-446.
    PMID: 34275792
    A series of new derivatives of 4-(2-chloroethyl)morpholine hydrochloride (5) were efficiently synthesized. Briefly, different aromatic organic acids (1a-f) were refluxed to acquire respective esters (2a-f) using conc. H2SO4 as catalyst. The esters were subjected to nucleophillic substitution by monohydrated hydrazine to acquire hydrazides (3a-f). The hydrazides were cyclized with CS2 in the presence of KOH to yield corresponding oxadiazoles (4a-f). Finally, the derivatives, 6a-f, were prepared by reacting oxadiazoles (4a-f) with 5 using NaH as activator. Structures of all the derivatives were elucidated through 1D-NMR EI-MS and IR spectral data. All these molecules were subjected to antibacterial and hemolytic activities and showed good antibacterial and hemolytic potential relative to the reference standards.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology
  13. Development of sodium alginate-pectin biodegradable active food packaging film containing cinnamic acid
    Tong WY, Ahmad Rafiee AR, Leong CR, Tan WN, Dailin DJ, Almarhoon ZM, et al.
    Chemosphere, 2023 Sep;336:139212.
    PMID: 37315854 DOI: 10.1016/j.chemosphere.2023.139212
    Plastics are still the most popular food packaging material and many of them end up in the environment for a long period. Due to packaging material's inability to inhibit microbial growth, beef often contains microorganisms that affect its aroma, colour and texture. Cinnamic acid is categorized as generally recognised as safe and is permitted for use in food. The development of biodegradable food packaging film with cinnamic acid has never been conducted before. This present study was aimed to develop a biodegradable active packaging material for fresh beef using sodium alginate and pectin. The film was successfully developed with solution casting method. The films' thickness, colour, moisture level, dissolution, water vapour permeability, bending strength and elongation at break were comparable to those of polyethylene plastic film in terms of these attributes. The developed film also showed the degradability in soil of 43.26% in a duration of 15 days. Fourier Transform Infrared (FTIR) spectra showed that cinnamic acid was successfully incorporated with the film. The developed film showed significant inhibitory activity on all test foodborne bacteria. On Hohenstein challenge test, a 51.28-70.45% reduction on bacterial growth was also observed. The antibacterial efficacy of the established film by using fresh beef as food model. The meats wrapped with the film showed significant reduction in bacterial load throughout the experimental period by 84.09%. The colour of the beef also showed significant different between control film and edible film during 5 days test. Beef with control film turned into dark brownish and beef with cinnamic acid turn into light brownish. Sodium alginate and pectin film with cinnamic acid showed good biodegradability and antibacterial activity. Further studies can be conducted to investigate the scalability and commercial viability of this environmental-friendly food packaging materials.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology
  14. Nanoparticle-laden contact lens for controlled release of vancomycin with enhanced antibiotic efficacy
    Tong WY, Tan WN, Kamarul Azizi MA, Leong CR, El Azab IH, Lim JW, et al.
    Chemosphere, 2023 Oct;338:139492.
    PMID: 37451643 DOI: 10.1016/j.chemosphere.2023.139492
    Vancomycin is the last resort antibiotic for the treatment of severe bacterial keratitis. Its clinical application is limited due to its hydrophilicity and high molecular weight. To overcome this, this study aims to develop nanoparticles-laden contact lens for controlled ocular delivery of vancomycin. Polyvinyl alcohol (PVA) was used as encapsulant material. The nanoparticles had a negative surface charge and an average size of 147.6 nm. A satisfactory encapsulation efficiency (61.24%) was obtained. The release profile was observed to be slow and sustained, with a release rate of 1.29 μL mg-1 h-1 for 48 h. Five out of 6 test bacteria were suppressed by vancomycin nanoparticles-laden contact lens. Vancomycin is generally ineffective against Gram-negative bacteria and unable to pass through the outer membrane barrier. In this study, vancomycin inhibited Proteus mirabilis and Pseudomonas aeruginosa. Nano-encapsulation enables vancomycin to penetrate the Gram-negative cell wall and further destroy the bacterial cells. On Hohenstein challenge test, all test bacteria exhibited significant reduction in growth when exposed to vancomycin nanoparticles-laden contact lens. This study created an effective and long-lasting vancomycin delivery system via silicone hydrogel contact lenses, by using PVA as encapsulant. The antibiotic efficacy and vancomycin release should be further studied using ocular in vivo models.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology
  15. In vitro antimicrobial efficacy of Cassia alata (Linn.) leaves, stem, and root extracts against cellulitis causative agent Staphylococcus aureus
    Toh SC, Lihan S, Bunya SR, Leong SS
    BMC Complement Med Ther, 2023 Mar 18;23(1):85.
    PMID: 36934252 DOI: 10.1186/s12906-023-03914-z
    BACKGROUND: Cellulitis is a common skin disease encountered in medical emergencies in hospitals. It can be treated using a combination of antibiotics therapy; however, the causative agent Staphylococcus aureus has been reported to develop resistance towards the currently used antibiotics. Therefore, the search for more alternative herbal origin antimicrobial agents is critical.

    AIM: In this study, maceration and Soxhlet extraction of the whole plant of Cassia alata Linn. (leaves, roots, and stem) were performed using four solvents with different polarities, namely n-hexane, ethyl acetate, ethanol and distilled water. The crude extracts were screened using agar well diffusion, colorimetric broth microdilution, grid culture and bacterial growth curve analysis against Staphylococcus aureus. The phytochemicals in the crude extracts were identified using Gas Chromatography-Mass Spectrometry (GC-MS).

    RESULTS: Agar-well diffusion analysis revealed that extraction using ethyl acetate showed the largest inhibition zone with an average diameter of 15.30 mm (root Soxhlet extract) followed by 14.70 mm (leaf Soxhlet extract) and 13.70 mm (root maceration extract). The lowest minimum inhibitory and minimum bactericidal concentration in root Soxhlet extract using ethyl acetate was 0.313 and 0.625 µg µL-1, respectively. Our study proved that crude extract of the plant suppressed the growth of S. aureus as evidenced from a significant regression extension (p anti-inflammatory activities.

    CONCLUSION: Ethyl acetate crude extract was better than the other investigated solvents. The root and stem of C. alata showed significant antimicrobial efficacy against S. aureus in this study. The remaining 56 out of 88 phytochemicals of the plant should be intensively studied for more medicinal uses.

    Matched MeSH terms: Anti-Bacterial Agents/pharmacology
  16. Beneficial features of pediococcus: from starter cultures and inhibitory activities to probiotic benefits
    Todorov SD, Dioso CM, Liong MT, Nero LA, Khosravi-Darani K, Ivanova IV
    World J Microbiol Biotechnol, 2022 Nov 08;39(1):4.
    PMID: 36344843 DOI: 10.1007/s11274-022-03419-w
    Pediococci are lactic acid bacteria (LAB) which have been used for centuries in the production of traditional fermented foods. There fermentative abilities were explored by the modern food processing industry in use of pediococci as starter cultures, enabling the production of fermented foods with distinct characteristics. Furthermore, some pediococci strains can produce bacteriocins and other antimicrobial metabolites (AMM), such as pediocins, which are increasingly being explored as bio-preservatives in various food matrices. Due to their versatility and inhibitory spectrum, pediococci bacteriocins and AMM are being extensively researched not only in the food industry, but also in veterinary and human medicine. Some of the pediococci were evaluated as potential probiotics with different beneficial areas of application associated with human and other animals' health. The main taxonomic characteristics of pediococci species are presented here, as well as and their potential roles and applications as starter cultures, as bio-preservatives and as probiotic candidates.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology
  17. Prevalence of methicillin-resistant Staphylococcus aureus and its antibiotic susceptibility pattern in a tertiary care hospital
    Tiwari S, Sahu M, Rautaraya B, Karuna T, Mishra SR, Bhattacharya S
    J Indian Med Assoc, 2011 Nov;109(11):800-1.
    PMID: 22666934
    Methicillin-resistant Staphylococcus aureus (MRSA) emerged as a nosocomial pathogen in early 1960s, causing Increasing number of outbreaks in 19708, first reported in a teaching hospital in Malaysia in 1972, causing increased mortality, morbidity, and healthcare costs. Aim of this study is to screen out MRSA from various clinical samples and to see their antibiotic susceptibility pattern. From May 2008 to May 2009, 204 S aureus strains were isolated, out of which 114 (55.8%) were MRSA, and rest methicillin-sensitive Staphylococcus aureus (MSSA). Most of the MRSA strains were obtained from pus (45%) followed by urine (20.5%). Frequency of isolating MRSA were maximum in catheter tip (80%) followed by blood (66.7%) and pus (58.7%). MRSA strains were showing 100% sensitivity to vancomycin and Iinezolid, whereas 92.9% to teicoplanin. Therefore it is concluded that antibiotics other than vancomycin can be used as anti-MRSA agents after sensitivity test, as well as irrational and indiscriminate use of antibiotics can be avoided.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology*
  18. Zingiber officinale Roscoe Essential Oils-Loaded Chitosan Nanoparticles with Enhanced Bactericidal Efficacy against Burkholderia glumae in Rice
    Tiran Gunasena M, Hussein MZ, Ali A, Wahab MAA, Bashir Kutawa A, Rafif A, et al.
    Chem Biodivers, 2023 Dec;20(12):e202300686.
    PMID: 37905394 DOI: 10.1002/cbdv.202300686
    Ginger essential oils (GEO) shows exceptional antimicrobial properties against plant pathogens. Due to its high volatility and low stability, it requires encapsulation to retain its effective properties. The GEO-Chitosan (GEO-CS) nanobactericide was developed using the ionic gelation method. The nanobactericides show particle diameters of 465, 28, 35, 48 and 500 nm when sodium tripolyphosphate (TPP) concentrations used in the preparation were 0.0, 0.5, 1.0, 2.0 and 4.0 %, respectively. The X-ray diffraction and the UV-vis studies revealed that the GEO was encapsulated into the chitosan nanoparticles with an encapsulation efficiency of around 46 % and a loading capacity of 27-34 %. The antibacterial activity of GEO-chitosan nanobactericide against Burkholderia glumae (Bg) was found to be 7.5-11.8 mm, with minimum inhibitory concentration and minimum bactericidal concentration values of 15.6 μl/mL and 31.25 μl/mL, respectively. Hence, these findings indicate that the prepared GEO-CS nanobactericides were found to be effective against Bg. This preliminary study is toward the development of new agronanobactericides using a natural product to control Bg.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology
  19. Macrorestriction analysis and antimicrobial susceptibility profiling of Salmonella enterica at a University Teaching Hospital, Kuala Lumpur
    Tiong V, Thong KL, Yusof MY, Hanifah YA, Sam JI, Hassan H
    Jpn J Infect Dis, 2010 Sep;63(5):317-22.
    PMID: 20858996
    The genetic diversity and antimicrobial resistance rates of clinical Salmonella isolates (2007-2008) at the University of Malaya Medical Centre, Kuala Lumpur, were investigated and the genetic diversity of the isolates was determined by pulsed-field gel electrophoresis (PFGE) and repetitive extragenic palindromic (REP)-PCR. XbaI-PFGE analysis generated 57 profiles (Dice coefficient, F=0.08-1.00), whereas REP-PCR using the REP primer generated only 35 (F=0.34-1.00). PFGE was therefore the more discriminative and reproducible method for assessing the genetic diversity of salmonellae. The antibiograms of 78 Salmonella isolates were assessed against 19 antimicrobials using the disk diffusion method. Twenty serotypes were identified, with the most common being S. Enteritidis (18%) followed by S. Typhimurium (14%), S. Paratyphi B var Java (9%), S. Weltevreden (9%), and S. Corvallis (9%). A total of 38 resistant profiles were defined, with 53.8% of the isolates being resistant to three or more antimicrobials. The highest resistance rates were observed for cephalothin (55.1%), tetracycline (47.4%), and nalidixic acid (35.9%). The presence of multidrug-resistant Salmonella strains is a cause for concern as it may limit the treatment of severe salmonellosis. One multidrug-resistant S. Enteritidis strain was a putative extended-spectrum beta-lactamase producer, based on a double disk diffusion analysis, and was resistant to ceftriaxone (MIC>32 microg/mL). The data generated by this study will contribute towards epidemiological monitoring and investigations of Salmonella infections in Malaysia.
    Matched MeSH terms: Anti-Bacterial Agents/pharmacology*
  20. Prevalence of AmpC beta-lactamase and extended spectrum beta-lactamase co-producer in Escherichia coli and Klebsiella species in a teaching hospital
    Ting SMV, Ismail Z, Hanafiah A
    Malays J Pathol, 2024 Apr;46(1):79-89.
    PMID: 38682847
    INTRODUCTION: Beta-lactamase producing bacterial infection has been on surge due to selection pressure and injudicious antibiotics usage. Organisms that co-produced more than one beta lactamase enzyme posed diagnostic challenges which may result in inadequate treatment. To date, there is no standardised guideline offering phenotypic detection of AmpC β-lactamase. The purpose of this study was to determine the prevalence of ESBLs, AmpC β-lactamase and co-producer organisms in a teaching hospital.

    MATERIALS AND METHODS: Three hundred and four isolates of E. coli and Klebsiella sp. had been selected via convenient sampling. These isolates were identified using conventional laboratory methods and their antimicrobial susceptibilities were determined using disc diffusion method. Those isolates were then proceeded with ESBL confirmatory test, cloxacillin-containing Muller Hinton confirmatory test, modified double disk synergy test and AmpC disk test.

    RESULTS: Out of 304 isolates, 159 isolates were E. coli and 145 were Klebsiella sp. The prevalence of organisms which co-produced AmpC β-lactamase and ESBL enzymes were 3.0%. Besides that, 39 cefoxitin resistant and three cefoxitin susceptible isolates (13.8%) were proven to produce AmpC β-lactamase through AmpC disk test. Through the CLSI confirmatory test, 252 (82.9%) isolates were identified as ESBLs producers and the prevalence increased slightly when cloxacillin-containing Muller Hinton were used. Only three ESBLs positive organisms were positive for modified double disk synergy test.

    CONCLUSION: Distinguishing between AmpC β-lactamase and ESBL-producing organisms has epidemiological significance as well as therapeutic importance. Moreover, AmpC β-lactamase and ESBLs co-producing organisms can lead to false negative ESBL confirmatory test. Therefore, knowing the local prevalence can guide the clinician in navigating the treatment.

    Matched MeSH terms: Anti-Bacterial Agents/pharmacology
Related Terms
Filters
Contact Us

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

External Links