Displaying publications 101 - 120 of 689 in total

Abstract:
Sort:
  1. Fulltext Antibacterial activities of the extracts, fractions and isolated compounds from Canarium patentinervium Miq. against bacterial clinical isolates
    Mogana R, Adhikari A, Tzar MN, Ramliza R, Wiart C
    BMC Complement Med Ther, 2020 Feb 14;20(1):55.
    PMID: 32059725 DOI: 10.1186/s12906-020-2837-5
    BACKGROUND: Canarium patentinervium leaves are used by the local indigenous people of Malaysia for wound healing. The current study is undertaken to screen the comprehensive antibacterial activity of the leaves and barks extracts, fractions and isolated compounds from this plant. Bioassay guided fractionation was also undertaken to deeply evaluate the antibacterial activity of the water fraction of the leaves extract. This is to provide preliminary scientific evidence to the ethnopharmacology usage of this plant by investigating antibacterial properties of the plant and its isolated constituents.

    METHODS: Bio-assay guided fractionation and subsequent isolation of compounds using open column chromatography. The antibacterial activity against gram positive and gram negative ATCC strain and resistant clinical strains were evaluated using microtiter broth dilution method to determine minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and time-kill assay. The chemical structure of the isolated compounds from the water fraction of the ethanol extract of leaves was elucidated using Nuclear Magnetic Resonance (NMR).

    RESULTS: The ethanol extract of the leaves and barks showed antimicrobial activity against all four ATCC and eight clinical isolates. The ethanol extract of the leaves and the corresponding water fraction had good activity against MRSA S. aureus. (MIC: 250 μg/ml) and had bactericidal effect on eight of the clinical strains (MSSA,MRSA, oxacillin-resistant CONS, oxacillin-sensitive CONS, Enterococcus faecalis, Klebsiela species, Kleb pneumoniae ESBL and Candida parapsilosis). Further phytochemical investigation of the water fraction of the crude ethanol extract of leaves afforded compound 7 (hyperin) and compound 8 (cynaroside) that had bactericidal activity against tested bacterial species (MIC 50 μg/ml and 100 μg/ml). The two compounds were isolated from this genus for the first time.

    CONCLUSIONS: These results may provide a rational support for the traditional use of Canarium patentinervium Miq. in infections and wound healing, since the antimicrobial compounds isolated were also present in the leaves extract.

    Matched MeSH terms: Staphylococcus aureus; Methicillin-Resistant Staphylococcus aureus
  2. Fulltext In Vitro Influence of ZnO, CrZnO, RuZnO, and BaZnO Nanomaterials on Bacterial Growth
    Abdallah EM, Modwi A, Al-Mijalli SH, Mohammed AE, Idriss H, Omar AS, et al.
    Molecules, 2022 Nov 28;27(23).
    PMID: 36500402 DOI: 10.3390/molecules27238309
    In this work, ZnO, CrZnO, RuZnO, and BaZnO nanomaterials were synthesized and characterized in order to study their antibacterial activity. The agar well diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) assays were used to determine the antibacterial activity of the fabricated nanomaterials against Staphylococcus aureus ATCC 29213, Escherichia coli ATCC35218, Klebsiella pneumoniae ATCC 7000603, and Pseudomonas aeruginosa ATCC 278533. The well-diffusion test revealed significant antibacterial activity against all investigated bacteria when compared to vancomycin at a concentration of 1 mg/mL. The most susceptible bacteria to BaZnO, RuZnO, and CrZnO were Staphylococcus aureus (15.5 ± 0.5 mm), Pseudomonas aeruginosa (19.2 ± 0.5 mm), and Pseudomonas aeruginosa (19.7 ± 0.5), respectively. The MIC values indicated that they were in the range of 0.02 to 0.2 mg/mL. The MBC values showed that the tested bacteria's growth could be inhibited at concentrations ranging from 0.2 to 2.0 mg/mL. According to the MBC/MIC ratio, BaZnO, RuZnO, and CrZnO exhibit bacteriostatic effects and may target bacterial protein synthesis based on the results of the tolerance test. This study shows the efficacy of the above-mentioned nanoparticles on bacterial growth. Further biotechnological and toxicological studies on the nanoparticles fabricated here are recommended to benefit from these findings.
    Matched MeSH terms: Staphylococcus aureus*
  3. Lactoferrin modulates the biofilm formation and bap gene expression of methicillin-resistant Staphylococcus epidermidis
    Khanum R, Chung PY, Clarke SC, Chin BY
    Can J Microbiol, 2023 Feb 01;69(2):117-122.
    PMID: 36265186 DOI: 10.1139/cjm-2022-0135
    Lactoferrin is an innate glycoprotein with broad antibacterial and antibiofilm properties. The autonomous antibiofilm activity of lactoferrin against Gram-positive bacteria is postulated to involve the cell wall and biofilm components. Thus, the prevention of biomass formation and eradication of preformed biofilms by lactoferrin was investigated using a methicillin-resistant Staphylococcus epidermidis (MRSE) strain. Additionally, the ability of lactoferrin to modulate the expression of the biofilm-associated protein gene (bap) was studied. The bap gene regulates the production of biofilm-associated proteins responsible for bacterial adhesion and aggregation. In the in vitro biofilm assays, lactoferrin prevented biofilm formation and eradicated established biofilms for up to 24 and 72 h, respectively. Extensive eradication of MRSE biofilm biomass was accompanied by the significant upregulation of bap gene expression. These data suggest the interaction of lactoferrin with the biofilm components and cell wall of MRSE, including the biofilm-associated protein.
    Matched MeSH terms: Staphylococcus epidermidis/genetics
  4. Fulltext Recent Advances in Pyridine Scaffold: Focus on Chemistry, Synthesis, and Antibacterial Activities
    Islam MB, Islam MI, Nath N, Emran TB, Rahman MR, Sharma R, et al.
    Biomed Res Int, 2023;2023:9967591.
    PMID: 37250749 DOI: 10.1155/2023/9967591
    Multidrug-resistant (MDR) pathogens have created a fatal problem for human health and antimicrobial treatment. Among the currently available antibiotics, many are inactive against MDR pathogens. In this context, heterocyclic compounds/drugs play a vital role. Thus, it is very much essential to explore new research to combat the issue. Of the available nitrogen-bearing heterocyclic compounds/drugs, pyridine derivatives are of special interest due to their solubility. Encouragingly, some of the newly synthesized pyridine compounds/drugs are found to inhibit multidrug-resistant S. aureus (MRSA). Pyridine scaffold bearing poor basicity generally improves water solubility in pharmaceutically potential molecules and has led to the discovery of numerous broad-spectrum therapeutic agents. Keeping these in mind, we have reviewed the chemistry, recent synthetic techniques, and bacterial preventative activity of pyridine derivatives since 2015. This will facilitate the development of pyridine-based novel antibiotic/drug design in the near future as a versatile scaffold with limited side effects for the next-generation therapeutics.
    Matched MeSH terms: Methicillin-Resistant Staphylococcus aureus*
  5. The phenotypes and genotypes associated with biofilm formation among methicillin-susceptible Staphylococcus aureus (MSSA) isolates collected from a tertiary hospital in Terengganu, Malaysia
    Jones SU, Chew CH, Yeo CC, Abdullah FH, Othman N, Kee BP, et al.
    Int Microbiol, 2023 Nov;26(4):841-849.
    PMID: 36805382 DOI: 10.1007/s10123-023-00335-3
    Methicillin-susceptible Staphylococcus aureus (MSSA) is an important nosocomial pathogen worldwide. This study aims to investigate the in vitro biofilm-forming ability of clinical MSSA isolated from various sources in the main public tertiary referral hospital in Terengganu, Malaysia and to detect the presence of biofilm-associated and regulatory genes among these isolates. A total of 104 MSSA isolates [pus (n = 75), blood (n = 24), respiratory secretions (n = 2), eye (n = 2), and urine (n = 1)] were investigated for slime production and biofilm formation using Congo red agar and crystal violet microtitre plate, respectively. Fifteen MSSA isolates with varying degrees of biofilm formation were selected for validation via a real-time cell analyser. All isolates were screened for microbial surface components recognising adhesive matrix molecules (MSCRAMM) and accessory gene regulator (agr) using polymerase chain reaction assay. A total of 76.0% (79/104) isolates produced slime layer, while all isolates developed biofilm as follows: 52.8% (55/104) strong biofilm producers, 40.4% (42/104) intermediate biofilm producers, and 6.7% (7/104) weak biofilm producers. A total of 98.1% (102/104) isolates carried at least one of the screened MSCRAMM gene(s) with the eno gene detected at the highest rate (87.5%, 91/104), while the sasG gene was significantly associated with strong biofilm production (p = 0.015). Three agr groups, 1, 2, and 3, were detected among the MSSA isolates with a predominance of agr-3 (32.7%, 34/104). In conclusion, biofilm formation varied greatly among clinical MSSA isolates, and the presence of sasG gene and agr-1 may play important role in initiating MSSA infections via biofilm formation.
    Matched MeSH terms: Staphylococcus aureus/genetics
  6. Fulltext Evaluation of methicillin-resistant Staphylococcus aureus (MRSA) bacteremia: Epidemiology, clinical characteristics, and outcomes in the older patients in a tertiary teaching hospital in Malaysia
    Hasmukharay K, Ngoi ST, Saedon NI, Tan KM, Khor HM, Chin AV, et al.
    BMC Infect Dis, 2023 Apr 18;23(1):241.
    PMID: 37072768 DOI: 10.1186/s12879-023-08206-y
    BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) bacteremia is a major concern in the global healthcare system. However, data from Asian regions dealing with the singularity of this infection in older persons is lacking. We aimed to identify the differences in the clinical characteristics and outcomes of MRSA bacteremia between adults aged 18-64 and ≥ 65 years.

    METHODS: A retrospective study cohort was conducted at the University Malaya Medical Centre (UMMC) on cases of MRSA bacteremia from 2012 to 2016. Patient demographic and clinical data were collected for risk factors analyses.

    RESULTS: New cases of MRSA bacteremia showed a trend of increase from 0.12 to 100 admissions in 2012 to 0.17 per 100 admissions in 2016 but a drop was observed in 2014 (0.07 per 100 admissions). Out of the 275 patients with MRSA bacteremia, 139 (50.5%) patients were aged ≥ 65 years old. Co-morbidities and severity at presentation were significantly higher among older adults, including diabetes mellitus (p = 0.035), hypertension (p = 0.001), and ischemic heart disease (p 

    Matched MeSH terms: Methicillin-Resistant Staphylococcus aureus*
  7. Fulltext Characterization of bioactive compounds produced by endophytic fungi isolated from Gynura procumbens (Sambung Nyawa)
    Jamal HAA, Husaini A, Sing NN, Roslan HA, Zulkharnain A, Akinkunmi WA
    Braz J Microbiol, 2022 Dec;53(4):1857-1870.
    PMID: 36109458 DOI: 10.1007/s42770-022-00827-w
    This research evaluates the bioactivity of twelve endophytic fungi successfully isolated and characterised from Gynura procumbens. The fungal extracts displayed inhibitory activity against Staphylococcus aureus, Pseudomonas aeruginosa, Methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli and Salmonella typhi with the MIC and MBC of 5000 µg/mL. High antioxidant activity using DPPH free radical scavenging assay with inhibition of 86.6% and IC50 value of 104.25 ± 18.51 µg/mL were exhibited by ethyl acetate extract of Macrophomina phaseolina SN6. In contrast, the highest scavenging activity percentage of methanolic extract was exhibited by Mycoleptodiscus indicus SN4 (50.0%). Besides that, the highest ferric reducing antioxidant power (FRAP) value of ethyl acetate and methanolic extract was recorded from M. phaseolina SN6 (239.9 mg Fe (II)/g) and M. indicus SN4 (44.7 mg Fe (II)/g), respectively. Total phenolic content (TPC) and total flavonoid content (TFC) of ethyl acetate and methanolic fungal extracts were determined using Folin-Ciocalteu and aluminium chloride, respectively. The highest TPC for ethyl acetate and methanolic extracts were exhibited by Colletotrichum gloeosporioides SN11 (87.0 mg GAE/g) and M. indicus SN4 (35.0 mg GAE/g), whereas the highest TFC of ethyl acetate and methanolic extracts were showed by M. phaseolina SN6 (122.8 mg QCE/g) and M. indicus SN4 (60.4 mg QCE/g), respectively. Bioactive metabolites of isoelemicin (50.8%), terpinen-4-ol (21.5%), eucalyptol (24.3%), oleic acid (19.8%) and β-pinene (10.9%) were detected. Owing to the higher content of phytochemicals represented in the ethyl acetate extract of M. phaseolina, SN6 is therefore identified to be a superior candidate in exhibiting strong antioxidant and antimicrobial properties be fit for further pharmaceutical studies.
    Matched MeSH terms: Methicillin-Resistant Staphylococcus aureus*
  8. Antimicrobial activity of essential oils of Curcuma longa and Syzygium aromaticum against multiple drug-resistant pathogenic bacteria
    Zeshan MQ, Ashraf M, Omer MO, Anjum AA, Ali MA, Najeeb M, et al.
    Trop Biomed, 2023 Jun 01;40(2):174-182.
    PMID: 37650404 DOI: 10.47665/tb.40.2.008
    The present study was conducted to investigate the antimicrobial potential of essential oils of Curcuma longa and Syzygium aromaticum against multidrug-resistant pathogenic bacteria. Four identified bacterial isolates including Methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, Klebsiella pneumoniae, and Acinetobacter baumannii were selected and their antibiotic sensitivity was checked by disc diffusion assay. C. longa and S. aromaticum were subjected to steam distillation to obtain their essential oils. The crude essential oils were fractioned by employing column chromatography. Crude essential oils and their fractions were evaluated for their antibacterial activity by agar well diffusion assay and minimum inhibitory concentrations were calculated. All the selected bacterial isolates showed resistance to three or more than three antibiotic groups and were declared as multidrugresistant (MDRs). Crude essential oils of C. longa and S. aromaticum exhibited antimicrobial activity against all selected isolates but S. aromaticum activity was better than the C. longa with a maximum 19.3±1.50 mm zone of inhibition against A. baumannii at 1.04 µL/mL MIC. GC/MS analysis revealed the abundance of components including eugenol, eugenyl acetate, b- caryophyllene, and a- Humulene in both crude oil and fractions of S. aromaticum. While the main components of C. longa essential oil were Ar-tumerone, a-tumerone, b- Tumerone, I-Phellandrene, a-zingibirene, b- sesquiphellandrene, and p- Cymene. This study highlights that plant-based essential oils could be a promising alternative to antibiotics for which pathogens have developed resistance. C. longa and S. aromaticum carry compounds that have antimicrobial potential against multiple drug-resistant bacteria including MRSA. E. coli, K. pneumoniae and A. baumannii.
    Matched MeSH terms: Methicillin-Resistant Staphylococcus aureus*
  9. Effects of Phomopsidione on the Viability, Virulence, and Metabolites Profile of Methicillin-Resistant Staphylococcus aureus (MRSA)
    Wei YM, Tong WY, Tan JS, Lim V, Leong CR, Tan WN
    Curr Microbiol, 2024 Mar 10;81(4):108.
    PMID: 38461425 DOI: 10.1007/s00284-024-03627-7
    Methicillin-resistant Staphylococcus aureus (MRSA) infections have become one of the most threatening multidrug-resistant pathogens. Thus, an ongoing search for anti-MRSA compounds remains an urgent need to effectively treating MRSA infections. Phomopsidione, a novel antibiotic isolated from Diaporthe fraxini, has previously demonstrated potent anti-candidal activity. The present study aimed to investigate the effects of phomopsidione on the viability, virulence, and metabolites profile of MRSA. MRSA was sensitive to phomopsidione in a concentration-dependent manner. Phomopsidione exhibited minimum inhibitory concentration and minimum bactericidal concentration of 62.5 and 500.00 µg/mL against MRSA on broth microdilution assay. The compound showed significant reduction in virulence factors production including extracellular polymeric substances quantification, catalase, and lipase. An untargeted metabolomics analysis using liquid chromatography-high resolution mass spectrometry revealed a significant difference in the metabolites profile of MRSA with 13 putatively identified discriminant metabolites. The present study suggested the potential of phomopsidione as a promising anti-MRSA agent.
    Matched MeSH terms: Methicillin-Resistant Staphylococcus aureus*
  10. Fulltext GC-MS Based Metabolite Profiling, Antioxidant and Antimicrobial Properties of Different Solvent Extracts of Malaysian Plectranthus amboinicus Leaves
    Swamy MK, Arumugam G, Kaur R, Ghasemzadeh A, Yusoff MM, Sinniah UR
    Evid Based Complement Alternat Med, 2017;2017:1517683.
    PMID: 28424737 DOI: 10.1155/2017/1517683
    This study evaluates the phytochemistry, antioxidant, and antimicrobial effects of Plectranthus amboinicus leaves extracted in different solvents. The methanol extract contained the highest total phenolic (94.37 ± 1.24 mg GAE/g) and flavonoid contents (26.90 ± 1.35 mg RE/g) and exhibited the highest DPPH scavenging activity (90.13 ± 3.32%) followed by the acetone extract (80.23 ± 3.26%) at 500 μg/mL concentration. Similarly, the highest ferric ion reduction potential (849.63 ± 30.95 μM of Fe (II)/g dry weight) was exhibited by the methanol extract followed by the acetone extract (695.92 ± 25.44 μM of Fe (II)/g dry weight). The methanol extract showed greater antimicrobial activity against all the tested pathogens (Bacillus subtilis, Methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans). However, both hexane and acetone extracts failed to inhibit E. coli. S. aureus and C. albicans were more susceptible to all the extracts. Further, GC-MS analysis confirmed the occurrence of a total 46 phytocompounds in different solvent extracts. Some of the major compounds included carvacrol (37.7%), tetracontane (16.6%), squalene (15.6%), tetrapentacontane (13.7%), and Phytol (12.9%). In conclusion, extraction solvents influenced the recovery of phytocompounds and the highest pharmacological activities of the methanol extract could be correlated to the presence of additional bioactive compounds.
    Matched MeSH terms: Staphylococcus aureus; Methicillin-Resistant Staphylococcus aureus
  11. Harnessing the photocatalytic potential of bismuth ferrite-activated carbon nanocomposite (BFO-AC) for Staphylococcus aureus decontamination under visible light
    Daub NA, Aziz F, Mhamad SA, Chee DNA, Jaafar J, Yusof N, et al.
    Environ Sci Pollut Res Int, 2024 Mar;31(11):16629-16641.
    PMID: 38321283 DOI: 10.1007/s11356-024-32261-w
    In response to the escalating global issue of microbial contamination, this study introduces a breakthrough photocatalyst: bismuth ferrite-activated carbon (BFO-AC) for visible light-driven disinfection, specifically targeting the Gram-positive bacterium Staphylococcus aureus (S. aureus). Employing an ultrasonication method, we synthesized various BFO-AC ratios and subjected them to comprehensive characterization. Remarkably, the bismuth ferrite-activated carbon 1:1.5 ratio (BA 1:1.5) nanocomposite exhibited the narrowest band gap of 1.86 eV. Notably, BA (1:1.5) demonstrated an exceptional BET surface area of 862.99 m2/g, a remarkable improvement compared to pristine BFO with only 27.61 m2/g. Further investigation through FE-SEM unveiled the presence of BFO nanoparticles on the activated carbon surface. Crucially, the photocatalytic efficacy of BA (1:1.5) towards S. aureus reached its zenith, achieving complete inactivation in just 60 min. TEM analysis revealed severe damage and rupture of bacterial cells, affirming the potent disinfection capabilities of BA (1:1.5). This exceptional disinfection efficiency underscores the promising potential of BA (1:1.5) for the treatment of contaminated water sources. Importantly, our results underscore the enhanced photocatalytic performance with an increased content of activated carbon, suggesting a promising avenue for more effective microorganism inactivation.
    Matched MeSH terms: Staphylococcus aureus*
  12. A starch/gelatin-based Halochromic film with black currant anthocyanin and Nanocellulose-stabilized cinnamon essential oil Pickering emulsion: Towards real-time Salmon freshness assessment
    Lim HJ, Tang SY, Chan KW, Manickam S, Yu LJ, Tan KW
    Int J Biol Macromol, 2024 Aug;274(Pt 1):133329.
    PMID: 38908640 DOI: 10.1016/j.ijbiomac.2024.133329
    Neoterically, food packaging systems designed solely for prolonging shelf life or monitoring freshness could not fulfil the dynamic demands of consumers. In this current investigation, using the solvent casting method, a versatile halochromic indicator was created by integrating black currant anthocyanin and cinnamon essential oil-loaded Pickering emulsion into a starch/gelatin matrix. The resulting indicator film underwent scrutiny for its structural, pH-sensitive, antioxidant, and antimicrobial attributes. Unexpectedly, the amalgamation of anthocyanin and essential oil led to decreased antioxidant activity, dropping from 73.23 ± 2.17 to 28.87 ± 2.50 mg Trolox equivalent/g sample. Additionally, no discernible antimicrobial properties were detected in the composite film sample against both Staphylococcus aureus and Escherichia coli. Fourier transform infrared analyses unveiled robust intermolecular interactions among the film-forming components, providing insights into the observed antagonistic effect. The indicator film displayed distinctive colour changes corresponding to the fresh (greyish-brown), onset of decomposition (khaki), and spoiled (dark green) stages of the stored fish sample. This highlights its promising potential for providing real-time indications of food spoilage. These findings are important for the efficient design of composite films incorporating anthocyanins and essential oils. They serve as a guide towards their potential use as multifunctional packaging materials in the food industry.
    Matched MeSH terms: Staphylococcus aureus/drug effects
  13. Fulltext Bioactive Compounds of Ganoderma boninense Inhibited Methicillin-Resistant Staphylococcus aureus Growth by Affecting Their Cell Membrane Permeability and Integrity
    Chan YS, Chong KP
    Molecules, 2022 Jan 27;27(3).
    PMID: 35164103 DOI: 10.3390/molecules27030838
    Some species of Ganoderma, such as G. lucidum, are well-known as traditional Chinese medicine (TCM), and their pharmacological value was scientifically proven in modern days. However, G. boninense is recognized as an oil palm pathogen, and its biological activity is scarcely reported. Hence, this study aimed to investigate the antibacterial properties of G. boninense fruiting bodies, which formed by condensed mycelial, produced numerous and complex profiles of natural compounds. Extract was cleaned up with normal-phase SPE and its metabolites were analyzed using liquid chromatography-mass spectrometry (LCMS). From the disc diffusion and broth microdilution assays, strong susceptibility was observed in methicillin-resistant Staphylococcus aureus (MRSA) in elute fraction with zone inhibition of 41.08 ± 0.04 mm and MIC value of 0.078 mg mL-1. A total of 23 peaks were detected using MS, which were putatively identified based on their mass-to-charge ratio (m/z), and eight compounds, which include aristolochic acid, aminoimidazole ribotide, lysine sulfonamide 11v, carbocyclic puromycin, fenbendazole, acetylcaranine, tigecycline, and tamoxifen, were reported in earlier literature for their antimicrobial activity. Morphological observation via scanning electron microscope (SEM), cell membrane permeability, and integrity assessment suggest G. boninense extract induces irreversible damage to the cell membrane of MRSA, thus causing cellular lysis and death.
    Matched MeSH terms: Methicillin-Resistant Staphylococcus aureus/metabolism*
  14. Fulltext Chemical Composition, Antioxidant, Antibacterial, and Antibiofilm Activities of Backhousia citriodora Essential Oil
    Lim AC, Tang SGH, Zin NM, Maisarah AM, Ariffin IA, Ker PJ, et al.
    Molecules, 2022 Jul 31;27(15).
    PMID: 35956846 DOI: 10.3390/molecules27154895
    The essential oil of Backhousia citriodora, commonly known as lemon myrtle oil, possesses various beneficial properties due to its richness in bioactive compounds. This study aimed to characterize the chemical profile of the essential oil isolated from leaves of Backhousia citriodora (BCEO) and its biological properties, including antioxidant, antibacterial, and antibiofilm activities. Using gas chromatography-mass spectrometry, 21 compounds were identified in BCEO, representing 98.50% of the total oil content. The isomers of citral, geranial (52.13%), and neral (37.65%) were detected as the main constituents. The evaluation of DPPH radical scavenging activity and ferric reducing antioxidant power showed that BCEO exhibited strong antioxidant activity at IC50 of 42.57 μg/mL and EC50 of 20.03 μg/mL, respectively. The antibacterial activity results showed that BCEO exhibited stronger antibacterial activity against Gram-positive bacteria (Staphylococcus aureus and Staphylococcus epidermidis) than against Gram-negative bacteria (Escherichia coli and Klebsiella pneumoniae). For the agar disk diffusion method, S. epidermidis was the most sensitive to BCEO with an inhibition zone diameter of 50.17 mm, followed by S. aureus (31.13 mm), E. coli (20.33 mm), and K. pneumoniae (12.67 mm). The results from the microdilution method showed that BCEO exhibited the highest activity against S. epidermidis and S. aureus, with the minimal inhibitory concentration (MIC) value of 6.25 μL/mL. BCEO acts as a potent antibiofilm agent with dual actions, inhibiting (85.10% to 96.44%) and eradicating (70.92% to 90.73%) of the biofilms formed by the four tested bacteria strains, compared with streptomycin (biofilm inhibition, 67.65% to 94.29% and biofilm eradication, 49.97% to 89.73%). This study highlights that BCEO can potentially be a natural antioxidant agent, antibacterial agent, and antibiofilm agent that could be applied in the pharmaceutical and food industries. To the best of the authors' knowledge, this is the first report, on the antibiofilm activity of BCEO against four common nosocomial pathogens.
    Matched MeSH terms: Staphylococcus aureus; Staphylococcus epidermidis
  15. Fulltext First report on the molecular epidemiology of Malaysian Staphylococcus epidermidis isolated from a university teaching hospital
    Sani NA, Sapri HF, Neoh HM, Hussin S
    BMC Res Notes, 2014;7:597.
    PMID: 25186825 DOI: 10.1186/1756-0500-7-597
    Staphylococcus epidermidis is a pathogen associated with nosocomial infections whose medical importance has increased due to progressively invasive medical procedures. In this study, we characterized the molecular epidemiology of S. epidermidis strains circulating in our university hospital situated in Kuala Lumpur, Malaysia.
    Matched MeSH terms: Staphylococcus epidermidis/drug effects; Staphylococcus epidermidis/genetics*; Staphylococcus epidermidis/isolation & purification
  16. Temporal changes in the genotypes of methicillin-resistant Staphylococcus aureus strains isolated from a tertiary Malaysian hospital based on MLST, spa, and mec-associated dru typing
    Lim KT, Hanifah YA, Yusof MY, Goering RV, Thong KL
    Diagn Microbiol Infect Dis, 2012 Oct;74(2):106-12.
    PMID: 22770652 DOI: 10.1016/j.diagmicrobio.2012.05.033
    Methicillin-resistant Staphylococcus aureus (MRSA) is one of the main bacterial pathogens responsible for nosocomial infections leading to pneumonia, bloodstream, skin, and soft tissue infections. The objective of this study was to investigate the genomic changes of MRSA in a tertiary hospital between the years 2003, 2004, 2007, and 2008. One hundred fifty-four MRSA strains were characterized by multilocus sequence typing (MLST), spa, and mec-associated dru typing. Among the 154 strains, 29 different dru, 15 spa, and 8 MLST types were identified. Seven sequence types (STs) (ST239, ST22, ST5, ST6, ST80, ST573, and ST241) were identified among 2007-08 strains, although only 2 STs (ST239 and ST20) were observed among 2003 strains. Clones ST239-t037-dt13g, ST22-t032-(dt10a and dt10aw), and 28 other MRSA clones being introduced in 2007-2008 have replaced the ST239-t037 (dt13d, 14h, 13i, 13l, 13m, 15m, 15l, and 11al) clones present in 2003. The predominant MLST clone, ST239 (90.3%), was further distinguished into 7 different spa types and 26 different dru types, including 17 novel dru types. Maximum parsimony tree based on dru repeats revealed that 10 dru types (dt11am, dt13j, dt15n, dt13q, dt13n, dt13p, dt13f, dt13ao, dt12j, dt7v) shared the same MLST-spa types with dt13d, suggesting that these MRSA clones might have evolved from ST239-t037-dt13d. In conclusion, our data showed that the ST239-t037-dt13d clone and other MRSA clones in 2003 were replaced by ST239-t037-dt13g and other new emerging spa and dru types.
    Matched MeSH terms: Methicillin-Resistant Staphylococcus aureus/classification*; Methicillin-Resistant Staphylococcus aureus/genetics; Methicillin-Resistant Staphylococcus aureus/isolation & purification*
  17. Diversity in the antimicrobial susceptibility patterns of methicillin-resistant Staphylococcus aureus clones
    Ghaznavi-Rad E, Neela V, Nor Shamsudin M, Ghasemzadeh Moghaddam H, Tavakol M, van Belkum A, et al.
    Eur J Clin Microbiol Infect Dis, 2012 Dec;31(12):3317-21.
    PMID: 23010901 DOI: 10.1007/s10096-012-1698-3
    Methicillin-resistant Staphylococcus aureus (MRSA) is well known for its epidemicity, with the emergence of new clones on a daily basis. Diversity in the clonal types of MRSA challenges the success of treatment, as different clones respond to different sets of antibiotics. However, the antibiotic susceptibility among the isolates within the same clones is largely unexplored. In a previous study on MRSA epidemiology in Malaysia, we identified six major clonal complexes (ST-239-CC8, ST-1-CC1, ST-188-CC1, ST-22-CC22, ST-7-CC7 and ST-1283-CC8). In the present study, we investigated the antibiotic susceptibility patterns of isolates of different clones. Three hundred and eighty-nine MRSA isolates were subjected to the disc diffusion test, oxacillin minimum inhibitory concentration (MIC) determination and assessment of the distribution of macrolide, lincosamide and streptogramin B (MLS(B)) resistance genes. Thirty-six different antibiotic profiles were observed: 30 (83.3 %) among ST-239, 2 (5.6 %) among ST-1283 and 1 (2.8 %) each for ST-1, ST-7, ST-22 and ST-188. All ST-239 (362, 9 %) isolates were multiple drug-resistant (MDR; resistant to more than three classes of antibiotics) and had oxacillin MICs >256 mg/l. Among the 385 clindamycin-resistant isolates, 375 (96.4 %) illustrated inducible resistance (D-zone-positive), while 10 (2.6 %) showed constitutive resistance. The vast majority of the macrolide-resistant isolates carried the ermA gene (95.1 %), followed by ermC (12.9 %). Diversity in the antibiotic susceptibilities of isolates within the clones emphasises the need for continuous surveillance of MDR strains to prescribe the correct antibiotic rather than empirical treatment. This will likely reduce the emergence of new endemic or epidemic resistant MRSA clones.
    Matched MeSH terms: Methicillin-Resistant Staphylococcus aureus/classification*; Methicillin-Resistant Staphylococcus aureus/drug effects*; Methicillin-Resistant Staphylococcus aureus/genetics
  18. Fulltext The presence of heterogeneous vancomycin-lntermediate Staphylococcus aureus (heteroVISA) in a major Malaysian hospital
    Norazah A, Law NL, Abd Ghani MK, Salbiah N
    Med J Malaysia, 2012 Jun;67(3):269-73.
    PMID: 23082415
    This study was conducted to detect the presence of heterogenous vancomycin-intermediate Staphylococcus aureus (heteroVISA) among MRSA isolates in a major hospital. Forty-three MRSA isolates with vancomycin MIC 2 microg/ml collected in 2009 was screened for heteroVISA using Etest Glycopeptide Resistance Detection (GRD) and confirmed by population analysis profile-area under curve method. The genetic relatedness of heteroVISA strains with other MRSA was examined by pulsed-field gel electrophoresis (PFGE) method. Two isolates were shown to be heteroVISA and derived from the same clone. This showed that heteroVISA strains were already present among our local strains since 2009 and were genetically related to other susceptible strains.
    Matched MeSH terms: Methicillin-Resistant Staphylococcus aureus/drug effects; Methicillin-Resistant Staphylococcus aureus/genetics; Methicillin-Resistant Staphylococcus aureus/isolation & purification*
  19. Characterization of a diesel-degrading strain isolated from a hydrocarbon-contaminated site
    Shukor MY, Dahalan FA, Jusoh AZ, Muse R, Shamaan NA, Syed MA
    J Environ Biol, 2009 Jan;30(1):145-50.
    PMID: 20112877
    A diesel-degrading bacterium has been isolated from a diesel-polluted site. The isolate was tentatively identified as Staphylococcus aureus strain DRY11 based on partial 16S rDNA molecular phylogeny and Biolog GP microplate panels and Microlog database. Isolate 11 showed an almost linear increase in cellular growth with respect to diesel concentrations with optimum growth occurring at 4% (v/v) diesel concentration. Optimization studies using different nitrogen sources showed that the best nitrogen source was potassium nitrite. Sodium nitrite was optimum at 1.2 g l(-1) and higher concentrations were strongly inhibitory to cellular growth. The optimal pH that supported growth of the bacterium was between 7.5 to 8.0 and the isolate exhibited optimal broad temperature supporting growth on diesel from 27 to 37 degrees C. An almost complete removal of diesel components was seen from the reduction in hydrocarbon peaks observed using Solid Phase Microextraction Gas Chromatography analysis after 5 days of incubation. The characteristics of this bacterium suggest that it is suitable for bioremediation of diesel spills and pollutions in the tropics.
    Matched MeSH terms: Staphylococcus aureus/genetics; Staphylococcus aureus/isolation & purification; Staphylococcus aureus/metabolism*
  20. Fulltext First report on methicillin-resistant Staphylococcus aureus of Spa type T037, Sequence Type 239, SCCmec type III/IIIA in Malaysia
    Neela V, Ghasemzadeh Moghaddam H, van Belkum A, Horst-Kreft D, Mariana NS, Ghaznavi Rad E
    Eur J Clin Microbiol Infect Dis, 2010 Jan;29(1):115-7.
    PMID: 19779745 DOI: 10.1007/s10096-009-0813-6
    Methicillin-resistant Staphylococcus aureus (MRSA) from Malaysia were shown to possess staphylococcal cassette chromosome mec (SCCmec)-III and IIIA. Spa sequencing and multi-locus sequence typing (MLST) documented t037 and ST 239 (CC8) for 83.3% of the isolates. This confirms observations in several other Far Eastern countries and corroborates the epidemicity of this clone.
    Matched MeSH terms: Methicillin-Resistant Staphylococcus aureus/classification*; Methicillin-Resistant Staphylococcus aureus/genetics*; Methicillin-Resistant Staphylococcus aureus/isolation & purification
Related Terms
Filters
Contact Us

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

External Links