Displaying publications 1 - 20 of 892 in total

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  1. Spruijtenburg B, Ahmad S, Asadzadeh M, Alfouzan W, Al-Obaid I, Mokaddas E, et al.
    Mycoses, 2023 Dec;66(12):1079-1086.
    PMID: 37712885 DOI: 10.1111/myc.13655
    Candida auris is an emerging, multidrug-resistant yeast, causing outbreaks in healthcare facilities. Echinocandins are the antifungal drugs of choice to treat candidiasis, as they cause few side effects and resistance is rarely found. Previously, immunocompromised patients from Kuwait with C. auris colonisation or infection were treated with echinocandins, and within days to months, resistance was reported in urine isolates. To determine whether the development of echinocandin resistance was due to independent introductions of resistant strains or resulted from intra-patient resistance development, whole genome sequencing (WGS) single-nucleotide polymorphism (SNP) analysis was performed on susceptible (n = 26) and echinocandin-resistant (n = 6) isolates from seven patients. WGS SNP analysis identified three distinct clusters differing 17-127 SNPs from two patients, and the remaining isolates from five patients, respectively. Sequential isolates within patients had a maximum of 11 SNP differences over a time period of 1-10 months. The majority of isolates with reduced susceptibility displayed unique FKS1 substitutions including a novel FKS1M690V substitution, and nearly all were genetically related, ranging from only three to six SNP differences compared to susceptible isolates from the same patient. Resistant isolates from three patients shared the common FKS1S639F substitution; however, WGS analysis did not suggest a common source. These findings strongly indicate that echinocandin resistance is induced during antifungal treatment. Future studies should determine whether such echinocandin-resistant strains are capable of long-term colonisation, cause subsequent breakthrough candidiasis, have a propensity to cross-infect other patients, or remain viable for longer time periods in the hospital environment.
    Matched MeSH terms: Microbial Sensitivity Tests
  2. Aziman N, Abdullah N, Noor ZM, Kamarudin WS, Zulkifli KS
    J Food Sci, 2014 Apr;79(4):M583-92.
    PMID: 24666004 DOI: 10.1111/1750-3841.12419
    Preliminary phytochemical and flavonoid compounds of aqueous and ethanolic extracts of 6 aromatic Malaysian herbs were screened and quantified using Reverse-Phase High Performance Liquid Chromatography (RP-HPLC). The herbal extracts were tested for their antimicrobial activity against 10 food-borne pathogenic and food spoilage microorganisms using disk diffusion assay. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC)/minimum fungicidal concentration (MFC) of herbal extracts were determined. In the phytochemical screening process, both aqueous and ethanolic extracts of P. hydropiper exhibited presence of all 7 tested phytochemical compounds. Among all herbal extracts, the aqueous P. hydropiper and E. elatior extracts demonstrated the highest antibacterial activity against 7 tested Gram-positive and Gram-negative bacteria with diameter ranging from 7.0 to 18.5 mm and 6.5 to 19 mm, respectively. The MIC values for aqueous and ethanolic extracts ranged from 18.75 to 175 mg/mL and 0.391 to 200 mg/mL, respectively while the MBC/MFC values for aqueous and ethanolic extracts ranged from 25 to 200 mg/mL and 3.125 to 50 mg/mL, respectively. Major types of bioactive compounds in aqueous P. hydropiper and E. elatior extracts were identified using RP-HPLC instrument. Flavonoids found in these plants were epi-catechin, quercetin, and kaempferol. The ability of aqueous Persicaria hydropiper (L.) H. Gross and Etlingera elatior (Jack) R.M. Sm. extracts to inhibit the growth of bacteria is an indication of its broad spectrum antimicrobial potential. Hence these herbal extracts may be used as natural preservative to improve the safety and shelf-life of food and pharmaceutical products.
    Matched MeSH terms: Microbial Sensitivity Tests
  3. Ahmad R, Baharum SN, Bunawan H, Lee M, Mohd Noor N, Rohani ER, et al.
    Molecules, 2014 Nov 20;19(11):19220-42.
    PMID: 25420073 DOI: 10.3390/molecules191119220
    The aim of this research was to identify the volatile metabolites produced in different organs (leaves, stem and roots) of Polygonum minus, an important essential oil producing crop in Malaysia. Two methods of extraction have been applied: Solid Phase Microextraction (SPME) and hydrodistillation coupled with Gas Chromatography-Mass Spectrometry (GC-MS). Approximately, 77 metabolites have been identified and aliphatic compounds contribute significantly towards the aroma and flavour of this plant. Two main aliphatic compounds: decanal and dodecanal were found to be the major contributor. Terpenoid metabolites were identified abundantly in leaves but not in the stem and root of this plant. Further studies on antioxidant, total phenolic content, anticholinesterase and antimicrobial activities were determined in the essential oil and five different extracts. The plant showed the highest DPPH radical scavenging activity in polar (ethanol) extract for all the tissues tested. For anti-acetylcholinesterase activity, leaf in aqueous extract and methanol extract showed the best acetylcholinesterase inhibitory activities. However, in microbial activity, the non-polar extracts (n-hexane) showed high antimicrobial activity against Methicillin-resistant Staphylococcus aureus (MRSA) compared to polar extracts. This study could provide the first step in the phytochemical profiles of volatile compounds and explore the additional value of pharmacology properties of this essential oil producing crop Polygonum minus.
    Matched MeSH terms: Microbial Sensitivity Tests/methods
  4. Sarwar A, Katas H, Samsudin SN, Zin NM
    PLoS One, 2015;10(4):e0123084.
    PMID: 25928293 DOI: 10.1371/journal.pone.0123084
    Recently, the attention of researchers has been drawn toward the synthesis of chitosan derivatives and their nanoparticles with enhanced antimicrobial activities. In this study, chitosan derivatives with different azides and alkyne groups were synthesized using click chemistry, and these were further transformed into nanoparticles by using the ionotropic gelation method. A series of chitosan derivatives was successfully synthesized by regioselective modification of chitosan via an azide-alkyne click reaction. The amino moieties of chitosan were protected during derivatization by pthaloylation and subsequently unblocked at the end to restore their functionality. Nanoparticles of synthesized derivatives were fabricated by ionic gelation to form complexes of polyanionic penta-sodium tripolyphosphate (TPP) and cationic chitosan derivatives. Particle size analysis showed that nanoparticle size ranged from 181.03 ± 12.73 nm to 236.50 ± 14.32 nm and had narrow polydispersity index and positive surface charge. The derivatives and corresponding nanoparticles were evaluated in vitro for antibacterial and antifungal activities against three gram-positive and gram-negative bacteria and three fungal strains, respectively. The minimum inhibitory concentration (MIC) of all derivatives ranged from 31.3 to 250 µg/mL for bacteria and 188 to1500 µg/mL for fungi and was lower than that of native chitosan. The nanoparticles with MIC ranging from 1.56 to 25 µg/mLfor bacteria and 94 to 750 µg/mL for fungi exhibited higher activity than the chitosan derivatives. Chitosan O-(1-methylbenzene) triazolyl carbamate and chitosan O-(1-methyl phenyl sulfide) triazolyl carbamate were the most active against the tested bacterial and fungal strains. The hemolytic assay on erythrocytes and cell viability test on two different cell lines (Chinese hamster lung fibroblast cells V79 and Human hepatic cell line WRL68) demonstrated the safety; suggesting that these derivatives could be used in future medical applications. Chitosan derivatives with triazole functionality, synthesized by Huisgen 1,3-dipolar cycloaddition, and their nanoparticles showed significant enhancement in antibacterial and antifungal activities in comparison to those associated with native, non-altered chitosan.
    Matched MeSH terms: Microbial Sensitivity Tests
  5. Basri DF, Tan LS, Shafiei Z, Zin NM
    PMID: 22203875 DOI: 10.1155/2012/632796
    The galls of Quercus infectoria are commonly used in Malay traditional medicine to treat wound infections after childbirth. In India, they are employed traditionally as dental applications such as that in treatment of toothache and gingivitis. The aim of the present study was to evaluate the antibacterial activity of galls of Quercus infectoria Olivier against oral bacteria which are known to cause dental caries and periodontitis. Methanol and acetone extracts were screened against two Gram-positive bacteria (Streptococcus mutans ATCC 25175 and Streptococcus salivarius ATCC 13419) and two Gram-negative bacteria (Porphyromonas gingivalis ATCC 33277 and Fusobacterium nucleatum ATCC 25586). The screening test of antibacterial activity was performed using agar-well diffusion method. Subsequently, minimum inhibitory concentration (MIC) was determined by using twofold serial microdilution method at a concentration ranging between 0.01 mg/mL and 5 mg/mL. Minimum bactericidal concentration (MBC) was obtained by subculturing microtiter wells which showed no changes in colour of the indicator after incubation. Both extracts showed inhibition zones which did not differ significantly (P < 0.05) against each tested bacteria. Among all tested bacteria, S. salivarius was the most susceptible. The MIC ranges for methanol and acetone extracts were the same, between 0.16 and 0.63 mg/mL. The MBC value, for methanol and acetone extracts, was in the ranges 0.31-1.25 mg/mL and 0.31-2.50 mg/mL, respectively. Both extracts of Q. infectoria galls exhibited similar antibacterial activity against oral pathogens. Thus, the galls may be considered as effective phytotherapeutic agents for the prevention of oral pathogens.
    Matched MeSH terms: Microbial Sensitivity Tests
  6. 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: Microbial Sensitivity Tests
  7. Yu L, Lu M, Zhang W, Alarfaj AA, Hirad AH, Zhang H
    Microb Pathog, 2020 Apr;141:103960.
    PMID: 31953224 DOI: 10.1016/j.micpath.2019.103960
    BACKGROUND: Mycoplasma pneumoniae (MP) is a common cause of community-acquired pneumonia (CAP) among the children and adults that results upper and lower respiratory tract infections.

    OBJECTIVE: This study was aimed to inspect the ameliorative action of A. chinensis synthesized ZnONPs against M. pneumoniae infected pneumonia mice model.

    MATERIALS AND METHODS: ZnO NPs was synthesized from Albizia chinensis bark extract and characterized by UV-Vis spectroscopy, Fourier Transform Infrared (FTIR), Transmission Electron Microscopy (TEM), energy dispersive X-ray (EDX) and atomic force microscope (AFM) analyses. The antibacterial effectual of synthesized ZnONPs were examined against clinical pathogens. The pneumonia was induced to BALB/c mice via injecting the M. pneumoniae and treated with synthesized ZnONPs, followed by the total protein content, total cell counts and inflammatory mediators level was assessed in the BALF of experimental animals. The Histopathological investigation was done in the lung tissues of test animals.

    RESULTS: The outcomes of this work revealed that the formulated ZnONPs was quasi-spherical, radial and cylindrical; the size was identified as 116.5 ± 27.45 nm in diameter. The in vitro antimicrobial potential of formulated ZnO-NPs displayed noticeable inhibitory capacity against the tested fungal and bacterial strains. The administration of synthesized ZnO-NPs in MP infected mice model has significantly reduced the levels of total protein, inflammatory cells, inflammatory cytokines such as IL-1, IL-6, IL-8, tumour necrosis factor-alpha (TNF-a) and transforming growth factor (TGF). Besides, the histopathological examination of MP infected mice lung tissue showed the cellular arrangements were effectively retained after administration of synthesized ZnO-NPs.

    CONCLUSION: In conclusion, synthesized ZnO-NPs alleviate pneumonia progression via reducing the level of inflammatory cytokines and inflammatory cells in MP infected mice model.

    Matched MeSH terms: Microbial Sensitivity Tests
  8. Puvan Arul Arumugam, Irfan Mohamad, Rosdan Salim, Zeehaida Mohamed
    MyJurnal
    Azadirachta indica (neem) has been used for a long time in agricultural and alternative medicine. Neem
    had been proved effective against certain fungi that could infect human body. This pilot study aims to
    demonstrate the antifungal effect of Malaysian neem leaf extracts on the pathogenic fungi in otomycosis,
    Aspergillus niger and Candida albicans. This is a laboratory-controlled prospective study conducted at
    Universiti Sains Malaysia. The powder form of Malaysian neem leaf was prepared. Ethanol and aqueous
    extracts of the neem leaf was diluted with sterile water to establish five different concentrations of 50 g/
    ml, 25 g/ml, 12.5 g/ml, 6.25 g/ml and 3.125g/ml. The extract was tested on Sabouraud Dextrose Agar
    suspended with Candida albicans and Aspergillus niger respectively. Well diffusion method was used
    and zone of inhibition was measured. Growth of the fungi was inhibited in both alcohol and aqueous
    extract concentrations. The minimum inhibitory concentration (MIC) of Malaysian neem aqueous extract
    against Candida albicans was 11.91 g/ml, neem ethanol extract against Candida albicans was 5.16 g/
    ml, neem aqueous extract against Aspergillus niger was 7.73 g/ml and neem ethanol extract against
    Aspergillus niger was 9.25 g/ml. Statistical analysis showed that the antifungal activity of Candida
    albicans is better in alcohol neem than aqueous extract (p
    Matched MeSH terms: Microbial Sensitivity Tests
  9. Gorajana A, Venkatesan M, Vinjamuri S, Kurada BV, Peela S, Jangam P, et al.
    Microbiol Res, 2007;162(4):322-7.
    PMID: 16580188
    In our systematic screening programme for marine actinomycetes, a bioactive Streptomycete was isolated from marine sediment samples of Bay of Bengal, India. The taxonomic studies indicated that the isolate belongs to Streptomyces chibaensis and it was designated as S. chibaensis AUBN1/7. The isolate yielded a cytotoxic compound. It was obtained by solvent extraction followed by the chromatographic purification. Based on the spectral data of the pure compound, it was identified as quinone-related antibiotic, resistoflavine (1). It showed a potent cytotoxic activity against cell lines viz. HMO2 (Gastric adenocarcinoma) and HePG2 (Hepatic carcinoma) in vitro and also exhibited weak antibacterial activities against Gram-positive and Gram-negative bacteria.
    Matched MeSH terms: Microbial Sensitivity Tests
  10. Goh TC, Bajuri MY, C Nadarajah S, Abdul Rashid AH, Baharuddin S, Zamri KS
    J Foot Ankle Res, 2020 Jun 16;13(1):36.
    PMID: 32546270 DOI: 10.1186/s13047-020-00406-y
    BACKGROUND: Diabetic foot infection is a worldwide health problem is commonly encountered in daily practice. This study was conducted to identify the microbiological profile and antibiotic sensitivity patterns of causative agents identified from diabetic foot infections (DFIs). In addition, the assessment included probable risk factors contributing to infection of ulcers that harbour multidrug-resistant organisms (MDROs) and their outcomes.

    METHODS: We carried out a prospective analysis based on the DFI samples collected from 2016 till 2018. Specimens were cultured with optimal techniques in addition to antibiotic susceptibility based on recommendations from The Clinical and Laboratory Standards Institute (CLSI). A total of 1040 pathogens were isolated with an average of 1.9 pathogens per lesion in 550 patients who were identified with having DFIs during this interval.

    RESULTS: A higher percentage of Gram-negative pathogens (54%) were identified as compared with Gram-positive pathogens (33%) or anaerobes (12%). A total of 85% of the patients were found to have polymicrobial infections. Pseudomonas aeruginosa (19%), Staphylococcus aureus (11%) and Bacteroides species (8%) appeared to be the predominant organisms isolated. In the management of Gram-positive bacteria, the most efficacious treatment was seen with the use of Vancomycin, while Imipenem and Amikacin proved to be effective in the treatment of Gram-negative bacteria.

    CONCLUSION: DFI's are common among Malaysians with diabetes, with a majority of cases displaying polymicrobial aetiology with multi-drug resistant isolates. The data obtained from this study will be valuable in aiding future empirical treatment guidelines in the treatment of DFIs. This study investigated the microbiology of DFIs and their resistance to antibiotics in patients with DFIs that were managed at a Tertiary Care Centre in Malaysia.

    Matched MeSH terms: Microbial Sensitivity Tests
  11. Mat Zawawi NZ, Shaari R, Luqman Nordin M, Hayati Hamdan R, Peng TL, Zalati CWSCW
    Vet World, 2020 Mar;13(3):508-514.
    PMID: 32367957 DOI: 10.14202/vetworld.2020.508-514
    Background and Aim: Channa striatus extract, a freshwater snakehead fish known as Haruan, is popular in Southeast Asia for consumption and as a traditional therapeutic remedy for wound healing. C. striatus is also used in osteoarthritic for its anti-inflammatory. The aim of this study was to determine the presence of antibacterial properties of C. striatus extract against oral bacteria and to investigate the cytotoxic activity against Vero cells.

    Materials and Methods: The authors prepared C. striatus extract in chloroform-methanol solvents. Next, the authors took subgingival microbiological samples from 16 cats that had periodontal disease. The authors determined the antibacterial properties of C. striatus extract against the isolated bacteria using the disk diffusion method and a broth microdilution-based resazurin microtiter assay. Finally, the authors used the Vero cell line to evaluate the cytotoxic activity, and they assessed the cell availability using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.

    Results: The results showed weak antibacterial activity of C. striatus extract against Pseudomonas spp. and Escherichia coli. In addition, the authors found that minimum inhibition concentration values ranged between 400 and 500 mg/mL, and minimum bactericidal concentration values ranged between 650 and 550 mg/mL. However, the cytotoxic results were promising, showing that C. striatus extract increased the cell viability and growth when it was at a higher concentration. The extract also promotes growth and cell proliferation.

    Conclusion: These findings suggest that C. striatus extract promoted cell proliferation in vitro and could be a plausible therapeutic wound healing alternative for periodontal disease in cats.

    Matched MeSH terms: Microbial Sensitivity Tests
  12. Malahubban M, Alimon AR, Sazili AQ, Fakurazi S, Zakry FA
    Trop Biomed, 2013 Sep;30(3):467-80.
    PMID: 24189677 MyJurnal
    Leaves of Andrographis paniculata and Orthosiphon stamineus were extracted with water, ethanol, methanol and chloroform to assess their potential as antibacterial and antioxidant agents. High performance liquid chromatography analysis showed that the methanolic extracts of A. paniculata and O. stamineus leaves gave the highest amounts of andrographolide and rosmarinic acid, respectively. These leaf extracts exhibited antimicrobial and antioxidant activities and, at the highest concentration tested (200 mg/mL), showed greater inhibitory effects against the Gram positive bacteria Bacillus cereus and Staphylococcus aureus than 10% acetic acid. Andrographis paniculata and O. stamineus methanolic and ethanolic leaf extracts also showed the strongest antioxidant activity as compared with the other extracts tested. The bioactive compounds present in these leaf extracts have the potential to be developed into natural antibacterial and antioxidant agents that may have applications in animal and human health.
    Matched MeSH terms: Microbial Sensitivity Tests
  13. Noorizhab Fakhruzzaman MN, Abidin NZ, Aziz ZA, Lim WF, Richard JJ, Noorliza MN, et al.
    Int J Mycobacteriol, 2019 12 4;8(4):320-328.
    PMID: 31793500 DOI: 10.4103/ijmy.ijmy_144_19
    Background: Tuberculosis (TB) is still a major health problem in Malaysia with thousands of cases reported yearly. This is further burdened with the emergence of multidrug-resistant TB (MDR-TB). Whole-genome sequencing (WGS) provides high-resolution molecular epidemiological data for the accurate determination of Mycobacterium tuberculosis complex (MTBC) lineages and prediction of the drug-resistance patterns. This study aimed to investigate the diversity of MTBC in Malaysia in terms of lineage and drug-resistance patterns of the clinical MTBC isolates using WGS approach.

    Methods: The genomes of 24 MTBC isolated from sputum and pus samples were sequenced. The phenotypic drug susceptibility testing (DST) of the isolates was determined for ten anti-TB drugs. Bioinformatic analysis comprising genome assembly and annotation and single-nucleotide polymorphism (SNP) analysis in genes associated with resistance to the ten anti-TB drugs were done on each sequenced genome.

    Results: The draft assemblies covered an average of 97% of the expected genome size. Eleven isolates were aligned to the Indo-Oceanic lineage, eight were East-Asian lineage, three were East African-Indian lineage, and one was of Euro-American and Bovis lineages, respectively. Twelve of the 24 MTBC isolates were phenotypically MDR M. tuberculosis: one is polyresistance and another one is monoresistance. Twenty-six SNPs across nine genes associated with resistance toward ten anti-TB drugs were detected where some of the mutations were found in isolates that were previously reported as pan-susceptible using DST. A haplotype consisting of 65 variants was also found among the MTBC isolates with drug-resistance traits.

    Conclusions: This study is the first effort done in Malaysia to utilize 24 genomes of the local clinical MTBC isolates. The high-resolution molecular epidemiological data obtained provide valuable insights into the mechanistic and epidemiological qualities of TB within the vicinity of Southeast Asia.

    Matched MeSH terms: Microbial Sensitivity Tests
  14. Hara H, Yusaimi YA, Zulkeflle SNM, Sugiura N, Iwamoto K, Goto M, et al.
    J Gen Appl Microbiol, 2019 Jan 24;64(6):284-292.
    PMID: 29877296 DOI: 10.2323/jgam.2018.02.003
    The emergence of antibiotic resistance among multidrug-resistant (MDR) microbes is of growing concern, and threatens public health globally. A total of 129 Escherichia coli isolates were recovered from lowland aqueous environments near hospitals and medical service centers in the vicinity of Kuala Lumpur, Malaysia. Among the eleven antibacterial agents tested, the isolates were highly resistant to trimethoprim-sulfamethoxazole (83.7%) and nalidixic acid (71.3%) and moderately resistant to ampicillin and chloramphenicol (66.7%), tetracycline (65.1%), fosfomycin (57.4%), cefotaxime (57.4%), and ciprofloxacin (57.4%), while low resistance levels were found with aminoglycosides (kanamycin, 22.5%; gentamicin, 21.7%). The presence of relevant resistance determinants was evaluated, and the genotypic resistance determinants were as follows: sulfonamides (sulI, sulII, and sulIII), trimethoprim (dfrA1 and dfrA5), quinolones (qnrS), β-lactams (ampC and blaCTX-M), chloramphenicol (cmlA1 and cat2), tetracycline (tetA and tetM), fosfomycin (fosA and fosA3), and aminoglycosides (aphA1 and aacC2). Our data suggest that multidrug-resistant E. coli strains are ubiquitous in the aquatic systems of tropical countries and indicate that hospital wastewater may contribute to this phenomenon.
    Matched MeSH terms: Microbial Sensitivity Tests
  15. Supardy NA, Ibrahim D, Sulaiman SF, Zakaria NA
    J Microbiol Biotechnol, 2012 Jun;22(6):872-81.
    PMID: 22573167
    The inhibitory effect of the Klebsiella pneumoniae ATCC 13883 strain caused by the hexane extract of Halimeda discoidea (Nor Afifah et al., 2010) was further evaluated by means of the microscopy view and its growth curves. The morphological changes of the K. pneumoniae ATCC 13883 cells were observed under the scanning electron microscope (SEM) and transmission electron microscope (TEM) after they were treated at minimum inhibitory concentration (MIC; 0.50 mg/ml) (Nor Afifah et al., 2010) for 12, 24, and 36 h. The results showed the severity of the morphological deteriorations experienced by the treated cells. The killing curve assay was performed for 48 h at three different extract concentrations (1/2 MIC, MIC, and 2 MIC). An increase in the extract concentration of up to 2 MIC value did significantly reduce the number of cells by approximately 1.9 log10, as compared with the control. Identification of the potential compounds of the extract responsible for the antibacterial activity was carried out through the gas chromatography-mass spectrum (GCMS) analysis of the active subfraction, and the compound E-15-heptadecenal was identified and suggested as the most potential antibacterial compound of this extract. The subsequent cellular degenerations showed by the data might well explain the inhibitory mechanisms of the suggested antibacterial compound. All of these inhibitory effects have further proven the presence of an antibacterial compound within H. discoidea that can inhibit the growth of K. pneumoniae ATCC 13883.
    Matched MeSH terms: Microbial Sensitivity Tests
  16. Purwasena IA, Fitri DK, Putri DM, Endro H, Zakaria MN
    J Dent, 2024 May;144:104961.
    PMID: 38527516 DOI: 10.1016/j.jdent.2024.104961
    OBJECTIVES: Lipopeptide Biosurfactant (LB) is a bacteria derived compound able to reduce surface tension between water and hydrophobic substances and exhibit antimicrobial and anti-biofilm properties. This study aimed to investigate the antimicrobial and anti-biofilm effect of a Lipopeptide Biosurfactant (LB) on Enterococcus faecalis, and its potential use in root canal treatment, either as a standalone irrigation solution or in conjunction with sodium hypochlorite (NaOCl).

    METHODS: LB was extracted from Bacillus clausii isolate and the dry extract was diluted in deionized water. The antimicrobial effect of LB against planktonic E. faecalis was evaluated by determining the Minimal Inhibitory Concentration (MIC50). The anti-biofilm effect was evaluated by Minimal Biofilm Inhibitory Concentration (MBIC50) and Minimal Biofilm Eradication Concentration (MBEC50) assays on biofilm grown on dentin specimen surface. To evaluate the effectiveness of LB as a single irrigation solution and as a pre-irrigation prior to NaOCl, live and dead bacterial cells were quantified using Confocal Laser Scanning Microscopy (CLSM), and cell biomass was assessed.

    RESULTS: LB exhibited an MIC50 and MBIC50 of 100 ppm, with an MBEC50 of 1000 ppm, resulting in 52.94 % biofilm inhibition and 60.95 % biofilm eradication on dentin specimens. The effectiveness was concentration-dependent, at 500 ppm, LB demonstrated comparable antimicrobial efficacy to 2.5 % NaOCl. Pre-irrigation with LB resulted in lower biofilm biomass compared to NaOCl alone.

    CONCLUSION: Pre-irrigation with LB enhanced the antimicrobial effect when followed by NaOCl irrigation. Consequently, LB shows promise as both a standalone root canal irrigation solution and as an adjunct to NaOCl in root canal treatment.

    CLINICAL SIGNIFICANCE: The study highlights the potential of Lipopeptide Biosurfactant (LB) as an environmentally friendly irrigation solution for root canal treatment, demonstrating potent antimicrobial and anti-biofilm properties against Enterococcus faecalis. LB exhibits concentration-dependent efficacy comparable to 2.5 % NaOCl and can be used as a standalone irrigation solution or in conjunction with NaOCl.

    Matched MeSH terms: Microbial Sensitivity Tests*
  17. Ramaiya SD, Bujang JS, Zakaria MH
    ScientificWorldJournal, 2014;2014:167309.
    PMID: 25028673 DOI: 10.1155/2014/167309
    This study focused on total phenolic content (TPC) and antioxidant and antibacterial activities of the leaves and stems of Passiflora quadrangularis, P. maliformis, and P. edulis extracted using three solvents: petroleum ether, acetone, and methanol. The maximum extraction yields of antioxidant components from the leaves and stems were isolated using methanol extracts of P. edulis (24.28%) and P. quadrangularis (9.76%), respectively. Among the leaf extracts, the methanol extract of P. maliformis had the significantly highest TPC and the strongest antioxidant activity, whereas among the stem extracts, the methanol extract of P. quadrangularis showed the highest phenolic amount and possessed the strongest antioxidant activity. The antibacterial properties of the Passiflora species were tested using the disc diffusion method against 10 human pathogenic bacteria. The largest inhibition zone was observed for the methanol extract of P. maliformis against B. subtilis. Generally, extracts from the Passiflora species exhibit distinct inhibition against Gram-positive but not Gram-negative bacteria. Based on the generated biplot, three clusters of bacteria were designated according to their performance towards the tested extracts. The present study revealed that methanol extracts of the Passiflora contain constituents with significant phenolic, antioxidant, and antibacterial properties for pharmaceutical and nutraceutical uses.
    Matched MeSH terms: Microbial Sensitivity Tests
  18. Yenn TW, Lee CC, Ibrahim D, Zakaria L
    J Microbiol, 2012 Aug;50(4):581-5.
    PMID: 22923105 DOI: 10.1007/s12275-012-2083-8
    This study examined the effect of host extract in the culture medium on anti-candidal activity of Phomopsis sp. ED2, previously isolated from the medicinal herb Orthosiphon stamineus Benth. Interestingly, upon addition of aqueous host extract to the culture medium, the ethyl acetate extract prepared from fermentative broth exhibited moderate anti-candidal activity in a disc diffusion assay. The minimal inhibitory concentration of this extract was 62.5 μg/ml and it only exhibited fungistatic activity against C. albicans. In the time-kill study, a 50% growth reduction of C. albicans was observed at 31.4 h for extract from the culture incorporating host extract. In the bioautography assay, only one single spot (Rf 0.59) developed from the extract exhibited anti-candidal activity. A spot with the a similar Rf was not detected for the crude extract from YES broth without host extract. This indicated that the terpenoid anti-candidal compound was only produced when the host extract was introduced into the medium. The study concluded that the incorporation of aqueous extract of the host plant into the culture medium significantly enhanced the anti-candidal activity of Phomopsis sp. ED2.
    Matched MeSH terms: Microbial Sensitivity Tests
  19. Rohani MY, Raudzah A, Lau MG, Zaidatul AA, Salbiah MN, Keah KC, et al.
    Int J Antimicrob Agents, 2000 Jan;13(3):209-13.
    PMID: 10724026
    Isolates of 390 Staphylococcus aureus were tested against 13 different antibiotics by a disc diffusion method as recommended by the National Committee for Clinical Laboratory Standards (NCCLS). Strains were isolated from blood (5.7%), cerebrospinal fluid (0.5%), respiratory tract (11.8%), pus and wound (73.3%), urine (1.8%), genital specimens (1.0%) and other specimens (4.3%). Only 4.6% of the isolates were fully susceptible to all the drugs tested. Resistance to penicillin was 94.1%, methicillin, 39.7%, chloramphenicol, 8.5%, ciprofloxacin, 29.2%, clindamycin, 2.1%, erythromycin, 45.9% gentamicin, 40.5%; rifampicin, 3.3% tetracycline, 47.2%, co-trimoxazole, 38.5%, mupirocin, 2.8%, fusidic acid, 3.6%. None of the isolates was resistant to vancomycin. The susceptibility of methicillin-resistant strains to erythromycin, gentamicin, tetracycline and ciprofloxacin was low, while clindamycin, fusidic acid, mupirocin, and rifampicin remained active.
    Matched MeSH terms: Microbial Sensitivity Tests
  20. Woh PY, Thong KL, Behnke JM, Lewis JW, Zain SNM
    J Food Prot, 2017 Aug;80(8):1378-1383.
    PMID: 28722485 DOI: 10.4315/0362-028X.JFP-16-342
    Asymptomatic Salmonella carriers who work as food handlers pose food safety and public health risks, particularly during food preparation, and this has serious implications for the disease burden in society. Therefore, we conducted a study to determine the number of Salmonella carriers in a migrant cohort in several food establishments in three major cities in Peninsular Malaysia. Sociodemographic data and stool samples were collected and analyzed using standard methods of detection and isolation. Antimicrobial susceptibility tests of the positive samples were also performed. A total of 317 migrant food handlers, originating from South and Southeast Asian countries, were recruited voluntarily. Nine (2.8%) stool samples were confirmed to be Salmonella positive. PCR serotyping and pulsed-field gel electrophoresis identified four serotypes as Typhimurium (n = 3), Corvallis (n = 2), Hadar (n = 1), Agona (n = 1) and two unknown serovars. Antimicrobial susceptibility tests revealed that all nine isolates were susceptible to amoxicillin-clavulanic acid, cefotaxime, ceftazidime, ceftriaxone, and gentamycin. However, seven isolates were found to be multidrug resistant to ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, sulfonamides, streptomycin, and tetracycline. This study highlights that carriers of nontyphoidal Salmonella exist among migrant food handlers, which poses a health risk to consumers through food contamination. Our results indicate a need for authorities to enhance food safety awareness in the migrant workers and to reevaluate current health screening methods to include preventive measure such as mandatory stool screening as part of the preemployment and routine health examinations.
    Matched MeSH terms: Microbial Sensitivity Tests
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