Displaying publications 1 - 20 of 2525 in total

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  1. [The first monkey malaria in Turkey: a case of Plasmodium knowlesi]
    Özbilgin A, Çavuş İ, Yıldırım A, Gündüz C
    Mikrobiyol Bul, 2016 Jul;50(3):484-90.
    PMID: 27525405
    Plasmodium knowlesi is now added to the known four Plasmodium species (P.vivax, P.falciparum, P.malariae, P.ovale) as a cause of malaria in humans because of the recent increasing rate of cases reported from countries of southeastern Asia. P.knowlesi which infects macaque monkeys (Macaca fascicularis and M.nemestrina) is transmitted to humans especially by Anopheles leucosphyrus and An.hackeri mosquitos. First human cases of P.knowlesi malaria have been detected in Malaysia which have reached high numbers in recent years and also have been reported from countries of Southeast Asia such as Thailand, Philippines, Myanmar, Singapore and Vietnam. However the number of cases reported from western countries are rare and limited only within voyagers. This report is the first presentation of an imported case of P.knowlesi malaria in Turkey and aims to draw attention to the point that it could also be detected in future. A 33-year-old male patient from Myanmar who has migrated to Turkey as a refugee, was admitted to a health center with the complaints of fever with a periodicity of 24 hours, headache, fatigue, cough, sore throat, anorexia, myalgia and arthralgia. He was prediagnosed as upper respiratory tract infection, however because of his periodical fever and background in Myanmar, thick and thin blood films were prepared and sent to our laboratory for further examinations. Microscopic examination of the thin blood films revealed erythrocytic stages compatible with P.knowlesi (three large early trophozoites in an erythrocyte, three late trophozoites with compact view, and three late band-form trophozoites). Upon this, both real-time polymerase chain reaction (Rt-PCR) targeting the small subunit ribosomal RNA (SSU-rRNA) genes of Plasmodium genus and DNA sequence analysis targeting P.knowlesi rRNA gene were performed. As a result, the suspected identification of P.knowlesi by microscopy was confirmed by Rt-PCR and DNA sequencing. The patient was treated with chloroquine and primaquine combination and in the follow-up on the seventh day after the treatment, his parasitemia and symptoms had ceased. Although there were some previous reports concerning about imported patients infected with different Plasmodium species in our country, no cases of P.knowlesi have been reported. This first case presented here emphasizes the occurence of P.knowlesi malaria in Turkey hereinafter due to the increasing number of refugees.
    Matched MeSH terms: Anopheles/classification; Mosquito Vectors/classification
  2. Fulltext The evolutionary history of extinct and living lions
    de Manuel M, Barnett R, Sandoval-Velasco M, Yamaguchi N, Garrett Vieira F, Zepeda Mendoza ML, et al.
    Proc Natl Acad Sci U S A, 2020 May 19;117(20):10927-10934.
    PMID: 32366643 DOI: 10.1073/pnas.1919423117
    Lions are one of the world's most iconic megafauna, yet little is known about their temporal and spatial demographic history and population differentiation. We analyzed a genomic dataset of 20 specimens: two ca. 30,000-y-old cave lions (Panthera leo spelaea), 12 historic lions (Panthera leo leo/Panthera leo melanochaita) that lived between the 15th and 20th centuries outside the current geographic distribution of lions, and 6 present-day lions from Africa and India. We found that cave and modern lions shared an ancestor ca. 500,000 y ago and that the 2 lineages likely did not hybridize following their divergence. Within modern lions, we found 2 main lineages that diverged ca. 70,000 y ago, with clear evidence of subsequent gene flow. Our data also reveal a nearly complete absence of genetic diversity within Indian lions, probably due to well-documented extremely low effective population sizes in the recent past. Our results contribute toward the understanding of the evolutionary history of lions and complement conservation efforts to protect the diversity of this vulnerable species.
    Matched MeSH terms: Lions/classification
  3. [Clostridium bifermentans serovar malaysia, a new anaerobic bacterium pathogen to mosquito and blackfly larvae]
    de Barjac H, Sebald M, Charles JF, Cheong WH, Lee HL
    C. R. Acad. Sci. III, Sci. Vie, 1990;310(9):383-7.
    PMID: 1972899
    A strain of Clostridium bifermentans individualized as serovar malaysia (C.b.m.) according to its specific H antigen is toxic to mosquito and blackfly larvae when given orally. The toxicity occurs in sporulated cells which contain, in addition to spores, proteinic parasporal inclusion bodies and feather-like appendages; the amino acid content of the inclusion bodies is similar to that of Bacillus thuringiensis serovar israelensis (B.t.i.) and B. sphaericus crystals. The toxicity to Anopheles stephensi is as high as that of B.t.i. and the best strains of B. sphaericus. Culex pipiens is somewhat less susceptible, and Aedes aegypti much less. Pure parasporal inclusion bodies, isolated by ultracentrifugation on sucrose gradients, are highly toxic to mosquito larvae. The larvicidal power is destroyed by heating at 80 degrees C or by treatment with 50 mM NaOH. It is preserved by freeze-drying. The innocuity to mice of the sporulated cells is shown by different routes of administration: force-feeding, percutaneous, subcutaneous, intraperitoneal or intravenous injections. The potential for the biological control of mosquito and blackfly larvae is suggested.
    Matched MeSH terms: Clostridium/classification
  4. [A possible fifth dengue virus serotype]
    da Silva Voorham JM
    Ned Tijdschr Geneeskd, 2014;158:A7946.
    PMID: 25227888
    Sylvatic dengue viruses are both evolutionarily and ecologically distinguishable from the human dengue virus (DENV). Sporadic episodes of sylvatic human infections in West Africa and Southeast Asia suggest that sylvatic DENV regularly come into contact with human beings. Following a study on the sylvatic transmission cycle in Malaysia in 2007, researchers announced that a new DENV serotype, DENV-5, had been discovered. Scientists are still sceptical about these new findings, and indicate that more data is necessary to determine whether this 'new' virus really is a different serotype or whether it is a variant of one of the four DENV serotypes already known. The good news is that this new variant has not yet established itself in the human transmission cycle. However, if it really is a new serotype this will have implications for the long-term control of dengue using vaccines currently under development.
    Matched MeSH terms: Dengue Virus/classification*
  5. Fulltext In vitro differentiation between oxytocin- and vasopressin-secreting magnocellular neurons requires more than one experimental criterion
    da Silva MP, Merino RM, Mecawi AS, Moraes DJ, Varanda WA
    Mol Cell Endocrinol, 2015 Jan 15;400:102-11.
    PMID: 25451978 DOI: 10.1016/j.mce.2014.11.004
    The phenotypic differentiation between oxytocin (OT)- and vasopressin (VP)-secreting magnocellular neurosecretory cells (MNCs) from the supraoptic nucleus is relevant to understanding how several physiological and pharmacological challenges affect their electrical activity. Although the firing patterns of OT and VP neurons, both in vivo and in vitro, may appear different from each other, much is assumed about their characteristics. These assumptions make it practically impossible to obtain a confident phenotypic differentiation based exclusively on the firing patterns. The presence of a sustained outward rectifying potassium current (SOR) and/or an inward rectifying hyperpolarization-activated current (IR), which are presumably present in OT neurons and absent in VP neurons, has been used to distinguish between the two types of MNCs in the past. In this study, we aimed to analyze the accuracy of the phenotypic discrimination of MNCs based on the presence of rectifying currents using comparisons with the molecular phenotype of the cells, as determined by single-cell RT-qPCR and immunohistochemistry. Our results demonstrated that the phenotypes classified according to the electrophysiological protocol in brain slices do not match their molecular counterparts because vasopressinergic and intermediate neurons also exhibit both outward and inward rectifying currents. In addition, we also show that MNCs can change the relative proportion of each cell phenotype when the system is challenged by chronic hypertonicity (70% water restriction for 7 days). We conclude that for in vitro preparations, the combination of mRNA detection and immunohistochemistry seems to be preferable when trying to characterize a single MNC phenotype.
    Matched MeSH terms: Neurons/classification
  6. Fulltext A bibliometric analysis of research productivity of Malaysian publications in leading toxicology journals during a 10-year period (2003-2012)
    Zyoud Sh, Al-Jabi S, Sweileh W, Awang R
    Hum Exp Toxicol, 2014 Dec;33(12):1284-93.
    PMID: 24505047 DOI: 10.1177/0960327113514101
    Toxicology in Malaysia has experienced rapid development and made great progress in education and research in conjunction with economic development in Malaysia over the past two decades.
    Matched MeSH terms: Periodicals as Topic/classification
  7. Cheсklist of gastropod molluscs in mangroves of Khanh Hoa province, Vietnam
    Zvonareva S, Kantor Y
    Zootaxa, 2016 Sep 12;4162(3):401-37.
    PMID: 27615983 DOI: 10.11646/zootaxa.4162.3.1
    Gastropod molluscs are one of the most important components of mangrove ecosystem. Mangroves in Central Vietnam have a rather limited distribution due to peculiarities of the coastline morphology and presently their fauna remains understudied. Extensive surveys were conducted in both natural vegetation and artificial mangrove plantations in several localities in Nha Trang Bay from 2005 to 2015. In total 65 species of gastropod molluscs were found alive, 17 of which can be considered as predominantly mangrove-associated. An illustrated guide is provided, with short synonymies and data on ecology and distribution. The recorded molluscan diversity is compared with published data on mangrove gastropods in different regions of the Indo-Pacific. Total species number and the proportion of mangrove-associated species are similar to studied faunas in Hong Kong, Malaysia and Thailand, but the diversity is much lower than that of the mangal fauna of the Philippines.
    Matched MeSH terms: Gastropoda/classification*
  8. Circulating human group A rotavirus genotypes in Malaysia
    Zuridah H, Kirkwood CD, Bogdanovic-Sakran N, Bishop RF, Yap KL
    J Med Virol, 2010 Apr;82(4):707-11.
    PMID: 20166178 DOI: 10.1002/jmv.21717
    This study examined the temporal distribution of rotavirus genotypes in Malaysia. Rotaviruses from children with diarrhea admitted to hospitals in 1996 (n = 93) and 2007 (n = 12) in two different regions of Peninsular (West) Malaysia were analyzed for their G and P genotypes using a hemi-nested RT-PCR assay. In the 2007 samples, the dominant strain was G9P[8]. It was identified in 42% of the samples. Different strains all possessing the G1 genotype were identified in the rest of the samples. In contrast, 81% of the samples collected in 1996 were the G1P[8] strain. No strains with G9 genotype were detected in samples collected in 1996.
    Matched MeSH terms: Rotavirus/classification*
  9. Sequence and phylogenetic analysis of S1, S2, M, and N genes of infectious bronchitis virus isolates from Malaysia
    Zulperi ZM, Omar AR, Arshad SS
    Virus Genes, 2009 Jun;38(3):383-91.
    PMID: 19242786 DOI: 10.1007/s11262-009-0337-2
    Two Malaysian infectious bronchitis virus isolates, MH5365/95 and V9/04 were characterized based on sequence and phylogenetic analyses of S1, S2, M, and N genes. Nucleotide sequence alignments revealed many point mutations, short deletions, and insertions in S1 region of both IBV isolates. Phylogenetic analysis of S1 gene and sequences analysis of M gene indicated that MH5365/95 and V9/04 belong to non-Massachusetts strain. However, both isolates share only 77% identity. Analysis based on S1 gene showed that MH5365/95 shared more than 87% identity to several Chinese strains. Meanwhile, V9/04 showed only 67-77% identity to all the previously studied IBV strains included in this study suggesting it is a variant of IBV isolate that is unique to Malaysia. Phylogenetic analysis suggests, although both isolates were isolated 10 years apart from different states in Malaysia, they shared a common origin. Analysis based on S2 and N genes indicated that both strains are highly related to each other, and there are fewer mutations which occurred in the respective genes.
    Matched MeSH terms: Infectious bronchitis virus/classification*
  10. Fulltext The epiphytic microbiota of the globally widespread macroalga Cladophora glomerata (Chlorophyta, Cladophorales)
    Zulkifly S, Hanshew A, Young EB, Lee P, Graham ME, Graham ME, et al.
    Am J Bot, 2012 Sep;99(9):1541-52.
    PMID: 22947483 DOI: 10.3732/ajb.1200161
    The filamentous chlorophyte Cladophora produces abundant nearshore populations in marine and freshwaters worldwide, often dominating periphyton communities and producing nuisance growths under eutrophic conditions. High surface area and environmental persistence foster such high functional and taxonomic diversity of epiphytic microfauna and microalgae that Cladophora has been labeled an ecological engineer. We tested the hypotheses that (1) Cladophora supports a structurally and functionally diverse epiphytic prokaryotic microbiota that influences materials cycling and (2) mutualistic host-microbe interactions occur. Because previous molecular sequencing-based analyses of the microbiota of C. glomerata found as western Lake Michigan beach drift had identified pathogenic associates such as Escherichia coli, we also asked if actively growing lentic C. glomerata harbors known pathogens.
    Matched MeSH terms: Bacteria/classification
  11. Phenotypic and genetic characterization of multidrug-resistant Staphylococcus aureus in the tropics of Southeast Asia
    Zulkeflle SNM, Yusaimi YA, Sugiura N, Iwamoto K, Goto M, Utsumi M, et al.
    Microbiology (Reading), 2016 12;162(12):2064-2074.
    PMID: 27902427 DOI: 10.1099/mic.0.000392
    Antibiotic resistance has become a major public health problem throughout the world. The presence of antibiotic-resistant bacteria such as Staphylococcus aureus and antibiotic resistance genes (ARGs) in hospital wastewater is a cause for great concern today. In this study, 276 Staph. aureus isolates were recovered from hospital wastewater samples in Malaysia. All of the isolates were screened for susceptibility to nine different classes of antibiotics: ampicillin, ciprofloxacin, gentamicin, kanamycin, erythromycin, vancomycin, trimethoprim and sulfamethoxazole, chloramphenicol, tetracycline and nalidixic acid. Screening tests showed that 100 % of Staph.aureus isolates exhibited resistance against kanamycin, vancomycin, trimethoprim and sulfamethoxazole and nalidixic acid. Additionally, 91, 87, 50, 43, 11 and 8.7 % of isolates showed resistance against erythromycin, gentamicin, ciprofloxacin, ampicillin, chloramphenicol and tetracycline, respectively. Based on these results, 100 % of isolates demonstrated multidrug-resistant (MDR) characteristics, displaying resistance against more than three classes of antibiotics. Of 276 isolates, nine exhibited resistance to more than nine classes of tested antibiotics; these were selected for antibiotic susceptibility testing and examined for the presence of conserved ARGs. Interestingly, a high percentage of the selected MDR Staph.aureus isolates did not contain conserved ARGs. These results indicate that non-conserved MDR gene elements may have already spread into the environment in the tropics of Southeast Asia, and unique resistance mechanisms against several antibiotics may have evolved due to stable, moderate temperatures that support growth of bacteria throughout the year.
    Matched MeSH terms: Staphylococcus aureus/classification
  12. Fulltext Multiple species of scuttle flies (Diptera: Phoridae) as contaminants in forensic entomology laboratory insect colony
    Zuha RM, Jenarthanan LX, Disney RH, Omar B
    Trop Biomed, 2015 Sep;32(3):568-72.
    PMID: 26695221 MyJurnal
    In forensic entomology, larval rearing usually includes the presence of biological contaminants including scuttle flies (Diptera: Phoridae). Scuttle flies are recognized as forensically important insects and have been reported causing nuisance and contamination in laboratory environments. This paper reports for the first time the finding of multiple scuttle fly species affecting colonies of third instar larvae of the Oriental latrine blowfly, Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae), reared indoors at the Forensic Science Simulation Site, Universiti Kebangsaan Malaysia. Adult scuttle flies were discovered inside a rearing container after the emergence of adult C. megacephala., The scuttle fly species are Megaselia scalaris (Loew), M. spiracularis Schmitz and Puliciphora borinquenensis (Wheeler). Notes on the life history and biology of these species are discussed herein.
    Matched MeSH terms: Diptera/classification*
  13. Fulltext Fly artifact documentation of Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae) - a forensically important blowfly species in Malaysia
    Zuha RM, Supriyani M, Omar B
    Trop Biomed, 2008 Apr;25(1):17-22.
    PMID: 18600200
    Analysis on fly artifacts produced by forensically important blowfly, Chrysomya megacephala (Fabricius) (Diptera:Calliphoridae), revealed several unique patterns. They can be divided into fecal spots, regurgitation spots and swiping stains. The characteristics of fecal spots are round with three distinct levels of pigmentation; creamy, brownish and darkly pigmented. Matrix of the spots appears cloudy. The round spots are symmetrical and non-symmetrical, delineated by irregular and darker perimeter which only visible in fairly colored fecal spots. Diameter of these artifacts ranged from 0.5 mm to 4 mm. Vomit or regurgitation spots are determined by the presence of craters due to sucking activity of blowflies and surrounded by thickly raised and darker colored perimeter. The size of these specks ranged from 1 mm to 2 mm. Matrix of the spots displays irregular surface and reflective under auxiliary microscope light. Swiping stains due to defecation by flies consists of two distinguishable segments, the body and tail. It can be seen as a tear drop-like, sperm-like, snake-like and irregular tadpole-like stain. The direction of body and tail is inconsistent and length ranged between 4.8 mm to 9.2 mm. A finding that should be highlighted in this observation is the presence of crater on tadpole-like swiping stain which is apparent by its raised border characteristic and reflective under auxiliary microscope light. The directionality of this darkly brown stain is random. This unique mix of regurgitation and swiping stain has never been reported before. Highlighting the features of artifacts produced by flies would hopefully add our understanding in differentiating them from blood spatters produced from victims at crime scenes.
    Matched MeSH terms: Diptera/classification*
  14. Fulltext Multilocus sequence types of clinical Burkholderia pseudomallei isolates from peninsular Malaysia and their associations with disease outcomes
    Zueter AR, Rahman ZA, Abumarzouq M, Harun A
    BMC Infect Dis, 2018 01 02;18(1):5.
    PMID: 29291714 DOI: 10.1186/s12879-017-2912-9
    BACKGROUND: Previous studies on the Burkholderia pseudomallei genetic diversity among clinical isolates from melioidosis-endemic areas have identified genetic factors contributing to differential virulence. Although it has been ruled out in Australian and Thai B. pseudomallei populations, it remains unclear whether B. pseudomallei sequence types (STs) correlate with disease in Malaysian patients with melioidosis.

    METHODS: In this study, multi-locus sequence typing (MLST) was performed on clinical B. pseudomallei isolates collected from Kelantan state of Malaysia, patients' clinical data were reviewed and then genotype-risk correlations were investigated.

    RESULTS: Genotyping of 83 B. pseudomallei isolates revealed 32 different STs, of which 13(40%) were novel. The frequencies of the STs among the 83 isolates ranged from 1 to 12 observations, and ST54, ST371 and ST289 were predominant. All non-novel STs reported in this study have also been identified in other Asian countries. Based on the MLST data analysis, the phylogenetic tree showed clustering of the STs with each other, as well as with the STs from Southeast Asia and China. No evidence for associations between any of B. pseudomallei STs and clinical melioidosis presentation was detected. In addition, the bacterial genotype clusters in relation with each clinical outcome were statistically insignificant, and no risk estimate was reported. This study has expanded the data for B. pseudomallei on MLST database map and provided insights into the molecular epidemiology of melioidosis in Peninsular Malaysia.

    CONCLUSION: This study concurs with previous reports concluding that infecting strain type plays no role in determining disease presentation.

    Matched MeSH terms: Burkholderia pseudomallei/classification
  15. Amycolatopsis thermophila sp. nov. and Amycolatopsis viridis sp. nov., thermophilic actinomycetes isolated from arid soil
    Zucchi TD, Tan GYA, Goodfellow M
    Int J Syst Evol Microbiol, 2012 Jan;62(Pt 1):168-172.
    PMID: 21378137 DOI: 10.1099/ijs.0.029256-0
    The taxonomic positions of two thermophilic actinomycetes isolated from an arid Australian soil sample were established based on an investigation using a polyphasic taxonomic approach. The organisms had chemical and morphological properties typical of members of the genus Amycolatopsis and formed distinct phyletic lines in the Amycolatopsis methanolica 16S rRNA subclade. The two organisms were distinguished from one another and from the type strains of related species of the genus Amycolatopsis using a range of phenotypic properties. Based on the combined genotypic and phenotypic data, it is proposed that the two isolates be classified in the genus Amycolatopsis as Amycolatopsis thermophila sp. nov. (type strain GY088(T)=NCIMB 14699(T)=NRRL B-24836(T)) and Amycolatopsis viridis sp. nov. (type strain GY115(T)=NCIMB 14700(T)=NRRL B-24837(T)).
    Matched MeSH terms: Actinomycetales/classification*
  16. Amycolatopsis granulosa sp. nov., Amycolatopsis ruanii sp. nov. and Amycolatopsis thermalba sp. nov., thermophilic actinomycetes isolated from arid soils
    Zucchi TD, Tan GYA, Bonda ANV, Frank S, Kshetrimayum JD, Goodfellow M
    Int J Syst Evol Microbiol, 2012 Jun;62(Pt 6):1245-1251.
    PMID: 21764982 DOI: 10.1099/ijs.0.031039-0
    The taxonomic positions of three thermophilic actinomycetes isolated from arid soil samples were established by using a polyphasic approach. The organisms had chemical and morphological features that were consistent with their classification in the genus Amycolatopsis. 16S rRNA gene sequence data supported the classification of the isolates in the genus Amycolatopsis and showed that they formed distinct branches in the Amycolatopsis methanolica subclade. DNA-DNA relatedness studies between the isolates and their phylogenetic neighbours showed that they belonged to distinct genomic species. The three isolates were readily distinguished from one another and from the type strains of species classified in the A. methanolica subclade based on a combination of phenotypic properties and by genomic fingerprinting. Consequently, it is proposed that the three isolates be classified in the genus Amycolatopsis as representatives of Amycolatopsis granulosa sp. nov. (type strain GY307(T) = NCIMB 14709(T) = NRRL B-24844(T)), Amycolatopsis ruanii sp. nov. (type strain NMG112(T) = NCIMB 14711(T) = NRRL B-24848(T)) and Amycolatopsis thermalba sp. nov. (type strain SF45(T) = NCIMB 14705(T) = NRRL B-24845(T)).
    Matched MeSH terms: Actinomycetales/classification*
  17. Dentoalveolar relationships of Malay children with unilateral cleft lip and palate
    Zreaqat M, Hassan R, Halim AS
    Cleft Palate Craniofac J, 2009 May;46(3):326-30.
    PMID: 19642750 DOI: 10.1597/07-210.1
    To determine the treatment outcome based on dentoalveolar relationships among Malay children born with nonsyndromic complete unilateral cleft lip and palate (UCLP).
    Matched MeSH terms: Malocclusion/classification*
  18. Fulltext An imported case of acute melioidosis caused by ST881 Burkholderia pseudomallei
    Zong Z, Wang X, Deng Y
    Southeast Asian J. Trop. Med. Public Health, 2016 Mar;47(2):219-22.
    PMID: 27244959
    A previously healthy Chinese male working in Malaysia returned to China with high fever. A blood culture showed Burkholderia pseudomallei strain WCBP1. This isolate was sequenced, showing type, ST881, which appears to be present in Malaysia. WCP1 had unusual susceptibility to aminoglycosides and habored the Yersinia-like fimbrial gene cluster for virulence. The patient's condition deteriorated rapidly but he recovered after receiving meropenem and intensive care support. Melioidosis is a potential problem among Chinese imigrant workers with strains new to China being identified.
    Matched MeSH terms: Burkholderia pseudomallei/classification
  19. Misidentification of Burkholderia pseudomallei as Burkholderia cepacia by the VITEK 2 system
    Zong Z, Wang X, Deng Y, Zhou T
    J Med Microbiol, 2012 Oct;61(Pt 10):1483-1484.
    PMID: 22820689 DOI: 10.1099/jmm.0.041525-0
    A previously healthy Chinese male returned from working in the Malaysian jungle with a fever. A blood culture grew Gram-negative bacilli that were initially identified as Burkholderia cepacia by the VITEK 2 system but were subsequently found to be Burkholderia pseudomallei by partial sequencing of the 16S rRNA gene. The identification of B. pseudomallei using commercially available automated systems is problematic and clinicians in non-endemic areas should be aware of the possibility of melioidosis in patients with a relevant travel history and blood cultures growing Burkholderia spp.
    Matched MeSH terms: DNA, Bacterial/classification; RNA, Bacterial/classification; RNA, Ribosomal, 16S/classification; Burkholderia cepacia/classification*; Burkholderia pseudomallei/classification*
  20. Fulltext Selection and identification of non-pathogenic bacteria isolated from fermented pickles with antagonistic properties against two shrimp pathogens
    Zokaeifar H, Balcázar JL, Kamarudin MS, Sijam K, Arshad A, Saad CR
    J Antibiot (Tokyo), 2012 Jun;65(6):289-94.
    PMID: 22491136 DOI: 10.1038/ja.2012.17
    In this study, potential probiotic strains were isolated from fermented pickles based on antagonistic activity against two shrimp pathogens (Vibrio harveyi and Vibrio parahaemolyticus). Two strains L10 and G1 were identified by biochemical tests, followed by16S ribosomal RNA gene sequence analysis as Bacillus subtilis, and characterized by PCR amplification of repetitive bacterial DNA elements (Rep-PCR). Subsequently, B. subtilis L10 and G1 strains were tested for antibacterial activity under different physical conditions, including culture medium, salinity, pH and temperature using the agar well diffusion assay. Among the different culture media, LB broth was the most suitable medium for antibacterial production. Both strains showed the highest level of antibacterial activity against two pathogens at 30 °C and 1.0% NaCl. Under the pH conditions, strain G1 showed the greatest activity against V. harveyi at pH 7.3-8.0 and against V. parahaemolyticus at pH 6.0-8.0, whereas strain L10 showed the greatest activity against two pathogens at pH 7.3. The cell-free supernatants of both strains were treated with four different enzymes in order to characterize the antibacterial substances against V. harveyi. The result showed considerable reduction of antibacterial activity for both strains, indicating the proteinaceous nature of the antibacterial substances. A wide range of tolerance to NaCl, pH and temperature was also recorded for both strains. In addition, both strains showed no virulence effect in juvenile shrimp Litopenaeus vannamei. On the basis of these results and safety of strains to L. vannamei, they may be considered for future challenge experiments in shrimp as a very promising alternative to the use of antibiotics.
    Matched MeSH terms: Bacillus subtilis/classification*; Probiotics/classification*
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