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1.
Fotou K Tzora A Voidarou Ch Alexopoulos A Plessas S Avgeris I Bezirtzoglou E Akrida-Demertzi K Demertzis PG 《Anaerobe》2011,17(6):315-319
The natural raw milk microflora is a factor that expresses its sensorial characteristics. The microbial charge into the mammary gland of healthy animal is low and the application of right and healthy conditions during milking and cheese making procedure, prevents from contaminating as well as maintains the natural microflora in order to lend the particular characteristics of milk.The purpose of the present project was the study of the Total Viable Count (T.V.C.) and the count of total psychrotropic bacteria of raw sheep milk from Boutsiko and Karamaniko breeds, collected from healthy animals, as well as the isolation, identification and enumeration of pathogenic bacteria related with the hygiene and the quality of raw sheep milk (with a particular interest in bacteria that may cause human infection).During the experiment we examined two hundred forty (240) samples of raw sheep milk. In these samples a) Staphylococcus aureus, Salmonella sp., Escherichia coli, Clostridium perfringens (vegetative cells and spores) and Bacillus sp. were isolated and identified b) the Total Viable Count and the total number of psychrotropic bacteria were also specified. The sampling, the preparation of samples and decimal dilutions were based on international methods. The Total viable count was determined using the standard methods of the American Public Health Association, 2002. The total number of psychrotropic bacteria was determined using APHA 1976, 1978 rules. The identification of the bacteria was carried out according to the Bergey’s manual. Microscopic examination of Gram stained cells, catalase, oxidase and biochemical tests were performed when necessary to further identify.From the 240 milk samples tested, only 5% were E. coli positive, with mean counts ranged from 2 × 103 to 2.4 × 104 cfu/ml. S. aureus was isolated from 24% of the samples and the mean count per ml was ranged from <10 to 3.4 × 102. Meanwhile, Bacillus spp. was also detected in 29% samples. Vegetative forms and spores of C. perfringens were detected in 13% and 63% of the samples respectively. However, microbiological analyses revealed the presence of a small number of selected pathogens in milk samples such as Salmonella, which was only detected in 5% of the samples. Listeria sp., Pseudomonas sp. and Vibrio cholerae were never found.From the experimental results, the Total Viable Count from raw sheep milk samples, fulfils the microbiological criteria of EU Legislation in a percentage of approximately 97%. 相似文献
2.
Gerokomou V Voidarou C Vatopoulos A Velonakis E Rozos G Alexopoulos A Plessas S Stavropoulou E Bezirtzoglou E Demertzis PG Akrida-Demertzi K 《Anaerobe》2011,17(6):351-353
Ice used for direct human consumption or to preserve foods and cool down drinks can be contaminated with pathogenic microorganisms and may potentially become a vehicle for consumer’s infection. To evaluate physical, chemical and microbiological quality of commercial ice and ice used for fish and seafood, 100 ice samples collected at 10 different retail points in the region of Epirus were studied. The following microbiological parameters were determined: Total coliforms, fecal coliforms, Salmonella spp., Shigella spp., Yersinia spp., Escherichia coli, Campylobacter sp., Vibrio cholerae, Aeromonas spp., Pseudomonas aeruginosa and Clostridium perfringens.E. coli was detected in 22% and coliforms were detected in 31% of samples. Samples in which coliforms were detected fail to meet the microbiological criteria specified by the drinking water legislation.Aeromonas spp., Shigella spp., Campylobacter sp. and V. cholerae were not detected. Spore forms of C. perfringens were prevalent at 35% and the psychotropic bacterium’s P. aeruginosa and Yersinia spp. were found only at three samples each.The presence of large numbers of coliforms as well as of other pathogenic strains suggested that commercial ice and ice used to make cool drinks or in preservation of fish and seafood may represent a potential hazard to the consumer. In view of the results reported herein, it is highly recommended that national regulatory guidelines should be established for the production of ice as long as regular inspections. 相似文献
3.
Summary The heterotrophic bacterial flora of Antarctic fish Notothenia neglecta was studied in Potter Cove (King George Island, South Shetland Islands). Quantitative and qualitative analysis of aerobic bacteria from sea water, skin, stomach and intestine were carried out. In addition, anaerobic flora of stomach and intestine was studied and compared. Pseudomonas was dominant in sea water samples but, neither skin nor digestive tract samples showed to be rich in this genus. Stomach flora showed variable results between samples. The gut flora was composed almost exclusively of Vibrio. Despite extreme environmental conditions this Antarctic fish show an intestinal indigenous microflora very similar to warmer waters fish. Several factors, that we discussed, could be determining the Vibrio dominance in the gut of marine teleosts. 相似文献
4.
Stuffed mussel is a traditional food that sold by street venders in various countries. In the present study, samples of stuffed
mussels were collected from various places in Ankara. The mussels were analyzed to show the microbiological risks for human
health. Thirty samples (600 stuffed mussels in total) were collected periodically and microbiological analyses were performed
by standard procedures for Bacillus cereus, Staphylococcus aureus, Escherichia coli, Salmonella sp., Clostridium sp. In terms of Salmonella sp., approximately 50% of samples were not suitable for consumption. Besides, in accordance with Turkish Food Codex Microbiological
Criteria Announcement in terms of E. coli 30%, in terms of B. cereus 80%, in terms of S. aureus 76.6%, in terms of Clostridium perfringens 13.3% of these samples were not suitable for consumption. The aim of this study is to discuss the microbiological quality
of stuffed mussels as a ready-to-eat food according to Turkish Food Codex (TFC). The result of this investigation indicates
that stuffed mussels as a street food may constitute a potential health hazard, depending on contamination level and lack
of sanitary practices, and therefore, handling practices should require more attention and improvement. 相似文献
5.
【目的】通过研究粪便样本的微生物特点间接探讨猪链球菌2型感染BALB/c小鼠后肠道微生物的变化。【方法】本研究采用IlluminaMiSeq测序技术,测定了健康小鼠和猪链球菌2型感染小鼠粪便中微生物16S rRNA V3-V4区序列,并对群落结构和多样性进行了比较分析。【结果】多样性分析表明,感染组和对照组小鼠的粪便中微生物多样性和群落组成均不相同,存在较大的差异,感染组展示了较高的物种丰度和种群差异性。在门水平上,相对于对照组,感染组增加厚壁菌门和拟杆菌门等有益微生物比例,以提高机体免疫力,但也同时增加了变形杆菌等条件致病菌的比例,增加了疾病发生的可能性。在科水平上,感染组和对照组优势菌均含有瘤胃菌科,但其所占细菌总序列的比例存在较大的差异,分别占感染组和对照组细菌总序列的36.58%和11.02%。在属水平上,感染组和对照组的优势菌属类别及占总微生物比例存在显著的差异。感染组主要以瘤胃菌科UCG-002和乳酸杆菌属为优势菌属,对照组以螺旋体科GWE2-31-10和密螺旋体属2为优势菌属。综上,BALB/c小鼠感染猪链球菌2型后存在肠道微生态失调。【结论】通过本研究,不仅对猪链球菌2... 相似文献
6.
Miller WA Miller MA Gardner IA Atwill ER Byrne BA Jang S Harris M Ames J Jessup D Paradies D Worcester K Melli A Conrad PA 《Microbial ecology》2006,52(2):198-206
The coastal ecosystems of California are highly utilized by humans and animals, but the ecology of fecal bacteria at the land–sea interface is not well understood. This study evaluated the distribution of potentially pathogenic bacteria in invertebrates from linked marine, estuarine, and freshwater ecosystems in central California. A variety of filter-feeding clams, mussels, worms, and crab tissues were selectively cultured for Salmonella spp., Campylobacter spp., Escherichia coli-O157, Clostridium perfringens, Plesiomonas shigelloides, and Vibrio spp. A longitudinal study assessed environmental risk factors for detecting these bacterial species in sentinel mussel batches. Putative risk factors included mussel collection near higher risk areas for livestock or human sewage exposure, adjacent human population density, season, recent precipitation, water temperature, water type, bivalve type, and freshwater outflow exposure. Bacteria detected in invertebrates included Salmonella spp., C. perfringens, P. shigelloides, Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio alginolyticus. Overall, 80% of mussel batches were culture positive for at least one of the bacterial species, although the pathogens Campylobacter, E. coli-O157, and Salmonella were not detected. Many of the same bacterial species were also cultured from upstream estuarine and riverine invertebrates. Exposure to human sewage sources, recent precipitation, and water temperature were significant risk factors for bacterial detection in sentinel mussel batches. These findings are consistent with the hypothesis that filter-feeding invertebrates along the coast concentrate fecal bacteria flowing from land to sea and show that the relationships between anthropogenic effects on coastal ecosystems and the environmental niches of fecal bacteria are complex and dynamic. 相似文献
7.
为了探究从何种类型的自然生境中更易分离得到溶藻微生物,采用高氏1号培养基分别从水库底泥、湖泊底泥、农田土壤、林地土壤等四种来源共36份样品中分离了7 600株菌,并最终从中筛选得到了5株溶铜绿微囊藻(Microcystis aeruginosa)的溶藻菌,其中4株为假单胞菌(Pseudomonas sp.),1株为黄杆菌(Flavobacterium sp.),5株菌溶藻效率的变化范围为62%~95%。结果表明,当采用高氏1号培养基作为分离培养基时,湖泊底泥和水库底泥中的成功筛选概率最高,农田土壤次之,而林地土壤中则难以筛选得到,假单胞菌是较容易筛选得到的溶藻菌。 相似文献
8.
The objective of this study was to determine the effect of two endophytic bacterial elicitors (Pseudomonas sp. and Enterobacter sp.) on the production of alkaloids in protocorm-like bodies (PLBs) of Pinellia ternata Breit. Both bacterial strains increased the growth rate of P. ternata PLBs. Pseudomonas sp. promoted the differentiation of the PLBs, whereas Enterobacter sp. inhibited PLB differentiation. The bacterial strains increased guanosine production in PLBs by 9–166%, inosine production by 2–33%, and trigonelline production by 114–1140% compared to the control. For Pseudomonas sp., guanosine and trigonelline production was greater when bacterial extracts were added to the PLB suspension cultures rather than living cells (co-culture treatment). Inosine production was similar in both the bacterial extract and co-culture treatments. For the Enterobacter sp., guanosine, inosine, and trigonelline production tended to be greatest when living cells were added to the PLB suspension cultures rather than bacterial extracts. These results suggest that Pseudomonas sp. and Enterobacter sp. could increase alkaloid yield from P. ternata under field or tissue culture conditions. We also observed that Pseudomonas sp. and Enterobacter sp. produced some of the same alkaloids as their host plants. Additional study needs to be done to determine if these endophytic bacteria could be used to produce alkaloids in the fermentation industry. 相似文献
9.
Fluorescent Pseudomonas sp. strain 267 promotes growth of nodulated clover plants under gnotobiotic conditions. In the growth conditions (60 M FeCl3), the production of siderophores of the pseudobactin-pyoverdin group was repressed. Plant growth enhancement results from secretion of B vitamins by Pseudomonas sp. strain 267. This was proven by stimulation of clover growth by naturally auxotrophic strains of Rhizobium leguminosarum bv. trifolii and marker strains E. coli thi- and R. meliloti pan- in the presence of the supernatant of Pseudomonas sp. strain 267. The addition of vitamins to the plant medium increased symbiotic nitrogen fixation by the clover plants. 相似文献
10.
The bacterial flora on the heads of four different witloof chicory varieties was examined. The 590 isolates were characterized by their SDS-PAGE protein profiles; they revealed 149 different protein fingerprint types. The fluorescentPseudomonas fingerprint type CH001 was abundantly found on all heads examined. Fourteen other fingerprint types occurred in high densities more than twice. Among these, the following were identified: fluorescentPseudomonas, nonfluorescentPseudomonas sp.,Erwinia herbicola, Erwinia sp., andFlavobacterium sp. The majority of the fingerprint types (90%) was found only once. It was also our objective to isolate bacteria applicable in the biological control of chicory phytopathogens. Isolates of all fingerprint types were tested for in vitro antagonistic activity and for possible deleterious effect on plant growth. FluorescentPseudomonas andSerratia liquefaciens isolates were antagonistic against fungi. Among the 161 fluorescentPseudomonas strains, five were able to produce disease symptoms on chicory leaves upon inoculation. Comparison of the results of this study with those obtained in two previous analyses revealed that the leaf microflora showed some similarities with the bacterial flora of chicory roots. The chicory seed microflora differed from that of both leaves and roots. 相似文献
11.
Background For veterinary management of non‐human primates in captivity, and conservation of wild‐living primates, management of their health risks is necessary. Incidences of pathogenic bacteria in the fecal specimens are considered as one of the useful indicators for non‐invasive health monitoring. Methods We carried out the detection of Clostridium perfringens in feces from captive and wild chimpanzees by the rapid polymerase chain reaction method. Results The bacterium was detected in most fecal specimens (80%) in captive chimpanzees. Contrarily, the detection rate in the wild chimpanzees was low, with 23% (n = 12) of 53 fecal samples from the Bossou group, Guinea, and 1.2% (1/81) in the Mahale group, Tanzania. Conclusions These results show that the intestinal microflora differs between Pan populations under various living conditions, being influenced by their diet and environment. 相似文献
12.
Molecular cloning, expression and characterization of a chitosanase from Microbacterium sp. 总被引:1,自引:0,他引:1
A gene encoding a chitosanase (mschito) was cloned from Microbacterium sp. OU01. The ORF consists of 801 bp which encoded a polypeptide of 266 amino acid residues. The deduced amino acid sequence
shows 98% identity to that of the chitosanase reported in Pseudomonas sp. A-01. In addition, the fusion protein containing MSCHITO was expressed in E. coli and purified using Ni-NTA affinity chromatography. The purified rMSCHITO protein degraded the chitosan (the degree of deacetylation
of 99%) and produced a mixture of chitooligosaccharides. The MSCHITO is thus an endo-chitosanase. 相似文献
13.
An alkali-tolerant cellulase-free xylanase producer, WLI-11, was screened from soil samples collected from a pulp and paper mill in China. It was subsequently identified as a Pseudomonas sp. A mutant, WLUN024, was selected by consecutive mutagenesis by u.v. irradiation and NTG treatment using Pseudomonas sp. WLI-11 as parent strain. Pseudomonas sp. WLUN024 produced xylanase when grown on xylosidic materials, such as hemicellulose, xylan, xylose, and wheat bran. Effects of various nutritional factors on xylanase production by Pseudomonas sp. WLUN024 with wheat bran as the main substrate were investigated. A batch culture of Pseudomonas sp. WLUN024 was conducted under suitable fermentation conditions, where the maximum activity of xylanase reached 1245 U ml−1 after incubating at 37 °C for 24 h. Xylanase produced by Pseudomonas sp. WLUN024 was purified and the molecular weight was estimated as 25.4 kDa. Primary studies on the characteristics of the purified xylanase revealed that this xylanase was alkali-tolerant (optimum pH 7.2–8.0) and cellulase-free. In addition, the xylanase was also capable of producing high quality xylo-oligosaccharides, which indicated its application potential in not only pulp bio-bleaching processes but also in the nutraceutical industry. 相似文献
14.
Ji-Young Kim Youngsoo Kim Kyoung Lee Chi-Kyung Kim 《Biotechnology and Bioprocess Engineering》2001,6(1):56-60
ThepcbC gene encoding (4-chloro-)2,3-dihydroxybiphenyl dioxygenase was cloned from the genomic DNA ofPseudomonas sp. P20 using pKT230 to construct pKK1. A recombinant strain,E. coli KK1, was selected by transforming the pKK1 intoE. coli XL1-Blue. Another recombinant strain,Pseudomonas sp. DJP-120, was obtained by transferring the pKK1 ofE. coli KK1 intoPseudomonas sp. DJ-12 by conjugation. Both recombinant strains showed a 23.7 to 26.5 fold increase in the degradation activity to 2,3-dihydroxybiphenyl
compared with that of the natural isolate,Pseudomonas sp. DJ-12. The DJP-120 strain showed 24.5, 3.5, and 4.8 fold higher degradation activities to 4-chlorobiphenyl, catechol,
and 3-methylcatechol than DJ-12 strain, respectively. The pKK1 plasmid of both strains and their ability to degrade 2,3-dihydroxybiphenyl
were stable even after about 1,200 generations. 相似文献
15.
Cloning and sequencing of the Clostridium perfringens enterotoxin gene 总被引:10,自引:0,他引:10
Marijke van Damme-Jongsten Karel Wernars Servé Notermans 《Antonie van Leeuwenhoek》1989,56(2):181-190
Several gene banks of Clostridium perfringens in E. coli were constructed. Using a mixture of synthetic 29-mer DNA probes clones were selected containing inserts from the C. perfringens gene coding for the enterotoxin. This has allowed sequencing of the complete gene and its flanking regions. The decuded amino acid sequence (320 a.a.) was found to differ at several sites from the sequence published previously by others. Two 40-mer DNA-probes were used to detect the toxin gene in C. perfringens strains isolated from the faeces of different non-symptomatic animals. Only 6% of the strains were found to possess the gene. 相似文献
16.
Polyhydroxyalkanoates (PHAs) are biological polyesters, of which, Short-Chain-Length-Medium-Chain-Length (SCL-MCL) PHA copolymers
are important because of their wide range of applications. The present study focused on molecular characterization of Pseudomonas sp. LDC-5 that is identified as SCL-MCL producer. Phase contrast, fluorescent and electron microscopic observation confirmed
the presence of PHA granules in Pseudomonas sp. LDC-5. PCR analysis indicated the presence of expected amplicon for SCL phaC gene (∼500 bp), MCL phaC1 with phaZ (∼1.3), and phaC2 with phaZ (∼1.5 kb). Sequence analysis of the PHA synthase gene of Pseudomonas sp. LDC-5 revealed significant differences in phaC1 and phaC2 which were further confirmed by recombinant studies. Recombinant Escherichia coli harboring the partial phaC1 gene was able to accumulate PHA, whereas E. coli with phaC2 did not accumulate PHA as verified by fold analysis, immunoblotting, Gas Chromatography (GC), Differential scanning calorimetry
(DSC), and FTIR studies. The predicted theoretical three-dimensional structure revealed that PhaC1 is consistent with α/β hydrolase fold. Monomer
composition showed the presence of monomer ranging from C4 to C12: 1 when glucose and sodium octanoate fed as the carbon source.
DSC revealed melting temperature peak at 153.12°C and glass transition (Tg) peaks at −0.37°C. Thermogravimetric analysis revealed that the polymer was stable up to 276°C. Fourier Transform Infrared
Spectroscopy (FT-IR) spectral analysis showed the PHA specific wave number at 1,739.67 and 1,161.07 cm−1. The potential of Pseudomonas sp. LDC-5 and its properties are discussed. 相似文献
17.
Aderopo Akinsoji 《Plant Ecology》1991,92(2):181-185
Bark microflora of 12 rainforest trees were examined. Crustose, foliose, and fruticose forms of lichens were observed. Bacillus sp., Erwinia sp., Micrococcus sp., Proteus sp., and Pseudomonas sp. were the five genera of bacteria recorded while three genera of Cyanobacteria; Entophysalis, Gleocapsa and Stigonema were observed. In the algal division, three genera of Chlorophyta found are Chlorococcum, Pleurococcus and Physolinum. Only one diatom, Cocconeis sp. was present on just one tree. Most of the epiphytic microflora found are mainly terrestrial and their spores might have been deposited on the barks by air, or dust-currents. While moisture is regarded as the most critical factor in growth of bark microflora, other factors like texture of the bark, insolation and especially chemical characteristics of the barks may play a key role in occurrence and distribution of micro-organisms on them. 相似文献
18.
Yu Yangsheng Bai Gang Liu Chunqin Li Yang Jin Yongjie Yang Wenbo 《Frontiers of Biology in China》2007,2(4):391-396
L-cysteine desulfhydrase (CD) plays an important role in L-cysteine decomposition. To identify the CD gene in Pseudomonas sp. TS1138 and investigate its effect on the L-cysteine biosynthetic pathway, the CD gene was cloned from Pseudomonas sp. TS1138 by polymerase chain reaction (PCR) method. The nucleotide sequence of CD gene was determined to be 1,215 bp, and
its homology with other sequences encoding CD was analyzed. Then the CD gene was subcloned into pET-21a(+) vector and expressed
in Escherichia coli (E. coli) by isopropyl-β-D-thiogalactopyranoside (IPTG) inducement. The recombinant CD was purified by Ni-NTA His-Bind resin, and its activity was
identified by the CD activity staining. The enzymatic properties of the recombinant CD were characterized and its critical
role involved in the L-cysteine biosynthetic pathway was also discussed.
__________
Translated from Microbiology, 2006, 33(4): 21–26 [译自: 微生物学通报] 相似文献
19.
Molecular characterization based on 16s rDNA gene sequence analysis of bacterial colonies isolated from endosulfan contaminated
soil showed the presence of Ochrobacterum sp, Burkholderia sp, Pseudomonas alcaligenes, Pseudomonas sp and Arthrobacter sp which degraded 57–90% of α-endosulfan and 74–94% of β-endosulfan after 7days. Whole cells of Pseudomonas sp and Pseudomonas alcaligenes showed 94 and 89% uptake of α-isomer and 86 and 89% of β-endosulfan respectively in 120 min. In Pseudomonas sp, endosulfan sulfate was the major metabolite detected during the degradation of α-isomer, with minor amount of endosulfan
diol while in Pseudomonas alcaligenes endosulfan diol was the only product during α-endosulfan degradation. Whole cells of Pseudomonas sp also utilized 83% of endosulfan sulfate in 120 min. In situ applications of the defined consortium consisting of Pseudomonas alcaligenes and Pseudomonas sp (1:1) in plots contaminated with endosulfan showed that 80% of α-endosulfan and 65% of β-endosulfan was degraded after
12 weeks of incubation. Endosulfan sulfate formed during endosulfan degradation was subsequently degraded to unknown metabolites.
ERIC-PCR analysis indicated 80% survival of introduced population of Pseudomonas alcaligenes and Pseudomonas sp in treated plots. 相似文献
20.
《Bioscience, biotechnology, and biochemistry》2013,77(8):1798-1800
The catechol 2,3-dioxygenase (C23O) gene in naphthalene catabolic plasmid pND6-1 of Pseudomonas sp. ND6 was cloned and sequenced. The C23O gene was consisted of 924 nucleotides and encoded a polypeptide of molecular weight 36 kDa containing 307 amino acid residues. The C23O of Pseudomonas sp. ND6 exhibited 93% and 89% identities in amino acid sequence with C23Os encoded by naphthalene catabolic plasmid NAH7 from Pseudomonas putida G7 and the chromosome of Pseudomonas stutzeri AN10 respectively. The Pseudomonas sp. ND6 C23O gene was overexpressed in Escherichia coli DH 5α using the lac promoter of pUC18, and its gene product was purified by DEAE-Sephacel and Phenyl-Sepharose CL-4B chromatography. The enzymology experiments indicated that the specific activity and thermostability of C23O from Pseudomonas sp. ND6 were better than those of C23O from Pseudomonas putida G7. 相似文献