API Kit Research Articles

Production of violet pigment by a newly isolated psychrotrophic bacterium from a glacier in Xinjiang, China

A psychrotrophic XT1 strain (CGMCC 1194) isolated from a glacier in China's Xinjiang province produced violet pigments at a high content. This strain was identified as Janthinobacterium lividum XT1 by API kit and 16S rDNA analysis. The main fraction of violet pigment was violacein based on the analysis by HPLC-MS and 1 H NMR. The pigment production by J. lividum XT1 was not associated with the cell growth, and a cultivation temperature lower than 20 °C was required for the cell growth and pigment production. Sucrose was the most suitable carbon source, and casein was the best nitrogen source for cell growth and pigment formation. Mineral components in the medium, including CaNO 3 , FeSO 4 , riboflavin, MgSO 4 and nicotinic acid, showed different effects on the cell growth and pigment production. The maximum pigment productivity reached 0.8 g pigment per dry cell weight. The pigment production pattern by our isolate was different from that by other strains such as J. lividum reported so far.

Physiological characterization of starch-utilizing Saccharomyces sp. SK0704 isolated from kimchi

Saccharomyces sp. SK0704 (further defined as SK0704) isolated from long-term-ripening kimchi was identified by a biochemical method with an API kit; its physiology was found to be very similar to that of S. cerevisiae ATCC 26603 (further defined as ATCC 26603), except in terms of starch utilization. SK0704 did not excrete extracellular glucoamylase, but utilized starch as a sole carbon source under only aerobic conditions. Crude enzyme excreted from SK0704 catalyzed the saccharification of starch to glucose, but ATCC 26603 did not. The PCR product obtained using the chromosomal DNA of SK0704 and the primers designed on the basis of the extracellular glucoamylase-coding gene of S. diastaticus was homologous with the intracellular sporulation-specific glucoamylase of S. cerevisiae. SDS-PAGE pattern of soluble protein extracted from yeast cells grown on glucose was greatly different from that on starch. From these results, we proposed that the SK0704 may have a specific physiological function for starch catabolism such as membrane transport system and intracellular sac-charification of starch.

Enhanced Rapidity for Qualitative Detection of Listeria monocytogenes Using an Enzyme-Linked Immunosorbent Assay and Immunochromatography Strip Test Combined with Immunomagnetic Bead Separation

An enzyme-linked immunosorbent assay (ELISA), immunochromatography (ICG) strip test, and immunomagnetic bead separation (IMBS) system based on a monoclonal antibody were individually developed for the detection and isolation of Listeria monocytogenes in meat samples. The three methods showed a strong reaction with Listeria species and a weak reaction with Staphylococcus aureus. To increase the rapidity of L. monocytogenes detection, combinations of the ELISA and ICG strip test with the IMBS system (ELISA-IMBS and ICG-IMBS) were investigated. In comparative analyses of artificially inoculated meat and samples of processed meat, the ELISA and ICG strip test required 24 h of enrichment time to detect the inoculated meat samples with ≥ 1 × 102 CFU/10 g, whereas the ELISA-IMBS and ICG-IMBS required only 14 h of enrichment. Analyses of naturally contaminated meat samples (30 pork samples, 20 beef samples, 26 chicken samples, 20 fish samples, and 20 processed meat samples) performed by ELISA-IMBS, ICG-IMBS, and API kit produced similar results. The ELISA-IMBS and ICG-IMBS provide a more rapid assay than the individual ELISA and the ICG strip test and are appropriate for rapid and qualitative detection of L. monocytogenes (or Listeria species) in meat samples. With the ICG-IMBS, L. monocytogenes could be detected in meat samples within 15 h and the method has potential as a rapid, cost-effective on-site screening tool for the detection of L. monocytogenes in food samples and agricultural products at a minimum detection level of ~100 CFU/10 g.

김치로부터 분리한 Lactobacillus plantarum JK-01의 동정 및 생리적 특성

김치의 L. plantarum의 생균제적 특성을 조사하기 위하여 김치에서 산생산과 성장능력 등이 우수한 25종의 Lactobacillus sp.를 분리하였고, API kit 분석에 의하여 L. plantarum을 동정하고 재차 16S rDNA 염기서열(99.9% 상동성)을 비교한 후 L. plantarum JK-01로 표기하였다. L. plantarum JK-01은 MRS broth에서 배양시 18시간 후 <TEX>$2.9{\times}10^{10}CFU/ml$</TEX>로 최대로 증식하는 빠른 성장특성을 나타냈으며 pH도 4.5로 조속히 하강하였다. 효소활성은 xylanase, amylase, protease, phytase의 순으로 높은 활성을 포함하고 있는 것으로 예측되었다. L. plantarum JK-01은 pH 2에서도 <TEX>$1.36{\times}10^5CFU/mL$</TEX>가 생존하였고, 1%의 담즙산에서도 약 <TEX>$10^6CFU/mL$</TEX>이상이 생존하여 내산성과 내담즙산성이 강한 것으로 나타났다. 또, <TEX>$60^{\circ}C$</TEX>에서도 <TEX>$3.3{\times}10^3$</TEX> CFU/mL 정도로 생존하는 내열성이 있었으며, 대장균과 함께 배양시 18시간 후 대장균을 사멸시키는 것으로 나타났다. 이상의 결과로부터 분리한 L. plantarum JK-01은 생균제로서 충분히 이용가치가 있는 것으로 사료되었다. In order to identify probiotic microorganisms, 25 isolates of Lactobacillus sp. were selected from kimchi based on their growth rates, lactic acid production and salt tolerance. The isolate JK-01 was identified as Lactobacillus plantarum by the API kit and 16S rDNA analysis (99.9% of homology), and named as L. plantarum JK-01. The maximum number of L. plantarum JK-01 was reached at 18 hr fermentation in MRS broth and the pH gradually decreased to 4.5. L. plantarum JK-01 showed high enzyme activities for xylanase, amylase, protease, and phytase on MRS agar plates containing each substrate. L. plantarum JK-01 showed high resistance to acidic pH and bile salts, and grew well even at pH 2.0 and 1.0% bile salt. In particular, L. plantarum JK-01 showed high heat stability as shown by <TEX>$3.3{\times}10^3$</TEX> CFU/mL at <TEX>$60^{\circ}C$</TEX>. The isolate showed remarkable antimicrobial activity against E. coli in MRS broth based on its disappearance after 18 hr and clear zone formation using a paper disk assay. These results suggest that L. plantarum JK-01 may be probiotic in nature.

Uniting creative applications and asset management systems: New opportunities for developers and DAM vendors

With the proliferation of different media and publishing platforms, the need for DAM systems has never been stronger. Digital assets are an increasingly invaluable part of an organization's intellectual property, yet deploying DAM systems across multiple workgroups and promoting active, productive use of systems is an ongoing challenge. With the release of Adobe Creative Suite 3, Adobe has raised the bar on integration among its desktop creative software applications. What is somewhat less obvious to DAM vendors and developers is that the company has also boosted integration capabilities and opportunities for the content and asset management world. Adobe introduced the Version Cue CS3 open API and software development kit (SDK). These tools enable developers to integrate DAM and publishing systems with Adobe Creative Suite 3 applications. The result is that developers and DAM providers can create custom asset management and workflow solutions that help enterprises simplify their processes and increase productivity across multiple workgroups — all while allowing creative professionals to stay within their desktop applications.

The comparison of tonsillar surface and core cultures in recurrent tonsillitis

Objective This study was conducted to investigate whether there is any difference between tonsillar surface and deep tissue cultures in patients who underwent tonsillectomy for recurrent tonsillitis. Methods Tonsillar surface and core tonsillar cultures were taken in all patients. The samples were inoculated into 5% sheep blood, chocolate, and MacConkey agar. The bacteria isolated were identified by using standard methods as well as API kits (Bio Mérieux) if necessary. Results Pathogenic bacteria were isolated in 77 patients, and no pathogenic bacteria were recovered in 39 of 116 patients included in the study. Of these 77 patients, in 52 patients, different types of bacteria were recovered from the surface and deep tissue cultures, whereas in 25 patients, the same types of bacteria were isolated from both surface and deep tissue cultures. The estimated probabilities of tonsillar bacteriology via surface swabs for Haemophilus influenzae, Staphylococcus aureus, Streptococcus pneumoniae, and group A β-hemolytic streptococci were 27.2%, 38.4% , 66.6%. and 62.5%, respectively. H influenzae was less frequently predicted by surface culture than others. Conclusions We think that the swab cultures taken from the tonsillar surface may not always reveal the real pathogen of the tonsils. In addition, the estimated probability of tonsillar bacteriology by surface swabs varies with the type of the pathogen. If medical therapy is planned on the basis of the tonsillar surface culture, then antibiotics also effective against H influenzae besides the target microorganisms may be chosen.

First Report of Pantoea sp. Induced Soft Rot Disease of Pleurotus eryngii in Korea.

The king oyster mushroom, Pleurotus eryngii, has become a popular crop because of its unique flavor and texture and is cultivated in many areas in Korea. In 2003, symptoms of water-soaked lesions and soft rot in the stipes and pileus of cultivated P. eryngii was observed in Jinju, Korea. Diseased tissue was plated on nutrient media. Dominate colonies were yellow, convex, circular with smooth margins, and had a shiny texture. Computer analysis of the data gathered, using the API kit (50CHE, bioMérieux, Marcy-l'Etoile, France), showed that the strain belongs to the Enterobacteriaceae. Although the API system did not give an exact identification, the metabolic profile of the bacterial strain closely resembled the database profile of Pantoea sp. (positive for acid production from the fermentation of d-fructose, d-galactose, d-glucose, d-trehalose, and d-ribose and negative for oxidase, urease, pectate, and thiosulfate). The 16S rDNA sequence of the bacterium was determined (GenBank Accession No. AY530796). When compared with those in GenBank, the bacterium was determined to belong to the Enterobacteriaceae family of the Gammaproteobacteria, and the highest degree of sequence similarity was found to be with Pantoea ananatis strain BD 588 (97.4%) and Pantoea ananatis strain Pna 97-1 (97.3%). In the phylogenetic tree, the bacterium clearly related to the Pantoea lineage, as evidenced by the high bootstrap value. A BLAST search with 16S rDNA sequence of the bacterium supported the API results that the isolate belongs to a species of Pantoea. Pathogenicity tests of this new Pantoea isolate were carried out with bacterial suspensions (approximately 1 × 106 CFU/ml) that were grown for 24 h in Luria-Bertani broth cultures. These were used to inoculate directly on the mycelia of P. eryngii that had been cultivated for 35 days in a plastic bottle. The water and broth were also inoculated to another set of bottles as a control experiment. Inoculated bottles were incubated in a cultivation room at 16 to 17°C with relative humidity between 80 and 95%. Early symptoms of the disease included a dark brown water drop that developed on hypha and primordium of the mushrooms after 5 to 7 days. After 13 days, water-soaked lesions developed on the stipes and pileus, and the normal growth of the mushrooms was inhibited. An offensive odor then developed along with a severe soft rot that was similar to the disease symptoms observed under natural conditions. Mushrooms in control bottles did not develop symptoms. Koch's postulates were fulfilled by isolating bacteria from typical lesions from inoculated mushrooms that were identical to the inoculated strain in colony morphology and biochemical characteristics. Pantoea ananatis was first reported as a pathogen of pineapple fruit causing brown rot (3). Several bacterial diseases, such as brown blotch on cultivated mushrooms by Pseudomonas tolaasii (2) and bacterial soft rot on winter mushroom by Erwinia carotovora subsp. Carotovora, causing severe damage to mushrooms are known (1). However, no Pantoea sp. induced disease of edible mushroom has been previously reported. To our knowledge, this is the first report of soft rot disease on P. eryngii caused by Pantoea sp.

Abundance of pathogenic Escherichia coli, Salmonella typhimurium and Vibrio cholerae in Nkonkobe drinking water sources

In order to study the prevalence of enteric pathogens capable of causing infection and disease in the rural communities of Nkonkobe, bacterial isolates were collected from several surface water and groundwater sources used by the community for their daily water needs. By making use of selective culture media and the 20E API kit, presumptive Escherichia coli, Salmonella spp. and Vibrio cholerae isolates were obtained and then analysed by polymerase chain reaction assays (PCR). The PCR successfully amplified from water samples a fragment of E. coli uidA gene that codes for beta-D-glucuronidase which is a highly specific characteristic of enteropathogenic E. coli, enterotoxigenic E. coli and entero-invasive E. coli. The PCR also amplified the epsM gene from water samples containing toxigenic V. cholerae. Although E. coli was mostly detected in groundwater sources, toxigenic V. cholerae was detected in both surface and groundwater sources. There was a possibility of Salmonella typhimurium in Ngqele and Dyamala borehole water samples. The presence of these pathogenic bacteria in the above drinking water sources may pose a serious health risk to consumers.

Bacillus sp. MS202에 의한 Dinitroaniline계 제초제인 Pendimethalin의 부분환원

The persistence of pendimethalin in soil and ground water has an injurious effect on ecosystem. Pendimethalin-degrading bacterium was isolated from Masan, Gyeongnam province and temporarily identified as Bacillus sp. MS202 by the analysis of API CHB50, kit, FAME, and 16S rDNA sequence. from the analysis of pnedimethalin metabolite using TLC, GC, and GC-MS, we found that the degradation of pendimethalin by Bacillus sp. MS202 did not result in the dealkylated form, but the formation of the reduced compound, 6-amino-2-nitro-N(1-ethylpropyl)-3,4-xylidine or 2- amino-6-nitro-N(1-ethylpropyl)-3,4-xylidine.

Optimization of the Production of Fibrinolytic Enzyme from Bacillus firmus NA-1 in Fermented Soybeans

Bacillus strains capable of producing fibrinolytic enzyme were isolated from traditional fermented Korean soybean paste and Japanese fermented soybean (Natto). Among the 16 strains, a selected Bacillus sp. was identified as Bacillus firmus, with 80.7% homology, by API kit analysis. Seed starter of B. firmus NA-1 was prepared with 5% soymilk prepared from micronized soybean powder. To produce fibrinolytic enzyme by B. firmus NA-1 the liquid culture was performed with NB broth (pH 7.0) fortified with 1% galactose, 0.1% tryptone, and 0.5% K₂HPO₄, by shaking with 180 rpm at 37℃. Fibrinolytic enzyme activity reached the highest value at 7.8 unit/mL (plasmin unit) after fermentation for 72 hr. The crude fibrinolytic enzyme showed higher relative activity in the range of pH 7.0～9.0. The activity of crude fibrinolytic enzyme was well maintained even after concentration by the vacuum evaporation at 50℃ for 1 hr.

Isolation and Identification of Pathogenic Microorganisms from Soybean Sprouts

Raw soybean sprouts were tested for contamination with the following bacteria which have potential for pathogenesis or food spoilage: Salmonella spp., Escherichia coli O157:H7, Yersinia enterocolitica, Vibrio parahaemolyticus, Aeromonas hydrophila, Plesidomonas shigeloides, Pseudomonas aeruginosa, Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Clostridium perfringens, Campylobacter jejuni, Erwinia spp., and Fusarium spp. Three of the above strains were isolated from the sprouts, and identified by morphological and biochemical methods including an API kit and ATB automated identification system. The isolate cultured in Cereus selective agar, a selective medium, was a Gram-positive, rod shaped, anaerobic spore former. The biochemical and culture tests revealed the following characteristics: catalase-positive, no growth on Simmon's citrate, NO₂ production and requirement of arginine for growth; the ATB automated identification system gave 99.8% agreement for the identification of Bacillus cereus to the species level. The isolate cultured in MacConkey agar selective medium was Gram-negative, rod shaped and a gas former; the ATB-system gave 99.9% agreement for the identification of Aeromonas hydrophila to the species level. The isolate found in Pseudomonas isolation agar was Gramnegative, rod shaped, cytochrome oxidase-positive, a reducer of nitrates to nitrogen, and pyocyanin producer; the ATB-system gave 99.9% agreement for the identification of Pseudomonas aeruginosa to the species level. These results indicate that the three bacteria species present in the soybean sprouts were Bacillus cereus, Aeromonas hydrophila, and Pseudomonas aeruginosa. Salmonella spp., Escherichia coli O157:H7, and Yersinia enterocolitica; which are associated with serious disease in humans, were not isolated from soybean sprouts examined in this study.

Characterisation of the dominant microbiota of Sudanese fermented milk Rob

The predominant microorganisms in the Sudanese traditional fermented dairy product Rob from cows’ milk were isolated and identified by using morphological, physiological and molecular typing techniques. From seven production sites in Khartoum, samples of Rob used as inocula for fermentation were analysed by the determination of the cfu mL−1 on MRS, M17, potato dextrose agar and plate count agar. Samples of inocula from two production sites were used for Rob fermentation in the laboratory followed by similar microbiological analysis. The results obtained showed that the Rob inocula contained lactococci and lactobacilli in the range of 107–108 and yeasts in the range of 106–107 cfu mL−1. During the course of the two laboratory fermentations, the lactococci and lactobacilli increased to 108 cfu mL−1, the yeasts to 107 cfu mL−1 and the aerobic mesophilic counts decreased to 105 cfu mL−1. The pH of the inocula ranged between 3.4 and 3.6 and the pH of Rob produced in the laboratory was 4.2–4.5. Using the internal transcribed spacer-polymerase chain reaction (PCR) technique, 189 representative strains of lactic acid bacteria and 109 representative isolates of yeasts were divided into nine and two groups, respectively, according to the size of the PCR product formed. Representative members of all groups were identified by the API 50 CH and the ID 32 API kits for lactic acid bacteria and yeasts, respectively. Confirmation of identification of lactic acid bacteria species was achieved by sequencing the 16S rRNA gene. The predominant lactic acid bacteria in Rob fermentation were found to be Lactobacillus fermentum, Lactobacillus acidophilus, Lactococcus lactis, and Streptococcus salivarius. The predominant yeasts were found to be Saccharomyces cerevisiae and Candida kefyr.

Identification of Pseudomonas pseudomallei in clinical practice: use of simple screening tests and API 20NE.

The API 20NE kit and a simple screening system involving Gram's stain, the oxidase reaction, colistin and gentamicin resistance, and colonial characteristics on a differential agar medium, were used to test 400 strains of Pseudomonas pseudomallei. The API kit identified 390 (97.5%) strains correctly on first testing and all but one of the remainder on second testing. Only one strain was initially misidentified (as Ps cepacia). The screening system was 100% accurate in identifying Ps pseudomallei. In non-endemic areas the API 20NE kit may be used to identify sporadic imported strains of Ps pseudomallei. Such kits may also help to delineate the geographical distribution of melioidosis. In endemic areas the screening tests described offer a cheap, simple, and accurate means of presumptively identifying Ps pseudomallei from clinical specimens.

Characteristics of isolates of Lactobacillus fermentum from the rumen of sheep

A detailed characterization of four representative Lactobacillus isolates from the rumen was undertaken after tests with API CH50 kits had indicated that they differed from currently recognized species. These isolates are shown to be related to Lactobacillus fermentum, although they differ from the type and reference strains of this species in sodium dodecyl sulphate polyacrylamide gel electrophoresis patterns and electrophoretic mobility of LDH. It seemed that certain heterofermentative lactobacilli could give negative results for some fermentation tests (particularly fructose and lactose) in API kits, whilst showing good growth on the same substrates in conventional tests.

Description and interest of the new API kit (API 20 EC) for identification of coliform enterobacteria

Description and interest of the new API kit (API 20 EC) for identification of coliform enterobacteria