Conventional Methods to Detect and Isolate Listeria monocytogenes

2007 ◽  
pp. 233-274
Keyword(s):  
Listeria Monocytogenes ◽  
Conventional Methods

scholarly journals ISOLATION OF LISTERIA MONOCYTOGENES FROM FRESH FRUITS AND VEGETABLES

HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 628b-628 ◽  
Author(s):  
Rehana Vahidy ◽  
Farrukh Jahan ◽  
Rizwana Nasim
Keyword(s):  
Public Health ◽  
Listeria Monocytogenes ◽  
Fruits And Vegetables ◽  
Serological Tests ◽  
Two Samples ◽  
Veterinary Importance ◽  
Conventional Methods ◽  
Water Melon

Listeriosis, a fatal food and environment borne disease of public health and veterinary importance, caused by Listeria spp. has not been explored in Pakistan. One hundred and fifty samples of fresh fruits and vegetables collected over a period of 12 months from various localities of Karachi city were screened according to the standard protocols. Suspected isolates were subjected to conventional methods for identification which included morphological, cultural, biochemical and serological tests. Out of 30 samples each of papaya, water melon and cantaloupe, and 15 each of cucumber, tomato, radish and carrot, Listeria monocytogenes was isolated from two samples of papaya and tomato each and one sample of water melon and cucumber each. It is inferred that fruits and vegetables, if not handled hygienically and served fresh, may be responsible for the transmission of listeriosis.

Comparison of Oxygen Scavengers for Their Ability to Enhance Resuscitation of Heat-injured Listeria monocytogenes

1995 ◽  
Vol 58 (3) ◽  
pp. 244-250 ◽  
Author(s):  
J. R. PATEL ◽  
C.-A. HWANG ◽  
L. R. BEUCHAT ◽  
M. P. DOYLE ◽  
R. E. BRACKETT
Keyword(s):  
Listeria Monocytogenes ◽  
Incubation Time ◽  
Skim Milk ◽  
Oxygen Scavengers ◽  
Sodium Pyruvate ◽  
Percentage Recovery ◽  
Cysteine Hydrochloride ◽  
Whole Milk ◽  
Conventional Methods ◽  
Optimal Incubation

The recovery of heat-injured Listeria monocytogenes Scott A in Fraser broth (FB) supplemented with sodium thioglycolate, sodium pyruvate, L-(+)-cysteine hydrochloride, catalase or Oxyrase? was studied. After 3 h of incubation at 30°C, recovery was enhanced by all oxygen scavengers except sodium pyruvate. Oxyrase? (0.005 U ml−1) promoted the highest recovery (34%) compared to recovery in control broth (19%). All oxygen scavengers enhanced the recovery of injured L. monocytogenes in FB within 6 h of incubation. After 6 h at 30°C, 49 and 55% of injured cells underwent resuscitation in FB containing 2.5 mg of sodium pyruvate ml−1 and 400 μg of catalase ml−1, respectively, compared to 24% resuscitation in FB not supplemented with oxygen scavengers. The percentage recovery was increased as the incubation time was extended to 6 and 24 h. Nearly all injured cells were recovered within 24 h of incubation, regardless of supplementation of FB with oxygen scavengers. Fraser broth containing 2.5 mg of sodium pyruvate ml−1, 400 μg of catalase ml−1 or 0.01 U of Oxyrase? ml−1 were tested to determine the optimal incubation time and temperature for recovering heat-injured L. monocytogenes. Percentage recovery of injured cells increased with an increase in temperature from 25 to 30°C and from 30 to 35°C. The highest percentage of injured cells recovered was observed in FB containing 400 μg of catalase ml−1 (67%) and 0.01 U of Oxyrase? ml−1 (68%) within 6 h of incubation at 35°C. Catalase (400 μg ml−1) and Oxyrase? (0.01 U ml−1) in FB resulted in significantly higher recovery of injured cells from heated whole milk; however, recovery of injured cells from heated skim milk was not significantly higher. Enrichment in FB containing catalase or Oxyrase? has potential for recovering heat-injured L. monocytogenes cells within 6 h compared to 24 h required in conventional methods.

scholarly journals Isolation and Characterization of Listeria monocytogenes Isolates from Ready-To-Eat Foods in Florida

2006 ◽  
Vol 72 (7) ◽  
pp. 5073-5076 ◽  
Author(s):  
Yuelian Shen ◽  
Yan Liu ◽  
Yifan Zhang ◽  
Jennifer Cripe ◽  
William Conway ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Listeria Monocytogenes ◽  
Antibiotic Susceptibility ◽  
Food Samples ◽  
Multiple Antibiotic Resistance ◽  
Isolation And Characterization ◽  
Lineage 2 ◽  
Conventional Methods ◽  
Specific Bacteriophage

ABSTRACT Of 3,063 ready-to-eat food samples tested, 91 (2.97%) were positive for Listeria monocytogenes, and lineage 1 strains outnumbered lineage 2 strains 57 to 34. Seventy-one isolates (78%) exhibited multiple antibiotic resistance, and an L. monocytogenes-specific bacteriophage cocktail lysed 65 of 91 (71%) isolates. Determining phage, acid, and antibiotic susceptibility phenotypes enabled us to identify differences among strains which were otherwise indistinguishable by conventional methods.

Occurrence of Campylobacter and Listeria monocytogenes in a Poultry Processing Plant

2005 ◽  
Vol 68 (9) ◽  
pp. 1903-1906 ◽  
Author(s):  
MERCEDES G. R. REITER ◽  
CAMILA M. M. BUENO ◽  
CARMEN LÓPEZ ◽  
R. JORDANO
Keyword(s):  
Listeria Monocytogenes ◽  
Processing Plant ◽  
Southern Brazil ◽  
Poultry Products ◽  
Sampling Points ◽  
Poultry Processing ◽  
Conventional Methods

The occurrence of Campylobacter and Listeria monocytogenes was studied in 645 samples from surfaces, water, and poultry products (chicken carcasses, chicken parts, viscera, and spoils) in a poultry processing plant in southern Brazil. The automated mini-VIDAS system was used to detect the presence of Campylobacter and L. monocytogenes on the samples. The positive samples were confirmed by conventional methods. Campylobacter and L. monocytogenes were found in 16.6 and 35.6% of the analyzed samples, respectively. The sampling points with the highest Campylobacter incidence were intestine (63.3%, 19 of 30 samples), gallbladder (46.7%, 14 of 30), carcasses before evisceration (33.33%, 10 of 30), and carcasses after plucking (30%, 9 of 30). For L. monocytogenes, the majority of positive samples were from frozen breast (100%, 15 of 15 samples), frozen wing (93.3%, 14 of 15), fresh breast (83.3%, 25 of 30), fresh wing (80%, 24 of 30), skin of breast and leg (76.7%, 23 of 30), frozen leg (60%, 9 of 15), and fresh leg (50%, 15 of 30).

scholarly journals Prevalence of Listeria monocytogenes and other Listeria spp. in gulls feeding on Zagreb landfill site, Croatia

2021 ◽  
Vol 53 (4) ◽  
Author(s):  
Andrea Humski ◽  
Luka Jurinović ◽  
Tajana Amšel Zelenika ◽  
Biljana Ječmenica ◽  
Fani Krstulović ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Wild Birds ◽  
Landfill Site ◽  
First Results ◽  
Larus Michahellis ◽  
Conventional Methods ◽  
Prevalent Species

Gulls, as migratory wild birds are known that can spread different pathogens over long distances. Aim of this study was to access prevalence of different Listeria species in their population fed at the Zagreb landfill site. Altogether, 390 gulls of three species were sampled: Yellow-legged Gull, Larus michahellis; Black-headed Gull, L. ridibundus and Common Gull, L. canus. Most prevalent species was L. innocua (14.4%), while L. monocytogenes was found in 11.3 % of tested samples. The presence of other species was found in a smaller percentage, namely L. welshimeri (1.3%), L. ivanovii (0.5%) and L. seeligeri (0.3%). Serotyping of L. monocytogenes isolates was performed using both molecular and conventional methods, and most isolates belonged to serotypes 1/2a and 1/2b. To the best of our knowledge, this study reports the first results of research on the presence of L. monocytogenes and other Listeria spp. in wild birds in Croatia.

Spin-polarized Scanning Electron Microscopy

1990 ◽  
Vol 48 (4) ◽  
pp. 768-769
Author(s):  
Kazuyuki Koike ◽  
Hideo Matsuyama
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Speed ◽  
Magnetic Thin Films ◽  
Electron Spin Polarization ◽  
Acquisition Time ◽  
Magnetization Direction ◽  
Spin Polarized ◽  
Conventional Methods ◽  
Scanning Electron

Spin-polarized scanning electron microscopy (spin SEM), where the secondary electron spin polarization is used as the image signal, is a novel technique for magnetic domain observation. Since its first development by Koike and Hayakawa in 1984, several laboratories have extensively studied this technique and have greatly improved its capability for data extraction and its range of applications. This paper reviews the progress over the last few years.Almost all the high expectations initially held for spin SEM have been realized. A spatial resolution of several hundreds angstroms has been attained, which is nearly one order of magnitude higher than that of conventional methods for thick samples. Quantitative analysis of magnetization direction has been performed more easily than with conventional methods. Domain observation of the surface of three-dimensional samples has been confirmed to be possible. One of the drawbacks, a long image acquisition time, has been eased by combining highspeed image-signal processing with high speed scanning, although at the cost of image quality. By using spin SEM, the magnetic structure of a 180 degrees surface Neel wall, magnetic thin films, multilayered films, magnetic discs, etc., have been investigated.

The Need Inventory of Sensation Seeking (NISS)

2012 ◽  
Vol 28 (1) ◽  
pp. 11-18 ◽  
Author(s):  
Marcus Roth ◽  
Philipp Hammelstein
Keyword(s):  
Sensation Seeking ◽  
Reliability And Validity ◽  
Assessment Method ◽  
Factorial Structure ◽  
Conventional Methods ◽  
New Research ◽  
Sensation Seeking Scale ◽  
Temperamental Trait ◽  
Nonclinical Study

Based on the conception of sensation seeking as a need rather than a temperamental trait ( Hammelstein, 2004 ), we present a new assessment method, the Need Inventory of Sensation Seeking (NISS), which is considered to assess a motivational disposition. Three studies are presented: The first examined the factorial structure and the reliability of the German versions of the NISS; the second study compared the German and the English versions of the NISS; and finally, the validity of the NISS was examined in a nonclinical study and compared to the validity of conventional methods of assessing sensation seeking (Sensation Seeking Scale – Form V; SSS-V). Compared to the SSS-V, the NISS shows better reliability and validity in addition to providing new research possibilities including application in experimental areas.

Use of essential oil treatments to control the Listeria monocytogenes growth in various food commodities

Planta Medica ◽  
2008 ◽  
Vol 74 (09) ◽  
Author(s):  
NG Chorianopoulos ◽  
PN Skandamis ◽  
GJE Nychas ◽  
SA Haroutounian
Keyword(s):  
Listeria Monocytogenes ◽  
Essential Oil ◽  
Food Commodities
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