SIST-TS CEN ISO/TS 10272-3:2010
(Main)Microbiology of food and animal feeding stuffs - Horizontal method for detection and enumeration of Campylobacter spp. - Part 3: Semi-quantitative method (ISO/TS 10272-3:2010)
Microbiology of food and animal feeding stuffs - Horizontal method for detection and enumeration of Campylobacter spp. - Part 3: Semi-quantitative method (ISO/TS 10272-3:2010)
This part of ISO 10272 describes a horizontal method for the semi-quantitative determination of
Campylobacter spp. It is applicable to products intended for human consumption or for the feeding of animals, and to environmental samples in the area of food production and food handling. However, it is possible that this part of ISO 10272 is not appropriate in every detail for certain products, deviations from it being made necessary for technical reasons. It is possible that this part of ISO 10272 is not applicable at all to some other products.
Mikrobiologie von Lebensmitteln und Futtermitteln - Horizontales Verfahren zum Nachweis und zur Zählung von Campylobacter spp. - Teil 3: Semiquantitatives Verfahren (ISO/TS 10272-3:2010)
Dieser Teil von ISO/TS 10272 legt ein horizontales Verfahren zur semiquantitativen Bestimmung von Campylobacter spp. fest.
Dieses Dokument gilt für Produkte, die für den menschlichen Verzehr oder als Futtermittel bestimmt sind, und für Umgebungsproben im Bereich der Herstellung und der Behandlung von Lebensmitteln. Es ist jedoch möglich, dass dieser Teil von ISO/TS 10272 nicht bis ins Einzelne für bestimmte Produkte geeignet ist, dass Abweichungen davon aus fachlichen Gründen erforderlich sind. Es ist möglich, dass dieser Teil von ISO/TS 10272 auf einige andere Produkte überhaupt nicht anwendbar ist.
Microbiologie des aliments - Méthode horizontale pour la recherche et le dénombrement de Campylobacter spp. - Partie 3: Méthode semi-quantitative (ISO/TS 10272-3:2010)
L'ISO/TS 10272-3:2010 décrit une méthode horizontale pour la détermination semi-quantitative de Campylobacter spp.
Elle est applicable aux produits destinés à une consommation humaine ou aux aliments pour animaux et à des échantillons environnementaux dans le domaine de la production alimentaire et de la manipulation des aliments. Toutefois, il est possible que l'ISO/TS 10272-3:2010 ne convienne pas en tout point pour certains produits, des écarts étant rendus nécessaires par des raisons techniques. Il est possible que l'ISO/TS 10272-3:2010 ne s'applique pas du tout à certains autres produits.
Mikrobiologija živil in krme - Horizontalna metoda za ugotavljanje prisotnosti in števila bakterij Campylobacter spp. - 3. del: Semikvantitativna metoda (ISO/TS 10272-3:2010)
Ta del ISO 10272 opisuje horizontalno metodo za semikvantitativno metodo določevanja bakterij Campylobacter spp. Velja za proizvode, namenjene za človeško porabo ali za krmljenje živali ter za okoljske vzorce v območjih proizvodnje hrane in ravnanja z hrano. Vendar je možno, da ta del ISO 10272 ni v vseh podrobnostih primeren za določene proizvode, zato so odstopanja zaradi tehničnih razlogov potrebna. Možno je, da ta del ISO 10272 sploh ne velja za nekatere druge proizvode.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST-TS CEN ISO/TS 10272-3:2010
01-september-2010
Mikrobiologija živil in krme - Horizontalna metoda za ugotavljanje prisotnosti in
števila bakterij Campylobacter spp. - 3. del: Semikvantitativna metoda (ISO/TS
10272-3:2010)
Microbiology of food and animal feeding stuffs - Horizontal method for detection and
enumeration of Campylobacter spp. - Part 3: Semi-quantitative method (ISO/TS 10272-
3:2010)
Mikrobiologie von Lebensmitteln und Futtermitteln - Horizontales Verfahren zum
Nachweis und zur Zählung von Campylobacter spp. - Teil 3: Semiquantitatives Verfahren
(ISO/TS 10272-3:2010)
Microbiologie des aliments - Méthode horizontale pour la recherche et le dénombrement
de Campylobacter spp. - Partie 3: Méthode semi-quantitative (ISO/TS 10272-3:2010)
Ta slovenski standard je istoveten z: CEN ISO/TS 10272-3:2010
ICS:
07.100.30 Mikrobiologija živil Food microbiology
SIST-TS CEN ISO/TS 10272-3:2010 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST-TS CEN ISO/TS 10272-3:2010
TECHNICAL SPECIFICATION
CEN ISO/TS 10272-3
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
March 2010
ICS 07.100.30
English Version
Microbiology of food and animal feeding stuffs - Horizontal
method for detection and enumeration of Campylobacter spp. -
Part 3: Semi-quantitative method (ISO/TS 10272-3:2010)
Microbiologie des aliments - Méthode horizontale pour la Mikrobiologie von Lebensmitteln und Futtermitteln -
recherche et le dénombrement de Campylobacter spp. - Horizontales Verfahren zum Nachweis und zur Zählung von
Partie 3: Méthode semi-quantitative (ISO/TS 10272-3:2010) Campylobacter spp. - Teil 3: Semiquantitatives Verfahren
(ISO/TS 10272-3:2010)
This Technical Specification (CEN/TS) was approved by CEN on 28 December 2009 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available
promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)
until the final decision about the possible conversion of the CEN/TS into an EN is reached.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2010 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN ISO/TS 10272-3:2010: E
worldwide for CEN national Members.
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CEN ISO/TS 10272-3:2010 (E)
Contents Page
Foreword .3
2
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CEN ISO/TS 10272-3:2010 (E)
Foreword
This document (CEN ISO/TS 10272-3:2010) has been prepared by Technical Committee ISO/TC 34 "Food
products" in collaboration with Technical Committee CEN/TC 275 “Food analysis - Horizontal methods” the
secretariat of which is held by DIN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria, Croatia, Cyprus,
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of ISO/TS 10272-3:2010 has been approved by CEN as a CEN ISO/TS 10272-3:2010 without any
modification.
3
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SIST-TS CEN ISO/TS 10272-3:2010
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SIST-TS CEN ISO/TS 10272-3:2010
TECHNICAL ISO/TS
SPECIFICATION 10272-3
First edition
2010-03-01
Microbiology of food and animal feeding
stuffs — Horizontal method for detection
and enumeration of Campylobacter
spp. —
Part 3:
Semi-quantitative method
Microbiologie des aliments — Méthode horizontale pour la recherche et
le dénombrement de Campylobacter spp. —
Partie 3: Méthode semi-quantitative
Reference number
ISO/TS 10272-3:2010(E)
©
ISO 2010
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SIST-TS CEN ISO/TS 10272-3:2010
ISO/TS 10272-3:2010(E)
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ii © ISO 2010 – All rights reserved
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Contents Page
Foreword .iv
Introduction.v
1 Scope.1
2 Normative references.1
3 Terms and definitions .1
4 Principle.2
5 Culture media and reagents .2
6 Apparatus.3
7 Sampling.3
8 Preparation of test sample .4
9 Procedure.4
9.1 General .4
9.2 Test portion, initial suspension and dilutions.4
9.3 Enrichment.4
9.4 Isolation.4
9.5 Confirmation of Campylobacter spp. .5
9.6 Identification of Campylobacter spp. (optional).6
10 Calculation and expression of results .8
10.1 Method of calculation.8
10.2 Precision.8
11 Test report.9
Annex A (normative) Diagram of procedure .10
Annex B (normative) Composition and preparation of culture media and reagents.11
Bibliography.17
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Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
In other circumstances, particularly when there is an urgent market requirement for such documents, a
technical committee may decide to publish other types of document:
⎯ an ISO Publicly Available Specification (ISO/PAS) represents an agreement between technical experts in
an ISO working group and is accepted for publication if it is approved by more than 50 % of the members
of the parent committee casting a vote;
⎯ an ISO Technical Specification (ISO/TS) represents an agreement between the members of a technical
committee and is accepted for publication if it is approved by 2/3 of the members of the committee casting
a vote.
An ISO/PAS or ISO/TS is reviewed after three years in order to decide whether it will be confirmed for a
further three years, revised to become an International Standard, or withdrawn. If the ISO/PAS or ISO/TS is
confirmed, it is reviewed again after a further three years, at which time it must either be transformed into an
International Standard or be withdrawn.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO/TS 10272-3 was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 9,
Microbiology.
ISO 10272 consists of the following parts, under the general title Microbiology of food and animal feeding
stuffs — Horizontal method for detection and enumeration of Campylobacter spp.:
⎯ Part 1: Detection method
⎯ Part 2: Colony count technique [Technical Specification]
⎯ Part 3: Semi-quantitative method [Technical Specification]
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ISO/TS 10272-3:2010(E)
Introduction
Because of the large variety of food and feed products, ISO 10272 may not be appropriate in every detail for
certain products, and for some other products it may be necessary to use different methods.
Nevertheless, in all cases, every attempt should be made to apply ISO 10272 as far as possible, any
deviations being made only if absolutely necessary for technical reasons.
When ISO 10272 is next reviewed, account will be taken of all information then available regarding the extent
to which the methods have been followed and the reasons for deviations from it in the case of particular
products. The harmonization of test methods cannot be immediate and, for certain groups of products,
International Standards and/or national standards may already exist that do not comply with ISO 10272. It is
hoped that, when such standards are reviewed, they will be changed to comply with ISO 10272, so that
eventually the only remaining departures are those necessary for well-established technical reasons.
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SIST-TS CEN ISO/TS 10272-3:2010
TECHNICAL SPECIFICATION ISO/TS 10272-3:2010(E)
Microbiology of food and animal feeding stuffs — Horizontal
method for detection and enumeration of Campylobacter spp. —
Part 3:
Semi-quantitative method
1 Scope
This part of ISO 10272 describes a horizontal method for the semi-quantitative determination of
Campylobacter spp.
It is applicable to products intended for human consumption or for the feeding of animals, and to
environmental samples in the area of food production and food handling. However, it is possible that this part
of ISO 10272 is not appropriate in every detail for certain products, deviations from it being made necessary
for technical reasons. It is possible that this part of ISO 10272 is not applicable at all to some other products.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 6887 (all parts), Microbiology of food and animal feeding stuffs — Preparation of test samples, initial
suspension and decimal dilutions for microbiological examination
ISO 7218, Microbiology of food and animal feeding stuffs — General requirements and guidance for
microbiological examinations
ISO/TS 11133-1, Microbiology of food and animal feeding stuffs — Guidelines on preparation and production
of culture media — Part 1: General guidelines on quality assurance for the preparation of culture media in the
laboratory
ISO/TS 11133-2:2003, Microbiology of food and animal feeding stuffs — Guidelines on preparation and
production of culture media — Part 2: Practical guidelines on performance testing of culture media
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
Campylobacter
〈food and feed Campylobacter microbiology〉 genus of microorganisms forming characteristic colonies on solid
selective media when incubated microaerobically at 41,5 °C, but not at 25 °C, and which possess the
characteristic motility and biochemical and growth properties described when the tests are conducted in
accordance with this part of ISO 10272
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ISO/TS 10272-3:2010(E)
NOTE The most frequently encountered species are Campylobacter jejuni and C. coli. Other species have, however,
been described (C. lari, C. upsaliensis and some others).
3.2
semi-quantitative determination
〈food and feed Campylobacter microbiology〉 determination of the level of Campylobacter contamination, when
a low number is expected, or if the level of accompanying flora is relatively high
4 Principle
4.1 General. The semi-quantitative determination of Campylobacter spp. requires stages 4.2 to 4.4 (see
Figure A.1).
4.2 Enrichment in selective liquid medium. The test portion and decimal dilutions thereof are inoculated
or diluted in the liquid enrichment medium (Bolton broth) and homogenized.
The enrichment medium is incubated at 37 °C for 4 h to 6 h followed by incubation at 41,5 °C for (44 ± 4) h.
4.3 Isolation and selection for confirmation. From the cultures obtained in 4.2, the selective solid
medium modified charcoal cefoperazone deoxycholate agar (mCCD agar) is inoculated, incubated at 41,5 °C
in a microaerobic atmosphere and inspected after (44 ± 4) h to detect the presence of colonies presumed to
be Campylobacter spp. because of their characteristics.
4.4 Confirmation. The colonies presumed to be Campylobacter spp. are subcultured on the non-selective
Columbia blood agar, then confirmed by means of microscopic examination and appropriate biochemical and
growth tests. Optionally, the Campylobacter spp. are identified by specific biochemical tests and antibiotic
sensitivity tests.
5 Culture media and reagents
5.1 General. For current laboratory practice, see ISO 7218, ISO/TS 11133-1 and ISO/TS 11133-2.
NOTE Because of the large number of culture media and reagents and for the clarity of the text, their compositions
and preparations are given in Annex B.
5.2 Liquid enrichment medium: Bolton broth. See B.1.
5.3 Selective plating medium: modified charcoal cefoperazone deoxycholate agar (mCCD agar).
See B.2.
5.4 Confirmation and identification media and reagents.
5.4.1 Columbia blood agar. See B.3.
5.4.2 Brucella broth. See B.4.
5.4.3 Reagent for the detection of oxidase. See B.5.
5.4.4 Hydrogen peroxide solution, 3 % (volume fraction).
5.4.5 Reagents for the detection of hydrolysis of hippurate. See B.6.
5.4.6 Mueller Hinton blood agar. See B.7.
5.4.7 Nalidixic acid discs and cephalothin discs. Each type of disc contains 30 µg of reagent.
5.4.8 Indoxyl acetate discs. See B.8.
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6 Apparatus
Usual microbiological laboratory equipment (see ISO 7218) and, in particular, the following.
6.1 Apparatus for dry sterilization (oven) or wet sterilization (autoclave). See ISO 7218.
6.2 Oven, laminar flow cabinet or incubator, capable of being maintained between 37 °C and 55 °C.
6.3 Incubators, capable of being maintained at (25 ± 1) °C, (37 ± 1) °C and (41,5 ± 1) °C.
6.4 Water bath, capable of being maintained at (37 ± 1) °C.
6.5 Water bath, capable of being maintained between 47 °C and 50 °C.
6.6 pH-meter, accurate to within 0,1 pH units at 25 °C.
6.7 Containers, in particular culture tubes of dimensions 18 mm × 180 mm and 9 mm × 180 mm,
haemolysis tubes of dimensions 13 mm × 75 mm, bottles with non-toxic metal closures and/or flasks of
appropriate capacity with appropriate covers.
6.8 Petri dishes, in glass or plastic, with diameters 90 mm to 100 mm.
6.9 Total-delivery graduated pipettes, with a wide opening, and a nominal capacity of 1 ml and 10 ml,
[1] [2]
graduated in 0,1 ml divisions, ISO 835 class A, and Pasteur pipettes, ISO 7712 .
6.10 Rubber teats, or any other safety system capable of being adapted to the graduated pipettes.
6.11 Sterile loops, of platinum-iridium alloy, nickel-chromium alloy or plastic, approximately 3 mm in
diameter, and wires of the same material, or a glass rod or plastic rod.
A nickel-chromium alloy loop is not suitable for use in the oxidase test (see 9.5.6).
6.12 Forceps, fine, round-ended, of stainless steel.
6.13 Microscope, preferably with phase contrast (for observing the characteristic motility of Campylobacter
spp.).
6.14 Apparatus suitable for achieving a microaerobic atmosphere, with volume fractions of: oxygen,
(5 ± 2) %; carbon dioxide, (10 ± 3) %; optionally hydrogen, u 10 %; the balance being nitrogen. Appropriate
gastight containers are used to hold Petri dishes and/or flasks or bottles of about 350 ml capacity used for the
enrichment broth, e.g. bacteriological anaerobic jars.
NOTE 1 The appropriate microaerobic atmosphere can be obtained using commercially available gas-generating kits,
following precisely the manufacturer's instructions, particularly those relating to the volume of the jar and the capacity of
the gas-generating kit. Alternatively, the jar can be filled with an appropriate gas mixture prior to incubation.
NOTE 2 As an alternative to incubation in a microaerobic atmosphere, the enrichment broth can be incubated in
screw-capped bottles, flasks or tubes filled with enrichment broth, leaving a headspace of less than 20 mm and tightly
screwing on the caps.
7 Sampling
A representative sample should have been sent to the laboratory. It should not have been damaged or
changed during transport or storage.
Sampling is not part of the method specified in this part of ISO 10272. See the specific International Standard
dealing with the product concerned. If no specific International Standard exists, it is recommended that the
parties concerned come to an agreement on this subject.
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Since Campylobacter spp. are very sensitive to freezing but survive best at low temperatures, it is
recommended that samples be stored at (+ 3 ± 2) °C and subjected to analysis as rapidly as possible. Also
take care to prevent the samples from drying.
8 Preparation of test sample
Prepare the test sample in accordance with the relevant part of ISO 6887 dealing with the product concerned.
If ISO 6887 is not appropriate, it is recommended that the parties concerned come to an agreement on this
subject.
9 Procedure
9.1 General
See Figure A.1.
9.2 Test portion, initial suspension and dilutions
9.2.1 Introduce a test portion of x g or x ml (minimum 15 g or 15 ml) from the test sample (Clause 8) into
eight times (120 ml minimum) its volume of the enrichment medium Bolton broth (5.2), and homogenize.
This is the initial suspension.
9.2.2 Transfer an amount of 90 ml of the initial suspension (9.2.1) to a 100 ml bottle. This corresponds to
1
10 g of the test portion. When reading the results, this dilution corresponds to 10 .
9.2.3 Transfer 10 ml of the initial suspension (9.2.1) to a culture tube. When reading the results, this dilution
0
corresponds to 10 . After the next dilution step (9.2.4), 9 ml of this dilution remains. This corresponds to 1 g of
the test portion.
–4 0
9.2.4 Make an ordinary 10-fold dilution series (e.g. to 10 ) from the 10 dilution (9.2.3) by transferring
1,0 ml to tubes containing 9,0 ml Bolton broth. A quantity of 1,0 ml from the highest dilution is discarded, as all
–1 –2
tubes must contain 9,0 ml. When reading the results, these dilutions correspond to 10 , 10 , etc.
9.3 Enrichment
Incubate the test portions and dilutions (9.2.2, 9.2.3 and 9.2.4) in a microaerobic atmosphere (6.14) at 37 °C
for 4 h to 6 h and then at 41,5 °C for (44 ± 4) h.
9.4 Isolation
9.4.1 Using each of the cultures obtained in the enrichment media (9.3), inoculate with a sterile loop (6.11)
the surface of plates of the selective isolation medium mCCD agar (5.3).
9.4.2 Incubate the plates (9.4.1) at 41,5 °C in a microaerobic atmosphere (6.14).
9.4.3 After (44 ± 4) h of incubation, examine the plates for typical and/or suspect colonies of Campylobacter
spp.
The typical colonies are greyish on mCCD agar, often with a metallic sheen, and are flat and moist, with a
tendency to spread. Colonies spread less on drier agar surfaces. Other forms of colonies may occur.
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9.5 Confirmation of Campylobacter spp.
9.5.1 General
As the bacteria rapidly deteriorate in air, follow the procedure described in 9.5.2 to 9.5.6 without any delay.
9.5.2 Selection of colonies for confirmation
9.5.2.1 For confirmation, take from each plate (9.4.3) at least one colony considered to be typical or
suspected as being Campylobacter spp., examine the morphology and motility by microscopic
examination (9.5.3.1) and proceed in the same manner with up to a further four colonies if the first one is
negative.
9.5.2.2 Streak each of the selected colonies on to a Columbia blood agar plate (5.4.1) in order to allow
the development of well-isolated colonies. Incubate the plates in a microaerobic atmosphere at 41,5 °C for
24 h to 48 h. Use the pure cultures for examination of morphology, motility, microaerobic growth at 25 °C,
aerobic growth at 41,5 °C and the presence of oxidase.
9.5.3 Examination of morphology and motility
9.5.3.1 Suspend one colony from the Columbia blood agar plate (9.5.2.2) in 1 ml of Brucella broth (5.4.2)
or in peptone salt solution and examine for morphology and motility using a microscope (6.13).
9.5.3.2 Retain for further examination all cultures (9.5.2.2) in which curved bacilli with a spiralling
“corkscrew” motility are found (9.5.3.1).
9.5.4 Study of growth at 25 °C (microaerobic)
Using the colonies isolated in 9.5.2.2, inoculate with the aid of a loop (6.11) the surface of a Columbia blood
agar plate (5.4.1).
Incubate the plate at 25 °C in a microaerobic atmosphere (6.14) for (44 ± 4) h.
Examine the plate for visible growth of colonies of Campylobacter spp.
9.5.5 Study of growth at 41,5 °C (aerobic)
Using the colonies isolated in 9.5.2.2, inoculate with the aid of a loop (6.11) the surface of a Columbia blood
agar plate (5.4.1).
Incubate the plate at 41,5 °C in an aerobic atmosphere for (44 ± 4) h.
Examine the plate for visible growth of colonies of Campylobacter spp.
9.5.6 Detection of oxidase
Using a platinum-iridium alloy or plastic loop or a glass rod (6.11), take a portion of a well-isolated colony from
each individual plate (9.5.2.2) and streak it on to a filter paper moistened with the oxidase reagent (5.4.3); the
appearance of a mauve, violet or deep blue colour within 10 s indicates a positive reaction. If a commercially
available oxidase test kit is used, follow the manufacturer's instructions.
Confirm the results using positive and negative controls. Examples of suitable control strains are
Pseudomonas aeruginosa NCTC 10662 (positive control), Escherichia coli NCTC 9001 (negative control).
9.5.7 Interpretation
Campylobacter spp. give results in accordance with Table 1.
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Table 1 — Characteristics of Campylobacter spp.
Morphology (9.5.3) small curved bacilli
Motility (9.5.3) characteristic
Microaerobic growth at 25 °C (9.5.4) −
Aerobic growth at 41,5 °C (9.5.5) −
Oxidase (9.5.6) +
Campylobacter spp. are present if at least one colony presents the above characteristics.
9.6 Identification of Campylobacter spp. (optional)
9.6.1 General
Among the Campylobacter spp. growing at 41,5 °C, those most frequently encountered are C. jejuni and
C. coli. Other species have, however, been described (C. lari, C. upsaliensis and some others); the
characteristics given in Table 2 permit their differentiation.
Table 2 — Characteristics of Campylobacter spp.
Characteristic C. jejuni C. coli C. lari C. upsaliensis
Catalase (9.6.2) + + + − or slight
a a b
Nalidixic acid (9.6.3) S S R/S S
Cephalothin (9.6.3) R R R S
c
Hydrolysis of hippurate (9.6.4) + − − −
Indoxyl acetate (9.6.5) + + − +
Key: + = positive; − = negative; S = sensitive; R = resistant.
a
An increase in the resistance to nalidixic acid of C. jejuni and C. coli strains has been shown.
b
Both sensitive and resistant C. lari strains exist.
c
Hippurate-negative C. jejuni strai
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