Chemical disinfectants and antiseptics - Preservation of test organisms used for the determination of bactericidal (including Legionella), mycobactericidal, sporicidal, fungicidal and virucidal (including bacteriophages) activity

This document specifies methods for keeping test organisms used and defined in European Standards for the determination of bactericidal (incl. Legionella pneumophila), mycobactericidal, sporicidal, fungicidal and virucidal (incl. bacteriophages) activity of chemical disinfectants and antiseptics drawn up by CEN/TC 216. These methods for keeping test organisms can only be carried out in connection with at least one of those standards where a reference to this document is established.
NOTE 1   Annex A (informative) contains a non-exhaustive list of test organisms for which this document can be applied.
NOTE 2   European Standards (EN and prEN) where this document is referenced are listed in the Bibliography.
NOTE 3   A specific part on the preservation of bacterial spores could be added once the results of the ongoing ring trials are available.

Chemische Desinfektionsmittel und Antiseptika - Aufbewahrung von Prüforganismen für die Prüfung der bakteriziden (einschließlich Legionella), mykobakteriziden, sporiziden, fungiziden und viruziden (einschließlich Bakteriophagen) Wirkung

Dieses Dokument legt Verfahren zur Haltung von Prüforganismen fest, wie sie in den Europäischen Normen des CEN/TC 216 zur Bestimmung der bakteriziden (einschließlich Legionella pneumophila), myko-bakteriziden, sporiziden, fungiziden und viruziden (einschließlich Bakteriophagen) Wirkung chemischer Desinfektionsmittel und Antiseptika verwendet und festgelegt werden. Diese Verfahren zur Haltung von Prüforganismen können nur in Verbindung mit mindestens einer der Normen erfolgen, in denen auf dieses Dokument verwiesen wird.
ANMERKUNG 1   Anhang A (informativ) enthält eine nicht abschließende Liste von Prüforganismen, auf die dieses Dokument angewendet werden kann.
ANMERKUNG 2   Europäische Normen (EN), die auf dieses Dokument verweisen, sind in den Literaturhinweisen aufgelistet.
ANMERKUNG 3   Eine spezifische Beschreibung über die Aufbewahrung von bakteriellen Sporen könnten hinzugefügt werden, sobald die Ergebnisse der laufenden Ringversuche vorliegen.

Antiseptiques et désinfectants chimiques - Conservation des micro-organismes d'essai utilisés pour la détermination de l'activité bactéricide (Legionella incluses), mycobactéricide, sporicide, fongicide et virucide (bactériophages inclus))

Le présent document spécifie les méthodes de conservation des micro-organismes d’essai utilisées et définies dans les Normes européennes relatives à la détermination de l’activité bactéricide (Legionella pneumophila incluse), mycobactéricide, sporicide, fongicide et virucide (bactériophages inclus) des désinfectants et antiseptiques chimiques établies par le CEN/TC 216. Ces méthodes de conservation des micro-organismes d’essai peuvent être mises en oeuvre uniquement en association avec au moins une des normes citant en référence le présent document.
NOTE 1   L’Annexe A (informative) dresse une liste non exhaustive des micro-organismes d’essai auxquels s’applique le présent document.
NOTE 2   Les Normes européennes (EN) faisant référence au présent document sont indiquées dans la bibliographie.
NOTE 3   Une description spécifique sur la conservation des spores bactériennes peut être ajoutée dès que les résultats des essais interlaboratoires en cours seront disponibles.

Kemična razkužila in antiseptiki - Shranjevanje preskusnih organizmov za določanje baktericidnega (vključno Legionella), mikobaktericidnega, sporocidnega, fungicidnega in virucidnega (vključno bakteriofagi) delovanja

Ta dokument določa metode za shranjevanje preskusnih organizmov, ki se uporabljajo v evropskih standardih in so tam opredeljene za določanje baktericidnega (vkl. Legionella pneumophila), mikobaktericidnega, sporocidnega, fungicidnega in virucidnega (vkl. bakteriofagi) delovanja kemičnih razkužil in antiseptikov, ki jih je pripravil tehnični odbor CEN/TC 216. Te metode za shranjevanje preskusnih organizmov je mogoče izvesti samo v povezavi z vsaj enim od standardov, ki se sklicujejo na ta dokument.
OPOMBA 1:   Dodatek A (informativni) vsebuje nepopoln seznam preskusnih organizmov, za katere je mogoče uporabiti ta dokument.
OPOMBA 2:   Evropski standardi (EN in prEN), ki se sklicujejo na ta dokument, so navedeni v bibliografiji.
OPOMBA 3:   Ko bodo na voljo rezultati primerjalnih preskusov v teku, se lahko doda poseben del o shranjevanju bakterijskih spor.

General Information

Status
Published
Public Enquiry End Date
04-Mar-2019
Publication Date
12-Dec-2021
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
08-Oct-2021
Due Date
13-Dec-2021
Completion Date
13-Dec-2021

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 12353:2022
01-januar-2022
Nadomešča:
SIST EN 12353:2013
Kemična razkužila in antiseptiki - Shranjevanje preskusnih organizmov za
določanje baktericidnega (vključno Legionella), mikobaktericidnega,
sporocidnega, fungicidnega in virucidnega (vključno bakteriofagi) delovanja
Chemical disinfectants and antiseptics - Preservation of test organisms used for the
determination of bactericidal (including Legionella), mycobactericidal, sporicidal,
fungicidal and virucidal (including bacteriophages) activity
Chemische Desinfektionsmittel und Antiseptika - Aufbewahrung von Prüforganismen für
die Prüfung der bakteriziden (einschließlich Legionella), mykobakteriziden, sporiziden,
fungiziden und viruziden (einschließlich Bakteriophagen) Wirkung
Antiseptiques et désinfectants chimiques - Conservation des micro-organismes d'essai
utilisés pour la détermination de l'activité bactéricide (Legionella incluses),
mycobactéricide, sporicide, fongicide et virucide (bactériophages inclus))
Ta slovenski standard je istoveten z: EN 12353:2021
ICS:
07.100.99 Drugi standardi v zvezi z Other standards related to
mikrobiologijo microbiology
71.100.35 Kemikalije za dezinfekcijo v Chemicals for industrial and
industriji in doma domestic disinfection
purposes
SIST EN 12353:2022 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 12353:2022

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SIST EN 12353:2022


EN 12353
EUROPEAN STANDARD

NORME EUROPÉENNE

September 2021
EUROPÄISCHE NORM
ICS 11.080.20; 71.100.35 Supersedes EN 12353:2013
English Version

Chemical disinfectants and antiseptics - Preservation of
test organisms used for the determination of bactericidal
(including Legionella), mycobactericidal, sporicidal,
fungicidal and virucidal (including bacteriophages) activity
Antiseptiques et désinfectants chimiques - Chemische Desinfektionsmittel und Antiseptika -
Conservation des micro-organismes d'essai utilisés Aufbewahrung von Prüforganismen für die Prüfung
pour la détermination de l'activité bactéricide der bakteriziden (einschließlich Legionella),
(Legionella incluses), mycobactéricide, sporicide, mykobakteriziden, sporiziden, fungiziden und
fongicide et virucide (bactériophages inclus) viruziden (einschließlich Bakteriophagen) Wirkung
This European Standard was approved by CEN on 1 February 2021.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

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, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 12353:2021 E
worldwide for CEN national Members.

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SIST EN 12353:2022
EN 12353:2021 (E)
Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Requirements . 6
5 Methods . 7
5.1 Principle . 7
5.2 Test organisms, culture media and reagents . 7
5.2.1 Test organisms . 7
5.2.2 Culture media and reagents . 7
5.2.3 Cell cultures . 14
5.2.4 Host strains for dairy bacteriophages (Lactococcus lactis) . 15
5.3 Apparatus and glassware . 16
5.3.1 General . 16
5.3.2 Usual microbiological laboratory equipment . 16
5.4 Procedure for preservation of test organisms – General . 17
5.4.1 Handling of freeze-dried / frozen test organisms from culture collections . 17
5.4.2 Choice of incubation procedure, agar medium, cell culture/cell line . 17
5.5 Procedure for preservation of bacteria (incl. Legionella, aerobic spore-forming
bacteria, excl. mycobacteria and bacterial spores) and yeasts . 18
5.5.1 Reconstitution of the freeze-dried test organisms . 18
5.5.2 Preparation for storage . 18
5.5.3 Preparation of stock culture / working cultures . 19
5.6 Procedure for preservation of mycobacteria . 19
5.6.1 Reconstitution of the freeze-dried test organisms . 19
5.6.2 Preparation for storage . 19
5.6.3 Preparation of working cultures . 20
5.7 Procedure for preservation of moulds (e.g. Aspergillus brasiliensis) . 20
5.7.1 Reconstitution of the freeze-dried test organism . 20
5.7.2 Preparation for storage . 20
5.7.3 Preparation of stock culture / working cultures . 21
5.8 Procedure for preservation of viruses (except dairy bacteriophages) . 21
5.8.1 Reconstitution of frozen virus . 21
5.8.2 Preparation for storage of stock virus suspension . 21
5.8.3 Preparation of test virus suspension . 21
5.9 Procedure for preservation of bacteriophages . 22
5.9.1 Reconstitution of frozen bacteriophages . 22
5.9.2 Preparation for storage . 22
5.9.3 Preparation of bacteriophages working suspensions . 22
5.10 Verification of the purity and identity of test organisms . 22
5.10.1 General . 22
5.10.2 Information on source of strains . 23
5.10.3 Purity . 23
5.10.4 Identity . 23
5.11 Documentation . 23
2

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SIST EN 12353:2022
EN 12353:2021 (E)
5.11.1 General . 23
5.11.2 Freeze-dried test organism / frozen viruses . 23
5.11.3 Cryovials of frozen test organism . 23
5.11.4 Stock culture . 24
5.11.5 Verification of purity and identity . 24
5.11.6 Storage of documentation . 24
Annex A (informative) Test organisms – Culture collection references and relation to
CEN/TC 216 standards . 25
Annex B (informative) Graphical representations . 29
Bibliography . 34

3

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SIST EN 12353:2022
EN 12353:2021 (E)
European foreword
This document (EN 12353:2021) has been prepared by Technical Committee CEN/TC 216 “Chemical
disinfectants and antiseptics”, the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by March 2022, and conflicting national standards shall
be withdrawn at the latest by March 2022.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 12353:2013.
The document was revised to adapt it to the latest state of science, to correct errors and ambiguities.
The following are the significant technical changes since the last edition:
— the methods of preservation of viruses are described more detailed (5.8);
— MEM is not the only suitable cell culture medium, therefore it was replaced by the general term
“cell culture medium” (5.2.2.17 and in the whole text);
— the description of BCYE Agar for Legionella was added (5.2.2.24);
— the information on source of strains was added (5.10.2);
— the information of the storage of documentation was added (5.11.6);
— Clostrioides difficile (A.3.3) was added;
— the CIP numbers for fungi were deleted (replaced by UMIP numbers) (see A.4);
— the used virus strains are re-drafted (see A.5).
The changes mentioned above have no impact on the test results obtained with reference to the
previous version. Those results are still valid.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: 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, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
4

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SIST EN 12353:2022
EN 12353:2021 (E)
Introduction
Standardized tests for the determination of bactericidal (incl. Legionella pneumophila),
mycobactericidal, sporicidal, fungicidal and virucidal (incl. bacteriophages) activity of chemical
disinfectants and antiseptics necessitate the use of test organisms whose purity and identity have been
verified and whose biological behaviour remains stable. Therefore, it is essential to specify the storage
requirements.
This document aims to describe methods for preservation of test organisms used for such purposes.
5

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SIST EN 12353:2022
EN 12353:2021 (E)
1 Scope
This document specifies methods for keeping test organisms used and defined in European Standards
for the determination of bactericidal (incl. Legionella pneumophila), mycobactericidal, sporicidal,
fungicidal and virucidal (incl. bacteriophages) activity of chemical disinfectants and antiseptics drawn
up by CEN/TC 216. These methods for keeping test organisms can only be carried out in connection
with at least one of those standards where a reference to this document is established.
NOTE 1 Annex A (informative) contains a non-exhaustive list of test organisms for which this document can be
applied.
NOTE 2 European Standards (EN) where this document is referenced are listed in the Bibliography.
NOTE 3 A specific description on the preservation of bacterial spores could be added once the results of the
ongoing ring trials are available.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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.
EN 13610, Chemical disinfectants — Quantitative suspension test for the evaluation of virucidal activity
against bacteriophages of chemical disinfectants used in food and industrial areas — Test method and
requirements (phase 2, step 1)
EN 14885, Chemical disinfectants and antiseptics — Application of European Standards for chemical
disinfectants and antiseptics
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
4 Requirements
Each test organism specified in a CEN/TC 216 European Standard and referred to in this document shall
be handled as described in this document. An overview of the CEN/TC 216 standards and the
specification of which standards products shall comply with in order to support specific microbicidal
activity claims are summarised in EN 14885.
The purity and identity of the preserved test organism shall be verified during the preparation and
regularly during the storage, except for viruses where only the identity is checked before the stock virus
suspension is stored.
The preserved test organisms – including the viruses especially in connection with the used cell lines -
should be checked at regular intervals (at least in the case of longer storage than 14 months) to ensure
that its susceptibility to products has not changed. For all standards where there is no internal standard
implemented the test organisms' susceptibility should be checked using relevant reference substances.
6

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SIST EN 12353:2022
EN 12353:2021 (E)
As long as CEN/TC 216 has not developed specific tests for this purpose any suitable method can be
used e.g. EN 1040 for bacteria, EN 1275 for fungi, EN 14348 for mycobacteria, EN 13623 for Legionella
pneumophila, EN 14476 for viruses or EN 13610 for dairy bacteriophages.
5 Methods
5.1 Principle
A sample of the test organism – in general in freeze-dried form – is obtained from a culture collection.
This sample is cultured, prepared for storage, filled into storage vessels and placed in the deep freeze.
From this sample a stock culture is prepared and subsequently used to prepare working cultures for the
test procedure. In some cases the working cultures are directly prepared from the deep freeze samples.
5.2 Test organisms, culture media and reagents
5.2.1 Test organisms
See Annex A for examples of test organisms.
The documentation on the test organisms should follow 5.10.2 and 5.11.
5.2.2 Culture media and reagents
5.2.2.1 General
The formulas of all media and reagents are given in case commercial ready-to-use material is not used.
It is to be checked that each commercial supplier has established an appropriate quality control system.
All weights of chemical substances given in this document refer to the anhydrous salts unless otherwise
stated. Hydrated forms may be used as an alternative, but the weights required shall be adjusted to
allow for consequent molecular weight differences.
The reagents shall be of analytical grade and/or appropriate for microbiological purposes. They shall be
free from substances that are toxic or inhibitory to the test organisms.
To improve reproducibility, it is recommended that whenever possible, commercially available
dehydrated material is used for the preparation of culture media. The manufacturer's instructions
relating to the preparation of these products should be rigorously followed.
All specified pH values are measured at (20 ± 1) °C.
The media and substances mentioned in 5.2.2 shall be stored under controlled conditions according to
manufacturer's recommendation.
For each culture medium, cell culture and reagent a limitation for use should be fixed.
5.2.2.2 Water
The water shall be freshly glass distilled water and not demineralized water. If distilled water of
adequate quality is not available, water for injections (see bibliography [30]) can be used.
Sterilize in the autoclave (5.3.2.1a). Sterilization is not necessary if the water is used for e.g. preparation
of culture media and subsequently sterilized.
7

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SIST EN 12353:2022
EN 12353:2021 (E)
5.2.2.3 Tryptone Soya Broth (TSB) for bacteria, except Legionella
Tryptone soya broth, consisting of:
Tryptone, pancreatic digest of casein 17,0 g
Soya peptone, papaic digest of soybean meal 3,0 g
Sodium chloride (NaCl) 5,0 g
Water (5.2.2.2) 800,0 ml
Dipotassium phosphate (K HPO ) 2,5 g
2 4
Glucose 2,5 g
Water (5.2.2.2) to 1 000,0 ml
Sterilize in the autoclave (5.3.2.1a). After sterilization the pH of the medium shall be equivalent to
7,2 ± 0,2.
5.2.2.4 Malt Extract Broth (MEB) for fungi
Malt extract broth, consisting of:
Malt extract (food grade, e.g. Christomalt powder from Difal or equivalent that is not highly purified
and not only based on maltose, e.g.
1
20,0 g
malt extract from OXOID)
Water (5.2.2.2) to 1 000,0 ml
Sterilize in the autoclave (5.3.2.1a). After sterilization the pH of the medium shall be equivalent to
5,6 ± 0,2.
5.2.2.5 Cryoprotectant solution for bacteria and fungi
Cryoprotectant solution, consisting of:
Beef extract 3,0 g
Tryptone, pancreatic digest of casein 5,0 g
Glycerol (C H O ) [31] 150,0 g
3 8 3
Water (5.2.2.2) to 1 000,0 ml
Dissolve the constituents in boiling water. Sterilize in the autoclave (5.3.2.1a). After sterilization the pH
of the solution shall be equivalent to 6,9 ± 0,2.
Any commercially available cryoprotectant containing glycerol for preservation of test organisms
equivalent to the solution described above may be used.
If justified, any other equivalent cryoprotectant solution may be used, e.g. for Legionella (5.5.2).

1
This information is given for the information of users of this standard and does not constitute an endorsement of the
products named. Corresponding products supplied by other manufacturers may be used if they can be shown to lead to the
same results.
8

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SIST EN 12353:2022
EN 12353:2021 (E)
5.2.2.6 Middlebrook 7 H 9 broth with 10 % ADC enrichment and glycerol as reconstituent and
cryoprotectant solution for mycobacteria (MADC)
Middlebrook 7 H 9 broth, consisting of:
Middlebrook 7 H 9 broth powder 4,7 g
Glycerol (C H O ) [31] 100,0 ml
3 8 3
Water (5.2.2.2) 800,0 ml
Treat in the autoclave (5.3.2.1a) for a holding time of only 10 min and cool to 45 °C. Add under aseptic
conditions 100 ml Middlebrook ADC enrichment to obtain approximately 1 000,0 ml. The pH of the
medium shall be equivalent to 6,6 ± 0,2.
5.2.2.7 Polysorbate 80 solution
Polysorbate 80 solution, consisting of:
Polysorbate 80 0,5 g
Water (5.2.2.2) to 1 000,0 ml
Sterilize in the autoclave (5.3.2.1a).
5.2.2.8 DMSO as cryoprotectant for cell culture freezing
Dimethyl sulphoxide (DMSO) is used to help protect the cells from rupture by the formation of ice
crystals.
WARNING — Since DMSO is toxic it should be handled with care. It can be absorbed through the skin
and may cause irritation and/or burns. It is teratogenic and an allergen. Suitable gloves should be worn
when handling it.
5.2.2.9 Glutamine solution (3 % m/V solution)
Dissolve 12 g Glutamine in 400 ml of water (5.2.2.2) and sterilize by membrane filtration. The solution
is stored at (−22,5 ± 2,5) °C.
5.2.2.10 TV (Trypsin-Versene)
Dissolve 0,05 g Trypsin in 100 ml of 0,53 mM EDTA (Ethylene diamine tetra acetic acid) and sterilize by
membrane filtration. Store at (4 ± 1) °C.
5.2.2.11 Antibiotic suspension
Chemicals
2
50 million units Penicillin-G
(e.g. Sigma PENNA)
2
50 g Streptomycin sulfate (approx. equal to 750 IU/mg)
(e.g. Sigma Cat: S 6501)
2
25 × 500 000 units Mycostatin
(e.g. Nystatin: Sigma N 3503)
Water (5.2.2.2) to 2,5 l.

2
This information is given for the information of users of this standard and does not constitute an endorsement of the
products named. Corresponding products supplied by other manufacturers may be used if they can be shown to lead to the
same results.
9

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SIST EN 12353:2022
EN 12353:2021 (E)
Preparation
Dissolve vial contents of antibiotics in water (5.2.2.2) and fill up to 2,5 l.
Dispense aseptically into 50 ml and 5 ml aliquots.
Store at − 20 °C. Shake the bottle after thawing.
Dilute the aliquots 200folds (e. g. 5 ml per l) to obtain a final concentration of:
Penicillin 100 units/ml
Streptomycin 100 µg/ml
Mycostatin 25 units/ml
5.2.2.12 Phosphate-buffered saline solution (PBS)
Sodium chloride (NaCl) 8,00 g
Potassium chloride (KCl) 0,20 g
Disodium hydrogen phosphate, 12-hydrate (Na HPO · 12H O) 2,89 g
2 4 2
Potassium phosphate, monobasic (KH PO ) 0,20 g
2 4
Water (5.2.2.2) to 1 000,0 ml
5.2.2.13 Fetal calf serum (FCS)
FCS shall be certified free of viruses and mycoplasma.
Extraneous viruses and mycoplasma may interfere with cell and virus growth resulting in false results.
5.2.2.14 Earle’s BSS
Sodium chloride (NaCl) 68,0 g
Potassium chloride (KCl) 4,0 g
Calcium chloride (CaCl ) 2,0 g
2
Magnesium sulfate, 7-hydrate (MgSO · 7H O) 2,0 g
4 2
Sodium hydrogenphosphate, 2-hydrate (NaH PO · 2H O) 1,4 g
2 2 2
Glucose 10,0 g
Phenol red, 1 % (5.2.2.15) 20,0 ml
Water (5.2.2.2) to 1 000,0 ml
CaCl should be dissolved separately in 100 ml of water (5.2.2.2) and added to the other dissolved
2
reagents just before the solution is brought to its final volume. The solution is 10-fold concentrated. It is
3
sterilized by membrane filtration through a 0,22 µm Millipore or Seitz-type filter and can be stored at
(4 ± 1) °C for 4 weeks.
For use the solution is diluted 10-fold with water (5.2.2.2) and buffered by the addition of 2,5 % of an
8,8 % Sodium hydrogen carbonate (NaHCO ) solution.
3

3 ® ®
Millipore and Seitz are examples of suitable products available commercially. This information is given for
the convenience of users of this standard and does not constitute an endorsement by CEN of this product.
10

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SIST EN 12353:2022
EN 12353:2021 (E)
5.2.2.15 Phenol red (1 % m/V solution)
a) A 1,0 N Sodium hydroxide (NaOH) solution is prepared.
b) 10 g of alcohol soluble Phenol red, European Pharmacopeia [31] are placed in a 100 ml flask
(5.3.2.12); 20 ml of the NaOH solution are added, mixed and allowed to stand for a few minutes.
c) The dissolved dye is transferred in a 1 000 ml volumetric flask (5.3.2.12).
d) Additional 10 ml amounts of the NaOH solution are added to the flask and the dissolved material is
added to the volumetric flask. No more than a total of 70 ml of the NaOH solution should be used.
e) The solution is brought to a final volume of 1 000 ml with water (5.2.2.2) and stored at room
temperature.
5.2.2.16 Sodium bicarbonate (8,8 % w/v solution)
Dissolve 8,8 g sodium bicarbonate in water (5.2.2.2) to 100 ml and sterilize by autoclaving (5.3.2.1a).
Store at (4 ± 1) °C.
5.2.2.17 Cell culture medium
A suitable cell culture medium shall be selected according to the requirements of the cell bank.
5.2.2.18 M17-broth
For maintenance of bacterial host strain (Lactococcus lactis) and propagation of dairy bacteriophages.
Phytone peptone (from soya meal) 5,00 g
Polypeptone peptone (from casein and animal tissue) 5,00 g
Beef extract powder 5,00 g
Yeast extract 2,50 g
D(+)-lactose 5,00 g
Ascorbic acid 0,50 g
Sodium-ß-glycerophosphate 19,00 g
Magnesium sulfate heptahydrate, 7 H O 0,25 g
2
Water (5.2.2.2) 1 000 ml
Sterilize in the autoclave (5.3.2.1a). After sterilization the pH of the medium shall be equivalent to
7,0 ± 0,2.
5.2.2.19 M17-agar (bottom agar)
Bottom agar for quantitative counting of lysis zones (plaques) derived from single infective
bacteriophage particles in the bacterial lawn of the host bacteria.
Add 15 g of agar to 1 000 ml of M17-broth (5.2.2.18). Dissolve the agar by boiling with constant stirring.
Sterilize in the autoclave (5.3.2.1a). After sterilization the pH of the medium shall be equivalent to
7,0 ± 0,2 when measured at 20 °C. When the agar is cooled down to (47 ± 1) °C, add 10 ml of a sterile
1 mol/l CaCl -stock solution (5.2.2.21). Mix gently and pour 15 ml to 18 ml of agar into Petri dishes
2
(5.3.2.10).
11

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5.2.2.20 Overlay agar (top agar, soft agar)
For counting bacteriophages: Dissolve 6,5 g agar in 1 000 ml M17-broth (5.2.2.18) and heat until boiling
with constant stirring. Dispense the molten agar in test tubes (2,5 to 3 ml each).
Sterilize in the autoclave (5.3.2.1a).
For achieving clear phage-derived lysis zones (plaques) in the lawn of host bacterial cells only well-
defined agar should be used which i
...

SLOVENSKI STANDARD
oSIST prEN 12353:2019
01-februar-2019
.HPLþQDUD]NXåLODLQDQWLVHSWLNL6KUDQMHYDQMHSUHVNXVQLKRUJDQL]PRY]D
GRORþDQMHEDNWHULFLGQHJD YNOMXþQR/HJLRQHOOD PLNREDNWHULFLGQHJD
VSRURFLGQHJDIXQJLFLGQHJDLQYLUXFLGQHJD YNOMXþQREDNWHULRIDJL GHORYDQMD
Chemical disinfectants and antiseptics - Preservation of test organisms used for the
determination of bactericidal (including Legionella), mycobactericidal, sporicidal,
fungicidal and virucidal (including bacteriophages) activity
Chemische Desinfektionsmittel und Antiseptika - Aufbewahrung von Testorganismen für
die Prüfung der bakteriziden (einschließlich Legionella), mykobakteriziden, sporiziden,
fungiziden und viruziden (einschließlich Bakteriophagen) Wirkung
Ta slovenski standard je istoveten z: prEN 12353
ICS:
07.100.99 Drugi standardi v zvezi z Other standards related to
mikrobiologijo microbiology
71.100.35 Kemikalije za dezinfekcijo v Chemicals for industrial and
industriji in doma domestic disinfection
purposes
oSIST prEN 12353:2019 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 12353:2019

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oSIST prEN 12353:2019


DRAFT
EUROPEAN STANDARD
prEN 12353
NORME EUROPÉENNE

EUROPÄISCHE NORM

January 2019
ICS 11.080.20; 71.100.35 Will supersede EN 12353:2013
English Version

Chemical disinfectants and antiseptics - Preservation of
test organisms used for the determination of bactericidal
(including Legionella), mycobactericidal, sporicidal,
fungicidal and virucidal (including bacteriophages) activity
 Chemische Desinfektionsmittel und Antiseptika -
Aufbewahrung von Testorganismen für die Prüfung
der bakteriziden (einschließlich Legionella),
mykobakteriziden, sporiziden, fungiziden und
viruziden (einschließlich Bakteriophagen) Wirkung
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 216.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 12353:2019 E
worldwide for CEN national Members.

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Contents Page
European foreword . 5
Introduction . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Requirements . 7
5 Methods . 8
5.1 Principle . 8
5.2 Materials and reagents . 8
5.2.1 Test organisms . 8
5.2.2 Culture media and reagents . 8
5.2.3 Cell cultures . 16
5.2.4 Host strains for dairy bacteriophages (Lactococcus lactis) . 18
5.3 Apparatus and glassware . 18
5.3.1 General . 18
5.3.2 Usual microbiological laboratory equipment . 18
5.4 Procedure for preservation of test organisms – General . 20
5.4.1 Handling of freeze-dried / frozen test organisms from culture collections . 20
5.4.2 Choice of incubation procedure, agar medium, cell culture/cell line . 20
5.5 Procedure for preservation of bacteria (incl. Legionella, spore-forming bacteria,
excl. mycobacteria and bacterial spores) and yeasts . 20
5.5.1 Reconstitution of the freeze-dried test organisms . 20
5.5.2 Preparation for storage . 20
5.5.3 Preparation of stock culture / working cultures . 21
5.6 Procedure for preservation of mycobacteria . 21
5.6.1 Reconstitution of the freeze-dried test organisms . 21
5.6.2 Preparation for storage . 21
5.6.3 Preparation of working cultures . 22
5.7 Procedure for preservation of moulds (e.g. Aspergillus brasiliensis) . 22
5.7.1 Reconstitution of the freeze-dried test organism . 22
5.7.2 Preparation for storage . 22
5.7.3 Preparation of stock culture / working cultures . 23
5.8 Procedure for preservation of viruses (except dairy bacteriophages) . 23
5.8.1 Reconstitution of frozen virus . 23
5.8.2 Preparation for storage of stock virus suspension . 23
5.8.3 Preparation of test virus suspension . 24
5.9 Procedure for preservation of bacteriophages . 24
5.9.1 Reconstitution of frozen bacteriophages . 24
5.9.2 Preparation for storage . 24
5.9.3 Preparation of bacteriophages working suspensions . 25
5.10 Verification of the purity and identity of test organisms . 25
5.10.1 General . 25
5.10.2 Information on source of strains . 25
5.10.3 Purity . 25
5.10.4 Identity . 25
2

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5.11 Documentation . 25
5.11.1 General . 25
5.11.2 Freeze-dried test organism / frozen viruses . 26
5.11.3 Cryovials of frozen test organism . 26
5.11.4 Stock culture . 26
5.11.5 Verification of purity and identity . 26
5.11.6 Storage of documentation . 26
Annex A (informative) Test organisms – Culture collection references and relation to
CEN/TC 216 standards and prENs . 27
A.1 Bacteria (except mycobacteria and spore-forming bacteria) . 27
A.1.1 Enterobacter cloacae . 27
A.1.2 Enterococcus hirae . 27
A.1.3 Enterococcus faecium . 27
A.1.4 Escherichia coli (1) . 27
A.1.5 Escherichia coli (2) K12 . 27
A.1.6 Lactobacillus brevis . 27
A.1.7 Legionella pneumophila, subsp. Pneumophila . 27
A.1.8 Proteus hauseri . 27
A.1.9 Pseudomonas aeruginosa . 28
A.1.10 Salmonella enterica subsp. enterica, Serotype typhimurium . 28
A.1.11 Staphylococcus aureus subsp. aureus . 28
A.2 Mycobacteria . 28
A.2.1 Mycobacterium avium subsp. avium . 28
A.2.2 Mycobacterium terrae . 28
A.3 Spore-forming bacteria . 28
A.3.1 Bacillus cereus . 28
A.3.2 Bacillus subtilis subsp. spizizenii . 28
A.3.3 Clostridium sporogenes . 28
A.4 Fungi (moulds and yeasts) . 29
A.4.1 Aspergillus brasiliensis (former “A. niger”) (mould) . 29
A.4.2 Candida albicans (yeast) . 29
A.4.3 Saccharomyces cerevisiae (1) (yeast) . 29
A.4.4 Saccharomyces cerevisiae (2) var. diastaticus (yeast) . 29
A.5 Viruses . 29
A.5.1 Adenovirus type 5, strain Adenoid 75 . 29
A.5.2 Bovine Enterovirus Type 1(ECBO) . 29
A.5.3 Murine norovirus, strain S99 Berlin . 29
A.5.4 Murine Parvovirus, minute virus of mice, strain Crawford . 29
A.5.5 Poliovirus type 1, Sabin strain LSc-2ab . 29
3

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A.5.6 Vaccinia virus, strain Modified Vaccinia Virus Ankara (MVA) . 30
A.5.7 Vaccinia virus, strain Elstree . 30
A.6 Bacteriophages . 30
A.6.1 Lactococcus lactis subsp. lactis bacteriophage P008 . 30
A.6.2 Lactococcus lactis subsp. lactis bacteriophage P001 . 30
Annex B (informative) Graphical representations. 31
Bibliography . 36

4

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European foreword
This document (prEN 12353:2019) has been prepared by Technical Committee CEN/TC 216 “Chemical
disinfectants and antiseptics”, the secretariat of which is held by AFNOR.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 12353:2013.
The document was revised to adapt it to the latest state of science, to correct errors and ambiguities.
The following are the significant technical changes since the last edition:
— the methods of preservation of viruses are described more detailed (5.8.3);
— the description of BCYE Agar for Legionella was added (5.2.2.24);
— the information on source of strains was added (5.10.2);
— the information of the storage of documentation was added (5.11.6);
— the IP Number for fungi was deleted (see A.4);
— the used virus strains are re-drafted (see A.5).
The changes mentioned above have no impact on the test results obtained with reference to the
previous version. Those results are still valid.
5

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Introduction
Standardized tests for the determination of bactericidal (incl. Legionella pneumophila),
mycobactericidal, sporicidal, fungicidal and virucidal (incl. bacteriophages) activity of chemical
disinfectants and antiseptics necessitate the use of test organisms whose purity and identity have been
verified and whose biological behaviour remains stable. Therefore it is essential to specify the storage
requirements.
This document aims to describe methods for preservation of test organisms used for such purposes.
6

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1 Scope
This document specifies methods for keeping test organisms used and defined in European Standards
for the determination of bactericidal (incl. Legionella pneumophila), mycobactericidal, sporicidal,
fungicidal and virucidal (incl. bacteriophages) activity of chemical disinfectants and antiseptics drawn
up by CEN/TC 216. These methods for keeping test organisms can only be carried out in connection
with at least one of those standards where a reference to this document is established.
NOTE 1 Annex A (informative) contains a non-exhaustive list of test organisms for which this document can be
applied.
NOTE 2 European Standards (EN and prEN) where this document is referenced are listed in the Bibliography.
NOTE 3 A specific part on the preservation of bacterial spores could be added once the results of the ongoing
ring trials are available.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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.
EN 14885, Chemical disinfectants and antiseptics — Application of European Standards for chemical
disinfectants and antiseptics
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 14885 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 Requirements
Each test organism specified in a CEN/TC 216 European Standard and referred to in this document shall
be handled as described in this document.
The purity and identity of the preserved test organism shall be verified during the preparation and
regularly during the storage, except for viruses where only the identity is checked before the stock virus
suspension is stored.
The preserved test organism – except viruses - should be checked at regular intervals (at least in the
case of longer storage than 14 months) to ensure that its susceptibility to products has not changed. As
long as CEN/TC 216 has not developed specific tests for this purpose any suitable method can be used
e.g. EN 1040 for bacteria, EN 1275 for fungi, EN 14348 for mycobacteria, EN 13623 for Legionella
pneumophila, EN 14476 for viruses or EN 13610 for dairy bacteriophages.
7

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5 Methods
5.1 Principle
A sample of the test organism – in general in freeze-dried form - is obtained from a culture collection.
This sample is cultured, prepared for storage, filled into storage vessels and placed in the deep freeze.
From this sample a stock culture is prepared and subsequently used to prepare working cultures for the
test procedure. In some cases the working cultures are directly prepared from the deep freeze samples.
5.2 Materials and reagents
5.2.1 Test organisms
See Annex A for examples of test organisms.
The documentation on the test organisms should follow 5.10.2 and 5.11.3.
5.2.2 Culture media and reagents
5.2.2.1 General
The formulas of all media and reagents are given in case commercial ready-to-use material is not used.
It is to be checked that each commercial supplier has established an appropriate quality control system.
All weights of chemical substances given in this document refer to the anhydrous salts unless otherwise
stated. Hydrated forms may be used as an alternative, but the weights required shall be adjusted to
allow for consequent molecular weight differences.
The reagents shall be of analytical grade and/or appropriate for microbiological purposes. They shall be
free from substances that are toxic or inhibitory to the test organisms.
To improve reproducibility, it is recommended that whenever possible, commercially available
dehydrated material is used for the preparation of culture media. The manufacturer's instructions
relating to the preparation of these products should be rigorously followed.
All specified pH values are measured at (20 ± 1) °C.
For each culture medium, cell culture and reagent a limitation for use should be fixed.
5.2.2.2 Water
The water shall be freshly glass distilled water and not demineralized water. If distilled water of
adequate quality is not available, water for injections (see bibliographic reference [1]) can be used.
Sterilize in the autoclave (5.3.2.1a). Sterilization is not necessary if the water is used for e.g. preparation
of culture media and subsequently sterilized.
5.2.2.3 Tryptone Soya Broth (TSB) for bacteria, except Legionella
Tryptone soya broth, consisting of:
Tryptone, pancreatic digest of casein 17,0 g
Soya peptone, papaic digest of soybean meal 3,0 g
Sodium chloride (NaCl) 5,0 g
Water (5.2.2.2) 800,0 ml
Dipotassium phosphate (K HPO ) 2,5 g
2 4
Glucose 2,5 g
8

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Water (5.2.2.2) to 1 000,0 ml
Sterilize in the autoclave (5.3.2.1a). After sterilization the pH of the medium shall be equivalent to
7,2 ± 0,2.
5.2.2.4 Malt Extract Broth (MEB) for fungi
Malt extract broth, consisting of:
Malt extract (food grade, e.g. Christomalt powder from Difal or equivalent that is not highly purified
and not only based on maltose, e.g.
1
20,0 g
malt extract from OXOID)
Water (5.2.2.2) to 1 000,0 ml
Sterilize in the autoclave (5.3.2.1a). After sterilization the pH of the medium shall be equivalent to
5,6 ± 0,2.
5.2.2.5 Cryoprotectant solution for bacteria, spore-forming bacteria, fungi
Cryoprotectant solution, consisting of:
Beef extract 3,0 g
Tryptone, pancreatic digest of casein 5,0 g
Glycerol (C H O ) [2] 150,0 g
3 8 3
Water (5.2.2.2) to 1 000,0 ml
Dissolve the constituents in boiling water. Sterilize in the autoclave (5.3.2.1a). After sterilization the pH
of the solution shall be equivalent to 6,9 ± 0,2.
Any commercially available cryoprotectant containing glycerol for preservation of test organisms
equivalent to the solution described above may be used.
If justified, any other equivalent cryoprotectant solution may be used, e.g. for Legionella (5.5.2).
5.2.2.6 Middlebrook 7 H 9 broth with 10 % ADC enrichment and glycerol as reconstituent and
cryoprotectant solution for mycobacteria (MADC)
Middlebrook 7 H 9 broth, consisting of:
Middlebrook 7 H 9 broth powder 4,7 g
Glycerol (C H O ) [2] 100,0 ml
3 8 3
Water (5.2.2.2) 800,0 ml
Treat in the autoclave (5.3.2.1a) for a holding time of only 10 min and cool to 45 °C. Add under aseptic
conditions 100 ml Middlebrook ADC enrichment to obtain approximately 1 000,0 ml. The pH of the
medium shall be equivalent to 6,6 ± 0,2.

1
This information is given for the information of users of this standard and does not constitute an endorsement of the
products named. Corresponding products supplied by other manufacturers may be used if they can be shown to lead to the
same results.
9

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5.2.2.7 Polysorbate 80 solution
Polysorbate 80 solution, consisting of:
Polysorbate 80 0,5 g
Water (5.2.2.2) to 1 000,0 ml
Sterilize in the autoclave (5.3.2.1a).
5.2.2.8 DMSO as cryoprotectant for cell culture freezing
Dimethyl sulphoxide (DMSO) is used to help protect the cells from rupture by the formation of ice
crystals.
Since DMSO is toxic it should be handled with care. It can be absorbed through the skin and may cause
irritation and/or burns. It is teratogenic and an allergen. Latex gloves should be worn when handling it.
5.2.2.9 Glutamine solution, 3 %
Dissolve 12 g Glutamine in 400 ml of water (5.2.2.2) and sterilize by membrane filtration. The solution
is stored at (−20 ± 1) °C.
5.2.2.10 TV (Trypsin-Versene)
Dissolve 0,05 g Trypsin in 100 ml of 0,53 mM EDTA (Ethylene diamine tetra acetic acid) and sterilize by
membrane filtration. Store at (4 ± 1) °C.
5.2.2.11 Antibiotic suspension
Chemicals
2
50 million units Penicillin-G
(eg Sigma PEN-K )
50 g Streptomycin sulphate (approx. equal to 750 IU/mg) 2
(eg Sigma Cat: 56501 )
25 × 500,000 units Mycostatin 2
(eg Nystatin: E R Squibb 59150 )
Water (5.2.2.2) to 2,5 l.
Preparation
Dissolve vial contents of antibiotics in water (5.2.2.2) and fill up to 2,5 l.
Dispense aseptically into 50 ml and 5 ml aliquots.
Store at − 20 °C. Shake the bottle after thawing.
Use 5 ml per litre of medium to give a final concentration of:
Penicillin 100 units/ml
Streptomycin 100 µg/ml
Mycostatin 25 units/ml

2
This information is given for the information of users of this standard and does not constitute an endorsement of the
products named. Corresponding products supplied by other manufacturers may be used if they can be shown to lead to the
same results.
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5.2.2.12 Phosphate-buffered saline solution (PBS)
Sodium chloride (NaCl) 8,00 g
Potassium chloride (KCl) 0,20 g
Disodium hydrogen phosphate, 12-hydrate (Na HPO x 12H O) 2,89 g
2 4 2
Potassium phosphate, monobasic (KH PO ) 0,20 g
2 4
Water (5.2.2.2) to 1 000,0 ml
5.2.2.13 Foetal calf serum (FCS)
FCS has to be certified free of viruses and mycoplasma.
Extraneous viruses and mycoplasma may interfere with cell and virus growth resulting in false results.
5.2.2.14 Earle’s BSS
Sodium chloride (NaCl) 68,0 g
Potassium chloride (KCl) 4,0 g
Calcium chloride (CaCl ) 2,0 g
2
Magnesium sulphate, 7-hydrate (MgSO x 7H O) 2,0 g
4 2
Sodium hydrogenphosphate, 2-hydrate (NaH PO x 2H O) 1,4 g
2 2 2
Glucose 10,0 g
Phenol red, 1 % (5.2.2.15) 20,0 ml
Water (5.2.2.2) to 1 000,0 ml
CaCl should be dissolved separately in 100 ml of water (5.2.2.2) and added to the other dissolved
2
reagents just before the solution is brought to its final volume. The solution is 10-fold concentrated. It is
3
sterilized by membrane filtration through a 0,22 µm Millipore or Seitz-type filter and can be stored at
(4 ± 1) °C for 4 weeks.
F
...

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