1、Designation:E142815aStandard Test Method forEvaluating the Performance of Antimicrobials in or onPolymeric Solids Against Staining by Streptomyce species(APink Stain Organism)1This standard is issued under the fixed designation E1428;the number immediately following the designation indicates the yea
2、r oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.INTRODUCTIONWhen certain bacteria and mold species grow on the surface of
3、 flexible or“plasticized”polymers,metabolites such as pigments in the case of certain bacteria and melanin(dark stains from fungalgrowth)cause undesirable stains on the polymer surface.Theses stains may persist even after thesurface growth is removed.This test method is used for determining the perf
4、ormance of antimicrobialagents used in or on synthetic polymeric solids against pink-staining by the actinomycete,Streptomyces species.This organism has been chosen as an indicator organism,although otherorganisms have been known to cause undesirable staining in polymeric solids.1.Scope1.1 This test
5、 method is intended to assess susceptibility offlat two dimensional vinyl films and other solid polymerproducts as well as products that may directly contact vinyl topink-staining by the actinomycete bacteria Streptomyces spe-cies.This test method may not be suitable for highly texturedor porous sub
6、strates.1.2 This test method is not suitable for evaluating dark-pigmented test samples.1.3 A knowledge of microbiological techniques is recom-mended for these procedures.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.5 Th
7、is standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.
8、1 ASTM Standards:2D3273 Test Method for Resistance to Growth of Mold on theSurface of Interior Coatings in an Environmental Cham-berD3274 Test Method for Evaluating Degree of Surface Dis-figurement of Paint Films by Fungal or Algal Growth,orSoil and Dirt AccumulationE2756 Terminology Relating to Ant
9、imicrobial and AntiviralAgents3.Terminology3.1 For definitions of terms used in this standard refer toTerminology E2756.3.2 Definitions:3.2.1 microbially induced stainingundesirable pigmenta-tion or disfiguration of an object due to surface colonization bycertain microorganisms.3.2.1.1 DiscussionBot
10、h bacteria and fungi produce meta-bolic pigments that can result in surface stains on susceptibleobjects.1This test method is under the jurisdiction of ASTM Committee E35 onPesticides,Antimicrobials,and Alternative Control Agentsand is the direct respon-sibility of Subcommittee E35.15 on Antimicrobi
11、al Agents.Current edition approved May 1,2015.Published June 2015.Originallyapproved in 1991.Last previous edition approved in 2015 as E1428 15.DOI:10.1520/E1428-15A.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book
12、of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2.2 Pink stain organism,nrefers to a staining phenom-ena caused by a metabolic pigment p
13、roduced by actinomycetebacteria specifically,Streptomyces species ATCC 25607(de-posited as Streptoverticillium reticulum).34.Summary of Test Method4.1 Test specimens are placed on an agar surface inoculatedwithStreptoverticilliumspeciesandincubated.Afterincubation,test specimens are rated visually b
14、y percentage ofsample area stained.5.Significance and Use5.1 Methods such as D3273 Standard Test Method forResistance to Growth of Mold on the Surface of InteriorCoatings in an Environmental Chamber and D3274 StandardTest Method for Evaluating the Degree of Surface Disfigure-ment of Paint Films by F
15、ungal or Algal Growth or Soil or DirtAccumulation provide means for assessing mold and algalstaining on paints.5.2 This test method provides a technique for evaluatingantimicrobials in or on polymeric solids against staining byStreptomyces species,bacteria and should assist in the predic-tion of per
16、formance of treated articles under actual fieldconditions.5.3 Conditioning of the specimens,such as exposure toleaching,weathering,and heat treatment,may have significanteffects on performance of antimicrobials against staining.Determination of these effects is not included in this testmethod.6.Interferences6.1 An interference may be caused by contamination ofplates and agar by unwanted organisms that settle from theenvironment.6.2 Dark pigments mask observation of the pink stain.6.3If contamina
