Microbiology basic Techniques involved in lab

Students can learn the basic terms in the microbiology field

1. MICROBIOLOGY AND
MICROBIAL TECHNIQUES
DR. DEEPAK P

5. UNIT 5 STERILIZATION TECHNIQUES
Sterilization Definition
•Sterilizationreferstotheprocessofcompletely
eliminatingordestroyingallformsofmicrobiallife,
includingbacteria,viruses,fungi,andspores,froma
surface,object,substance,orenvironment.Theprimary
goalofsterilizationistoensurethepreventionofany
infectiousorpathogenicagentsfromsurvivingand
spreading.

6. •Therearevariousmethodsofsterilization,eachwithits
ownsetofapplicationsandadvantages.
•Common sterilizationtechniquesincludeheat-based
methodssuchasautoclaving(steamsterilization),dry
heat,andflaming;chemicalmethodsinvolvingtheuseof
disinfectantsandsterilizingagents;aswellasphysical
methodslikeradiation(ionizingornon-ionizing)and
filtration.

8. IMPORTANCE
•Sterilizationiscommonlyemployedinmedicaland
healthcaresettingstoensurethesafetyofsurgical
instruments,medicalequipment,andpharmaceutical
products.
•Itisalsoutilizedinlaboratories,foodprocessing,and
otherindustrieswheremaintainingasterileenvironment
iscriticaltopreventcontaminationandensureproduct
quality.

9. Microbial
culture

11. DISINFECTANT
•Adisinfectantisachemicalsubstanceorphysicalagent
thatisusedtodestroyorinhibitthegrowthof
microorganismsonsurfacesandobjects.
•Disinfectantsarespecificallydesignedtoeliminateor
reducethenumberofpathogens,includingbacteria,
viruses,fungi,andothermicroorganisms,toalevelthat
isconsideredsafeforpublichealth.

12. •Disinfectantsaredifferentfromsterilizingagents,as
theymaynotnecessarilyeliminatealltypesof
microorganisms,suchasbacterialspores.
•Theyarecommonlyusedinvarioussettings,including
hospitals,households,laboratories,andpublicspaces,
tocontrolandpreventthespreadofinfections.

14. Somecommontypesofdisinfectantsinclude:
•Alcohol-baseddisinfectants:theseoftencontain
ethanolorisopropylalcoholandareeffective
againstawiderangeofmicroorganisms.
•Quaternaryammoniumcompounds(quats):these
arecationicsurfactantswithdisinfectant
propertiesandarecommonlyfoundinhousehold
disinfectantproducts.

15. •Chlorine-baseddisinfectants:compounds like
bleach(sodiumhypochlorite)areeffective
disinfectantsandareoftenusedforcleaningand
sanitizingsurfaces.
•Phenolicdisinfectants:thesecontainphenolor
phenoliccompoundsandareeffectiveagainsta
varietyofmicroorganisms.
•Hydrogenperoxide:itcanbeusedasa
disinfectant,anditseffectivenessisenhancedin
higherconcentrations.Itbreaksdownintowater

16. ANTISEPTIC
•Anantisepticisasubstancethatisappliedto
livingtissues(suchasskinormucous
membranes)toreducetheriskofinfection,
sepsis,orputrefaction.
•Unlikedisinfectants,whichareusedoninanimate
objectsandsurfaces,antisepticsareintendedfor
useonlivingorganisms.

18. •Antisepticsarecommonlyusedtocleanand
disinfectwounds,cuts,andotherinjuriesto
preventthegrowthandspreadofmicroorganisms
thatcouldleadtoinfections.
•Theyarealsoappliedtoskinsurfacesbefore
medicalprocedures,suchasinjectionsorsurgery,
toreducetheriskofintroducingharmful
microorganisms.

19. Commontypesofantisepticsinclude:
•Iodine-basedantiseptics:suchaspovidone-
iodine,whichisusedinsolutions,ointments,or
swabs.
•Alcohol-basedantiseptics:typicallycontaining
ethanolorisopropylalcohol,commonlyusedfor
disinfectingskin.
•Hydrogenperoxide:usedasanantisepticfor

20. •Chlorhexidine:anantisepticcommonlyused
inhealthcaresettings,includingsurgical
handscrubs.
•Benzalkonium chloride:aquaternary
ammonium compound oftenusedin
antisepticwipesandsolutions.

21. Sanitizer
•Asanitizerisasubstanceorproductdesignedtoreduce
oreliminategerms,bacteria,andothermicroorganisms
onsurfacesandskin.Sanitizersarecommonlyusedin
situationswheresoapandwatermaynotbereadily
available,providingaconvenientandeffectivewayto
disinfecthandsandsurfaces.
•Therearedifferenttypesofsanitizers,andtheycanbe
categorizedintohandsanitizersandsurfacesanitizers.

23. •Handsanitizer:
•Alcohol-basedhandsanitizers:mosthandsanitizers
onthemarketcontainalcoholastheactiveingredient.
Common typesofalcoholusedincludeethanol,
isopropylalcohol,oracombinationofboth.
•Alcohol-basedhandsanitizersareeffectiveagainsta
broadspectrumofmicroorganismsandarecommonly
usedforpersonalhandhygiene.

24. •Handsanitizer:
•Non-alcoholhandsanitizers:somehand
sanitizersusealternativeactiveingredients,
suchasbenzalkoniumchloride,whichcanbe
effectiveagainstcertainmicrobes.Theseare
oftenusedinsituationswherealcohol-based
productsarenotsuitable,suchasin
environmentswherethereisariskoffire.

25. •Surfacesanitizer:
•Sprays,wipes,orliquidsolutions:theseare
designedtobeappliedtosurfacestodisinfect
andreducethemicrobialload.Surface
sanitizersmaycontainalcohol,hydrogen
peroxide,orotheractiveingredientsdepending
ontheformulation.

26. GERMICIDE
•Agermicideisatypeofsubstanceoragentthatis
specificallydesignedtokillorinhibitthegrowth
ofmicroorganisms,includingbacteria,viruses,
fungi,andotherpathogens.
•Germicidesareoftenusedtodisinfectsurfaces,
objects,andenvironmentstoreducetheriskof
infectionandthespreadofdiseases.

27. •Germicidescancomeinvariousformsand
types,andtheireffectivenessmayvary
basedonthespecificmicroorganisms
targeted,theconcentrationoftheactive
ingredients,andtheapplicationmethod.

28. •Chemicalgermicides:
•Disinfectants:thesearesubstancesusedon
surfacesandinanimateobjectstodestroyor
inhibitthegrowthofmicroorganisms.
Disinfectantsarecommonlyusedinhealthcare
settings,laboratories,andhouseholdsto
maintainahygienicenvironment.
Commontypesofgermicidesinclude:

29. •Chemicalgermicides:
•Antiseptics:asmentionedearlier,antiseptics
areatypeofgermicideusedonlivingtissuesto
preventinfections.Theyarecommonlyusedfor
woundcare,skindisinfection,andpre-surgical
procedures.

30. •Physicalgermicides:
•Ultraviolet(UV)light:certainwavelengthsofUV
lighthavegermicidalpropertiesandcanbe
usedtodisinfectair,water,andsurfaces.
•UV-Clightisparticularlyeffectiveindestroying
theDNAandRNAofmicroorganisms.

31. •Physicalgermicides:
•Heat:hightemperatures,suchasthose
achievedinautoclaves,canserveasaphysical
germicidebykillingmicroorganismsthrough
denaturationofproteinsandothercellular
structures.

32. •Germicidesplayacrucialroleinmaintaining
hygieneandpreventingthespreadof
infectiousdiseases.
•Thechoiceofaspecificgermicidedepends
ontheintendedapplication,thetypeof
microorganismstargeted,andotherfactors
suchassafetyand environmental
considerations.

33. MICROBICIDALAGENTS
•Microbicidalagentsaresubstancesoragentsthat
havetheabilitytokillordestroymicroorganisms,
includingbacteria,viruses,fungi,andothertypes
ofmicrobes.
•Theseagentsareusedtodisinfectsurfaces,
objects,andsubstances,aswellasinmedicaland
healthcaresettingstopreventthespreadof
infections.
•Theterm"microbicidal"isderivedfrom"microbe,"
referringtoamicroscopicorganism,and"cide,"
indicatingtheactofkilling.

34. Severaltypesofmicrobicidalagentsexist,andthey
canbeclassifiedbasedontheirmechanismof
actionorthespecificmicroorganismstheytarget.
•Antibiotics:thesearesubstancesthatcankillor
inhibitthegrowthofbacteria.Antibioticsare
commonlyusedinmedicinetotreatbacterial
infections.
•Antiviralagents:thesearesubstancesdesignedto
inhibitthereplicationofviruses.Antiviralagents
areusedtotreatviralinfectionsinvariousmedical
contexts.
•(Suchastenofovir,emtricitabine,lamivudine,abacavir,stavudine,

35. •Antifungalagents:thesesubstancesareeffective
againstfungiandareusedtotreatfungal
infections.
•Disinfectants:chemicalagents,suchas
quaternaryammonium compounds, chlorine-
basedcompounds,andalcohol,arecommonly
usedasdisinfectantstokillordeactivateabroad
spectrumofmicroorganismsonsurfaces.
Thefourmainclassesofantifungaldrugsare
thepolyenes,azoles,allylaminesandechinocandins.

36. •Antiseptics:thesearemicrobicidalagentsspecifically
usedonlivingtissues,suchastheskin,topreventor
treatinfections.Common antisepticsincludeiodine-
basedsolutions,alcohol-basedhandsanitizers,and
hydrogenperoxide.
•Sterilizingagents:agentssuchasethyleneoxide,steam
(autoclaving),andradiationareusedforsterilization,
whichgoesbeyondmicrobicidalactiontocompletely
eliminateallformsofmicrobiallife,includingspores.

37. MICROBIOSTATICAGENT
•Amicrobiostaticagentisasubstanceoragent
thatinhibitsthegrowthandreproductionof
microorganismswithoutnecessarilykillingthem.
•Unlikemicrobicidalagents,whichactivelykill
microorganisms,microbiostaticagentsarrestthe
growthandreproductionofbacteria,fungi,and
othermicrobes,essentiallyputtingthemina
stateofdormancy orpreventingfurther
multiplication.

38. Common examples of microbiostatic agents include:
•Antibiotics:manyantibioticsfunctionasmicrobiostaticagentsby
inhibitingthegrowthandreplicationofbacteria.Theyinterfere
withessentialcellularprocesses,suchasproteinsynthesisorcell
wallformation,preventingthebacteriafrommultiplying.
•Antifungalagents:certainantifungalmedicationscanactas
microbiostaticagentsbyinhibitingthegrowthoffungi.Theymay
interferewithfungalcellmembranesynthesisorothervital
cellularprocesses.

39. Common examples of microbiostatic agents include:
•Someantiviralmedications:certainantiviraldrugsmay
exhibitmicrobiostaticeffectsbypreventingthe
replicationofviruseswithinhostcells.
•Preservatives:inthecontextoffoodand
pharmaceuticals,some preservativesfunctionas
microbiostaticagentsbypreventingthegrowthof
bacteria,molds,andyeast.Theseagentshelpextendthe
shelflifeofproducts.

40. ANTIMICROBIAL AGENT
•Antimicrobialagentsaresubstancesthathavetheability
tokillorinhibitthegrowthofmicroorganisms.
•Thistermencompassesabroadrangeofagentsthatcan
targetvarioustypesofmicroorganisms,including
bacteria,viruses,fungi,andparasites.
•Antimicrobialagentsplayacrucialroleinmedicine,
publichealth,andvariousindustrieswherecontrolling
thegrowthofmicroorganismsisimportant.

41. •Antibiotics:thesearesubstancesthatspecificallytargetbacteria.
Antibioticscaninterferewithbacterialcellwallsynthesis,protein
synthesis,DNAreplication,orotheressentialprocesses,leadingto
thedeathorinhibitionofbacteria.
•Antiviralagents:thesesubstancestargetvirusesandaimtoinhibit
theirreplication.Antiviraldrugsmayactondifferentstagesofthe
virallifecycle,preventingviralattachment,entry,replication,or
release.
•Antifungalagents:theseagentsaredesignedtocombatfungal
infections.Theymaytargetfungalcellwalls,cellmembranes,or
interferewithfungalmetabolism.

42. •Antiparasiticagents:theseagentsareusedtotreatinfections
causedbyparasites,includingprotozoaandhelminths.
Antiparasiticdrugscantargetvariousstagesoftheparasitelife
cycle.
•Disinfectants:chemicalsubstancessuchasquaternaryammonium
compounds, chlorine-basedcompounds, andalcoholare
commonly usedasdisinfectantstokillordeactivate
microorganismsonsurfaces.
•Antiseptics:similartodisinfectants,antisepticsareusedonliving
tissuestopreventortreatinfections.Commonantisepticsinclude
iodine-basedsolutions,alcohol-basedhandsanitizers,and

43. •Silverandcoppercompounds:thesemetalsandtheir
compoundshaveantimicrobialpropertiesandareused
invariousapplications,includingwounddressingsand
medicaldevices.
•Phagetherapy:bacteriophages,orvirusesthatinfect
bacteria,canbeusedasatargetedapproachtotreat
bacterialinfections.