This document provides information about Rajveer Atal's 12th class biology investigatory project on microbes. It begins with an acknowledgment and introduction on microbes. It then discusses various uses of microbes in areas like food, water treatment, energy production, chemical and enzyme production, and science. It also briefly mentions uses of microbes in warfare. The conclusion summarizes that microbes play an important role in ecology and various industries through functions like decomposition, and production of enzymes, antibiotics, fuels and more.

1. NAME –RAJVEER
ATAL
CLASS – XIIth
ROLL NO -

2. SUBJECT –
BIOLOGY
INVESTIGATORY
PROJECT
PRAGATI VIDYA
PEETH

3. Gwalior

5. Certificate

6. INDEX
S.No
.
Topic Pag
e

7. No.
1. Acknowledgemen
t
1
2. Introduction 2–3
3. Presentation 4-
4. Conclusion
5. Bibliography

8. ACHKNOWLEG
EMENT
I wouldliketo convey our sincere
gratitude toour Biology teacher
forletting us todothis project.I
would liketothank myfriendsfor
helpingmein thisproject and a

9. special thanks toMrs. Gunjan
Nigam (Biology teacher) for
guiding throughout the project.I
sincerely haveworked hard to
completethis project. I tried to
make thisproject asGood as
possible.Last butnot least I
would liketothank myclassmate
and parents fortheir valuable
suggestion about thisproject.

10. Submitted to: Mrs Gunjan
Nigam
INTRODUCTIO
N
Whataremicrobes?
Whataremicrobes? Amicroorganism or
microbe isamicroscopic organismthat

11. comprises eitherasinglecell (unicellular),cell
clusters, ormulticellular relativelycomplex
organisms.Thestudy ofmicroorganismsis
calledmicrobiology, asubject thatbeganwith
AntonvanLeeuwenhoek'sdiscoveryof
microorganismsin 1675,usingamicroscope
of hisowndesign.Microorganismsarevery
diverse;theyinclude bacteria,fungi,algae,
andprotozoa;microscopicplants(green
algae);andanimalssuch asrotifersand
planarians.Some microbiologistsalso include
viruses,butothersconsidertheseas
nonliving.Mostmicroorganismsare
unicellular(single-celled),but thisisnot
universal,sincesome multicellular organisms

12. aremicroscopic, whilesome unicellular
protistsandbacteria,likeThiomargarita
namibiensis,aremacroscopicandvisible to
thenakedeye.
Microorganismslive inall partsof the
biospherewherethereisliquid water,
including soil,hotsprings,on theoceanfloor,
highin theatmosphereanddeepinsiderocks
withintheEarth'scrust.Microorganismsare
criticaltonutrientrecyclingin ecosystemsas
theyactasdecomposers. Assome
microorganismscan fixnitrogen,theyarea
vitalpartof thenitrogencycle,andrecent
studiesindicatethatairbornemicrobesmay
play arole inprecipitationandweather.
Microbesarealsoexploitedby people in

13. biotechnology,bothin traditionalfoodand
beveragepreparation,andinmodern
technologiesbasedongeneticengineering.
However,pathogenicmicrobesareharmful,
since theyinvadeandgrowwithinother
organisms,causingdiseasesthatkillhumans,
otheranimalsandplants.Buttheyhavealot
of usestoo.Let’sdiscuss aboutsomeof them.
Alittledescription:
A littledescriptionMicroorganismsarevital
tohumansandtheenvironment,asthey
participatein theEarth'selementcyclessuch
asthecarbon cycle andnitrogencycle,aswell
asfulfilling othervitalrolesin virtually all
ecosystems,such asrecycling other

14. organisms'deadremainsandwasteproducts
throughdecomposition.Microbesalso have
animportantplace inmost higher-order
multicellular organismsassymbionts.Many
blame thefailure ofBiosphere2 onan
improperbalance ofmicrobes.
PRESENTATIO
N

15. Microbesarevery importantpartof ecology
themain orgeneralfunctionof microbestoor
environmentalwellfare istoworkas
decomposers. Microbeslikebacteriaand
fungiarealso usedinindustrialproduction of
enzymesandproteinsorsome antibiotics.
Some fungilikeyeastarealso usedinmaking
wineandotherindairy products.The
anotherusefulfunctionofmicrobe istostudy
theactionandmechanismsofgeneticdisease
asE.coli ismany timetakenasmodeltostudy
geneticdiseases.

16. Usesinfood:
Uses infood Microorganisms are used inbrewing,
winemaking, baking, pickling and other food-
making processes. They are also used to control
the fermentation process inthe production of
cultured dairy products such as yogurt and
cheese. The cultures also provide flavour and
aroma, and inhibit undesirable organisms.

17. Fermentation in food processing typically isthe
conversion ofcarbohydrates to alcohols and
carbon dioxide or organic acids using yeasts,
bacteria, or acombination thereof, under
anaerobic conditions. Fermentation in simple
terms is the chemical conversion of sugars into
ethanol. The science of fermentation is also
known as zymology, or zymurgy. Fermentation
usually implies that the action of microorganisms
is desirable, and the process isused to produce
alcoholic beverages such aswine, beer, and cider.
Fermentation is also employed inthe leavening of
bread (CO2 produced byyeast activity), and for
preservation techniques to produce lactic acidin
sour foods such as sauerkraut, dry sausages,
kimchi and yogurt, orvinegar (acetic acid)for use
in pickling foods.

18. Usesinwatertreatment:
Uses inwater treatment Specially-cultured
microbes are used in the biological treatment of
sewage and industrial waste effluent, a process
known as bioaugmentation. Bioaugmentation is
the introduction of a group of natural microbial
strains or a genetically engineered variant to treat
contaminated soil orwater. Usually the steps
involve studying the indigenous varieties present
in the location to determine if biostimulation is
possible. If the indigenous variety donot have the

19. metabolic capability to perform the remediation
process, exogenous varieties with such
sophisticated pathways are introduced.
Bioaugmentation is commonly used in municipal
wastewater treatment to restart activated sludge
bioreactors. Most cultures availablecontain a
research based consortium ofMicrobial cultures,
containing all necessary microorganisms ( B.
licheniformis ,B.thurengensis ,P.polymyxa ,B.
sterothemophilus ,Penicillium sp.,Aspergillus
sp.,Flavobacterium, Arthrobacter, Pseudomonas,
Streptomyces, Saccaromyces, Triphoderma, etc.).
Whereas activated sludge systems are generally
based on microorganisms likebacteria, protozoa,
nematodes, rotifers and fungi capable to degrade
biodegradable organic matter.

20. Usesinenergy:
Usesin energyMicrobesareusedin
fermentationtoproduce ethanol,andin

21. biogasreactorstoproduce methane.
Scientistsareresearchingtheuseof algaeto
produce liquidfuels, andbacteriatoconvert
variousforms ofagriculturalandurban waste
intousablefuels. Ethanolfermentation,also
referredtoasalcoholicfermentation,isa
biologicalprocess inwhichsugarssuchas
glucose,fructose,andsucrose areconverted
intocellularenergyandtherebyproduce
ethanolandcarbon dioxideasmetabolic
wasteproducts. Becauseyeastsperformthis
conversionin theabsenceof oxygen,ethanol
fermentationisclassifiedasanaerobic.
Ethanolfermentationoccursin the
production ofalcoholicbeveragesand
ethanolfuel,andintherisingof breaddough.
Cellulosic ethanolisabiofuelproduced from

22. wood,grasses,orthenon-ediblepartsof
plants.It isa typeofbiofuelproducedfrom
lignocellulose,a structuralmaterialthat
comprises much ofthemassof plants.
Lignocelluloseiscomposedmainly of
cellulose, hemicellulose andlignin.Corn
stover,switchgrass,miscanthus,woodchips
andtheby productsof lawnandtree
maintenancearesome ofthemorepopular
cellulosic materialsforethanolproduction.
Productionofethanolfromlignocellulose has
theadvantageofabundantanddiverseraw
materialcomparedtosourceslikecorn and
canesugars,butrequiresagreateramountof
processing tomakethesugarmonomers
availabletothemicroorganisms thatare

23. typically usedtoproduce ethanolby
fermentation.
Algaefuelisanalternativetofossilfuelthat
usesalgaeasitssource ofnaturaldeposits.
Severalcompaniesandgovernmentagencies
arefundingeffortstoreducecapitaland
operatingcostsandmakealgaefuel
production commercially viable.Harvested
algae,likefossilfuel,releaseCO 2 whenburnt
butunlikefossil fueltheCO2 istakenoutof
theatmosphereby thegrowingalgae.Highoil
prices, competingdemands betweenfoods

24. andotherbiofuelsources,andtheworldfood
crisis, haveignitedinterestin algaculture
(farmingalgae)formakingvegetableoil,
biodiesel,bioethanol,biogasoline,
biomethanol,biobutanolandotherbiofuels,
usinglandthatisnotsuitableforagriculture.
Amongalgalfuels'attractivecharacteristics:
theycan begrownwithminimal impacton
fresh waterresources,canbe producedusing
oceanandwastewater,andarebiodegradable

25. andrelativelyharmless totheenvironmentif
spilled. Algaecost moreperunitmass(asof
2010,foodgradealgaecosts~$5000/tonne),
duetohighcapitalandoperatingcosts,yetare
claimedtoyieldbetween10and100 times
more fuelperunitareathanothersecond-
generationbiofuelcrops. Onebiofuels
company hasclaimedthatalgaecanproduce
more oilin anareathesizeof atwocargarage
thana footballfieldof soybeans,because
almost theentirealgalorganismcan use
sunlighttoproduce lipids, oroil.TheUnited
StatesDepartmentofEnergyestimatesthatif
algaefuelreplacedallthepetroleumfuelin
theUnitedStates,itwouldrequire15,000
squaremiles (39,000km2 )whichisonly
0.42% of theU.S. map,orabouthalf of theland

26. areaofMaine.Thisislessthan1⁄7 theareaof
corn harvestedintheUnitedStatesin 2000.
However,theseclaims remainunrealized,
commercially. According totheheadofthe
AlgalBiomassOrganizationalgaefuelcan
reachprice paritywithoilin2018 if granted
production taxcredits.
Useinproductionofchemicals,enzymesetc.:
Use inproduction of chemicals,enzymesetc.
Manymicrobesareusedforcommercialand
industrialproductionof chemicals,enzymes
andotherbioactivemolecules. Examples of
organicacidproducedinclude Aceticacid:
Producedby thebacteriumAcetobacteraceti
andotheraceticacidbacteria(AAB)Acetic
acidbacteria(AAB)are bacteriathatderive

27. theirenergyfromtheoxidationofethanolto
aceticacidduring fermentation.Theyare
Gram-negative,aerobic,rod-shapedbacteria.
Theyarenottobeconfusedwiththegenus
Acetobacterium,whichareanaerobic
homoacetogenicfacultativeautotrophsand
can reducecarbon dioxidetoproduce acetic
acid,forexample,Acetobacteriumwoodii.
Butyricacid(butanoicacid):Producedbythe
bacteriumClostridiumbutyricum.

28. Clostridiumbutyricumisastrictly anaerobic
endospore-formingGram-positivebutyric
acidproducing bacillussubsistingby means
of fermentationusingan intracellularly
accumulatedamylopectin-likeα-polyglucan
(granulose)asasubstrate.It isuncommonly
reportedasahumanpathogenandwidely
usedasa probioticinAsia(particularly Japan).
C.butyricumisasoilinhabitantinvarious
partsoftheworld,hasbeenculturedfrom the
stoolofhealthychildren andadults,andis
common in souredmilk andcheeses.

29. Lacticacid:Lactobacillusandothers
commonly calledaslacticacidbacteria(LAB)
Thelacticacidbacteria(LAB)comprise a clade
of Gram-positive,low-GC,acid-tolerant,
generallynon-sporulating,non-respiringrod
orcocci thatareassociatedbytheircommon
metabolicandphysiologicalcharacteristics.
Thesebacteria,usually foundindecomposing
plantsandlacticproducts, produce lacticacid
asthemajormetabolicend-productof
carbohydratefermentation.Thistraithas,

30. throughouthistory,linkedLABwithfood
fermentations,asacidificationinhibitsthe
growthof spoilageagents.Proteinaceous
bacteriocinsareproducedby severalLAB
strainsandprovide anadditionalhurdle for
spoilageandpathogenicmicroorganisms.
Furthermore,lacticacidandothermetabolic
productscontributetotheorganolepticand
texturalprofile of afooditem.Theindustrial
importanceof theLABisfurtherevincedby
theirgenerallyrecognizedassafe (GRAS)
status,due totheirubiquitousappearancein
foodandtheircontributiontothehealthy
microflora of humanmucosal surfaces.
Citricacid:Producedby thefungus
AspergillusnigerAspergillus nigerisafungus

31. andoneofthemostcommon speciesofthe
genusAspergillus.It causesa diseasecalled
black mold oncertainfruitsandvegetables
such asgrapes,onions,andpeanuts,andisa
common contaminantoffood.Itis
ubiquitousinsoilandiscommonly reported
fromindoorenvironments,whereitsblack
coloniescanbe confusedwiththoseof
Stachybotrys(speciesof whichhavealso been
called"black mould").

32. Microbesareusedforpreparationof
bioactivemolecules andenzymes.
Streptokinaseproducedby thebacterium
Streptococcusandmodifiedby genetic
engineeringisusedasaclot busterfor
removingclotsfromthebloodvesselsof
patientswhohaveundergonemyocardial
infarctionsleadingtoheartattack.

33. Cyclosporin Aisabioactivemolecule usedas
animmunosuppressive agentinorgan
transplantationStainsproducedby theyeast
Monascuspurpureus iscommercialisedas
bloodcholesterolloweringagentswhichacts
by competitivelyinhibitingtheenzyme
responsible forsynthesisof cholesterol.
Usesinscience:
Usesin scienceMicrobesarealsoessential
toolsinbiotechnology,biochemistry,
genetics,andmolecular biology.Theyeasts(
Saccharomycescerevisiae) andfission yeast(
Schizosaccharomycespombe )areimportant
modelorganismsinscience,since theyare
simple eukaryotesthatcanbegrownrapidly
inlargenumbers andareeasily manipulated.

34. Theyareparticularly valuable ingenetics,
genomicsandproteomics.Microbescan be
harnessedforusessuch ascreatingsteroids
andtreatingskindiseases.Scientistsarealso
consideringusingmicrobes forliving fuel
cells, andasa solutionforpollution.
Usesinwarfare:
Usesin warfareIn theMiddle Ages,diseased
corpseswerethrownintocastlesduring
siegesusingcatapultsorothersiegeengines.
Individualsnearthecorpseswereexposedto
thedeadly pathogenandwerelikely tospread
thatpathogentoothers.Biologicalwarfare
(alsoknownasgermwarfare)istheuseof
biologicaltoxinsorinfectiousagentssuch as
bacteria,viruses,andfungiwithintenttokill

35. orincapacitatehumans,animalsorplantsas
anactof war.
Biologicalweapons(oftentermed"bio-
weapons"or"bio-agents")areliving
organismsorreplicatingentities(viruses)that
reproduce orreplicatewithintheirhost
victims.Entomological(insect)warfareisalso

36. consideredatypeof biologicalwarfare.
Biologicalweaponsmaybe employedin
variouswaystogainastrategicortactical
advantageoveranadversary,eitherby threats
orby actualdeployments.Likesome ofthe
chemicalweapons,biologicalweaponsmay
also beusefulasareadenialweapons.These
agentsmay belethalornon-lethal,andmay be
targetedagainstasingleindividual,agroupof
people,orevenanentirepopulation.They
may bedeveloped,acquired,stockpiledor
deployedby nationstatesorby non-national
groups.In thelattercase,orif anation-state
usesitclandestinely,itmay also beconsidered
bioterrorism.

37. Importanceinhumanhealth:
Importance inhumanhealthMicroorganisms
can formanendosymbioticrelationshipwith
other,largerorganisms.Forexample,the
bacteriathatlive withinthehuman digestive
systemcontributetogutimmunity,
synthesisevitaminssuchasfolicacidand
biotin,andfermentcomplex indigestible
carbohydrates.

38. Thehumanmicrobiome (orhuman
microbiota)istheaggregateof
microorganismsthatreside onthesurface
andindeeplayersof skin,in thesaliva andoral
mucosa,in theconjunctiva,andin the
gastrointestinaltracts.Theyinclude bacteria,
fungi,and archaea.Some of theseorganisms
performtasksthatareusefulforthehuman
host.However,themajorityhavenoknown
beneficialorharmfuleffect.Thosethatare
expectedtobepresent,andthatundernormal
circumstancesdo notcausedisease,but
insteadparticipateinmaintaininghealth,are
deemedmembers of thenormalflora .
Thoughwidely knownas"microflora", thisis,
intechnicalterms,a misnomer,since the
wordroot"flora"pertainstoplants, andbiota

39. referstothetotalcollectionof organismsin a
particularecosystem.Recently,themore
appropriateterm"microbiota"isapplied,
thoughitsuse hasnoteclipsedtheentrenched
useandrecognitionof"flora" withregardto
bacteriaandothermicroorganisms. Both
termsarebeingusedin different literature.
Studiesin 2009 questionedwhetherthe
decline inbiota(includingmicrofauna)asa
result ofhuman interventionmightimpede
humanhealth
Importanceinecology:
Importance inecologyMicrobesarecritical
totheprocesses ofdecomposition requiredto
cycle nitrogenandotherelementsback tothe

40. naturalworld.Decomposition(orrotting) is
theprocess by whichorganicsubstancesare
brokendownintosimpler formsof matter.
Theprocessisessentialforrecyclingthefinite
matterthatoccupiesphysical spacein the
biome.Bodiesof livingorganismsbeginto
decompose shortly afterdeath.Althoughno
twoorganismsdecompose in thesame way,
theyall undergothesame sequentialstagesof
decomposition.
Thesciencewhichstudiesdecomposition is
generallyreferredtoastaphonomyfromthe
Greekwordtaphos,meaningtomb.One can
differentiateabioticfrombiotic
decomposition(biodegradation).Theformer
means"degradationofa substanceby
chemicalorphysicalprocesses,eghydrolysis).

41. Thelatteronemeans"themetabolic
breakdownof materialsintosimpler
componentsby livingorganisms",typically
by microorganisms.
Hygiene:
HygieneHygieneistheavoidanceof infection
orfoodspoiling by eliminating
microorganismsfromthesurroundings.As
microorganisms, inparticularbacteria,are

42. foundvirtuallyeverywhere,thelevelsof
harmfulmicroorganismscan bereducedto
acceptablelevels. However,insome cases,itis
requiredthatanobjectorsubstancebe
completely sterile,i.e.devoidofall living
entitiesandviruses.A goodexample ofthisis
ahypodermicneedle.In foodpreparation
microorganismsarereducedby preservation
methods(such astheadditionofvinegar),
clean utensilsusedinpreparation,short
storageperiods, orby cooltemperatures.If
complete sterilityisneeded,thetwomost
common methodsareirradiationandtheuse
of anautoclave,whichresembles apressure
cooker.

43. Thereareseveralmethodsforinvestigating
thelevelof hygieneinasample offood,
drinkingwater,equipment,etc.Water
samples canbe filtratedthroughanextremely
finefilter.Thisfilteristhenplacedina
nutrientmedium. Microorganismsonthe
filterthengrowtoformavisible colony.
Harmful microorganismscanbe detectedin
foodby placingasample ina nutrientbroth
designedtoenrichtheorganismsin question.
Variousmethods,such asselectivemedia or
PCR,can thenbe usedfordetection.The
hygieneofhardsurfaces,such ascooking
pots,can betestedby touchingthemwith a
solidpieceof nutrientmediumandthen
allowingthemicroorganismstogrowon it.
Therearenoconditionswhereall

44. microorganismswouldgrow,andtherefore
oftenseveraldifferentmethodsareneeded.
Forexample,afoodsample mightbe analyzed
onthreedifferentnutrientmediumsdesigned
toindicatethepresenceof "total"bacteria
(conditionswheremany,butnotall, bacteria
grow),molds (conditionswherethegrowth
of bacteriaispreventedby,e.g.,antibiotics)
andcoliformbacteria(theseindicateasewage
contamination).