Project properties
Title Plastic biodegradation What if microorganismes could do the job?
Group Soil Physics and Land Management group
Project type thesis
Credits 24-39
Supervisor(s) Davi Munhoz and Ke Meng
Examiner(s) Coen Ritsema
Contact info
Begin date 2022/09/05
End date
Description Project description

Problemcontext
Plasticsandmicroplasticsarecurrentlyenvironmentalissuesinagriculturalsoils.Althoughsomeplasticsaresoldasbiodegradable,researchersarestillfindingmicroplasticsandplasticscontainingpolybutyleneadipateterephthalate(PBAT)andpolylacticacid(PLA)inagriculturalsoilsseveralyearsaftertheirapplication.Low-densitypolyethylene(LDPE)plasticsarealsofoundinhighconcentrationsinthisenvironment.Previousresearchhasshownthepotentialofmicroorganismsdwellingintheearthworm`sguttoinitiatethedegradationofthesepolymers.Nevertheless,littleisknownabouttheplasticdegradationmechanismsandratesonceexposedtotheisolatedmicroorganisms.Inthisstudy,thesixcandidatestrainshavealreadybeenisolated,andweareinterestedinevaluatingthepotentialofthesemicroorganismstodegradedifferenttypesofplastics
ResearchObjective/Question
Aretheselectedandisolatedmicroorganismsfromtheearthworms`gutabletodegradePBAT-,PLA-,andUV-agedLDPEplastics?Ifyes,whichstrainsaremorepronetoattackwhichplastics?
What is expected from the student (type of research)
Wearelookingforanenthusiasticstudentwillingtoparticipateintheentireprocess,fromdesigningandsettinguptheexperimentwithtargetedmicroorganismstodataanalysisandwriting.
Basicmicrobiologylaboratoryskillsareaplus,aswellasbasicknowledgeofbiologyandbiochemistry.
Project details
Group:Soil Physics and Land Management group
Project type:Eitherthesis or internship
Startingdate: Flexible
End date:6 monthsafterthestartingdate
Usedskills:
Requirements:
Contact
Supervisor(s):Davi Munhoz andKe Meng
Examiner: Violette Geissen, Esperanza Huerta Lwanga, andPaula Harkes
Contact details:davi.munhoz@wur.nl& ke.meng@wur.nl
Microorganisms
LDPE
PLA
PBAT
Treatment A
Treatment B
Treatment C
BIO-BLEND

Beforestarting
•
ASKpaulaaboutgrowthcurve
•
Pilottest
–
Definecellconcentration(CASECounterorNanoDrop(OD600)–beforeinoculation
–
STICKTOONEODvalueoronecasecountermethodology
–
DEFINEAProtocolforcellcounting.
Months
Planned activity
1
-Literaturereview
-Settinguptheexperiment(Labwork)
-Inoculatemicroorganismsintotubeswithliquidmediaandplateswithagar
-Placetheplasticsintothetubesandplates
Atthisstage,theywilllearnmicrobiologylabskillsandunderstandingtheexperimentaldesign.Theywillalsogetfreshknowledgefromourpreviousexperimentsandknowledge.
2
Startwritingthemethodology
Maintainingtheexperimentifneeded
LearnhowtouseATR-FTIRandFTIR(Training)
3
Firstsamplingpoint
Firstanalyzes(WeightLoss,andATR-FTIR)
Visualinspectiontoassessfurthertechniquesthatmaybeneeded
4
WriteIntroduction
Dataanalysisforthefirstsamplingpoint
5-6
WriteIntroduction+Results
Second sampling point
ATR-FTIR, weight loss and Data analysis
Writing
BackUpPlan
Mostlikelythereisnoneed,butifthestrainsdonotattacktheplastics,weknowtreatmentsthatwoulddoso(atleastforPLA
Used skills
Requirements