细菌发酵L乳酸的研究(3)
发布时间:2021-06-06
发布时间:2021-06-06
细菌发酵L乳酸的研究
自{『菌发酵L(+)一乳酸的研究
Abstract
A。bstract
Afterscreening,astereoisometricallypureL(+)一lacticacidproducingstrainS3wasisolated.Itwaspreliminaryidentified
as
Lactobacillussp.Aftermultiplemutagenesis
on
(UV.,NTG,LiCIandDES)andscreeningwiththemethodbased
analysis
itspathway
whose
andmetabolicregulation,strainM7
was
successfullyobtained
productivityofL(+)-lacticacidWasimprovedby30%.Auxotrophdeterminationshowedthatitwasaminoaciddeficient.TheoptimumconditionfermentNionrTwo—level
was
andmediaforM7
design
investigated
withthe
application
ofPlacea—Burman
design)andBox—Behnkendesign(ResponseSurfaceAnalysis)wi也the
helpofSAS(Statistical
Analysis
System)software,theyieldincreasedby
15%.The
kineticmodelofbatchfermentationWasprimarilyestablished.Undertheoptimumlevel
determined
bythismethod,afterfermentationfor72hours,aproductivityof
92-100g/LL(+)一lacticacid
Can
be
achieved.Theanion—exchange
resinD301Gwas
improvetheIn
selectedtoseparatethelacticacidfrom
Situ
fermentationbroth.Inorderto
ProductRemovaltechniquewith
to
ionexchangeresinwhichalleviatedthe
inhibition
bacteriagrowth
as
wellasproductformation,extractive
fermentation
usingimmobilizedcellinCa2+.alginategelWasalsostudied.
Keywords:lacticacidbacteria,L(+) lacticacid,multiplemutagenesis;mutation,
Placer burmandesign,ResponseSurfaceAnalysis,immobilizedcell,InSituProductRemoval