Show simple item record

Characterization, rational design and application of highly efficent raw starch degrading α-amylase from Bacillus licheniformis.

dc.contributor.advisorVujčić, Zoran
dc.contributor.otherBožić, Nataša
dc.contributor.otherGavrović-Jankulović, Marija
dc.creatorŠokarda Slavić, Marinela
dc.date.accessioned2018-02-26T13:48:37Z
dc.date.available2018-02-26T13:48:37Z
dc.date.available2020-07-03T10:15:31Z
dc.date.issued2017-11-03
dc.identifier.urihttp://eteze.bg.ac.rs/application/showtheses?thesesId=5585
dc.identifier.urihttp://nardus.mpn.gov.rs/handle/123456789/9170
dc.identifier.urihttps://fedorabg.bg.ac.rs/fedora/get/o:17082/bdef:Content/download
dc.identifier.urihttp://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=49840143
dc.description.abstractSloženi ugljeni hidrati kao što je skrob, od velikog su industrijskog značaja kako u oblastima bioenergije i bioprocesovanja, tako i u ljudskoj ishrani. Enzimi koji mogu direktno da hidrolizuju sirovi (nativni, granularni) skrob na temperaturama nižim od temperature geliranja privlače sve veći interes jer bi njihovom upotrebom mogao da se smanji utrošak velike količine energije u zagrevanju skroba prilikom geliranja, a time i pojeftini proces. Rekombinantna α-amilaza iz Bacillus licheniformis ATCC 9945a (BliAmy), efikasna u hidrolizi granularnog skroba ispod temperature geliranja, proizvedena je ekstracelularno korišćenjem Escherichia coli kao domaćina. Razvijeni su efikasni i reproduktivni procesi fermentacije sa ćelijama E. coli BL21 (DE3) i E. coli C43 (DE3) kroz dizajn medijuma za rast mikroorganizma i optimizaciju koraka u proizvodnji amilaze. Dobijene su velike količine BliAmy i to, u fermentaciji sa ćelijama E. coli BL21 (DE3) ukupna amilazna aktivnost od 250,5 IU mL-1 (0,7 g L-1 ), a sa ćelijama E. coli C43 (DE3) 500 IU mL−1 (1,2 g L−1). Primenjen je eksperimentalni dizajn u optimizaciji hidrolize skroba, prečišćavanju proteina i dobijanja bioetanola. Korišćenjem statističke metode odgovornih površina optimizovan je proces hidrolize koncentrovane suspenzije sirovog kukuruznog skroba. Pokazano je da je BliAmy veoma efikasna jer je hidrolizovala 91 % prilikom hidrolize 30 % - ne suspenzije skroba nakon 24 sata. Na osnovu promena u kristalnoj strukturi analiziranjem rezidualnog skroba koji zaostaje nakon hidrolize 30%-ne susupenzije nakon 5 i 24 sata pokazano je da kukuruzni skrob ima A-tip i Vh-tip kristaliniteta. Upoređivanjem difrakcionih intenziteta pikova kristalne strukture i SEM mikrografije nativnog i rezidualnog skroba može se zaključiti da se istom brzinom hidrolizuju i kristalni i amorfni regione u granulama skroba, što je u skladu sa načinom hidrolize skrobnih granula tzv. „granula po granula“...sr
dc.description.abstractComplex carbohydrates such as starch are of great industrial interest, especially in the areas of bioenergy and bioprocessing and increasingly in human nutrition. The importance of enzymes capable of direct hydrolysis of raw (native, granular) starch below the temperature of gelatinization has been well recognized due to the energy savings and the effective utilization of biomass, which reduces the overall cost of starch processing. Recombinant α-amylase from Bacillus licheniformis ATCC 9945a (BliAmy), highly efficient in raw starch hzdrolysis was produced extracellularly in Escherichia coli. An efficient and reproducible fermentation approach was developed with cells E. coli BL21 (DE3) and E. coli C43 (DE3) through the smart design of defined growth medium and optimization of process steps. Significant overexpression of BliAmy was achieved. Using E. coli BL21 (DE3) total of 250.5 IU mL-1 (0.7 g L-1 ) was obtained while using E. coli C43 (DE3) total of 500 IU mL−1 (1.2 g L−1) was achived. Experimental design was applied to optimize the hydrolysis of starch, protein purification and production of bioethanol. The hydrolysis of concentrated raw starch was optimized using response surface methodology. BliAmy was very effective, achieving the final hydrolysis degree of 91 % for the hydrolysis of 30 % starch suspension after 24 h. Cystalline structure of starch residues analysed by X-ray diffraction on the samples originating from 30 % starch suspensions after 5 and 24 h shown A-type and a Vh-type crystallinity of corn starch. Constant diffracted intensities and scattering background indicated that BliAmy most likely degraded both amorphous and crystalline areas at the same rates. This is in agreement with a granule by granule mode of attack and can be concluded from the SEM micrographies...en
dc.formatapplication/pdf
dc.languagesr
dc.publisherУниверзитет у Београду, Хемијски факултетsr
dc.rightsopenAccessen
dc.sourceУниверзитет у Београдуsr
dc.subjectα-amilazasr
dc.subjectα-amylaseen
dc.subjectraw starchen
dc.subjecthydrolysisen
dc.subjectbioethanolen
dc.subjectthe experimental designen
dc.subjectsurface binding sites (SBS)en
dc.subjectrational designen
dc.subjectsirovi skrobsr
dc.subjecthidrolizasr
dc.subjectbioetanolsr
dc.subjectdizajn eksperimentasr
dc.subjectmesto vezivanja za supstrat (SBS). racionalni dizajnsr
dc.titleKarakterizacija, racionalni dizajn i primena visokoefikasne α-amilaze iz Bacillus licheniformis za hidrolizu sirovog skrobasr
dc.title.alternativeCharacterization, rational design and application of highly efficent raw starch degrading α-amylase from Bacillus licheniformis.en
dc.typedoctoralThesis
dc.rights.licenseBY-ND
dcterms.abstractВујчић, Зоран; Божић, Наташа; Гавровић-Јанкуловић, Марија; Шокарда Славић, Маринела; Карактеризација, рационални дизајн и примена високоефикасне α-амилазе из Бациллус лицхениформис за хидролизу сировог скроба; Карактеризација, рационални дизајн и примена високоефикасне α-амилазе из Бациллус лицхениформис за хидролизу сировог скроба;
dc.identifier.fulltexthttp://nardus.mpn.gov.rs/bitstream/id/30102/Disertacija.pdf
dc.identifier.fulltexthttp://nardus.mpn.gov.rs/bitstream/id/30103/IzvestajKomisije17778.pdf


Files in this item

Thumbnail
Thumbnail

This item appears in the following Collection(s)

Show simple item record