Immobilization of saccharomyces cerevisiae in novel hydrogels based on hybrid networks of poly(ethylene oxide), alginate and chitosan for ethanol production

Ružica Jovanović-Malinovska, Maja Cvetkovska, Slobodanka Kuzmanova, Christo Tsvetanov, Eleonora Winkelhausen


Hydrogel matrices were designed as hybrid networks of poly(ethylene oxide) (PEO) with natural polymers,
alginate or chitosan by UV irradiation. The networks were formulated in the single-stage procedure in
which the alginate or chitosan were added to the crosslinking reaction solution of PEO, and two-stage procedure,
with additional chemical crosslinking of alginate or chitosan. Double-layer hydrogels composed of PEO
hydrogel core with entrapped cells and outer natural hydrogel layer were also synthesized. The hydrogels were
characterized by gel fraction yield and degree of equilibrium swelling as well as by rheological measurements.
The production of ethanol by immobilized Saccharomyces cerevisiae was used to test the suitability of the synthesized
hybrid hydrogels to serve as carriers for cell immobilization. The presence of cells affected the mechanical
properties and the structure of the polymer networks. The best system for immobilization was found to be
the PEO/alginate/Ca, which exhibited high mechanical strength (G′, 830; GF, 93; ESH2O, 15) without affecting
the metabolic functions of the cells. The maximum ethanol yield was 0.42 g/g corresponding to 82 % of the
theoretical yield.


hybrid networks; poly(ethylene oxide); alginate; chitosan; cell immobilization; ethanol production

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Y. Lin, S. Tanaka, Ethanol fermentation from biomass

resources: Current state and prospects, Appl.

Microbiol. Biotechnol., 69, 627–642 (2006).

A. J. Ragauskas, C. K. Williams, B. H. Davison,

G. Britovsek, J. Cairney, C. A. Eckert, W. J. Frecerick

Jr., J. P. Hallett, D. J. Leak, C. L. Liotta, J.

R. Mielenz, R. Murphy, R. Templer, T. Tschaplinski,

The path forward for biofuels and biomaterials,

Science, 311, 484–489 (2006).

F. O. Licht, World ethanol production 2007 to hit

new record, World Ethanol and Biofuels Report,

, at Accessed


V. I. Lozinsky, Polymeric cryogels as a new family

of macroporous and supermacroporous materials

for biotechnological purposes, Russ. Chem. Bull.,

Int. Ed., 57, (5) 1015–1032 (2008).

O. Smidsrød, G. Skjåk-Bræk, Alginate as immobilisation

matrix for cells, Tibtech, 8, 71–78 (1990).

K. V. Harish Prashanth, R. N. Tharanthan, Chitin/

chitosan: modifications and their unlimited application

potential – an overview, Trends Food Sci.

Tech., 18, 117–131 (2007).

M. Liouni, P. Drichoutis, E.T. Nerantiz, Studies

of the mechanical properties and the fermentation

behaviour of double-layer alginate-chitosan

beads, using Saccharomyces cerevisiae entrapped

cells, World J. Microbiol. Biotechnol., 24, 281–288


H. Y. Kawaguti, E. M. Celestino, A. L. L. Moraes,

D. K. Yim, L. K. Yamamoto, H. H. Sato, Characterization

of a glucosyltransferase from Erwinia

sp. D12 and the conversion of sucrose into isomaltulose

by immobilised cells, Biochem. Eng. J.,

, 211–217 (2010).

Q. Wen-tao, Y. Wei-ting, X. Yu-bing, M. Xiaojun,

Optimization of Saccharomyces cerevisiae culture

in alginate–chitosan–alginate microcapsule, Biochem.

Eng. J., 25, 151–157 (2005).

A. Bartowiak, S. Lisiecki, G. Orive, J. L. Pedraz,

The effect of selected parameters of formation on

properties of alginate/Ca2+/oligochitosan capsules,

J. Chem. Tech. Biotech., 81, 511–518 (2006).

E. Winkelhausen, R. Jovanović-Malinovska, S.

Kuzmanova, M. Cvetkovska, Ch. Tsvetanov, Hydrogels

based on u.v.-crosslinked poly(ethylene

oxide) – matrices for immobilisation of Candida

boidinii cells for xylitol production, World J Microbiol.,

Biotechnol. 10, (24) 2035–2043 (2008).

E. Veličkova, E. Winkelhausen, S. Kuzmanova,

M. Cvetkovska, Ch. Tsvetanov, Hydroxyethylcellulose

cryogels used for entrapment of Saccharomyces

cerevisiae cells, React. Funct. Polym., 69,

–693 (2009).

P. Petrov, E. Petrova, Ch. B. Tsvetanov, UV-assisted

synthesis of super-macroporous polymer hydrogels,

Polymer 20, 1118–1123 (2009).

M. Doytcheva, D. Dotcheva, R. Stamenova, A.

Orahovats, Ch. Tsvetanov, J. Leder, Ultraviolet-induced

crosslinking of solid poly(ethylene oxide),

J. Appl. Polym., Sci. 64, 2297–2307 (1997).

S. H. Emami, R. Salovey, Crosslinked poly(


hydrogels, J. Appl. Polymer Sci.,

, 1451–1455 (2003).

P. Eiselt, K. Y. Lee, D. J. Mooney, Rigidity of twocomponent

hydrogels prepared from alginate and

poly(ethylene glycol)-diamines. Macromolecules,

, 5561–5566 (1999).

J. L. Stringer, N. A. Peppas, Diffusion of small

molecular weight drugs in radiation-crosslinked

poly(ethylene oxide) hydrogels. J. Control Release.,

, 195–202 (1996).

M. B. Mellott, K. Searcy, M. V. Pishko, Release

of protein from highly cross-linked hydrogels of

poly(ethylene glycol) diacrylate fabricated by UV

polymerization, Biomaterials, 22, 929–941 (2001).

V. I. Lozinsky, A. L. Zubov, E. F. Titova, Poly(vinyl

alcohol) cryogels employed as matrices for cell

immobilisation. 2. Entrapped cells resemble porous

fillers in their effects on the properties of

PVA-cryogel carrier, Enz. Microb. Technol., 20,

(3) 182–190 (1997).

V. Manojlovic, J. Djonlagić, B. Obradović, V.

Nedović, B. Bugarski, Investigation of cell immobilization

in alginate: rheological and electrostatic

extrusion studies. J. Chem. Tech. Biotech., 81,

–510 (2006).

T. S. Khaw, Y. Katakura, K. Ninomiya, C. Moukamnerd,

A. Kondo, M. Ueda, S. Shioya, Enhancement

of ethanol production by promoting surface

contact between starch granules and arming yeast

in direct ethanol fermentation, J. Biosci. Bioeng.,

(1) 95–97 (2007).

J. Berger, M. Reist, J. M. Mayer, O. Felt, N. A.

Peppas, R. Gurny, Structure and interactions in covalently

and ionically crosslinked chitosan hydrogels

for biomedical applications, Eur. J. Pharm.

Biopharm., 57, 19–34 (2004).



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