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Talebnia, Farid
Publications (8 of 8) Show all publications
Westman, J. O., Talebnia, F., Franzén, C. J. & Taherzadeh, M. J. (2010). Together we are strong! Inhibitor tolerance conferred by good neighbors?. In: : . Paper presented at Industrial Systems Biology: Sustainable Production of Fuels and Chemicals, Gothenburg, Sweden, August 2010 and XVIII International Conference on Bioencapsulation, Porto, Portugal, October 2010.
Open this publication in new window or tab >>Together we are strong! Inhibitor tolerance conferred by good neighbors?
2010 (English)Conference paper, Poster (with or without abstract) (Other academic)
Keywords
yeast, flocculation, encapsulation, ethanol, inhibitors, Energi och material
National Category
Other Industrial Biotechnology
Identifiers
urn:nbn:se:hb:diva-6395 (URN)2320/6936 (Local ID)2320/6936 (Archive number)2320/6936 (OAI)
Conference
Industrial Systems Biology: Sustainable Production of Fuels and Chemicals, Gothenburg, Sweden, August 2010 and XVIII International Conference on Bioencapsulation, Porto, Portugal, October 2010
Available from: 2015-12-22 Created: 2015-12-22 Last updated: 2016-11-18Bibliographically approved
Pourbafrani, M., Talebnia, F. & Taherzadeh, M. (2009). Production of Bioethanol from Citrus Wastes by Encapsulated Yeast. In: Proceeding ISWA/APESB 2009 World Congress, Lissabon: . Paper presented at WTERT ISWA/APESB WORLD CONGRESS:Turning Waste into Ideas, Lisbon, October 12-15, 2009.. Proceeding ISWA/APESB 2009 World Congress
Open this publication in new window or tab >>Production of Bioethanol from Citrus Wastes by Encapsulated Yeast
2009 (English)In: Proceeding ISWA/APESB 2009 World Congress, Lissabon, Proceeding ISWA/APESB 2009 World Congress , 2009Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
Proceeding ISWA/APESB 2009 World Congress, 2009
Keywords
ethanol, citrus waste, encapsulation, baker's yeast, saccharomyces cerevisiae, Energi och material
National Category
Other Industrial Biotechnology
Identifiers
urn:nbn:se:hb:diva-6220 (URN)2320/5591 (Local ID)2320/5591 (Archive number)2320/5591 (OAI)
Conference
WTERT ISWA/APESB WORLD CONGRESS:Turning Waste into Ideas, Lisbon, October 12-15, 2009.
Available from: 2015-12-22 Created: 2015-12-22 Last updated: 2017-01-25Bibliographically approved
Teghammar, A., Talebnia, F., Sárvári Horváth, I. & Taherzadeh, M. (2008). Biogas or ethanol from paper tube residuals?. In: (Ed.), Proceeding 2nd International Simposium on Energy from Biomass and Waste, 17-20 Nov., Venice, Italy: .
Open this publication in new window or tab >>Biogas or ethanol from paper tube residuals?
2008 (English)In: Proceeding 2nd International Simposium on Energy from Biomass and Waste, 17-20 Nov., Venice, Italy, 2008Conference paper, Published paper (Refereed)
Keywords
Energi och material
National Category
Engineering and Technology
Identifiers
urn:nbn:se:hb:diva-6075 (URN)2320/4509 (Local ID)2320/4509 (Archive number)2320/4509 (OAI)
Available from: 2015-12-22 Created: 2015-12-22 Last updated: 2016-03-03
Talebnia, F. (2008). Ethanol Production from Cellulosic Biomass by Encapsulated Saccharomyces cerevisiae. (Doctoral dissertation). Chalmers University of Technology, Dep. of Chemical and Biological Engineering
Open this publication in new window or tab >>Ethanol Production from Cellulosic Biomass by Encapsulated Saccharomyces cerevisiae
2008 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Unstable oil markets with rising environmental concerns have revived widespread interest in production of fuel ethanol from renewable materials. Cellulosic materials are abundant and prominent feedstocks for cheap ethanol production. However, due to recalcitrant structure of these materials, pretreatment is a prerequisite. Depending on the biomass, pretreatment and hydrolysis conditions, a number of degradation products and/or toxic components may be released that show strong inhibitory effects on the fermenting microorganisms. This thesis deals with application of encapsulation technology to ferment the highly toxic hydrolyzates without further pretreatment. Free cells could not tolerate presence of 5 g/l furfural in defined medium, and inhibitors in wood and peel hydrolyzates in batch mode of operation and fermentation failed. Continuous cultivation of wood hydrolyzate was only successful at 0.1 h−1 and the majority of cells lost their viability after 5 retention times. Encapsulated cell system could successfully ferment the synthetic medium containing 5 g/l furfural during sequential batch cultivations with ethanol yield of 0.41-0.42 g/g. Cultivation of undetoxified hydrolyzates was also carried out, where glucose and mannose were converted within 10 h without significant lag phase. However, a gradual decrease in cell activity was observed in sequential batches. Continuous cultivation was more successful, and wood hydrolyzate was fermented to ethanol by encapsulated S. cerevisiae at dilution rates up to 0.5 h−1. More than 75% of the encapsulated cells were viable in the worst conditions. Ethanol was produced with yield 0.44 g/g and specific productivity 0.14–0.17 g/g•h at all dilution rates. Contrary to wood hydrolyzate, where there is no preference for permeation of sugars or inhibitors through the capsules’ membrane, encapsulation technology was applied to eliminate inhibition of limonene in fermentation of orange wastes to ethanol. The capsules’ membrane, of hydrophilic nature, is practically impermeable to hydrophobic compounds such as limonene while allowing penetration of nutrients and products. While presence of 0.1% v/v limonene in the medium results in strong inhibition or even failure of cultivation with free cells, using this technique allowed fermentation of a medium containing 1.5% v/v limonene. The impact of encapsulation on the anaerobic growth pattern, morphological and physiological changes of S. cerevisiae over long-term application was investigated. The growth rate, total RNA and protein content of the encapsulated cells decreased gradually over repeated batch cultivations, while stored carbohydrates content increased. Within 20 batch cultivations, total RNA and protein content of encapsulated cells decreased by 39% and 24%, whereas glycogen and trehalose content increased by factors of 4.5 and 4, respectively.

Place, publisher, year, edition, pages
Chalmers University of Technology, Dep. of Chemical and Biological Engineering, 2008
Series
Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie, ISSN 0346-718X ; 2778
Keywords
encapsulated cells, ethanol, s.cerevisiae, dilute-acid hydrolyzate, in situ detoxification, furfural, orange peels, experimental design, immobilization, limonene
National Category
Chemical Engineering
Identifiers
urn:nbn:se:hb:diva-3470 (URN)2320/3525 (Local ID)978-91-7385-097-1 (ISBN)2320/3525 (Archive number)2320/3525 (OAI)
Note

Akademisk avhandling som för avläggande av teknologie doktorsexamen vid Chalmers tekniska högskola försvaras vid offentlig disputation den 18 april 2008.

Available from: 2015-12-04 Created: 2015-12-04 Last updated: 2016-08-19Bibliographically approved
Talebnia, F., Pourbafrani, M., Taherzadeh, M. J. & Lundin, M. (2008). Optimization study of citrus wastes Saccharification by dilute acid hydrolysis. BioResources, 3(1), 108-122
Open this publication in new window or tab >>Optimization study of citrus wastes Saccharification by dilute acid hydrolysis
2008 (English)In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 3, no 1, p. 108-122Article in journal (Refereed) Published
Abstract [en]

Optimization study of citrus wastes Saccharification by dilute acid hydrolysis

Abstract [en]

Optimization study of citrus wastes Saccharification by dilute acid hydrolysis

Abstract [en]

The effects of time, acid concentration, temperature and solid concentration on dilute-acid hydrolysis of orange peels were investigated. A central composite rotatable experimental design (CCRD) was applied to study the individual effects of these hydrolysis factors and also their interdependence effects. The enzymatic hydrolysis of the peels by cellulase, beta-glucosidase, and pectinase enzymes resulted in 72% dissolution of the peels, including 18.7% galacturonic acid and 53.3% of a total of glucose, fructose, galactose, and arabinose. Dilute-acid hydrolysis up to 210 C was not able to hydrolyze pectin to galacturonic acid. However, the sugar polymers were hydrolyzed at relatively low temperature. The optimum results were obtained at 116 degrees C, 0.5% sulfuric acid concentration, 6% solid fraction, and 12.9 min retention time. Under these conditions, the total sugars obtained at 41.8% dry peels and 2.6% of total hexose sugars were further degraded to hydroxymethylfurfural (HMF). No furfural was detected through these experiments from decomposition of pentoses.

Place, publisher, year, edition, pages
North Carolina State University, 2008
Keywords
orange peels, dilute-acid hydrolysis, experimental design, suger optimization, Energi och material
National Category
Other Industrial Biotechnology
Identifiers
urn:nbn:se:hb:diva-2410 (URN)2320/3559 (Local ID)2320/3559 (Archive number)2320/3559 (OAI)
Available from: 2015-11-13 Created: 2015-11-13 Last updated: 2017-12-01Bibliographically approved
Talebnia, F. & Taherzadeh, M. (2007). Fermentability Improvement of Dilute-acid Hydrolyzate and High Ethanol Production Rate by Encapsulated S. cerevisiae. In: : . Paper presented at 29th Symp. on Biotechnology for Fuels and Chemicals, April 29 - May 2, 2007, Denver, CO, USA.
Open this publication in new window or tab >>Fermentability Improvement of Dilute-acid Hydrolyzate and High Ethanol Production Rate by Encapsulated S. cerevisiae
2007 (English)Conference paper, Published paper (Refereed)
Keywords
Energi och material
National Category
Industrial Biotechnology
Identifiers
urn:nbn:se:hb:diva-5769 (URN)2320/2964 (Local ID)2320/2964 (Archive number)2320/2964 (OAI)
Conference
29th Symp. on Biotechnology for Fuels and Chemicals, April 29 - May 2, 2007, Denver, CO, USA
Available from: 2015-12-22 Created: 2015-12-22 Last updated: 2016-11-18Bibliographically approved
Talebnia, F. & Taherzadeh, M. J. (2007). Physiological and Morphological Study of Encapsulated Saccharomyces cerevisiae. Enzyme and microbial technology, 41(6-7), 683
Open this publication in new window or tab >>Physiological and Morphological Study of Encapsulated Saccharomyces cerevisiae
2007 (English)In: Enzyme and microbial technology, ISSN 0141-0229, E-ISSN 1879-0909, Vol. 41, no 6-7, p. 683-Article in journal (Refereed) Published
Abstract [en]

The impact of encapsulation on the anaerobic growth pattern of S. cerevisiae CBS 8066 in a defined synthetic medium over 20 consecutive batch cultivations was investigated. In this period, the ethanol yield increased from 0.43 to 0.46 g/g, while the biomass and glycerol yields decreased by 58 and 23%, respectively. The growth rate of the encapsulated cells in the first batch was 0.13 h-1, but decreased gradually to 0.01 h-1 within the 20 sequential batch cultivations. Total RNA content of these yeast cells decreased by 39% from 90.3 to 55 mg/g, while the total protein content decreased 24% from 460 to 350 mg/g. On the other hand, the stored carbohydrates, i.e. glycogen and trehalose content, increased by factors of 4 and 4.5 within 20 batch cultivations, respectively. Higher biomass concentrations inside capsules led to a lower glucose diffusion rate through the membrane, and volumetric mass transfer coefficient for glucose was drastically decreased from 6.28 to 1.24 (cm3/min) by continuing the experiments. Most of the encapsulated yeast existed in the form of single and non-budding cells after long-term application.

Place, publisher, year, edition, pages
Elsevier Inc., 2007
Keywords
Energi och material
National Category
Chemical Engineering
Identifiers
urn:nbn:se:hb:diva-2276 (URN)10.1016/j.enzmictec.2007.05.020 (DOI)2320/2901 (Local ID)2320/2901 (Archive number)2320/2901 (OAI)
Available from: 2015-11-13 Created: 2015-11-13 Last updated: 2017-12-01Bibliographically approved
Pourbafrani, M., Talebnia, F., Niklasson, C. & Taherzadeh, M. (2007). Protective Effect of Encapsulation in Fermentation of Limonene-contained Media and Orange Peel Hydrolyzate. International Journal of Molecular Sciences, 8(8), 777-787
Open this publication in new window or tab >>Protective Effect of Encapsulation in Fermentation of Limonene-contained Media and Orange Peel Hydrolyzate
2007 (English)In: International Journal of Molecular Sciences, ISSN 1422-0067, E-ISSN 1422-0067, Vol. 8, no 8, p. 777-787Article in journal (Refereed)
Abstract [en]

This work deals with application of encapsulation technology to eliminate inhibition of D-limonene in fermentation of orange wastes to ethanol. Orange peel was enzymatically hydrolyzed with cellulase and pectinase. However fermentation of the released sugars in this hydrolyzate by freely suspended S. cerevisiae failed due to inhibition of limonene. On the other hand, encapsulation of S. cerevisiae in alginate membranes was a powerful tool to eliminate inhibition of limonene. The encapsulated cells were able to ferment the orange peel hydrolyzate in 7 h, and produce ethanol with yield 0.44 g/g fermentable sugars. Cultivation of the encapsulated yeast in defined medium was successful, even in the presence of 1.5% (v/v) limonene. The capsules’ membranes were selectively permeable to the sugars and the other nutrients, but not limonene. While 1% (v/v) limonene was present in the culture, its concentration inside the capsules was not more than 0.054% (v/v).

Place, publisher, year, edition, pages
Molecular Diversity Preservation International (MDPI) AG., 2007
Keywords
orange peels, encapsulated yeast, alginate membrane, ethanol, limonene, enzymatic hydrolysis, Energi och material
National Category
Industrial Biotechnology
Identifiers
urn:nbn:se:hb:diva-2295 (URN)10.3390/i8080777 (DOI)2320/2958 (Local ID)2320/2958 (Archive number)2320/2958 (OAI)
Available from: 2015-11-13 Created: 2015-11-13 Last updated: 2017-12-01
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