- Email: [email protected]
Enzymatic Activation of Softwood Dissolving Pulps
S508
Special Abstracts / Journal of Biotechnology 150S (2010) S1–S576
husk extracts, using two different systems (DPPH radical scavenging test and -carotene bleaching test), and compared with commonly used industrial antioxidants; water extractives showed an interesting antioxidant activity in emulsion. We proceeded with a mild alkaline treatment followed by an enzymatic treatment to improve lignin purity (final yield and purity of recovered lignin were 25.7% and 74.8%). Because lignin structure and functional groups can influence its industrial application, recovered lignin was submitted to a Gel Permeation Chromatography and 31 P-NMR characterization; preliminary studies (among which lignin antioxidant activity evaluation) were also performed to investigate its potential industrial application.
polymorphism analysis because of the absence of missense mutations. doi:10.1016/j.jbiotec.2010.09.799 [P-P&F.97] Enzymatic Activation of Softwood Dissolving Pulps Tarja Tamminen 1,∗ , Matti Siika-aho 1 , Tiina Liitiä 1 , Roland Adden 3 , Helena Parviainen 2 , Sirkka-Liisa Maunu 2 1
Technical Research Centre of Finland, VTT, Finland University of Helsinki, Laboratory of Polymer Chemistry, Finland 3 Dow Wolff Cellulosics GmbH, Research & Development, Germany Keywords: Dissolving pulp; Activation; Enzyme; Steam explosion 2
doi:10.1016/j.jbiotec.2010.09.798 [P-P&F.96] Different gene expression pattern of Populus alba L. genotypes under elevated UV-B radiation Kostlend Mara 1,∗ , Donatella Paffetti 1 , Ilaria Spanu 1 , Giovanni Emiliani 1 , Sabrina Raddi 1 , Cristina Vettori 2 1 Department of Agricultural and Forest Economics, Engineering, Sciences and Technologies - University of Florence, Italy 2 Institute of Plant Genetics - CNR, Research Division Florence, Italy Keywords: UV-B stress; Gene expression; Ecophysiology; Poplar
Long-term depletion of the stratospheric ozone layer contributes to an increase in terrestrial solar ultraviolet-B radiation. When exposed to elevated ultraviolet-B radiation (280-315 nm), plants display a wide variety of physiological and morphological responses. In this work, starting from previous microarray dataset used to assess transcriptome changes in Populus alba L. under UV-B radiation, we analysed the differential response of 5 poplar genotypes selected along a latitudinal and altitudinal gradient. Three years old rooted plants were acclimated in two identical phytotrons, except the presence of a UVB lamp array in just one of them. In order to simulate an environmental condition, plants were treated for 16 hours with an UVBbe (UVB biologically effective radiation) supplementary dose of 6 KJ/m2/day and allowed to recover during the night (8 hours). After plants were first adapted for 30 min in total darkness, chlorophyll fluorescence of PSII was measured. The ecophysiological data showed a decrease of the maximum efficiency of the PSII in the stressed plants, in particular for 3 clones, during the hours of the UVB treatment. We studied also, the association between polymorphism data (SNP) and expression level on genes (such as chs, comt, rbcl, and photolyase) putatively related to UV-B response. The leaf tissue of the 5 genotypes were sampled after treatment for 3, 6, 12 and 36 hours with UVB, and were analyzed using qRTPCR. Chs gene show high expression levels after 12 (3 genotypes) and 36 hours (1 genotype) of treatment, while comt gene show high levels of expression after 12 hours (4 genotypes) of treatment. Instead, photolyase gene show high levels of transcription just after 3 hours (1 genotype) of treatment and later his expression levels decreases. The qRT-PCR data show that there is not a significant difference of expression patterns for rbcL among the genotypes with a decrease that is consistent with the eco-physiological results. The results showed a different pattern of expression, with a dissimilar response among the clones analyzed towards the stress. Must still be clarified the association between the ecophysiological and expression data, with the sequences
Sulfite pulping of wood can be used to produce dissolving grade pulp for the textile industry, but it might also be applied more widely in the cellulose-based industries as raw material for carboxymethyl cellulose, methyl cellulose and corresponding products. Dissolving pulps are composed of pure cellulose with very low hemicellulose content. On the other hand, fiber strength is not an issue in this case. The chemical composition can be adjusted by proper selection of the cooking parameters and extending the cook below the optimum for paper grade pulping. This process yields pulps that are applicable as dissolving pulps, but their solubility is not adequate for the manufacturing of cellulose derivatives. However, it could potentially be improved by activating treatments. Steam explosion has been studied as an activating treatment for dissolving pulps. Its effect is probably based on partial degradation of the fiber structure, thus enhancing the penetration of chemicals. Another approach has been to apply endoglucanase type enzymes for the same purpose. Both methods have been shown to be potentially interesting. However, there are drawbacks as well related to them, such as yield loss, which needs to be minimised. In this study, dissolving grade pulps from Domsjö were activated by steam explosion or endoglucanases alone or in combination. Both commercial and experimental enzymes were studied. The effects of the treatments were followed by intrinsic viscosity and molar mass measurements. Steam explosion reduced pulp viscosity dramatically, but the following enzyme treatment did not affect it much further. Without preceding steam explosion, the enzymes alone reduced viscosity, but to a lesser extent than steam explosion. Size exclusion chromatography showed that the degradation by the enzymes was heterogeneous, leaving behind both intact high molecular cellulose and degraded material, whereas steam explosion led to less broad molar mass distributions at the low molecular region. The yield loss during the enzyme treatments was evaluated based on dissolved sugars. As expected, it was found to be lowest with the pure experimental enzymes. The effects of the treatments on solubility were evaluated by dissolution in alkaline urea. All activated pulps were more readily soluble than the starting pulps, suggesting that their performance might be improved even in respect to practical applications. Financial support from Tekes (WoodWisdom Research Programme, project ReCell) is gratefully acknowledged. doi:10.1016/j.jbiotec.2010.09.800
Special Abstracts / Journal of Biotechnology 150S (2010) S1–S576
husk extracts, using two different systems (DPPH radical scavenging test and -carotene bleaching test), and compared with commonly used industrial antioxidants; water extractives showed an interesting antioxidant activity in emulsion. We proceeded with a mild alkaline treatment followed by an enzymatic treatment to improve lignin purity (final yield and purity of recovered lignin were 25.7% and 74.8%). Because lignin structure and functional groups can influence its industrial application, recovered lignin was submitted to a Gel Permeation Chromatography and 31 P-NMR characterization; preliminary studies (among which lignin antioxidant activity evaluation) were also performed to investigate its potential industrial application.
polymorphism analysis because of the absence of missense mutations. doi:10.1016/j.jbiotec.2010.09.799 [P-P&F.97] Enzymatic Activation of Softwood Dissolving Pulps Tarja Tamminen 1,∗ , Matti Siika-aho 1 , Tiina Liitiä 1 , Roland Adden 3 , Helena Parviainen 2 , Sirkka-Liisa Maunu 2 1
Technical Research Centre of Finland, VTT, Finland University of Helsinki, Laboratory of Polymer Chemistry, Finland 3 Dow Wolff Cellulosics GmbH, Research & Development, Germany Keywords: Dissolving pulp; Activation; Enzyme; Steam explosion 2
doi:10.1016/j.jbiotec.2010.09.798 [P-P&F.96] Different gene expression pattern of Populus alba L. genotypes under elevated UV-B radiation Kostlend Mara 1,∗ , Donatella Paffetti 1 , Ilaria Spanu 1 , Giovanni Emiliani 1 , Sabrina Raddi 1 , Cristina Vettori 2 1 Department of Agricultural and Forest Economics, Engineering, Sciences and Technologies - University of Florence, Italy 2 Institute of Plant Genetics - CNR, Research Division Florence, Italy Keywords: UV-B stress; Gene expression; Ecophysiology; Poplar
Long-term depletion of the stratospheric ozone layer contributes to an increase in terrestrial solar ultraviolet-B radiation. When exposed to elevated ultraviolet-B radiation (280-315 nm), plants display a wide variety of physiological and morphological responses. In this work, starting from previous microarray dataset used to assess transcriptome changes in Populus alba L. under UV-B radiation, we analysed the differential response of 5 poplar genotypes selected along a latitudinal and altitudinal gradient. Three years old rooted plants were acclimated in two identical phytotrons, except the presence of a UVB lamp array in just one of them. In order to simulate an environmental condition, plants were treated for 16 hours with an UVBbe (UVB biologically effective radiation) supplementary dose of 6 KJ/m2/day and allowed to recover during the night (8 hours). After plants were first adapted for 30 min in total darkness, chlorophyll fluorescence of PSII was measured. The ecophysiological data showed a decrease of the maximum efficiency of the PSII in the stressed plants, in particular for 3 clones, during the hours of the UVB treatment. We studied also, the association between polymorphism data (SNP) and expression level on genes (such as chs, comt, rbcl, and photolyase) putatively related to UV-B response. The leaf tissue of the 5 genotypes were sampled after treatment for 3, 6, 12 and 36 hours with UVB, and were analyzed using qRTPCR. Chs gene show high expression levels after 12 (3 genotypes) and 36 hours (1 genotype) of treatment, while comt gene show high levels of expression after 12 hours (4 genotypes) of treatment. Instead, photolyase gene show high levels of transcription just after 3 hours (1 genotype) of treatment and later his expression levels decreases. The qRT-PCR data show that there is not a significant difference of expression patterns for rbcL among the genotypes with a decrease that is consistent with the eco-physiological results. The results showed a different pattern of expression, with a dissimilar response among the clones analyzed towards the stress. Must still be clarified the association between the ecophysiological and expression data, with the sequences
Sulfite pulping of wood can be used to produce dissolving grade pulp for the textile industry, but it might also be applied more widely in the cellulose-based industries as raw material for carboxymethyl cellulose, methyl cellulose and corresponding products. Dissolving pulps are composed of pure cellulose with very low hemicellulose content. On the other hand, fiber strength is not an issue in this case. The chemical composition can be adjusted by proper selection of the cooking parameters and extending the cook below the optimum for paper grade pulping. This process yields pulps that are applicable as dissolving pulps, but their solubility is not adequate for the manufacturing of cellulose derivatives. However, it could potentially be improved by activating treatments. Steam explosion has been studied as an activating treatment for dissolving pulps. Its effect is probably based on partial degradation of the fiber structure, thus enhancing the penetration of chemicals. Another approach has been to apply endoglucanase type enzymes for the same purpose. Both methods have been shown to be potentially interesting. However, there are drawbacks as well related to them, such as yield loss, which needs to be minimised. In this study, dissolving grade pulps from Domsjö were activated by steam explosion or endoglucanases alone or in combination. Both commercial and experimental enzymes were studied. The effects of the treatments were followed by intrinsic viscosity and molar mass measurements. Steam explosion reduced pulp viscosity dramatically, but the following enzyme treatment did not affect it much further. Without preceding steam explosion, the enzymes alone reduced viscosity, but to a lesser extent than steam explosion. Size exclusion chromatography showed that the degradation by the enzymes was heterogeneous, leaving behind both intact high molecular cellulose and degraded material, whereas steam explosion led to less broad molar mass distributions at the low molecular region. The yield loss during the enzyme treatments was evaluated based on dissolved sugars. As expected, it was found to be lowest with the pure experimental enzymes. The effects of the treatments on solubility were evaluated by dissolution in alkaline urea. All activated pulps were more readily soluble than the starting pulps, suggesting that their performance might be improved even in respect to practical applications. Financial support from Tekes (WoodWisdom Research Programme, project ReCell) is gratefully acknowledged. doi:10.1016/j.jbiotec.2010.09.800