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The sugar beet (Beta vulgaris) plant has in recent years been added to the Biofuel Industrial Strategy (Department of Minerals and Energy, 2007) by the South African government as a crop grown for the production of bio-ethanol. Sugar beet is commonly grown in Europe for the production of sucrose and has recently been cultivated in Cradock and the surrounding areas (Engineering News, 2008). The biofuel industry usually ferments the sucrose with Saccharomyces cerevisiae to yield bio-ethanol. However, researchers are presented with a critical role to increase current yields as there are concerns over the process costs from industrial biotechnologists. The beet factories produce a pulp by-product removed of all sucrose. The hemicellulose-rich pulp can be degraded by microbial enzymes to simple sugars that can be subsequently fermented to bio-ethanol. Thus, the pulp represents a potential source for second generation biofuel. The process of utilising microbial hemicellulases requires an initial chemical pre-treatment step to delignify the sugar beet pulp (SBP). An alkaline pre-treatment with ‘slake lime’ (calcium hydroxide) was investigated using a 23 factorial design and the factors examined were: lime load; temperature and time. The analysed results showed the highest release of reducing sugars at the pre-treatment conditions of: 0.4 g lime / g SBP; 40°C and 36 hours. A partial characterisation of the Clostridium cellulovorans hemicellulases was carried out to verify the optimal activity conditions stated in literature. The highest release of reducing sugars was measured at pH 6.5 – 7.0 and at 45°C for arabinofuranosidase A (ArfA); at pH 5.5 and 40°C for mannanase A (ManA) and pH 5.0 – 6.0 and 45°C for xylanase A (XynA). Temperature studies showed that a complete loss of enzymatic activity occurred after 11 hours for ManA; and 84-96 hours for ArfA. XynA was still active after 120 hours. The optimised lime pre-treated SBP was subsequently degraded using various combinations and percentages of C. cellulovorans ArfA, ManA and XynA to determine the maximal release of reducing sugars. Synergistically, the highest synergy was observed at 75% ArfA and 25% ManA, with a specific activity of 2.9 μmol/min/g protein. However, the highest release of sugars was observed at 4.2 μmol/min/g protein at 100% ArfA. This study has initiated the research within South Africa on SBP and its degradation by C. cellulovorans. Preliminary studies show that SBP has the potential to be utilised as a second generation biofuel source.

Submitted by Caroline Falcao (caroline.rfalcao@ufpe.br) on 2017-06-08T18:51:11Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) 2012-dissertacao-RuteBarbosa.pdf.pdf: 7071839 bytes, checksum: 55f34652e0375ea49ad4d860f49fea1f (MD5) / Made available in DSpace on 2017-06-08T18:51:11Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) 2012-dissertacao-RuteBarbosa.pdf.pdf: 7071839 bytes, checksum: 55f34652e0375ea49ad4d860f49fea1f (MD5) Previous issue date: 2012-05-28 / Durante o século XIX, a crise no sistema dos engenhos banguês colocou em cheque o prestígio político e econômico dos proprietários do açúcar no norte de Alagoas. Na tentativa de melhorar esta situação, os proprietários destes empreendimentos agrícolas criaram diversas estratégias para não perder o tão almejado status de senhor de engenho. Estas estratégias são perceptíveis através da cultura material, que durante o período oitocentista atuou como demarcador de posições sociais em decorrência dos novos padrões de comportamento voltados a um modo de vida mais civilizado, cosmopolita e burguês. Neste contexto, as louças assumiram um papel importante, agindo como poderosos instrumentos de ação social, comunicando simbolicamente identidades, hierarquia e poder. Este estudo busca compreender os significados atribuídos as louças pelos produtores de açúcar no norte de Alagoas. Para isso, foram analisados fragmentos de louças oriundas de cinco engenhos e um entreposto comercial, sendo três desses engenhos banguês e dois movidos a vapor. / During the 19th century a crisis in the sugar economy, felt particularly by the mills run by animal or water power, put in check plantation owners’ economic and political prestige in the north of Alagoas State. In an attempt to ameliorate this situation, the owners created diverse strategies to secure their coveted role as plantation masters and all this signified within society at that time. Their strategies are discernible in the material culture, which, during this 19th century functioned as markers of social position in the face of new behavior patterns geared to a more civilized, cosmopolitan and bourgeois life. In this context, refined earthenwares assumed an important role, serving as powerful instruments for social action, symbolically communicating social identity, hierarchy and power. The present study seeks to understand the meaning attributed to refined eathenwares by owners and their families in northern Alagoas State. To this end, five sugar plantations and a commercial port provided the ceramic assemblage analyzed in order to detect consumption patterns in the archaeological record of these sites. Of the sugar mills compared, two were steam powered and three were run by either water or animal traction.