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Bioconversion of paper sludge to biofuel by simultaneous saccharification and fermentation using a cellulase of paper sludge origin and thermotolerant Saccharomyces cerevisiae TJ14
Joni Prasetyo, Kazuya Naruse, Tatsuya Kato, Chuenchit Boonchird, Satoshi Harashima, Enoch Y Park
Biotechnology for Biofuels , 2011, DOI: 10.1186/1754-6834-4-35
Abstract: When 50 g PS organic material (PSOM)/l was used in SSF, the ethanol yield based on PSOM was 23% (g ethanol/g PSOM) and was two times higher than that obtained by a separate hydrolysis and fermentation process. Cellulase activity throughout SSF remained at around 60% of the initial activity. When 50 to 150 g PSOM/l was used in SSF, the ethanol yield was 21% to 23% (g ethanol/g PSOM) at the 500 ml Erlenmeyer flask scale. Ethanol production and theoretical ethanol yield based on initial hexose was 40 g/l and 66.3% (g ethanol/g hexose) at 80 h, respectively, when 161 g/l of PSOM, 15 filter paper units (FPU)/g PSOM, and 20% inoculum were used for SSF, which was confirmed in the 2 l scale experiment. This indicates that PS is a good raw material for bioethanol production.Ethanol concentration increased with increasing PSOM concentration. The ethanol yield was stable at PSOM concentrations of up to 150 g/l, but decreased at concentrations higher than 150 g/l because of mass transfer limitations. Based on a 2 l scale experiment, when 1,000 kg PS was used, 3,182 kFPU cellulase was produced from 134.7 kg PS. Produced cellulase was used for SSF with 865.3 kg PS and ethanol production was estimated to be 51.1 kg. Increasing the yeast inoculum or cellulase concentration did not significantly improve the ethanol yield or concentration.Recently, much research has been conducted on reducing the input energy and cost of ethanol production. Around 5 million tons of paper sludge (PS) is discharged annually by the paper manufacturing industry in Japan. Disposing of PS in landfill or by incineration creates environmental problems, and legislative trends in many countries are restricting the amount and types of materials that are permitted to be disposed of by landfill [1]. The production of bioethanol from PS can reduce dependence on fossil fuels while simultaneously solving the environmental problems associated with PS disposal. The use of bioethanol produced from PS offers an alternat
Factors of Effecting Hydrogen Production from Anaerobic Fermentation of Excess Sewage Sludge
污泥厌氧发酵产氢的影响因素

CAI Mu-lin,LIU Jun-xin,
蔡木林
,刘俊新

环境科学 , 2005,
Abstract: Large amounts of sewage sludge is produced from the treatment of wastewater by biological processes, which is usually treated by anaerobic digestion to produce methane gas. Acetogenesis and hydrogen are an intermediate phase during the anaerobic digestion. Batch tests of fermentative hydrogen production under different initial pH (3.0 - 12.5) were compared using the raw sludge and alkaline pretreated sludge. The influences of the characteristics and concentration of sludge were also examined thereafter. Results show that the optimal initial pH for biohydrogen production from sewage sludge was around 11.0. Under this optimal condition, the biohydrogen yield of raw sludge was 8.1 mL/g, and it would reach to 16.9 mL/g when the sludge was pretreated by alkali. Furthermore, there is no methane generation during the biohydrogen fermentation of the alkaline pretreatment sludge in 4 days and the hydrogen consumption is also slowed down. In addition, a low VSS/SS rate will reduce the hydrogen yield, while the concentrations of sludge have no obvious compact on it.
Fermentative Production of L-Lysine: Bacterial Fermentation-I  [PDF]
Abdul Haleem Shah,Abdul Hameed,Gul Majid Khan
Journal of Medical Sciences , 2002,
Abstract: Lysine is an essential, economically important amino acid used as food and feed supplement. It has also some pharmaceutical applications in the formulation of diets with balanced amino acid composition and in amino acid infusions. Chemical, enzymatic and fermentation processes have been used to synthesize lysine. This review outlines the efforts of various researchers, which provide useful information regarding the fermentative production of lysine by bacteria. It also discusses different methods, including the development of new auxotrophic mutants and optimization of culture conditions used in order to improve the total yield and quality of lysine.
Obtaining lactic acid by descontinuous fermentation using different fermentative media  [cached]
Roselene Ferreira Oliveira,Heron Oliveira dos Santos Lima,Mirela Vanin dos Santos Lima
Revista Brasileira de Pesquisa em Alimentos , 2011,
Abstract: Lactic acid has multiple uses in several industries such as food, cereal derivates, beverage, cosmetic, chemical and pharmaceutical. Due to its wide applicability the process to obtain lactic acid is one of the most studied processes. The aim of this study was to produce lactic acid using fermentation of cassava meal (residue from cleaning the flour mill) and cassava starch (amilacious fractions of tuberous root raw materials) previously hydrolyzed and supplemented. The fermentation of both cassava meal and cassava starch was carried out using a solution at 18% (m/v), previously hydrolyzed with thermostable alpha amylase (Termamyl 120L) and amyloglucosidase (AMG 300L); supplemented with yeast extract and peptone. The microorganism, Lactobacillus casei, was inoculated under the following process conditions: pH 6.4; at 37°C and agitation at 100 rpm for 96 hours. The process was periodically surveyed in order to analyze the concentration of lactic acid; concentration of reducing sugars; pH; biomass and cellular feasibility. The analysis of the results permits to conclude that both cassava meal and cassava starch are promising raw materials for obtaining lactic acid by fermentative media.
The influence of the different initial probiotic bacteria concentration on sweet whey fermentation  [cached]
Bojan Matijevi?,Katarina Lisak,Rajka Bo?ani?,Ljubica Tratnik
Mljekarstvo , 2008,
Abstract: Whey is nutritiously very high-quality secondary product from cheese making which is not used enough in human diet. When the fermentation is performed with probiotic bacteria it additionally increases its nutritional and health values. This research examines the influence of different amount of inoculum addition (2.5, 5 and 7.5 %) of monoculture Lactobacillus acidophilus La-5 or Bifidobacterium animalis subsp. lactis BB-12, on the course of fermentation of reconstitued sweet whey at 37 °C. During fermentation and 28 days of cool storage fermented whey pH value, titratable acidity and the viable cells count was monitored. Fermentation with 7.5 % inoculum of monoculture Lactobacillus acidophilus La-5 lasted the shortest (about 13.3 hours), while the fermentation with 2.5 % inoculum lasted the longest (about 15.5 hours). The viable cells count of Lactobacillus acidophilus La-5 cells in all whey samples has increased during fermentation for about 1.3 log CFU/mL and at the end of fermentation was about 8.5 log CFU/mL. Whey fermentation with 7.5 % added inoculum of monoculture Bifidobacterium animalis subsp. lactis BB-12 showed no difference in duration time in comparison to whey fermentation with 2.5 % inoculum addition. The viable cells count of Bifidobacterium animalis subsp. lactis BB-12 has increased during fermentation for about 0.9 log CFU/mL and at the end of fermentation was about 8.7 log CFU/mL. The amount of inoculum had no influence on survival of probiotic bacteria in fermented whey regardless of monoculture used.
Influence of temperature and sugar addition on soymilk fermentation by probiotic bacteria  [cached]
Rajka Bo?ani?,Silvija Brleti?,Sandy Lovkovi?
Mljekarstvo , 2008,
Abstract: Fermented soymilk beverages were produced by fermentation withmonocultures of probiotic bacteria: Bifidobacterium lactis Bb12, Lactobacillus acidophilus La5 and Lactobacillus casei Lc01 (Chr. Hansen’s, Denmark), at two different temperatures (37 °C and 43 °C), with and without 5 % sugar addition (sucrose for Bb12 and La5, and glucose for Lc01). pHvalues and numbers of viable cells were measured throughout the fermentation. For all tested probiotic bacteria temperature 37 °C was more appropriated than 43 °C. The fermentation process in the case of all three monocultures were shortened by an addition of sugars and viable counts at the end of the fermentation were increased. The influence of sugar on acid production and viable cells count was greatest in soymilk fermented with monoculture L. casei Lc-01. The choice of monoculture did not have a significant influence on the appearance and consistency of the fermented soymilk, apart when the achieved acidity was not enough and soymilk did not coagulate, like in the case of fermentation with strain Lc-01 without glucose addition.
Screening and Fermentation Characteristics of PHA Bacteria in Activated Sludge  [PDF]
Fang Yang, Rui Zhu
Engineering (ENG) , 2013, DOI: 10.4236/eng.2013.510B096
Abstract:

Using sludge at the bottom of Hengshui Lake as samples, and screened out the SJ-9 strain with PHA synthesis capability by enrichment, purification, Nile blue staining, far-infrared spectroscopy and gas qualitative and quantitative analysis. The infrared scanning of SJ-9 bacteria product showed that this product was middle chain PHA. Optimization of SJ-9 fermentation conditions obtained the optimal conditions with optimal carbon source of sodium butyrate, optimal C/N of 35, optimal fermentation time of 120 h, and optimal initial pH for culture substrate of 7.0. 10 L fermenter amplification culture under these conditions showed consistent results with flask culture, and the bacteria and PHA had the highest yields at 120 h, with the maximal yields of 6.81 and 2.36 g/L, respectively.

PURPOSE OF TREATMENTS FOR THE SLUDGE PAPER RECYCLING
Ivie Emi Sakuma Kawatoko,Maria Cristina Rizk
Engenharia Ambiental : Pesquisa e Tecnologia , 2011,
Abstract: The sludge generated in the paper recycling industries presents characteristics of a fibrous mass of brown color, being classified as residue II A – no inert. Nowadays, the companies are looking for alternatives for reuse the sludge as inputs in other processes, with the intention to avoid or to reduce environmental liabilities.Thus, this work was the studies of the construction, operation and monitoring of a windrow composting, as well as the sizing of bed dryers, filter press and centrifuges for the sludge’s treatment and its disposal in landfill. Finally, it was concluded that composting was presented as a good alternative for reuse of this material when applied in consortium with pruning and weeding wastes. Physical treatments that require less land available, such as filter presses and centrifuges, which speed up the drainage, resulting in compact and sophisticated units from the point of view of operation and maintenance, they can also be employed.
pH dependency of hydrogen fermentation from alkali-pretreated sludge
Benyi Xiao,Junxin Liu
Chinese Science Bulletin , 2006, DOI: 10.1007/s11434-006-0399-7
Abstract: Batch tests were carried out to study the possibility of hydrogen production from alkali-pretreated sludge without seed and the pH dependency of hydrogen fermentation from alkali-pretreated sludge. Experimental results showed that the sewage sludge with alkali-pretreatment could be successfully applied to biologically producing hydrogen without seed and extra-feed. The results also showed that the initial pH value of sewage sludge was an important factor throughout the hydrogen fermentation of alkali-pretreated sludge. The maximum hydrogen yield was obtained at initial pH value of 11.0 (14.4 mL·g VS 1). The hydrogen yield of alkali-pretreated sludge at alkaline initial pH value was much higher than that of acidic or neutral initial pH value. The optimal pH value of hydrogen production from alkali-pretreated sludge was approximately 9.5. The consumption of hydrogen could be inhibited when the pH value of sludge was above 8.5. The change of hydrogen yield at various initial pH values was similar to that of sludge SCOD. The change of sludge pH value was slow and acetate was the major component of volatile fatty acids produced in the process of hydrogen production. The yield and the constitution of volatile fatty acids were sensitive to the initial pH value.
pH dependency of hydrogen fermentation from alkali-pretreated sludge
Benyi Xiao,Junxin Liu,
XIAO
,Benyi,LIU,Junxin

科学通报(英文版) , 2006,
Abstract: Batch tests were carried out to study the possibility of hydrogen production from alkali-pretreated sludge without seed and the pH dependency of hydrogen fermentation from alkali-pretreated sludge. Experimental results showed that the sewage sludge with alkali-pretreatment could be successfully applied to biologically producing hydrogen without seed and extra-feed. The results also showed that the initial pH value of sewage sludge was an important factor throughout the hydrogen fermentation of alkali-pretreated sludge. The maximum hydrogen yield was obtained at initial pH value of 11.0 (14.4 mL·g VS 1). The hydrogen yield of alkali-pretreated sludge at alkaline initial pH value was much higher than that of acidic or neutral initial pH value. The optimal pH value of hydrogen production from alkali-pretreated sludge was approximately 9.5. The consumption of hydrogen could be inhibited when the pH value of sludge was above 8.5. The change of hydrogen yield at various initial pH values was similar to that of sludge SCOD. The change of sludge pH value was slow and acetate was the major component of volatile fatty acids produced in the process of hydrogen production. The yield and the constitution of volatile fatty acids were sensitive to the initial pH value.
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