Integrated bioconversion of pulp and paper primary sludge to second generation bioethanol using Saccharomyces cerevisiae ATCC 26602

Investigation on utilization of sludge waste from Wastewater Treatment Plant (WWTP) of pulp and paper mill for bioethanol feedstock in a batch system at laboratory scale has been carried out. Experiments were conducted in three phases, namely the hydrolysis process; the fermentation process by Saccharomyces cerevisiae and the simultaneous saccharification-fermentation experiments. Ethanol concentration produced was tested by the HPLC method. Results show that t primary sludge from paper mills made from virgin pulp (sludge A) and primary sludge from pulp and paper made from raw wood (sludge B) at a 2% total solids having potential as raw material for bioethanol. The optimum conditions of the hydrolysis process of sludge A and sludge B is obtained from the sludge solids content of 6%, with the addition of cellulase of 9 FPU/g cellulose and beta-glucosidase of 6.7 IU/FPU for the incubation time of 48 hours producing the reducing sugar content of 31.3% and 36.2% with the hydrolysis efficiency of 64% and 71% respectively. On the SSF process conditions at pH of 4.5, temperature of 28oC for 96 hours, the sludge substrate A can produce ethanol with the concentration of 3.45% and the process efficiency of 72.5% and the sludge substrate B can produce ethanol with the concentration of 2.89% and the process efficiency of 60.8%.Keywords: bioethanol, cellulase, hydrolysis, fermentation, Saccharomyces cerevisiae, sludge ABSTRAK Penelitian pemanfaatan sludge Instalasi Pengolahan Air Limbah (IPAL) industri pulp dan kertas untuk bahan baku bioetanol dengan sistem batch pada skala laboratorium telah dilakukan. Percobaan dilakukan dalam tiga tahapan yaitu proses hidrolisis dengan enzim; proses fermentasi dengan Saccharomyces cerevisiae dan proses sakarifikasi-fermentasi serentak (SFS) pada satu reaktor. Kadar etanol yang dihasilkan diuji dengan metode HPLC. Hasil percobaan menunjukkan bahwa dari 4 jenis sludge yang diteliti, sludge primer dari pabrik kertas berbahan baku virgin pulp (sludge A) dan dari pabrik pulp dan kertas berbahan baku kayu (sludge B) berpotensi sebagai bahan baku bioetanol. Kondisi optimum percobaan proses hidrolisis sludge A dan sludge B diperoleh dari perlakuan dengan kadar padatan 6%, dosis selulase 9 FPU/g selulosa; dosis beta glukosidase 6,7 IU/FPU dengan lama inkubasi 48 jam, masing-masing menghasilkan kadar gula pereduksi sebesar 31,3% dan 36,2% dengan efisiensi hidrolisis 64% dan 71%. Pada percobaan SFS dengan kondisi proses pH 4,5 pada suhu 28oC selama 96 jam, substrat sludge A dapat menghasilkan etanol sebesar 3,45% dengan efisiensi proses 72,5% dan substrat sludge B dapat menghasilkan etanol sebesar 2,89% dengan efisiensi proses 60,8%.Kata kunci: bioetanol, selulase, hidrolisis, fermentasi, Saccharomyces cerevisiae, sludge

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Evaluation of The Production of Second Generation Ethanol by Co-Culture of Saccharomyces Cerevisiae and Pachysolen Tannophilus Immobilized in Sodium Alginate.

10.21203/rs.3.rs-525446/v1 ◽

2021 ◽

Author(s):

Marcello Lima Bertuci ◽

Mariane Daniella da Silva ◽

João Pedro Cano ◽

Crispin Humberto Garcia Cruz

Keyword(s):

Saccharomyces Cerevisiae ◽

Ethanol Production ◽

Environmental Impacts ◽

Fossil Fuels ◽

Second Generation ◽

Synthetic Medium ◽

Alternative Form ◽

Pachysolen Tannophilus ◽

Second Generation Bioethanol ◽

Agroindustrial Waste

Abstract The production of an alternative form of fuel that replaces fossil fuels has been increasingly studied due to the environmental impacts generated by its excessive use, as well as the depletion of these fossil energy sources. Ethanol obtained from the crushing of sugar cane has been used as a substitute for these fuels, mainly in the automotive area. However, alternative sources are being studied to produce the so called second generation bioethanol. This would avoid competition for food producing agricultural areas and agroindustrial waste is a great source for obtaining it. In general, these residues are not always completely reused and are disposed of inappropriately in the environment, becoming contaminants. Therefore, the use of agroindustrial waste can become a renewable source of energy, in addition to reducing environmental impacts. The objective of this work is to produce second generation bioethanol as an alternative to the one currently used, using the rice husk hydrolyzate by the consortium formed by Saccharomyces cerevisiae and Pachysolen tannophilus . For this, an acid hydrolysis was performed with 2% sulfuric acid during 10 minutes of heating in an autoclave, after which the hydrolyzate was detoxified with the use of activated carbon. The crude and detoxified hydrolysates were used as a substrate for the fermentation medium with an initial concentration of 50 mg/mL of reducing sugars. The fermentation process with the use of both yeasts in the crude hydrolyzate medium, in the detoxified medium and in a synthetic medium composed of glucose, was carried out for 24 h, 30º C, 0 rpm and pH 6.5.The best results for the ethanol production of Saccharomyces cerevisiae was the synthetic medium with 20.6 mg/mL. For the yeast Pachysolen tannophilus , its highest production was in a synthetic medium with 11.67 mg/mL. The intercropping of the two yeasts proved to be efficient with a greater ethanol production reaching 21.5 mg/mL, the hydrolyzed and detoxified media showed great potential for ethanol production both in intercropping and in monoculture

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Engineering a wild-type diploid Saccharomyces cerevisiae strain for second-generation bioethanol production

Bioresources and Bioprocessing ◽

10.1186/s40643-016-0126-4 ◽

2016 ◽

Vol 3 (1) ◽

Cited By ~ 33

Author(s):

Hongxing Li ◽

Yu Shen ◽

Meiling Wu ◽

Jin Hou ◽

Chunlei Jiao ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Second Generation ◽

Bioethanol Production ◽

Wild Type ◽

Second Generation Bioethanol

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Screening and Mutation of Saccharomyces cerevisiae UV-20 with a High Yield of Second Generation Bioethanol and High Tolerance of Temperature, Glucose and Ethanol

Indian Journal of Microbiology ◽

10.1007/s12088-018-0741-1 ◽

2018 ◽

Vol 58 (4) ◽

pp. 440-447 ◽

Cited By ~ 2

Author(s):

Shi Yi ◽

Xiao Zhang ◽

Han-xin Li ◽

Xiao-xia Du ◽

Shao-wei Liang ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Second Generation ◽

High Yield ◽

High Tolerance ◽

Second Generation Bioethanol

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Second Generation Bioethanol Production: On the Use of Pulp and Paper Industry Wastes as Feedstock

Fermentation ◽

10.3390/fermentation5010004 ◽

2018 ◽

Vol 5 (1) ◽

pp. 4 ◽

Cited By ~ 31

Author(s):

Rita Branco ◽

Luísa Serafim ◽

Ana Xavier

Keyword(s):

Fossil Fuels ◽

Second Generation ◽

Paper Industry ◽

Pulp And Paper Industry ◽

Pulp And Paper ◽

Environmental Benefits ◽

Bioethanol Production ◽

Paper Mills ◽

Second Generation Bioethanol ◽

High Level

Due to the health and environment impacts of fossil fuels utilization, biofuels have been investigated as a potential alternative renewable source of energy. Bioethanol is currently the most produced biofuel, mainly of first generation, resulting in food-fuel competition. Second generation bioethanol is produced from lignocellulosic biomass, but a costly and difficult pretreatment is required. The pulp and paper industry has the biggest income of biomass for non-food-chain production, and, simultaneously generates a high amount of residues. According to the circular economy model, these residues, rich in monosaccharides, or even in polysaccharides besides lignin, can be utilized as a proper feedstock for second generation bioethanol production. Biorefineries can be integrated in the existing pulp and paper industrial plants by exploiting the high level of technology and also the infrastructures and logistics that are required to fractionate and handle woody biomass. This would contribute to the diversification of products and the increase of profitability of pulp and paper industry with additional environmental benefits. This work reviews the literature supporting the feasibility of producing ethanol from Kraft pulp, spent sulfite liquor, and pulp and paper sludge, presenting and discussing the practical attempt of biorefineries implementation in pulp and paper mills for bioethanol production.

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Novel Propagation Strategy of Saccharomyces cerevisiae for Enhanced Xylose Metabolism during Fermentation on Softwood Hydrolysate

Fermentation ◽

10.3390/fermentation7040288 ◽

2021 ◽

Vol 7 (4) ◽

pp. 288

Author(s):

Andreea Cristina Dobrescu ◽

Henrique César Teixeira Veras ◽

Cristiano Varrone ◽

Jan Dines Knudsen

Keyword(s):

Saccharomyces Cerevisiae ◽

Second Generation ◽

Xylose Fermentation ◽

Carbon Sources ◽

Fed Batch ◽

Xylose Metabolism ◽

Second Generation Bioethanol ◽

Utilisation Rate ◽

Shake Flasks ◽

Production Strategy

An economically viable production of second-generation bioethanol by recombinant xylose-fermenting Saccharomyces cerevisiae requires higher xylose fermentation rates and improved glucose–xylose co-consumption. Moreover, xylose-fermenting S. cerevisiae recognises xylose as a non-fermentable rather than a fermentable carbon source, which might partly explain why xylose is not fermented into ethanol as efficiently as glucose. This study proposes propagating S. cerevisiae on non-fermentable carbon sources to enhance xylose metabolism during fermentation. When compared to yeast grown on sucrose, cells propagated on a mix of ethanol and glycerol in shake flasks showed up to 50% higher xylose utilisation rate (in a defined xylose medium) and a double maximum fermentation rate, together with an improved C5/C6 co-consumption (on an industrial softwood hydrolysate). Based on these results, an automated propagation protocol was developed, using a fed-batch approach and the respiratory quotient to guide the ethanol and glycerol-containing feed. This successfully produced 71.29 ± 0.91 g/L yeast with an average productivity of 1.03 ± 0.05 g/L/h. These empirical findings provide the basis for the design of a simple, yet effective yeast production strategy to be used in the second-generation bioethanol industry for increased fermentation efficiency.

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