Ozone treatment of spent medium from Auricularia polytricha cultivation for enzymatic saccharification and subsequent ethanol production

Algae are referred to as a third-generation biomass for ethanol production. However, salinity treatment is a problem that needs to be solved, because algal hydrolysates often contain high salt. Here, we isolated the salt-tolerant ethanol-producing yeast Citeromyces matritensis M37 from the east coast of Miura Peninsula in Japan. This yeast grew under osmotic stress conditions (20% NaCl or 60% glucose). It produced 6.55 g/L ethanol from YPD medium containing 15% NaCl after 48 h, and the ethanol accumulation was observed even at 20% NaCl. Using salted Undaria pinnatifida (wakame), we obtained 6.33 g/L glucose from approx. 150 g/L of the salted wakame powder with acidic and heat pretreatment followed by enzymatic saccharification, and the ethanol production reached 2.58 g/L for C. matritensis M37. The ethanol concentration was 1.4 times higher compared with that using the salt-tolerant ethanol-producing yeast Zygosaccharomyces rouxii S11.

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Ethanol production by Escherichia coli from detoxified lignocellulosic teak wood hydrolysates with high concentration of phenolic compounds

Journal of Industrial Microbiology & Biotechnology ◽

10.1093/jimb/kuab077 ◽

2021 ◽

Author(s):

Estefanía Sierra-Ibarra ◽

Jorge Alcaraz-Cienfuegos ◽

Alejandra Vargas-Tah ◽

Alberto Rosas-Aburto ◽

Ángeles Valdivia-López ◽

...

Keyword(s):

Escherichia Coli ◽

Phenolic Compounds ◽

Ethanol Production ◽

Enzymatic Saccharification ◽

Coli Strain ◽

High Concentration ◽

E Coli ◽

Thermochemical Pretreatment ◽

Teak Wood ◽

Ethanologenic Escherichia Coli

Abstract Teak wood residues were subjected to thermochemical pretreatment, enzymatic saccharification, and detoxification to obtain syrups with a high concentration of fermentable sugars for ethanol production with the ethanologenic Escherichia coli strain MS04. Teak is a hardwood, and thus a robust deconstructive pretreatment was applied followed by enzymatic saccharification. The resulting syrup contained 60 g L−1 glucose, 18 g L−1 xylose, 6 g L−1 acetate, less than 0.1 g L−1 of total furans, and 12 g L−1 of soluble phenolic compounds (SPC). This concentration of SPC is toxic to E. coli, and thus two detoxification strategies were assayed: 1) treatment with Coriolopsis gallica laccase followed by addition of activated carbon and 2) overliming with Ca(OH)2. These reduced the phenolic compounds by 40 and 76%, respectively. The detoxified syrups were centrifuged and fermented with E. coli MS04. Cultivation with the over-limed hydrolysate showed a 60% higher volumetric productivity (0.45 gETOH L−1 h−1). The bioethanol/sugars yield was over 90% in both strategies.

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Enzymatic Saccharification and Ethanol Production of Xylem from Purwodadi Botanical Garden Trees

Wood Research Journal ◽

10.51850/wrj.2012.3.2.117-120 ◽

2017 ◽

Vol 4 (1) ◽

pp. 117-120

Author(s):

Mariko Sakata ◽

Mito Tokue ◽

Rumi Kaida ◽

Teruaki Taji ◽

Yoichi Sakata ◽

...

Keyword(s):

Ethanol Production ◽

Ball Mill ◽

Trichoderma Viride ◽

Enzymatic Saccharification ◽

Botanical Garden ◽

Palo Alto ◽

Paraserianthes Falcataria ◽

Enzymatic Hydrolysis Of Cellulose ◽

Hydrolysis Of Cellulose ◽

Hydrolysis Of

Recent studies have revealed that sengon (Paraserianthes falcataria) xylem consists of soft walls which are easily hydrolysable with a commercial cellulase preparation. We felt it important to determine the saccharification levels for fast-growing tropical trees, of which sengon, one of the fastest growing tree species in Indonesia, was used as the control wood species. The aim of this study was to screen and evaluate the xylem of Purwodadi Botanical Garden trees for saccharification in order to assess their potential usefulness in bioethanol production. Saccharification and fermentation were first examined in the xylem derived from the branches of 32 trees. The xylem was then milled into powder using a ball mill, and the powdered xylem was digested with a commercial cellulase preparation (Accelerase, Palo Alto, USA) derived from Trichoderma viride. The levels of enzymatic hydrolysis of cellulose and ethanol production were higher for Firmiana malayana and Pterocarpus indicus than for sengon.

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