Impact of phenolic compounds on hydrothermal oxidation of cellulose

Jin, Fangming; Cao, Jianxun; Kishida, Hisanori; Moriya, Tsuyoshi; Enomoto, Heiji

doi:10.1016/j.carres.2007.02.013

Cited by 25 publications

(17 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The phenolic compounds have the ability to induce laccase that in turn stimulates the cellobiose-quinone-oxidoreductae enzyme; this enzyme possibly is involved in cellobiose (CMCase and FPase inhibitor) oxidation to cellobionic acid and thus eVecting the cellulase synthesis indirectly [4,43]. Among various phenolics, e.g.…”

Section: Phenolic Compoundsmentioning

confidence: 99%

Bioconversion of lignocellulosic biomass: biochemical and molecular perspectives

Kumar

Singh

2008

J Ind Microbiol Biotechnol

1,052

530

View full text Add to dashboard Cite

In view of rising prices of crude oil due to increasing fuel demands, the need for alternative sources of bioenergy is expected to increase sharply in the coming years. Among potential alternative bioenergy resources, lignocellulosics have been identified as the prime source of biofuels and other value-added products. Lignocelluloses as agricultural, industrial and forest residuals account for the majority of the total biomass present in the world. To initiate the production of industrially important products from cellulosic biomass, bioconversion of the cellulosic components into fermentable sugars is necessary. A variety of microorganisms including bacteria and fungi may have the ability to degrade the cellulosic biomass to glucose monomers. Bacterial cellulases exist as discrete multi-enzyme complexes, called cellulosomes that consist of multiple subunits. Cellulolytic enzyme systems from the filamentous fungi, especially Trichoderma reesei, contain two exoglucanases or cellobiohydrolases (CBH1 and CBH2), at least four endoglucanases (EG1, EG2, EG3, EG5), and one beta-glucosidase. These enzymes act synergistically to catalyse the hydrolysis of cellulose. Different physical parameters such as pH, temperature, adsorption, chemical factors like nitrogen, phosphorus, presence of phenolic compounds and other inhibitors can critically influence the bioconversion of lignocellulose. The production of cellulases by microbial cells is governed by genetic and biochemical controls including induction, catabolite repression, or end product inhibition. Several efforts have been made to increase the production of cellulases through strain improvement by mutagenesis. Various physical and chemical methods have been used to develop bacterial and fungal strains producing higher amounts of cellulase, all with limited success. Cellulosic bioconversion is a complex process and requires the synergistic action of the three enzymatic components consisting of endoglucanases, exoglucanases and beta-glucosidases. The co-cultivation of microbes in fermentation can increase the quantity of the desirable components of the cellulase complex. An understanding of the molecular mechanism leading to biodegradation of lignocelluloses and the development of the bioprocessing potential of cellulolytic microorganisms might effectively be accomplished with recombinant DNA technology. For instance, cloning and sequencing of the various cellulolytic genes could economize the cellulase production process. Apart from that, metabolic engineering and genomics approaches have great potential for enhancing our understanding of the molecular mechanism of bioconversion of lignocelluloses to value added economically significant products in the future.

show abstract

Section: Phenolic Compoundsmentioning

confidence: 99%

Bioconversion of lignocellulosic biomass: biochemical and molecular perspectives

Kumar

Singh

2008

J Ind Microbiol Biotechnol

1,052

530

View full text Add to dashboard Cite

show abstract

“…In contrast, water is a convenient solvent for biomass deconstruction because the properties of water, such as dielectric constant, density, and ionic product, can be adjusted with the temperature and pressure. There are numerous studies [11,151,25,51,60,64,68,70,71,97,98,104,124,149,152,151] on the biomass conversion in hot temperature water (HTW) and supercritical water (SCW). HTW is broadly defined to be subcritical liquid water (150°C \ T \ 374°C), and SCW is water at temperatures and pressures above the critical point (T [ 374°C and P [ 221 bar) [3,120].…”

Section: Introductionmentioning

confidence: 99%

Catalytic Conversion of Lignocellulosic Biomass to Value-Added Organic Acids in Aqueous Media

Lin

Liu

et al. 2014

Green Chemistry and Sustainable Technology

View full text Add to dashboard Cite

The transition from today's fossil-based economy to a sustainable economy based on renewable biomass is driven by the concern of climate change and anticipation of dwindling fossil resources. Although biofuels are the central theme of the transition, biomass resources cannot completely replace petroleum. It is projected that biofuels can only supply up to 30 % of today's transportation fuel market even if all available domestic biomass resources are used for the production of liquid fuels. Therefore, transformation of biomass into high-value-added chemicals is advantageous to secure optimal use of the abundant, but limited, biomass resources from the economical and ecological perspective. Industry is increasingly considering bio-based chemical production as an attractive area for investment. The potential for chemical and polymer production from biomass is substantial. The US Department of Energy recently issued a report which listed 12 chemical building blocks considered as potential building blocks for the future. Organic acids (e.g., succinic, lactic, levulinic acid, etc.) are among the widely spread ''platform-molecules,'' which may be further converted into possibly derivable high-value-added chemicals. The transition from a fossil chemical industry to a renewable chemical industry will likewise depend on our ability to focus research and development efforts on the most promising alternatives. In this chapter, we review the emerging technologies on catalytic conversion of biomass to value-added organic acids in aqueous media.

show abstract

“…After the reaction, the reactor was removed from the salt bath and immediately placed in a cold-water bath to quench the reaction. Details of the typical reaction procedure are available elsewhere [9,10]. The temperature of the reactor was increased from 20 to 300°C in approximately 15 s. Thus, the time the reactor was kept in the salt bath is only an apparent reaction time; the true reaction time can be defined as the difference between the apparent reaction time and the time required to raise the temperature of reactor.…”

Section: Experimental Methodsmentioning

confidence: 99%

Production of formic and acetic acids from phenol by hydrothermal oxidation

Cao

et al. 2011

Res Chem Intermed

View full text Add to dashboard Cite

Hydrothermal technology is a core environmental-protection technique which can be used for waste water treatment and biomass conversion. In this paper a novel idea, alkaline hydrothermal oxidation, is proposed for producing formic and acetic acids from wastewater containing phenolic compounds. The effects of the most important conditions-reaction temperature, reaction time, oxygen supply, and type of alkaline catalyst-on yields of formic and acetic acids were investigated. The results indicated that the optimum conditions for production of formic and acetic acids were: reaction temperature 300°C, reaction time 90 s, H 2 O 2 equivalent to 60% oxygen, and NaOH concentration 1.5 mmol. Under the optimum conditions the yields of formic and acetic acids reached 4.8 and 23.5%, respectively. In addition, the effect of different alkalis on yields of formic and acetic acids was also investigated. The results showed that compared with use of NaOH addition of KOH had a more pronounced effect on improving the yield of acetic acid. This research indicated that high-value-added formic and acetic acids can be recovered as resources by hydrothermal oxidation of phenolic wastewater, and thus hydrothermal oxidation has high potential for converting phenolic compounds in wastewater into value-added products.

show abstract

Impact of phenolic compounds on hydrothermal oxidation of cellulose

Cited by 25 publications

References 9 publications

Bioconversion of lignocellulosic biomass: biochemical and molecular perspectives

Bioconversion of lignocellulosic biomass: biochemical and molecular perspectives

Catalytic Conversion of Lignocellulosic Biomass to Value-Added Organic Acids in Aqueous Media

Production of formic and acetic acids from phenol by hydrothermal oxidation

Contact Info

Product

Resources

About