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Abstract: The current status and challenges associated with the production and utilization of cellulosic ethanol in Korea are reviewed in this paper. Cellulosic ethanol has emerged as a promising option for mitigating Korea’s CO2 emissions and enhancing its energy security. Korea’s limited biomass resources is the most critical barrier to achieving its implementation targets for cellulosic ethanol. Efforts to identify new suitable biomass resources for cellulosic ethanol production are ongoing and intensive. Aquatic biomasses including macroalgae and plantation wastes collected in the Southeast Asia region have been found to have great potential as feedstocks for the production of cellulosic ethanol. R&D explorations into the development of technologies that can convert biomass materials to ethanol more efficiently also are underway. It is expected that cellulosic ethanol will be in supply from 2020 and that, by 2030, its use will have effectively reduced Korea’s total gasoline consumption by 10%. [Copyright &y& Elsevier]

In this study, the chemical pretreatment method using ethanol organosolv with hydrogen peroxide was investigated to improve enzymatic saccharification of corn stover. The pretreatment method using ethanol with hydrogen peroxide in a flow-through reaction was proposed to lower the reaction severity such as the pretreatment temperature. With the same reaction time, the pretreatment process using organosolv (30 wt.% ethanol) containing 1 wt.% hydrogen peroxide at 150 °C resulted in a similar conversion yield as the result of the alkali pretreatment method using 15 wt.% aqueous ammonia at 170 °C. When corn stover was pretreated with 30 wt.% ethanol solution containing 5 wt.% hydrogen peroxide, a glucose conversion yield of 69.7 wt.% and glucose production of 23.8 g were achieved. [ABSTRACT FROM AUTHOR]

Abstract: Red algal biomass is a promising alternative feedstock for bioethanol production, due to several advantages including high carbohydrate content, growth rate, ethanol yield, and CO2 fixation ability. However, it has been known that most yeast strains can not utilize galactose, the major sugar of red algae, as efficiently it can utilize glucose. The authors report a novel ethanogenic strain capable of fermenting galactose, Saccharomyces cerevisiae. This mutant yeast strain exhibited exceptional fermentative performance on galactose and a mixture of galactose and glucose. At 120 g/L of initial galactose concentration, ethanol concentration reached 6.9% (v/v) within 36 h with 88.3% of theoretical ethanol yield (0.51 g ethanol/g galactose). The ethanol concentration and yield were higher than that for glucose at the same initial concentration. In a mixed sugar (galactose + glucose) condition, the existence of glucose retarded galactose utilization however, 120 g/L of the mixed sugar was completely consumed within 60 h at any galactose concentration. The critical inhibitory levels of formic acid, levulinic acid and 5-hydroxymethylfurfural (5-HMF) on ethanol fermentation were 0.5, 2.0, and 10.0 g/L; respectively. From this result, the ethanol fermentation efficiency of the novel S. cerevisiae strain using the galactose base of red algae was superior to the fermentation efficiency when using the wild type strain, and the novel strain was found to have resistance to the major inhibitors generated during the saccharification process. [Copyright &y& Elsevier]

Abstract: The study of bioproduct production, such as bioethanol and biochemicals, from inexpensive biomass has recently attracted considerable attention. Compared to land biomass, marine biomass can be grown rapidly and is easily cultivated without the need for expensive equipment. In addition, annual CO2 absorption by marine biomass is five to seven times higher than that of wood-biomass and the carbohydrate content is higher and can easily be converted to chemicals through proper chemical processes. In the production of various biochemicals from marine biomass, levulinic acid is a highly versatile chemical with numerous industrial uses and the potential to become a commodity chemical. It can be used as a raw material for resins, plasticizers, textiles, animal feed, coatings and antifreeze. The present study was carried out to determine the optimum conditions of temperature, acid concentration and reaction time for levulinic acid production from marine biomass Gelidium amansii using two-step treatment. In the first hydrolysis step, solid-state cellulose was obtained through acid soaking and used to produce ethanol by fermentation and liquid-state galactose. In the second hydrolysis step, the liquid-state galactose was converted into levulinic acid via a high-temperature reaction in a batch reactor. The overall production conversion of G. amansii biomass to levulinic acid in the two-step acid hydrolysis was approximately 20.6%. [Copyright &y& Elsevier]