(ER) is greatly appreciated among domestic energy crops in Japan for the production of fermentable sugars from lignocellulosic polysaccharides. In this study, we developed an efficient Ca(OH)-based pretreatment of both stems and leaves of ER at ambient temperature with the addition of a washing step for enzymatic saccharification. The recoveries of glucans and xylans in the pretreated ER after four countercurrent washing cycles were 91 and 76 %, respectively, the former being considerably higher than that of rice straw (RS) (72 %).
View Article and Find Full Text PDFSorghum bagasse samples from two sets (6 and 6; 18 and 18) of wild-type and corresponding "brown midrib" () mutant strains of sweet sorghum were evaluated as the feedstock for fermentable sugar recovery the calcium capturing by carbonation (CaCCO) process, which involves Ca(OH) pretreatment of bagasse with subsequent neutralization with CO for enzymatic saccharification. Saccharification tests under various pretreatment conditions of the CaCCO process at different Ca(OH) concentrations, temperatures or residence periods indicated that strains are more sensitive to the pretreatment than their counterparts are. It is expected that variant 6 is more suitable for glucose recovery than its wild-type counterpart because of the higher glucan content and better glucose recovery with less severe pretreatment.
View Article and Find Full Text PDFThe effect of lime pretreatment of brown midrib sorghums on enzymatic saccharification was investigated. Under most of the pretreatment conditions, the saccharification yields of bmrs were higher than those of the normal counterparts. This result suggests that bmr is useful to reduce pretreatment costs, because the amount of lime necessary for the pretreatment of biomass can reduced by using bmr mutants.
View Article and Find Full Text PDFWe evaluated genetic variations in the non-structural carbohydrate (NSC) and the cell-wall components of stem in rice, sorghum, and sugar cane to assess the potential suitability of these gramineous crops for bioethanol production. For NSC, the maximum soluble sugar concentration was highest in sugar cane, followed by sorghum with sucrose. The major NSC in rice was starch, but there were wide variations in the starch to soluble sugar ratios among the cultivars.
View Article and Find Full Text PDFA low temperature alkali pretreatment method was proposed for improving the enzymatic hydrolysis efficiency of lignocellulosic biomass for ethanol production. The effects of the pretreatment on the composition, structure and enzymatic digestibility of sweet sorghum bagasse were investigated. The mechanisms involved in the digestibility improvement were discussed with regard to the major factors contributing to the biomass recalcitrance.
View Article and Find Full Text PDFRed clover (Trifolium pratense L.) is a diploid (2n = 14), self-incompatible legume that is widely cultivated as a forage legume in cold geographical regions. Because it is a short-lived perennial species, improvement of plant persistency is the most important objective for red clover breeding.
View Article and Find Full Text PDFThe possibility of using two kinds of sorghum as raw materials in consolidated bioprocessing bioethanol production using Flammulina velutipes was investigated. Enzymatic saccharification of sweet sorghum was not as high as in brown mid-rib (bmr) mutated sorghum, but the amount of ethanol production was higher. Ethanol production from bmr mutated sorghum significantly increased when saccharification enzymes were added to the culture.
View Article and Find Full Text PDFIn a search for cold-regulated genes that are differentially expressed in alfalfa genotypes of contrasting freezing tolerance, we screened 1036 arrayed cDNA clones. The screening resulted in isolation of cDNA clones, which demonstrated dramatic differences in expression between hardy and un-hardy alfalfa varieties. Detailed analysis revealed that these cDNAs represent parts of novel non-coding repetitive elements carrying long-terminal repeats (LTR) and other retroelement-like features.
View Article and Find Full Text PDFThis study describes a rapid and simple way to amplify limited amounts of probes used for cDNA array hybridization while maintaining the original representation of transcripts in the samples. The approach is based on linear amplification of cDNA-coupled controlled extension of amplified products and yielded a 50-75-fold increases in hybridization signal intensity. Controlled extension of products is achieved either by adjusting the amplification conditions or by using a digested template.
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