This study assessed the effects of dietary supplementation of poly-β-hydroxybutyrate (PHB) on growth performance, feed efficiency, non-specific immunity, digestive enzyme capacity, phagocytic activity, hemocyte count, intestinal morphology, and disease resistance against Vibrio parahaemolyticus of Pacific white shrimp (Penaeus vannamei). Six diets were prepared by supplementing graded levels of PHB at 0.00, 0.
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 objective of this study was to develop an efficient production system for cellulase preparation with a high level of xylanolytic enzymes using soluble carbon sources. When xylose and arabinose were simultaneously fed with glucose and cellobiose, a mutant of Trichoderma reesei, M3-1, showed sufficient levels of cellulolytic and xylanolytic activities, indicating that xylose and arabinose are good inducers for the production of xylanolytic enzymes. In a continuous feeding experiment using glucose/cellobiose and glucose/xylose/cellobiose, cellulase preparations with various levels of xylanolytic enzymes were obtained by altering the feeding solutions and the timing of their addition.
View Article and Find Full Text PDFThe RT-CaCCO process for enzymatic saccharification was applied to readily-milled fractions of wet sugarcane bagasse. Wet bagasse immediately after juice extraction was crushed with shark-mill blades to prepare two fractions referred to as readily-milled (RF) and hardly-milled fraction (HF). Monosaccharide recoveries from RFs via the RT-CaCCO process were 1.
View Article and Find Full Text PDFA mutant Cs3512, which showed better fermentation of xylose and the mixtures of xylose and glucose, was obtained through mutation of Candida shehatae ATCC 22984 and screening with a medium containing antimycin A and TTC (2,3,5-triphenyltetrazolium chloride). Cs3512 produced 44.4 g/l of ethanol from 121.
View Article and Find Full Text PDFA simple process (the direct-saccharification-of-culms (DiSC) process) to produce ethanol from rice straw culms, accumulating significant amounts of soft carbohydrates (SCs: glucose, fructose, sucrose, starch and β-1,3-1,4-glucan) was developed. This study focused on fully mature culms of cv. Leafstar, containing 69.
View Article and Find Full Text PDFIn order to establish an efficient bioethanol production system from rice straw, a new strategy to ferment the mixture of glucose and xylose by a sequential application of Saccharomyces cerevisiae and Pichia stipitis was developed, in which heat inactivation of S. cerevisiae cells before addition of P. stipitis was employed.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
August 2011
A mixed mash of sugar beet roots and potato tubers with a sugar concentration of 23.7% w/v was used as a feedstock for bioethanol production. Enzymatic digestion successfully reduced the viscosity of the mixture, enabling subsequent heat pretreatment for liquefaction/sterilization.
View Article and Find Full Text PDFWe improved the CaCCO process for rice straw by its incorporation with a step of lime pretreatment at room temperature (RT). We firstly optimized the RT-lime pretreatment for the lignocellulosic part. When the ratio of lime/dry-biomass was 0.
View Article and Find Full Text PDFA Gram-positive bacterium, N52, that produces intracellular glucan from l-arabinose, was isolated from soil and identified as Sporosarcina sp. according to rRNA gene sequence analysis and physiological/biochemical characterizations. Glucan production by N52 increased significantly in the exponential phase of aerobic liquid culture and was maintained at the highest level during the stationary phase, reaching 37.
View Article and Find Full Text PDFRice plants are known to accumulate starch in leaf sheaths and culms, and in some cultivars significant amounts of starch are present at the mature stage. This can be considered as potential feedstock for the recovery of fermentable sugars. We isolated starches from the culms of cultivars Yumeaoba, Koshihikari, and Leafstar to investigate their structural and physical features.
View Article and Find Full Text PDFAppl Microbiol Biotechnol
August 2010
From 22,791 mutants of a cellulase hyper-producing strain of Trichoderma reesei (Hypocrea jecorina), ATCC66589, as the parent, we selected two mutants, M2-1 and M3-1, that produce cellulases in media containing both cellulose and glucose. The mutation enabled the mutants to produce cellulases, which were measured as p-nitrophenyl beta-D: -lactopyranoside-hydrolyzing activities, in media with glucose as a sole carbon source, although M2-1 exhibited different sensitivities to glucose from M3-1. When the mutants were grown for 8 days on a medium with cellulose as a sole carbon source, the filter-paper-degrading activities (FPAs) per gram of cellulose were 257 and 281 U for M2-1 and M3-1, respectively, values that were 1.
View Article and Find Full Text PDFIn order to establish an efficient bioethanol production system for rice straw, we developed a novel lime-pretreatment process (CaCCO process) that did not require a solid-liquid-separation step. This process adopted a step in which after pretreatment lime was neutralized by carbonation, resulting in a final pH of about 6. CaCO(3) produced by the process was kept in the reaction vessel, and no significant inhibitory effects on enzymatic saccharification and fermentation were observed.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
April 2010
Rice straw was manually dissected and two main fractions were recovered: a culm and a leaf sheath/blade fraction, in order to evaluate their potential as feedstocks for the recovery of fermentable sugars. In the case of cv. Koshihikari and Milkyqueen, most soft carbohydrates (SCs: glucose, fructose, sucrose, starch, and beta-1,3-1,4-glucan) were present in the culms, reaching 47.
View Article and Find Full Text PDFSoft carbohydrates, defined as readily-recoverable carbohydrates via mere extraction from the biomass or brief enzymatic saccharification, were found in significant amounts in rice straw as forms of free glucose, free fructose, sucrose, starch, and beta-1,3-1,4-glucan. In this study, we investigated their amounts in rice straw (defined as culm and leaf sheath), and developed an easy method for glucose and fructose recovery from them with heat-pretreatment and subsequent 4-h enzymatic saccharification with an enzyme cocktail of cellulase and amyloglucosidase. The recovery of glucose and fructose exhibited good correlation with the amounts of soft carbohydrates.
View Article and Find Full Text PDF