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11.
H. Kato-Noguchi 《Biologia Plantarum》1999,42(3):445-449
Two forage grasses, timothy (Phleum pratense L.) and ryegrass (Lolium multiflorum Lam.) were exposed to flooding, and activities
of alcohol dehydrogenase (ADH) and their isozyme profiles were determined. The flooding stress increased ADH activities in
both species. This increase was 2-times greater in timothy than in ryegrass. Only one ADH isozyme was found in non-flooded
seedlings of both species, whereas two and four bands were identified in ryegrass and timothy seedlings, respectively, under
flooding stress.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
12.
《Bioscience, biotechnology, and biochemistry》2013,77(7):1146-1147
Pseudomonas sp. strain ST-200 isolated from a humus soil effectively oxidizes cholesterol dissolved in organic solvents but not that suspended in the growth medium. The organism does not assimilate cholesterol. This organism oxidized a variety of 5α- or 5-ene-sterols dissolved in organic solvent. First, the 3β-OH group was oxidized to a ketone group. The 3α-OH group was scarcely oxidized. Successively, C-6 position of 5-ene-steroids was hydroxylated, and a double bond of 5-ene-steroids was transferred from Δ5 to Δ 4. Then, the 6-OH group was oxidized to a ketone group. Persolvent fermentation with ST-200 would provide an effective, convenient, and stereospecific method to oxidize the C-3 and C-6 positions of steroids. 相似文献
13.
14.
The effects of the specific growth rate and methanol concentration on the degradation of hirudin produced by recombinant Pichia pastoris were investigated. When a methanol-limited state and the specific growth rate of 0.02 h–1 were maintained during the fermentation, a minimum degradation of hirudin and a maximum specific hirudin production rate were achieved. By this strategy, the production of intact recombinant hirudin Hir65 reached 0.7 g l–1 in fed-batch fermentation. Its proportion was 35% to all forms of hirudin. 相似文献
15.
The simultaneous action of shear deformation and high pressure (SDHP) creates changes in the structure of wood and its main
components (cellulose, hemicelluloses, lignin). The formation of water and alkali soluble polysaccharides under SDHP action,
proceeds in seconds in the solid state, without the use of any reagents and solvents. Therefore, SDHP seems to be a technologically
safe method and friendly to the environment. The amorphization of cellulose crystallites and depolymerization of cellulose
chains were observed under a wide range of pressures (1–6 GPa), both for cellulose samples and the cellulose part of wood.
Similar depolymerization occurs in the hemicellulose part of wood. The decomposition of polysaccharides under SDHP causes
the formation of the water soluble part, whose content increases with pressure and the applied shear deformation. A maximum
solubility of 40% and 55% was registered at 6 GPa following treatment of cellulose and birch wood samples. A higher output
in the case of wood can be explained by a specific role of lignin under SDHP, which acts as a ‘grinding stone’ during cellulose
and hemicelluloses destruction. As shown by high-performance size exclusion chromatography, the water soluble fraction obtained
from cellulose contained glucose (2.6%), cellobiose (9.6%), cellotriose (16.6%) and other higher water soluble oligomers (71%).
Almost complete dissolution (98%) of the treated cellulose sample can be achieved by extraction with 10% NaOH solution. The
SDHP treated birch wood was subjected to submerged fermentation (with Trichoderma viride), and a 13% output of proteins was
obtained. In this case, the water soluble part played the role of the so called ‘start sugars’. Abbreviations: ASF, alkali
soluble fraction; DP, degree of polymerization; EC, energy consumption; HP, high pressure; LMWS, low molecular weight sugars;
MC, moisture content; MCC, microcrystalline cellulose; SD, shear deformation, SDHP, shear deformation under high pressure;
SS, shear strength; WSF, water soluble fraction
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
16.
M. Moniruzzaman 《World journal of microbiology & biotechnology》1995,11(6):646-648
The xylose in an enzymatic hydrolysate of steam-exploded rice straw was not consumed by Pichia stipitis until the glucose was almost exhausted. A diauxic lag of 2 to 3 h in both cell growth and ethanol production occurred as metabolism switched from glucose to xylose utilization. Ethanol production was maximal [6 g ethano/l from 15 g reducing sugars/l (78% theoretical yield)] at an aeration rate of 0.2 vol/vol. min.The author was with the Department of Chemical Engineering, Kanazawa University, Kanazawa 920, Japan, but is now with the Engineering Biosciences Research Center, Cater-Mattil Hall, The Texas A&M University System, College Station, Texas 77843-2476, USA. 相似文献
17.
An Improved CARV Process for Bioethanol Production from a Mixture of Sugar Beet Mash and Potato Mash
《Bioscience, biotechnology, and biochemistry》2013,77(3):602-604
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. An energy-consuming thick juice preparation from sugar beet for concentration and sterilization was omitted in this new process. 相似文献
18.
Aspects Affecting Biosynthesis and Biotransformation of Secondary Metabolites in Plant Cell Cultures
《Critical reviews in biotechnology》2013,33(2):105-118
AbstractBiosensors are useful analytical devices that can be integrated with on-line process monitoring schemes. In this article, the principles and applications of these devices for bioprocess monitoring are considered. Several different types of biosensors are described, and the applications and limitations of flow injection analysis (FIA) for these applications are discussed. It is hoped that the background provided here can be useful to researchers in this area. 相似文献
19.
《Bioscience, biotechnology, and biochemistry》2013,77(7):1596-1600
Saccharomyces cerevisiae is the main microorganism used in wine brewing, because this microbe has potent ability to produce alcohol dehydrogenase. We have recently discovered that some genera of mushroom produced alcohol dehydrogenase, and made wine by using a mushroom in place of S. cerevisiae. The highest alcohol concentration in this wine was achieved with Pleurotus ostreatus (2.6 M, 12.2%). In the case of Agaricus blazei, the same alcohol concentration (1.7 M, 8%) was produced under both aerobic and anaerobic conditions. This wine produced by A. blazei contained about 0.68% β-D-glucan, which is known to have a preventive effects against cancer. The wine made by using Flammulina velutipes showed thrombosis-preventing activity, giving a prolonged thrombin clotting time 2.2-fold that of the control. Thus, the wine made by using mushroom seems to be a functional food which can be expected to have preventive effects against cancer and thrombosis 相似文献
20.
《Journal of Plant Interactions》2013,8(3):169-174
Abstract A psychrotolerant, halotolerant and alkalophilic yeast was isolated from fermented leaves of Camellia sinensis Kuntze, the tea plant. The yeast strain, named Tea-Y1, was both phenotypically and genotypically identified as belonging to the species Debaryomyces hansenii. This assignment was confirmed by scanning and transmission electron microscopy. The analysis of growth curves demonstrated the ability this yeast strain to grow in a temperature range between 4°C and 28°C, with an optimum of 23°C. The ecology of this yeast in the C. sinensis phyllosphere, as well as its possible role in tea fermentation and storage, with particular reference to iced tea, are discussed. 相似文献