排序方式: 共有87条查询结果,搜索用时 750 毫秒
81.
An on-line device, ORP (oxidation-reduction potential)-stat, was used to control glucose-feeding for enhancing xylitol conversion from D-xylose during an oxygen-limited fermentation by Candida tropicalis. The fermentation was carried out in a 5 l jar fermenter. After glucose in the medium was depleted, a switching to a limited aeration and feeding glucose controlled by ORP-stat was performed. The maximum xylitol yield was obtained under a condition at an ORP of -180 mV and at an aeration rate of 0.2 l min(-1). 相似文献
82.
Attilio Converti Patrizia Perego Paolo Torre Silvio Silverio da Silva 《Biotechnology letters》2000,22(23):1861-1865
Xylose production by Candida guilliermondii FTI 20037 was carried out in a synthetic medium in the presence of 0–100 g methanol l–1, 0–0.7 g furfural l–1 or 0–1.3 g acetic acid l–1. Kinetic results show a mixed inhibition mechanism in all three cases. Maximum specific productivity and saturation constant for product formation were, in the absence of inhibition, 3.6 gP gX
–1 h–1 and 232 gS l–1, respectively, while the inhibition constants, K
i and K
i, were 17 and 50 g methanol l–1, 0.62 and 7.0 g furfural l–1, 0.69 and 3.5 g acetic acid l–1, which suggests the following order of inhibition: furfural > acetic acid > methanol. 相似文献
83.
84.
该文研究了木糖、木糖醇对木聚糖酶Shearzyme 500L酶解蔗渣木聚糖的影响。通过热带假丝酵母(Candida tropiclis)转化酶解副产物木糖,解除木糖对木聚糖酶的抑制作用,从而获得高木二糖含量的低聚木糖。结果表明:木糖是Shearzyme 500L的酶活性抑制物,其抑制作用与溶液中的木糖量成正比;木糖醇对木聚糖酶无抑制作用;热带假丝酵母可将蔗渣木聚糖酶解液中的木糖转化为木糖醇而不利用低聚木糖,木二糖占总糖比例由53.09%升高到62.92%,经二次酶解后,木二糖比例可达78.90%。 相似文献
85.
Pan-Soo Kim Hyun-Dong Shin Joong-Kon Park Yong-Hyun Lee 《Biotechnology and Bioprocess Engineering》2000,5(3):174-180
Cyclodextrin glucanotransferase (CGTase) fromThermoanaerobacter sp. was adsorbed on the ion exchange resin Amberlite IRA-900. The optimum conditions for the immobilization of the CGTase
were pH 6.0 and 600 U CGTase/g resin, and the maximum yield of immobilization was around 63% on the basis of the amount ratio
of the adsorbed enzyme to the initial amount in the solution. Immobilization of CGTase shifted the optimum temperature for
the enzyme to produce transglycosylated xylitol from 70°C to 90°C and improved the thermal stability of immobilized CGTase,
especially after the addition of soluble starch and calcium ions. Transglycosylated xylitol was continuously produced using
immobilized CGTase in the column type packed bed reactor, and the operating conditions for maximum yield were 10% (w/v) dextrin
(13 of the dextrose equivalent) as the glycosyl donor, 10% (w/v) xylitol as the glycosyl acceptor, 20 mL/h of medium flow
rate, and 60°C. The maximum yield of transglycosylated xylitol and productivity were 25% and 7.82 g·L−1·h−1, respectively. The half-life of the immobilized CGTase in a column type packed bed reactor was longer than 30 days. 相似文献
86.
Keitaro Kiyosawa 《Physiologia plantarum》1993,88(2):366-371
The permeability of internodal cells of Chara australis R. Brown for polyol molecules was determined by using a turgor balance to measure the increase in the osmotic pressure of an internodal cell incubated in artificial pond water containing one of the polyol compounds tested. The permeabilities for ethylene glycol, glycerol, meso -erythritol, xylitol and mannitol were (4. 39 ± 0. 52) × 10−9 , (1. 49 ± 0. 40) × 1010 , (4. 92 ± 0. 27) × 10−10 (9. 9 ± 3. 4) × 1011 and (7. 6 ± 4. 8) × 10−12 m s−3 , respectively. The permeability for glycerol was slightly smaller than that for meso -erythritol, whose molecular weight is larger than that of glycerol in this homologous series: but the reason for this is not clear. 相似文献
87.
罗明典 《中国生物工程杂志》2001,21(4):51-53
本文讨论了微生物发酵产品如乙醇、甲醇、甘油、木糖醇和肌醇等的利用和开发前景,并强调了现代生物技术与常规生物技术相结合为选育高效菌株的重要性 。 相似文献