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81.
从土壤中筛选出一株适合用甘蔗糖蜜酒精发酵液生产腐植酸的菌株H812。单因素实验和正交实验结果表明,该菌株培养的最适酒精发酵液浓度为16°Bx,最适培养条件为:时间8d、温度34℃、摇床转速200r/min、初始pH7.0、接种量12%和装液量50ml/250ml,其中温度对发酵产品影响显著。在优化的条件下,腐植酸产量为38.12 g/L,较优化前提高了148.34%。对H812菌株进行形态特征分析以及ITS序列分析,推测该菌株为曲霉属真菌。 相似文献
82.
A method is described for the enrichment of very long chain fatty acids (VLCFAs) from total fatty acids of sugar cane wax and their identification as picolinyl esters by means of liquid chromatography-mass spectrometry with atmospheric pressure chemical ionization (LC-MS/APCI). The method is based on the use of preparative reversed phase HPLC of 100 mg amounts and their subsequent identification by microbore APCI LC-MS. The combination of these two techniques was used to identify unusual saturated VLCFAs up to C(50). 相似文献
83.
果蔗叶片生理生化指标与品质性状的典范相关分析 总被引:1,自引:0,他引:1
选用果蔗(Saccharum officinarum L.)14个品种,用典范相关分析法研究不同生育期叶片生理生化指标对果蔗品质性状的影响。结果表明:分蘖期类胡萝卜素含量与蔗茎蔗糖含量,可溶性总糖含量与蔗茎含水率,可溶性总糖含量与蔗汁还原糖含量均呈正相关;伸长初期叶绿素含量、CAT活性与蔗茎蔗糖含量,可溶性蛋白质含量与蔗茎纤维含量均呈正相关;伸长盛期Mg^2+ -ATP酶活性与蔗茎纤维含量,可溶性总糖含量与蔗茎蔗糖含量呈正相关,C/N与蔗茎含水率呈负相关;成熟期类胡萝卜素含量与蔗茎蔗糖含量呈正相关,可溶性总糖含量与蔗汁还原糖含量呈负相关。 相似文献
84.
Ki Moon Park Min Woo Song Jae Heung Lee 《Biotechnology and Bioprocess Engineering》2008,13(2):197-203
Batch culture kinetics of the red yeast, Xanthophyllomyces dendrorhous SKKU 0107, revealed reduction in biomass with glucose and lower intracellular carotenoid content with fructose. Figures were
different when compared to sucrose, which is a disaccharide of glucose and fructose. In contrast, specific growth rate constant
stayed between 0.094~0.098 h−1, irrespective of the carbon sources employed. Although the uptake rate of glucose was found to be 2.9-fold faster than that
of fructose, sucrose was found to be a more suitable carbon source for the production of carotenoids by the studied strain.
When sugar cane molasses was used, both the specific growth rate constant and the intracellular carotenoid content decreased
by 27 and 17%, respectively. Compared with the batch culture using 28 g/L sugar cane molasses, fed-batch culture with the
same strain resulted in a 1.45-fold higher cell yield together with a similar level of carotenoid content in X. dendrorhous SKKU 0107. 相似文献
85.
86.
Fornazier Ricardo F. Ferreira Renato R. Pereira Guilherme J. G. Molina Silvia M. G. Smith R. John Lea Peter J. Azevedo Ricardo A. 《Plant Cell, Tissue and Organ Culture》2002,71(2):125-131
Catalase (CAT) and superoxide dismutase (SOD) are antioxidant enzymes which are important in the metabolism of reactive oxygen species (ROS), and can be induced by environmental stresses including cadmium (Cd), a heavy metal toxic to living organisms. Sugar cane (Saccharum officinarumL.) in vitro callus cultures were exposed to CdCl2 and the activities of CAT and SOD were analysed. Lower concentrations of CdCl2, such as 0.01 and 0.1 mM caused a significant increase in callus growth, whereas 0.5 and 1 mM CdCl2 strongly inhibited growth of the callus cultures, but only after 9 days of CdCl2 treatment. Red-brown patches were also observed in calluses exposed to 0.5 and 1 mM CdCl2. Calluses grown in 0.01 and 0.1 mM CdCl2 did not exhibit any changes in CAT activity even after 15 days of growth in the presence of CdCl2. However, for calluses grown in higher concentrations of CdCl2 (0.5 and 1 mM), a rapid increase in CAT activity was detected, which was 14-fold after 15 days. Furthermore, up to five CAT isoforms were observed in callus tissue. Total SOD activity did not exhibit any major variation. One Mn-SOD and two Cu/Zn-SOD isoenzymes were observed in callus cultures and none exhibited any variation in response to the CdCl2 treatments. The results suggested that in sugar cane callus cultures, CAT may be the main antioxidant enzyme metabolizing H2O2. 相似文献
87.
88.
89.
糖蜜发酵生产丙酮丁醇的研究 总被引:4,自引:0,他引:4
分离选育出4株丙酮丁醇发酵菌种,分别编号为:CLS.001,002,003,004,都属厌氧核状芽孢杆菌,它们可利用糖蜜发酵产生丙酮和丁醇。经正交试验,选出最佳发酵条件。分离株CLS.004在糖蜜浓度10 ̄15BX、35 ̄38℃、pH6.8 ̄7.2条件下,发酵总溶剂的生成率和糖利用率分别可达到30%和85%以上。 相似文献
90.
酵母发酵蔗渣半纤维素水解物生产木糖酶 总被引:5,自引:0,他引:5
采用二次正交旋转组合设计研究了蔗渣半纤维素水解过程中硫酸浓度与液 固比对木糖收率的影响。回归分析表明 ,这两个因素与木糖的收率之间存在显著的回归关系。通过回归方程优化水解条件 ,当硫酸浓度 2 .4g L ,液 固 =6 .2 ,在蒸汽压力 2 .5× 10 4Pa的条件下水解 2 .5h ,10 0g蔗渣可水解生成木糖约 2 4g。大孔树脂吸附层析处理蔗渣半纤维素水解物 ,能有效地减少其中的酵母生长抑制物含量 ,显著改善水解物的发酵性能。用大孔树脂在pH 2条件下处理过的蔗渣半纤维素水解物作基质 ,含木糖 2 0 0g L ,产木糖醇酵母菌株CandidatropicalisAS2 .1776发酵 110h耗完基质中的木糖 ,生成木糖醇 12 7g L ,产物转化率 0 .6 4(木糖醇g 木糖g) ,产物生成速率 1.15g L·h . 相似文献