【作者】 王莉娟；

【导师】 王卫卫；

【作者基本信息】 西北大学 ， 微生物学， 2009， 硕士

【摘要】 近年来,人们对油脂尤其是功能性油脂的需求量急剧上升。与此同时,石化油脂迅速枯竭,而植物油脂因受其产地和气候的影响,并不能满足社会日益增长的需要。因此,微生物油脂以其独特的优势被许多国家的研究者所重视。本文以被孢霉为研究菌株,主要研究了以下三方面的内容:1.考察了发酵过程中温度、接种量、溶氧量、pH值等因素对被孢霉发酵生产油脂的影响。确定最佳发酵温度为前期28℃,培养后期也就是第144h时将温度调为20℃发酵一天;接种量为5%;装液量20%,pH值5.0～6.0,在上述发酵条件下,油脂含量为46.31%。在对培养基优化的基础上,通过向发酵液中添加不同激活剂,筛选出了两种促进作用明显的激活剂丙酸钠和甘草酸,使被孢霉油脂含量分别提高到60.12%和73.13%。2.其次,通过超临界二氧化碳萃取装置大量萃取被孢霉油脂,考察了原料粒度、温度、压力、时间四种因素对油脂萃取率的影响,发现当温度40℃、压力20 Mpa、时间120 min、原料粒度20～40目为油脂的最佳萃取条件。在此条件下,油脂得率43.08%,气相色谱分析结果显示油脂中棕榈酸占24.2%、油酸54.2%、亚油酸11.3%、γ-亚麻酸2.8%。3.最后,还对所得到的油脂进一步精炼,对微生物油脂制备生物柴油的过程进行了初步的探索,考察了油脂精炼和甲酯化制备生物柴油过程中的一些因素的影响,为用被孢霉发酵生产生物柴油提供了科学依据。更多还原

【Abstract】 For the past few years, peoples demand of oil especially the functional oil rapidly ascend.Meanwhile, petroleum exhausted in short order, and plant oil cannot meet the increasingly need of society because of the influence of manufacturing location and climate. So microorganism oil are payed attention to by researcher from many countries for it’s particular dominant.This artical product microorganism oil by fermentation of Mortierella, investigated three details below:1. inspected inlfulence of temperature, inoculation, ventilate, pH on oil produnct in the process of fermentation. Definite that the fermentate temperature is 28℃in the preceeding time and 20℃in the later period i.e. the 144th hours for ong day. Inoculation 5%, dissolved oxygen 20%, pH5.0～6.0, and in this condition, oil content 46.31%. fundamentally, through add different activations into the ferment fluid, screened out screen out two activation （sodium propionate and glycyrrhizic acid） that promoted the oil content obviously, and the oil content reached 60.12% and 73.13% seperatively.2. Soon extract oil in Mortierella by supercritical CO₂ equipment, surveyed the influence on extraction yield of four factor partical size of raw material,temprature, pressure, time. Find that the best extraction condition is 40℃, 20Mpa, 120min, 20～40 item, and in this condition, the oil content is 43.08%, gas chromatography analysis outcomes show that hexadecanoic acid account for 24.2%, oleic acid account for 54.2%, linoleic acid reached 11.3%,γ-linolenic acid account for 2.8% in the oil.3. further refined the oil, probed the process that preparation bio-diesel by microorganism oil preliminary. Supplyed scientific basis for producting biosel by fermentation of Mortierella.更多还原