毕业论文移动版

摘要:1-脱氧野尻霉素（DNJ）是一种哌啶生物碱，具有抑制α-葡萄糖苷酶，能抑制糖吸收、降低血糖、抗肿瘤转移、抗病毒等，这种高效的α-糖苷酶抑制剂，也能够用于治疗艾滋病，高雪氏病和糖尿病等疾病。目前研究人员已经能够从天然植物来源（桑叶）中提取制备DNJ，然而从桑叶中提取获得的DNJ产量很低而且制备成本很高。根据文献报道某些芽孢菌株和链霉菌属菌株可以产DNJ，所以研究者致力于从DNJ的微生物来源方面获取DNJ，通过微生物发酵的方式为工业化大规模生产DNJ奠定基础。在本研究中，通过分子生物学方法实验从永川豆豉、刘派楼豆豉、干豆豉中筛选产DNJ的菌株分离了4株菌株，并用16SrDNA的方法对产DNJ菌株进行种属鉴定，鉴定结果为枯草芽孢杆菌(Bacillussubtilis）。通过测定发酵温度(30℃、35℃、37℃)、时间、碳源(葡萄糖、山梨醇)等条件下菌株产DNJ的浓度，最高可达到0.73µg/mL，从而确定菌株产DNJ的最佳发酵条件为发酵温度35℃，发酵时间48h或72h，碳源为山梨醇，为今后大规模发酵产DNJ提供参考。

关键字：豆豉；1-脱氧野尻霉素;芽孢杆菌；

Abstract:1-deoxynojirimycin (DNJ) is a kind of piperidine alkaloid that have a  strong inhibitory effect on α-glucosidase. As the inhibition of α-glucosidase activity improves the sugar uptake and decreases the blood glucose level. It also plays a role in anti-tumor metastasis and antiviral activity. DNJ has been mainly isolated from the root and leaf of the mulberry tree. However, the yield of DNJ from mulberry leaves is low and the cost is high. According to the literature, several species such as Bacillus sp. , Streptomyces sp., are known to produce DNJ. There is thus an urgent need to develop an alternative DNJ production method such as by microbial fermentation. Several studies have therefore investigated the production of DNJ by using microbial fermentation. In this study, four strains producing DNJ were isolated from Chinese Traditional Food-Yongchuan, Liupailou and dried douchi by PCR method. The strains were identified by 16S rDNA sequences. The maximum concentration of DNJ were optimized by shake flask through  optimization of the fermentation temperature (30 ℃, 35 ℃, 37 ℃), fermentation time, carbon source (glucose, sorbitol) and nitrogen source. The optimum conditions were as follows: fermentation temperature 35 ℃, fermentation time 48 h or 72 h, carbon source is sorbitol, DNJ production is 0.73 µg/mL. It lay the foundation for the  future large-scale fermentation for the DNJ production.

Keywords： Douchi，1-Deoxynojirimycin，Bacillus sp.

目录

第一章绪论 1

1.1引言 1

1.2DNJ的来源 1

1.2.1动物来源 1

1.2.2植物来源 2

1.2.3微生物来源 3

1.3DNJ的提取方法 4

1.3.1水提取法 4

1.3.2有机溶剂提取法 4

1.3.3微波提取法 5

1.3.4超声提取法 5

1.3.5超临界萃取法 5

1.3.6生物酶法提取 6

1.4DNJ的作用 6

1.4.1DNJ的降血糖作用 6

1.4.2DNJ对病毒活性的抑制作用 7

1.4.3DNJ对肿瘤转移的抑制作用 7

1.5微生物发酵 (责任编辑：qin)