不同LET 12C6+离子对生防菌BJ1的辐射诱变效应

选取高低两个LET点(40和60keV/m),剂量点分别为50,100,200,400,600Gy进行辐照处理,研究了生防菌的存活率与突变率的关系,抑菌谱以及活性等。结果表明,在高LET条件下,低剂量辐照就可以得到较多的突变体,并且BJ1有较高的存活率和突变谱,有利于筛选优良的正突变体。因此高LET较低LET有更为明显的辐射诱变效应。     

C离子束诱变产生甜高粱汁酒精酵母高产菌株的研究

利用100 MeV/u C离子束对高产酒精酵母菌株进行了辐照诱变的研究。 采用红四氮唑作为筛选指示剂, 得到了5株产酒能力有所提高的突变酵母菌。 利用甜高粱汁的发酵结果表明, T4突变菌株的产酒精能力比原始出发菌株提高了18.6%, 且发酵液中的残糖含量也有所降低。 随后对T4菌株在甜高粱汁中的最适宜发酵条件做了初步探索, 结果表明: 最适发酵温度和pH值分别为30 ℃和4.5。 通过10 l发酵罐的验证试验表明: 在同样发酵条件下, T4菌株的发酵率和产酒精能力都比原始出发菌株提高了12%。 Five mutants with high ability of producing alcohol were selected out by using TTC as an indicator after irradiation of the alcohol yeast with 100 MeV/u carbon ions. The fermentation experiment in sweet sorghum juice showed that the alcohol production ability of mutant T4 strain increased 18.6% compared to the control strain. The residual sugar content in the juice was decreased too. After that, the optimum fermentation conditions of the T4 strain in sweet sorghum juice were investigated. The results showed that the optimum temperature and pH value for fermentation were 30 ℃ and 4.5, respectively. The verification experiment was fermented in a 10 l bio reactor and the obtained data indicated that the fermentative rate and the ability of producing alcohol in T4 strain was higher than that in the control strain under the same fermentation condition.     

重离子辐射植物的诱变效应研究及应用

重离子生物技术已引起人们的广泛关注, 植物育种是重离子生物技术研究和应用的热点之一。 简要介绍了重离子的基本特征和在育种应用中的优势, 综述了重离子辐射对植物分子、 细胞、 个体3个水平的诱变效应研究及重离子辐射育种取得的进展。 Heavy ion biotechnology has received much attention since the mid 1980s, when the first mutagenic effect of heavy ion beams was found in rice. Since then, plant breeding is one of the focuses in heavy ion biotechnology. In this paper we outlined the recent developments in plant breeding by heavy ion beams. We introduced briefly the essential characteristics and superiority of heavy ion beams applied in plant breeding, and reviewed further the mutagenic research in three levels(e.g., molecular, cell and individual) of plants. At last, we summarized artificial mutants obtained in plants irradiated by heavy ion beams.     

~(12)C~(6+)离子束与电子束辐照对薰衣草当代诱变效应的比较

采用100 MeV的~(12)C~(6+)离子束和1.2 MeV的电子束辐照薰衣草干种子,研究了2个品种的薰衣草干种子对不同辐射源的辐照生物学效应,以期找到薰衣草干种子的最佳诱变参数。结果表明:不论是薰衣草701还是702,经~(12)C~(6+)离子辐照后,其发芽率表现为先增大后减小的趋势;经电子束辐照后,发芽率随着剂量的升高而降低,电子束辐照后的发芽率要低于~(12)C~(6+)离子束。另外,2个品种的薰衣草经~(12)C~+离子辐照后,其胚轴胚根长度以及幼苗鲜重也较电子束辐照后的大。由此可知,重离子的辐照效果优于电子束的,有利于后期筛选出新的薰衣草突变株。     

利用甜高粱汁培养面包酵母菌的实验研究

利用优质甜高粱汁代替粮食进行发酵生产的优越性已经显现, 在此基础上研究了面包酵母在甜高粱汁中的生长情况, 测定了发酵液中酵母菌的生物量、 残总糖等参数, 并在10—100 l的发酵罐中进行了培养优化实验。 结果表明, 甜高粱汁在工业化生产面包酵母菌中具有很大的潜力。As a substitute for food supplies, sweet sorghum juice with high grade has demonstrated outstanding advantage in fermentation. To obtain the optimized fermentation conditions, the growth, the bio mass of bread yeast cultured in sweet sorghum juice and total residual sugar were investigated in the paper. The fermentation was performed and optimized in a 10—100 l bio reactor. The results show that the application of sweet sorghum juice in bread yeast production is very potential.