Abstract: A high amylose rice mutant Goamy2 and its wild type Ilpumbyeo were used to analyze starch pasting properties and structure. There were considerable differences in physicochemical characters and pasting properties between the high amylose mutant Goamy2 and its wild type Ilpumbyeo, as well as their water soluble and insoluble starch structure according to the results of Size Exclusion Chromatography(SEC). The cold water soluble components of rice flour of the mutant Goamy2 were mainly smaller molecules with the degree of polymerization(DP) of DP141 to DP2. The cold water soluble components of the wild type Ilpumbyeo were bigger molecules and the proportion of branched chains with the degree of polymerization of DP4100 to DP64 was high(33.3%). The hot water soluble starch of Goamy2 were mainly amylose, and the ratio of amylose to amylopectin was 4∶1 approximately, whereas for the hot water soluble starch of Ilpumbyeo, amylose and amylopection were both nearly a half. The ratios of long chains to short chains in hot water soluble amylopectin of the mutant and the wild type varied, being 0.67 and 0.32, respectively. The hot water insoluble starch of both two varieties were mostly amylopectin, and the proportion of amylose were less than 5%. The chain of the hot water insoluble amylopectin in the wild type was mainly short chains, with a proportion of short chains of 72.5%, whereas for the mutant, the proportion of long chains was close to the proportion of short chains.

Key words: rice, mutant, pasting property, water soluble starch, water in soluble starch, starch structure

摘要： 以高直链淀粉及突变体材料Goamy2及其野生型亲本Ilpumbyeo米粉为材料，比较了它们在理化性质和糊化特性上的差别，并通过体积排阻色谱(Size Exclusion Chromatography,SEC)分析其水溶性和不溶性淀粉组成结构差别。从冷水溶性成分来看，Goamy2主要以小分子DP141~DP2（DP为聚合度）为主，而Ilpumbyeo中带分支的链DP4100~DP64也就是相对大分子所占的比例较高，达到33.3%。从热水溶性淀粉成分来看，突变体Goamy2直链淀粉和支链淀粉的比例大致为4∶1，而Ilpumbyeo直链淀粉和支链淀粉比例大致为1∶1。至于两个材料的热水溶性支链淀粉链长分布，长短链比例差别较大，Goamy2长短链比率为0.67，而Ilpumbyeo为0.32。从热水不溶性成分来看，两个材料均以支链淀粉为主，直链淀粉所占的比例很低，均不到5%。热水不溶性支链成分的链长分布中，野生型亲本Ilpumbyeo以短链为主，短链所占的比例高达725%，而突变体Goamy2短链和长链几乎各占一半。

关键词: 水稻, 突变体, 糊化特性, 冷水溶性成分, 热水溶性成分, 淀粉结构