• Journal of Life Science
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• v.15 no.1 s.68
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• pp.33-37
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• 2005

Sasa borealis Makino is distributed in East Asia such as Korea, Fushun in China, and Japan. Especially the species is only found in the high altitude (above 600 m) at mountain of cold regions including The Korean Peninsula. The level of genetic diversity and population structure of this species was surveyed using starch gel electrophoresis at putative five enzyme loci from three natural populations in Korea. Results from twelve loci indicated that genetic diversity was low. In addition, analysis of fixation indices revealed a substantial heterozygosity deficiency in some populations and loci. The reasons for the deficit of heterozygosity may be partly considered inbreeding, small population sizes, and mating of demes. S. borealis can reproduce extensively by producing rhizomes and potentially by sexually produced seeds. Rhizomes are generally long, prostate stems rooting at the nodes.

• Journal of Life Science
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• v.23 no.6
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• pp.728-735
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• 2013

Plantago asiatica (Plantaginaceae) is a wind-pollinated plant that grows mainly on fields in East Asia. Starch gel electrophoresis was used to investigate the allozyme diversity and population structure of 18 populations of this species. Although the plantain populations were isolated and patchily distributed, they maintained a high level of genetic diversity; the average percentage of polymorphic loci was 57.1%, the mean number of alleles per locus was 2.07, and the average heterozygosity for 18 populations was 0.201. The combination of a predominant wind-pollinated, mix-mating reproduction, large population sizes, high gene flow between subpopulations, and a propensity for high fecundity may explain the high level of genetic diversity within populations. A direct gradient in overall genetic diversity is associated with latitude. Genetic diversity of P. asiatica is markedly decreased from $35^{\circ}3^{\prime}$ to high latitude and decreased from $35^{\circ}3^{\prime}N$ to low latitude, whereas there does not show a longitudinal gradient in genetic diversity.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.521-527
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• 1996

Some structural characteristics of kidney bean starches (3 varieties : Pink kidney bean, Red kidney bean and White kidney bean) were investigated. The amylose content and the ${\beta}$-amylolysis limit of kidney bean starches were $32.6{\sim}34.5%$ and $69.9{\sim}71.0%$, respectively. The kidney bean amylopectin was composed of super long chain of ${\overline{DP}}$ above 60 ($5.28{\sim}12.62%$), B chain of ${\overline{DP}}$ $45{\sim}60\;(29.85{\sim}33.65%)$ and A chain of ${\overline{DP}}\;10{\sim}20(22.94{\sim}29.85%).$ The chain distribution of kidney bean starches were different from variety to variety. The acid (2.2 NHCI) hydrolysis of kidney bean starches showed, as hydrolysis time increased, the patterns of three stages. The acid hydrolysis rate and iodine reaction of acid treated starches were different from variety to variety As acid hydrolysis time increased, the amylose and the ${\alpha}$-1.6-glucosidic linkage of amylopectin of amorphous state were gradually hydrolyzed. Finally, the chain of ${\overline{DP}}$ 20 of crystalline state was left in the acid treated starches.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.44-52
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• 1996

Sensory properties of cooked rice were affected by the varieties and growing environments of the rice. Moistness, cohesiveness, and adhesiveness of cooked rice were highly and positively correlated each other, whereas firmness was negatively correlated with these attributes. Sixty rice samples which differed in varieties and/or growing environments were divided into four groups based on their textural properties through principal component analysis and cluster analysis. Quality type I showed the highest values for moistness, cohesiveness, and adhesiveness, and the lowest values for firmness of cooked rice. On the other hand, quality type IV showed just the opposite values. There was no significant difference among rice starches in amylose content (P<0.05). A17 (type III) and A09 (type IV) had higher blue values for starch and amylopectin than the other samples (type I and II). On the amylogram, these samples showed lower values for breakdown and higher values for setback than the other samples. Average degree of polymerization, average chain length, and average number of chains for amylose and amylopectin were 597-878 and 2660-3140, 140-230 and 17-19, and 3.1-4.9 and 140-170, respectively.