• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.597-603
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• 2002

The analysis of traditional process for a Korean puffed rice snack (Yukwa) is needed to develop an advanced process for Yukwa-making. Steeping and punching (Koarichigi) processes, consume time and labor in Yukwa-making, were analyzed on this study. Steeping of waxy rice at $15^{\circ}C$ for 3 days was required to equilibrate moisture absorption in waxy rice kernel. However, steeping for more than 6 days was required soft texture and small air cell distribution of Yukwa. Protein content at pericarp on endosperm of waxy rice kernel was decreased and starch granule was damaged during steeping. RVA paste viscosity was the highest at 6 day steeping after than decreased. Expansion ratio of Yukwa was increased with the increase in steeping time. Air bubbles in dough after punching were uniformly distributed and kneading energy input was decreased with the increase in steeping time. Soft texture, unique texture of Yukwa could be controlled by controlling steeping time and kneading energy input during punching process.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.289-298
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• 2023

Stored rice grain undergoes physical and chemical deteriorations over time. As temperature and moisture content are important factors affecting to the denaturation of rice, it is important to store rice at a low temperature and hermetic condition. From a microscopic point of view, many studies have already reported how proteins and lipids were denatured within rice grain. Meanwhile, the weight loss of rice is currently observed at actual storage sites and can occur for diverse reasons. In this study, it was assumed that the decomposition process of polysaccharides, known as the main component of rice, plays an important role in its weight loss. In specific, the roles of enzymes were also evaluated. Our interest is in the major polysaccharides within a rice grain such as starch as well as within a rice endosperm cell wall. It is suspected that the weight loss of rice grains during storage seems to associate with the degradation of amylose and amylopectin. Nevertheless, it should be also speculated the correlating effect of other components such as proteins and lipids.

• Korean Journal of Medicinal Crop Science
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• v.2 no.1
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• pp.81-85
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• 1994

This experiment was carried out to investigate the fertilization and the size of mature female and male gametophytic parts of Pulsatilla koreana after artificial pollination. The size of pollen is $26.5{\mu}m$ at the time of anther dehiscence, that is, about $3{\sim}4$ days after pollination. Synergid nucleus, egg nucleus, and polar nucleus are 10.0, 15.0, and $32.5{\mu}m$ respectively at the time of completing egg apparatus formation, that is, about 2 days after pollination. Poller tubes germinate on stigma about 10 hours, passing lower part of style about 30 hours, penetrating into micropyle about 35 hours after pollination. Sperm nucleus penetrates into polar nucleus about 40 hours and egg cell about 48 hours after pollination. But, there seems to be different among the individuals. Multinuclei and multinucleoli are formed in egg cell, synergid, and polar nucleus about the time of fertilization. Proembryo is formed about 4 days, being changed to large globular form about $6{\sim}8$ days after pollination. Endosperm nuclei divide into free nuclei after fertilization and change to cotyledon in gymnosperm. There seems to be same phenomena in Pulsatilla koreana.

• Korean Journal of Plant Taxonomy
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• v.42 no.4
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• pp.260-266
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• 2012

Because the embryological features of Jeffersonia dubia are poorly understood, we conducted the first embryological study comparing it to other related genera of Berberidaceae. Important embryological features of J. dubia are as follows: the anther is tetrasporangiate, anther wall formation confirms basic type, glandular tapetum cells are two nucleate, the epidermis persistent, and the endothecium develops fibrous thickenings, anther dehiscence by two valves, meiosis in a microspore mother cell is accompanied by simultaneous cytokinesis, microspore tetrads are usually tetrahedral, pollen grains two cells at the time of anthesis. The ovule is bitegmic, anatropous and crassinucellate, archesporium single celled, development of the embryo sac Polygonum type, a mature embryo sac is ellipsoidal in shape. Endosperm formation is of Nuclear type and embryogeny Onagrad type. Seeds are arillate and seed coat exotestal type. Embryological comparisons showed that Jeffersonia resemble to Epimedium and Vancouveria rather than Berberis and Mahonia in some features, like as number of tapetal cells, cytokinesis in meiosis, and thickness of exotesta. It also resembles to Gymnospermium in mode of anther wall formation, number of tapetal cells, formation of nucellar cap, and nature of antipodal cells. Nevertheless, Jeffersonia and Gymnospermium differ from several other embryological features and molecular data too. Therefore, embryological evidences support that Jeffersonia is closely related with Epimedium and Vancouveria.

• Korean Journal of Plant Taxonomy
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• v.40 no.4
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• pp.226-233
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• 2010

An intensive study of the embryology of Gymnospermium microrrhynchum was conducted to provide information regarding a discussion of the phylogenetic relationships of the genus, which is yet unstudied. Our results indicated that Gymnospermium is similar to other genera of Berberidaceae in terms of its embryological features. Nevertheless, newly reported and unique features are the well-developed endothelium and the undifferentiated seed coat type. Until the study of Gymnospermium, it may have been considered to be closer to Caulophyllum and Leontice in the tribe Leonticeae. These three genera share many morphological features as well as molecular similarities, by which they are kept in the same tribe, Leonticeae. However, very little detailed embryological data regarding these genera have been published thus far. Gymnospermium was characterized according to the basic type of anther wall formation as well as its glandular tapetum, successive cytokinesis in the microspore mother cell, two-celled mature pollen grains, anatropous and crassinucellate ovules with a nucellar cap, well-developed endothelium, its Polygonum type of embryo sac formation, its nuclear type of endosperm formation, and its undifferentiated seed coat type. In comparison with Nandina, there are many differences, such as the dehiscence of the anther, the cytokinesis in the microspore mother cells, the shape of the megaspore dyad, and the seed characteristics. Although we had no available detailed embryological information regarding Caulophyllum and Leontice, which are genera that are more closely related to Gymnospermium, we could deduce from the phylogenetic relationship that Gymnospermium, Caulophyllum, and Leontice are more closely related to each other than other genera of Berberidaceae on the basis of the seed characteristics.

• Research in Plant Disease
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• v.27 no.1
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• pp.8-16
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• 2021

This study was conducted to check the sterilization efficacy of microwave plasma (MWP) against the watermelon seeds infected with Acidovorax citrulli 11-251. Watermelon seeds were artificially vacuum inoculated to produce A. citrulli 11-251 infected seeds. Aac ImmunoStrip and scanning electron microscope (SEM) results suggests that, seeds (coat and endosperm) were infected under the concentration of 1×107/30 min. MWP sterlization process was carried out at 50 W (3 min, 5 min, and 10 min), 80 W (3 min, 5 min, and 10 min), and 100 W (3 min, 5 min, and 10 min). According to the results, MWP sterilized the artificially inoculated seed coats by 95.96% at 80 W/10 min and seed endosperms by 100% at 100 W/10 min respectively. Although, seeds were sterlized by MWP, germination rate of seeds were low as compared to non treated (negative control) seeds. Moreover, cell membrane of A. citrulli 11-251 was damaged while observed in SEM after sterilized with MWP. Further studies regarding the appropriate sterilization condition by MWP against A. citrulli infected seeds for germination will be conducted in our next study.