• Kyungpook Mathematical Journal
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• v.60 no.1
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• pp.53-69
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• 2020

Let (A, M) ⊂ (B, N) be commutative quasi-local rings. We consider the property that there exists a ring D such that A ⊆ D ⊂ B and the extension D ⊂ B is inert. Examples show that the number of such D may be any non-negative integer or infinite. The existence of such D does not imply M ⊆ N. Suppose henceforth that M ⊆ N. If the field extension A/M ⊆ B/N is algebraic, the existence of such D does not imply that B is integral over A (except when B has Krull dimension 0). If A/M ⊆ B/N is a minimal field extension, there exists a unique such D, necessarily given by D = A + N (but it need not be the case that N = MB). The converse fails, even if M = N and B/M is a finite field.

• The Korean Journal of Food And Nutrition
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• v.30 no.4
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• pp.710-718
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• 2017

Contents of water soluble vitamin $B_6$ in a total of 62 agricultural products cultivated in local areas in Korea were analyzed by high performance liquid chromatography with fluorescence detector (HPLC/FLD). To verify the method of vitamin $B_6$ analysis, a quality control chart was formulated with in-house control using a mixture of broccoli and shiitake mushrooms. Among cereals, high content of vitamin $B_6$ measured $234.3{\sim}260.3{\mu}g/100g$ in dried mung bean and soybean. Vitamin $B_6$ content of non-glutinous and glutinous black rice measured $105.0{\mu}g/100g$ and $129.7{\mu}g/100g$, respectively. In vegetables, high content of vitamin $B_6$ were measured in passion fruit ($104.3{\mu}g/100g$), gat ($55.7{\sim}84.3{\mu}g/100g$), gomchwi ($31.3{\sim}88.0{\mu}g/100g$) and garlic ($72.7{\sim}98.3{\mu}g/100g$). Among fruits, gold kiwi 'Zespri' and green kiwi 'Hayward' revealed high vitamin $B_6$ content of $116.3{\mu}g/100g$ and $78.7{\mu}g/100g$, respectively. In persimmons, daebongsi had high vitamin $B_6$ content ($36.0{\sim}72.7{\mu}g/100g$) than bansi and sweet persimmon. Vitamin $B_6$ content in dried jujube and persimmon increased more than $86.7{\mu}g/100g$ compared to fresh materials. Among specialty crops, green tea powder ($64.7{\sim}251.0{\mu}g/100g$) and sansuyu ($172.3{\mu}g/100g$) revealed high content. Of mushrooms, vitamin $B_6$ content of Sparassis crispa ($139.3{\mu}g/100g$) was the highest. Vitamin $B_6$ content information of agricultural products in local areas in Korea collected from this experiment will be used as valuable preliminary data for grasp national nutritional status.

• Korean Journal of Breeding Science
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• v.43 no.3
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• pp.218-221
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• 2011

A mungbean cultivar 'Juhyeon' (Vigna radiata (L.) Wilczek) was derived from the cross between Keumseong and VC1834-4-B-2-B-3B-B at Jeollanamdo Agricultural Research & Extension Services (JARES) in 2009. 'Juhyeon' has an erect growth habit, heart leaflet, green hypocotyl, black and straight pod when matured, and dull green seed surface. The pod number per plant was 26, which was 8 more than check cultivar 'Owool'. The plant height and thousand seed weight were 66 cm and 47 g, respectively. This cultivar has field resistance to mungbean mottle virus, cercospora leaf spot, powdery mildew, and lodging. The sprout yield was up to 18% more than that of the check cultivar. The average yield was 1.84 MT/ha, which was 6% more than the check cultivar.

• The Plant Pathology Journal
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• v.17 no.6
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• pp.390.3-390
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• 2001

• Communications of the Korean Mathematical Society
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• v.25 no.3
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• pp.349-364
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• 2010

P. M. Cohn called a ring R reversible if whenever ab = 0, then ba = 0 for a, $b\;{\in}\;R$. Commutative rings and reduced rings are reversible. In this paper, we extend the reversible condition of a ring as follows: Let R be a ring and $\alpha$ an endomorphism of R, we say that R is right (resp., left) $\alpha$-shifting if whenever $a{\alpha}(b)\;=\;0$ (resp., $\alpha{a)b\;=\;0$) for a, $b\;{\in}\;R$, $b{\alpha}{a)\;=\;0$ (resp., $\alpha(b)a\;=\;0$); and the ring R is called $\alpha$-shifting if it is both left and right $\alpha$-shifting. We investigate characterizations of $\alpha$-shifting rings and their related properties, including the trivial extension, Jordan extension and Dorroh extension. In particular, it is shown that for an automorphism $\alpha$ of a ring R, R is right (resp., left) $\alpha$-shifting if and only if Q(R) is right (resp., left) $\bar{\alpha}$-shifting, whenever there exists the classical right quotient ring Q(R) of R.

• The Korean Journal of Food And Nutrition
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• v.26 no.2
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• pp.266-272
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• 2013

This study investigated the quality characteristics of black soybean paste(Daemacjang) with black soybean content and salt concentration. The total acidity increased as the pH decreased during fermentation period. The amino-type nitrogen content of all samples increased significantly during fermentation time. Total cell counts was not significantly different during fermentation, and mold counts decreased at 3 log cycles. The cell counts of lactic acid bacteria decreased approximately 2 to 3 log cycles in 10% salt concentration (treat B and C), and were not detected in treat A and D. Total polyphenol contents of treat A, B, and C were 42.77%, 52.99% and 52.95% during fermentation up to 70days, respectively, which was higher than D (39.86%). In a sensory evaluation, treat B showed the highest scores for overall acceptability.

• Food Science and Preservation
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• v.30 no.1
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• pp.98-108
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• 2023

The purpose of this study was to determine the vitamin B₁ and B₃ contents in 135 Korean domestic foods using high performance liquid chromatography (HPLC). The Standard Reference Material (SRM) 3233 and in-house control (grain, whole wheat and flour mixture) were used for quality control/assurance. As a result, vitamin B₁ was only detected in 54 of the 135 foods, ranging from 0.019 mg/100 g to 28.218 mg/100 g. Among the foods tested, the vitamin B₁ content was highest in ramen powder (28.218 mg/100 g) and lowest in boiled jjolmyeon (0.019 mg/100 g). In contrast, vitamin B₃ was detected in 108 of the 135 foods, ranging from 0.077 mg/100 g to 32.412 mg/100 g. We found that the vitamin B₃ content was highest in beef liver (32.412 mg/100 g) and lowest in boiled chicken heart (0.077 mg/100 g). The results of this study will be used as a nutritional database for the update of the Korean food composition table and will hence contribute to improving public health.

• Journal of the Korean Applied Science and Technology
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• v.36 no.4
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• pp.1119-1127
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• 2019

This study analyzes the content of niacin, B1, and B2, which are among the water-soluble vitamin B group, in cultivars of the commonly consumed agricultural products of apples, peaches, nectarines and strawberries to compare content differences and to use results as base material for the Korean Food Composition Table. While the vitamin B1 content of apples according to different cultivars was found to be within the ranges of 0.063-0.208 mg/100g, and the content of vitamin B2 was found to be within the value ranges of 0.006-0.031 mg/100g, no niacin was found. The vitamin B1 content of peaches and nectarines according to different cultivars was found to be within the value ranges of 0.014-0.276 mg/100g, the content of vitamin B2 was found to be within he value ranges of 0.019-0.042 mg/100g, and niacin content was found to be within the value ranges of 0.298-1.096 mg/100g. The vitamin B1 content of strawberries according to cultivars was found to be within the value ranges of 0.112-0.394 mg/100g, the content of vitamin B2 was found to within the value ranges of 0.001-0.027 mg/100g, and niacin content was found to be within the value ranges of 0.388-0.809 mg/100g. Therefore, when nutrient composition analysis databases for the fruits of apples, peaches, and strawberries are constructed, cultivar factors must be put into consideration. In addition, differences can be found according to fruit harvest times, cultivation methods, and environmental factors, so related additional is needed.

• The Korean Journal of Food And Nutrition
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• v.32 no.6
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• pp.745-752
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• 2019

The purpose of this study was to determine the difference in vitamin B₆ content according to the varieties, regions, and harvest times of vegetables and fruits in Korea using high performance liquid chromatography. We verified the accuracy of the analytical method with standard reference material 1849a and achieved reliability for internal analysis quality control with a mixture of cereal, whole wheat, and flour. As a result of the analysis, vitamin B₆ contents (㎍/100 g) were 6.9~86.5 in peppers, 5.1~17.2 in paprika, 4.4~5.0 in strawberries, 4.0~52.9 in tomatoes, 7.7~7.8 in Chinese cabbage, 17.3~23.3 in radishes, 13.4~37.6 in apples, 2.3~12.7 in peaches, and 3.7~12.7 in grapes. In general, the difference in vitamin B₆ content showed by varieties, harvest times, and regions. Peppers showed the most difference as 79.6 ㎍/100 g among the varieties, and apples showed a difference as 22.8 ㎍/100 g by regions. According to the harvest times in grape 'Mihwang', there was a difference of 7.5 ㎍/100 g. We will collect an amount of nutritional data on various food materials, and continue to build a reliable and integrated nutritional database. And then the database will be used in the 10th revision of the Korean Food Composition Table.

• 한국균학회소식:학술대회논문집
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• 2015.11a
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• pp.35-35
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• 2015

Pleurotus eryngii has recently become a major cultivated mushroom; it uses tetrapolar heterothallism as a part of its reproductive process. Sexual development progresses only when the A and B mating types are compatible. Such mating incompatibility occasionally limits the efficiency of breeding programs in which crossing within loci-shared strains or backcrossing strategies are employed. Therefore, understanding the mating system in edible mushroom fungi will help provide a short cut in the development of new strains. We isolated and identified pheromone and receptor genes in the B3 locus of P. eryngii and performed a functional analysis of the genes in the mating process by transformation. A genomic DNA library was constructed to map the entire mating-type locus. The B3 locus was found to contain four pheromone precursor genes and four receptor genes. Remarkably, receptor PESTE3.3.1 has just 34 amino acid residues in its C-terminal cytoplasmic region; therefore, it seems likely to be a receptor-like gene. Real-time quantitative RT-PCR (real-time qRT-PCR) revealed that most pheromone and receptor genes showed significantly higher expression in monokaryotic cells than dikaryotic cells. The pheromone genes PEphb3.1 and PEphb3.3 and the receptor gene PESTE3.3.1 were transformed into P5 (A3B4). The transformants were mated with a tester strain (A4B4), and the progeny showed clamp connections and a normal fruiting body, which indicates the proposed role of these genes in mating and fruiting processes. This result also confirms that PESTE3.3.1 is a receptor gene. In this study, we identified pheromone and receptor genes in the B3 locus of P. eryngii and found that some of those genes appear to play a role in the mating and fruiting processes. These results might help elucidate the mechanism of fruiting differentiation and improve breeding efficiency.