• The Journal of the Petrological Society of Korea
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• v.25 no.3
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• pp.261-281
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• 2016

Our knowledge of the lithosphere beneath the Korean Peninsula has been improved through petrologic and geochemical studies of upper mantle xenoliths hosted by Quaternary intraplate alkali basalts from Jeju Island. The xenoliths are mostly spinel lherzolites, accompanied by subordinate harzburgite and pyroxenites. The mantle xenoliths represent residual mantle material showing textural and geochemical evidence for at least a three-stage evolution, fractional partial melting, recrystallization, and metasomatism. Their composition primarily controlled by early fractional melt extraction and porphyroclastic and mylonitic fabrics formed in a shear-dominated environment, which was subsequently modified by residual slab-derived fluids (or melts). Modal metasomatic products occur as both anhydrous phase(orthopyroxene) and hydrous phase (phlogopite). Late-stage orthopyroxene is more common than phlogopite. However, chemical equilibrium is evident between the primary and secondary orthopyroxene, implying that the duration of post-metasomatic high temperatures enabled complete resetting/reequilibration of the mineral compositions. The metasomatic enrichment pre-dates the host Jeju Quaternary magmatism, and a genetic relationship with the host magmas is considered unlikely. Following enrichment in the peridotite protolith in the mantle wedge, the upper mantle beneath proto-Jeju Island was transformed from a subarc environment to an intraplate environment. The Jeju peridotites, representing old subarc fragments, were subsequently transported to the surface, incorporated into ascending Quaternary intraplate alkali basalt. The result of this study implies that long term material transfer in the transformation of geotectonic setting from a subarc to intraplate may have played a significant role in the evolution of lithospheric mantle, resulting in the enriched mantle domains, such as EM I or EM II in the lithospheric mantle beneath East Asia.

• Food Science and Preservation
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• v.11 no.1
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• pp.106-110
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• 2004

The objective of this study was carried out to investigate nutritional characteristics and biological activities effects of Korean leaf of Rosa davurica Pall. in vitro. They were extracted with methanol and then further fractionated to n-hexane, chloroform, ethyl-acetate, n-butanol and water from methanol extracts. Methods of the antigenotoxic used in this experiment were UVA/UVB absorption property and DPPH radical scavenge. The proximate compositions of leaves of Rosa dauvrica Pall were 67.5％ of crude Moisture, 0.7％ of crude fat, 6.8％ of crude protein, 6.1％ of crude ash, and 20.8％ of crude fiber. The major minerals were K (1637.2 mg％), Ca (219.5 mg％), P (182.1 mg％), and Mg (135.1 mg％). Most of the fractions of methanol extract which leaves of Rosa dauvrica Pall. have strong absorbency at UVB region (308 nm) and UV A region (350nm). These fractions have a good absorbency property as synthetic filter and could be served as substitutes for synthetic UV sunscreen agents. All fractions (n-hexane, ethyl-acetate, n-butanol and water) from methanol extracts except chloroform fraction exhibited DPPH radical scavenging activity with IC$\_$50/ of 35.3, 6.0, 14.0, and 18.0 $\mu\textrm{g}$/mL.

• Food Science and Preservation
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• v.6 no.4
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• pp.488-494
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• 1999

The changes in firmness, mineral compositions and pectic substances of Mume(Prunus mume Sieb. et Zucc) fruits during maturation were determined. An average weight of the fruits in 92days after full bloom was increased during maturation proceeded up to the range of 212∼232%, as compared with that of 64days. The rate of weight increase of 'Ohshuku' fruits was 257%, and it was highest among four varieties. The ratio of stone to flesh weight was decreased, but the diameter of the flesh of fruits was increased during maturation. The firmness of 'Koume' fruits was rapidly decreased from 78days after full bloom. Three varieties, except 'Koume' fruits, showed similar changes in firmness. Potassium content of fruits was 85%. Calcium and Mg were decreased as the flesh of fruits became plump. The ratios of hydrochloric acid-soluble pectin(HSP) , water-soluble pectin(WSP), sodium hexamethaphosphate-soluble pectin(PSP), and sodium hydroxode-soluble pectin(SSP) contents to the total pectin content of the fruits were 66∼76, 8.4∼19.7, 5.4∼7.5 and 7.1∼8.3%, respectively. The total pectin content was increased up to 71days after full bloom, but it was decreased thereafter. Also, a significant increase of WSP and a decrease of HSP were observed during the softening process of fruits.

• Food Science and Preservation
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• v.15 no.5
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• pp.719-724
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• 2008

The overall objectives of this study were to examine the potential of sturgeon as an intermediate moisture food (IMF) by measurement of nutritional components, such as minerals, fatty acids, amino acids, and water activity. Chemical compositions were as follows:moisture 73.2%, crude protein 19.9%, crude lipid 5.7%, ash 1.1%, and carbohydrate 0.1%. Minerals were K 317.70, P 259.88, and Mg 29.78 mg/100 g. Fatty acids detected were oleic acid (40.46% of total), palmitic acid (23.27%), and linoleic acid (15.35%). In addition, sturgeon was very rich in glutamic acid (1,189.71 mg/100 g) and deficient in serine (55.12 mg/100 g). Moisture content and water activity of sturgeon dried at $40^{\circ}C$ after soaking in different concentrationsof sugar and salt solutions were 15.12-16.24% and 0.68-0.79, respectively. Sensory evaluation of sturgeon soaked in different concentrations of sugar and salt solutions indicated that sturgeon soaked in 3.0% (w/v) sugar and salt solution scored highest.

• Food Science and Preservation
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• v.18 no.6
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• pp.961-966
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• 2011

This research was carried out to evaluate the value of tofu containing mushroom as a immunomodulator. Tofu was made using $CaSO_4{\cdot}2H_2O$ or Lactobacillus extract as a coagulant after adding powder of fruit bodies or mycelia of Letino edodes and Lepista nuda to soybean milk. Proximate compositions of tofu and tofu containing mushroom were analyzed. Levels of interferon ${\gamma}$ (IFN-${\gamma}$), interleukin 4 (IL-4) and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in culture media of lymphocytes collected from mouse spleens after being injected with mushroom, regular tofu, or tofu made with mushroom were measured by sandwich ELISA. In addition, concentrations of IgG1, IgG2a and IgE in plasma or lymphocyte culture media were analyzed. Crude protein, crude lipid and crude ash were decreased in tofu containing mushroom but phosphorus was increased significantly. IFN-${\gamma}$ concentration was significantly decreased in mice injected with fruit body or tofu alone. IL-4 level was decreased significantly in mice injected with tofu containing fruit body of L. edodes. However, TNF-${\alpha}$ was increased in mice injected with tofu containing fruit body of L. edodes. Plasma levels of IgG1 were increased in almost all groups, while there was no significant change in IgG2a levels among treated mice groups. Concentrations of IgG1 and IgG2a were increased significantly in lymphocyte culture media of mice injected with tofu containing mushroom. Plasma levels of IgE level was significantly increased in mice injected with tofu or fruit body of L. edodes, but not in mice treated with tofu containing mushroom. These results showed that tofu with mushroom affected immune activities, and it seems valuable to consider developing the mixture of tofu and L. edodes as an immunomodulator.

• Food Science and Preservation
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• v.19 no.4
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• pp.569-576
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• 2012

This study was conducted to compare the major chemical components of Korea Crataegi fructrus (KCF) and Chinese Crataegi fructrus (CCF). Among the proximate compositions, the curde fat content of KCF was lower than that of CCF, whereas their crude protein, crude ash and carbohydrate contents were similar. CCF had a higher total free sugar content than KCF. The major free sugars of KCF and CCF were identified as fructose and glucose. The value of glutamic acid was greater in the amino acids of KCF and CCF, and KCF had higher total amino acids and essential amino acids contents than CCF. KCF also had a higher level unsaturated fatty acids than CCF. CCF had a higher organic acid content, but both KCF and CCF had high citric acid levels. and Chinese The vitamin C contents of KCF and CCF were 272.69 mg per 100 g and 262.38 mg per100 g, respectively. The mineral content of KCF was higher than that of CCF, in the following order : K > Ca > Mg > Fe. The results showed that KCF had higher total amino acid, essential amino acid, unsaturated fatty acid and mineral contents and CCF had higher free sugar and organic acid contents.

• Korean Journal of Plant Resources
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• v.27 no.2
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• pp.119-124
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• 2014

This study was accomplished to investigate the effect of harvest time on the contents of polyphenolic compounds such as epicatechin, catechin, resveratrol and quercetin in grapes (Vitis spp.). The souble solids contents were increased with harvest time delay, while the titratable acidity continuously decreased in all cultivars. Brightness (L) was higher in 'Campbell Early' and 'Shigyoku', Hunter a value was high in 'Shigyoku' which was harvested later. Hunter b value seemed to be different in 'Shigyoku' depending on harvesting time. The contents of EC which was extracted 'Campbell Early, 'Shigyoku' and 'M.B.A' were higher late harvest time than early harvest time, reapectively, In 'Shigyoku which requires the direct light, the contents of EGC and EC showed distinct differences depending on harvesting time. The compositions of epicatechin were different depending on cultivars. The contents of catechin and resveratrol were higher in 'Campbell Early' and 'M.B.A' which were harvested later, but 'Shigyoku' which was harvested earlier. The contents of quercetin was higher in 'Campbell Early' which was harvested earlier, but 'Shigyoku' and 'M.B.A' which were harvested later. In comparison with 'Shigyoku' and 'M.B.A', catechin and resveratrol contents were seen to be higher in 'Campbell Early' irrespective of harvesting time.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.739-748
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• 2021

This study focuses on the use of rice in the production of gluten-free rice udon (GFU) through an optimized mixing ratio, using the Box-Behnken response surface methodology (RSM). Different additional levels of rice flour (A, 40-60 g), acetylated distarch adipate (B, 10-20 g), and trehalose (C, 0-3 g) were used as variables, while water absorption level, volume, cooking loss, solid yield, lightness, texture properties, proximate compositions of GFU and turbidity of cooking water were set as responses in the RSM design model. The optimum mixing ratio for the preparation of gluten-free rice udon was obtained for 60.00 g of rice flour, 18.81 g of acetylated distarch adipate without the addition of trehalose. The response values of the optimized samples were water absorption (60.94%), volume (34.94%), turbidity of the cooking water (0.37), cooking loss (4.77%), solid yield (1.55 g), lightness value (70.04), hardness (2.53 N), springiness (0.18), gumminess (10.45 N), chewiness (1.83 N), and cohesiveness (2.89). This study has shown that rice flour can replace wheat flour to manufacture udon at an optimized mixing ratio successfully derived by statistical estimation method.

• Microbiology and Biotechnology Letters
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• v.49 no.3
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• pp.458-465
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• 2021

Tubulysins are a group of bioactive secondary metabolites from myxobacteria exhibiting strong anticancer activity against various cancer cell lines. In this study, we describe the identification of putative tubulysin biosynthetic gene clusters (tubA~tubF) in the genome sequences of two tubulysin-producing myxobacterial strains, Archangium gephyra MEHO_002 and MEHO_004. The inactivation of the putative tubulysin biosynthetic genes resulted in a tubulysin-production defect. The DNA sequences of the A. gephyra MEHO_002 and MEHO_004 tubulysin biosynthetic genes were 97% identical, and the amino acid sequences of the encoded proteins shared a similarity of 97-100%. The nucleotide sequences of the tubulysin biosynthetic gene clusters in MEHO_002 and MEHO_004 were 86% identical to that in Cystobacter sp. SBCb004 known as a tubulysin-producing myxobacterium, and the organization of the clusters was identical except for the lack of a tubZ gene in the clusters in MEHO_002 and MEHO_004. The amino acid sequences of the proteins encoded by each gene were 88-97% similar to those encoded by SBCb004, and the domain compositions of the proteins were also identical.

• Journal of Plant Biotechnology
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• v.47 no.4
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• pp.261-272
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• 2020

Approvals for cultivation and import of genetically modified (GM) crops have dramatically increased around the world. Comparative compositional studies are an important aspect of safety assessments of products from GM crops and are based on substantial equivalence. Compositional analyses focus on determining similarities and differences between the compositions of the GM crops and their conventional counterparts, and thereby assessing the compositional equivalence of GM crops and their conventional comparators. The analytes, such as major constituents, key nutrients, and antinutrients, are generally determined on a crop-specific basis according to the OECD consensus document. The use of standard methods throughout the processes, such as selection of comparators, field trials, analytical methods, and statistical data analysis, is crucial. In this study, we showed the general framework of compositional studies. Literature for compositional studies of GM crops conducted abroad and in Korea was reviewed to obtain information about analytes, conventional counterparts, cultivation year, location, and statistical methods. The studies conducted abroad assessed for commercial release of GM crops such as soybean, maize, and cotton, while domestic studies were mainly performed for research in rice. In addition, we suggested a guidance for conventional comparators and field trials applicable to the domestic situation.