• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.4
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• pp.263-268
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• 2013

We investigated the range of linoleic acid concentrations in different forage species and harvest stages. The linoleic acid concentrations in main cultivated grasses and forage crops were analyzed at three harvesting dates in Korea. The experiment compared 19 species of main grasses and forage crops, including eight species of grasses (Perennial ryegrass, Reed canarygrass, Tall fescue, Timothy, Bromegrass, Kentucky bluegrass, Orchardgrass and Wheat grass), six legumes (White clover, Red clover, Sweet clover, Crimson clover, Alfalfa and Hairy vetch) and five forage crops (Italian ryegrass, Barley, Rye, Oat and Rape) in Korea with three cuts (8 May, 19 May and 28 May). The linoleic acid concentrations of Reed canarygrass and Timothy were the highest, and Bromegrass was the lowest among the grass species. All grass species had high concentrations of linoleic acid at the late May harvest stage but were low at the mid May harvest stage. Legumes had higher linoleic acid concentrations than those of grasses, and harvesting in mid-May resulted in the highest linoleic acid concentration. Rape had the highest linoleic acid concentration and rye showed high concentrations of linoleic acid when compared with those of forage crops. All species of grasses and forage had decreased linoleic acid concentrations by the harvest stage. We have demonstrated opportunities to change the composition of ruminant products through breeding, selection, and management of grasses for altered levels of linoleic acid as a precursor to conjugated linoleic acid.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.529-532
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• 2002

The angiotensin converting enzyme (ACE) inhibitory activity in peptic hydrolysate of raw anchovy cooking discards was 51.3% at 1 mg of protein per $100\;{\mu}L$ sample solution. While, after the treatment of pepsin for 4 h, was 65.8%. The crude peptides fractionated through Bio-gel P-2 column chromatography consisted of five fractions $({P-1}{\sim}{P-5})$ and had maximum inhibitory activity in the fraction P-2 ($IC_{50}$=0.319 mg protein/mL). The fraction P-2 was rich in aspartic acid, glutamic acid, and glycine.

• Resources Recycling
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• v.29 no.1
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• pp.17-24
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• 2020

In this study, rare earth elements (REE) leaching from a refractory REE ore containing goethite as a major gangue mineral was conducted, introducing a two-stage method of chemical decomposition-acid leaching. At the chemical decomposition step, using one of alkaline agent, NaOH, the ore was decomposed, changing NaOH concentration from 20 to 50 wt% at 10% (w/w) of pulp density and the maximum temperature achieved without boiling at each NaOH concentration. With increasing NaOH concentration, light REE (Ce, La and Nd) and iron were concentrated in the solid phase which is the decomposed product, while aluminum (Al) and phosphorus (P) were removed to the liquid phase, and their concentrations in the solid phase were down to 0.96 and 0.17%, respectively. In addition, through XRD analysis, it was found that the crystallinity of goethite was considerably decreased. At the acid leaching step, the product decomposed by 50 wt% NaOH was leached at 3.0 M HCl and 80 ℃ for 3 hr, then the REE leaching efficiency was above 94% (Ce 80%), and the leaching efficiencies of Al and P were decreased to 12 and 0%, respectively. Therefore, in terms of both REE leaching efficiency and impurity removal, those decomposition and leaching conditions were chosen as optimum processing methods of the investigated material. In terms of REE leaching mechanism, because REE and iron leaching efficiencies showed the positive correlation each other, so it can be concluded that decreasing crystallinity of goethite affect the improvement of REE leaching.

• Anatomy & Biological Anthropology
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• v.27 no.3
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• pp.155-163
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• 2014

This study aimed to investigate the cusp size and morphological characteristics of permanent mandibular molars in Koreans with reference to the hypoconulid, and to analyze the differences and correlations between both sexes as well as between first and second mandibular molars. We obtained data from dental casts of 110 adults (78 males and 32 females). Mesiodistal and buccolingual diameters of first and second mandibular molars, the area of five cusps (protoconid, metaconid, hypoconid, entoconid, and hypoconulid), as well as the total cusp area and occlusal table area were measured. Paired t-test was performed to analyze the morphological differences between first and second mandibular molars and the sex differences between both sexes using SPSS program. Crown diameters and cusp areas of mandibular first molars were larger than those of mandibular second molars in both sexes. The hypoconulid was the most variable in size and morphological pattern among the five cusps, and the first molars showed a higher incidence of hypoconulid than the second molars. Except for the entoconid area of the first molar (p=0.06) and the hypoconulid area of the second molar (p=0.24), all other mean values were larger in males than in females, demonstrating a significant sexual dimorphism. These data suggest that the teeth which develop late in ontogeny tend to be smaller in size and more variable in morphological characteristics.

• Journal of agriculture & life science
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• v.44 no.2
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• pp.57-66
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• 2010

The antioxidant and neuronal cell protective effects of water extract from purple sweet potato were investigated. The total phenolics and monomeric anthocyanin contents of purple sweet potato extract were 44.25 mg/g and 2,394 mg/L, respectively. The antioxidant activities of purple sweet potato extract were evaluated using various antioxidant tests, including 1,1-diphenyl- 2-picrylhydrazyl (DPPH), 2,2'-azino- bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activities, ferric reducing/antioxidant power (FRAP) and reducing power. In these assays, the extract of purple sweet potato presented significant radical scavenging activities, FRAP, and reducing power in a dose-dependent manner. MTT {3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl- tetrazoliumbromide} reduction assay showed significantly increase in cell viability when PC12 cells were pretreated with purple sweet potato extract. Because oxidative stress is also known to increase neuronal cell membrane breakdown, we further investigated by lactate dehydrogenase (LDH) and neutral red uptake assay. Purple sweet potato extract inhibited oxidative stress-induced membrane damage in neuronal cells. Therefore, these data results demonstrated that water extract of purple sweet potato have antioxidant activity and neuronal cell protective effect thus it has great potential as a natural source for human health.

• Journal of agriculture & life science
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• v.45 no.6
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• pp.183-191
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• 2011

We investigated characterization as cosmetic substances of chestnut inner skin extracts with in vitro antioxidant activity. Total phenolics of various extracts from chestnut inner skin were the highest 60% methanol (164.82 mg/g), and ethyl acetate fractions (191.14 mg/g). We found that the both samples from chestnut inner skin dose-dependently increased in vitro antioxidant activities (DPPH radical scavenging activity and inhibition of lipid peroxidation). In addition, the both samples also showed a strong UV absorption in the range of UV-B (290-320 nm). Especially the 60% ethanol extracts presented higher inhibitory effect on elastase (46.40% at $100{\mu}g/mL$) than that of the ethyl acetate fractions, so that it showed in vitro anti-wrinkle activity. Finally, the 60% methanol extracts and ethyl acetate fractions showed anti-bacterial activity against skin pathogenic bacteria. Consequently, these results suggest that the chestnut inner skin can be used for cosmetic industry.

• Korean Journal of Social Welfare Studies
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• v.49 no.4
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• pp.159-193
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• 2018

This study aims to examine life experiences of single mothers according to three types of single parent families, divorced, widowed and unmarried and how they cope with their difficulties to become self-reliant and to identify strengths promoting self-reliance. The researchers analyzed personal, environmental and life factors by using the strengths perspective and discovered distinctive features of three types of single mothers that promote self-reliance. Data were collected by in-depth interviews with 20 single mothers, 4 widows, 8 divorced mothers and 8 unmarried single mothers. The results show that participants defined their experiences of self-reliance as a process to increase capability to accomplish their responsibilities as a mother, rather than as a completed goal. Increasing capability not only means achieving economic self-sufficiency, but also gaining psychosocial strengths that are developed by embracing one's own life, having sense of control and empowerment. This study identified commonalities and differences of strengths and resources and unique experiences of participants and proposed implications for policy and practice related to the roles of service delivery and support system.

• Korean Journal of Plant Taxonomy
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• v.32 no.3
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• pp.257-292
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• 2002

Morphological characters of sections Foetidae(one taxon), Arenariae(one taxon) and Multiflorae(six taxa) of genus Carex(Cyperaceae) were reexamined. The epidermal patterns of perigynium, achene and leaf were investigated using by a scanning electron microscope(SEM) and a light microscope(LM). Morphological characters, such as length and width of stem, leaf, leaf sheath, bract, spike, scale, perigynium and beak of perigynium, length of spike peduncle, size and frequency of stomatal complex of leaf, number of bract, shape of stem transection, scale and apex of scale, beak and base of perigynuim, achene, epidermal cell and cell wall of perigynium, achene, leaf epidermal patterns(fundamental epidermal cell and cell wall, silica body, subsidiary cell), hair, papillae present/absent of perigynium, and leaf were useful for the identification of observed eight taxa. According to the current study, examined eight taxa of sections Foetidae, Arenariae and Multiflorae were distinct from each other with respect to length and width of stem, leaf, bract, perigynium, perigynium beak, length of spike peduncle, shape of bract, scale and apex of scale, perigynium, perigynium beak, hair presence/absence of perigynium and leaf. A key based on data was presented here.

• YAKHAK HOEJI
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• v.58 no.5
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• pp.307-313
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• 2014

Rumex crispus (curled dock), which is a perennial wild plant, has long been used as a laxative, astringent, and medicine to treat blood and skin diseases. We recently reported that the roots of R. crispus are an effective nutraceutical for bone. This study prepared ethanol extracts of the leaves and roots of R. crispus, and analyzed the major constituents using liquid chromatography and mass spectrometry. In addition, their effects on the proliferation and differentiation of human osteoblast-like MG-63 cells, such as cell viability, alkaline phosphatase (ALP) activity, collagen content, and mineralization, were compared. The chromatograms of the chemical constituents of the two extracts exhibited quite different profiles: quercetin and quercitrin were identified as major peaks in the leaf extract, whereas cinnamtannin B1 and procyanidin isomers were the major peaks for the root extract. Neither extract was cytotoxic at concentrations of < $25{\mu}g/ml$. ALP activity and collagen synthesis-which are markers of the early stage of osteogenesis-in MG-63 cells were significantly increased upon the addition of the root extract compared with the addition of the leaf extract. In contrast, the leaf extract had a more stimulatory effect on mineralization-which is marker of the late stage of osteogenesis-in MG-63 cells than did the root extract. In conclusion, extracts of both leaves and roots of R. crispus stimulated the bone-forming activity of osteoblasts; in particular, the root extract was more effective in the early stage of osteoblast differentiation, while the leaf extract was more effective in the late stage. This difference in anabolic activity may be due to differences in the constituents of the leaves and roots. The leaves and roots of R. crispus appear to complement each other as stimulators of bone formation.

• Food Science and Preservation
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• v.17 no.5
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• pp.720-726
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• 2010

The in vitro antioxidant activities and neuronal cell protective effects of 60% (w/v) methanolic extract from Houttuynia cordata were investigated. The contents of total phenolics and quercitrin in the extract were 17.71 mg/g and 75.80 ${\mu}g$/g, respectively. DPPH and ABTS radical-scavenging activities were 87.79% and 99.27%, respectively, when the extract was tested at 5 mg/ml. The FRAP (ferric reducing/antioxidant power) assay showed a dose-dependent increse in activity. In a cell viability assay using MTT, the extract protected against $H_2O_2$-induced neurotoxicity. Lactate dehydrogenase (LDH) leakage was also inhibited by the extract, as was lipid peroxidation as shown using the mouse brain homogenate test. These data indicate that a 60% (w/v) methanolic extract of Houttuynia cordata has in vitro antioxidant activities, and ingestion there of may reduce the risk of developing neurodegenerative disorders.