• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.64.2-64.2
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• 2016

지난 2015년 4월, 젊은 천문학자 모임(Young Astronomers Meeting, YAM)은 봄 정기총회를 가졌고 2015-16 시즌을 위한 임원진으로 회장 현민희, 부회장 안성호, 총무 박진태가 선출되었다. 이 외에도 각 학교별 운영위원으로 경북대학교 신지혜, 경희대학교 윤형식, 서울대학교 정하은, 세종대학교 허정은, 연세대학교 홍승수, 충남대학교 유현주, 과학기술연합대학원대학교 이혜란 회원이 활동 중이다. 현 임원진은 이번 임기 내 목표로 지금까지의 YAM 역사를 정리하고, 이를 공유할 수 있는 홈페이지를 구축하고자 하였다. YAM 역사 정리 부분에서는, 1991년 서울대학교에서 개최된 한국천문학회에서의 YAM 창단 이후의 모든 활동과 역대 임원진에 대한 서류 자료를 정리하고 홈페이지에 게시하였다. YAM 홈페이지 구축 부분에서는 지난 2015년 8월, 한국천문학회에 YAM 홈페이지 구축을 위한 제안서를 제출, 2016년 초에 학회의 승인을 받아 한국천문학회 홈페이지 서버에 YAM 홈페이지를 개설하였다. 이와 더불어 2016년 2월에 개최된 "2016 YAM & We Love Galaxies 공동 워크샵"을 통해 국내 대학원생들을 위한 워크샵을 개최하고 추후 지속적으로 진행할 수 있도록 노력하였다. 이번 포스터 발표를 통해 2015-16 시즌 동안의 활동 결과 보고와 2016-17 시즌 활동 계획을 논의할 것이다.

• Food Science and Preservation
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• v.21 no.5
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• pp.636-645
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• 2014

Quality changes in frankfurter sausages with yam (Dioscorea japonica) powder added were investigated during their storage at $10^{\circ}C$ for six weeks. The sausage samples were prepared using four concentrations of yam powder: 0% (C), 0.5% (T1), 1.0% (T2), and 2.0% (w/w) (T3). After the addition of yam powder, the crude protein contents decreased, but the crude fat and carbohydrate contents increased. The thiobarbituric acid values during the storage of the frankfurter sausages were lower in the samples with higher yam concentrations. Over the storage period, the volatile basic nitrogen values increased with the increase in the amount of added yam. With the increase in the yam concentration, the $L^*$ and $a^*$ values tended to decrease, whereas the $b^*$ value increased. The instrumental texture analysis showed that the hardness value decreased with the increase in the yam concentration. The first indication of sensorial quality deterioration was noticed at week 4 for T3 and at week 5 for C, T1, and T2. In conclusion, the quality and shelf-life of the frankfurter sausages were not noticeably influenced by the addition of yam powder with a concentration of up to 1.0% (w/w), but the functional and health-promoting effects of yam were positively incorporated.

• Korean journal of food and cookery science
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• v.8 no.1
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• pp.57-63
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• 1992

The purpose of this study was to investigate the rheological and thermal properties of yam starch. Yam starch had a hydrodynamic volume with the intrinsic viscosity,［$\eta$］, of 0.29dl/g deionized water. The values of the intrinsic viscosity of yam starch, determined to pH 2-11, varied between 0.07 to 0.18 dl/g. The highest intrinsic viscosity was obtained at pH 7. At salt concentrations 0-0.2 M NaCl, the intrinsic viscosity of yam starch was decreased up to 0.05 M NaCl concentration then increased to 0.07 M NaCl concentration and remained constant to reach 0.2 M NaCl concentration. The overlap parameter, calculated with the intrinsic vicosity data, was 3.45 g/dl in deionized water. The thermal properties of yam starch were investigated by Differential Scanning Calorimetry. Three endotherms were observed both pH solution and salt concentation. In the presence of pH 9, the onset temperature of gelatinization peak was the lowest temperature of 50.$32^{\circ}C$ and the enthalpy ($\Delta$H) was increased in this solution. The effect of salt on the thermal properties of yam starch was determined at salt concetration of 0-0.2 M NaCl. The enthalpy significantly decreased to salt concentration 0.07 M NaCl and the lowest onset temperature of this concentration was 52.$90^{\circ}C$.

• Preventive Nutrition and Food Science
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• v.19 no.2
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• pp.82-88
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• 2014

Yam (Dioscorea batatas Decne.) has long been used as a health food and oriental folk medicine because of its nutritional fortification, tonic, anti-diarrheal, anti-inflammatory, antitussive, and expectorant effects. Reactive oxygen species (ROS), which are known to be implicated in a range of diseases, may be important progenitors of carcinogenesis. The aim of this study was to investigate the modulatory effect of yam on antioxidant status and inflammatory conditions during azoxymethane (AOM)-induced colon carcinogenesis in male F344 rats. We measured the formation of aberrant crypt foci (ACF), hemolysate antioxidant enzyme activities, colonic mucosal antioxidant enzyme gene expression, and colonic mucosal inflammatory mediator gene expression. The feeding of yam prior to carcinogenesis significantly inhibited AOM-induced colonic ACF formation. In yam-administered rats, erythrocyte levels of glutathione, glutathione peroxidase (GPx), and catalase were increased and colonic mucosal gene expression of Cu/Zn-superoxide dismutase (SOD), Mn-SOD, and GPx were up-regulated compared to the AOM group. Colonic mucosal gene expression of inflammatory mediators (i.e., nuclear factor kappaB, inducible nitric oxide synthase, cyclooxygenase-2, tumor necrosis factor alpha, and interleukin-1beta) was suppressed by the yam-supplemented diet. These results suggest that yam could be very useful for the prevention of colon cancer, as they enhance the antioxidant defense system and modulate inflammatory mediators.

• Journal of Food Hygiene and Safety
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• v.36 no.4
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• pp.347-352
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• 2021

Yam (Dioscorea japonica) is widely utilized as food and a pharmaceutical ingredient as it contains a variety of valuable constituents. Allantoin is one of the bioactive components in yam that is used in pharmaceutical and cosmetic industry. This study was conducted to analyze and compare the allantoin content of yam flesh and peel by HPLC analytical method using an amino bonded-phase column to make up for the limitations of the previous HPLC analytical methods. The allantoin contents of yam flesh and peel were 3.09±0.025 and 3.91±0.11 mg/g (dry weight), respectively. The results of this study indicated that yam peel has higher allantoin content than yam flesh, and that the discarded yam peel could be used as a source for high value-added functional materials.

• Microbiology and Biotechnology Letters
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• v.35 no.1
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• pp.66-72
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• 2007

Yam has been recognized as healthy food due to its various biological activities, such as anti-obesity, antimicrobial, anticancer and immune-stimulation activities. In this study, antibacterial activities of 800 more natural plant extracts against yam-putrefactive psychrotrophic bacterium, Pseudomonas rhodesiae YAM-12, were evaluated to select a natural preservative, which is useful to long-term storage of yam and fresh-cut production. Finally, the clove oil was selected, and applied for the production of yam fresh-cut. The 1% of clove oil treated fresh-cut showed minor color changes during 31 days storage at $4^{\circ}C$ and the microbial growth was not detected. When the artificially contaminated fresh cut by dipping with P. rhodesiae YAM-12 suspension for 3 min was treated 1% clove oil, the microbial growth was identified to $10^4$ CFU/g from $10^3$ CFU/g with minor color changes. Whereas, treatment of sterilized water, or 100 ppm NaOCl into artificially contaminated fresh cut showed severe putrefaction $(10^8\;CFU/g)$ and color changes. Considering the previous reports that clove oil has antimicrobial, antioxidation, and antithrombosis activity, the use of clove oil into the yam fresh cut will provide market safety and consumer acceptability by prevention of microbial putrefaction and its biological activity.

• Journal of Life Science
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• v.34 no.3
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• pp.153-159
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• 2024

Dioscorea alata L, commonly known as "tropical yam" is the most widely consumed yam species among the 650 yam species belonging to the Dioscoreacea family. It is extensively cultivated in tropical and subtropical regions and is a major food source in Africa and India. Also, it is used for medicinal purposes, particularly in China and Taiwan, for its anti-inflammatory properties. In comparison to other yam varieties such as D. batatas or D. opposita, the tropical yam has gained popularity in Korea due to its higher yield per unit area. In this study, the nutritional characteristics and anti-thrombosis activity of the aerial bulbils of D. alata L. tropical yam were compared to those of D. opposita. The results showed that the aerial bulbils of tropical yam exhibited nutritional characteristics and potent anticoagulant activity compared to those of domestic yam varieties. The bulbils extract of tropical yam showed superior anticoagulant activities against thrombin, prothrombin and blood coagulation factors. Furthermore, the bulbils extract of tropical yam exhibited strong platelet aggregation inhibition at 0.25 mg/ml and showed no hemolytic activity up to a concentration of 2.5 mg/ml. These findings suggest the potential development of high-value anti-thrombosis agents utilizing the aerial bulbils of tropical yam.

• Nutrition Research and Practice
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• v.1 no.2
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• pp.94-99
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• 2007

The immunostimulating activities of mucilage fraction from yam were investigated. The proliferation of BSA-primed lymph node cells was enhanced between 4.1- to 10.9-fold compare to control, when cultured with 1 to $25{\mu}g/mL$ of yam-mucilage fraction. It showed strong immunostimulating activity than ginseng extract and as remarkable as Bifidobacterium adolescentis M101-4 known as a positive immunostimulator. Mitogenicity to lymph node cells was fully induced by concanavalin A and lipopolysaccharide. The proliferation of splenocytes and Peyer's patch cells was enhanced between 5.0- to 14.1-fold and 2.4- to 6.4-fold, respectively, when cultured with 1 to $25{\mu}g/mL$ of yam-mucilage fraction. It enhanced the production of cytokines such as tumor necrosis $factor-{\alpha}$ and IL-6 in the culture of RAW 264.7 macrophage cells. In the culture of lipopolysaccharide-stimulated RAW 264.7 cells, production of cytokines was as similar as compared to controls. In unstimulated RAW 264.7 cells, both tumor necrosis $factor-{\alpha}$ and IL-6 production were enhanced between 15.6- to 60.1-fold and 2.3- to 9.1-fold, respectively. Mucilage fraction from yam is expected to be a safe immunopotentiator to maintain the host immunity and develop a physiologically functional food.

• Korean journal of food and cookery science
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• v.14 no.4
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• pp.333-338
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• 1998

On the mutagenicity induced by 2-aminofluorene (2-AF) with S9 mix and N-Methyl-N＇-Nitro-N-Nitrosoguanidine (MNNG) without S9 mix, the antimutagenic effects of dietary fiber (total dietary fiber, u-cellulose and pectin) from Yam were examined by the Ames assay using Salmonella typhimurium TA98 and TA100. Total dietary fiber, $\alpha$-cellulose ind pectin from natural and cultural Yam didn＇t have mutagenicity. Most of sample dietary fiber showed the antimutagenicity. Total dietary fiber from cultural Yam was more effective than that from natural Yam on mutagenicity induced by 2-AF and MNNG. $\alpha$-cellulose from cultural Yam was more effective than that from natural Yam on mutagenicity caused by 2-AF and MNNG. Pectin from natural and cultural Yam had antimutagenic effect on mutagenicity induced by MNNG. In this study, antimutagenicity on MNNG was more effective than that on 2-AF. Antimutagenic effect of Samples had influence on incubation time. $\alpha$-cellulose and pectin from natural and cultural Yam showed stronger antimutagenic effect than standard $\alpha$-cellulose and standard pectin, respectively, on mutagenicity induced by 2-AF and MNNG.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.1
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• pp.8-14
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• 2011

The effect of flooding and soil salinity on the growth of yam (Dioscorea batatas) were studied on the experimantal site temporally established in the south-eastern part of Saemangeum Reclaimed Tidal Land (near Gwanghwal myun, Gimjae-gun, Jellabukdo, Korea). Yam seedlings planted by using aerial bulblet as alternative of sliced tubers, were grown for 20-days and transplanted in black-vinyl mulched ridges (about 20 cm in height) at 70cm interval by $20{\times}60cm$ spacing in the $4^{th}$ of May, 2010. Soil salinity was maintained at lower than 1.2 ds $m^{-1}$ during the growing period and did not result to salt injury in all plants. However, flooding injury very seriously led to plant death and plant mortality rates at $67{\pm}21$ and $82{\pm}9%$ of yam plants in the compost and no compost treatment, respectively, died by heavy flooding during the rainy summer season. The main reasons of the flooding injury included the decreased rainfall acceptable capacity (RAC) after the rising of water table and a slowdown of water infiltration rate after the formation of an impermeable soil crust in the furrow bottom with continuous and heavy downpour during the rainy summer season. The effect of compost treatment was not statistically observed because of the severe spatial difference caused by wet injury, although yam tuber yield was higher at 30 kg $10^{-1}$ in the compost treatment than in the no-compost treatment at 20 kg $10^{-1}$. However, the size of tuber ranged at 1.23 to 1.60 cm in diameter and 3.7 to 5.0 cm in length in all both treatment, which means they are still reproducible for the next cropping season. Conclusively, proper counter-flooding measure and soil salinity control critically important for successful yam production in Saemangeum Reclaimed Tidal Land.