• 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.

• 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.

• 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.

• KAPE Magazine
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• s.172
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• pp.70-71
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• 2010

• Journal of the Korean Applied Science and Technology
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• v.33 no.2
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• pp.324-332
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• 2016

The objective of this study was to investigate the antioxidant activity of Korean yam (Dioscorea batatas $D_{ECNE.}$) by different extraction solvents including 70% methanol, 70% ethanol and chloroform-methanol mixture (CM, 2:1, v/v). Raw yam was analyzed for its color property, total phenol content and antioxidant activity. Yam possessed high $L^*$ value and $H^{\circ}$ value, which were $81.64{\pm}2.59$ and $83.36{\pm}0.15$, respectively. Raw yam was found to have great antioxidant activity evaluated through ABTS [2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt] radical scavenging activity, DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, reducing power, and ferric reducing antioxidant power. Total phenol contents of various extracts from raw yam increased in the following order: 70% methanol extract ($37.62{\pm}0.88mg\;CAE/g$), 70% ethanol extract ($43.38{\pm}0.66mg\;CAE/g$) and CM extract ($67.17{\pm}0.12mg\;CAE/g$), respectively. The same trend was also could be found in the ABTS radical scavenging activity, DPPH radical scavenging activity and ferric reducing antioxidant power assays. These results implied that Korean yam might play an important role in antioxidation and serve as the bio-health functional food to take a good part in prevention of human diseases and aging.

• Journal of the Korean Applied Science and Technology
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• v.33 no.2
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• pp.391-400
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• 2016

The aim of this study was conducted to investigate the proximate and nutritional compositions including mineral, vitamin, amino acids and fatty acids in Korean yam (Dioscorea batatas $D_{ECNE}.$). Carbohydrate (68.1%) possessed the large single constituent of yam. Small amounts of crude protein (16.9%), crude ash (5.8%) and crude fat (2.0%) contents were found. Yam was found to be good sources of essential minerals such as K (1295.5 mg/100 g), Mg (115.3 mg/100 g), Na (99.0 mg/100 g) and Ca (56.5 mg/100 g) but Zn (0.3 mg/100 g) content was low. Relatively abundant vitamin $B_1$ (11.5 mg/100g) could be observed while vitamin A, $B_3$ and $B_6$ were not found. The amino acid analysis revealed that the yam was superior with respect to glutamic acid (1770.6 mg%), lysine (1210.6 mg%) and urea (550.9 mg%). Essential amino acids were calculated to be 2954.5 mg%. The amino acid profiles showed that yam to be limiting in valine and leusine. Palmitic acid and linoleic acid were the most predominant fatty acids with the value of 31.5% and 41.5%, respectively. And the polyunsaturated fatty acids including linoleic acid and linolenic acid were present in a large quantities in yam. And it also contained higher amounts of unsaturated fatty acids compared saturated fatty acids.

• 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.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.444-447
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• 2006

Yam powders were prepared by freeze, fan, hot-air, and coal-heat drying. The viscosities of their suspensions and supernatants and the viscosity changes with addition of sugar, salt, and citric acid were investigated. Viscosity (43 mPa s) of 7.5% suspension of fan-dried yam powder was lower than that of freeze dried yam (58.1 mPa s), but much higher than that of the conventional, hot-air dried yam (17.2 mP s). Coal-heat dried yam had a viscosity of only 4.5 mPa s. The viscosity was related to the protein denaturation induced by heat and acid. Addition of sugar to yam powder increased the viscosity of the suspension but no changes were evident with salt addition. Viscosities decreased when 0.5% citric acid was added (pH 3.4-3.5).

• Journal of the Korean Applied Science and Technology
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• v.32 no.1
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• pp.127-135
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• 2015

The aim of this study was to investigate the antioxidant activity of thermal treatment yam (Dioscorea batatas DECNE.) in Korea. Thermal treatment yam was extracted by different solvents including 70% methanol, 70% ethanol and chloroform-methanol mixture (CM, 2:1, v/v). Then color property, total phenol content and antioxidant activity were analyzed. Yam possessed high $L^*$ value and $H\limits^{\circ}$ value, which were $54.92{\pm}2.18$ and $73.20{\pm}0.77$, respectively. Thermal treatment yam exhibited great antioxidant activity evaluated by ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt] radical scavenging activity, DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, reducing power, and ferric reducing antioxidant power. Total phenol contents of various extracts from thermal treatment yam increased in the following order: 70% methanol extract ($63.53{\pm}0.33mg\;CAE/g$), 70% ethanol extract ($69.47{\pm}1.00mg\;CAE/g$) and CM extract ($97.49{\pm}0.66mg\;CAE/g$), respectively. The same trend was also could be found in antioxidant activity assays except for reducing power assay. These results implied that these extracts from thermal treatment yam might be useful to take a good part in prevention of human diseases and aging.

• 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.