• 식물병연구
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• 제24권4호
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• pp.292-301
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• 2018

Alternaria leaf spot disease has been a concern during a tomato production in greenhouse. In vitro antifungal activities of vapours of four plant essential oils, cinnamon oil, fennel oil, origanum oil and thyme oil, were investigated during in vitro conidial germination and mycelial growth of Alternaria alternata causing the tomato leaf spots to find eco-friendly alternatives for chemical fungicides. The four plant essential oils showed different antifungal activities against in vitro conidial germination of A. alternata in dose-dependent manners, and cinnamon oil vapour was most effective to suppress the conidial germination. The four plant essential oils showed similar antifungal activities against the in vitro mycelial growth of A. alternata in dose-dependent manners, but low doses of thyme oil vapour slightly increased in vitro mycelial growth of A. alternata. Necrotic lesions on the A. alternata-inoculated tomato leaves were reduced differently depending on kinds and concentrations of plant essential oils. Delayed conidial germination and germ-tube elongation of A. alternata were found on the tomato leaves treated with cinnamon oil and origanum oil vapours at 6 hpi. These results suggest that volatiles from cinnamon oil and origanum oil can be provided as alternatives to manage Alternaria leaf spot during the tomato production eco-friendly.

• 천문학회보
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• 제44권1호
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• pp.63.3-63.3
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• 2019

Active asteroids are celestial bodies that distinctively have asteroid-like orbital elements but show comet-like activity. They exhibit the activities due to the sublimation of volatile ices, impacts with small objects or break-up by rapid rotations. As of 2019 February, 30 active asteroids are detected in the outer main belt (i.e., the semimajor axes a>2.5 au) while only 3 of them in the inner main belt (a<2.5 au), suggesting that sublimation of remaining icy volatiles can be one of the most fundamental mechanisms for the activities. A sudden activity of (6478) Gault was reported in early 2019. The asteroid was discovered in 1988 and has exhibited its inactive appearance until the end of last year. Soon after the report, we have conducted imaging observations using the Seoul National University Observatory 1.0-m telescope and the Korea Microlensing Telescope Network (KMTNet) to monitor the activity. The observed images showed a primary dust tail that consists of dust grains ejected early November in 2018. Later, another tail developed, indicating further dust ejection occurred around late December 2018. Our model simulation to reproduce the morphology of the dust cloud suggests that the slightly-curved primary dust tail results from a continuous dust ejection over weeks. The total mass of ejecta was estimated to XX kg (XX% of the asteroid mass). Such continuous dust ejection for the inner active asteroids was unexpected because ice might have already sublimated from subsurfaces of inner main belt. Based on our observational evidence, we will discuss how inner asteroids are activated and eject dust continuously.

• Asian-Australasian Journal of Animal Sciences
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• 제32권6호
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• pp.881-890
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• 2019

Objective: A study was conducted to develop non-dairy creamer analogs/mimics using egg white, egg yolk, soy protein and their combinations, and their nutrient content, shelf-life and flavor acceptability were compared. Methods: Spray dried egg white, egg yolk, and soy protein isolate were purchased from manufacturers and used for the formulae. Results: The protein contents of the non-dairy creamer analogs/mimics were about 8.5% as calculated. The amounts of oleic and linoleic acid content increased as the amount of yolk increased in the formula, but the increases of polyunsaturated fatty acids were <0.5% of total fat. Addition of egg yolk to the formula increased choline and lutein content in the products, but the amounts were <0.4 mg/g for choline and $4{\mu}g/g$ for lutein. The lutein in the products continued to decrease over the storage time, and only about 15% to 20% of the 0-month amounts were left after 3 months of storage. Although the thiobarbituric acid reactive substances values of the spray-dried non-dairy creamer analogs/mimics increased as storage time increased, the values were still low. Yellowness, darkness, and egg flavor/odor of the non-dairy creamer analogs/mimics increased as the amount of egg yolk in the formula increased. The overall acceptability of the non-dairy creamer analogs/mimics was closely related to the intensity of egg flavor/odor, but storage improved their overall acceptance because most of the off-odor volatiles disappeared during the storage. Water temperature was the most important parameter in dissolving spray-dried non-dairy creamer analogs/mimics, and $55^{\circ}C$ to $75^{\circ}C$ was the optimal water temperature conditions to dissolve them. Conclusion: Higher amounts of yolk and soy protein combinations in place of egg white reduced the cost of the products significantly and those products contained better and balanced nutrients than the commercial coffee creamers. However, off-flavor and solubility were two important issues in the products.

• Natural Product Sciences
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• 제27권1호
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• pp.36-44
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• 2021

The essential oils from the aerial parts (leaves and flowers) of Spiraea hypericifolia L. (Rosaceae), collected in Northern Kazakhstan, were obtained by distillation in two dispersion media (distilled water and 15% NaCl solution). The chemical composition of the essential oils was evaluated by GC-MS for the first time. The yield of the essential oil was 0.04% (in fresh growth conditions) and 0.02% (in dry growth conditions) respectively regardless of which dispersion media (H2O or 15% NaCl solution) was used at the isolation of essential oil. The main compounds were aliphatic hydrocarbons (alkanes) (40.6-53.2%), aldehydes (8.4-17.4%), diterpenoids (9.1-16.7%) and ketones (6.2-8.7%). Content of monoterpenoids was depended on dispersion media (2.2-3.6% where H2O was dispersion media and 8.4-8.5% where 15% NaCl solution was dispersion media). n-Heneicosane (17.4-34.1%) and n-tricosane (14.3-19.5%) were the main constituents of the essential oil of S. hypericifolia. There were many insects from different classes in S. hypericifolia at flowering. Important components such as α-methylene-γ-butyrolactone (0.8-2.8%), benzyl cyanide (0.7-1.1%), β-damascenone (1.2-2.9%), (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (1.8-2.7%), β-ionone (0.5-1.8%) and others were detected in small amounts.

• 한국응용곤충학회지
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• 제61권1호
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• pp.35-50
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• 2022

본 종설에서는 벼와 옥수수, 콩과작물, 감자, 들깨, 참깨에 대한 주요 나비목 해충 22종의 성페로몬 조성에 대해 국내외에서 연구된 결과들을 비교하면서 성충 예찰 수단으로 활용 가능한지를 분석하여 간단하게 정리하였다. 이 중 4종의 국내 개체군에서는 성페로몬샘 추출물로부터 성페로몬 성분들이 동정되고, 야외실험을 통해 그 조성이 규명되었다. 다른 3종에 대해서는 국내 개체군을 이용한 페로몬 화합물의 화학적 동정과정은 없었으나, 보고된 성페로몬 성분들을 이용한 실내 및 야외에서의 세밀한 조성실험을 통해 국내 개체군에 대한 최적 예찰조성이 선발되었다. 일부 종에 대해서는 최적 예찰미끼 개발을 위해 성페로몬샘에서 발견되는 미량성분의 역할에 대해 검토할 필요가 있다.

• Animal Bioscience
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• 제36권7호
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• pp.1101-1119
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• 2023

Objective: This study aimed to evaluate the physicochemical, metabolomic, and sensory qualities of Chikso and Hanwoo beef during 28 days of wet aging. Methods: Rump and loins from Hanwoo and Chikso were obtained and wet-aged for 28 days at 4℃. The samples were collected at 7-day interval (n = 3 for each period). Physicochemical qualities including pH, meat color, shear force value, and myofibrillar fragmentation index, metabolomic profiles, and sensory attributes (volatile organic compounds and relative taste intensities) were measured. Results: Chikso showed a significantly higher shear force value than Hanwoo on day 0; however, no differences between breeds were found after day 14, regardless of the cuts. Overall, Chikso had more abundant metabolites than Hanwoo, especially L-carnitine and tyrosine. Among the volatiles, the ketone ratio was higher in the Chikso rump than the Hanwoo rump; however, Chikso had fewer alcohols and aldehydes than Hanwoo. Chikso rump showed higher taste intensities than the Hanwoo rump on day 0, and sourness decreased in Chikso, but increased in the Hanwoo rump on day 14. Wet aging for 14 days intensified the taste of Chikso loin but reduced the umami intensity of Hanwoo loin. Conclusion: Chikso had different metabolomic and sensory characteristics compared to Hanwoo cattle, and 14 days of wet aging could improve its tenderness and flavor traits.

• 한국축산식품학회지
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• 제42권2호
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• pp.240-251
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• 2022

Fat deposition in animal muscles differs according to the genetics and muscle anatomical locations. Moreover, different fat to lean muscle ratios (quality grade, QG) might contribute to aroma development in highly marbled beef. Scientific evidence is required to determine whether the abundance of aroma volatiles is positively correlated with the amount of fat in highly marbled beef. Therefore, this study aims to investigate the effect of QG on beef aroma profile using electronic nose data and a chemometric approach. An electronic nose with metal oxide semiconductors was used, and discrimination was performed using multivariate analysis, including principal component analysis and hierarchical clustering. The M. longissimus lumborum (striploin) of QG 1++, 1+, 1, and 2 of Hanwoo steers (n=6), finished under identical feeding systems on similar farms, were used. In contrast to the proportion of monounsaturated fatty acids (MUFAs), the abundance of volatile compounds and the proportion of polyunsaturated fatty acids (PUFAs) decreased as the QG increased. The aroma profile of striploin from carcasses of different QGs was well-discriminated. QG1++ was close to QG1+, while QG1 and QG2 were within a cluster. In conclusion, aroma development in beef is strongly influenced by fat deposition, particularly the fat-to-lean muscle ratio with regard to the proportion of PUFA. As MUFA slows down the oxidation and release of volatile compounds, leaner beef containing a higher proportion of PUFA produces more volatile compounds than beef with a higher amount of intramuscular fat.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 춘계학술대회
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• pp.109-109
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• 2020

꽃차(Flower tea)는 최근 다양한 제품이 개발되고 소비가 확대되는 등 그 산업적 가치가 증대하고 있다. 꽃차의 향기 특성은 우렸을 때 나타나는 색깔 및 인체에서의 생리활성과 더불어 주요한 꽃차 품질결정 요소이다. 본 연구는 꽃차로의 이용이 활발한 국화과 식물 중 구절초(Dendranthema zawadskii var. latilobum), 국화(Chrysanthemum morifolium), 노랑색 및 주황색 마리골드(Tagetes erecta 'Yellow' and 'Orange'), 그리고 캐모마일(Matricaria chamomilla)의 향기 성분특성을 구명하기 위하여 제조된 꽃차를 headspace-solidphase microextraction/gas chromatography-mass spectrometry (HS-SPME/GC-MS)를 이용하여 분리, 동정하였다. 국화과 꽃차로부터 총 117종의 휘발성 성분이 확인되었는데, 각 꽃차 종류별 동정된 휘발성 성분의 개수, 주요 3개 휘발성 성분과 전체 향기성분 peak중 이들이 차지하는 구성비율(%)은 다음과 같았다: 구절초 64종, camphor (31%), α-pinene(14%), camphene(14%); 국화 60종, camphor(15%), chrysantheny acetate(13%), eucalyptol (11%); 마리골드 '옐로우' 53종, 2,4-heptadienal(26%), trans-isocarveol(21%), cis-β-Copaene(18%); 마리골드 '오렌지' 61종, β-caryophyllene(16%), β-ocimene epoxide(12%), β-ocimene(12%); 캐모마일 50종, β-farnesene(63%), nonane(9%), spathulenol(5%). 국화과 꽃차 5종 모두에서 공통적으로 검출된 성분은 β-caryophyllene, α-pinene, β-farnesene 등 10종이었으며 마리골리 '옐로'는 '오렌지'와 주요 향기성분의 조성에서 뚜렷한 차이를 나타내었다. 비록 그 함량은 낮았으나 구절초, 국화, 마리골드 '오렌지', 그리고 캐모마일은 각각 10종, 12종, 3종 및 13종이었다. 마리골드 '엘로'의 경우 검출된 모든 향기성분은 마리골드 '오렌지'나 다른 국화과 식물의 꽃차에서도 검출된 바, 향기 성분이 다양성이 다소 낮게 나타났다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 춘계학술대회
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• pp.110-110
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• 2020

꽃을 우려내어 차로 마시는 꽃차(flower tea)는 꽃이 가진 색과 향, 맛과 모양을 즐길 수 있어 최근 수요가 급증하고 있다. 본 연구는 매화(Prunus mume), 장미(Rosa spp.), 그리고 해당화(Rosa rugosa) 등 3종의 장미과 식물의 꽃차의 향기 성분 특성을 구명코자 꽃차를 headspace vial에 담은 후 solid phase microextraction(SPME)를 이용하여 추출한 후 gas chromatography-mass spectrometry를 이용하여 휘발성 성분을 분리하였다. 분리된 각 성분은 deconvolution 과정을 수행한 후 NIST masss spectral library를 이용하여 동정하였다. 매화꽃차에서는 총 58개의 휘발성 성분이 검출되었는데, benzaldehye와 nonane, 그리고 phenylmethanol이 주요 구성 성분으로 검출된 전체 휘발성 성분의 각각 64.7%, 16.1% 및 4.7%를 차지하고 있었다. 장미 꽃차의 경우 검출된 35종 중 주요 구성 성분은 nonane과 2-phenylethanol, 그리고 phenylmethanol로서 각각 전체 성분 중 54.0%, 18.0% 및 4.6%를 구성하고 있었다. 해당화 꽃차의 경우는 장미 꽃차와 동일하게 2-phenylethanol(62.2%)과 nonane(20.1%)이 주요 성분으로 동정되었으며 이들 2 성분의 합이 전체 43개 휘발성 성분의 82.3%를 차지하는 것으로 나타났다. 본 연구에 사용된 매화, 장미, 해당화 등 장미과 식물 3종의 꽃차 모두에서 공통적으로 검출된 휘발성 성분은 앞서 각 꽃차 종류별 주요 성분으로 언급된 4종의 성분을 포함하여 19종이었으며 매화꽃차에서만 검출된 성분은 29종으로 장미꽃차(6종)와 해당화 꽃차(8종)보다 향기성분의 다양성이 높은 것으로 나타났다.

• Advances in materials Research
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• 제13권3호
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• pp.161-171
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• 2024

This study aimed to investigate the effect of physicochemical properties and mix ratios of iron ore (oxide feed): coke (reductant) on the carbothermic reductions of iron ore. Coke size was fixed at ≤63 ㎛ while iron ore size varied between 150-63 ㎛ and ≤63 ㎛ respectively. Mix ratios were changed from 100:0 (reference) to 80:20 and 60:40 while the temperature, heating rate and soaking duration in muffle furnace were fixed at 1100 ℃, 10 ℃/min and 1 hour. Particle size analyzer, XRF, CHNS and XRD analyses were used for determination of raw feed characteristics. The occurrence of phase transformations from various forms of iron oxides to iron during the carbothermal reductions were identified through XRD profiles and supported with weight loss (%). XRF analysis proved that iron ore is of high grade with 93.4% of Fe₂O₃ content. Other oxides present in minor amounts are 2% Al₂O₃ and 1.8% SiO₂ with negligible amounts of other compounds such as MnO, K₂O and CuO. Composite pellet with finer size iron particles (≤63 ㎛) and higher carbon content of 60:40 exhibited 45.13% weight lost compared to 32.30% and 3.88% respectively for 80:20 and 100:0 ratios. It is evident that reduction reactions can only occur with the presence of coke, the carbon supply. The small weight loss of 3.88% at 100:0 ratio occurs due to the removal of moisture and volatiles and oxidations of iron ore. Higher carbon supply at 60:40 leads into better heat and mass transfer and diffusivity during carbothermic reductions. Overall, finer particle size and higher carbon supply improves reactivity and gas-solid interactions resulting in increased reductions and phase transformations.