• Title/Summary/Keyword: GC analysis

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Analysis of Aroma Patterns in Muskmelon at Different Storage Temperatures Using a Mass Spectrometry-based Electronic Nose (질량분석기 기반 전자코를 이용한 저장 온도별 머스크멜론의 향기 패턴 분석)

  • Youn, Aye-Ree;Noh, Bong-Soo;Kim, Byeong-Sam;Kwon, Ki-Hyun;Kim, Jong-Hoon;Kim, Sang-Hee;Choi, Duck-Joo;Cha, Hwan-Soo
    • Korean Journal of Food Science and Technology
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    • v.43 no.4
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    • pp.419-425
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    • 2011
  • Changes in the flavor of muskmelons stored at different temperatures were examined to judge aroma patterns during storage. A mass-spectrometry based electric nose was used to distinguish the subtle differences in the muskmelon's volatile compounds. The data were used for a discriminant function analysis (DFA), and then the partial least square algorithm was used for a quantitative analysis. Volatile components in the muskmelons increased with storage, and the first discriminant function score (DF1: $r^2$=99.88%, F=3072.5) moved from a positive position to a negative position as the storage period increased. The proper point of maturity was anticipated as the $28^{th}$ day at 0$^{\circ}C$, $21^{st}C$ day at 4 and 7$^{\circ}C$, and $14^{th}$ day at 10$^{\circ}C$. Also, using the DF1 score we could predict the general tendency (vitamin C, stem moisture, acidity) of the muskmelons. The electronic nose revealed that the major volatile compounds that changed during storage of the melons were ethyl ethyl acetate, butyl acetate, nonanol, dodecanoic acid, hexadecanoic acid and tricosane. The amount of volatile compounds detected increased during storage.

Analysis of benthic macroinvertebrates community stability and similarity in the Giran stream (길안천 저서성대형무척추동물의 군집안정성 및 유사도 분석)

  • Jang, Myeong Seong;Seo, Eul Won;Lee, Jong Eun
    • Korean Journal of Environmental Biology
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    • v.38 no.4
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    • pp.714-723
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    • 2020
  • This study was conducted to investigate the community stability and similarity of benthic macroinvertebrates in the Giran stream between August and September 2018, and compare results to those reported by Lee (2004). As relates to the total number of species in each taxon in 2018, 45 species were additionally discovered compared to the 2003 study; the number of EPT taxa increased by 14 species and OCH taxa increased by 18 species. The diversity and richness indexes increased while the dominance index tended to decrease. According to analysis of functional feeding groups, 11 more Gathering-collector species were found, making it the highest functional feeding group with 24 species. According to analysis of functional habitat groups, 15 more clinger species were found than in the past, making it the highest functional habitat group with 41 species. A community stability comparison showed that species belonging to 'Stability Group I' had the highest stability rate at 57.1% in 2003 and 61.5% in 2018. According to the biological water quality assessment, in 2018, the average water quality level at each survey site was 'Ia' and 'Very Good' in terms of environmental conditions. As a result of the similarity analysis between the survey points for the species that appeared, two large groups of similarities were classified (similarity group 1: 2003 sites, similarity group 2: 2018 sites).

A Study of the Predictive Effectiveness of Stem and Root Extracts of Cannabis sativa L. Through Network Pharmacological Analysis (네트워크 분석기반을 통한 대마 줄기 및 뿌리 추출물의 약리효능 예측연구)

  • Myung-Ja Shin;Min-Ho Cha
    • Journal of Life Science
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    • v.34 no.3
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    • pp.179-190
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    • 2024
  • Cannabis sativa is a plant widely cultivated worldwide and has been used as a material for food, medicine, building materials and cosmetics. In this study, we assessed the functional effects of C. sativa stem and root extracts using network pharmacology and confirmed their novel functions. The components in stem and root ethanol extracts were identified by gas chromatography-mass spectrometry analysis, and networks between the components and proteins were constructed using the STICHI database. Functional annotation of the proteins was performed using the KEGG pathway. The effects of the extracts were confirmed in lysophosphatidylcholine-induced THP-1 cells using real-time PCR. A total of 21 and 32 components were identified in stem and root extracts, respectively, and 147 and 184 proteins were linked to stem and root components, respectively. KEGG pathway analysis showed that 69 pathways, including the MAPK signaling pathway, were commonly affected by the extracts. Further investigation using pathway networks revealed that terpenoid backbone biosynthesis was likely affected by the extracts, and the expression of the MVK and MVD genes, key proteins in terpenoid backbone biosynthesis, was decreased in LPC-induced THP-1 cells. Therefore, this study determined the diverse function of C. sativa extracts, providing information for predicting and researching the effects of C. sativa.

Effects of Base Changes at the Transcription Start Site on Stringent Control of rnpB in Escherichia coli

  • Choi, Hyun-Sook;Park, Jeong Won;Hong, Soon Kang;Lee, Kangseok;Lee, Younghoon
    • Molecules and Cells
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    • v.26 no.2
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    • pp.212-215
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    • 2008
  • The GC-rich discriminator sequence between the -10 region and the transcription start site of the rnpB promoter is responsible for stringent control of M1 RNA synthesis. The rnpB promoter also contains a G nucleotide at the previously identified transcription start site. In this study, we examined by mutagenesis of G to A whether this +1G nucleotide is involved in the stringent response. We found that the change did not alter the stringent response. Since the +1 mutation might alter transcription initiation, we compared the transcription start sites of the wt and mutant promoters by primer extension analysis. Surprisingly, we found that wild type rnpB transcription starts at both the +1G position (70%) and the -1C position (30%), and that the +1A mutation led to transcription initiation exclusively at the -1C position. We also generated two transversion mutations at the -1 position, both of which led to transcription starting exclusively at that position. The -1G mutant promoter gave a stringent signal similar to the wild-type, whereas the -1A mutant generated a significantly less stringent signal. Base on these results, we propose that a short sequence, up to 7 bp downstream of the -10 region, is involved in the stringent response of the rnpB promoter.

A Study on Detection Characteristics of Cadmium and Lead for Bi Nanopowder-Labeled Electrode (비스무스 나노분말 표지 전극의 카드뮴/납 검출특성에 관한 연구)

  • Lee, Gyeoung-Ja;Kim, Hyoun-Jin;Lee, Hi-Min;Lee, Sang-Hoon;Lee, Min-Ku;Lee, Chang-Kyu
    • Journal of Powder Materials
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    • v.15 no.5
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    • pp.393-398
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    • 2008
  • Trace analysis of Cd and Pb at surface modified thick film graphite electrode with Bi nanopowder has been carried out using square-wave anodic stripping voltammetry (SWASV) technique. Bi nanopowder synthesized by gas condensation (GC) method showed the size of $50{\sim}100$ nm with BET surface area, $A_{BET}=6.8m^{2}g^{-l}$. For a strong adhesion of the Bi nanopowder onto the screen printed carbon paste electrode, nafion solution was added into Bi-containing suspension. From the SWASV, it was found that the Bi nanopowder electrode exhibited a well-defined responses relating to the oxidations of Cd and Pb. The current peak intensity increased with increasing concentration of Cd and Pb. From the linear relationship between Cd/Pb concentrations and peak current, the sensitivity of the Bi nanopowder electrode was quantitatively estimated. The detection limit of the electrode was estimated to be $0.15{\mu}g/l$ and $0.07{\mu}g/l$ for Cd and Pb, respectively, on the basis of the signal-to-noise characteristics (S/N=3) of the response for the $1.0{\mu}g/l$ solution under a 10 min accumulation.

Association of rs1042522 Polymorphism with Increased Risk of Prostate Adenocarcinoma in the Pakistani Population and its HuGE Review

  • Khan, Mohammad Haroon;Rashid, Hamid;Mansoor, Qaiser;Hameed, Abdul;Ismail, Muhammad
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.9
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    • pp.3973-3980
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    • 2014
  • Prostate adenocarcinoma is one of the leading causes of cancer related mortality in men but still limited knowledge is available about its associated functional SNPs including rs1042522 (Pro72Arg). The present study was undertaken to explore the association of this SNP with susceptibility to prostate adenocarcinoma along with its structural and functional impacts in the Pakistani population in a case-control study. Three-dimensional structure of human TP53 with Pro72Arg polymorphism was predicted through homology modeling, refined and validated for detailed structure-based assessment. We also carried out a HuGE review of the previous available data for this polymorphism. Different genetic models were used to evaluate the genotypes association with the increased risk of PCa (Allelic contrast: OR=0.0.34, 95%CI 0.24-0.50, p=0.000; GG vs CC: OR=0.17, 95%CI 0.08-0.38, p=0.000; Homozygous: OR=0.08, 95%CI 0.04-0.15, p=0.000; GC vs CC: OR=2.14, 95%CI 1.01-4.51, p=0.046; Recessive model: OR=0.10, 95%CI 0.05-0.18, p=0.000; Log Additive: OR=3.54, 95%CI 2.13-5.89, p=0.000) except the Dominant model (OR=0.77, 95%CI 0.39-1.52, p=0.46). Structure and functional analysis revealed that the SNP in the proline rich domain is responsible for interaction with HRMT1L2 and WWOX. In conclusion, it was observed that the Arg coding G allele is highly associated with increased risk of prostate adenocarcinoma in the Pakistani population (p=0.000).

Analysis of Fatty Acid Composition and Methyl-ester Properties of Camellia and Tea Oil (동백나무와 차나무 기름의 지방산 조성 및 메틸에스테르 특성 분석)

  • Kim, Kwang-Soo;Lee, Yong-Hwa;Jang, Young-Seok;Choi, In-Hu
    • New & Renewable Energy
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    • v.9 no.3
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    • pp.36-42
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    • 2013
  • To secure raw materials of biodiesel production, the possibility of camellia (C. japonica L.) and tea (C. sinensis L.) seed oil was studied to produce biodiesel. In this research, crude oil contents and fatty acid compositions of seeds were analyzed by Solxlet and Gas chromatography (GC). The oil contents in the seeds of camellia were 69.8%~73.8%, and tea were 26.3%~29.4%. Among the fatty acids of camellia and tea oil, oleic acid was dominant. The unsaturated fatty acids accounted for 88.4% and 80.2% of the whole fatty acids of camellia and tea seed oil. Total seed oil content and fatty acid composition of tea seed were influenced by collecting date. Across maturation period, oil content of tea seed averaged 18.3% on $6^{th}$ September increasing to 27.9% by $11^{th}$ October. For largest seed yield and oil content, the optimum time to harvest tea is in middle october, and camellia is late september and thereafter. The extraction efficiency of oil from seeds by extraction methods was determined. Biodiesel were synthesized in 92.1~92.8% yields from camellia and tea oils by transesterification. The biodiesel was characterized by its physical and fuel properties including oxidation stability, iodine value and cold filter plugging point (CFPP). Oxidation stability of camellia was 8.6~8.8 hours and tea was 2.9~3.6 at $110^{\circ}C$. Camellia oil had considerably better oxidation stability and CFPP than tea oil.

The Effect of Lubricity Improvement by Biodiesel Components (바이오디젤 구성성분에 따른 윤활성향상 효과)

  • Lim, Young-Kwan;Park, So-Ra;Kim, Jong-Ryeol;Yim, Eui-Soon;Jung, Choong-Sub
    • Applied Chemistry for Engineering
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    • v.21 no.6
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    • pp.684-688
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    • 2010
  • Biodiesel produced from the reaction of methanol and triglyceride which is the main component of animal fats and vegetable oils is known for remarkable lubricity. In this study, the lubricity of 3 kinds of biodiesel came from vegetable oils such as soybean oil, palm oil, and perilla oil and 2 kind of biodiesel which were produced from beef tallow and pork lard were analyzed using HFRR (High frequency reciprocating rig). In HFRR test result, the lubricity of perilla and soybean's biodiesel was higher than other biodiesels. After analysis of biodiesel components by GC-MS and determination of the lubricity of pure biodiesel components using HFRR, it was found that a higher olefin content and long alkyl chaining biodiesel had an excellent lubricity property.

Attractiveness of Plautia stali (Hemiptera: Pentatomidae) Aggregation Pheromone Produced in Korea (국산 갈색날개노린재 집합페로몬의 유인력)

  • Jang, Sin-Ae;Cho, Jin-Hoon;Park, Chung-Gyoo
    • The Korean Journal of Pesticide Science
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    • v.14 no.2
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    • pp.164-169
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    • 2010
  • Methyl (E,E,Z)-2,4,6-decatrienoate is the aggregation pheromone of brown-winged stink bug Plautia stali (Hemiptera: Pentatomidae). Attractiveness of the pheromone synthesized in Korea was compared with that of synthesized in Japan in the field. A lure filled with hexane was used as a control treatment. Catches in trap baited with Korean pheromone was significantly higher than that baited with Japanese one only in one orchard out of three sweet persimmon orchards in 2008. However there was no difference in trap catches between Korean and Japanese pheromones at three sites in 2009. Gas chromatography analysis showed that the components of both pheromones were not different each other. Monitoring of P. stali seasonal fluctuation using Korean pheromone showed that the bugs were most captured in August, 2008 and in September, 2009.

A New Single Nucleotide Polymorphism in the IGF-I Gene and Its Association with Growth Traits in the Nanjiang Huang Goat

  • Zhang, Chunxiang;Zhang, Wei;Luo, Hailing;Yue, Wenbin;Gao, Mingyu;Jia, Zhihai
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.8
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    • pp.1073-1079
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    • 2008
  • The objectives of this study were to identify polymorphisms of insulin-like growth factor I (IGF-I) gene and to investigate their association with growth traits in Nanjiang Huang goats. Five hundred and ninety-two animals were used to detect the polymorphisms in the complete coding sequence, part of introns and the 5'-regulatory region of the IGF-I gene by means of PCR-SSCP. A new single nucleotide polymorphism (G to C transversion) was identified at intron 4 of the IGF-I gene in the goats. Two alleles and three genotypes were observed in this group. The frequency of G and C alleles was 54.6 and 45.4%, respectively. The statistical analysis showed that polymorphism of the IGF-I gene had a significant association (p<0.05) with birth weight (BW), body weight at 6 months (W6) and at 12 months (W12), heart girth at 2 months (G2), body length at 6 months (L6), wither height at 6 months (H6) and at 12 months (H12) and heart girth at 12 months (G12). The goats with genotype CC had significantly higher BW, W6, W12, G2, L6, H6, H12 and G12 than those with genotype GC and had significantly higher W12, H6, H12 and G12 than those with genotype GG. Therefore, genotype CC may be the most advantageous for growth traits in the Nanjiang Huang goat. However, no significant association between SNP genotypes and other growth traits was observed. These results indicated that the SNP marker of the IGF-I gene may be a potential molecular marker for growth traits in Nanjiang Huang goats.