• 제목/요약/키워드: $C_4$ plant

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Efficiency for extracting icariin from Epimedium koreanum Nakai by temperature and solvent variations

  • Baek, Hum-Young;Lee, Young-Sang
    • Plant Resources
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    • 제6권3호
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    • pp.221-226
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    • 2003
  • To improve industrial scale extraction method for extraction of icariin from Epimedium koreanum Nakai, the yields under different extracting conditions such as solvent, temperature, duration and solvent to plant material weight ratio were compared. Regarding extracting solution, highest extracts and icariin yield could be achieved when 10% EtOH was used. In case of plant material to extracting solvent ratio, no significant differences could be observed from 1/10 to 1/50, indicating 1/10 was the most efficient. Extracting temperature significantly affected extracts and icariin yields in that 9$0^{\circ}C$ increased the collected extracts and icariin contents up to 29.6% and 0.76%, respectively, compared to 27.2%, 0.33% at 7$0^{\circ}C$. The yield of extracts was less dependent upon extracting temperature compared to icariin yield. Regarding extraction time, 4 hr and 6 hr resulted in high extracts and icariin yield, respectively. We found extracting Epimedium koreanum Nakai in 10 times volume of 10% EtOH for 4 and 6 hr at 9$0^{\circ}C$ seem to be relatively efficient methods for extracts and icariin, respectively.

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국내 시판우유의 보관방법별 품질변화에 관한 연구

  • 정석찬;김계희;정명은;김성일;변성근;이득신;박성원;조남인;김옥경
    • 한국유가공학회:학술대회논문집
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    • 한국유가공기술과학회 2002년도 정기총회 및 제55회 추계심포지움 - 전환기 유가공 산업의 생존전략
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    • pp.23-40
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    • 2002
  • This study was conducted to investigate the quality changes of the UHT(ultra-high temperature), LTLT(law temperature long time) and HTST(high temperature short time) treated milk samples by storage conditions for 6 months from August 2000 to February 2001. The UHT treated milk samples collected from 3 plants(A, B and C) were stored at l0$^{\circ}$C and room temperature(dark and light exposure) for 6 months, and the LTLT and HTST treated milk samples(D and E) were also stored for 30 days. The UHT pasteurized milk of A, B and C plant was treated at 130$^{\circ}$C for 2-3s, 133$^{\circ}$C for 2-3s and 135$^{\circ}$C for 4s, respectively. The UHT sterilized milk of A and B plant was treated at 140$^{\circ}$C for 2-3s and 145$^{\circ}$C for 3-4s, respectively. The LTLT milk of D plant was treated at 63$^{\circ}$C for 30 mins, and the HTST milk of E plant was treated at 72$^{\circ}$C for 15s. All of the raw milk samples collected from storage tank in 5 milk plants were showed less than 4.0 X 10$^5$cfu/ml in standard plate count, and normal level in acidity, specific gravity, and component of milk. Preservatives, antibiotics, sulfonamides and available chloride were not detected in both raw and heat treated milk samples obtained from 5 plants. One(10%) of 10 UHT pasteurized milk samples obtained from B plant and 2 (20%) of 10 from C were not detected in bacterial count after storage at 37$^{\circ}$C for 14 days, but all of the 10 milk samples from A were detected. No coliforms were detected in all samples tested. No bacteria were also detected in carton, polyethylene and tetra packs collected from the milk plants. A total of 300 UHT pasteurized milk samples collected from 3 plants were stored at room(3$^{\circ}$C ${\sim}$ 30$^{\circ}$C) for 3 and 6 months, 11.3%(34/300) were kept normal in sensory test, and 10.7%(32/300)were negative in bacterial count. The UHT pasteurized milk from A deteriorated faster than the UHT pasteurized milk from B and C. The bacterial counts in the UHT pasteurized milk samples stored at 10$^{\circ}$C were kept less than standard limit(2 ${\times}$ 10$^4$ cfu/ml) of bacteria for 5 days, and bacterial counts in some milk samples were a slightly increased more than the standard limit as time elapsed for 6 months. When the milk samples were stored at room(3$^{\circ}$C ${\sim}$ 30$^{\circ}$C), the bacterial counts in most of the milk samples from A plant were more than the standard limit after 3 days of storage, but in the 20%${\sim}$30%(4${\sim}$6/20) of the milk samples from B and C were less than the standard limit after 6 months of storage. The bacterial counts in the LTLT and HTST pasteurized milk samples were about 4.0 ${\times}$ 10$^3$ and 1.5 ${\times}$ 101CFU/ml at the production day, respectively. The bacterial counts in the samples were rapidly increased to more than 10$^7$ CFU/ml at room temperature(12$^{\circ}$C ${\sim}$ 30$^{\circ}$C) for 3 days, but were kept less than 2 ${\times}$ 10$^3$ CFU/ml at refrigerator(l0$^{\circ}$C) for 7 days of storage. The sensory quality and acidity of pasteurized milk were gradually changed in proportion to bacterial counts during storage at room temperature and 10$^{\circ}$C for 30 days or 6 months. The standard limit of bacteria in whole market milk was more sensitive than those of sensory and chemical test as standards to determine the unaccepted milk. No significant correlation was found in keeping quality of the milk samples between dark and light exposure at room for 30 days or 6 months. The compositions of fat, solids not fat, protein and lactose in milk samples were not significantly changed according to the storage conditions and time for 30 days or 6 months. The UHT sterilized milk samples(A plant ; 20 samples, B plant ; 110 samples) collected from 2 plants were not changed sensory, chemical and microbiological quality by storage conditions for 6 months, but only one sample from B was detected the bacteria after 60 days of storage. The shelflife of UHT pasteurized milk in this study was a little longer than that reported by previous surveys. Although the shelflife of UHT pasteurized milk made a significant difference among three milk plants, the results indicated that some UHT pasteurized milk in polyethylene coated carton pack could be stored at room temperature for 6 months. The LTLT and HTST pasteurized milk should be sanitarily handled, kept and transported under refrigerated condition(below 7$^{\circ}$C) in order to supply wholesome milk to consumers.

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멕시코만 코어 퇴적물(ODP 625B)의 식물왁스 탄화수소(n-alkanes)와 지방산(n-alkanoic acids)의 생성기원 비교 연구 (Contrasting Sources of Plant Wax n-alkanes and n-alkanoic Acids in Gulf of Mexico Sediments (ODP 625B))

  • 서연지
    • Ocean and Polar Research
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    • 제41권2호
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    • pp.89-97
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    • 2019
  • Long chain plant waxes (n-alkanes, n-alkanoic acids, and n-alcohols) and their carbon isotopic compositions (${\delta}^{13}C$) in geologic archives are valuable tools for paleovegetation reconstruction. However, the sensitivity of different plant wax constituents to vegetation shift is not well understood. This study explores controls on the variation in ${\delta}^{13}C$ values of long-chain n-alkanes ($C_{27}$ to $C_{33}$) and n-alkanoic acids ($C_{26}-C_{30}$) in the Gulf of Mexico core sediments (ODP 625B) near the Mississippi River delta. n-Alkanoic acids' ${\delta}^{13}C$ values were higher than those of n-alkanes by 1-2‰ on average and such a pattern is the opposite from their isotope fractionation observed in living plants: 1-2‰ smaller in n-alkanes than n-alkanoic acids. We attribute this offset to contributions from aquatic plants or microbes that produce high concentrations of $^{13}C-enriched$ long-chain n-alkanoic acids. The sensitivity of n-alkanes and n-alkanoic acids to vegetation and climate varied among chain lengths. The $n-C_{33}$ alkanes were most sensitive to $C_4$ grassland expansion among n-alkane homologues, while no specific trend was observed in n-alkanoic acids. This is due to the similarity in n-alkanoic acid concentrations between $C_3$ and $C_4$ plants by homologues and low terrestrial plant-derived n-alkanoic acid contributions to the sediments. The results of this study suggest that long chain n-alkanoic acids' ${\delta}^{13}C$ values in sediments may be influenced by contributions from different sources such as aquatic plants or microbial inputs and therefore interpretations regarding this matter should be cautiously formulated. We suggest that there is a need for further studies on characterizing long-chain n-alkanoic acids ($C_{26}-C_{34}$) in aquatic plants and microbes from various climates and environments in order to investigate their production and integration into sedimentary archives.

Synthetis of 4H,6H-Furo[3,4-c]isoxazole Derivatives as New Potent Fungicides and Their Structure Activity Relationship

  • 김형진;황광진;이재현
    • Bulletin of the Korean Chemical Society
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    • 제18권5호
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    • pp.534-540
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    • 1997
  • 4H,6H-Furo[3,4-c]isoxazoles (Ⅰ-Ⅳ), potential fungicides, have been designed and synthesized via intramolecular [2+3] cycloaddition of nitroalkyne 3 as a key step. The broad spectrum of fungicidal activities of furoisoxazoles (Ⅰ-Ⅳ) were observed on plant pathogens at 250 ppm. Furoisoxazoles Ⅱ, Ⅲ with chlorophenyl at 6-position and methyl or alkylated oxime group at 3-position gave effective control of plant diseases. The furoisoxazole Ⅳ with a chlorophenyl group at 4-position also resulted in high fungicidal activities.

Molecular Cloning, Characterization and Functional Analysis of a 2C-methyl-D-erythritol 2, 4-cyclodiphosphate Synthase Gene from Ginkgo biloba

  • Gao, Shi;Lin, Juan;Liu, Xuefen;Deng, Zhongxiang;Li, Yingjun;Sun, Xiaofen;Tang, Kexuan
    • BMB Reports
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    • 제39권5호
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    • pp.502-510
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    • 2006
  • 2C-methyl-D-erythritol 2, 4-cyclodiphosphate synthase (MECPS, EC: 4.6.1.12) is the fifth enzyme of the non-mevalonate terpenoid pathway for isopentenyl diphosphate biosynthesis and is involved in the methylerythritol phosphate (MEP) pathway for ginkgolide biosynthesis. The full-length mecps cDNA sequence (designated as Gbmecps) was cloned and characterized for the first time from gymnosperm plant species, Ginkgo biloba, using RACE (rapid amplification of cDNA ends) technique. The full-length cDNA of Gbmecps was 874 bp containing a 720 bp open reading frame (ORF) encoding a peptide of 239 amino acids with a calculated molecular mass of 26.03 kDa and an isoelectric point of 8.83. Comparative and bioinformatic analyses revealed that GbMECPS showed extensive homology with MECPSs from other species and contained conserved residues owned by the MECPS protein family. Phylogenetic analysis indicated that GbMECPS was more ancient than other plant MECPSs. Tissue expression pattern analysis indicated that GbMECPS expressed the highest in roots, followed by in leaves, and the lowest in seeds. The color complementation assay indicated that GbMECPS could accelerate the accumulation of $\beta$-carotene. The cloning, characterization and functional analysis of GbMECPS will be helpful to understand more about the role of MECPS involved in the ginkgolides biosynthesis at the molecular level.

돈적리 균의 분리, 검출을 위한 수송배지의 비교 (Comparison of transport media for the isolation and detection of Brachyspira hyodysenteriae)

  • 조세지;김종완;김하영;오상익;정소정;정지아;조아라;이명헌;조호성;변재원
    • 대한수의학회지
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    • 제55권1호
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    • pp.9-12
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    • 2015
  • Brachyspira (B.) hyodysenteriae is a causative agent of swine dysentery that is responsible for death and economic losses in the pig industry. It is imperative that clinical samples be delivered fresh for accurate diagnosis. The viability and DNA detection of B. hyodysenteriae using lab-made (phosphate buffered saline and modified tryptic soy broth) or commercial transport media (C, D, and E) were compared by culturing and real-time PCR at $4^{\circ}C$ or room temperature (RT), respectively. B. hyodysenteriae grown in D (Anaerobe Systems, USA) and E (Starplex Scientific, Canada) media was viable for 4 days at $4^{\circ}C$ and RT. However, B. hyodysenteriae in A, B, and C (culture swab; BD Biosciences, USA) media were not recovered after 2 days at RT. Ct values for real-time PCR at $4^{\circ}C$ and RT ranged from $27.2{\pm}2.1$ (C) to $29.6{\pm}0.5$ (B), and $28.0{\pm}0.9$ (E) to $30.2{\pm}1.5$ (B), respectively. Considering the field conditions, it is important that transport media is used for specimen isolation and PCR to obtain an accurate diagnosis of swine dysentery.

담배 모자이크 바이러스 고추계통(TMV-P)의 외피단백질 유전자를 도입한 형질전환 담배의 TMV-P에 대한 반응 (Responses to Infection of Tobacco Mosaic Virus Pepper Strain (TMV-P) in Transgenic Tobacco Plants Expressing the TMV-P Coat Protein or Its Antisense RNA)

  • 최장경;홍은주;이재열;장무웅
    • 한국식물병리학회지
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    • 제11권4호
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    • pp.374-379
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    • 1995
  • The cDNA of tobacco mosaic virus-pepper strain (TMV-P) coat protein (CP) genes were introduced into tobacco plants (Nicotiana tabacum cv. Samsun nn) using a binary Ti plasmid vector of Agrobacterium tumefaciens. these cDNAs introduced into tobacco plants were detected by polymerase chain reaction. Symptom development was distinctly suppressed in the transgenic plant introduced buy sense CP cDNA when the plant was inoculated with TMV-P, while in transgenic tobacco plants of antisense CP gene, symptom development was not suppressed as in non-transgenic plants. TMV-P concentration in the sense CP transgenic tobacco plant was decreased to 1/14 of the concentration in non-transgenic plants. Expression of the kanamycin resistance gene of these transgenic plants could be detected in the progeny.

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적예가 인삼의 광합성 및 생육에 미치는 영향 (Effect of Fruits Removal on the Photosynthesis and the Growth of Ginseng Plant (Punax ginseng C. A. MEYER))

  • 양덕조;이성식;김요태
    • Journal of Ginseng Research
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    • 제6권1호
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    • pp.1-10
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    • 1982
  • This study was conducted to determine effect of fruits removal on the CO2 exchange rates (CER) and growth of ginseng plant. Fruit of 2, 4 age plant removed at 7, May. The results of these investigations are as follows. 1. The net photosynthetic rates of the ginseng bearing fruits increased to a considerably greater degree than that of the ginseng without fruit in each ages. 2. The total dry matter per plant in bearing fruit (40.24g) had produced more dry matter than that of non-fruiting plant (38.13g) , but the root 4.y matter in fruiting plant (26.2g) had produced less dry matter than that of non-fruiting plant (27.1g) in 4 age. 3. The ginseng plant in bearing fruit did not influence the dry matter of stem and leaf. 4. The maximum RGR of root (17, June) was slower than that of fruit (4, June) .

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The Metabolism of (2-$^{14}C$) Mevalonic Acid on Photoperiodic Induction in Grafted Solanum Andigena

  • Bae, Moo;Mercer, E.I.
    • Nuclear Engineering and Technology
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    • 제2권2호
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    • pp.73-84
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    • 1970
  • Solanum andigena의 괴경생성형상과 스테톨의 관계를 구명하기 위하여 방사성 매바론산을 이용하여 대사를 연구하였다. 괴경생성에 단일광조성수도를 요하는 단일식물과 괴경을 생성치 않는 장일식물을 접목 시켰을때 장일식물이 괴경생성 홀몬을 받아 괴경을 생성하는 현상을 스테로이드와 결부시켜 구명할려고한것이다. 이 연구에서 각종 방사성 스테톨이 특수장치한 까스 크로마토 그라피로서 분리 측정되었다. 여기서 분리된 각종 스테톨이 직정 괴경생성홀몬이라는 근거는 찾을 수 없으며, 이들이 괴경의 포대성장에 필요한 인자로서 관여하고 있는 것으로 논의되었다.

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