• Title/Summary/Keyword: optimum condition

Search Result 4,679, Processing Time 0.032 seconds

Studies on the Pathogenic Alternaria Isolated from Seedlings of Pinus rigida Mill. - part II (리기다 소나무 유묘(幼苗)에 기생(寄生)하는 병원성(病原性) Alternaria균(菌)에 관(關)한 연구(硏究) - 제2보(第二報))

  • Yun, J.K.
    • Journal of Korean Society of Forest Science
    • /
    • v.6 no.1
    • /
    • pp.19-23
    • /
    • 1967
  • The fungus which belongs to Alternaria has been isolated from "damping-off" infected seedlings of pitch pine (Pinus rigida Mill.) in the nursery (seed bed) of Chung Puk College, Cheong-Ju. The author has carried out this study regarding to (1) the effects of H-ion concentration on the growth of fungus, (2) the effects of temperature and humidity on the conidia germination, (3) the effects of temperature and humidity on the conidia formation. The summary of obtained in this experiments is as follows: 1. The suitable H-ion concentration for growth of isolated fungus is in the range of PH 4.0-9.5, the most suitable of it is PH 6.5-8.0. 2. The germination of the conidia is suppressed at below $0^{\circ}C$ or at $40^{\circ}C$ and above, the range of optimum temperature for the germination is $5^{\circ}C-35^{\circ}C$, the percentage of germination is highest at $20^{\circ}C$. And under relative humidities of 10% or below, the germination is suppressed, favorable relative humidities $85%{\cdots}100%$. 3. The formation of the conidia is suppressed at below $10^{\circ}C$ or at $34^{\circ}C$ and above, the favorable condition of the condia formation is as follows; Temperature; $22^{\circ}C-28^{\circ}C$ Relative humidity:85%-100%.

  • PDF

Culture Conditions of Garlic Resistant Lactic Acid Bacteria for Feed Additives (사료첨가용 생균제 개발을 위한 마늘 내성 유산균의 배양 조건)

  • Kim, Yu-Jin;Jang, Seo-Jung;Park, Jung-Min;Kim, Chang-Uk;Park, Young-Seo
    • Food Engineering Progress
    • /
    • v.14 no.1
    • /
    • pp.65-74
    • /
    • 2010
  • Culture conditions of L. plantarum TJ-LP-002, the garlic resistant strain isolated from pakimchi (green onion kimchi), were investigated for the use of feed additives. Acetic acid, citric acid, lactic acid, and tartaric acid were detected in the culture supernatant, and especially the concentrations of lactic acid and acetic acid significantly increased during cultivation. The antimicrobial activity of L. plantarum TJ-LP-002 was not affected by proteases, calatase or cellulase, which showed that the antimicrobial activity might be due to the production of acids rather than proteinaceous antimicrobial substances. L. plantarum TJ-LP-002 was resistant to neomycin sulfate, spectinomycin dihydrochloride, and lincomycin hydrochloride, sensitive to streptomycin sulfate, and intermediate resistant to ampicillin trihydrate, chloramphenicol, erythromycin, tetracycline hydrochloride, and kanamycin sulfate. The optimum initial pH of medium, fermentation temperature and time for the cell growth and antibacterial activity were pH 7.0, 30${^{\circ}C}$ and 24hr, respectively. The optimal composition of culture medium for the cell growth and antimicrobial activity was 3%(w/v) glucose as a carbon source, 3%(w/v) yeast extract as a nitrogen source, and manganese sulfate and ammonium citrate as inorganic salts. The combinatorial supplementation of these inorganic salts, rather than sole addition as an inorganic salt, resulted in better antibacterial activity.

Rhizome Growth and Flowering of White Lotus (Nelumbo nucifera) at Muan Hoesan-Lake (무안 회산지(回山池) 백련꽃의 근경생장과 개화특성)

  • Im, Myung Hee;Park, Yong Seo;Hou, Won Noung;Park, Yun Jum;Heo, Buk Gu
    • FLOWER RESEARCH JOURNAL
    • /
    • v.17 no.1
    • /
    • pp.15-22
    • /
    • 2009
  • This study was conducted to examine characteristics of rhizome growth and flowering of white lotus (Nelumbo nucifera) plant in Muan Hoesan-lake for collecting the basic data on the cultivation and the flowering which is growing in Muan Hoesan-lake of Jeonnam province in Korea. We have planted from the seeds and the enlarged rhizomes of the white lotus which were planted in the plastic containers on April 20 and May 4, 2008, and cultivated under rain shelter condition. Rhizome growth pattern and the flowering characteristics of the white lotus were examined on September 4, 2008. Main rhizomes of the white lotus propagated by the seeds and the enlarged rhizomes were branched by 10% and 15%, respectively. Numbers of nodes in the bloomed and non-bloomed rhizomes of the white lotus were over 14 and below 11, respectively. Flower was not observed in the white lotus when propagated with seeds, however, flowers came out up to 80% by the enlarged rhizomes. First flowers were bloomed from the late July and to the early August, and the number of flowers were 4.0~4.4. The first flower stalks without branching of the main rhizome were emerged in 8.8th node, however, that with branching were 8.0th node. Time to flowering from the emergence of flower stalk on the above-ground parts were required 16 days. White flowers from the lotus were 15.3 cm in height and 28.2 cm in width, their longevity was 3.3 days and the averaged flower fresh weight was 29.2 g. The results conclude that optimum number of nodes on the main rhizomes for blooming the white lotus flowers should be over 8 nodes before the rhizome enlargement.

A Study on the Thermal Shock Resistance of Sintered Zirconia for Electron Beam Deposition (전자빔 증착을 위한 소결체 지르코니아의 열충격 저항성 연구)

  • Oh, Yoonsuk;Han, Yoonsoo;Chae, Jungmin;Kim, Seongwon;Lee, Sungmin;Kim, Hyungtae;Ahn, Jongkee;Kim, Taehyung;Kim, Donghoon
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.19 no.3
    • /
    • pp.83-88
    • /
    • 2015
  • Coating materials used in the electron beam (EB) deposition method, which is being studied as one of the fabrication methods of thermal barrier coating, are exposed to high power electron beam at focused area during the EB deposition. Therefore the coating source for EB process is needed to form as ingot with appropriate density and microstructure to sustain their shape and stable melts status during EB deposition. In this study, we tried to find the optimum powder condition for fabrication of ingot of 8 wt% yttria stabilized zirconia which can be used for EB irradiation. It seems that the ingot, which is fabricated through bi-modal type initial powder mixture which consists of tens of micro and nano size particles, was shown better performance than the ingot which is fabricated using monolithic nanoscale powder when exposed to high power EB.

Effect of Magnesium Oxide on Physical and Chemical Properties of FKM Elastomer (FKM Elastomer의 물리적 및 화학적 성질에 미치는 산화마그네슘의 영향)

  • Lee, Chang-Seop;Choi, Gi-Tae;Choi, Han-Hwal
    • Elastomers and Composites
    • /
    • v.38 no.1
    • /
    • pp.57-64
    • /
    • 2003
  • Metal oxide(MgO) was added to FKM rubber in order to develop automotive fuel hose which ran show elastic characteristics under extreme condition. Cure characteristics, physical properties, thermal resistance and fuel resistance of FKM compounded rubber with MgO were investigated. MgO was mixed to FKM rubber materials within the range of $0{\sim}20phr$. From the test results of rheological properties and Mooney viscosity, the $t_{s2}$, $T_{c90}$ values increased as the MgO contents increased in FKM rubber compounding. Hardness and 100% modulus of FKM compounded rubber slightly increased, but tensile strength and elongations at break slightly decreased. From the test results of thermal resistance of rubber specimens at 130, 150, and $170^{\circ}C$ for 70 hrs, the changing rate of physical properties was found to be relatively small. Fuel resistance tests were carried out for fuel A, B, C and D at $40^{\circ}C$ for 70hrs, and the results showed that the changing rate in physical properties was found to increase from Fuel A to D, Furthermore thermal properties of FKM compounded rubber containing MgO were also investigated by using TGA/DSC. The optimum mixing ratio of additive to FKM rubber to get the maximum effect on thermal resistance and fuel resistance, within the range of desirable specification for rubber material, was determined to be 6 phr for MgO.

Antimicrobial Activity of Polylysine Coated Film (Polylysine 코팅 필름의 항균활성)

  • Kim Seong-Cheol;Kim Jong-Chan;Park Kee-Jai;Choi Jong-Uck;Jeong Seung-Weon
    • Food Science and Preservation
    • /
    • v.12 no.4
    • /
    • pp.323-328
    • /
    • 2005
  • This study were investigated to analyzed an optimum preparation condition of coating film and its antimicrobial activity on pathogenic and deteriorative bacteria to obtain fundamental data for development of active packaging film using antimicrobial peptide, polysine. In the preparation conditions of coating film, antimicrobial activity was depending on the concentration of polylysine and polyamide respectively, and relatively high activity was obtained in the film prepared with more than $1.0\%$ (w/v) of polylysine, $40\%$ (w/v) polyamide, and more than $50\;{\mu}m$ of film thickness. Concentration of polylysine migrated from coated film to distilled water was reached at the maximum concentration, about 20 ppm after 3 days and in equilibrium after 7 days of soaking in sterilized water. An antimicrobial activity of coated film showed bactericidal effect of about $10^5\;CFU/mL$ comparing with the control against Bacillus cereus having $4.8{\times}10^5\;CFU/mL$ of initial viable cell numbers, and of about $10^2\;CFU/mL$ comparing with the control against Klebsiella pneumoniae having $6.8{\times}10^5\;CFU/mL$ of initial viable cell numbers. Consequently, it was revealed that polylysine coating film has a potential of applicable possibility as antimicrobial packaging film.

Biological Activity in Functional Cosmetic of Purple Sweet Potato Extracts (자색 고구마추출물의 기능성 화장품 활성)

  • Choi, Jae-Hong;Kim, Jin-Sung;Jo, Bun-Sung;Kim, Jeung-Hoan;Park, Hye-Jin;An, Bong-Jeun;Kim, Myung-Uk;Cho, Young-Je
    • Food Science and Preservation
    • /
    • v.18 no.3
    • /
    • pp.414-422
    • /
    • 2011
  • The optimum condition for phenolics contents extraction from purple sweet potato was 12 hrs. in 50% ethanol. The electron donating scavenging activities (DPPH), ABTS radical cation decolorization (ABTS) and antioxidant protection factor (PF) of Jami, Yeonjami and Shinjami were higher than general sweet potato, and thiobarbituric acid reaction substance (TBARs) was below 30%. The minimum inhibitory concentration (MIC) against Staphylococcus aureus and Escherichia coli on skin were each 5,000 and 2,500 ppm in all purple sweet potatoes, and MIC of Jami was the lowest as 2,500 ppm against Staphlococcus epidermidis. The whitening (tyrosinase inhibitory) activity of purple sweet potatoes was the highest as 62.5% and 48.7% in Jami water and ethanol extracts. The anti-inflammation (hyaluronidase inhibitory) activity of purple sweet potatoes was the highest as 25.3% and 94.4% in Jami water and ethanol extracts. The safety of cosmetic with Jam; extracts was assessed by various safety profiles. pH and viscosity change of essence for 90 days was not detected. Cosmetic was stable to temperature and light for 90 days. The result to measure changes of skin color and pore size of the skin was that an aged skin was more effective than young skin.

Effect of shelf-life extension of birch sap using high pressure processing (초고압 기술이 자작나무 수액의 저장성 향상에 미치는 영향)

  • Choi, Kyung Hwa;Kim, Sun Im;lee, Dong Uk;Jeon, Jung Tae
    • Food Science and Preservation
    • /
    • v.24 no.3
    • /
    • pp.343-350
    • /
    • 2017
  • Effects of high pressure processing on physicochemical and microorganisms properties in birch sap were investigated using variable high pressure processing conditions. The viable cell counts of untreated birch sap was 4.0 log CFU, whereas high pressure processed sap were not detected. In birch sap was treated with 450 to 550 MPa, microorganisms were not detected during storage period, and physicochemical properties as well as color were slightly changed. The more processing time and pressure, its quality variations were more stable and then its optimum processing condition was determined with 120 sec at 550 MPa. The microorganisms and physicochemical properties of treated birch sap were investigated during storage at $5^{\circ}C$ and $10^{\circ}C$ for 45 and 28 days. Changes of physicochemical properties of treated birch sap were smaller than those of the untreated, but viable cell count were not detected during storage period. As for pH, $^{\circ}Brix$, and turbidity result of birch sap, quality shelf life of control and treatment were 4 and 24 days, respectively. Especially, ${\Delta}E$ value of instrumental color was untreated birch sap 4 days similar with the high pressure processed it for 28 days. These results indicated that the high pressure processing can be used as an effective method to improve the shelf life of birch sap.

The Effect of Irrigation Control and the Application of Soil Ameliorators on Rice Yield by the Irrigation of Livestock Waste Water (수도(水稻)의 축산폐수피해(畜産廢水被害)에 대(對)한 물관리(管理) 및 개량제(改良劑) 시용효과(施用效果))

  • Lee, Min-Hyo;Kim, Bok-Young;Kim, Kyu-Sik;Park, Young-Dae
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.20 no.2
    • /
    • pp.123-129
    • /
    • 1987
  • In order to find out more effective countermeasures against growth damage of paddy rice due to the irrigation of livestock waste water, pot experiments were carried out in 1985 and 1986. Experiment I conducted in 1985 was to find out the effects of irrigation control and application of ameliorators to paddy soil with irrigation of animal waste water. Experiment II conducted in 1986 was to find out the amounts of wollastonite to be applied. The results obtained were as follows. Experiment I ; Rice yields were higher in the treatment of continuously submersion until harvest than in that of intermittent irrigation. The yield was also increased with the application of soil ameliorators and it showed higher increase in the treatment of zeolite and wollastonite. Nitrogen contents in plant were increased with the nitrogen application and more amounts of irrigation of waste water, but they were considerably decreased with the application of soil ameliorators. Experiment II ; Rice yields were increased with the application of wollastonite and the optimum level of wollastonite for maximum yield in condition of 3.0 g/pot of nitrogen application was belived to be 60g/pot. The increment of yield by the application of wollastinte was though to be due to increase of No. of grains per panicle and ripening ratio. Steriled neck occurred by rice disease such as rice blast was increased with increasing the amounts of nitrogen application and nitrogen contained in irrigated waste water but that was remarkably decreased with the application of wollastonite.

  • PDF

Properties Change of Korean Traditional Animal Glue Depending on The Parts of Cattle Hide and Extraction Conditions (소가죽부위 및 추출조건에 따른 전통 아교 특성 변화)

  • Cho, Gyu Hyuk;Choi, Ji Sun;Park, Dea Woo;Lee, Han Hyoung;Chung, Yong Jea
    • Journal of Conservation Science
    • /
    • v.37 no.5
    • /
    • pp.557-566
    • /
    • 2021
  • We investigated the properties of Korean traditional animal glue which are associated with the use of different parts of cattle hide and extraction conditions. Both average molecular weight(Mw, Mz) and polydispersity (PDI) of the animal glue increased with extraction time, whereas only PDI decreased after 48h. There were no differences in the average molecular weight and PDI for the different cattle hide parts used, although a individual difference was observed with regard to total molecular weight. Differences in extracts over time were compared by investigating the amide regions representing the gelatien component of the animal glue. The triple helix structure of the belly skin deteriorated in a manner proportional to the extraction time, and differences were observed for each cattle hide part. The yellowness increased with the extraction time; however, the viscosity was not proportional to the average change in molecular weight. This study has some limitations because of difficulties in the quality control of cases where small amounts of glue were extracted as small differences might impact the overall results considerably. Further research exploring various extraction conditions is required to ensure the prodiction of traditional animal glue with optimum qualities.