• Title/Summary/Keyword: mixed inhibition

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Effect of Nuclear Polyhedrosis Virus and NeemAzal-T/S on Spodoptera litura (Lepidoptera: Noctuidae) (담배거세미나방(Spodoptera litura)에 대한 핵다각체병바이러스와 NeemAzal-T/S의 혼합 살포효과)

  • 김선곤;김도익;박종대;박인진;임대준;김규진
    • Korean journal of applied entomology
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    • v.40 no.2
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    • pp.137-141
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    • 2001
  • This experiment was conducted to investigate the control effect of nuclear polyhedrosis virus and NeemAzal-T/S on Spodoptera litura larvae. In laboratory test, values of$ LT_{50}$ and $LT_{95}$ when treated with S. litura nuclear polyhedrosis virus (SINPV) $1$\times$10^{8}$ PIBs/ml plus NeemAzal-T/S 200 ppm were 1.94 and 8.33 days, respectively. Control effect of the combination of SINPV $1$\times$10^{8}$ plus NeemAzal-T/S 200 ppm was higher than the other concentrations. This mixed treatment could reduce LT$_{95}$ by 3 days. When SINPV alone was sprayed to the S. litura larvae reared on chinese cabbage seedling, the mortalities were 10.7~6.7% at 4 days after treatment. In combinations of SINPV plus NeemAzal-T/S at each level of concentration, the mortalities appeared faster and higher at 4 days after application than single treatment. Especially, the mortalities by combinations of SINPV $1$\times$10^{8}$ /PIBs/ml plus NeemAzal-T/S at 75~200 ppm were 100% at 9 days after treatment. The body weight of untreated larvae was increased 9.4-folds from 235 mg to 2194 mg after 7 days. However, the increasing levels of larval weight were 4.8- and 7.0-folds in the separate treatments of NeemAzal-T/S and SINPV, respectively. Whereas in the combinations of SINPV $10^{4~8}$ PIBs/ml plus NeemAzal-T/S 75~200 ppm, larval weight was increased 3.9 to 2.9-folds. These results showed that the mortality and inhibition of larval weight in the combination of SINPV and NeemAzal-T/S were highly enforced by synergistic effect.

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Growth and Flowering of Standard Chrysanthemums according to the Light Source and Light Quality in Night Break Treatment (광중단 처리에 있어서 광원 및 광질이 스탠다드 국화의 생육 및 개화에 미치는 영향)

  • Kwon, Young Soon;You, Bong Sik;Jung, Jae A;Park, Sang Kun;Shin, Hak Ki;Kil, Mi Jung
    • Journal of Bio-Environment Control
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    • v.23 no.4
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    • pp.263-268
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    • 2014
  • This research was performed to investigate the effect of light source and light quality in night break treatment on the growth and flowering of standard chrysanthemum. It was processed 4 hours (22:00-02:00) night break using LED 590, 610, 630, 660, 680nm and fluorescent lamp (mixed light of 480+540+610nm) in standard chrysanthemum 'Baekma' and 'Jinba' for 40 days from transplanting. The days to flower budding from short-day treatment of 'Baekma' were the longgest at fluorescent treatment (21.3 days) and were the shorttest at LED 590nm treatment (15.8 days) among all treatments. The days to flower budding from short-day treatment of 'Jinba' was longger with 18.0 days, 17.8 days, and 17.7 days at the fluorescent, LED 610nm, and 660nm treatments. And it was the shortest with 15.1 days in LED 590nm treatment. Similarly, the days to flowering from short-day treatment of 'Baekma' was the longgest with 56.9 days at fluorescent treatment, and was the shorttest in 51.6 days about LED 590 nm treatment. The days to flowering from short-day treatment of 'Jinba' was longer at fluorescent (56.0 days) and LED 660nm (56.7 days) treatments and was shortest at LED 590nm (52.9 days) among all treatments. Therefore, inhibition of flower bud initiation and flowering were the most effective under fluorescent treatment in case of 'Baekma', and fluorescent and LED 660nm treatments in case of 'Jinba'. The length and weight of cut flower of 'Baekma' and 'Jinba' were most excellent in fluorescent treatment in which the floral differentiation suppression effect was the best. Consequently, as to the growth and flowering of standard chrysanthemum, the treatment which was suitable as the light source and light quality for night break is regarded as the fluorescent lamp, and also under LED 660nm up to a certain level.

Effect of Aprotinin on Changes in Plasma Thromboxane $B_2$ and Endothelin-1 Concentratin after Extracorporeal Circulation (체외순환후 혈중 Thromboxane $B_2$와 Endothelin-1 농도 변화에 미치는 Aprotinin의 효과)

  • Lim, Cheong;Yun, Tae-jin;Kim, Yeon-seung;Kim, Seung-hoo;Lee, Jae-dam;Rho, Joon-Ryang;Song, Meong-Gun
    • Journal of Chest Surgery
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    • v.33 no.3
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    • pp.221-229
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    • 2000
  • Background: Thromboxane A2 and endothelin-1 are the potent vasoconstrictors affecting pulmonary pathophysiology in response to whole body inflammatin following CPB. Aprotinin, as an antiiflammatory agent, may decrease the release of such vasoactive substance from pulmonary tissues, preventing pulmonary hypertension after cardiopulmonary bypass. Material and Method: Ten mongrel dogs(Bwt. ac. 20kg) were subjected to cardioupulmonary bypass for 2 hours and postbypass pulmonary vascular resistance(0, 1, 2, 3 hours) were compared with prebypass level. The dogs were divided into 2 groups; control group(n-5) and aprotinin group(n=5). In the aprotinin group, aprotinin was administered as follows; 50,000 KIU/kg mixed in pump priming solution, 50,000 KIU/kg prebypass intravenous infusion over 30 minutes, 10,000 KIU/kg/hour postbypass continuous infusion. Prebypass and postbypass 0, 1, 2, 3 hour pulmonary vascular resistance were measured. At prebypass and postbypass 0, 90, 180 minutes, blood samples were obtained from pulmonary arterial and left atrial catherers for the assay of plasma thromboxane B2 a stable metabolite of thromboxane A2, and endothelin-1 concentrations. Result: The ratios of pustbypass over prebypass pulmonary vascular at postbypass 0, 1, 2, 3 hours were 1.28$\pm$0.20, 1.82$\pm$0.23, 1.90$\pm$0.19, 2.14$\pm$0.18 in control group, 1.58$\pm$0.18, 1.73$\pm$0.01, 1.66$\pm$0.10, 1.50$\pm$0.08 in aprotinin group ; the ratios gradually increased in control group while decreased or fluctuated after postbypass 1 hour in aprotinin group. There was statistically significant difference between control group and aprotinin group at postbypass 3 hours(P=0.014). Pulmonary arterial plasma concentration of thromboxane B2(pg/ml) at prebypass, postbypass 0, 90, 180 minutes were 346.4$\pm$61.9, 529.3$\pm$197.6, 578.3$\pm$255.8, 493.3$\pm$171.3 in control group, 323.8$\pm$118.0, 422.6$\pm$75.6, 412.3$\pm$59.9, 394.5$\pm$154.0 in aprotinin group. Left atrial concentrations were 339.3$\pm$89.2, 667.0$\pm$65.7, 731.2$\pm$192.7, 607.5$\pm$165.9 in control group, 330.0$\pm$111.2, 468.4$\pm$190.3, 425.4$\pm$193.6, 4.7.3$\pm$142.8 in aprotinin group. These results showed decrement of pulmonary thromboxane A2 generation in aprotinin group. Pulmonary arterial concentrations of endothelin-1(fmol/ml) at the same time sequence were 7.84$\pm$0.31, 13.2$\pm$0.51, 15.0$\pm$1.22, 16.3$\pm$1.73 in control group, 7.76$\pm$0.12, 15.3$\pm$0.71, 22.6$\pm$6.62, 14.9$\pm$1.11 in aprotinin group. Left atrial concentrations were 7.61$\pm$17.2, 57.1$\pm$28.4, 18.9$\pm$18.2, 31.5$\pm$20.5 in control group, 5.61$\pm$7.61, 37.0$\pm$26.2, 28.6$\pm$21.7, 37.8$\pm$30.6 in aprotinin group. These results showed that aprotinin had no effect on plasma endothelin-1 concentration after cardiopulmonary bypass. Conclusion: Administration of aprotinin during cardiopulmonary bypass could attenuate the increase in pulmonary vascular resistance after bypass. Inhibition of pulmonary thromboxane A2 generation was thought to be one of the mechanism of this effect. Aprotinin had no effect on postbypass endothelin-1 concentration.

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Application of 'Sponge Model' with Disinfectants for the Inhibition of Listeria monocytogenes (Listeria monocytogenes의 증식억제를 위한 살균제 'Sponge model'의 응용)

  • LEE Myung-Suk
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.29 no.5
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    • pp.595-602
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    • 1996
  • The antimicrobial effects of two disinfectants commonly used in food industry on Listeria monocytogenes ATCC 15313 were studied. The two disinfectants tested were commercial benzalkonium chloride (BAC) and sodium hypochlorite (NaOCl). Their effects were studied on cells suspended in disinfectants (in vitro) and in the sponge model with the disinfectants (in vivo). When cells were exposed to $0\~0.1\%$ BAC and $0\~150\;ppm$ NaOCL for 20 minutes, BAC and NaOCl concentration more than $0.25\%$ and 100 ppm showed the antimicrobial effects respectively. This organism decreased rapidly during the first $0.5\~1$ minute followed by a slower decrease during the rest of the exposure time. Fifteen ml of cell solution $(about\;10^7\;CFU/ml\;in\;the\;TSB)$ was mixed with 15 ml of disinfectants in the sponge $(6.0{\times}4.0{\times}4.0cm)$, BAC and NaOCl concentration more than $0.1\%$ and 300 ppm showed the antimicrobial effects, and at $0.25\%$ and 800 ppm diminished in cell numbers 3-log cycles during the first 20 minutes. In the case of sponge model, 15 ml of cell solution and 15 ml of disinfectants $(0.25\%\;of\;BAC,\;800\;ppm\;of\;NaOCl)$ were suspended in the sponge during 20 minutes, washing with 200 ml of sterilized distilled water, and this sponge was transfered in the 100 ml TBS, and then incubated at various temperature. The cells were increased about 1-log cycle during 24 hrs at $5\~15^{\circ}C$. And the others temperature, the cells growth was in proporation to storage tepmerature and the cells were about $10^9\;CFU/ml$ after $1\~3$ days incubations.

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Phytotoxicity Inducing Factors and Its Safening Methods for Benzenesulfonylurea Compound KSC-13906 (Benzenesulfonylurea계 화합물(化合物) KSC-13906의 약해발생요인(藥害發生要因) 및 경감방법(輕減方法))

  • Hwang, I.T.;Choi, J.S.;Hong, K.S.;Yoo, J.H.;Kim, J.S.;Cho, K.Y.
    • Korean Journal of Weed Science
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    • v.18 no.3
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    • pp.225-236
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    • 1998
  • KSC-13906 [Erythro N-{(4,6-dimethoxypyrimidin-2-yl)aminocarbonyl} -2-(2-fluoro-1-hydroxy-n-propyl) benzenesulfonamide, US Patent 5,461,025] was investigated how can control phytotoxicity fluctuation and what a good method apply to new rice herbicide. The growth inhibition was observed when the rice plants was transplanted at a shallow depth(0 - 1cm) and leaching was low(0 - 1cm/ day) from the paddy soil. KSC-13906 appeared to move readily down into the paddy soil with water by 3cm depth in the soil column(${\phi}$ 10cm) filled with loamy sand soil under 3cm/day of leaching condition. Artificial control releasing pattern, designed as treated with KSC-13906 of 9 or 18g ai/ha either at a once or daily treated dividing volume of 1/20, 1/25 and 1/30 of the total volume, increased the safety of KSC-13906 to direct seeded and transplanted rice. The safety of KSC-13906 was also enhanced when KSC-13906 was mixed with dymron. For example, the mixture of KSC-13906 and dymron effectively reduced injury of direct seeded rice plants at 18 and 500g ai/ha, respectively, treated 7 days after transplanting. However, combination of KSC-13906 and several herbicides didn't show any synergistic effetct on herbicidal activity and safening effect on rice. However, the combination of KSC-13906+dymron (9~12+250~500g ai/ha) or KSC-13906+mefenacet+dymron(9+250+250g ai/ha) controlled almost all weeds in paddy field without causing any injury to rice and thus the combination would successfully be used as an oneshot herbicide in rice culture.

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Physicochemical and functional characteristics of fermented products by using Sigumjang, Cheonggukjang and oak mushroom (시금장, 청국장 및 표고버섯을 혼합 발효한 제품의 이화학 및 기능적 특성)

  • Hong, Gi-Hyeong;Kim, Soo-Jung;Kim, Eun-Joo;Kim, Hyeong-Soo;Hwang, Eun-Gyeong
    • Food Science and Preservation
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    • v.21 no.2
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    • pp.276-285
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    • 2014
  • The purpose of this study was to develop a new fermented product (named as Cheonggeumjang) using Sigumjang, Cheonggukjang and Oak mushroom. This study was conducted to evaluate the effects of Sigumjang, Cheonggukjang, and Cheonggeumjang, which were mixed in a different ratio as A (Sigumjang: Cheonggukjang = 1:2), B (Sigumjang: Cheonggukjang = 1:1) and C (Sigumjang: Cheonggukjang = 2 : 1). Then, the functions and physicochemical properties of products were investigated. We found that the crude protein content in Cheonggeumjang was higher than in Sigumjang whereas fat and calories content was less than that of Cheonggukjang. Free sugar content in Cheonggeumjang C 5.8681 g/100g was the highest. Moroever, Cheonggeumjang C and Sigumjang has an antioxidant activities. The electron donating capacity, SOD like activity and the inhibitory effect on xanthine oxidase of these two were significantly high than other group. Fat rancidity is promoted in the presence of metal ion, Cheonggeumjang group has higher inhibitory effect on $Fe^{2+}$ion than on $Cu^{2+}$ ion. The rancidity of fat is also increased by reactive oxygens species, Cheonggeumjang group inhibited $H_2O_2$ in higher extent than $KO_2$. Also, ${\alpha}$-glucosidase inhibition activity of Cheonggeumjang C in all of the concentrations (300 ppm, 500 ppm and 700 ppm) is higher than other groups. In sensory evaluation, Cheonggeumjang C groups is ranked significantly higher than the other groups while considering color, flavor, taste and the overall acceptability. Taken together, the results of this study suggest that Cheonggeumjang is best ingredient for increasing the consumer acceptability and functionality.

Surface Characteristics and Spontaneous Combustibility of Coal Treated with Non-polar Solvent under Room Temperature (상온에서의 용매 처리를 통한 저등급 석탄의 표면물성 및 자연발화 특성 변화)

  • Jo, Wan Taek;Choi, Ho Kyung;Kim, Sang Do;Yoo, Ji Ho;Chun, Dong Hyuk;Rhim, Young Joon;Lim, Jeong Hwan;Lee, Si Hyun
    • Korean Chemical Engineering Research
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    • v.51 no.5
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    • pp.609-614
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    • 2013
  • This study investigated the spontaneous combustion behavior of solvent-treated low rank coals. Indonesian lignite (a KBB and SM coal) and sub-bituminous (a Roto coal) were mixed with non-polar 1-methyl naphthalene (1MN) either by mechanical agitation or ultrasonication. The property change associated with 1MN treatment was then analyzed using proximate analysis, calorific value analysis, Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy and moisture re-adsorption test. Susceptibility to spontaneous combustion was evaluated using crossingpoint temperature (CPT) measurement along with gas analysis by GC. A FT-IR profile showed that oxygen functional groups and C-H bonding became weaker when treated by 1 MN. XPS results also indicated a decrease of the oxygen groups (C-O-, C=O and COO-). Increased hydrophobicity was found in the 1MN treated coals during moisture readsorption test. A CPT of the treated coals was ${\sim}20^{\circ}C$ higher than that of the corresponding raw coals and the ultrasonication was more effective way to enhance the stability against spontaneous combustion than the agitation. In the gas analysis less CO and $CO_2$ were emitted from 1MN treated coals, also indicating inhibition of pyrophoric behavior. The surface functional groups participating in the oxidation reaction seemed to be removed by the ultrasonication more effectively than by the simple mechanical agitation.

Brief Introduction of Research Progresses in Control and Biocontrol of Clubroot Disease in China

  • He, Yueqiu;Wu, Yixin;He, Pengfei;Li, Xinyu
    • 한국균학회소식:학술대회논문집
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    • 2015.05a
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    • pp.45-46
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    • 2015
  • Clubroot disease of crucifers has occurred since 1957. It has spread to the whole China, especially in the southwest and nourtheast where it causes 30-80% loss in some fields. The disease has being expanded in the recent years as seeds are imported and the floating seedling system practices. For its effective control, the Ministry of Agriculture of China set up a program in 2010 and a research team led by Dr. Yueqiu HE, Yunnan Agricultural University. The team includes 20 main reseachers of 11 universities and 5 institutions. After 5 years, the team has made a lot of progresses in disease occurrence regulation, resources collection, resistance identification and breeding, biological agent exploration, formulation, chemicals evaluation, and control strategy. About 1200 collections of local and commercial crucifers were identified in the field and by artificiall inoculation in the laboratories, 10 resistant cultivars were breeded including 7 Chinese cabbages and 3 cabbages. More than 800 antagostic strains were isolated including bacteria, stretomyces and fungi. Around 100 chemicals were evaluated in the field and greenhouse based on its control effect, among them, 6 showed high control effect, especially fluazinam and cyazofamid could control about 80% the disease. However, fluzinam has negative effect on soil microbes. Clubroot disease could not be controlled by bioagents and chemicals once when the pathogen Plasmodiophora brassicae infected its hosts and set up the parasitic relationship. We found the earlier the pathogent infected its host, the severer the disease was. Therefore, early control was the most effective. For Chinese cabbage, all controlling measures should be taken in the early 30 days because the new infection could not cause severe symptom after 30 days of seeding. For example, a biocontrol agent, Bacillus subtilis Strain XF-1 could control the disease 70%-85% averagely when it mixed with seedling substrate and was drenching 3 times after transplanting, i.e. immediately, 7 days, 14 days. XF-1 has been deeply researched in control mechanisms, its genome, and development and application of biocontrol formulate. It could produce antagonistic protein, enzyme, antibiotics and IAA, which promoted rhizogenesis and growth. Its The genome was sequenced by Illumina/Solexa Genome Analyzer to assembled into 20 scaffolds then the gaps between scaffolds were filled by long fragment PCR amplification to obtain complet genmone with 4,061,186 bp in size. The whole genome was found to have 43.8% GC, 108 tandem repeats with an average of 2.65 copies and 84 transposons. The CDSs were predicted as 3,853 in which 112 CDSs were predicted to secondary metabolite biosynthesis, transport and catabolism. Among those, five NRPS/PKS giant gene clusters being responsible for the biosynthesis of polyketide (pksABCDEFHJLMNRS in size 72.9 kb), surfactin(srfABCD, 26.148 kb, bacilysin(bacABCDE 5.903 kb), bacillibactin(dhbABCEF, 11.774 kb) and fengycin(ppsABCDE, 37.799 kb) have high homolgous to fuction confirmed biosynthesis gene in other strain. Moreover, there are many of key regulatory genes for secondary metabolites from XF-1, such as comABPQKX Z, degQ, sfp, yczE, degU, ycxABCD and ywfG. were also predicted. Therefore, XF-1 has potential of biosynthesis for secondary metabolites surfactin, fengycin, bacillibactin, bacilysin and Bacillaene. Thirty two compounds were detected from cell extracts of XF-1 by MALDI-TOF-MS, including one Macrolactin (m/z 441.06), two fusaricidin (m/z 850.493 and 968.515), one circulocin (m/z 852.509), nine surfactin (m/z 1044.656~1102.652), five iturin (m/z 1096.631~1150.57) and forty fengycin (m/z 1449.79~1543.805). The top three compositions types (contening 56.67% of total extract) are surfactin, iturin and fengycin, in which the most abundant is the surfactin type composition 30.37% of total extract and in second place is the fengycin with 23.28% content with rich diversity of chemical structure, and the smallest one is the iturin with 3.02% content. Moreover, the same main compositions were detected in Bacillus sp.355 which is also a good effects biocontol bacterial for controlling the clubroot of crucifer. Wherefore those compounds surfactin, iturin and fengycin maybe the main active compositions of XF-1 against P. brassicae. Twenty one fengycin type compounds were evaluate by LC-ESI-MS/MS with antifungal activities, including fengycin A $C_{16{\sim}C19}$, fengycin B $C_{14{\sim}C17}$, fengycin C $C_{15{\sim}C18}$, fengycin D $C_{15{\sim}C18}$ and fengycin S $C_{15{\sim}C18}$. Furthermore, one novel compound was identified as Dehydroxyfengycin $C_{17}$ according its MS, 1D and 2D NMR spectral data, which molecular weight is 1488.8480 Da and formula $C_{75}H_{116}N_{12}O_{19}$. The fengycin type compounds (FTCPs $250{\mu}g/mL$) were used to treat the resting spores of P. brassicae ($10^7/mL$) by detecting leakage of the cytoplasm components and cell destruction. After 12 h treatment, the absorbencies at 260 nm (A260) and at 280 nm (A280) increased gradually to approaching the maximum of absorbance, accompanying the collapse of P. brassicae resting spores, and nearly no complete cells were observed at 24 h treatment. The results suggested that the cells could be lyzed by the FTCPs of XF-1, and the diversity of FTCPs was mainly attributed to a mechanism of clubroot disease biocontrol. In the five selected medium MOLP, PSA, LB, Landy and LD, the most suitable for growth of strain medium is MOLP, and the least for strains longevity is the Landy sucrose medium. However, the lipopeptide highest yield is in Landy sucrose medium. The lipopeptides in five medium were analyzed with HPLC, and the results showed that lipopeptides component were same, while their contents from B. subtilis XF-1 fermented in five medium were different. We found that it is the lipopeptides content but ingredients of XF-1 could be impacted by medium and lacking of nutrition seems promoting lipopeptides secretion from XF-1. The volatile components with inhibition fungal Cylindrocarpon spp. activity which were collect in sealed vesel were detected with metheds of HS-SPME-GC-MS in eight biocontrol Bacillus species and four positive mutant strains of XF-1 mutagenized with chemical mutagens, respectively. They have same main volatile components including pyrazine, aldehydes, oxazolidinone and sulfide which are composed of 91.62% in XF-1, in which, the most abundant is the pyrazine type composition with 47.03%, and in second place is the aldehydes with 23.84%, and the third place is oxazolidinone with 15.68%, and the smallest ones is the sulfide with 5.07%.

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A Study on the Conversion to Feed Stuff from Cellulosic Biomass (섬유질자원(纖維質資源)의 사료(飼料) 전환(轉換))

  • Lee, Ke-Ho;Sung, Chang-Geun;Chung, Kyu-Ok
    • Applied Biological Chemistry
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    • v.27
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    • pp.29-46
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    • 1984
  • To utilize several species of hard wood as raw materials of feed products, fermentation characteristics of cellulosic substrates to single cell protein was investigated, and results were summarized as follows. Among the microorganisms investigated, Tricoderma viride was selected as one of the most cellulolytic. Mixed culture of fungi did not show a synergistic effect on cellulose degradation. When the fungi were cultured at $28^{\circ}C$ for 7 days in a medium containing wheat bran 25 g, cellulose 0.25 g, proteose peptone 0.025 g and tween 800.025 g, cellulotic activities on carboxy methyl cellulose and filter paper reached maximum at 12 hr. The alkali treatment resulted in increased degradation of substrate from 13 to 18% when treated with enzymes for 12h, and reducing sugar formation increased with decreased size of substrates. Glucose was a very good feedback inhibitor of the enzyme from T.viride than that of xylose. When the substrate was rehydrolyzed, hydrolysis rate was 31% to reducing sugars within 12 hr. Quantative anlysis with HPLC showed the ratio of glucose to xylose in sugar syrups as 1.77 to 1. For the purpose of producing cellulosic-single cell protein from the sawdust of mulberry tree, 15 strains of xylose-assimilating yeast were isolated from 42 samples of rotten woods and compost soils and examined for their ability to utilize xylose. Then three strains were selected by their strong xylose-assimilating activities. The cultivative condition, the growth characteristics, and protein and nucleic acid productivities of three strains were investigated. The results obtained were, 1. Wood hydrolysate of mulberry tree was assimilated by 5 strains of CHS-2, CHS-3, ST-40, CHS-12 and CHS-13. 2. The optimum initial pH and temperature for the growth of strain CHS-13 were 4.4 and $30^{\circ}C$. 3. The specific growth rate of strain CHS-13 was $0.23h^{-1}$ and generation time was 3.01 hrs at the optimum condition. 4. CHS-13 strain assimilated 81 % of sugar in wood hydrolysate. 5. CHS-13 strain was identified as Candida guilliermondii var. guilliermondii 6. When the CHS-13 strain was cultured in the wood hydrolysate containing yeast extract, L-protein content was increased with yeast extract concentration. 7. The L-protein and nucleic acid yields from wood hydrolysate were 0.73 mg/ml and $4.92{\times}10^{-2}\;mg/ml$ respectively. 8. An optimal nucleic acid content of CHS-13 strain was observed in the medium containing 0.2% of yeast extract.

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The effects of aqueous extracts of plant roots on germination of seeds and growth of seedings (식물근의 추출물질이 종자발아 및 유식물의 생장에 미치는 영향)

  • Chan-Ho Park
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.4 no.1
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    • pp.1-23
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    • 1968
  • This study aimed at contributing to the improvement of cropping systems after finding out the effects of excrements and components of crop root influence on other crops as well as themselves. The following forage crops suitable for our country were selected for the present study. Aqueous extracts of fresh roots, aqueous extracts of rotting roots and aqueous solutions of excrements of red clover, orchard grass and brome grass were studied for the effects influencing the germination and growth of seedlings of red clover, ladino clover, lespedeza, soybean, orchard grass, Italian ryegrass, brome grass, barley, wheat, sorghum, corn and Hog-millet. In view of the possibility that the organic acid might be closely related to the excrements and components of crop root connected with soil sickness, the acid components of three species of roots were analysed by paper chromatography and gas chromatography method. The following results were obtained: 1. Effects of Aqueous Extracts of Fresh Roots : Aqueous extracts of red clover: The extracts inhibited the growth of seedlings of the ladino clover and lespedeza and also inhibited the development of most crops except that of sorghum among the Graminaceae. Aqueous extracts of orchard grass: The extracts promoted the seedlings growth of red clover and soybean, while it inhibited the germination and growth of orchard grass. There were no noticeable effects influencing other crops while it inhibited the growth of barley and Hog-millet. Aqueous extracts of brome grass: There was no effect on Italian ryegrass but there was an inhibiting effect on the other crops. 2. Effects of Aqueous Extracts of Rotting Roots : Aqueous extracts of red clover: The extracts promoted the seedling growth of red clover. But it reflected the inhibiting effects on other crops except sorghum. Aqueous extracts of orchard grass: The extracts promoted the growth of red clover, ladino clover, soybean and sorghun, while it inhibited the germination and rooting of barley and Hog-millet. Aqueous extracts of brome grass: The extracts gave the promotive effects to the growth of red clover, soybean and sorghum, but caused inhibiting effects on orchard grass, brome grass, barley and Hog-millet. 3. Effects of Aqueous Solutions of Excrements : The aqueous solution of excrements of red clover reflected the inhibition effects to the growth of Graminaceae, while the aqueous solutions of excrements of orchard grass and Italian ryegrass caused the promotive effects on the growth of red clover. 4. Results of Organic Acid Analysis : The oxalic acid, citric acid, tartaric acid, malonic acid, malic acid and succinic acid were included in the roots of red clover as unvolatile organic acid, and in the orchard grass and brome grass there were included the oxalic acid, citric acid, tartaric acid and malic acid. And formic acid was confirmed in the red clover, orchard grass and brome grass as volatile organic acid. In consideration of the results mentioned in above the effects of excrements and components of roots found in this studies may be summarized as follows. 1) The red clover generally gave a disadvantageous effect on the Graminaceae. Such trend was considered chiefly caused by the presence of many organic acids, namely oxalic, citric, tartaric, malonic, malic, succinic and formic acid. 2) The orchard grass generally gave an advantageous effect on the Leguminosae. This may be due to a few kinds of organic acid contained in the root, namely oxalic, citric, tartaric, malic and formic acid. Furthermore a certain of promotive materials for growth was noted. 3) As long as the root of brome grass are not rotten, it gave a disadvantageous effect on the Leguminosae and Graminaceae. This may be due to the fact that several unidentified volatile organic acid were also included besides the confirmed organic acid, namely oxalic, citric, tartaric, malic and formic acid. 5. Effects of Components in Roots to the Soil Sickness : 1) It was considered that the cause of alleged red clover's soil sickness did not result from the toxic components of the roots. 2) It was recognized that the toxic components of roots might be the cause of soil sickness in case the orchard grass and brome grass were put into the long-term single cropping. 6. Effects of Rooted Components to the Companion Crops in the Cropping System : a) In case of aqueous extracts of fresh roots and aqueous excrements (Inter cropping and mixed cropping) : 1) Advantageous combinations : Orchard grass->Red clover, Soybean, Italian ryegrass->Red clover, 2) Disadvantageous combinations : Red clover->Ladino clover, Lespedeza, Orchard grass, Italian ryegrass, Fescue Ky-31, Brome grass, Barley, Wheat, Corn and Hog.millet, Orchard grass->Lespedeza, Orchard grass, Barley and Hog-millet, Brome grass->Red clover, Ladino clover, Lespedeza, Soybean, Orchard grass, Brome grass, Barley, Wheat, Sorghum, Corn and Hog-millet, 3) Harmless combinations : Red clover->Red clover, Soybean and Sorghum, Orchard grass->Ladino clover, Italian ryegrass, Brome grass, Wheat, Sorghum and Corn, Brome grass->Italian ryegrass, b) In case of aquecus extracts of rotting roots(After cropping) : 1) Advantageous combinations : Red clover->Red clover and Sorghum, Orchard grass->Red clover, Ladino clover, Soybean, Sorghum, and Corn, Brome grass->Red clover, Soybean and Sorghum, 2) Disadvantageous combinations : Red clover->Lespedeza, Orchard grass, Italian ryegrass, Brome grass, Barley, Wheat, and Hog-millet Orchard grass->Barley and Hog-millet, Brome grass->Orchard grass, Brome grass, Barley and Hog-millet, 3) Harmless combinations : Red clover->Ladino clover, Soybean and Corn, Orchard grass->Lespedeza, Orchard grass, Italian ryegrass, Brome grass and Wheat Brome gass->Ladino clover, Lespedeza, Italian ryegrass and Wheat.

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