An antimicrobial substance-producing microorganism was isolated from soil samples. Based of the taxonomic characteristics of its morphological, cultural, physiological properties and 16s rRNA sequence alignment, this microorganism was identified as Pseudomonas aeruginosa, and we named Pseudomonas aeruginosa EL-KM. The optimal culture condition for production of antimicrobial substance was 1% mannitol, 0.4% yeast extract, 0.5% Nacl, 0.2% K₂SO₄, 100μM MgSO₄.7H2O, 10μM CaCl2.$2H_2O$, 1μM $FeSO_4$.7H2O, 1μM MnSO4.$4-5H_2O$, initial pH 7 and 200 rpm at 30℃. The purification of the antimicrbial substance was performed by silica gel column chromatographys, and fraction with TLC $R_f$ 0.77 value represented good antimicrobial activity. The crude antimicrbial substance was stable within a pH range of 3-10 and temperature range of 4°C-121°C autoclaving. This crude antibacterial substance acted as bacteriolytic agent against Vibrio cholerae non-Ol ATCC 25872, and also exhibited excellent properties, when the substance was demonstrated against many other gram-positive, gram-negative bacteria, yeast and fungi.
Antibiotics supplementation in animal feeds results in bacterial resistance to the antibiotics and residue of the antibiotics in animal products, which can cause serious problems in human health. Therefore, the finding of new substances replacing antibiotics are needed. New substances are egg yolk antibody, probiotics, organic acid, mannanoligosaccharide(MOS), fructooligosaccharide(FOS), and chitosan etc. Egg yolk antibody is antibody to obtain from egg yolk of the chicken injected the specific antigen. Probiotics can prevent the problems of residue of the antibiotics and resistance to the antibiotics. Organic acids on preservation of colostrum inhibit the rottenness and increase the beneficial bacteria. MOS and FOS increase the beneficial bacteria, too. Chitosan is used the immune material to active the antibacteria.
경제적이면서 효과적인 항균성 필름의 생산방법으로서 corona 저려한 저밀도 폴리에틸렌 (LOPE) 필름에 천연항균성 물질을 코팅하는 방법을 개발하고, 이를 딸기의 포장에 적용하였다. 보다 안정한 항균제 코팅 필름의 생산을 위하여 결착제와 함께 코팅한 필름의 생산방법을 검토한 결과, polyamide수지용 과 항균생 물질을 함께 코팅함에 의하여 안정한 코팅을 행성할 수 있었다. 이의 항균성을 미생물 평판 배지 상에서 확인한 결과, 1% 자몽종자추
지난 반세기 동안내분비 장애물질의 제한없는 생산과 무분별한 소비, 방출, 폐기는 물, 흙, 공기 등 자연을 오염시켜 왔다. 그 결과 생태계의 야생동물이 오염되어, 생식과 발생의 이상이 일어나고, 멸종이 예견되기에 이르렀다. 또한 동물 자신은 물론, 후세대에 내분비계의 교란을 일으켜 정상적인 성생활, 발생과 생식의 기형, 정자수 감소 등의 불임유발, 성행동, 신경계와 면역계의 이상, 암까지 유발하는 것으로 알려지고 있다. 암이 개체의 사멸을 일으키는 반면
The influence of elevated CO2 and temperature on growth parameters, biomass production and its partitioning of rice (Oryza sativa L.cv. Chukwangbyeo) were investigated in the three experiments (1991-1993). Rice plants were grown from transplanting to harvest at either ambient(350ppm) or elevated CO2 concentrations (690 or 650ppm) in combination with either four or seven temperature regimes ranging form ambient temperature (AT) to AT plus 3℃.From transplanting to panicle initiation, crop growth rate (CGR) was enhanced by up to 27% with elevated CO2 , primarily due to an an increase in leaf area index. although net assimilatiion rate was also greater at elevated CO2. The effect of elevated CO2 varied with temperature. During the reproductive phase, CGR declined linearly with increased temperature, and was greater at elevated CO2 . Elevated CO2 increased final crop biomass and panicle weight 30% respectively at AT(27.6℃ : 1991) . However, there was no significant effect of elevated CO2 on panicle weight at AT plus 3℃, where severe spikelet sterility occurred. There was no significant effect of elevated CO2 on panicle weight at AT plus 3℃, where severe spikelet sterility occurred. There was also no effect of CO2 on biomass pratitioning into vegetative and reproductive organs (harvest index)) at AT, although higher temperature could affect that by inducing spikelet sterility. These results suggest that elevated CO2 could enhance rice producivity througth promoted growth and biomass production , but its positive effects may be less at higher temperatures.
Toxic Mastoparan B(MP-B) which is purified from the venom of the hornet Vespa basalis is a cationic amphiphilic tetradecapeptide. MP-B and its Ala-substituted analogues were synthesized by solid phase method and the toxic peptide-membrane interactions were examined by circular dichroism(CD) spectra, fluorescence spectra, and leakage abilities in phospholipid membranes. In the presence of phospholipid vesicles, synthetic MP-B and its analogues formed amphiphilic α-helical structures, but in the buffer solution, those exhibited random coil conformation as measured by CD. Fluorescence spectra of MP-13 and its analogues which indicated the binding affinity of peptide on phospholipid vesicles showed that the replacement of Lys at position 2 and 11 with Ala caused a remarkable effect in the blue shift and that at position 2, in the leakage ability of the peptide.
추파성정도가 높은 대맥품종 수원18호(IV)와 춘파성정도가 높은 강보리 (I)에 대하여 주간 20℃ , 야간 15℃ , 일장 15시간하에서 생육한 경우의 건물생산을 비교검토한 결과는 다음과 같다. 1) 상대생장율(RGR)은 생육이 진전됨에 따라 낮아지고 순동화율(NAR)은 수원18호에서는 상대생장율과 같은 경향을 보였으며 영양생장기간중에는 상대생장율과 순동화율간에는 깊은 관계가 있었다. 2) 생식생장기의 강보리에서는 엽신이외기관의 광합성생산이 중요한 역할을 하고 있었으며 이는 순동화율이나 광합성측정에서 표시할 수 있었다. 3) 생장관수 α 에 대하여 검토한 결과 강보리에서는 광합성산물이 경쪽으로 급격히 분배가 증대되는 시기가 되면 근쪽으로의 분배가 급격히 감소되었으나 영양생장을 계속하는 수원18호에서는 근으로의 배가 거의 일정한 경향이었다.