• 한국미생물·생명공학회지
• /
• 제29권3호
• /
• pp.142-148
• /
• 2001

경주 인근 지역의 토양으로부터 식물병원성 진균 Fusarium oxysprum과 phytophthora capsici를 동시에 길항할수있는 항진균성 항생물질 생산성 생물방제균을 분리하고, 성분을 함유한 병원진균의 세포벽을 분해하는 chitinase 생산성이 우수한 균주를 분리하고자 하였다. 분리된 생물방제균의 형태학적, 생화학적 및 배양학적으로 동정하여 잠정적으로 Bacillus amyloliquefaciens 7079로 동정하였다. 이 생물방제균이 생산하는 chitinase 생산의 최적 조건을 검토하여 본 결과 Chitin-yeast extract 배지(0.7% $K_2$$HPO_4$ 0.2% $KH_2$$PO_4$ 0.1%($NH_4$)$_2$$SO_4$ 0.05% sodium citrate 0.01% MgSO$_4$$7H_2$O 0.1% yeast extract, 0.1% coloida chitin)에서 pH는 7.0 배양온도는 3$0^{\circ}C$였고 배양한 후 3일 이 되었을 때 가장 많은 chitinase를 생산하였다. 또한 0.1% colloida chitin을 탄소원으로 하여 배양하였을 때 chitinase 생산성이 가장 좋았으며 0.15% proteose peptone NO .3 또는 0.1% tryptone 을 질소원으로 하여 배양하였을 때 효소 생산이 높게 나타났다. 선발된 생물방제균의 고추를 기주식물로한 in vivo pot 시험 결과 고추역병균 Phytophthora capsici에 좋은 길항력을 확인할 수 있었다.

• 한국식품과학회지
• /
• 제23권2호
• /
• pp.123-128
• /
• 1991

김치의 저장성을 향상시키고저 김치발효 중 첨가한 염혼합물이 김치액의 고형분 함량, 점도, 텍스쳐 및 관능적 특성에 어떠한 영향을 미치는지 검토하였다. 염혼합물은 인산나트륨, Ca-EDTA, $NaNO_2$, 구연산염들을 두 가지로 배합한 것이었으며 이들의 첨가농도는 $0.001{\sim}0.01\;M$ 범위였다. 그 결과 김치액의 점도는 저온에서 발효시킨 경우가 염혼합물을 첨가한 김치가 약간 더 높은 비교점도를 보여주었다. 배추의 견고성은 염첨가시 약간씩 계속 증가하는 경향을 보였으나 대조구는 pH 4.0 근처까지 증가하다가 감소하였다. 김치액의 고형분 농도의 변화는 대조구에서 초기에 증가하였다가 그 후 약간씩 감소하였으나 염첨가구는 계속 감소함을 보여주었다. 한편, 관능적 특성은 염혼합물 첨가구가 같은 pH범위($4.0{\sim}4.2$)에서 대조구보다 상큼한 맛과 신맛이 낮았으며 견고성과 질김성이 높았고 군덕내는 전반적으로 낮아 인산염 등 염혼합물의 첨가는 김치발효를 억제할 수 있었을 뿐만 아니라 김치의 관능적 성질에 좋은 영향을 주고 있음을 보여주었다.

• 한국미생물·생명공학회지
• /
• 제31권4호
• /
• pp.368-376
• /
• 2003

AA를 AA-2G로 전환하는 CGTase를 고정화하여 AA-2G 대량 생산의 가능성을 고찰한 결과, CNBr-sepharose 4B가 가장 효과적인 담체로 판명되었고, CGTase의 고정화 최적 조건과 고정화 CGTase에 의한 AA-2G 생산의 최적조건 및 재사용성을 검토하였다. 최적 고정화 조건은 효소량 24,000 units/g resin으로 9시간 반응하여 약 18,000 units/g resin의 최고 고정화율을 얻을 수 있으며, pH 5.0(50 mM sodium citrate buffer)용액에 12% AA-Na와 8% soluble starch를 기질로 하여 800 units/ml의 고정화 CGTase를 첨가한 후 $37^{\circ}C$에서 100 rpm으로 교반하면서 25시간 반응하여 약 18 mM의 AA-2G 최고량을 얻을 수 있었다. 또한 0.015 mM의 $CaCl_2$를 첨가하여 고정화 CGTase의 재사용성을 관찰한 결과, 5회까지 50% 이상의 AA-2G 생산율로서 그 가능성을 입증할 수 있었다. 그리고 효소의 재사용성이란 측면에서, 본 고정화의 다른 한 방법인 ultrafiltration(한외 여과)에 의해서는 Millipore사의 YM 10 membrane을 이용하여 먼저 단백질량과 효소 활성 변화를 측정하여 그 가능성을 확보할 수 있었으며, 기질 20 ml을 사용하여 AA-2G를 생성시킨 후, 한외여과에 의해 효소만을 회수하여 연속 반응해 본 결과 8회까지 50%의 생성률을 유지하였다. 따라서 한외 여과는 CNBr-sepharose 4B와 함께 효율적인 고정화의 한 방법으로 판명되었으며, 앞으로 이들 고정화 효소를 이용한 연속 반응 시스템의 구축이 뒤따라야 할 것이다.

• 한국환경농학회지
• /
• 제37권4호
• /
• pp.283-290
• /
• 2018

본 연구는 LC-MS/MS법을 적용하여 농산물에 함유된 pyridine계통의 제초제 Clopyralid의 잔류분석법을 확립하였다. 대표적인 농산물로는 귤, 고추, 대두, 감자 및 현미를 선정하였고 acetonitrile에 의해 추출된 성분을 QuEChERS법을 변경하여 정제법으로 사용하고 LC-MS/MS를 사용하여 분석법을 확립하였다. Clopyralid의 정량적 분석을 위한 최적 분석 조건을 확립하였으며, 검출한계는 0.001 mg/kg, 정량 한계(LOQ)는 0.01 mg/kg이었다. 각 대표 농산물에 대한 정량한계, 정량한계의 10배, 50배 수준에서 회수율을 검토한 결과 모든 처리 농도에서 81.7~105.8 %수준을 나타내었으며, 모든 수준에서 20 % 미만의 분석오차를 나타내어 잔류분석기준을 만족하였다. 본 연구에서 확립된 Clopyralid분석법은 검출한계, 회수율 및 분석오차에서 국제적 분석기준을 만족하는 분석법으로 농산물에 따라 정량분석법으로 사용 가능할 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제16권2호
• /
• pp.165-171
• /
• 2003

Sixty semen ejaculates collected at weekly interval from four Murrah Buffalo bulls over a period of seven months (Nov.1999 to May 2000) were used in the present study. Three buffer medium (sodium citrate, TES and Tris) were used for soaking of sephadex. Three grades of sephadex (G-15,G-100, and G-200) were used for preparation of columns. Columns of three different height (one, two and three cm) were used for separation of semen. Twenty semen ejaculates were used in each project. In the first experiment each semen ejaculates was divided into four parts. One part was kept as control and other three parts were passed thought one cm column of sephadex G-15 prepared in three different buffers. There was significant (p<0.05) increase in percent progressive sperm motility and percent live spermatozoa and decrease in percent abnormal spermatozoa and percent spermatozoa with damaged acrosome as well as sperm numbers after filtration through all the three columns. Sperm quality obtained in the filtrate of column prepared in Tris buffer was better in comparison to other two buffers. So the Tris buffer was used in the second trial. Twenty semen ejaculates were used in this experiment. Each semen ejaculate was divided into four parts. One part was kept as control (non-filtered) and other three parts were passed through columns of different grade of sephadex (G-15, G-100 and G-200). Progressive sperm motility and live sperm percentage improved significantly while decline in percent abnormal spermatozoa and percent spermatozoa with damaged acrosome and sperm concentration was observed after filtration through all the columns as compared to control (non-filtered) semen. Since post filtration quality of semen was better in the sephadex G-100 column, therefore it was selected for the next experiment. In third experiment, Tris buffer and sephadex G-100 were used for preparing columns of different height (one, two and three cm) and twenty semen ejaculates were filtered. The quality characteristics of semen (percent progressive sperm motility, percent live spermatozoa and sperm concentration) after filtration through one cm column were significantly (p<0.05) higher than after filtration through columns of two and three cm height. However non -significant (p>0.05) difference due to height of columns was observed for percent abnormal and percent damaged acrosome but 1 cm column comparatively gave better result than of 2 and 3 cm column height.

• Applied Microscopy
• /
• 제24권1호
• /
• pp.28-40
• /
• 1994

Xerostomia and xerophthalmia are delicate or serous side effects, occuring when the radiotherapy is administered to the head and neck cancer patient. It is known that the cause of the above side effect is radiosensitivity of serous cells. In this study, the ultrastructural features of the parotid glands of the X-irradiated rats were observed. Sprague-Dawley rats weighing 200-250g each were anesthetized with sodium thiopental, and placed on the Mitsubishi linear accelerator. Only the head and neck areas of animals were exposured at the distance of 80cm, within the area of $30X30cm$, in the depth of 1cm, with the speed of 200R/min. Total doses applied were 3,000R or 6,000R depending on the experimental groups. Animals were sacrificed on the 6th hour, 2nd day and 6th day after the irradiation. Parotid glands were fixed in the 2.5% glutaraldehyde-1.5% paraformaldehyde solution, and followed by refixation in the 1% osmium tetroxide solution. Dehydrated blocks were embedded in araldite mixture, and ultrathin sections were cut. Sections were contrasted with the solution of uranyl acetate and lead citrate, and observed with JEM 100 CX-II electron microscope. The results were as follows: 1. Normal parotid acinar cells are two types; the light and the dark acinar cells. The light acinar cell contains dense secretory granules, whereas dark acinar cells contains granules of medium density with some darker spots within them, or other cells contain granules of medium density with darker rims. 2. Six hours after the irradiation, many acinar cells were degenerated showing variable stages of cytolytic bodies, light bodies, or dense degenerations. Within the acinar cell, Golgi apparatus and granular endoplasmic reticula were most severely altered elements. Granules showed more contrasting densities and irregularities. 3. Two days after the irradiation, some cytolytic bodies, and focal lucent degeneration of cytoplasm, and fine granular alteration of cytoplasmic matrix were pronounced. But other elements including secretory granules are rather looked unlatered. 4. Six days after the irradiation, most severe alterations were seen. Many intracellular canaliculi (or secretion figures), quanta of cytoplasm containing secretion antecedants, severely irregular luminal border, and again contrasting density of secretory granules showing tigroid spots or dense rims were noted. And myoepithelial degenerations were observed not uncommonly. 5. Irregular densities of secretory granules were interpreted as abnormal components of protein or carbohydrate portion are synthesized or abnormally metabolized under severe X-irradiation. 6. Myoepithelial degeneration and related alteration of nerve endings, etc., were suggested as the other causes of xerostomia following X-irradiation. 7. It is requested that radiation doses should be arranged, considering in mind not only the sensitivity of acinar cells but also the myoepithelial and neural functions.

• BMB Reports
• /
• 제38권2호
• /
• pp.198-205
• /
• 2005

Resveratrol (RES) and genistein (GEN) are the dietary natural products known to possess chemopreventive property and also the ability to repair DNA damage induced by mutagens/carcinogens. It is believed that the therapeutic activity of these compounds could be primarily due to their interaction with nucleic acids but detailed reports are not available. We here explore the interaction of these drugs with nucleic acids considering DNA and RNA as a potential therapeutic target. The interaction of RES and GEN has been analysed in buffered solution with DNA [saline sodium citrate (SSC)] and RNA [tris ethylene diammine tetra acetic acid (TE)] using UV-absorption and Fourier transform infrared (FTIR) spectroscopy. The UV analysis revealed lesser binding affinity with nucleic acids at lower concentration of RES (P/D = 5.00 and 10.00), while at higher drug concentration (P/D = 0.75, 1.00 and 2.50) hyperchromic effect with shift in the ${\lambda}_{max}$ is noted for DNA and RNA. A major RES-nucleic acids complexes was observed through base pairs and phosphate backbone groups with K = $35.782\;M^{-1}$ and K = $34.25\;M^{-1}$ for DNA-RES and RNA-RES complexes respectively. At various concentrations of GEN (P/D = 0.25, 0.50, 0.75, 1.00 and 2.50) hyperchromicity with shift in the ${\lambda}_{max}$ from 260 $\rightarrow$ 263 om and 260 $\rightarrow$ 270 nm is observed for DNA-GEN and RNA-GEN complexes respectively. The binding constant (from UV analysis) for GEN-nucleic acids complexes could not be obtained due to GEN absorbance overlap with that of nucleic acids at 260 nm. Nevertheless a detailed analysis with regard to the interaction of these drugs (RES/GEN) with DNA and RNA could feasibly be understood by FTIR spectroscopy. The NH band of free DNA and RNA which appeared at $3550-3100\;cm^{-1}$ and $3650-2700\;cm^{-1}$ shifted to $3450-2950\;cm^{-1}$ and $3550-3000\;cm^{-1}$ in DNA-RES and RNA-RES complexes respectively. Similarly shifts corresponding to $3650-3100\;cm^{-1}$ and $3420-3000\;cm^{-1}$ have been observed in DNA-GEN and RNA-GEN complexes respectively. The observed reduction in NH band of free nucleic acids upon complexation of these drugs is an indication of the involvement of the hydroxyl (OH) and imino (NH) group during the interaction of the drugs and nucleic acids (DNA/RNA) through H-bonded formation. The interaction of RES and GEN with bases appears in the order of G $\geq$ T > C > A and A > C $\geq$ T > G. Further interaction of these natural compounds with DNA and RNA is also supported by changes in the vibrational frequency (shift/intensity) in symmetrical and asymmetrical stretching of aromatic rings of drugs in the complex spectra. No appreciable shift is observed in the DNA and RNA marker bands, indicating that the B-DNA form and A-family conformation of RNA are not altered during their interaction with RES and GEN.

• 자원리싸이클링
• /
• 제15권3호
• /
• pp.46-57
• /
• 2006

본 연구는 불순물을 포함하는 인산부생석고로부터 정제석고를 얻을 목적으로 수행되었다. 인산부생석고를 일정조건에서 탈수하고 수화시켜 석고성분만을 선택적으로 미립화 시킨 다음 325mesh로 습식사분하여 사하산물로 정제석고를 얻었다. 이 과정에서 석고의 회수율에 미치는 탈수온도, 탈수시간, 탈수율, aging시간, 수화농도, 수화온도, 초음파조사시간, 첨가제 등의 영향을 조사하였다. 실험결과, 인산부생석고를 $140^{\circ}C$에서 6시간 동안 건조하여 완전히 무수석고 상태가 되도록 탈수 한 다음, 슬러리 농도 $3{\sim}10%,\;20{\sim}30^{\circ}C$의 수화온도, 수화시간 2시간의 조건에서 수화하여 사분하면 석고회수율이 95% 이상이 됨을 알았다. 회수된 석고의 품위는 회수율이 높을수록 높아지는 경향을 보였으며 회수율이 90%이상 일 때 품위는 $94{\sim}96%$를 보였다. 이 밖에도 석고회수율을 높이기 위해서는 탈수된 석고가 공기와 접촉하는 시간이 16시간을 넘어서는 아니 되며, 구연산나트륨을 0.005M 정도 첨가하는 것과, 수화반응 초기에 $5{\sim}10$분 동안 초음파를 조사하는 것이 매우 유용한 수단임을 알았다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제22권8호
• /
• pp.1202-1208
• /
• 2009

Synbiotics is the term used for a mixture of probiotics (live microbial feed additives that beneficially affects the host animal) and prebiotics (non-digestible food ingredients that beneficially affect the organism). This study investigated the effect of probiotics from anaerobic microflora with prebiotics on growth performance, nutrient digestibility, noxious gas emission and fecal microbial population in weaning pigs. 150 pigs with an initial BW of 6.80${\pm}$0.32 kg (20 d of age) were randomly assigned to 5 dietary treatments as follows: i) US, basal diet+0.15% antibiotics (0.05% oxytetracycline 200 and 0.10% tiamulin 38 g), ii) BS, basal diet+0.2% synbiotics (probiotics from bacteria), iii) YS, basal diet+0.2% synbiotics (probiotics from yeast), iv) MS, basal diet+0.2% synbiotics (probiotics from mold), v) CS, basal diet+0.2% synbiotics (from compounds of bacteria, yeast and mold). The probiotics were contained in $10^{9}$ cfu/ml, $10^{5}$ cfu/ml and $10^{3}$ tfu/ml of bacteria, yeast and molds, respectively. The same prebiotics (mannan oligosaccharide, lactose, sodium acetate and ammonium citrate) was used for all the synbiotics. Pigs were housed individually for a 16-day experimental period. Growth performance showed no significant difference between antibiotic treatments and synbiotics-added treatments. The BS treatment showed higher (p<0.05) dry matter (DM) and nitrogen digestibility while ether extract and crude fiber digestibility were not affected by the dietary treatment. Also, the BS treatment decreased (p<0.05) fecal ammonia and amine gas emissions. Hydrogen sulfide concentration was also decreased (p<0.05) in BS, YS and MS treatments compared to other treatments. Moreover, all the synbioticsadded treatments increased fecal acetic acid concentration while the CS treatment had lower propionic acid concentration than the US treatment (p<0.05) gas emissions but decreased in fecal propionate gas emissions. Total fecal bacteria and Escherichia coli populations did not differ significantly among the treatments, while the Shigella counts were decreased (p<0.05) in synbiotics-included treatment. Fecal bacteria population was higher in the YS treatment than other treatments (p<0.05). The BS treatment had higher yeast concentration than YS, MS and CS treatments, while US treatment had higher mold concentrations than MS treatment (p<0.05). Therefore, the results of the present study suggest that synbiotics are as effective as antibiotics on growth performance, nutrient digestibility and fecal microflora composition in weaning pigs. Additionally, synbiotics from anaerobic microflora can decrease fecal noxious gas emission and synbiotics can substitute for antibiotics in weaning pigs.

• 대한화학회지
• /
• 제45권2호
• /
• pp.116-120
• /
• 2001

자화수의 물리화학적인 특성을 알아보기 위하여, 전해질의 용해 성질과 결정형성 양상을 관찰하고 석고의 수화반응을 조사하였다. 본 연구를 통하여 본 결과, 자화수는 일반 증류수에 비하여 NaCl 및 KCI 각각 영향을 주어, 이들 염류들의 용해속도와 결정화에 변화를 나타내었다. 또한 자화수는 일반 증류수에 비하여 석고의 수화반응을 촉진시키는 결과가 관찰되었다. 즉, 자화수의 물분자 배열이 NaCl 및 KCI과 상호 반응하여 NaCl인 경우에는 초기 용해속도를 감소키기고 결정화를 억제시키는 효과를 보였다. 그리고 석고의 경화에서는 자화수가 석고의 결정화를 증가시켰으며, 보다 치밀한 구조의 석고 결정화를 만들었다. 이러한 결과들은 모두, 일반 증류스에 비하여 자화수가 독특한 물분자 cluster 배열을 하고 있기 때문에, 각각의 염류 또한 석고와의 수화반응에 차이를 보인다고 생각된다.