• 한국식품영양과학회지
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• 제41권9호
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• pp.1310-1314
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• 2012

본 실험은 제초제 내성을 가지는 CP4EPSPS를 도입시킨 유전자재조합 콩을 이용하여 인공위액의 비율에 따른 도입 단백질의 소화특성을 평가하고, 열처리가 유전자재조합 콩의 도입단백질의 소화성에 미치는 영향을 살펴보았다. 유전자재조합 콩과 펩신의 비율에 따른 도입단백질 CP4EPSPS의 소화성은 인공위액 즉 펩신의 양에 따라 차이를 나타내 유전자재조합 식품의 도입단백질에 대한 소화성 평가에서 펩신의 양이 중요한 요인이 됨을 알 수 있었다. 또한 유전자 재조합 콩에 대한 예열처리가 도입단백질 CP4EPSPS의 펩신에 대한 내성을 많이 감소시켜 소화성을 높이는 것으로 나타났다. 따라서 앞으로 유전자재조합식품의 안전성을 평가하는 in vitro 소화평가 시험에서 생리학적 측면에 근거한 인공위액의 비율을 반영함으로써 보다 정확한 도입단백질의 소화성에 대한 평가가 필요하리라 사료되며, 또한 콩의 주요 섭취방법인 열처리에 따른 도입단백질의 소화특성을 평가함으로써 유전자재조합 콩의 안전성에 대한 신뢰도 제고를 위한 기초자료가 될 것으로 기대된다.

• Journal of Microbiology and Biotechnology
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• 제29권2호
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• pp.200-208
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• 2019

Probiotics show low cell viability after oral administration because they have difficulty surviving in the stomach due to low pH and enzymes. For the oral delivery of probiotics, developing a formula that protects the probiotic bacteria from gastric acidity while providing living cells is mandatory. In this study, we developed tablets using a new pH-sensitive phthalyl inulin (PI) to protect probiotics from gastric conditions and investigated the effects of different compression forces on cell survival. We made three different tablets under different compression forces and measured survivability, disintegration time, and kinetics in simulated gastric-intestinal fluid. During tableting, there were no significant differences in probiotic viability among the different compression forces although disintegration time was affected by the compression force. A higher compression force resulted in higher viability in simulated gastric fluid. The swelling degree of the PI tablets in simulated intestinal fluid was higher than that of the tablets in simulated gastric fluid due to the pH sensitivity of the PI. The probiotic viability formulated in the tablets was also higher in acidic gastric conditions than that for probiotics in solution. Rapid release of the probiotics from the tablet occurred in the simulated intestinal fluid due to the pH sensitivity. After 6 months of refrigeration, the viability of the PI probiotics was kept. Overall, this is the first study to show the pH-sensitive properties of PI and one that may be useful for oral delivery of the probiotics.

• Mycobiology
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• 제39권1호
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• pp.67-69
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• 2011

A cell-free extract of Saccharomyces cerevisiae containing the angiotensin I-converting enzyme (ACE) inhibitory peptide was treated in a successive simulated gastric-intestinal bioreactor (step 1: amylase digestion, step 2: gastric fluid digestion, step 3: intestinal fluid digestion) to illustrate the absorption pattern of antihypertensive ACE inhibitory peptide, and the ACE inhibitory activities of each step were determined. Total ACE inhibitory activities of step 1, step 2, and step 3 were 55.96%, 80.09%, and 76.77%, respectively. The peptide sequence of each steps was analyzed by MS/MS spectrophotometry. Eleven kinds of representative peptide sequences were conserved in each step, and representative new peptides including RLPTESVPEPK were identified in step 3.

• 미생물학회지
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• 제36권2호
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• pp.161-165
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• 2000

국내 시판 19종의 드링크 및 18종의 액상 요구르트 제품에 함유된 2종의 유산균인 Lactobacilli 및 Bifidobacteria의 내산성을 인공위액(pH 1.5) 조건에서 비교 고찰되었다. 드링크 및 액상 요구르트 제품중 초기 Lactobacilli의 생존율은 각각 $10^8~10^{10}$ cfu/ml 및 $10^6~10^{10}$cfu/ml 범위 내에 있었다. 한편 드링크 요구르트 중 초기 Bifidobacteria의 생존율 $10^8~10^{10}$cfu/ml 이었다. 요구르트 제품중 Lactobacilli 및 Bifidobacteria의 생존율은 인공위액에 노출 시간이 증가함에 따라 점차 감소하는 경향을 나타내었으며 120분 노출시에 제품들간에 큰 차이를 나타내었다. (<$10^3~10^6$cfu/ml),캡슐을 함유한 요구르트 제품의 경우, 캡슐을 제외한 Mix는 인공위액에 30분에서 120분 노출시에 약$10^5$cfu/ml이상의 생존율을 나타내었으며 타사 제품과 유사한 거동을 보였다. 그러나 Bifidobacteria를 함유한 캡슐요구르트 제품의 경우 인공위액에 약 120문 노출시켰으때 타사 제품보다 생존율이 약10~737배 이상 증가하였다. 즉 Bifidobacteria의 내산성은 코팅물질을 사용한 캡슐로 봉입하였을 때 증가됨을 알 수 있었다.

• Journal of Pharmaceutical Investigation
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• 제21권2호
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• pp.85-90
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• 1991

Prodrugs of flurbiprofen, 1,2-ethanediolester(FE) and 1,4-butanediolester(FB) were prepared and their biopharmaceutical studies were performed. The prodrugs showed high stability in simulated gastric fluid, simulated intestinal fluid and pancreatin-saturated solution. Pharmacokinetic parameters of the prodrugs were similar to those of their parent drug. However they showed less acute toxicity and gastric irritation and higher anti-inflammatory and analgesic effects.

• 약학회지
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• 제33권5호
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• pp.312-318
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• 1989

Microcapsule of Propranolol HCl with Cellulose Acetate Phthalate (CAP) by coacervation-phase separation method was studied. Encapsulation was carried out in the CAP-liquid paraffin-acetone ethanol solvent system. The optimum weight ratio for microencapsulation in the CAP-liquid paraffin-solvent system was 1.32:89.18:9.50 or 1.65:89.42:8.93. The wall thickness of microcapsules increased according to increasing of CAP concentration, but dissolution rate decreased. The dissolution of propranolol-HCl in simulated gastric and intestinal fluid test solution was completed within 3 min., but T50% of propranolol HCl from 10.0% CAP-microcapsules were 390 min. and 210 min. respectively. The released amount from 12.5% CAP-microcapsules was 41.8% within 720 min. in simulatd gastric fluid test solution and T50% of those in simulated intestinal fluid test solution was 250 min.

• Journal of Pharmaceutical Investigation
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• 제33권3호
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• pp.179-185
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• 2003

Melatonin (MT) is an indole amide pineal hormone. It has not only very short half-life but also pH-sensitive property. The sustained release dosage form which delivers MT in a circadian fashion over 8 h is clinical value. The purpose of this study is to prepare sugar beads using multiple coating methods and enteric-coated in a sustained release to evaluate in vitro release characteristics in simulated gastric and intestinal fluids. The $Eudragit^{\circledR}$ as a polymer, sustained release membrane, and triethylcitrate (TEC) as a plasticzer were used. Multi-coated melatonin delivery system was composed of sugar, various excipients, $Eudragit^{\circledR}$ and enteric materials (e.g. hydroxy propyl methyl cellulose phthalate, HPMCP), and prepared by fluid bed coater. The dissolution test was carried out using the basket method at a stirring speed of 100 rpm at $37^{\circ}C$ in simulated gastric (pH 1.2) and intestinal fluid (pH 7.4). The released amount of MT was determined by High performance liquid chromatography method. The morhologies of surface and cross section of multi-coated beads were observed by scanning electron microscope. Size of multi-coated sugar beads was ranged over $1000{\sim}1300\;{\mu}m$. The release rate of MT from coated beads was limited in simulated gastric fluid (pH 1.2), but it was sustained in intestinal fluid (pH 7.4) during $3{\sim}8$ hours. The MT beads may provide small-intestine-targeted device for oral delivery. Studies on animal and relative experiment are in process.

• 한국축산식품학회지
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• 제34권1호
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• pp.20-25
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• 2014

This study evaluated the effects of frankfurter fat content on Listeria monocytogenes resistance to heat stress and gastric fluid, and the Caco-2 cell invasion efficiency of the pathogen. A 10-strain mixture of L. monocytogenes was inoculated on frankfurters formulated with 10%, 20%, and 30% fat content (10%: F10, 20%: F20, 30%: F30) and stored at $10^{\circ}C$ for 30 d. The samples were analyzed for L. monocytogenes resistance to heat stress and a simulated gastric fluid challenge. The total bacteria and L. monocytogenes survival rates were measured on tryptic soy agar plus 0.6% yeast extract and Palcam agar, respectively. L. monocytogenes colonies inoculated on F10, F20, and F30 samples were used for a Caco-2 cell invasion assay. In general, no obvious differences were observed between the survival rates of total bacteria and L. monocytogenes grown on different fat contents under heat stress and gastric fluid challenge. However, L. monocytogenes obtained from the F30 samples had a significantly higher Caco-2 cell invasion efficiency than those in the F10 and F20 samples (p<0.05). These results indicate that although high fat content in food may not be related to L. monocytogenes resistance to heat stress and gastric fluid, it may increase the Caco-2 cell invasion efficiency of the pathogen.

• Archives of Pharmacal Research
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• 제14권1호
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• pp.48-51
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• 1991

Amides from amino acid ester and nalidixic acid were synthesized. The solubility characteristics and partition coefficient of the compounds were studied. The hydrolysis of the compounds was studied in the simulated gastric fluid and simulated intestinal fluid. Some compounds showed better antibacterial activity than nalidixic acid.

• Asian-Australasian Journal of Animal Sciences
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• 제29권10호
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• pp.1490-1499
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• 2016

In this study, 69 lactobacilli isolated from Tibetan Qula, a raw yak milk cheese, were screened for their potential use as probiotics. The isolates were tested in terms of: Their ability to survive at pH 2.0, pH 3.0, and in the presence of 0.3% bile salts; tolerance of simulated gastric and intestinal juices; antimicrobial activity; sensitivity against 11 specific antibiotics; and their cell surface hydrophobicity. The results show that out of the 69 strains, 29 strains (42%) had survival rates above 90% after 2 h of incubation at pH values of 2.0 or 3.0. Of these 29 strains, 21 strains showed a tolerance for 0.3% bile salt. Incubation of these 21 isolates in simulated gastrointestinal fluid for 3 h revealed survival rates above 90%; the survival rate for 20 of these isolates remained above 90% after 4 h of incubation in simulated intestinal fluid. The viable counts of bacteria after incubation in simulated gastric fluid for 3 h and simulated intestinal fluid for 4 h were both significantly different compared with the counts at 0 h (p<0.001). Further screening performed on the above 20 isolates indicated that all 20 lactobacilli strains exhibited inhibitory activity against Micrococcus luteus ATCC 4698, Bacillus subtilis ATCC 6633, Listeria monocytogenes ATCC 19115, and Salmonella enterica ATCC 43971. Moreover, all of the strains were resistant to vancomycin and streptomycin. Of the 20 strains, three were resistant to all 11 elected antibiotics (ciprofloxacin, erythromycin, tetracycline, penicillin G, ampicillin, streptomycin, polymyxin B, vancomycin, chloramphenicol, rifampicin, and gentamicin) in this study, and five were sensitive to more than half of the antibiotics. Additionally, the cell surface hydrophobicity of seven of the 20 lactobacilli strains was above 70%, including strains Lactobacillus casei 1,133 (92%), Lactobacillus plantarum 1086-1 (82%), Lactobacillus casei 1089 (81%), Lactobacillus casei 1138 (79%), Lactobacillus buchneri 1059 (78%), Lactobacillus plantarum 1141 (75%), and Lactobacillus plantarum 1197 (71%). Together, these results suggest that these seven strains are good probiotic candidates, and that tolerance against bile acid, simulated gastric and intestinal juices, antimicrobial activity, antibiotic resistance, and cell surface hydrophobicity could be adopted for preliminary screening of potentially probiotic lactobacilli.