• Journal of Microbiology and Biotechnology
• /
• v.19 no.1
• /
• pp.83-92
• /
• 2009

Individual immunochromatographic assays (ICG) for ochratoxin A (OTA) and zearalenone (ZEA) were optimized and used in the development of a one-step simultaneous immunochromatographic assay (OS-ICG) for the rapid multianalysis of two mycotoxins in corn samples. The nitrocellulose membrane of the OS-ICG was treated with OTA-bovine serum albumin (BSA), ZEA-ovalbumin (OVA), and anti-mouse IgG in the OTA test, ZEA test, and control zones, respectively. Monoclonal antibody-gold conjugates (OTA3 MAb-gold and ZEA2C5 MAb-gold) were sprayed onto the conjugate pad. The visual detection limits were 2.5 and 5 ng/ml for OTA and ZEA, respectively, and the results were obtained within 15 min after starting the analysis. An efficient, simple, and rapid extraction method using 30% MeOH/PBS was established and validated by analyzing the corn samples spiked with OTA/ZEA mixtures (0/0, 5/10, 10/20, and $20/30\;{\mu}g/kg$). The cut-off values of the OS-ICG for the spiked corn were 5 and $10\;{\mu}g/kg$ for OTA and ZEA, respectively. Natural corn samples were analyzed by OS-ICG, direct competitive enzyme-linked immunosorbent assay (DC-ELISA), and HPLC. Results of the OS-ICG were in good agreement with those obtained by DC-ELISA and HPLC. The developed OS-ICG offers a rapid, easy-to-use, and portable analytical system and can be used as a convenient qualitative tool for the on-site simultaneous determination of OTA and ZEA in cereals, food, and agricultural products in one analytical cycle.

• Journal of Microbiology and Biotechnology
• /
• v.26 no.12
• /
• pp.2051-2059
• /
• 2016

To date, there has been no employment of a magnetoelastic (ME) biosensor method to detect Salmonella enterica serovar Typhimurium in soil. The ME biosensor method needs to be investigated and modified for its successful performance. The filtration method, cation-exchange resin method, and combinations of both methods were employed for the extraction of S. Typhimurium from soil. The number of S. Typhimurium and the resonant frequency shift of the ME sensor were then compared using a brilliant green sulfa agar plate and an HP 8751A network analyzer. A blocking study was performed using bovine serum albumin (BSA), polyethylene glycol (PEG), and casein powder suspension. Finally, the modified ME biosensor method was performed to detect S. Typhimurium in soil. The number of S. Typhimurium was significantly decreased from 7.10 log CFU/soil to 4.45-4.72 log CFU/soil after introduction of the cation-exchange resin method. The greatest resonant frequency shift of the measurement sensor was found when employing centrifugation and filtration procedures. The resonant frequency shift of the PEG-blocked measurement sensor was $3,219{\pm}755Hz$, which was significantly greater than those of the BSA- and casein-blocked ME sensor. The optimum concentration of PEG was determined to be 1.0 mg/ml after considering the resonant shift and economic issue. Finally, the modified ME biosensor method was able to detect S. Typhimurium in soil in a dose-response manner. Although these modifications of the ME biosensor method sacrificed some advantages, such as cost, time effectiveness, and operator friendliness, this study demonstrated a novel approach of the ME biosensor method to detect S. Typhimurium in soil.

• Korean Journal of Food Science and Technology
• /
• v.19 no.2
• /
• pp.140-145
• /
• 1987

The partition coefficient of the proteins of known effective hydrophobicity was determined in a poly (ethylene glycol)-dextran aqueous two-phase system. The changes in the partition coefficient was also determined when a fraction of PEG-palmitate (PEG-P) was added to the system. The partition coefficient of the proteins increased as the concentrations of PEG and dextran increased at a constant phase volume ration irrespective of the effective hydrophobicity of the proteins. When small amounts of PEG-P were added to the PEG phase, the partition coefficients of BSA and ${\beta}-lactoglobulin$, which had relative hydrophobicity (RI) of 700 and 120, respectively, increased more than ten-fold, whereas ovalbumin whose RI was 5 showed little change. The drastic increases m the partition coefficient were observed by the addition of PEG-P in 2% level to the PEG system. Addition of PEG-P over 5% level resulted in a slight further increase in the partition coefficient of all proteins tested.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.19 no.6
• /
• pp.1615-1621
• /
• 2005

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are widely implicated in the aging process and age-related diseases. The present study was carried out to investigate scavenging activities of Junglans sinensis extract and its subfraction using fluorescent probes, DCF-DA, DAF-2 and DHR 123. Jungians sinensis was washed and crushed. The crushed Junglans sinensis was extracted 3times, each time with 3 volumes of methyl alcohol at $60^{\circ}C$ for 24 h. The extract was filtered and evaporated under a reduced pressure using a rotary evaporator to yield 16 g. Scavenging activities of $ONOO^-$ was measured by Kooy' method and ROS was measured by DCFDA assay. Junglans sinensis had the marked scavenging activites of $ONOO^-$, NO and $O_2^-$. Junglans sinensis scavenged $ONOO^-$ through electron donation and dose-dependently inhibited the nitration of bovine serum albumin by $ONOO^-$. Junglans sinensis also had ROS scavenging activity. Especially, ethylacetate fraction of Junglans sinensis showed the most effective scavenging activities for ROS and RNS. These results suggest that Junglans sinensis might be developed as an effective ROS and RNS scavenger Therefore, Junglans sinensis might be used as a preventive agent for the aging and relevant to aging of illness.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1995.04a
• /
• pp.125-125
• /
• 1995

Quinolone계 항균제인 rufloxacin의 전임상시험의 일환으로 항원성 유발여부를 평가하기 여부를 평가하기 위하여 아나필락시스 쇼크 반응시험, 수동 피부 아나필락시스 반응시험 및 간접 적혈구 응집 반응시험을 실시하여 다음과 같은 결과를 얻었다. 1. 기니픽을 이용한 아나필락시스 쇼크 반응시험에서 rufloxacin의 저용량투여군(1mg/body, 추정임상용량), 고용량투여군(5mg/body), 고용량혼합투여군(5mg/body mixed with Freunds' complete or incomplete adjuvant) 및 단백결합혼합투여군(rufloxacin-BSA, 1mg/body)에 있어서 아나필락시스 쇼크 반응이 관찰되지 않았다. 2. 마우스-랫드를 이용한 수동 피부 아나필락시스 반응시험에서 저용량투여군, 고용량투여군, 오용량혼합투여군 및 bovine serum albumin(BSA)과 결합시킨 단백결합혼합투여군 모두에서 음성의 반응을 나타내었다. 3. 간접 적혈구 응집 반응시험 결과 저용량투여군, 고용량투여군, 고용량혼합투여군 및 단백결합혼합투여군에서는 각군당 1-4마리에서 16-32배에서 양성반응을 나타내었다. 그러나 음성대조군에서도 10마리 중 4마리에서 16-32배에서 양성반응을 나타낸 것으로 미루어 약물투여군에서의 미약란 양성반응이 약물특이적 반응은 아닌 것으로 사료된다. 이상의 실험결과로 미루어 rufloxacin은 항체 생성능은 가지지 않는 것으로 사료된다. 이상의 실험결과를 종합하여 볼 때 ndloxacin은 전반적인 항원성 potential은 없는 것으로 사료되며 또한 생체내에서 체내 단백과 결합하여 hapten으로 작용할 가능성은 없는 것으로 사료된다.

• Food Science of Animal Resources
• /
• v.30 no.6
• /
• pp.923-929
• /
• 2010

Colostral whey prepared from colostrum (pooled from first six post-partum milkings) was heated for 10 min at $100^{\circ}C$ Heated colostral whey was incubated with 1% enzymes (protein equivalent basis) for 15, 30, 60, 90, and 120 min at $50^{\circ}C$. Papain, pepsin, trypsin, and alcalase produced different degrees of hydrolysis (DH), 10.66%, 12.42%, 10.83%, and 25.31%, respectively, at an incubation time of 120 min. The SDS-PAGE reveals that significant amounts of bovine serum albumin (BSA), ${\beta}$-lactoglobulin (${\beta}$-LG), and ${\alpha}$-lactalbumin (${\alpha}$-LA) survived papain digestion. In contrast, pepsin completely removed BSA but not ${\beta}$-LG present in heated colostral whey. Alcalase completely eliminated BSA, ${\beta}$-LG, and ${\alpha}$-LA. This differential hydrolysis was confirmed by reversed-phase HPLC analysis. Using ion-exchange chromatography, fraction-1 (F-1) was obtained from alcalase hydrolysate at a NaCl gradient concentration of 0.25 M. Reversed-phase HPLC chromatograms of alcalase F-1 showed numerous small peaks, which probably indicate that a variety of new peptides were produced. Iron content of alcalase F-1 was 28.94 ppm, which was the highest among all enzyme fractions, whereas iron content of colostral whey was 36.56 ppm. Main amino acids contained in alcalase F-1 were Thr (15.45%), Glu (14.12%), and Ser (10.39%). Therefore, alcalase can be used to generate good iron-binding peptides in heated colostral whey, and the resulting iron-binding peptides could be suitable as a value-added food ingredient for food supplements.

• Korean Journal of Environmental Agriculture
• /
• v.17 no.1
• /
• pp.22-25
• /
• 1998

These studies were conducted to develope analysis method of herbicide quizalofop-ethyl by Gas Liquid Chromatography(GLC) and Enzyme-Linked Immunosoment Assay(ELISA) in soil and plant. Quizalofop produced by hydrolysis of quizalofop-ethyl was conjugated with bovine serum albumin(BSA). Quizalofop antibody was developed in rabbits by using BSA conjugation. Antibody titer, incubation temperature, and incubation time was 32,000, $37^{\circ}C$ and 4hours respectively. Minimum detection limit of quizalofop-ethyl by ELISA was 5ppb. Quizalofop-ethyl recovery from soil by ELISA was more than 95percent. Minimum detection limit of quizalofop-ethyl by GLC was 5ppb. Quizalofop-ethyl recovery from soil by GLC was from 89 percent to 100 percent. Minimun detection limit of quizalofop-ethyl by HPLC was 100ppb. Quizalofop-ethyl recovery from soil by HPLC was 89.6 percent.

• The Journal of the Korean Society for Microbiology
• /
• v.22 no.4
• /
• pp.377-392
• /
• 1987

Monoclonal antibody to the Escherichia coli heat-stable enterotoxin(ST) was produced to develop a rapid and convenient diagnostic method to the ST. The toxin was purified from culture supernatant of enterotoxigenic E. coli O148H28($ST^+/LT^+$) and conjugated to bovine serum albumin(BSA). The ST-BSA conjugate was used to immunize BALB/c mice and the immune spleen cells from these mice were fused with $P3{\times}63$ Ag8.V653 plasmacytoma cells. Hybridomas were screened by ELISA and positive hybridomas were cloned by limiting dilution. Finally, one stable clone (AS36) specific to ST was selected for further growth and characterization. Antibody titers of culture supernatant and ascitic fluid from BALB/c mice were 1:1,024 and 1:20,480 respectively in ELISA. The isotype and subclass of monoclonal antibody was IgG1 in sandwich ELISA. To test the neutralizing effect of monoclonal antibody on toxin activity of ST, mixture of ascitic fluid and ST was assayed by infant mouse assay and this monoclonel antibody was proved to be a neutralizing antibody. The titer of ascitic fluid which completely neutralized biological activity of 4 units of ST was 1:4. Purified ST was quantitatively measured by competitive ELISA and minimum amount of ST detectable by this assay was 250pg, which was an amount six-fold smaller than that detectable by infant mouse assay. Four reference strains of enterotoxigenic E. coli from WHO were detected by competitive ELISA and highly specific, sensitive and reproducible result was obtained.

• Journal of Dairy Science and Biotechnology
• /
• v.30 no.1
• /
• pp.17-22
• /
• 2012

Since the prevalence of allergies is increasing, food allergy is a major concern for consumers, as well as for the food industry. The foods that account for over 90% of all moderate to severe allergic reactions to food are milk, eggs, peanuts, soybeans, fish, shellfish, wheat, and tree nuts. Of these food allergens, milk is one of the major animal food allergens in infants and young children. Milk is the first food that an infant is exposed to; therefore, the sensitization rate of milk in sensitive individuals is understandably higher. The mechanisms involved in allergic reactions caused by this hypersensitivity are similar to those of other immune-mediated allergic reactions. The reactions occur in the gastrointestinal tract, skin, and respiratory tract, with headaches and psychological disorders occurring in some instances. The major allergenic proteins in milk are casein, ${\beta}$-lactoglobulin, and ${\alpha}$-lactalbumin, while some of the minor allergenic proteins are lactoferrin, bovine serum albumin, and immunoglobulin. Reliable allergen detection and quantification are essential for compliance with food allergen-labeling regulations, which protect the consumer and facilitate international trade.

• Korean Journal of Animal Reproduction
• /
• v.10 no.1
• /
• pp.76-82
• /
• 1986

This experiment was conducted to determine the effects of trophoblastic vesicles (TV) and estradiol-17$\beta$ on the development in vitro of rabbit embryos. Thirty matured female rabbits were treated with PMSG followed by HCG injection and mating. Embryos were recovered with D-PBS (Dulbecco's Phosphate Buffered Saline) after superovulation, and normally developed to two-to four-cell embryos were used in the subsequent in vitro culture. Basal medium was Medium-199 su, pp.emented with 1.5% bovine serum albumin. Embryo on Day 5 after mating (Day 0) was cut into two or three pieces to remove the embryonic disc. Each piece of tissue was cultured for 24 hours at 37$^{\circ}C$ in 0.5 mlMedium-199 in 5% CO2. During culture, peices of trophoblastic tissue changed into spherical vesicles which were used for co-culture. These spheres were called trophoblstic vesicles. Two-to four-cell embryos were cultured for 4 days in Medium-199 in the absence or presence of trophoblastic vesicle, and two-to four-cell embryos cultured with varing concentration (0, 0.1, 1, 10ng/ml) of estradiol-17$\beta$ for 4 dyas. Culture vessels used were watch glass for coculture with trophoblastic vesicles and micortube for estradiol-17$\beta$ infusion. Compared with the Medium-199 alone as basal culture medium, more blastocysts (46.7% vs 15.1%; P<0.01) and morulae (84.4% vs 56.6%; P<0.05) were developed in the co-culture with trophoblastic vesicles. Estradiol-17$\beta$ infused in culture medium was not effective for embryo development to blastocysts (78.3% in control, 50.0% in 0.1ng/ml, 61.5% in 1ng/ml and 64.4% in 10ng/ml) and also to morulae (91.3% in control, 84.2% in 0.1ng/ml, 92.3% in 1ng/ml and 91.1% in 10ng/ml). Compared with the watch glass culture mehotd, more (P<0.01) blastocysts were developed in microtube culture (78.3% vs 56.6%) and more (P<0.01) morulae in microtube culture (91.3% vs 56.6%).