인수공통 감염증의 하나인 톡소포자충의 검출을 위해서는 대부분은 ELISA 법이 사용 되고 있으나, 충체가 사멸 된 후에도 양성반응이 나타나는 등 사용에 제한이 있다. 반면 유전자 검출법은 현재 감염상태를 확인 할 수 있기 때문에 식중독 원인조사 등에 적합하다고 판단되어 이를 활용하여 본 연구를 진행하였다. 톡소포자충의 유전정보를 통해 529 repeat region의 염기서열을 얻고, 프라이머 및 TaqMan 프로브를 설계하여 real-time PCR을 이용한 검 출법을 개발하였다. 검출한계(lower limit of detection) 및 적정곡선을 확인한 결과 10 genomic DNA copy가 검출한 계로 확인되었고, 정량을 위한 곡선은 101~106 DNA copies 까지 0.999의 R2값을 나타내었다. 개발된 검출법의 증폭효 율을 비교하기 위해 B1 gene 타겟 프라이머 세트와 타입 별 검출한계를 비교한 결과, type 1, 2, 3 톡소포자충에서 같거나 더 나은 검출한계를 보였다. 또한 식품에서 주로 분리되는 식중독 세균 14종 및 원충 3종에 대해 특이도를 비교한 결과, 모두 음성으로 나타났다. 개발된 검출법을 식육검체에 적용하였을 때 type 1, 2, 3에서 모두 원활한 검출결과를 보여 증폭방해물질이 존재하지 않은 것으로 확인되었다. 본 연구를 통해 개발된 유전자검출법은 국내 유통 중인 식육에서 인수 공통감염 원충의 하나인 톡소포 자충의 감염 여부를 확인하는 사전적 모니터링의 방법으로 활용될 예정이다.

현대인들의 건강에 대한 관심이 커짐에 따라 한약재 소비량이 지속적으로 증가하고 있다. 그러나 최근 기후변화와 국내 한약재의 높은 수입 의존도에 따라 유해물질에 대한 오염 위험이 높아지고 있다. 곰팡이독소는 한약재 중 안전성을 평가하는 주요한 항목 중 하나이다. 본 연구에서 498 건의 한약재에 대해 곰팡이독소 모니터링을 진행 하였다. 면역컬럼을 이용해 한약재 중 아플라톡신을 추출 하였으며, 추출한 아플라톡신은 HPLC-FLD 방법을 통해 분석하였다. 직선성, 회수율, LOD 및 LOQ를 통해 본 연구에 이용한 실험법 검증을 실시하였다. 39건에서 평균 7.670 μg/kg의 아플라톡신이 검출되었으며, 0.610~77.452 μg/kg의 검출범위를 보였다. 특히 현호색은 국내 아플라톡신 기준이 없으나, 시험에 사용된 39건 중 5건에서 14.9 ± 4.1 μg/kg의 높은 아플라톡신 농도를 보였다. 즉, 현호색에 대한 기준 설정이 시급히 요구되어지며, 선제적 관리를 위한 지속적인 모니터링이 필요할 것으로 사료되어진다.

Salt, as food, is the most essential element for human survival due to its significant physiological functions. Here, we report the simultaneous detection of Pb and Cd in sea salt by square wave anodic stripping voltammetry (SWASV). Stripping voltammetric measurements were conducted using a manufactured rotating disk electrode system (MRDES). The detection limit was 3.6±0.18 µgL− 1 for Pb and 3.9±0.37 µgL− 1 Cd in NaCl solution. When the pH increased from 5.5 to 8.5, the peak currents of Pb and Cd decreased. At a pH of 8.3, the ratio of the current drop compared with that at a pH of 5.5 was 0.6 for Pb and 0.73 for Cd. The concentrations corrected by the current drop are in agreement with the concentrations obtained with ICP (inductively coupled plasma). This system demonstrates the reliable detection of heavy metals in aqueous media and, at a high Na + concentration, the successful application for the determination of Pb and Cd in sea salts.

Salt, as food, is the most essential element for human survival due to its significant physiological functions. Here, we report the simultaneous detection of Pb and Cd in sea salt by square wave anodic stripping voltammetry (SWASV). Stripping voltammetric measurements were conducted using a manufactured rotating disk electrode system (MRDES). The detection limit was 3.6±0.18 μgL−1 for Pb and 3.9±0.37 μgL−1 Cd in NaCl solution. When the pH increased from 5.5 to 8.5, the peak currents of Pb and Cd decreased. At a pH of 8.3, the ratio of the current drop compared with that at a pH of 5.5 was 0.6 for Pb and 0.73 for Cd. The concentrations corrected by the current drop are in agreement with the concentrations obtained with ICP (inductively coupled plasma). This system demonstrates the reliable detection of heavy metals in aqueous media and, at a high Na + concentration, the successful application for the determination of Pb and Cd in sea salts.

For preliminary molecular typing, PCR-based fingerprinting using random amplified polymorphic DNA (RAPD) is the method of choice. In this study, 14 bacterial strains were isolated from different Korean food sources, identified using 16S rRNA gene sequencing, and characterized through RAPD-PCR. Two PCR primers (239 and KAY3) generated a total of 130 RAPD bands, 14 distinct PCR profiles, 10 polymorphic bands, one monomorphic band, and four unique bands. Dendrogram-based analysis with primer 239 showed that all 14 strains could be divided into seven clades out of which clade VII had the maximum of seven. In contrast, dendrogram analysis with the primer KAY3 divided the 14 L. citreum strains into four clades out of which clade IV consisted of a maximum of 10 strains out of 14. This research identified and characterized bacterial populations associated with different Korean foods. The proposed RAPD-PCR method, based on sequence amplification, could easily identify and discriminate the lactic acid bacteria species at the strain-specific level and could be used as a highly reliable genomic fingerprinting tool.

For preliminary molecular typing, PCR-based fingerprinting using random amplified polymorphic DNA (RAPD) is the method of choice. In this study, 14 bacterial strains were isolated from different Korean food sources, identified using 16S rRNA gene sequencing, and characterized through RAPD-PCR. Two PCR primers (239 and KAY3) generated a total of 130 RAPD bands, 14 distinct PCR profiles, 10 polymorphic bands, one monomorphic band, and four unique bands. Dendrogram-based analysis with primer 239 showed that all 14 strains could be divided into seven clades out of which clade VII had the maximum of seven. In contrast, dendrogram analysis with the primer KAY3 divided the 14 L. citreum strains into four clades out of which clade IV consisted of a maximum of 10 strains out of 14. This research identified and characterized bacterial populations associated with different Korean foods. The proposed RAPD-PCR method, based on sequence amplification, could easily identify and discriminate the lactic acid bacteria species at the strain-specific level and could be used as a highly reliable genomic fingerprinting tool.

청국장추출물과 청국장의 주요한 플라보노이드의 하나인 genistein의 HepG2 세포에서 Trp-P-1 유도 세포독성과 DNA손상에 대한 보호효과를 평가하였다. 청국장추출물과 주요 플라보노이드성분 genistein은 Trp-P-1 유도 세포독성에 대하여 세포독성보호효과를 나타내었다. 청국장추출물 은 Trp-P-1 유도 DNA single strand breaks를 억제하였다. 한편, 청국장추출물은 HepG2 세포에서 Trp-P-1 유도에 의한 CYP1A1와 CYP1A2 발현의 억제를 나타내었다. 청국 장추출물과 genistein은 Trp-P-1에 의한 유도 세포독성과 DNA손상에 대하여 CYP1A1, CYP1A2 발현억제에 의하 여 보호효과가 나타나는 것으로 판단된다. 한국의 전통 콩 발효식품인 청국장은 게놈 불안정성(genomic instability)을 일으키는 heterocyclic amines (HCAs)과 같은 식품의 가열 조리로부터 올 수 있는 발암물질에 대한 유전독성을 예방할 수 있는 유망한 기능성물질로서 활용가능성이 있을 것으로 판단된다.

Purple-fleshed potato powder (PFPP) was investigated to determine optimal mixing ratio with milk powder and dextrin to produce a ready-to-eat mashed potato powder. The rheological characteristics, color, and anthocyanin contents were studied at a different concentration of ingredients. The power-law model was applied to explain the mechanical spectra of mashed potatoes which represented the change in structure induced by different mixing ratios. Mixture design was used to obtain the experimental points used to establish the empirical models to describe the effects of each ingredient on the characteristic of the mashed potato. The results of mechanical spectra showed that both storage and loss moduli (G' and G'') were significantly influenced by PFPP and milk powder concentration. The power law parameters n' and n'' showed higher values for the mashed potato with a lower concentration of PFPP and a higher concentration of milk powder, which showed that the gel networks involved in the mashed potato were weaker. The optimum mixing ratio with the highest redness and anthocyanin content, while maintaining the rheological properties similar to the commercial mashed potato, was determined as PFPP:milk powder:dextrin = 90.49:4.86:4.65 (w/w). The proportions of PFPP and milk powder in the formulation significantly changed the characteristics of mashed potato, whereas no significant effect of dextrin was observed in this formulation.

Purple-fleshed potato powder (PFPP) was investigated to determine optimal mixing ratio with milk powder and dextrin to produce a ready-to-eat mashed potato powder. The rheological characteristics, color, and anthocyanin contents were studied at a different concentration of ingredients. The power-law model was applied to explain the mechanical spectra of mashed potatoes which represented the change in structure induced by different mixing ratios. Mixture design was used to obtain the experimental points used to establish the empirical models to describe the effects of each ingredient on the characteristic of the mashed potato. The results of mechanical spectra showed that both storage and loss moduli (G' and G'') were significantly influenced by PFPP and milk powder concentration. The power law parameters n' and n'' showed higher values for the mashed potato with a lower concentration of PFPP and a higher concentration of milk powder, which showed that the gel networks involved in the mashed potato were weaker. The optimum mixing ratio with the highest redness and anthocyanin content, while maintaining the rheological properties similar to the commercial mashed potato, was determined as PFPP:milk powder:dextrin = 90.49:4.86:4.65 (w/w). The proportions of PFPP and milk powder in the formulation significantly changed the characteristics of mashed potato, whereas no significant effect of dextrin was observed in this formulation.

Although Semisulcospira libertina is generally regarded as a supplement for the alleviation of alcohol hangover, little is known about its effects on cell metabolism. Therefore, this study was conducted to analyze the constituents of the extracts prepared using different extraction methods and to compare their biochemical properties. The amino acid contents were found to be much higher in acidic and enzymatic hydrolysates than hot water extracts from S. libertina. DPPH radical scavenging activities in acidic and enzymatic hydrolysates were higher than those of hot water extracts. Three types of S. libertina hydrolysate was added to HepG2 cells damaged by acetaminophen (AAP), after which the survival rate of HepG2 cell were measured. In addition, lactate dehydrogenase (LDH) activities in the culture media were evaluated. The survival rates of HepG2 cells were 77.0±4.3% and 81.5±1.3% at 3 h and 5h enzymatic hydrolysates, respectively. These cell survival rates were higher compared to those of the negative control group (67.8±4.3%) treated only with acetaminophen. Cellular toxicities induced by treatment with AAP were also significantly alleviated in response to treatment with the extracts of S. libertina. In addition, the activities of 2 key enzymes that metabolize ethanol, alcohol dehydrogenase and aldehyde dehydrogenase, were upregulated by 4.7- and 2.7-fold respectively in response to treatment with a 3 h enzymatic hydrolysate of S. libertina. Taken together, these results provide biochemical evidence of the method by which S. libertina exerts its biological functions, including the alleviation of alcohol hangover and the protection of liver cells against toxic insults.

Although Semisulcospira libertina is generally regarded as a supplement for the alleviation of alcohol hangover, little is known about its effects on cell metabolism. Therefore, this study was conducted to analyze the constituents of the extracts prepared using different extraction methods and to compare their biochemical properties. The amino acid contents were found to be much higher in acidic and enzymatic hydrolysates than hot water extracts from S. libertina. DPPH radical scavenging activities in acidic and enzymatic hydrolysates were higher than those of hot water extracts. Three types of S. libertina hydrolysate was added to HepG2 cells damaged by acetaminophen (AAP), after which the survival rate of HepG2 cell were measured. In addition, lactate dehydrogenase (LDH) activities in the culture media were evaluated. The survival rates of HepG2 cells were 77.0±4.3% and 81.5±1.3% at 3 h and 5h enzymatic hydrolysates, respectively. These cell survival rates were higher compared to those of the negative control group (67.8±4.3%) treated only with acetaminophen. Cellular toxicities induced by treatment with AAP were also significantly alleviated in response to treatment with the extracts of S. libertina. In addition, the activities of 2 key enzymes that metabolize ethanol, alcohol dehydrogenase and aldehyde dehydrogenase, were upregulated by 4.7- and 2.7-fold respectively in response to treatment with a 3 h enzymatic hydrolysate of S. libertina. Taken together, these results provide biochemical evidence of the method by which S. libertina exerts its biological functions, including the alleviation of alcohol hangover and the protection of liver cells against toxic insults.

The objective of this study was to determine the effect of moisture contents (40, 50, 60%) and CO2 gas injection (0 and 800 mL/min) on physicochemical properties of extruded soy protein isolate (SPI). The expansion ratio and the specific length increased, but piece density decreased with the increase in CO2 gas injection from 0 to 800 mL/ min at both 40 and 50% moisture contents. On the contrary, the expansion ratio and the specific length decreased, but piece density increased with the increase in CO2 gas injection from 0 to 800 mL/min at 60% moisture content. Extruded SPI with CO2 gas injection at 800 mL/min had small cell size and higher amount of cell than extruded SPI without CO2 gas injection. The water holding capacity and nitrogen solubility index increased, and the integrity index and the texture decreased with the increase in CO2 gas injection from 0 to 800 mL/min. In conclusion, extruded SPI with the CO2 gas injection at 800 mL/min showed better expansion properties and cell formation than extruded SPI without the CO2 gas injection.

The objective of this study was to determine the effect of moisture contents (40, 50, 60%) and CO2 gas injection (0 and 800 mL/min) on physicochemical properties of extruded soy protein isolate (SPI). The expansion ratio and the specific length increased, but piece density decreased with the increase in CO2 gas injection from 0 to 800 mL/ min at both 40 and 50% moisture contents. On the contrary, the expansion ratio and the specific length decreased, but piece density increased with the increase in CO2 gas injection from 0 to 800 mL/min at 60% moisture content. Extruded SPI with CO2 gas injection at 800 mL/min had small cell size and higher amount of cell than extruded SPI without CO2 gas injection. The water holding capacity and nitrogen solubility index increased, and the integrity index and the texture decreased with the increase in CO2 gas injection from 0 to 800 mL/min. In conclusion, extruded SPI with the CO2 gas injection at 800 mL/min showed better expansion properties and cell formation than extruded SPI without the CO2 gas injection.

This study was carried out to investigate antimicrobial activity and characteristics of Asparagus cochinchinenesis which was steamed and fermented with lactic acid bacteria. A. cochinchinensis was prepared to steaming process which was washed and freeze dried. A. cochinchinensis was steamed at 95oC for 12 h and dried by hot air at 50oC for 24 h. After steaming process, A. cochinchinensis was fermented with lactic acid bacteria (Leuconostoc mesenteroides 4395, Lactobacillus sakei 383 and Lactobacillus plantarum KCCM 11322). Ethyl acetate extracts of fermented A. cochinchinensis had antimicrobial activities for the respiratory disease bacteria (Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa and Escherichia coli). A. cochinchinensis had highest antimicrobial activity for the P. aeruginosa which fermented with L. mesenteroides 4395. The minimum inhibition concentration (MIC) of A. cochinchinensis fermented with L. mesenteroides 4395 was 10 mg/mL for S. aureus, S. epidermidis, E. coli and 5 mg/mL for P. aeruginosa. The MIC of A. cochinchinensis fermented with L. sakei 383 and A. cochinchinensis fermented with L. plantarum KCCM 11322 were the same. Total sugar was decreased from 863.33±17.47 mg/mL to 722.67±5.51 mg/mL during the steaming process. But reducing sugar was increased from 99.36±1.32 mg/mL to 109.29±2.71 mg/mL during the steaming process. Total sugar was decreased to 301.50-361.42 mg/mL and reducing sugar was decreased to 27.39-62.20 mg/mL during the fermentation process.

This study was carried out to investigate antimicrobial activity and characteristics of Asparagus cochinchinenesis which was steamed and fermented with lactic acid bacteria. A. cochinchinensis was prepared to steaming process which was washed and freeze dried. A. cochinchinensis was steamed at 95oC for 12 h and dried by hot air at 50oC for 24 h. After steaming process, A. cochinchinensis was fermented with lactic acid bacteria (Leuconostoc mesenteroides 4395, Lactobacillus sakei 383 and Lactobacillus plantarum KCCM 11322). Ethyl acetate extracts of fermented A. cochinchinensis had antimicrobial activities for the respiratory disease bacteria (Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa and Escherichia coli). A. cochinchinensis had highest antimicrobial activity for the P. aeruginosa which fermented with L. mesenteroides 4395. The minimum inhibition concentration (MIC) of A. cochinchinensis fermented with L. mesenteroides 4395 was 10 mg/mL for S. aureus, S. epidermidis, E. coli and 5 mg/mL for P. aeruginosa. The MIC of A. cochinchinensis fermented with L. sakei 383 and A. cochinchinensis fermented with L. plantarum KCCM 11322 were the same. Total sugar was decreased from 863.33±17.47 mg/mL to 722.67±5.51 mg/mL during the steaming process. But reducing sugar was increased from 99.36±1.32 mg/mL to 109.29±2.71 mg/mL during the steaming process. Total sugar was decreased to 301.50-361.42 mg/mL and reducing sugar was decreased to 27.39-62.20 mg/mL during the fermentation process.

This study investigated the possible use of enzymatically hydrolyzed isolated soy protein (eHISP) to enhance the intensity of salty taste. The sodium chloride content of eHISP is 69.5 g/L. Yellowness (b) increased, and lightness (L) and redness (a) decreased with increasing eHISP concentration in sample solution. Also, perceived salty intensity of eHISP solution increased in sample solution with increasing added amount of eHISP with same NaCl concentration. The intensity of the salty taste was enhanced by 2-39% as the eHISP was added. The results suggest that it may be possible to reduce the content of sodium chloride in foods by enhancing the salty taste with eHISP.

This study investigated the possible use of enzymatically hydrolyzed isolated soy protein (eHISP) to enhance the intensity of salty taste. The sodium chloride content of eHISP is 69.5 g/L. Yellowness (b) increased, and lightness (L) and redness (a) decreased with increasing eHISP concentration in sample solution. Also, perceived salty intensity of eHISP solution increased in sample solution with increasing added amount of eHISP with same NaCl concentration. The intensity of the salty taste was enhanced by 2-39% as the eHISP was added. The results suggest that it may be possible to reduce the content of sodium chloride in foods by enhancing the salty taste with eHISP.

The purpose of this study was to optimize dough properties using response surface methodology (RSM) and to demonstrate the performances of dough prepared under optimized conditions. Dough mixed with yeast, margarine, salt, sugar and wheat flour was prepared by fermentation process. Hardness, cohesiveness and springiness of dough were selected as critical quality attributes. The critical formulations (yeast and water) and process (fermentation time) variables were selected as critical input variables based on preliminary experiment. Box-Behnken design (BBD) was used as RSM. As a result, the quardratic, the squared and the linear model respectively provided the most appropriate fit (R2>90) and had no significant lack of fit (p>0.05) on critical quality attributes (hardness, cohesiveness and springiness). The accurate prediction of dough characteristics was possible from the selected models. It was confirmed by validation that a good correlation was obtained between the actual and predicted values. In conclusion, the methodologies using RSM in this study might be applicable to the optimization of fermented foods containing various wheat flour and yeast.

The purpose of this study was to optimize dough properties using response surface methodology (RSM) and to demonstrate the performances of dough prepared under optimized conditions. Dough mixed with yeast, margarine, salt, sugar and wheat flour was prepared by fermentation process. Hardness, cohesiveness and springiness of dough were selected as critical quality attributes. The critical formulations (yeast and water) and process (fermentation time) variables were selected as critical input variables based on preliminary experiment. Box-Behnken design (BBD) was used as RSM. As a result, the quardratic, the squared and the linear model respectively provided the most appropriate fit (R2>90) and had no significant lack of fit (p>0.05) on critical quality attributes (hardness, cohesiveness and springiness). The accurate prediction of dough characteristics was possible from the selected models. It was confirmed by validation that a good correlation was obtained between the actual and predicted values. In conclusion, the methodologies using RSM in this study might be applicable to the optimization of fermented foods containing various wheat flour and yeast.

Millimeter waves are electromagnetic waves with frequencies of 30–300 GHz (wavelength 1–10 mm), and millimeter wave stimulation affects microorganism growth. The present study stimulated Bacillus subtilis with 60 and 70 GHz millimeter waves during cheonggukjang fermentation and characterized the effects on cheonggukjang quality. Cheonggukjang treated with millimeter wave irradiation showed no significant difference in total bacterial count but generated only 5.52-5.92% viscous substance. Irradiation with 60 GHz millimeter waves yielded bright and intense color values relative to 70 GHz millimeter waves. Examination of the amylase activity and reducing sugar content of finished cheonggukjang revealed that irradiation at 70 GHz inhibited amylase activity in cheonggukjang. Furthermore, irradiation at 70 GHz increased protease activity, whereas irradiation at 60 GHz inhibited the activity. Moreover, the amino acid content changed with millimeter wave irradiation.