• 농업과학연구
• /
• 제47권3호
• /
• pp.645-655
• /
• 2020

Bacteria are a very common cause of food poisoning. Moreover, bacteria form biofilms to protect themselves from harsh environments. Conventional detection methods for foodborne bacterial pathogens including the plate count method, enzyme-linked immunosorbent assays (ELISA), and polymerase chain reaction (PCR) assays require a lot of time and effort. Hyperspectral imaging has been used for food safety because of its non-destructive and real-time detection capability. This study assessed the feasibility of using hyperspectral imaging and machine learning techniques to detect biofilms formed by Escherichia coli. E. coli was cultured on a high-density polyethylene (HDPE) coupon, which is a main material of food processing facilities. Hyperspectral fluorescence images were acquired from 420 to 730 nm and analyzed by a single wavelength method and machine learning techniques to determine whether an E. coli culture was present. The prediction accuracy of a biofilm by the single wavelength method was 84.69%. The prediction accuracy by the machine learning techniques were 87.49, 91.16, 86.61, and 86.80% for decision tree (DT), k-nearest neighbor (k-NN), linear discriminant analysis (LDA), and partial least squares-discriminant analysis (PLS-DA), respectively. This result shows the possibility of using machine learning techniques, especially the k-NN model, to effectively detect bacterial pathogens and confirm food poisoning through hyperspectral images.

• 한국토양비료학회지
• /
• 제47권4호
• /
• pp.275-283
• /
• 2014

The ${\gamma}$-oryzanol, ferulic acid esters, which are well-known for their function on cholesterol lowering and prevention of inflammation, diabetes and cancer, are found in the seeds of cereal crops such as rice, corn, wheat and rye. Among them, rice has been reported to contain the highest ferulic acid esters. Since rice cultivation with green manure as a N source is an environmental friendly agricultural practice, it is necessary to identify and quantify as well as evaluate the variations in these compounds in rice samples as affected by different green manure conditions. A total of ten components of ${\gamma}$-oryzanol were isolated and cycloartenyl ferulate, 24-methylenecycloartanyl ferulate, campesteryl ferulate and sitosteryl ferulate were identified as the major components in Korean rice cultivars, 'Unkwang' and 'Hopum'. Comparing the ${\gamma}$-oryzanol contents of these varieties, 'Unkwang' showed clearly similar pattern with conventional type. With the PLS-DA (partial least squares of discriminant analysis) using SIMCA 11.0 ver., the specific pattern and cluster of ${\gamma}$-oryzanol scores with green manure conditions were confirmed, and thus distinguishing green manure effects were possible.

• 한국축산식품학회지
• /
• 제42권2호
• /
• pp.341-349
• /
• 2022

The objective of this study was to examine the effect of temperature abuse prior to cold storage on changes in quality and metabolites of frozen/thawed beef loin. The aerobic packaged samples were assigned to three groups: refrigeration (4℃) (CR); freezing (-18℃ for 6 d) and thawing (20±1℃ for 1 d), followed by refrigeration (4℃) (FT); temperature abuse (20℃ for 6 h) prior to freezing (-18℃ for 6 d) and thawing (20±1℃ for 1 d), followed by refrigeration (4℃) (AFT). FT and AFT resulted in higher volatile basic nitrogen (VBN) values than CR (p<0.05), and these values rapidly increased in the final 15 d. Cooking loss decreased significantly with an increase in the storage period (p<0.05). In addition, cooking loss was lower in the FT and AFT groups than in the CR owing to water loss after storage (p<0.05). A scanning electron microscope (SEM) revealed that frozen/thawed beef samples were influenced by temperature abuse in the structure of the fiber at 15 d. Metabolomic analysis showed differences among CR, FT, and AFT from partial least square discriminant analysis (PLS-DA) based on proton nuclear magnetic resonance (¹H NMR) profiling. The treatments differed slightly, with higher FT than AFT values in several metabolites (phenylalanine, isoleucine, valine, betaine, and tyrosine). Overall, temperature abuse prior to freezing and during thawing of beef loin resulted in accelerated quality changes.

• 한국미생물·생명공학회지
• /
• 제51권2호
• /
• pp.147-156
• /
• 2023

Tetragenococcus halophilus CY54, an isolate from jeotgal, grows best in media with 5% NaCl and can grow at 18% and higher salt concentration. Three different doenjang samples were prepared with multiple starters including T. halophilus CY54. TBZA doenjang was prepared with T. halophilus, Bacillus subtilis, Zygosaccharomyces rouxii and Aspergillus oryzae. BZA doenjang was prepared with the same 3 starters except T. halophilus. KACC doenjang was prepared with a single starter, B. subtilis KACC16750. During 16 weeks of fermentation at 25℃, the viable counts were maintained in the range of 7-8 log CFU/g in all 3 samples. As fermentation progressed, pH decreased and titratable acidity (TA) gradually increased. Crude protein contents decreased slightly. TBZA doenjang showed higher amino-type nitrogen (ANN) and volatile basic nitrogen (VBN) contents, and KACC doenjang showed higher ammonia-type nitrogen (AMN) content. TBZA doenjang showed higher fibrinolytic and protease activity than other doenjang samples. Metabolites analyses by GC/MS showed that doenjang samples were separated from each other by partial least squares-discriminant analysis (PLS-DA) analysis. Seventeen major metabolites involved in the differences between samples were identified and they included organic acids, amino acids, sugars, fatty acids and alcohols. TBZA doenjang showed higher contents for most metabolites responsible for flavor and taste of fermented foods including doenjang. These results showed that T. halophilus could be useful as a starter for doenjang and can improve the product quality by accelerating the fermentation processes.

• Journal of Nutrition and Health
• /
• 제51권4호
• /
• pp.275-286
• /
• 2018

본 연구는 떫은감 청도반시의 분말을 열수 추출하고 칼럼 추출하는 과정에서 획득한 PWE와 TEP에 대한 대사체 프로파일을 분석하고, 유리지방산을 처리한 HepG2 세포와 식이로 고지혈증을 유도한 Wistar계 흰쥐의 간조직을 사용하여 중성지질 및 콜레스테롤 대사 관련 유전자 발현을 측정하였다. 대사체 분석은 가스크로마토그래프-질량분석법과 액체크로마토그래프-질량분석법을 사용하였으며, PLS-DA 분석과 heatmap 분석을 실시한 결과 PWE는 떫은감 분말과 비교적 유사한 대사체 프로파일을, 그리고 TEP는 떫은감 분말과 매우 다른 대사체 프로파일을 가지고 있음을 확인하였다. 세포실험과 또한 세포실험에서 얻어진 결과를 검증하기 위해 수행된 동물실험에서 PWE와 TEP는 모두 SREBP1c와 FAS 유전자 발현을 감소하여 간의 지방축적을 감소시키는 것으로 관찰되었으나, 콜레스테롤 축적을 억제하는 효능은 PWE에 비해 TEP에서 우세하게 증가하는 것이 관찰되었다. 특별히 TEP는 SREBP2, HMGCR 유전자 발현을 억제하고 LDLR 유전자 발현을 촉진하는 것으로 나타났다. TEP는 탄닌 중 Gallic acid 그리고 장쇄지방산아미드인 Oleamide와 Palmitamide 함량이 유의하게 증가되었으므로, 향후 이들 성분과 타깃 유전자의 상관성을 분석하고, 이를 통해 시스템네트워크로 나타내어 대사체 프로파일에 따른 지질 및 콜레스테롤 대사 간 상호 영향을 추가적으로 연구해야 할 것으로 사료된다.

• 한국환경농학회지
• /
• 제34권2호
• /
• pp.98-104
• /
• 2015

BACKGROUND: ${\gamma}$-Oryzanol, a mixture of ferulic acid esters of triterpene alcohols and sterols, are a nutritionally important group of rice secondary metabolites. The ${\gamma}$-Oryzanol content and composition were found to vary with enviromental factors such as growth temperature, varietal origin, and cultivation method. Therefore, the effect of green manure treatments will be also be an important factor in their content. METHODS AND RESULTS: The ${\gamma}$-Oryzanols extracted using dichloromethane/methanol were analyzed equipped liquid chromatography with a diode array detector. A total of ten components of ${\gamma}$-oryzanol including ${\Delta}7$-stigmastenyl ferulate were isolated of which, cycloartenyl ferulate, 24-methylenecycloartanyl ferulate, campesteryl ferulate and sitosteryl ferulate were identified as the major components in Korean rice variety, Unkwang. The ${\gamma}$-oryzanol content in rice, in the presence of nitrogen fertilization using green manure was similar to conventional nitrogen fertilization, but was higher than the control(no fertilizations). The ${\gamma}$-oryzanol ontent in rice, in the presence of hairy vetch as green manure crop was the highest compared to other crops (opium-poppy, crimson clover, cornflower). As a result of PLS-DA using SIMCA 11.0 ver. as multivariate analysis program on the basis of total data, in all samples, the specific pattern and cluster of ${\gamma}$-oryzanol scores according to green manure crops and conditions were confirmed with possible distinguishing nitrogen effects. CONCLUSION: The nitrogen contained in the green manure crops is considered to play a major role in the formation of ${\gamma}$-oryzanol. Hairy vetch which contains higher nitrogen increased the concentration of ${\gamma}$-oryzanol in rice.

• Journal of Pharmaceutical Investigation
• /
• 제39권1호
• /
• pp.29-36
• /
• 2009

Since the quality of final products is significantly affected by the homogeneity of powder mixture, the powder blending process has been regarded as one of the critical pharmaceutical unit processes, especially for solid dosage forms. Accordingly, the monitoring to determine a blending process' end-point based on a faster and more accurate in-line/on-line analysis has attracted enormous attentions recently. Among various analytical tools, NIR (near-infrared) spectroscopy has been extensively studied for PAT (process analytical technology) system due to its many advantages. In this study, NIR spectroscopy was employed with an optical fiber probe for the in-line monitoring of fluid-bed blending process. The position of the probe, the ratio of binary powder mixture, the powder size differential and the back-flush period of the shaking bag were examined as principal process parameters. During the blending process of lactose and mannitol powders, NIR spectra were collected, corrected, calibrated and analyzed using MSC and PLS method, respectively. The probe position was optimized. A reasonable end-point was predicted as 1,500 seconds based on 5% RSD value. As a consequence, it was demonstrated that the blending process using a fluid-bed processor has several advantages over other methods, and the application of NIRS with an optical fiber probe as PAT system for a fluid-bed blending process could be high feasible.

• Journal of Microbiology and Biotechnology
• /
• 제27권5호
• /
• pp.925-932
• /
• 2017

Changes in the metabolite profiles of Lactobacillus sakei and its growth media, based on different culture times (0, 6, 12, and 24 h), were investigated using gas chromatography-mass spectrometry (MS) and liquid chromatography-MS with partial least squares discriminant analysis, in order to understand the growth characteristics of this organism. Cell and media samples of L. sakei were significantly separated on PLS-DA score plots. Cell and media metabolites, including sugars, amino acids, and organic acids, were identified as major metabolites contributing to the difference among samples. The alteration of cell and media metabolites during cell growth was strongly associated with energy production. Glucose, fructose, carnitine, tryptophan, and malic acid in the growth media were used as primary energy sources during the initial growth stage, but after the exhaustion of these energy sources, L. sakei could utilize other sources such as trehalose, citric acid, and lysine in the cell. The change in the levels of these energy sources was inversely similar to the energy production, especially ATP. Based on these identified metabolites, the metabolomic pathway associated with energy production through lactic acid fermentation was proposed. Although further studies are required, these results suggest that MS-based metabolomic analysis might be a useful tool for understanding the growth characteristics of L. sakei, the most important bacterium associated with meat and vegetable fermentation, during growth.

• Journal of Ginseng Research
• /
• 제42권4호
• /
• pp.485-495
• /
• 2018

Background: The geographical origin of Panax ginseng Meyer, a valuable medicinal plant, is important to both ginseng producers and consumers in the context of economic profit and human health benefits. We, therefore, aimed to discriminate between the cultivation regions of ginseng using the stable isotope ratios of C, N, O, and S, which are abundant bioelements in living organisms. Methods: Six Korean ginseng cultivars (3-yr-old roots) were collected from five different regions in Korea. The C, N, O, and S stable isotope ratios in ginseng roots were measured by isotope ratio mass spectrometry, and then these isotope ratio profiles were statistically analyzed using chemometrics. Results: The various isotope ratios found in P. ginseng roots were significantly influenced by region, cultivar, and the interactions between these two factors ($p{\leq}0.001$). The variation in ${\delta}^{15}N$ and ${\delta}^{13}C$ in ginseng roots was significant for discriminating between different ginseng cultivation regions, and ${\delta}^{18}O$ and ${\delta}^{34}S$ were also affected by both altitude and proximity to coastal areas. Chemometric model results tested in this study provided discrimination between the majority of different cultivation regions. Based on the external validation, this chemometric model also showed good model performance ($R^2=0.853$ and $Q^2=0.738$). Conclusion: Our case study elucidates the variation of C, N, O, and S stable isotope ratios in ginseng root depending on cultivation region. Hence, the analysis of stable isotope ratios is a suitable tool for discrimination between the regional origins of ginseng samples from Korea, with potential application to other countries.

• 한국프랜차이즈경영연구
• /
• 제10권1호
• /
• pp.43-52
• /
• 2019

Purpose - Many companies use the Internet to conduct their business to maintain and acquire their customers. SNS is used as a site where users can create profiles, build personal networks, and then share and exchange information with others. Not only do people use SNS for their self-promotion, but they also promote their services by creating SNS pages. SNS is recognized as a medium for implementing effective advertising strategies and is being used as an important means of promoting the company. Therefore, in this study, we investigate the effect of SNS marketing characteristics of restaurant franchise firms on utilitarian value and hedonic value and examine their effects on purchase intention. Research design, data, and methodology - The data were collected from 20s-60s respondents who have used SNS for restaurant visit using Google survey. A total of 159 responses were collected and used for final analysis. Smart PLS 3.0 was used for the hypothesis test. Results - As a result of an analysis, it was shown that the influence of the playfulness and affordability of information on the utilitarian value had a significant positive effect. Interaction and up-to-date did not have a positive effect on utilitarian value. Interaction, affordability, and up-to-date have no significant positive effects on hedonic value. The playfulness of information has a positive effect on the hedonic value. Both utilitarian value and hedonic value had positive effects on purchase intention. Conclusions - The findings of this study suggest that the SNS marketers of restaurant franchisors should focus on the playfulness, affordability, and up-to-date rather than the interactivity of SNS. In marketing through SNS, the act of presenting the basis of information and enhancing the provision of information through objective criteria makes it possible to experience the practical value of information. It is necessary to develop differentiated contents which cause customers interest and fun and to induce many customers' purchase intent by providing objective and realistic information. In order to increase the customers' repurchase intentions toward the food service business, customers should maximize the hedonic value and practical value felt through information. It should also focus on providing information that customers are receptive to, rather than providing prompt information.