• Proceedings of the PSK Conference
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• 2000.04a
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• pp.198.1-198.1
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• 2000

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.370-374
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• 2007

An analytical method for the simultaneous determination of four tetracycline (oxytetracycline, tetracycline, chlortetracycline, doxycycline) in egg samples was developed and validated using liquid chromatography with ultraviolet detection. Egg samples were extracted by the liquid-liquid extraction based on acetonitrile. The chromatographic separation was achieved on a reverse phase C8 column with gradient elution using a mobile phase of 20 mM oxalic acid (pH 1.5)/acetonitrile. The procedure was validated according to the Food Drugs Administration guideline determining accuracy, precision, and limit of detection. Mean recovery of tetracyclines from spiked egg samples (50, 100, 200, 400, and $800{\mu}g/kg$) were 78.8-109.3%. Linearity in concentration range of $50-800{\mu}g/kg$ was obtained with the correlation coefficient $(r^2)$ of 0.994-0.999. The intra- and inter-day precision (relative standard deviation; RSD) was between 0.3-12.8 and 0.2-11.7%, respectively. Limit of detection (LOD) and limit of quantification (LOQ) for the investigated tetracyclines were 30 and $50{\mu}g/kg$ depending on egg samples, respectively. This method was reliable, sensitive, economical and suitable for routine monitoring of tetracycline residues in dairy egg.

• Food Science of Animal Resources
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• v.18 no.3
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• pp.269-275
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• 1998

The purpose of this study was to determine the thermal inactivation of Salmonella enteritidis, Salmonella typhimurium and E. coli O111 in liquid cultures treated with microwave energy. Furthermore, this study was to introduce new methodologies for studying nonthermal microwave effects on microorganisms, using controlled microwave energy and specially designed apparatuses. For the automatic temperature control during microwave heating, the real time data acquisition and computation system is designed with BASIC routine. The automatic temperature control system used in the experiments perform relatively stable control at the experiment temperature of 45, 50, 55 60$^{\circ}C$ and 65$^{\circ}C$ for 30 minutes. The effects of microwave heating on liquid cultures was compared with that of conventional heating, still reduces effectively the number of pathogenic bacteria in liquid cultures. While no particular differences between microwave heating and conventional heating was observed in the activation of E. coli at 45$^{\circ}C$ test, the activation of Sal. enteritidis and Sal. typhimurium was slightly reduced during the microwave treatments.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.10a
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• pp.335-343
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• 2011

We examined the effect of the acidic liquid from carbonized rice hull(ALCRH) treatments to molded fiber packages(MFP) on weight, Haugh unit, pH and microbial activity of egg to extend the shelf life in egg packaging. Higher concentration and surface spray treatment of the acidic liquid extended the shelf life of egg. ALCRH treatment to MFP improved the performance of the packaging for egg in terms of decreased weight loss and retarded microorganism growth of eggs during storage.

• Journal of Nutrition and Health
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• v.50 no.6
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• pp.543-551
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• 2017

Purpose: The objective of the present study was to determine whether fermentation can increase the protective effects of blueberry liquid in a high-fat diet-induced obese mice model. Methods: Male C57BL/6J mice were fed a high-fat diet (HD, 60% fat, w/w,), HD supplemented with 10 ml/kg BW/day of blueberry liquid (BHD, blueberry high-fat diet), or HD supplemented with 10 ml/kg BW/day of fermented blueberry liquid (FBHD, fermented blueberry high-fat diet) for 10 weeks. Results: There were significant decreases in the body, epididymal adipose tissue, and liver weights of blueberry-fed groups compared to HD, whereas there were no significant differences in food intake among the groups. Furthermore, blueberry liquid groups, especially fermented blueberry liquid, significantly attenuated the contents of hepatic triglycerides and total cholesterol induced by HD. Serum LDL-cholesterol was significantly lower in the BHD and FBHD-fed groups, whereas FBHD significantly increased the serum HDL-cholesterol level compared to the control. Concentrations of aspartate transaminase, alanine transaminase, and leptins in serum were also reduced by blueberry liquid supplementation. The mRNA expression of hepatic acetyl CoA carboxylase was significantly reduced in both the BHD and FBHD groups compared to HD. Furthermore, FBHD altered the mRNA expression level of hepatic lipolysis genes. Conclusion: In conclusion, these results suggest that blueberry, especially fermented blueberry liquid, may improve obesity-related abnormalities.

• Korean journal of food and cookery science
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• v.21 no.1 s.85
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• pp.1-11
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• 2005

The application of Dongchimi liquid into Naengmyon broth for the improved eating quality of Naengmyon was scientifically explored by reviewing the quality properties of the product. Primarily, the optimum fermentation conditions for Dongchimi from which the liquid portion was extracted were pursued and the optimum mixing ratio was sought on the basis of sensory and microbiological properties of the product. The liquid portions which had been periodically extracted from Dongchimi at intervals of two or five days during fermentation at $10^{\circ}C$ were added to Naengmyon broth. The treatments were prepared with three levels, namely, basic broth only('A') and the ratios of 3:7(v/v, 'B') and 5:5(v/v, 'C') of Dongchimi liquid and basic broth, respectively. According to assessments of Dongchimi liquid on taste and intensity based on sensory analyses, the organoleptic factors such as color, smell, sour taste, carbonated taste, and overall acceptability were given higher values from day 11 to day 17 in all items. As for the assessment of Dongchimi liquid on intensity, color, sour odor, moldy odor, and carbonated taste have shown the increasing scores during with high intensities while those for clearness has stayed low. Most of the phenomena observed from the Naengmyon broth substituted with $30\%$ (Treatment 'A') and $50\%$ (Treatment 'B') of Dongchimi liquids with different storage periods ensued much of the previous fermentation pattern of Dongchimi itself. Organoleptic assessment on taste and its intensity showed that better(the best) scores could be obtained at between day 16$\~$25(17) and 13$\~$20(15) for Treatments A and B, respectively. The intensity scores of taste for color, smell, carbonated taste, sour taste, and mouthfeel were increased while those for clearness, palatability, and meaty ones were decreased with lapse of fermentation. The numbers of total cell and lactic acid bacterial counts of Dongchimi has increased until day 13 and then decreased in the later stages. Total cell count and lactic acid bacterial counts of Naengmyon broth also increased until the 13th day and then they began to decrease. It was also proven that slightly over-ripened Dongchimi liquid was more preferable for adding into Naengmyon broth. Granting the optimum ripening period of Dongchimi liquid itself to be 13 days, both Treatment A and Treatment B were evenly favored using Dongchimi liquids slightly over-ripened at days 13 to 17. However, Treatment A was more favored than Treatment B when Dongchimi liquid over-ripened for 20 to 26 days was used.

• Journal of Food Hygiene and Safety
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• v.35 no.4
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• pp.326-333
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• 2020

In this work, we developed an analytical method for determining 11 illicit compounds in dietary supplements using high-performance liquid chromatography and liquid chromatography-tandem mass spectrometry. Eleven target compounds, including those meant for weight loss (7-keto-dihydroepiandrosterone, buformin, metformin, phenformin, salbutamol, and tolbutamide), sexual enhancement (dihydroepiandrosterone), and relaxation (asarone, kavain, magnoflorine, and picamilon) were screened and confirmed in dietary supplements. Method validation was performed by evaluating the selectivity, linearity, limit of quantification (LOQ), accuracy, and precision according to the Association of Official Analytical Chemists guidelines. The linearity was > 0.993 for all analytes. The LOQs were ranged in 2.1-9.9 ㎍/mL (HPLC-DAD) and 0.002-0.008 ㎍/mL (LC-MS/MS). The accuracies (expressed as recovery) were 90.0-106% (HPLC-DAD) and 83.0-114% (LC-MS/MS). The precision (expressed as the relative standard deviation) was below 10% using HPLC and LC-MS/MS. The proposed method can be used for the surveillance of illicit compounds in dietary supplements.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.246-253
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• 2016

The antibacterial activities of thirty mushroom species belonging to Basidiomycetes and Ascomycetes, cultivated on two liquid media, were evaluated against gram-positive (Bacillus subtilis and Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria by the disk diffusion method. All of the mushrooms, except Auriporia aurea, Fomes fomentarius, and Lyophyllum shimeji, showed different antibacterial activity levels—from 9.5 mm in diameter of the inhibition zone to full inhibition of growth of the test bacteria. The antibacterial activities of Crinipellis schevczenkovi, Hohenbuehelia myxotricha, Oxyporus obducens, and Spongipellis litschaueri were observed for the first time. The antibacterial potential of culture liquids of the investigated species was higher than that of their mycelia activity. Dependence of the intensity of antibacterial activity on the culture medium was shown. The antibacterial efficiency of the most active species (Lentinus edodes, Piptoporus betulinus, and Phellinus igniarius) was verified and compared with those of some commercial antibiotics and natural essential oils of Salvia and Eucalyptus. The culture liquid of Piptoporus betulinus, obtained after cultivation on glucose-peptone-yeast culture medium, is a potential substance for further creation of antibacterial products.

• Analytical Science and Technology
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• v.25 no.1
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• pp.76-82
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• 2012

The determination and confirmation of dutasteride in human serum was performed by a liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI/MS/MS). Beclomethasone as an internal standard (I.S.) was added to the serum and the mixed sample was pretreated by liquid-liquid extraction (LLE) with methyl tert-butyl ether (MTBE). The mass transitions of dutasteride and I.S. monitored in multiple reaction monitoring (MRM) were m/z 529.6${\rightarrow}$461.5 and m/z 409.3${\rightarrow}$391.2, respectively, and the retention times were 6.45 and 5.46 min, respectively. The calibration curve was linear in the concentration range of 0.5~30.0 ng/mL ($R^2$= 0.9999) and the limit of quantitation (LOQ) was found to be 0.5 ng/mL. The recovery of dutasteride was shown to be 66~72%. The intra-day assay precision and accuracy were in the range 3.5~5.5% and 85.7~89.9%, respectively, and the interday assay precision and accuracy were in the range 4.2~5.8% and 90.8~95.8%, respectively.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 1996.11a
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• pp.106-106
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• 1996