• Food Science of Animal Resources
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• v.29 no.4
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• pp.437-444
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• 2009

${\gamma}-Aminobutyric$ acid (GABA) producing lactic acid bacteria, Lactobacillus acidophilus RMK567 was cultivated in 50 L of sterilized MRS broth using a fermenter at $40^{\circ}C$ for 24 h. The cell number was increased to $10.04{\pm}0.13$ Log CFU/mL with a growth rate constant (k) of 0.454 generation/h and a generation time (g) of 2.303 h after a lapse of a lag phase (L) of 5.16 h. A total of 487 g of cell paste with 40.5% moisture was harvested with viable cell number of 12.48 Log CFU/g cell paste. The cell pastes after preparation with glycerol, glucose, and polydextrose as cryo-protectants were lyophilized under a vacuum of 84 m torr. A total of 408 g of freeze dried (FD) cell powders were mixed with a commercial strain of Streptococcus thermophilus to prepare of three types FD starter cultures with the viable cell numbers of 12.42 (FDA-GY), 12.60 (FDBGG) and 12.91 (FDC-GP) Log CFU/g. During preservation the FD cultures at -$18^{\circ}C$, the cell viability of the FD starter cultures were rapidly dropped to below 3.24% of the day of storage. No significant difference was found in the cell viabilities among three types of FD starters cultures, but significant difference (p<0.01) was found in storage periods. Yoghurts fermented through FD starter culture of L. acidophilus RMK567 were determined to contain $155.16{\pm}8.53$ ppm, $243.82{\pm}4.27$ ppm, and $198.64{\pm}23.46$ ppm of GABA, respectively. This study shows that GABA production activity of L. acidophilus RMK567 is not affected during the freeze drying process and would be available for commercial production of yoghurt containing high GABA content.

• Food Science and Preservation
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• v.23 no.4
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• pp.591-598
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• 2016

The purpose of this study was to screen desirable yeast strains for alcoholic fermentation of tomato paste without sugar addition. The moisture, crude protein, crude fat, ash, and soluble nitrogen contents of the tomato paste ($25^{\circ}Brix$) were found to be 67.33%, 1.90%, 0.03%, 0.02%, and 30.72%, respectively. Free sugars found in the paste were fructose and glucose. Most abundant free amino acids of the paste were glutamic, aspartic, and ${\gamma}$-aminobutyric acids. Total seven yeast strains (Saccharomyces cerevisiae KDH (TWA), S. cerevisiae Lalvin ICVD-47 (TWB), S. cerevisiae Lalvin RC-212 (TWC), S. cerevisiae Lalvin K1-V1116 (TWD), S. bayanus Lalvin EC-1118 (TWE), S. cerevisiae Enoferm (TWF), and S. cerevisiae DJ97(KCTC8842P) (TWG)) were tasted for alcohol fermentation of the tomato paste. The highest alcohol content (8.2%) and the lowest residual sugar content ($13.25^{\circ}Brix$) were observed in the tomato paste fermented using the S. cerevisiae Lalvin ICVD-47 strain (TWB) after 3 day and 4 day of fermentation, respectively. Sugar and reducing sugar contents, and pH of the tomato paste were not remarkably affected by the difference in yeast strains used, showing $13.25{\sim}13.45^{\circ}Brix$, 28.37~28.48 mg/mL, and 4.43~4.54, respectively, after 4 day of fermentation. Color and total acid content were significantly affected by the types of yeast strains and fermentation time, but the numerical changes were negligible. These results indicate that TWB would be the suitable strain for alcoholic fermentatiom of tomato paste based on its highest alcohol production and the lowest residual sugar content produced during fermentation.

• Journal of Life Science
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• v.25 no.1
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• pp.68-74
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• 2015

Recently developed black waxy rice with a giant embryo ('Nunkeunheukchal', BGE) was selected and processed to produce high quality nutritional food. BGE contains high levels of several phytochemicals with antioxidant activities, as well as other reported health beneficial properties. In addition, the giant embryo has high protein, lipid, and amino acids contents. Within the free amino acids, ${\gamma}$-aminobutyric acid (GABA), a major inhibitory neurotransmitter, has long been used for treating the aftereffects of brain injuries and stroke. A method for manufacturing pop-rice and black rice tea by popping process in BGE is provided to increase a taste, nutrition and functionality. The produced 'pop-rice' showed increased protein (11.3%) and lipid (3.7%) contents compared with control variety, IB ('Ilmibyeo'). In addition, melanoidin related products, polyphenol and functional amino acid contents were increased by the popping process. Pop-rice tea made of BGE showed the highest extraction of total sugar, glucose, raffinose and sucrose (4 times higher than brown rice) by hot water. Scavenging activity ($SC_{50}$) of processed BGE rice powder showed strong antioxidative activity of 0.24 mg/ml using DPPH and 1.82 mg/ml using ABTs method. Thereafter, these results suggested that the popping processed rice of BGE could be one of the promising materials for healthy food development.

• Journal of Life Science
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• v.32 no.8
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• pp.601-610
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• 2022

P. tenebrifer (PT) belongs to the Diptera order and Stratiomyidae family. Recently, insect industry have been focused as food, animal feed and environmental advantages. γ-aminobutyric acid (GABA) and melatonin have been associated with regulating sleep and depression. GABA is the primary inhibitory neurotransmitter and is synthesized via biotransformation of monosodium glutamate (MSG) to GABA by lactic acid bacteria. In this study, we first used a GABA-enhanced PT extract, wherein GABA was enhanced by feeding MSG to PT. The underlying mechanisms preventing stress and insomnia were investigated in a corticosterone (CORT)-induced endoplasmic reticulum (ER) stress and chronic restraint stress (CRS)-exposed mouse model, as well as in pentobarbital (45 mg/kg)-induced sleep behaviors in mice. In the present study, the GABA peak was detected in high-performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD) analysis and showed in Ptecticus tenebrifer water extract (PTW) but not in non-PTW extract. The results showed that PTW and Ptecticus tenebrifer with 70% ethanol extract (PTE) exerted neuroprotective effects by protecting against CORT-induced downregulation of phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2) and cAMP-response element binding protein (CREB) expression. In addition, PTW (300 mg/kg) significantly reduced CORT levels in CRS-exposed mice. Furthermore, PTW (100 and 300 mg/kg) significantly reduced sleep latency and increased total sleep duration in pentobarbital (45 mg/kg)-induced sleeping behaviors, which was related to serum melatonin levels. In conclusion, our results suggest that PTW exerts anti-stress and sleep-enhancing effects by regulating serum CORT and melatonin levels.

• Journal of Life Science
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• v.30 no.3
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• pp.260-266
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• 2020

Alcohol impacts many central nervous systems, such as dopamine, serotonin, opioids, and gamma-aminobutyric acid (GABA), leading to addiction. Many studies have investigated the relationship between GABA and alcoholism. The purpose of this study was to investigate the effects of GABA high and low rice intake on the alcohol intake behavior of mice. Black sticky rice with giant embryo (BSRGE), black sticky rice (BSR), giant embryo rice (GER), and rice (Rice) were germinated for 48 hr in brown rice. The embryos were then collected and used in the study. The diets were fed to respective C57BL/6 mouse groups ad libitum for 16 days and investigated for 2 hr alcohol intake, 22 hr water intake, 24 hr feed intake, and body weight. As a result of the repeated measure of ANOVA for the daily change of alcohol intake for 2 hr daily between the BSRGE and BSR groups, there was a significant difference in the number of days of intake (DF = 7, F = 4.812, p = 0.026). A significant daily decrease in alcohol intake was observed in the BSRGE group compared to the BSR group. This reduction was consistent from Day 10 to Day 16. Alcohol consumption also significantly decreased in the GER group compared to the Rice group. This decrease was observed from Day 12 to Day 16. In conclusion, BSRGE and GER resulted in decreased alcohol intake in C57BL/6 mice compared to BSR and rice. This suggests that BSRGE may prevent relapse in patients with alcohol use disorder.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.9
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• pp.1081-1090
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• 2017

The purpose of this study was to develop a functional porridge prepared with mulberry leaf and mulberry fruit powder, which can ameliorate hypertension. The experiment was designed according to the central composite design. For optimization of the mixture ratio of mulberry leaf powder (MLP) and mulberry fruit powder (MFP), the independent variables were defined as MLP (X1) and MFP (X2) and the dependent variables were defined as K (Y1), Na (Y2), ${\gamma}$-aminobutyric acid (GABA) (Y3), cyanidin-3-glycoside (C3G) (Y4), rutin (Y5), and flavonoid (Y6). The optimal MLP to MFP mixture ratio according to the response surface method were 5.41 g of MLP and 2.65 g of MFP. The amounts of K, Na, GABA, C3G, rutin, and flavonoid in the optimal MLP and MFP mixture were 1,844.22 mg/100 g, 52.74 mg/100 g, 139.98 mg/100 g, 1,134.89 mg/100 g, 101.56 mg/100 g, and 201.28 mg/100 g, respectively. The amounts of Ca, K, Mg, and Na in the functional porridge at this optimal point were 27.66 mg/100 g, 131.32 mg/100 g, 19.57 mg/100 g, and 3.59 mg/100 g, respectively. Overall, this functional porridge can help reduce hypertension.

• The Korean Journal of Food And Nutrition
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• v.29 no.2
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• pp.145-152
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• 2016

This study investigated the changes in chemical components, antioxidant compounds, and activity before (BG) and after germinated (AG) brown rice in order to promote the availability of these beneficial factors. The GABA content of BG and AG brown rice were 0.07~6.61 and 11.13~49.72 mg/100 g, respectively. The ${\alpha}$-amylase activity of AG brown rice was 1.77~70.25 unit/g fold higher than it was in BG brown rice. Total polyphenol and flavonoid contents, which are known to be related to antioxidation, were higher in BG brown rice than in AG brown rice. The total polyphenol contents of BG and AG brown rice were 10.52~36.38 and 11.38~26.33 mg/100 g, and the total flavonoid contents were 3.55~13.39 and 3.52~9.78 mg/100 g, respectively. Also, DPPH radical scavenging activity was 57.64~251.34 and 50.49~213.35 mg TE/100 g, respectively. ABTS radical scavenging activity and total tannin content showed a similar trend to DPPH radical scavenging activity. We expect that this data will be useful in the manufacturing of food products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.8
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• pp.1128-1135
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• 2011

Changes in the chemical components of three cereals, foxtail millet, proso millet, and sorghum, during germination were determined. The crude protein contents of the three cereals did not significantly change during germination, whereas the contents of total dietary fiber of the three cereals increased during germination. The contents of ${\gamma}$-aminobutyric acid (GABA) of Whanggeum-cho (347.4 ${\mu}g/g$), Chongcha-cho (336.5 ${\mu}g/g$), Bulgeun-gijang (347.4 ${\mu}g/g$), Noranchal-gijang (344.9 ${\mu}g/g$), Whanggeumchal-susu (410.4 ${\mu}g/g$), and Whinchal-susu (444.0 ${\mu}g/g$) increased after 24, 24, 84, 36, 48, and 72 hr of germination, respectively, and then sharply decreased. The contents of total polyphenols, flavonoids, and tannin in foxtail millet, proso millet, and Whinchal-susu tended to increase during germination. However, the total phenolic content of Whanggeumchal-susu greatly decreased by 48 hr of germination and then considerably increased, whereas the total flavonoid content of Whanggeumchal-susu greatly decreased during germination. Total tannin content of Whanggeumchal-susu greatly decreased by 36 hr of germination and then slowly increased. DPPH radical scavenging activity of Whanggeumchal-susu greatly decreased by 36 hr of germination and then remained constant, whereas those of other cereals did not greatly change during germination. These results indicate that there are some differences in the chemical components of three cereals during germination.

• Journal of Food Hygiene and Safety
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• v.34 no.2
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• pp.124-134
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• 2019

An analytical method was developed for the determination of broflanilide and its metabolites in agricultural products. Sample preparation was conducted using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method and LC-MS/MS (liquid chromatograph-tandem mass spectrometer). The analytes were extracted with acetonitrile and cleaned up using d-SPE (dispersive solid phase extraction) sorbents such as anhydrous magnesium sulfate, primary secondary amine (PSA) and octadecyl ($C_{18}$). The limit of detection (LOD) and quantification (LOQ) were 0.004 and 0.01 mg/kg, respectively. The recovery results for broflanilide, DM-8007 and S(PFP-OH)-8007 ranged between 90.7 to 113.7%, 88.2 to 109.7% and 79.8 to 97.8% at different concentration levels (LOQ, 10LOQ, 50LOQ) with relative standard deviation (RSD) less than 8.8%. The inter-laboratory study recovery results for broflanilide and DM-8007 and S (PFP-OH)-8007 ranged between 86.3 to 109.1%, 87.8 to 109.7% and 78.8 to 102.1%, and RSD values were also below 21%. All values were consistent with the criteria ranges requested in the Codex guidelines (CAC/GL 40-1993, 2003) and the Food and Drug Safety Evaluation guidelines (2016). Therefore, the proposed analytical method was accurate, effective and sensitive for broflanilide determination in agricultural commodities.