• Journal of Life Science
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• v.28 no.5
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• pp.577-586
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• 2018

We recently reported the potential probiotic properties of Lactobacillus brevis SBB07 isolated from blueberries. The present study investigates the effect of culture conditions such as temperature, initial pH, culture time, and medium constituent for industrial application. The ingredients of the medium to improve cell growth were selected by Plackett-Burman design (PBD) and central composite design (CCD) within a desirable range. The PBD was applied with 19 factors: seven carbon sources, six nitrogen sources, and six microelements. Protease peptone, corn steep powder (CSP), and yeast extract were found to be significant factors for the growth of SBB07. The CCD was then applied with three variables found from the PBD at five levels, and the optimum values were decided for the three variables: protease peptone, CSP, and yeast extract. In the case of the growth of SBB07, the proposed optimal media contained 2.0% protease peptone, 2.5% CSP, and 2.0% yeast extract, and the maximum dried-cell weight was predicted to be 2.93963 g/l. By the model verification, it was confirmed that the predicted and actual results are similar. Finally, the study investigated the effects of incubation temperature and initial pH at the optimized medium. It was confirmed that the dried-cell weight increased from $2.2933{\pm}0.0601g/l$ to $3.85{\pm}0.0265g/l$ when compared to the basal medium at $37^{\circ}C$ and initial pH 8.0. Establishing the optimal culture condition for SBB07 provides good potential for applications in probiotics and can serve as the foundation for the industrialization of materials.

• Food Science and Preservation
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• v.23 no.6
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• pp.797-803
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• 2016

In this study, we investigated the effect of fermentation conditions on the amylolytic and proteolytic activities of Aspergillus luchuensis strain 74-5 and Aspergillus oryzae strain 75-2, which are used in the preparation of the starter culture, for Takju (Korean traditional rice wine). The starter culture was optimized using different conditions, such as inoculum size, inoculation temperature, and incubation time. The enzyme activities under each condition were measured. In the A. luchuensis strain 74-5 starter culture, the ${\alpha}-amylase$ and glucoamylase activities increased, however the activity of acidic protease decreased as the diluent to starter culture ratio increased. In the A. oryzae 75-2 starter culture, all enzyme activities were maintained at a higher level even at 5% inoculation ratio. Higher enzyme activities were observed in the middle range of inoculation temperature (35, $40^{\circ}C$), than in the lower range (20, $30^{\circ}C$). Enzyme activity in the starter culture varied with incubation time, however it was the highest at 144 and 120 hr, respectively, for A. luchuensis strain 74-5 and A. oryzae strain 75-2. The spore count of the starter culture was approximately $2{\times}10^7$ during fermentation, out of which contamination by aerobic bacteria was about $3{\times}10^3$. The results suggested that the starter culture of each strain could be used as an inoculum for fermentation. However, we needs to conduct further research for the selection of suitable diluting agents as well as drying methods to reduce the contamination by aerobic bacteria, while retaining the enzyme activity.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.401-416
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• 2011

The recent trend for pesticide residue analysis in food involves fast cleanup and use of mass spectrometry to achieve quantitative and qualitative analysis at the same time. Recently, the QuEChERS (quick, easy, cheap, effective, rugged and safe) multi-reside method has received much attention as a fast extraction and cleanup method of pesticide residue analysis. Therefore, multi-residue analysis of 236 pesticides was tested with the QuEChERS method by concurrent use of PTV-GC/TOFMS (gas chromatography/ time-of-flight mass spectrometry with programmable temperature vaporizer). PTV condition was optimized and when the method was applied to apples, pesticide recovery rates (spiked at 400 ng/g) ranged from 80% to 120%, and RSD values were under 10% for most compounds. The results showed that the QuEChERS sample preparation and PTV-GC/TOFMS analysis can be applied to multi-residue analysis of pesticides in fruits and vegetables.

• Microbiology and Biotechnology Letters
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• v.26 no.3
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• pp.250-256
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• 1998

D-Tagatose production from D-galactose was investigated using 35 type strains of American Culture Type Collection (ATCC) and Korean Collection for Type Cultures (KCTC) which have potential to produce D-tagatose. Enterobacter agglomerans ATCC 27987 was selected as a D-tagatose producing strain due to its short fermentation time and high production of D-tagatose. Optimization of the culture conditions for D-tagatose production by E. agglomerans ATCC 27987 was performed. Among various carbon sources, D-galactose was the most effective carbon source for D-tagatose production. As the D-galactose concentration was increased, cell growth and D-tagatose production increased. Effect of nitrogen sources on D-tagatose production was studied. Of inorganic nitrogen sources, ammonium sulfate was effective one for D-tagatose production and yeast extract was the most suitable organic nitrogen nutrient. The concentrations of inorganic compounds such as KH$_2$PO$_4$, K$_2$HPO$_4$, and MgSO$_4$$.$7H$_2$O were also optimized for D-tagatose production. The optimal medium was determined to contain D-galactose of 20 g/l, yeast extract of 5.0 g/l, (NH$_4$)$_2$SO$_4$ of 2.0 g/l, KH$_2$PO$_4$ of 5.0 g/l, K$_2$HPO of 5.0 g/l, and MgSO$_4$$.$7H$_2$O of 5 mg/l. The optimal environmental conditions in a 250-$m\ell$ flask were found to be pH of 6.0, temperature of 30$^{\circ}C$, and agitation speed of 150 rpm. D-tagatose of 0.41 g/l could be obtained in 24 h from 20 g/l D-galactose at the optimal culture condition without induction and cell concentration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.1
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• pp.93-101
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• 2014

Asymmetric 1,2-distearoyl-3-oleoyl-rac-glycerol (SSO) triacylglycerol (TAG) is used as a cocoa butter replacer (CBR). In this study, it was produced by lipase-catalyzed interesterification of fully hydrogenated soybean oil (FHSBO) and oleic ethyl ester (OEE) in a batch type reactor at $75^{\circ}C$, 250 rpm. Different molar ratios (FHSBO : OEE=1:1, 1:2 and 1:3, w/w) and various reaction times (1, 2, 3, 4, and 5 hr) were also tested. The optimized condition for SSO was a FHSBO : OEE molar ratio of =1:1 at reaction times of 2, 3, 4, and 5 hr. Enzymatic synthesis generated SSO/SOS, as well as the other TAGs (e.g., PSO/POS, SOO/OSO, SSS), ethyl esters, monoacylglycerol (MAG), and diacylglycerol (DAG). After scale-up, fractionation by solvent (methanol and acetone) fractionation and column chromatography was applied. To reduce ethyl esters, high-melting TAGs (e.g., SSS), and SOO/OSO in reactants, solvent fractionation was applied. Using a silica gel column (sample : silica gel=2:1, wt%), MAG and DAG were removed at $25^{\circ}C$. The major fatty acid composition of the final products (with a high SSO/SOS content) was palmitic acid (C16:0, 10.9~12.9 area%), stearic acid (C18:0, 52.2~54.9 area%), and oleic acid (C18:1, 34.2~35.5 area%). In reversed-phase HPLC analysis, the major TAG species of the final product (FHSBO : OEE=1:1, 2 hr) were SSO/SOS (82.31 area%) and PSO/POS (14.51 area%). Based on the $[SS]^+$ : $[SO]^+$ ratio obtained by RP-HPLC/APCI-MS, the final product had a higher SSO (AAB type TAG) content than cocoa butter (CB). The solid fat index (SFI) of CB and the final product obtained were similar with a narrow melting point range around ~32 to $35^{\circ}C$.

• Progress in Medical Physics
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• v.23 no.2
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• pp.106-113
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• 2012

The purpose of this study is to evaluate the variation of radiation dose distribution for liver tumor located in liver dome and for the interest organs(normal liver, kidney, stomach) with the pencil beam convolution (PBC) algorithm versus anisotropic Analyticalal algorithm (AAA) of the Varian Eclipse treatment planning system, The target volumes from 20 liver cancer patients were used to create treatment plans. Treatment plans for 10 patients were performed in Stereotactic Body Radiation Therapy (SBRT) plan and others were performed in 3 Dimensional Conformal Radiation Therapy (3DCRT) plan. dose calculation was recalculated by AAA algorithm after dose calculation was performed by PBC algorithm for 20 patients. Plans were optimized to 100% of the PTV by the Prescription Isodose in Dose Calculation with the PBC algorithm. Plans were recalculated with the AAA, retaining identical beam arrangements, monitor units, field weighting and collimator condition. In this study, Total PTV was to be statistically significant (SRS: p=0.018, 3DCRT: p=0.006) between PBC and AAA algorithm. and in the case of PTV, ITV in liver dome, plans for 3DCRT were to be statistically significant respectively (p=0.013, p=0.024). normal liver and kidney were to be statistically significant (p=0.009, p=0.037). For the predictive index of dose variation, CVF ratio was to be statistically significant for PTV in the liver dome versus PTV (SRS r=0.684, 3DCRT r=0.732, p<0.01) and CVF ratio for Tumor size was to be statistically significant (SRS r=-0.193, p=0.017, 3DCRT r=0.237, p=0.023).

• Journal of Nutrition and Health
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• v.52 no.6
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• pp.515-528
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• 2019

Purpose: This study examined the immunological activity and optimized the mixture conditions of Sargassum horneri (S. horneri) extracts in vitro and in vivo models. Methods: S. horneri was extracted using three different methods: hot water extraction (HWE), 50% ethanol extraction (EE), and supercritical fluid extraction (SFE). Splenocyte proliferation and cytokine production (Interleukin-2 and Interferon-γ) were measured using a WST-1 assay and enzyme-linked immunosorbent assay, respectively. The levels of nitric oxide and T cell activation production were measured using a Griess assay and flow cytometry, respectively. The natural killer (NK) cell activity was determined using an EZ-LDH kit. Results: Among the three different types of extracts, HWE showed the highest levels of splenocyte proliferation and cytokine production in vitro. In the animal model, three different types of extracts were administrated for 14 days (once/day) at 50 and 100 mg/kg body weight. HWE and SFE showed a high level of splenocyte proliferation and cytokine production in the with and without mitogen-treated groups, whereas EE administration did not induce the splenocyte activation. When RAW264.7 macrophage cells were treated with different mixtures (HWE with 5, 10, 15, 20% of SFE) to determine the optimal mixture ratio of HWE and SFE, the levels of nitric oxide and cytokine production increased strongly in the HWE with 5% and 10% of SFE containing group. In the animal model, HWE with 5% and 10% of SFE mixture administration increased the levels of splenocyte proliferation, cytokine production, and activated CD4⁺ cell population significantly, with the highest level observed in the HWE with 5% of SFE group. Moreover, the NK cell activity was increased significantly in the HWE with 5% of SFE mixture-treated group compared to the control group. Conclusion: The optimal mixture condition of S. horneri with immune-enhancing activity is the HWE with 5% of SFE mixture. These results confirmed that the extracts of S. horneri and its mixtures are potential candidate materials for immune enhancement.

• Proceedings of the Korea Hospitality Industry Research Society Conference
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• 2002.11a
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• pp.83-98
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• 2002

The old testament of the Bible has written the milk and curd. God said, I will ive you to how the milk and honey. The present study was designed to examine the effects of different homogenization pressure, homogenization temperature and $\beta$-cyclodextrin concentration on cholesterol removal rate of cheese, and to optimize the factors of cheese manufacture Process. In addition, the characteristics from cholesterol removed cheese and control are compared in the rheological and ensory analysis. The optimized process condition for cholesterol removal was for homogenization pressure, 74$^{\circ}C$ for homogenization temperature and 2% for $\beta$-cyclodextrin concentration, it showed 875% of the highest cholesterol removal rate in milk. Therefore, manufacture conditions of cholesterol removed cheese were chosen 74$^{\circ}C$ for homogenization temperature, for homogenization pressure, and I or 2% for $\beta$-cyclodextrin concentration. Cholesterol removed cheese and control were compared with yield, cholesterol removal, meltability, stretchability, textural properties and sensory analysis. Cholesterol content of control cheese containing 23.8% milk fat was cheese made from milk treated with 2% $\beta$-cyclodextrin and homogenization pressure was cholesterol removal. Yield of cholesterol removed cheese. As the homogenization pressure increased, oiling off reduced with showed better surface appearance. Stretchability of cholesterol removed cheese was lower 5~10cm than over 30cm of control. Meltability of cholesterol removed cheese also was lower than control. The hardness, gumminess, chewiness reduced to respectively. In the result of sensory analysis, treatment of homogenization for cholesterol removed cheese improved appearance and flavor, however texture fell. In addition, the resent result of the study indicated that about 75% of cholesterol in cheese could be removed, and the possibility of development of cholesterol removed cheese was observed. We have hope to research manufacture cheese global wide.