• Korean Journal of Food Science and Technology
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• v.53 no.2
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• pp.204-212
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• 2021

Resazurin, an oxidized blue dye, is reduced to resorufin, showing a peak absorbance change and emitting fluorescence due to the metabolic activity of living cells. In this study, the growth of Lactobacillus rhamnosus GG (LGG) and the redox potential of living probiotic bacteria were evaluated based on changes in the absorbance or fluorescence of resazurin. Fluorescence analysis is a more accurate and sensitive method for quantifying viable LGG than the colorimetric absorbance measurement of resazurin change. Fluorescence measurement could detect LGG of 6.5-9.5 log CFU/mL within 30 min with R2=0.99. No significant effect of further reduction of resorufin to dihydroresorufin by LGG was observed. Various probiotics showed different resazurin-reducing activities, and L. kimchicus had the highest reducing activity among the six probiotics tested. These findings suggests that fluorescence measurement in a resazurin-based assay is useful for analyzing bacterial growth and the redox potential of living probiotics.

• Journal of the Korean Society of Radiology
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• v.15 no.1
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• pp.55-61
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• 2021

In this study, microbes were collected before and after disinfection using ANIOS(ANIOSURF Premium NPC) and compared the areas where the radiological technologist and the patient frequently contacted the chest X-ray. From September 1st to September 7th, 2020. in P Hospital in Deagu, 4 region were collected in a 10×10 size using a sterile cotton swab of the transport medium, and before and after disinfection results were obtained through the colorimetric method. As a result, n the X-ray tube handle Proteus mirabilis, Staphylococcus epidermidis, Bacillus spp., Candida spp., and in the Chin region Proteus mirabilis, Enterococcu faecium, Pseudomonas aeruginosa, NTM, and in the Chest region Proteus mirabilis, Enterococcu faecium, Pseudomonas aeruginosa, and in the Palm region NTM, Candida spp. were detected, and 103 CFU(Colony Forming Unit) or more were measured. After disinfection, only X-ray tube handle was detect Bacillus spp. and more than 102 CFU was measured. Microorganisms found prior to disinfection can cause opportunistic infections, Experimental results showed that Aniosulf(0.25%) is more economical and disinfectant than ethanol(70-90%) and isopropyl alcohol(70-90%). However, further research is needed on the detection of Bacillus spp. resultingly this research is useful basic data of infection control in Radiography room and prevention secondary infections.

• The Korea Journal of Herbology
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• v.28 no.1
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• pp.59-64
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• 2013

Objectives : Methicillin-Resistant Staphylococcus aureus (MRSA) is a cephalosporin and beta-lactam antibiotic-resistant strains. In most cases, that is spread from infected patients and infection rates are growing increasingly. Thus, accordingly, increased resistance to antibiotics is causing serious problems in the world. Therefore, there is a need to develop alternative antimicrobial drugs for the treatment of infections diseases. Methods : The antibacterial activities of Sinhyowoldosan were evaluated against 3 strains of Methicillin-resistant staphylococcus aureus(MRSA) and 1 standard Methicillin-susceptible S. aureus (MSSA) strain by using the disc diffusion method, minimal inhibitory concentrations (MICs) assay, colorimetric assay using MTT test, checkerboard dilution test and time-kill assay was performed under dark. Results : The MIC (minimum inhibitory concentration) of Sinhyowoldosan water extract against S. aureus strains ranged from 500 to 2,000 ${\mu}g/mL$, so we have confirmed it on a strong antibacterial effect. Also, the combinations of Sinhyowoldosan water extract and conventional antibiotics exhibited improved inhibition of MRSA with synergy effect. We suggest that Sinhyowoldosan water extract against MRSA have antibacterial activity, it has potential as alternatives to antibiotic agent. the combination test was used, Triton X-100 (TX) and DCCD for measurement of membrane permeability and inhibitor of ATPase. As a result, antimicrobial activity of SH is affected by the cell membrane were assessed. Conclusion : We suggest that the Sinhyowoldosan water extract lead the treatment of bacterial infection to solve the resistance and remaining side-effect problems that are the major weak points of traditional antibiotics.

• The Korea Journal of Herbology
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• v.33 no.3
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• pp.37-43
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• 2018

Objectives : Butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA) were well known as anti-oxidant, but they were limited to use because of toxicity. So, many studies are being done to develope natural anti-oxidant. Total phenolic and flavonoid contents along with total antioxidant capacity of the ethanolic extract of Plantaginis Herba (PH) were evaluated to explore the reliable and potential sources of novel natural antioxidants. Methods : Total polyphenol contents and total flavonoid contents in PH ethanol extract were determined by colorimetric method. And DPPH(1.1-diphenyl-2-picrylhydrazyl), ABTS(2'-azino-bis (3-ethylbenzothiazoline-6-Surfonicacid)) free radical scavenging capacity and reducing power inhibition activities of PH ethanol extract were measured at 100, 500, 1000, $5000{\mu}g/m{\ell}$ concentrations by spectrometric assay. Results : The total polyphenol contents and total flavonoid contents of the extract were 161.99 mg/g, 144.05 mg/g, respectively. Also, DPPH, ABTS free radical scavenging capacity and reducing power of PH ethanol extract in treated concentrations (100, 500, 1000, $5000{\mu}g/m{\ell}$) increased dose dependently. In particular, DPPH free radical scavenging capacity of PH ethanol extract from $500{\mu}g/m{\ell}$ was significantly increased compared to positive control (BHA). ABTS free radical scavenging capacity of PH ethanol extract from $1000{\mu}g/m{\ell}$ was significantly higher than BHA. Also, reducing power showed that PH ethanol extract from $500{\mu}g/m{\ell}$ was significantly increased compared to BHA. Conclusions : These results suggest that PH ethanol extract has effects to scavenge free radicals, thus PH has potential and applicable benefits for development of materials and products to have anti-oxidation functions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.4
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• pp.569-576
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• 2016

This study researched the effects of cooking methods on phytochemical-enriched thin rice porridge (RP) of three colors (red, yellow, and green). Each of the RPs was prepared by three cooking methods and retorted through two-steps (step 1, at $80^{\circ}C$ for 15 min; step 2, at $82^{\circ}C$ for 25 min) for pasteurization. Cooking method (CM) 1 involved heating a mixture of all ingredients while CM 2 involved addition of apple/beet (AB, red), sweet-pumpkin/cabbage (PC, yellow) or vitamin/pear (green) while heating rice flour and glutinous rice flour. CM 3 involved mixing pre-cooked fruits and vegetables with cooked thin RP. The viscosity of RP prepared by CM 1 was lower than those of other RPs (P<0.05). The result of colorimetric a value show that red and green color of AB and VP prepared by CM 2 and CM 3 were most vivid. Contents of phytochemicals and antioxidants were higher when RP was prepared by CM 2 and CM 3 compared to CM 1. ${\Delta}E$ values of PC showed no significant difference before and after pasteurization, whereas AB and VP were significantly different (P<0.05). Antioxidant activity after retorting was not significantly different from those of un-retorted RPs. The results of color, phytochemical content, and antioxidant activity show that CM 2 or CM 3 were considerably better than CM 1, whereas cooking method had no effect after two-step retorting. Therefore, uncomplicated cooking method such as CM 1 or CM 2 are suited for commercial production of RPs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.4
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• pp.557-566
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• 2005

In preparation of steamed foam-cakes, effects of whipping time, amount of wheat flour, and amounts of emulsifier on physical properties of the steamed foam cakes were investigated using RSM (response surface methodology). The three independent variables selected for the RSM experiment were whipping time $(X_1)$, amount of wheat flour $(X_2)$, and amounts of wheat flour $(X_2)$, and concentration of emulsifier $(X_3)$ were set for single-stage mixing, respectively. A rotatable central composite design was used for treatment arrangement. The responses from the product for loaf volume, color values and textural properties were analysed. In the analysis of variance for the foam cakes prepared by single-stage method, significant interactions were observed between independent variables (experimental factors) and physical property like loaf volume (p<0.05); textural properties like hardness, gumminess, and chewiness (p<0.05). Among independent variables, concentration of emulsifier had the most effects on physical properties while whipping time. The ordinary points in surface response showed maximal points with physical property like colorimetric b value while other properties revealed saddle points. The 3-dimensional response surface graphs of the predicted regression models displayed decreasing loaf volumes with increasing whipping times and emulsifier concentrations beyond optimum levels. The optimum conditions for best loaf volume and textural property (hardness, gummimess and chewiness) of the products selected by extracting intersectional areas of the contour maps that commonly overlapped all characteristics were; $11\~13$ min whipping time, $470\~486\;g$ amount of wheat flour, and $19\~20\;g$ emulsifier concentration, in case of single-stage method. The median values extracted from the RSM experimental results for optimum manufacturing conditions for single-stage method, i.e., 12 min whipping time, 478 g amount of wheat flour, and 20 g emulsifier concentration were empirically proven to fit the predicted levels of physical properties from the final foam cakes.

• Applied Chemistry for Engineering
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• v.29 no.3
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• pp.283-288
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• 2018

As the use of environmentally friendly and non-disease natural pigments grows, various methods for extracting natural pigments have been studied. The natural color was extracted from parsley, a vegetable ingredient containing natural dyes. Target color codes of green series of natural dyes extracted as variables #50932C (L = 55.0, a = -40.0, b = 46.0) were set with the pH and temperature of extracted natural color coordinates (of the extracted), and the quantitative intensities of natural dyes were analyzed. During the colorimetric analysis predicted by the reaction surface analysis method, a color coordinate analysis was conducted under the optimal conditions of pH 8.0 and extraction temperature of $60.9^{\circ}C$. Under these conditions, predicted figures of L, a, and b were 55.0, -36.3, and 36.8, respectively, while actual experimental ones confirmed were 69.0, -35.9, and 31.4, respectively. In these results, the theory accuracy and actual error rate were confirmed to be 73.0 and 13.8%, respectively. The theoretical optimization condition of the color difference (${\Delta}E$) was at the pH of 9.2 and extraction temperature of $55.2^{\circ}C$. Under these conditions the predicted ${\Delta}E$ figure was 12.4 while the experimental one was 13.0. The difference in color analysis showed 97.5% of the theoretical accuracy and 4.5% of the actual error rate. However, the combination of color coordinates did not represent a desired target color, but rather close to the targeted color by means of an arithmetic mean. Therefore, it can be said that when the reaction surface analysis method was applied to the natural dye extraction process, the use of color coordinates as a response value can be a better method for optimizing the dye extraction process.

• Journal of Food Hygiene and Safety
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• v.3 no.1
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• pp.7-18
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• 1988

In 1987, the level of heavy metals were determined ina total of 200 samples of 9 species of shellfish of Korea. The samples were collected at the fish. markets by 10 Public Institute of Health. The samples were whelk (Buccinum striatiBBimum), oyster (Crassostrea gigas), ark shell(Tegillarca granesa), shartnecked clam (Venerupis semidecussta), hard clam (Meretrix lusoria), top shell (Turbo cornutus), abalone (Haliotis gigantea), ark shell (Scapharea broughtonii), sea-mussel (Mytilus conuscus gould), respectively. The levels of total mercury, lead, cadmium, arsenic, copper, zinc and manganese were determined. The total mercury levels were determined by mercury analyzer using the combustion gold amalgamation method. The arsenic level were determined by spectrophotometry using colorimetric sil ver diethyldithiocarbamate method after dry ash dige8tion of the samples with magnesium oxide and magnesium nitrate. The levels of other metals were determined by inductively coupled pluma spectrophotometry after wet digestion of the samples with nitric acid and su1furic acid. The results were summerized as follows; 1. The overallranges and mean(ppm) were; Hg, ND-O.221 (0.036); Pb, 0.05-1.51 (0.37); Cd, 0.02-1.86 (0.61); As, 0.5-3.97 (1.22); Cu, 0.14-54.16 (4.93); Zn, 7.40-207.17 (30.09); Mn, 0.13-s.72 (3.40). 2. The levels of all 6 metals were found to be below the maximum permissible Iimits set by the Japan lor mercury, the Netherland for lead the Hong Kong for cadmium. The Finland for Arsenic no statutory Iimits for Zn and Mn in shellfish in any countries. 3. The results show that all the 9 species of shellfish studied, none have accumulated levels dangerous enough to pose a health problem.roblem.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.5
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• pp.443-454
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• 2008

Statement of problem: A clinically successful color match is one of the important factor to get an esthetic dental restoration. Dental shade guides are commonly used to evaluate tooth color in restorative procedure. But numerous reports have indicated that common shade guides do not provide sufficient spectral coverage of the natural tooth colors. To address issues associated with the shade guide, distinct avenues have been pursued objective spectrophotometric / colorimetric assessment. Purpose: This study compared the accuracy of tooth color selection of spectrophotometer with that of human visual determination. Three main factors were investigated, namely, the effect of light, the individual variation and the experience of the observer. Material and methods: At the first experiment, on ten patients, one operator independently selected the best matching shade to the unrestored maxillary central incisor, using a Vita Classical Shade Guide in the morning, at noon and in the afternoon. The same teeth were measured by means of a reflectance spectrophotometer. At the second experiment, on ten patients, ten operators (5 experts, 5 novices) selected and measured by the same method above at noon. At the third experiment, the results of the second experiment were divided into two groups, expert and novice, and analyzed. Results: 1. There was significant difference between visual and spectrophotometric assessment (mean ${\Delta}E$ values) in experiment 1, 2, 3 (P < .05). 2. There was no significant difference between experts and novices group, when comparing with each visual and spectrophotometric assessment (mean ${\Delta}E$ values). Conclusion: Spectrophotometer could be used to analyze the shade of natural tooth objectively. Thereby, this method offers the potential tominimize considerably the need for corrections or even remakesafter intraoral try-in of restoration. Furthermore, to achieve its advantage, both the shade-matching environment and communication between dentist and technician should be optimized with use of visual and instrumental shade-matching systems.

• The Korean Journal of Mycology
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• v.10 no.1
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• pp.33-39
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• 1982

Carpophores of ten Korean strains of Lentinus edodes (Berk.) Singer, an antitumor polysaccharide producing fungus, were extracted with 0.1N NaOH solution. The extracts were dialized for seven days in distilled water and lyophilized to produce crude polysaccharide powders. Thus obtained crude polysaccharide samples were assayed for sugar contents by colorimetric method with anthrone reagent. Among ten strains examined Lentinus edododes-DMC7 was found to be the richest strain in polysaccharide content of carpophores. By shake culture experiment for biomass production, L. edodes-DMC7 was found to be the second most productive strain among seven strains examined. Cultural characteristics of L. edodes-DMC7 were investigated by shake culture method. The best result was obtained when L. edodes-DMC7 was cultured in the medium containing glucose 8g, starch 80g, yeast extract 12g, $KH_2PO_4\;0.87g,\;MgSO_4{\cdot}7H_2O\;O.5g,\;CaCl_2\;0.3g,\;FeSO_4{\cdot}7H_2O\;10mg\;ZnSO_4{\cdot}7H_2O\;4mg,\;CuSO_4{\cdot}5H_2O\;lmg,\;MnCl_2{\cdot}4H_2O\;7mg\;per\;11\;at\;28^{\circ}C$, 180 rpm, for 12 days. Thus thirty-three grams of dry mycelia was obtained per one liter of medium.