• Journal of the Mineralogical Society of Korea
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• v.20 no.4
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• pp.357-366
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• 2007

Microorganisms participate in a variety of geochemical processes such as weathering and formation of minerals, leaching of precious metals from minerals, and cycling of organic matter The objective of this study was to investigate biogeochemical processes of iron leaching from magnetite ore by iron-reducing bacteria isolated from intertidal flat sediments, southwestern part of Korea. Microbial iron leaching experiments were performed using magnetite ore, Shinyemi magnetite ore, in well-defined media with and without bacteria at room temperature for a month. Water soluble Fe and Mn during the leaching experiments were determined by ICP analysis of bioleached samples, and the resulting precipitated solids were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The extent of iron leaching from magnetite in the aerobic conditions (Fe = 15 mg/L and Mn = 3.41 mg/L) was lower than that in the anaerobic environments (Fe = 32.8 mg/L and Mn = 5.23 mg/L). The medium pH typically decreased from 8.3 to 7.2 during a month incubation. The Eh of the initial medium decreased from +144.9 mV to -331.7 mV in aerobic environments and from -2.3 mV to -494.6 mV in anaerobic environments upon incubation with the metal reducing microorganisms. The decrease in pH is due to glucose fermentation producing organic acids and $CO_2$. The ability of bacteria to leach soluble iron from crystalline magnetite could have significant implications for biogeochemical processes in sediments where Fe(III) in magnetite represents the largest pool of electron acceptor as well as to use as a novel biotechnology for leaching precious and heavy metals from raw materials.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.12
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• pp.1535-1541
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• 2008

The aim of the present study was to investigate the antioxidant activities of methanol extracts from whole plant, flower stalk and stem of Hagocho (Prunella vulgaris). Content of total phenolic compound was the highest in flower stalk (77.1 mg/100 g) and those of others were below 54.0 mg/100 g. Flavonoid contents was the highest in stem (36.1 mg/100 g) compared to other samples. Electron donating ability of Prunella vulgaris was activated at over 70% in all samples at $500{\mu}g/mL$ concentration, especially, the activity was the highest (92.1%) in flower stalk extracts. Reducing power showed similar tendency to electron donating ability, which was significantly higher flower stalk ($0.3{\sim}1.9$), whole plant ($0.2{\sim}1.6$) and stem ($0.2{\sim}1.5$). Hydroxyl radical was scavenged over 80% in $100{\mu}g/mL$ concentration and was not significantly different between parts. Antioxidant activity in $\beta$-carotene-linoleic acid system was $47.5{\sim}84.6%$ when $1,000{\mu}g/mL$ methanol extracts was added to reaction mixtures, and flower stalk showed the highest activity. Ability of ABTs cation decolorization from Prunella vulgaris was activated over 50% in all samples when $250{\mu}g/mL$ of methanol extracts was added to reaction mixtures and $500{\mu}g/mL$ were the most suitable concentration for its activation. Nitric oxide scavenging activity was lower under 20%, but its activity was significantly higher in flower stalk than other parts. The results indicate that flower stalk from Prunella vulgaris has potent antioxidant activities.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.3
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• pp.389-396
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• 2014

The physiological properties of 70% ethanol extracts from Portulaca oleracea with different extraction methods (reflux extraction, RE; autoclave extraction, AE; low temperature high pressure extraction, LTPE) were investigated. The freeze-dried powder yields of RE, AE, and LTPE were 33.78%, 30.80%, and 11.05%, respectively. The color values of L and b were higher in LTPE, and the chroma values were higher in AE and LTPE compared to RE. The total polyphenolics and proanthocyanidin contents in LTPE were significantly higher than in other extracts. The amount of substances related to flavonoids contents was highest in RE (4.30 mg/g), followed by AE (4.06 mg/g), and LTPE (4.00 mg/g). DPPH radical scavenging ability with a concentration of 500 mg% (w/v) were in the following order; LTPE (88.87%)> RE (83.84%)> AE (80.67%). Further, the reducing power, ABTS radical scavenging ability, and nitrite scavenging activity was observed in the same tendency as seen with the DPPH radical scavenging ability. However, the ferrous ion chelating activity of RE (85.45%) and AE (83.88%) was significantly higher than that of LTPE (75.60%). ${\alpha}$-Glucosidase inhibitory activities of RE and LTPE with a concentration of 100 mg% were significantly higher than AE. Xanthine oxidase, and acetylcholinesterase inhibitory activities of LTPE were higher than the other extracts. These results suggest that the extracts from Portulaca oleracea have the potential to act as functional materials, and components of Portulaca oleracea could be effective in the prevention of Alzheimer's disease, and may be used to develop various functional food products.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.807-819
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• 2012

To evaluate the functional characteristic and availability for drinking of the fermented Smilax china leaf tea by using different microbial species, various fermented leaf tea was prepared by non-fermentation (C), or the fermentation of Saccharomyces cerevisiae (S), Bacillus sp. (B), Bifidobacterium bifidus (L), Monascus pilosus (M) and Aspergilus oryzae (A), and sensory and antioxidant parameter of each brewed tea was observed. The color of the A tea was red, but the other teas were yellow in color. Furthermore, the aesthetic quality of the A and M tea was 3.95 and 3.30 point, respectively, and other teas (2.55~2.28) were similar to that of the C tea. TP of fermented tea water extract was lower than that of the C, although TF was not significantly different between the fermented and non-fermented tea. Especially, TF of the A tea was significantly lower than those of the other teas. The range of EDA ($1mg/m{\ell}$) of water and ethanol extracts of tea C and the fermented teas was 19.25~22.48%; however, tea A was only 8.04~12.49%. In addition, FRAP, FICA and LPOIA of teas were not significantly different between the fermented and non-fermented teas. On the other hand, XOIA and AOIA of tea ethanol extracts were slightly higher than those of water extracts. XOIA of water extract derived from the teas was 4.83~9.20%, while ethanol extract of these was 9.00~19.00%. However, XOIA of B and L teas water extract was not detected. Furthermore, AOIA of fermented tea water extract (30.17~48.52%) were lower than those of ethanol extract (44.09~66.93%). In this study, interestingly, antioxidant parameters, such as FRAP, FICA, LPOIA and AOIA, of the A tea water extract (0.1%) was higher than that of the other tea in spite of high decreasing rate in the contents of TP and TF. Therefore, above results imply the possibility of fermented Smilax china leaf tea as a functional food.

• Food Science and Preservation
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• v.23 no.7
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• pp.995-1003
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• 2016

Ulmus pumila L. bark underwent distilled water extraction under three temperature condition ($4^{\circ}C$, room temperature, or $80^{\circ}C$) and two extraction times (1, or 5 min) in order to develop a functional beverage products. Changes in yield, pH, color, total phenolic (TP) content, tannin content and antioxidant activity of the aqueous extracts were evaluated for each extraction temperature and duration. Extraction conditions did not affect yield or pH value of the extracts; however CIE $b^*$ values were high in extracts prepared under high extraction temperature ($80^{\circ}C$) and long extraction duration (5 min) conditions. Both extraction temperature and duration affected the TP and tannin contents of the extracts; however, all extraction conditions resulted in ${\geq}450\;mg\;GAE/g$ TP content and ${\geq}80\;mg\;CE/g$ tannin content. All extracts exhibited ABTS and DPPH radical scavenging ability similar to that of vitamin C. Nitric oxide inhibition activity was lower in the 5 min duration sample than in the 1 min sample. The $4^{\circ}C$ extraction temperature produced an extract with the highest reducing power and hydrogen peroxide values. Extraction temperature also affected sensory evaluation results with the $80^{\circ}C$ extraction temperature producing significantly higher flavor, bitterness, and color score, than those obtained under $4^{\circ}C$ and room temperature extraction conditions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.7
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• pp.933-940
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• 2010

To confirm antioxidant activity of black garlic, methanol extract of black garlic was fractioned by hexane, chloroform, ethyl acetate, buthanol and water. Antioxidant activities of solvent fractions were assayed in 100, 250, 500 and $1,000\;{\mu}g/mL$ concentrations. The contents of total phenol and flavonoids were significantly higher 5.5~11.6 times in chloroform, ethyl acetate and hexane fraction than other fractions. Antioxidant activities of solvent fractions were increased by higher sample concentrations and their activities were significantly higher in chloroform and ethyl acetate fractions than others. DPPH radical scavenging activity was over 50% in $1,000\;{\mu}g/mL$ concentration, except butanol and water fraction. In the same concentration, reducing power was also significantly lower in butanol and water fraction. ABTS radical scavenging activity was higher in hexane, chloroform and ethyl acetate fractions and was over 70% at $1,000\;{\mu}g/mL$ concentration. In $1,000\;{\mu}g/mL$ concentration, the range of hydroxy radical scavenging activity was 50.27~81.02% and SOD-like ability was 26.73~47.64%. Antioxidant activity in linoleic acid reaction system was significantly higher when storage time was longer and sample concentration was higher in non-polar solvent fractions. Nitrite scavenging activity was relatively higher than antioxidant activity and the activity in $100\;{\mu}g/mL$ concentration was over than 50%, except butanol fraction.

• Journal of Life Science
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• v.28 no.8
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• pp.923-930
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• 2018

In this study, Tenebrio molitor (T. molitor) was fermented with Lactobacillus plantarum JBMI F3 (F3), Lactobacillus plantarum JBMI F5 (F5), Lactobacillus gasseri Ba9 (Ba9), Aspergillus kawachii KCCM 32819 (Ak), Saccharomyces cerevisiae KACC 93023 (Sc), and Bacillus subtilis KACC 91157 (Bs). After fermentation, the fermented products were extracted by water, ethanol, and methanol, and their physicochemical and biological properties were investigated. In a DPPH assay, the water extracts of the fermented products of T. molitor showed high antioxidant ability. Among the water extracts, the fermented product by Bs showed the highest DPPH radical scavenging activity. The total contents of phenolic compounds and flavonoids were highest in the fermented products by Ak and Bs, respectively. Reducing activity was detected the most high activity on ethanol extract of fermented product by Bs. The water extract of the fermented product by Bs exhibited strong enzymatic activity for fibrinogen and starch hydrolysis. Based on the observed physicochemical and biological properties, the fermented products of T. molitor by microorgansims can likely be applied as functional materials in various industries.

• Journal of Microbiology and Biotechnology
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• v.9 no.1
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• pp.22-31
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• 1999

Saccharomyces fermentati and Leuconostoc mesenteroides were isolated from a traditional kimchi, and then the Leu. mesenteroides was mutated to the acid-tolerant mutant Leu. mesenteroides M-l00. In the result of growth properties in MRS broth with various pHs adjusted with HCl and acid solution (latic acid:acetic acid=1:2), an acid-tolerant mutant Leu. mesenteroides M-100 showed more increased ability for growth than its wild strain at various temperatures. The strains were used as starters for the fermentation of kimchi. The experiments were performed with classified experimental groups (Group I, control kimchi; Group II, addition of YK-19 only; Group III, addition of M-100 only; Group IV, addition of mixture of M-100 and YK-19), and their pH, total acidity, reducing sugars content, organic acid productivity, organoleptic tests, and microfloral changes were compared. As a result, in pH and acidity, the optimal ripening period of Group IV was about 13.5 days (i.e. from the 8.5 to 22 days of fermentation). This result indicates that the optimal ripening period of Group IV was about 1.5 times longer than that of Group I. Furthermore, Group IV was edible to 28 days of fermentation. In addition, high contents of succinc acid was observed in Group IV. Group IV was also highly ranked on the organoleptic test. During the fermentation of kimchi, the number of Leuconostoc sp. in group I reduced after 7 days; however, the number of Leuconostoc sp. in Group II, III, and IV decresed after 14 days of fermentation. An especially high number of Leu. sp. was observed in Group IV, and this gave better flavor of kimchi than any other during the whole fermentation period. Citric acid, tartaric acid, succinic acid, fumaric acid, and lactic acid were detected in the kimchi, and a significant increase in the concentration of lactic acid during fermentation was observed in the all experimental groups.

• YAKHAK HOEJI
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• v.54 no.4
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• pp.258-269
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• 2010

As people are easy to access the National Health Insurance, medical health service has been increased. It contributed to extend human's average life expectancy and to get better health care. But also increased unnecessary health service or inappropriate drug use. Therefore, DUR (Drug Use Review) is needed to induce appropriate drug use. The purpose of this study is to evaluate outpatient prescriptions by General Practitioner (GP) and Specialized Practitioner, especially indication for ENT referral including common cold which is the frequent indications that have patient see doctor. This study was reviewed retrospectively prescriptions for ENT referral collected at the A pharmacy for ENT Clinic in Cheong-Ju, B pharmacy for GP Clinic in BoEun from Feb 2nd, 2009 to Feb 28th, 2009. Each pharmacy located closed to the each enrolled clinic. The numbers of collected prescriptions were each A pharmacy (n=2501), B pharmacy (n=1343). This study was classified Drug Related Problems (DRPs) those prescriptions had as total 6 groups according to following 6 categories; 1) Unnecessary Drug, 2) Wrong Drug, 3) Low Dose, 4) Overdose, 5) Wrong Instruction, 6) Wrong Combination. In results, Specialized Practitioner's prescriptions had more DRPs than General Practitioner's prescriptions (ENT 155.34% vs GP 130.01%). In detail, Specialized Practitioner's prescriptions had more DRPs in Low Dose (ENT 16.95% vs GP 4.77%), Overdose (ENT 6.72% vs G.P 5.51%), Wrong Instruction (ENT 7.91% vs GP 5.81%), Wrong Combination (ENT 29.31% vs GP 25.09%). These DRPs would be caused from lack of consideration for dosage and drug interaction. General Practitioner's prescriptions had more DRPs in Unnecessary Drug (ENT 70.37% vs GP 78.85%), Wrong drug (ENT 4.12% vs GP 9.98%). These DRPs would be associated with drug selection. This study was assumed that Specialized Practitioner is better prescriber than General Practitioner because Specialized Practitioner complete additional intern and residency training. But, Specialized Practitioner is not always better prescriber than General Practitioner. Furthermore, prescriptions of both Specialized Practitioner and General Practitioner had many problems. In conclusion, It could be cut down the excessive medical expense and expected more efficient medical care by reducing DRPs, thus contributing to the improvement of national health. In order to pharmacist must have good professional ability of pharmacotherapy to help the physician for the drug selection.

• Food Science and Preservation
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• v.17 no.1
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• pp.100-106
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• 2010

The contents and antioxidant activities of various polyphenolic fractions from commercial cocoa powder were investigated. Total phenolics extracted by 0.01 M HCl, ethyl acetate, and acidic methanol, from an 80% (v/v) methanolic extract of cocoa, were 19.25, 202.24, and 295.83 mg/g, respectively. Each fraction was capable of scavenging DPPH radicals in a concentration-dependent manner. Among the various fractions, the acidic methanol fraction had the highest ABTS radical scavenging ability. The reducing power of the 0.01 M HCl, ethyl acetate, and acidic methanol fractions were 0.44, 3.15, and 3.87, respectively, at 1,000 ${\mu}g/mL$. Antioxidant activities, as assessed by $\beta$-carotene bleaching and linoleic acid autoxidation, of the various phenolic fractions from cocoa decreased in the order acidic methanol > ethyl acetate > 0.01 M HCl. Inhibition of $\beta$-carotene bleaching mediated by the acidic methanol fraction was similar to that of the ethyl acetate fraction. The values were 60.18% and 58.97%, respectively, at 1,000 ${\mu}g/mL$. Therefore, cocoa and cocoa-containing products may contain natural antioxidants useful in prevention of diseases associated with aging.