• Journal of Life Science
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• v.25 no.2
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• pp.180-188
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• 2015

The bacterial strain isolated from Kimchi showed antibacterial activity against Micrococcus luteus IAM 1056. The selected strain was identified as Lactococcus lactis by 16S rRNA nucleotide sequence analysis and named as Lactococcus sp. KD 28. The treatment of culture supernatant with proteinase K removed antibacterial activity, indicating its proteinaceous nature, a bacteriocin. This bacteriocin was sensitive to hydrolytic enzymes such as ${\alpha}$-chymotrypsion, trypsin, proteinase K, lipase, ${\alpha}$-amylase and subtilisin A. The bacteriocin was highly thermostable and resistant to heating at $80^{\circ}C$ for up to an hour but 50 % of the total activity was remained at $100^{\circ}C$ for 30 min. The pH range from 2.0 to 8.0 had no effect on bacteriocin activity and it was not affected by solvents such as acetonitrile, isopropanol, methanol, chloroform and acetone up to 50% concentration. The bacteriocin showed antibacterial activity against M. luteus IAM 1056, Lactobacillus delbrueckii subsp. lactis KCTC 1058, Enterococcus faecium KCTC 3095, Bacillus cereus KCTC 1013, B. subtilis KCTC 1023, Listeria ivanovii subsp. ivanovii KCTC 3444, Staphylococcus aureus subsp. aureus KCTC 1916, B. megaterium KCTC 1098 and B. sphaericus KCTC 1184. The bacteriocin was purified through ammonium sulfate concentration, SP-Sepharose chromatography and RP-HPLC. The molecular weight was estimated to be about 3.4 kDa by tricine-SDS-PAGE analysis.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.303-309
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• 2003

This study was performed to investigate the antimutagenic and antioxidative activities of pine pollen with respect to the microbial mutation induced by various mutagens such as 1-NP, daunomycin, 2-NF, MNNG, NaN$_3$, 4NQO, 4-NOPD, AFB$_1$, Trp-P-1, 2-AF and oxidative mutagens such as t-BOOH, H$_2$O$_2$. Pine pollen, originally extracted with hexane, was reextracted with 70% methanol. The results obtained using the methanol extract, in terms of the antimutagenicity observed in relation to ten kinds of mutagens, showed that it exhibited 17.8, 82.2 and 80.9% inhibitory effects against daunomycin, AFB$_1$, and Trp-P-1, respectively, in Salmonella. typhimurium TA98 and a 72.3% inhibitory effect against AFB$_1$in S. tyPhimurium TA100. In terms of the antimutagenicity exhibited in relation to t-BOOH, a 72.3% inhibitory effect was observed, but no antimutagenicity was observed in relation to the other mutagens and strains. The methanol extract was further fractionated by chloroform, ethyl acetate, n-butanol. In S. typhimurium TA98, the chloroform(150 $\mu\textrm{g}$/plate) fraction showed strong antimutagenic effects of 55.6%, 93.7% and 93.5%, while the ethyl acetate(100 $\mu\textrm{g}$/plate) fraction showed 11.4%, 74.3% and 85.2% in relation to the mutagenicity induced by daunomycin, AFB$_1$and Trp-P-1, respectively. In S. typhimurium TA100, the chloroform and ethyl acetate fractions showed antimutagenic effects of 95.1% and 62.5%, respectively, on the mutagenicity induced by AFB$_1$. In S. typhimurium TA102, the chloroform fraction showed an antimutagenic effect of 93.6% on the mutagenicity induced by t-BOOH.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.464-470
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• 1994

The biological activities of Humulus japonicus were extracted by water and methanol. Methanol was better solvent than water in the extraction for antimicrobial activities against six different species of bacteria and two yeasts. The methanol extract was systematically fractionated with various organic solvents which have different polarities. From the result of antimicrobial activities against six species of bacteria and two species of yeasts, methanol extract was superior to water extract. The methanol extract of Humulus japonicus showed antimicrobial activity against the all species of microorganisms tested except Escherichia coli . The butanol fraction of methanol extract showed antimicrobial effect on the all species tested. The minimal inhibition concentration(MIC) of the butanol fraction on the growth of microorganisms was ranged between $0.1{\sim}0.4%$. The water extract of Humulus japonicus did not show inhibition of the activity of trypsin but methanol extract showed inhibitory activity. The chloroform fraction of methanol extract showed comparatively higher trypsin inhibitory activity than other fractions. The concentration of 50% inhibition$(IC_{50})$ by chloroform fraction was 1.0 mg/ml. Enzyme-inhibitor complex formation was above 90% of the while for 20 min. It was revealed that methanol extract of Humulus japonicus inhibited peroxide production of lard and soybean oil as substrate by antioxidative test. The chloroform fraction of methanol extract had the highest activity. When 0.2% of chloroform fraction was added, induction period of soybean oil and lard were extended 15, 9 days, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.6
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• pp.693-700
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• 1992

As an approach to study a new natural antioxidant for edible fats and oils, antioxidative fractions from acorn powder were characterized. The oxidative stabilities of soybean, palm, beef tallow, and lard oil containing the acorn active fraction extracted with various organic solvents were studied by determining the peroxide value during the storage at $60^{\circ}C.$ And this effective antioxidative components were isolated and identified by thin layer chromatography and high performance liquid chromatography. The proximate compositions of acorn powder were water 11.9~12.0%, protein 7.1~7.4%, starch 65.5~69.4%, fat 2.1~2.6%, fiber 2.1~3.6%, ash 2.4~2.6%, and total tannin 4.6~6.8%, respectively. The final yield of fraction extracted by sequential order of acetone : $H_2O$(1 : 1) and ethylacetate was 2.8~3.1%. Gallic acid, digallic acid and gallotannin were contained this final fraction. The main antioxidative activity was speculated due to the presence of gallic acid in acorn powder extract. The antioxidative activity was more effective in fat water emulsion than just fat system. Antioxidative activities measured by peroxide value were quite high in beef tallow and soybean emulsion, but low in lard and palm oil emulsion in the concentration of 200ppm acorn extract. Therefore, the addition of 200ppm acorn extract was suggested to expect effective antioxidation concentration in the reaction system.

• Applied Biological Chemistry
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• v.41 no.5
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• pp.390-394
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• 1998

The tuber of Liriope platyphylla was extracted with 80% aqueous MeOH and solvent-fractionated with EtOAc, n-BuOH and $H_2O$. Evaluation of growth inhibitory activity of each fractions on various carcinoma cells, A549, SK-OV-3, SK-Mel-2, XF-498 and HCT-15, indicated the n-BuOH fraction to be the highest in the activity. From the fraction, two saponin compounds were isolated through Amberlite XAD-II and silica gel column chromatographies, repeatedly, and their chemical structures were elucidated as spicatoside A and B by interpretation of spectral data, NMR and IR, and adaptation of acid hydrolysis. Spicatoside A showed growth inhibitory activity on carcinoma cells, and the $IC_{50}$ values against A549, SK-OV-3, SK-Mel-2, XF-498 and HCT-15 cells were determined to be 17.3, 21.7, 14.9, 18.8 and $15.6\;{\mu}g/ml$, respectively.

• Microbiology and Biotechnology Letters
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• v.39 no.3
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• pp.238-244
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• 2011

Biodiesel, mono-alkyl esters of long chain fatty acids, is one of the alternative fuels derived from renewable lipid feedstock, such as vegetable oils or animal fats. For decade, various lipases have been used for the production of biodiesel. However, the production of biodiesel by enzymatic catalyst has profound restriction in industry application due to high cost. To overcome these problems, many research groups have studied extensively on the selection of cheap oil sources, the screening of suitable lipases, and development of lipase immobilization methods. In this study, we produced biodiesel from plant oil using Proteus vulgaris lipase K80 expressed in Escherichia coli cells. The recombinant lipase K80 was not only expressed in high level but also had high specific lipase activity and high stability in various organic solvents. Lipase K80 could produce biodiesel from olive oil by 3-stepwise methanol feeding method. The immobilized lipase K80 also produced biodiesel using the same 3-stepwise method. The immobilized lipase could produce biodiesel efficiently from various plant oils and waste oils.

• Microbiology and Biotechnology Letters
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• v.38 no.4
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• pp.428-433
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• 2010

Enzymatic hydrolysis of sulfate groups in agaropectin or agar simplifies the production process of high-quality or low sulfate-content agarose. This study was investigated that cell surface displayed arylsulfatase can be applied to desulfatation of agar for production of agarose. Sulfate content of agarose prepared by treatment of yeast surface-displayed arylsulfatase was decreased in a enzyme dosedependent manner. Especially, 35 unit/mL of yeast surface arylsulfatase attenuated sulfate content of agarose up to 0.2%. In the 0.6% agar(Junsei), 35 unit/mL enzyme treated at $40^{\circ}C$ for 3 h showed the lowest content of sulfate. Therefore, this result was determined to be the optimal condition to desulfatation of agar for production of agarose. In addition, the gel strength of yeast surface arylsulfatase treated agar and commercial agarose were compared. Agarose prepared by treatment of yeast surface arylsulfatase showed $559.8{\pm}0.12$ of gel strength, and it is a similar compared to the commercial agarose.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.108-112
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• 2005

Antimicrobial and antitumor activities of Camellia sinensis L seed extracts were investigated. Seed extracts showed antifungal activities against Candida albicans IFO 1594 and Cryptococcus neoformans. Inhibition zone of 20 mm was shown by 70% ethanol extract against C. albicans IFO 1594 at 100 mg/mL. Antifungal activity of seed extract was not decreased by heating at 80 and $100^{\circ}C$ for 30 min or at $121^{\circ}C$ for 15 min, indicating heat-stability of seed component. Growth-inhibitory effects were observed in 70 and 10% of tumor cell line SK-OV-3 and normal ceil line NIH/3T3 at $50{\mu}g/mL$, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.42-47
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• 2008

Prevention of postprandial hyperglycemia is important, as it is implicated in the development of macro- and microvascular complications associated with diabetes. An inhibitor of ${\alpha}$-amylase which acts in the first step of carbohydrate digestion, is expected to be a suppressor of postprandial hyperglycemia. This study investigated the porcine pancreatic ${\alpha}$-amylase inhibitory activity of the extracts from buckwheat (Fagopyrum esculentum) flower, leaf, stem and grain. Flower, leaf, stem and grain of buckwheat were extracted by water and ethanol (40%, 70%, 100%), respectively. Flower and leaf extracts were more effective ${\alpha}$-amylase inhibitors than stem and grain extracts in all tested solutions. Ethanol extracts were more effective than water extracts or powders on the ${\alpha}$-amylase inhibitory activities. At concentrations of $0.5%{\sim}10%$ (w/w, starch basis), the flower extracts of 40%, 70% and 100% ethanol lowered the enzyme activity by about 90% and the results were similar to the values of acarbose. At the same concentrations, the leaf extracts of 100% ethanol lowered the enzyme activity by about 90%. These results suggest that buckwheat flower and leaf ethanol extracts may delay carbohydrate digestion and lower postprandial hyperglycemia.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.819-824
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• 2007

The present study describes the cytotoxic effect of Artemisia fukudo extracts. The extract from A. fukudo by 80% ethanol was fractionated with n-hexane, dichloromethane, ethylacetate, and butanol in serial. The cytotoxicity of A. fukudo extracts was examined for its effect on the growth of HL-60 cells by the colorimetric 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assay. In addition, we used the HL-60 cells to see what effects the A. fukudo extracts will have on apoptosis of cancer cells. We checked the cell activity, cell morphologic changes, DNA fragmentation, and DNA content after 24 hr incubation with administering 25 ${\mu}g/mL$ of the A. fukudo extracts. In the treatment of the low concentration of n-hexane and dichloromethane fractions, the survival rate of HL-60 cells is lower than that of the control. The laddering-pattern DNA fragmentation was observed in the treatment with n-hexane and dichloromethane fractions. The DNA content of the cells apoptosis measured as the density of sub-$G_{1}$ hypodiploid cells by flow cytometric analysis. The number of sub-$G_{1}$ hypodiploid cells increased in the treatment with n-hexane and dichloromethane fractions. These fractions obstructed the cell cohesion and caused the blebbing of the cell membrane and fragmentation of the nucleus, both of which are symptoms of apoptosis. These results suggest that A. fukudo has a great potential value as food additives, medicinal supplements for patients with chronic diseases, and preventive measures against cancer.