• Journal of Life Science
• /
• v.17 no.11
• /
• pp.1601-1604
• /
• 2007

The gene for ${\beta}-agarase$ of an Agarivorans sp. JA-1 was expressed in Bacillus subtilis DB104, 168 and ISW1214 strains for mass-production. Among 3 host strains, B. subtilis ISW1214 secreted the highest amount of recombinant ${\beta}-agarase$ with a specific activity of 201 U/mg and 360 mg of protein into culture broth. This was approximately 130-fold higher than the production in E. coli as an expression host. Recombinant enzyme produced neoagarooligosaccharides such as neoagarohexaose, neoagarotetraose, and neoagarobiose from agar. Produced neoagarooligosaccharides showed antibacterial activities against gram-negative E. coli and gram-positive B. subtilis at a concentration of 1.5%. These data suggest that neoagarooligosaccharides could be an useful preservative for food industry.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.7
• /
• pp.2522-2527
• /
• 2010

The aim of this study was to investigate the tyrosinase inhibitory activity and antimicrobial activity by mixtures of ultrasonicated chitosan and Maillard reaction products. Analysis of tyrosinase was purified from potato and confirmed by active staining after SDS-PAGE. Maillard reaction products (MRPs) were formed from various sugars (glucose, fructose, galactose, xylose, arabinose or ribose) and cystein. MRPs inhibited the tyrosinase purified from potato. The highest tyrosinase inhibitory activity was shown by MRP from glucose and cystein. Ultrasonicated chitosan (over 1 hr) showed antimicrobial activity at the concentration of 1% against E. coli and S. aureus. For the development of antibrowning agent with antimicrobial activity, tyrosinase inhibitory and antimicrobial activity by the mixtures of ultrasonicated chitosan and MRP were tested. 1:1 mixture of ultrasonicated chitosan and MRP from glucose and cystein was the best antibrowning agent having antimicrobial activity.

• Journal of the Korean Applied Science and Technology
• /
• v.32 no.1
• /
• pp.108-115
• /
• 2015

Vinca alkaloid compounds including vincamine from Vinca minor L. have been extracted by ethanol and hot water extraction methods. Antimicrobial properties of those extracts have been investigated against dandruff causing microorganism Malassezia furfur, yeast, Gram positive and negative bacteria. Vincamine standard and ethanol extract showed no sign of antimicrobial activity, whereas hot-water extract had the activity against M. furfur. Furthermore hot water extract had antimicrobial activity against Gram positive Bacillus sp. and Gram negative Escherichia coli. Cytotoxic properties of those extracts have also been investigated with HaCaT cell (human keratinocyte), HT-29 cell (human colorectal adenocarcinoma cell) and Raw cell, showing no significant cytotoxic effects. We also measured the ROS using dichlorofluorescein diacetate (DCFDA), a popular fluorescence-based probe for reactive oxygen species detection. The result showed the increasement of reactive oxygen species formation (20%) in HaCaT and HT-29 cell lines.

• KSBB Journal
• /
• v.23 no.2
• /
• pp.158-163
• /
• 2008

In this study, we have investigated the antibacterial, antioxidant, and antitumor activities of mycelium cultural extract from mushroom. Mushroom mycelium was grown in a synthetic liquid media such as PD broth, YM broth or citrus extracts. In antibacterial activity test, the best result was achieved when mycelium cultural extracts from Phellinus linteus and Coriolus versicolor were incubated together on YM broth. On the other hand, mushroom mycelium cultured on citrus extracts showed better activity than that on PD broth. We have also tested the antioxidant activity at concentration up to 10 mg of mycelium cultural extract/mL. The more it is in higher concentration, the more the activity increases. The higher antioxidant activity was observed both on PD broth containing the Phellinus linteus and Coriolus versicolor mycelium and citrus extract containing the same. The complex culture extracts obtained from the synthetic medium and citrus extract medium showed 10-89% of the 1,1-diphenyl-2-picrylhydrazyl radical scavenger activity. The antitumor activity of mycelium cultural extract was examined by using MTT assay on A549 cells. Mushroom mycelium cultured on citrus extracts showed interestingly higher antitumor activity than that on synthetic liquid media.

• Journal of Life Science
• /
• v.27 no.6
• /
• pp.646-651
• /
• 2017

This study was carried out to examine the antimicrobial activity of 70% ethanol and hot water extracts from different parts and essential oil in Pinus densiflora on skin pathogens such as Staphylococcus epiermidis, S. aureus, Propionibacterium acnes, Candida albicans, C. tropicalis, and Trichophyton rubrum. The antimicrobial activities of extracts and essential oil were tested by paper disc assay and minimum inhibitory concentration test. The ethanol extract of pine pollen showed antimicrobial activity against C. tropicalis and T. rubrum. Ethanol extract of pine needle and pine gnarl showed antimicrobial activity against S. aureus, C. tropicalis, and P. acnes. Essential oil from pine needle exhibited antimicrobial activity against C. albicans, C. tropicalis, and P. acnes. The minimum inhibitory concentration of ethanol extracts of pine needle and pine gnarl against P. acnes and C. tropicalis ranged from 0.002% to 0.0063%. The lowest minimum inhibitory concentration (0.025%) against C. albicans and C. tropicalis was obtained from essential oil. These results indicate that ethanol extracts of pine pollen, pine needle, pine gnarl, and essential oil of pine needle could be applicable to control the skin infection pathogens. Especially, ethanol extract of pine gnarl had a broad spectrum of antimicrobial activity and pine extracts and essential oil exhibited higher antimicrobial activity with Candida sp. and P acnes.

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

• The Korean Journal of Mycology
• /
• v.34 no.2
• /
• pp.92-97
• /
• 2006

The liquid culture extract of Coriolus versicolor was prepared by directly boiling the whole culture broth 7 days after incubation in 12% citrus extract medium. After removal of mycelial debris through filtration, this extract was further extracted with equal volume of ethyl acetate (1 : 1, v/v). The ethyl acetate extracts showed significant antibacterial activities against Stapylococcus aureus CCARM3230 and Psudomonas aeruginosa CCARM2171, which are resistant to several antibiotics. The most active fraction was eluted from a silica gel column with a mixture of dichloromethane and methanol (9 : 1, v/v) and the purity of this active substance was confirmed by HPLC analysis. The results suggest that the purified active substance could be a good source for the development of a new antimicrobial agent, especially for the treatment of antibiotic resistant bacteria.

• Journal of Life Science
• /
• v.27 no.6
• /
• pp.611-616
• /
• 2017

The antibacterial activities of nine oriental herbal medicine extracts were measured against seven kinds of bacteria known to cause food poisoning and disease. The extracts were prepared with distilled water using an autoclave ($121^{\circ}C$ for 30 min). The extraction yields of nine oriental herbal medicines were in the rage of 0.5%-33.4%. The antibacterial activities were evaluated using the paper-disc method. Extracts of Hwangryeon, Jiyu, and Ohbaeja showed antibacterial activities while the others did not. Extracts of Coptis japonica, Hwangryeon, and Sanguisorba officinalis, Jiyu showed antibacterial activities only against Clostridium perfringens and Listeria monocytogenes. Extracts of Rhus javanica, Ohbaeja showed the strongest antibacterial activities against all the bacteria tested. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of R. javanica extracts were in the range of 2.4~20 mg/ml for the bacteria tested. In conclusion, the extract of R. javanica showed superior antibacterial activities against the seven bacterial strains tested. The MIC and MBC values for each bacterium were represented as strain names (MIC, MBC), which were Bacillus cereus (11.2, 20), Clostridium perfringens (2.4, 4.7), Escherichia coli (9.1, 9.1), Listeria monocytogenes (11.1, 20), Salmonella typhi (4.7, 9.1), Staphylococcus aureus (2.4, 4.7), and Vibrio parahaemolyticus (2.4, 5.3). Further purification and study of this antibacterial material would be helpful for developing antibiotics or promoting synergistic effects with known antibiotics, producing antibacterial material for lengthening the shelf-life of food, and so on.

• Journal of Life Science
• /
• v.25 no.12
• /
• pp.1399-1407
• /
• 2015

Klebsiella pneumoniae is found in the normal flora of the skin, mouth, respiratory tract, urinary tract, and intestines in human. However, the stain is opportunistic pathogen, which is the causative agent of community acquired pneumonia. Corn silk has been known to be effective for antimicrobial activity against pathogenic bacteria, including K. pneumoniae, Staphylococcus aureus, Bacillus subtilis, Shigella spp., Salmonella spp., Escherichia coli, Pseudomonas aeruginosa, et al. In this study we focused on the antimicrobial properties of con silk water extract of K. penumoniae. K. pneumoniae isolates K. pneumoniae ATCC 13883 and broad-spectrum β-lactamase (BSBL), exteded-spectrum β-lactamase (ESBL), carbapenemase-producers. Antimicrobial susceptibilities were determined by the disk diffusion method. Searches for bla genes were performed by PCR amplication and direct sequencing. MacConkey agar plate medium was prepared using the corn silk extracts (50% or 100%) instead of distilled water for antimicrobial activity test. The microbial growth inhibitory potential of K. pneumoniae was determined by using the MacConkey agar plate spreading method, and the plate was incubated 18 hr at 37℃. Genes encoding β-lactamases including SHV-1 (n=8), SHV-2a (n=8), SHV-5 (n=2), SHV-11 (n=2), SHV-12 (n=18), TEM-1 (n=10), CTX-M-3 (n=2), CTX-M-14 (n=2), CTX-M-15 (n=1), GES-5 (n=5), KPC-2 (n=6), KPC-3 (n=4), and NDM-1 (n=2) were detected. The corn silk extract showed significantly antimicrobial activity against K. pneumoniae ATCC 13883, but BSBLs, ESBLs, and carbapenemase producers were not. Therefore, corn silk extract is thought to be able to assist in the prevention and rapid recovery of infectious disease caused by K. pneumoniae.

• Journal of Life Science
• /
• v.18 no.6
• /
• pp.776-781
• /
• 2008

To develop natural food preservatives, methanol and water extracts were prepared from the Suaeda maritima and their antibacterial activities were examined against 12 microorganisms which were food borne pathogens bacteria, food poisoning microorganisms and food-related bacteria. Methanol extracts exhibited antibacterial activities for the 5 Gram positve and 7 Gram negative bacteria by agar diffusion method, The antibacterial activities and cell growth inhibition were investigated on each strain with the different concentrations of Suaeda maritima extracts. Antibacterial activities were shown in root, stem, furit extracts of Suaeda maritima. However stem and fruit extracts showed weak antibacterial activity against the tested microorganisms. Root extracts showed the highest antibacterial activities against microorganisms tested, such as Bacillus cereus,Bacillus subtilis, Vibrio parahaemolyticus, Staphylococcus aureus. The highest antibacterial activity against bacteria test was found in the methanol extract.