Cher-Won Hwang

A novel function of benzyl isothiocyanate in vascular smooth muscle cells: the role of ERK1/2, cell cycle regulation, and matrix metalloproteinase-9.

Dietary isothiocyanates (ITCs) have shown protective effects against certain chemically induced cancers in animal models. These inhibitory effects are associated with reduced levels of extracellular signal‐regulated kinase (ERK) 1/2 activity and the arrest of the G1 cell cycle. Benzyl isothiocyanate (BITC) treatment down‐regulates cyclins and CDKs and up‐regulates the expression of the CDK inhibitor p21, but up‐regulation of p27 or p53 was not detected. Since antiatherogenic effects are not needed for antiproliferation, we determined whether BITC exerted inhibitory effects on matrix metalloproteinase‐9 (MMP‐9) activity in TNF‐α‐induced vascular smooth muscle cells (VSMCs). BITC inhibited TNF‐α‐induced MMP‐9 secretion in VSMC in a dose dependent manner. This inhibition was characterized by the down‐regulation of MMP‐9, which is transcriptionally regulated at the NF‐κB site, and the activation protein‐1 (AP‐1) site in the MMP‐9 promoter. These findings indicate that BITC is an effective agent for inhibiting cell proliferation, the G1 to S phase cell cycle progress, and MMP‐9 expression through the transcription factors NF‐κB and AP‐1 in TNF‐α‐induced VSMC.

Impact of bubble size on growth and CO2 uptake of Arthrospira (Spirulina) platensis KMMCC CY-007.

Optimisation of cyanobacterial cell productivity should consider the key factors light cycle and carbon source. We studied the influence of CO2 bubble size on carbon uptake and fixation, on basis of mRNA expression levels in Arthrospira platensis KMMCC CY-007 at 30°C (light intensity: 40μmolm(-2)s(-1); 1% CO2). Growth rate, carbon fixation and lipid accumulation were examined over 7days under fine bubble (FB) (100μm Ø) bulk bubble (BB) (5000μm Ø) and non-CO2 (NB) aeration. The low affinity CO2 uptake mRNA (NDH-I4 complex) was stronger expressed than the high affinity NDH-I3 complex (bicA and sbtA) under 1% CO2 and FB conditions, with no expression of bicA1 and sbtA1 after 4days. The high affinity CO2 uptake mRNA levels corresponded to biomass, carbon content and lipid accumulation, and increase in NDH-I3 complex (9.72-fold), bicA (5.69-fold), and sbtA (10.61-fold), compared to NB, or BB conditions.

Inhibitory effects of Bombusae concretio Salicea on neuronal secretion of Alzheimer's β-amyloid peptides, a neurodegenerative peptide

Alzheimers disease (AD) is characterized by the age-related deposition of β-amyloid (Aβ) 40/42 peptide aggregates in vulnerable brain regions. Multiple levels of evidence implicate a central role for Aβ in the pathophysiology of AD. Aβ is generated by the regulated cleavage of a = 700 amino acid Aβ precursor protein (βAPP). Full-length βAPP can undergo proteolytic cleavage either within the Aβ domain to generate secreted sβAPPα or at the N-terminal and C-terminal domain(s) of Aβ to generate amyloidogenic Aβ peptides. Several epidemiological studies have reported that estrogen replacement therapy protects against the development of AD in postmenopausal women. The aim of this study was to elucidate the antioxidant neuroprotective mechanism of Bombusae concretio Salicea (BC). BC was effective protectants against oxidative glutamate toxicity in the murine neuroblastoma cells (N2a) and human neuroblastoma cells (SK-N-MC). BC exhibited similar protective properties against oxidative glutamate toxicity and H2O2 toxicity. BC exhibited an antioxidant activity at approximately 20 μg/ml. BC of 5 μg/ml was ineffective in preventing the oxidative modification of LDL. The half-maximal effective concentration for BC was 16 μg/ml. These results suggested that BC supplementation in elderly men may be protective in the treatment of Alzheimers disease (AD). We report here that treatment with BC increases the secretion of the nonamyloidogenic APP fragment, sβAPPα and decreases the secretion of Aβ peptides from N2a cells and rat primary cerebrocortical neurons. These results raise the possibility that BC supplementation in elderly men may be protective in the treatment of AD.

Anti-oxidizing functional effect of polyamine as a bioconversion starter using microbes isolated from fluke babsikhae

Polyamines are well known as important molecular compounds for many biochemical processes in animals and plants. The function of biogenic polyamine has been especially well studied for its role in the oxidative system and the protection of membranes from peroxidation in cells. We investigated the polyamine contents of fluke babsikhae and isolated polyamineproducing lactic acid bacteria (LAB) to improve the probiotic antioxidative function of the Korean traditional fermented food, fluke babsikhae. In the present study, first we confirmed that fluke babsikhae possesses more antioxidative molecules compared to the other antioxidative vegetable (Korean radish) and ascorbic acid by using the method of peroxide value (POV). Secondly polyamines, which are considered as antioxidative molecules, were detected in fluke babsikhae using thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). In order to improve the probiotic function of fluke babsikhae, LABs were isolated from the fermented food, and these isolated microbes were tentatively identified as Lactobacillus brevis strain bh3 and Lactobacillus sp. using 16S rRNA sequencing. Polyamine was produced from these two strains and also was confirmed to have antioxidative activity. Especially Lactobacillus sp. was shown to produce high amounts of putrescine. Therefore, this strain can be considered as a starter to improve the probiotic function of fluke babsikhae. According to the results, fluke babsikhae will be a good candidate for a healthy functional food and also isolated LAB will be considered as a starter for probiotics by bioconversion.

Influences of Addition of Jellyfish Powder to Bed Soil and Bacterial Community Structure of Bed Soil

Recently, the population of toxic and/or unusable jellyfish is increasing during summer along the east coast of Korea, causing massive economical and ecological damage to fisheries, nuclear power plant and marine environment. To solve this problem, this study was carried out using jellyfish as a potential soil additive for horticulture. The jellyfish was solidified and homogenized, then mixed with a commercial bed soil. Allium tuberosum ROTH was planted to control bed soil (BS) and jellyfish powder mixed bed soil groups (Mixed bed soil, MBS), and following parameters were measured during five weeks: water content, electrical conductivity and growth of leaves. At the end of the experiment, bacterial community structures of each pot were analyzed by DGGE. The relative water adsorption of jellyfish powder was about 2.5 times greater compared to its dry weight. The water content of MBS group was significantly higher than BS group 6.5 to 14.2%, and the electric conductivity of MBS group was measured around 2.8 dS/m where BS group was resulted average of 1.8 dS/m. However, the leaves of BS group were grown 30% longer compared to MBS group. DGGE analysis of MBS group was shown in high number of phylum Bacteroidetes and increased diversity of Sphingobacteriia compared to BS group. Jellyfish powder as a soil additive surely will be a good candidate as humectant and microbiota stimulator, although there are several obstacles such as high electrical conductivity and residual alum salt which used for solidification of jellyfish.

Antibacterial effects of extracts of Thuja orientalis cv Aurea Nana cones against food-spoilage and food-borne pathogens

BACKGROUND: Nowadays, Chemical antiseptics have become great problems for health and environmental, so that developing of new substitutes for chemical antiseptics is more and more important. Natural product is a kind of environment-friendly additive that could be used as antiseptic in food industry. Thuja orientalis cv Aurea Nana is a gymnospermous plant of the family Cupressaceae, native to northwestern China and widely naturalised elsewhere in Korea and Japan. This study was aimed to investigate the antibacterial potential of various organic extracts from T. orientalis cones against some food-borne and food-spoilage bacteria. METHODS AND RESULTS: Hexane extract (HE), chloroform extract (CE), ethyl acetate extract (EAE) and methanol extract (ME) were obtained from female cones of T. orientalis. The antibacterial activities of various extracts were tested by standard agar diffusion and minimum inhibitory concentrations (MICs) against five gram-positive and six gram-negative bacteria. Cell viability and morphology change of L. monocytogenes ATCC 10943 treated with hexane extract were also observed. The various extracts displayed remarkable antibacterial effects against all the gram-positive bacteria but did not show any effect against the gram-negative bacteria. Hexane extract has the highest inhibitory effect on cell viability of L. monocytogenes ATCC 10943. SEM observation also demonstrated the damaging effect of the hexane extract on the morphology of L. monocytogenes ATCC 10943 at the minimum inhibitory concentration. CONCLUSION(s): The tested gram-positive bacteria were significantly inhibited by organic extracts of T. orientalis cone. Hexane extract was the most potent against Listeria monocytogenes ATCC 10943, as evidenced by the lowest MIC level and the complete inhibition of cell viability within shortest exposure time, along with SEM observation.

Characterization and Antifungal Activity from Soilborne Streptomyces sp. AM50 towards Major Plant Pathogens

BACKGROUND: Chemical fungicides not only may pollute the ecosystem but also can be environmentally hazardous, as the chemicals accumulate in soil. Biological control is a frequently-used environment-friendly alternative to chemical pesticides in phytopathogen management. However, the use of microbial products as fungicides has limitations. This study isolated and characterized a three-antifungal-enzyme (chitinase, cellulase, and β-1,3-glucanase)-producing bacterium, and examined the conditions required to optimize the production of the antifungal enzymes. METHOD AND RESULTS: The antifungal enzymes chitinase, cellulase, and β-1,3-glucanase were produced by bacteria isolated from an sawmill in Korea. Based on the 16S ribosomal DNA sequence analysis, the bacterial strain AM50 was identical to Streptomyces sp. And their antifungal activity was optimized when Streptomyces sp. AM50 was grown aerobically in a medium composed of 0.4% chitin, 0.4% starch, 0.2% ammonium sulfate, 0.11% Na2HPO4, 0.07% KH2PO4, 0.0001% MgSO4, and 0.0001% MnSO4 at 30℃. A culture broth of Streptomyces sp. AM50 showed antifungal activity towards the hyphae of plant pathogenic fungi, including hyphae swelling and lysis in P. capsici, factors that may contribute to its suppression of plant pathogenic fungi.