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Hamcho(Salicornia herbacea L.) reportedly contains high contents of natural minerals and dietary fibers. In recent years, Hamcho has been reported to possess many biological and pharmacological effects, including antidiabetic, hypocholesterolemic, hypolipidemic activities. In our study, obesity-suppressing effect of S. herbacea L. was investigated using 3T3-L1 adipocytes culture. The intracellula lipid droplets were stained with oil red o dye and quantificated by compareing with the control. Lipid accumulation was significantly decreased by 23.5% at the concentration of 500ug/mL. This result suggests that extracts of S. herbacea L. may have an inhibitory role on the early stage of 3T3-L1 cell differentiation and be useful source as a natural anti-obesity agent. In vivo experiment, the effects of S. herbacea L. on the reduction of body weight and the improvement of serum lipid profile in obesity-induced rats were investigated. The administration of S. herbacea L. fed with high-fat diet significantly decreased body weight gain and reduced serum lipid levels. Taken together, these results suggest that S. herbacea L. may have an inhibitory role in obesity in vitro and vivo. It may be the useful source as a natural anti-obesity agent.

Pantoea ananatis carotenoid (PAC) is β-carotene biosynthesis gene. β -carotene is a carotenoid substance naturally found in plants that serves as an accessory to photosynthesis. It is primarily responsible for the pigment in orange colored fruits and vegetables, but also contributes to the pigment in red, yellow, and green colored fruits and vegetables. To express the PAC gene (2.95 kb) in Pleurotus eryngii, pPEV-PAC, which contains the CaMV 35S promoter, PAC gene, and nos terminator, was constructed and introduced into P. eryngii via Agrobacterium tumefaciens-mediated transformation. The correct integration of PAC gene in the genome of transgenic mycelium was confirmed by PCR amplification and sequencing. We also confirmed the transcriptional level of PAC gene for 1st and 2nd generation by RT-PCR. The mycelium harboring pPEV-PAC was grown at 25℃ for 7 days in mushroom complete medium and transferred on sawdust medium (sawdust and rice bran, 2:1) to induce fruiting body of P. eryngii under LED light (blue). Color variation of P. eryngii was observed on the gill of cultivated fruiting bodies. β-carotene levels in the fruit bodies were increased to approximately 2-fold than the control. Finally, we developed a new strain of P. eryngii with phenotypic expression of β-carotene. Accordingly, this system can be used for breeding new functional mushroom and the defensive, intellectual property for genetically modified organism (GMO) will be secured.

Acetaminophen (APAP; paracetamol) is widely used as an antipyretic and analgesic, and that in high doses can result in extensive liver injury. The protective effects of an aqueous extract from the fruits of a Stauntonia hexaphylla (S. hexaphylla) on acetaminophen (APAP)-induced hepatotoxicities and the possible protective mechanisms involved were investigated in mice. Pretreatment with an aqueous extracts from fruits of S. hexaphylla (AEFSH) prior to the administration of APAP significantly prevented the increase in serum alanine aminotransferase and aspartate aminotransferase activity and hepatic lipid peroxidation in a dose-dependent manner. APAP-induced hepatotoxicity was also essentially prevented as evidenced by liver histopathology. Hepatic glutathione levels and glutathione-S-transferase activities were not affected by treatment with AEFSH alone, but pretreatment with CK protected the APAP-induced depletion of hepatic glutathione levels. The effects of CK on cytochrome P450 (P450) 2E1, the major isozyme involved in APAP bioactivation, were investigated. In microsomal incubations, AEFSH effectively inhibited the P450 2E1-dependent p-nitrophenol and aniline hydroxylase. These results indicate that the protective effects of S. hexaphylla against the APAP-induced hepatotoxicity may, at least in part, be due to its ability to block P450-mediated APAP bioactivation.

‘imchi’is a fermented food in Korea. Distinctive flavors and colors in every province of Korea can vary the nutrients as well as amino acids, minerals, and vitamins lacking in the hulled rice particularly. However, functional nutritional ingredients abundant in Kimch are not identified. General Kimchi and mushroom Kimchi with different 7 species mushroom extracts were investigated in this study. Kimchi extracts by syringe (25 mm, 45 micron) filtration were examined for mouse spleen, lymphocytes cells, cell proliferation assay (MTT assay), cell death analysis (apoptosis analysis), and gene expression analysis (Real Time PCR). It is reported that mushroom Kimchi affected the proliferation of mouse spleen cells than that of conventional Kimchi. Along with that, our findings showed that mushroom Kimchi inhibited the proliferation of cervical cancer cell (Caski) and breast cancer cell (MCF7) through the MTT assay. For analysis of cell death caused by the mushrooms Kimchi, early apoptosis cells increased. Anticancer effect by mushroom Kimchi extract resulted in the expression of genes identified p53, caspase 3,8,9, compared to control experiments. Acknowledgement This research was financially supported by the Ministry of Education, Science Technology (MEST) and Korea Industrial Technology Foundation (KOTEF) through the Human Resource Training Project for Regional Innovation (2010).

Edible bird's nest (EBN), made from the salivary excretions of the swiftlet, is one of the widely used health foods in asian communities. Until now, although EBN has been known to have immune-boosting and anti-viral activities, other functions have not been reported. This study is aimed to investigate the effects of EBN on proliferation of human adipose-derived stem cells (hADSCs) and its action mechanism. We found that EBN strongly promoted proliferation of hADSCs and nomal human fibroblasts (NHFs). Additionally, attempts to elucidate a possible mechanism underlying the EBN-mediated effects reveald that EBN induced production of IL-6 and VEGF, and that this was mediated through activation of NF-kB. Specially, WE found that production of IL-6 and VEGF was induced by EBN. In addition, EBN-induced production of IL-6 and VEGF was inhibited by PD98059, a p44/42 MAPK inhibitors, SB203580, a p38 MAPK inhibitor, and PDTC, a NF-kB inhibitor, but not SP600125, a JNK inhibitor. Similar to this, EBN-induced proliferation of hADSCs was also attenuated by PD98059, SB203580 and PDTC, but not SP600125. Taken together, these findings suggest that the EBN-induced proliferation of hADSCs primarily occurs through the increased expression of IL-6 and VEGF, which is mediated by the activation of NF-kB.

Shiitake mushroom (Lentinus edodes) is one of the most popular edible mushrooms in Korea, Japan, and China which are used as food. Especially Lenthionine can be considered as a anti-tumor candidate. In this study, the effect of mushroom of shiitake mushroom on the increase of immune activity and disease resistance of mice inoculated with pathogenic bacteria. Control group was of powder feed dose of 200 mg, group 1 of feed powder dose of 198 mg with 2 mg mushroom powder, and group 2 with 6 mg mushroom powder and 194 mg feed powder. The diet was supplemented with 120 ml tap water and made the powder a mix. It did not change the difference in weight compared to the control group that the total number of leukocytes increased significantly (P <0.05) also increased the total blood cell count (P <0.01). Total bacteria and inflammatory cells in bronchial washing and bronchial lymph nodes reduce and the number of CD3 and CD4 percentage of the total number of cells increased. Bronchial lymph nodes in the expression levels of inflammatory cytokines IFN-gamma compared with the control group 2 was significantly reduced and TNF-alpha was tended to decrease but not statistically significant.

‘imchi’is a fermented food in Korea. Distinctive flavors and colors in every province of Korea can vary the nutrients as well as amino acids, minerals, and vitamins lacking in the hulled rice particularly. However, functional nutritional ingredients abundant in Kimch are not identified. General Kimchi and mushroom Kimchi with different 7 species mushroom extracts were investigated in this study. Kimchi extracts by syringe (25 mm, 45 micron) filtration were examined for mouse spleen, lymphocytes cells, cell proliferation assay (MTT assay), cell death analysis (apoptosis analysis), and gene expression analysis (Real Time PCR). It is reported that mushroom Kimchi affected the proliferation of mouse spleen cells than that of conventional Kimchi. Along with that, our findings showed that mushroom Kimchi inhibited the proliferation of cervical cancer cell (Caski) and breast cancer cell (MCF7) through the MTT assay. For analysis of cell death caused by the mushrooms Kimchi, early apoptosis cells increased. Anticancer effect by mushroom Kimchi extract resulted in the expression of genes identified p53, caspase 3,8,9, compared to control experiments. Acknowledgement This research was financially supported by the Ministry of Education, Science Technology (MEST) and Korea Industrial Technology Foundation (KOTEF) through the Human Resource Training Project for Regional Innovation (2010).

Mushroom has been reported in the antitumor activity, antioxidant, and immune system health, thanks to a wide range of pharmacological and medicinal herbs as β-glucan (polysaccharide) up to recent year. Herein we studied for seven species of mushrooms on the immune stimulation. Mushroom extracts combined with the seven species were collected by hot water extraction. The effects of immune and disease resistance were evaluated in mice inoculated with bacteria-induced respiratory disease. Group 1 (mushroom extract 60 ml with 60 ml tap water), group 2 (mushroom extracts 120 ml with 200 mg powder), and control (tap water 120 ml) feeds were used. Of body weight in group 2 did not show much difference. However, the total WBC count (P =0.072) and the number of neutrophils (P =0.057) tended to increase. Total number of bacteria and inflammatory cells in bronchial led to reduce the average value but was not statistically significant. Furthermore, the total number of cells in bronchial lymph node increased with increase in CD4 and CD8 ratio. The IFN-gamma and TNF-alpha for expression levels of inflammatory cytokines in bronchial lymph nodes decreased in group 2 significantly.

Recovery of microalgal biomass and dewatering are major obstructions to commercial production of microalgae for biofuel such as biodiesel. The diluted broth of harvested microalgal cultures causes a huge operational cost during recovery and dewatering process. Recovery of biomass and dewatering process requires several solid-liquid separation steps. Since the broth of microalgae culture was generally dilute, it needs to remove large volume of water from the broth. Hence, the downstream recovery process of microalgal biomass can be more expensive than the large scale cultivation process. In most cases, many harvest methods were used and claimed to contribute 20-30% to the total cost of biomass production. In this study, we used membrane filtration method for removal of water from cultivated broth of microalgae. Osmotic pressure is a natural equilibrium process and is the main driving force of this method to make the stream of water throughout the membrane. Water passes from broth of microalgae culture to outside by diffusion effect until the salt concentration on both sides of the membrane are equal.

The byssus of Mytilus species are covered by the protective coating.The hardness and stiffness of the protective byssal coating is comparable to Epoxy coating but terrifically extensible up to ~75% of their original length. The extensible byssal coating in Mytilus species have attract public attention and investigated as a source for new-coating materials due to their fascinating mechanical properties. Mytilus byssal coating contains moderate level of metal ions and a single protein –mussel foot protein-1 (mfp-1). It was reported that a robust and reversible interaction between Iron (III) and mfp-1 in water is a key factor for properties of the byssal coating. Here, we genetically produced, purified and characterized recombinant mussel foot protein-1 (Rmfp-1) for mimicking the byssal coating to design extensible coating materials. Rmfp-1 was successfully produced from E. coli as an inclusion body, purification method for Rmfp-1 from the inclusion body was established, and a property of Rmfp-1 was tested via the Surface Force Apparatus (SFA).

Thiazolidinedione (TD) derivatives exhibit algicidal activity against harmful algae such as H. akashiwo, C. marina and C. polykrikoides, as reported previously. In this study, the efficacies and selectivities of newly synthesized TD derivatives were tested by analyzing the structure–ctivity relationships of various TD derivatives. To investigate structure-activity relationships for growth inhibition of harmful algae, we added a methylene group between the cyclohexyl ring and oxygen of 5-(3-chloro-4-hydroxybenzylidene)-TD, which decreased the inhibitory potency of compound 17. Interestingly, another addition of a methylene group significantly increased the inhibitory potency against C. polykrikoides, as seen for compound 20. The addition of 1 μM compound 17 resulted in the rupture of harmful algae after less than 10 hours. Compound 17 was applied to both harmful and non-harmful algae and showed a drastic reduction in the efficiency of photosystem II, resulting in reduced photosynthetic oxygen evolution. Compound 17 at a 5 μM concentration destroyed all of the harmful algae, while algicidal activity against non-harmful algae did not exceed 30% of the control within the concentration range tested. In contrast, an herbicide, 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), tested at a 5 μM concentration, exhibited 40-70% algicidal activity relative to that of the control against both harmful and non-harmful algae. Compound 17 is a promising lead compound for the development of algicides addressing the universal need for effective harmful algal management.

Microalgae can be used to produce a wide range of metabolites, such as proteins, lipids, carbohydrates, or carotenoids. Under certain conditions, some microalgae have the potential to accumulate significant amounts of lipids (more than 50% of their ash-free cell dry weight). These characteristics give great potential for an immediate pathway to health food, feed additives, cosmetics and energy production. In this study, we compared characteristics of several marine microalgaes. Growth behavior, amounts of lipids and fatty acid composition of each microalgae strain was examined. Two strains which showed high cell concentration and produced omega-3 fatty acids were selected for further studies. Optimization of growth conditions such as compositions of medium and temperature is planned to increase biomass productivity and lipids accumulation.

Aquaculture affect the coastal environment in a variety of ways. Generally, aquaculture impact has been determined in terms of water column and sediment alterations, as well as changes in the physicochemical characteristics and structural properties of the biological components, and comparing the impacted area with a control site (2). It has been previously demonstrated that organic inputs associated to fish feeding has a substantial impact on the nutrient load in coastal areas (3). In marine sediments benthic bacterial biomass is channelled through protozoan and meiofaunal grazing to higher trophic levels. Bacteriological monitoring is of importance especially in aquaculture, in fact areas suitable for productive purposes must possess optimal quality levels (1). Coastal sediments of aquaculture wastewater enffluence area were collected at local areas of Seoungsan, Wimi, Pyoseon, and Daejeoung on Jeju-Island, Korea from July to December 2006. Bacterial communities in sediment samples were analyzed by viable cell count and spcies analyses. It was shown that 12 strains were distributed in the sediment samples at seoungsan, and 19, 12, 12 strains at Pyoseon, Wimi, Daejoung area.

Chitooligosaccharides (COS), depolymerized products of chitosan, has received considerable attention as bioactive material due to their biocompatible, biodegradable, non-toxic and non-allergenic natures. In this study, COS of four different molecular weight ranges (<1 kDa, 1-3 kDa, 3-5 kDa and 5-10 kDa) were investigated for their abilities to modulates inflammatory mediators in lipopolysaccharides (LPS)-stimulated BV2 microglia. At the concentration of 500 μg/ml, COS attenuate the productions of nitric oxide (NO) and prostaglandin E2 (PGE2) by inhibiting inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions. Furthermore, the release and expression levels of inflammatory cytokines; including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) were also attenuated by COS. Notably, the inhibitory activity of COS depends significantly on its molecular weight, with lower molecular weight showed higher activity. In addition, the suppressive effects on the phosphorylation of JNK and p38 mitogen-activated protein kinase (MAPK) by COS were confirmed. These results indicate that COS could be used as an inhibitor in regulating microglial inflammatory responses. Moreover, COS may assist therapeutic treatment of neurodegenerative diseases which accompanied with microglial activation.

In aquaculture, traditionally antimicrobial agents were incorporated in feed to stimulate growth and afford protection from diseases; however due to their extensive use the evolution of antimicrobial-resistance among pathogens (1) and the associated environmental problems have been well documented (2). Bacillus subtilis IS-2 strain was isolated from Korean food Jeot-kal. The effect of B. subtilis IS-2 (108 cell/g-1) supplemented diet fed Paralichyhus olivaceus against Streptococcus iniae with reference to the innate immune response and disease resistance was evaluated at 1, 2, and 4 weeks. Maximum reduction in mortalities was observed in kelper feeding the probiotic diet for two weeks after challenged with the pathogens when compared to the infected group fed with basal diet; similarly the cellular and humoral immune responses such as respiratory burst, serum lysozyme activity, and total protein levels increased significantly. The results reveal that, in S. iniae infected flounder feeding B. subtilis IS-2 enriched diet affords a higher level of disease protection due to stimulation of immune system.

Olive flounder Paralichthys olivaceus is one ofcommercially-important fish species, with more than 43,000 mt cultured in Jeju Island, South Korea (1). In the recent years, a number of diseases caused by bacterial, viral, and parasitic pathogens have been increased, and fish farmers have experienced substantial economic losses. Scuticociliatosis caused by histophagous opportunistic scuticociliates species belonging to the genera Uronema, Miamiensis, and Philasterides that recognized as one of the most important worldwide parasitological problems. Among Uronema marinum have resulted in severe losses in the culturing of the olive flounder farms in South Korea (1). Chemotherapy or vaccineshave been success in preventing different diseases under laboratory conditions but did not prove to be commercially viable because of their prohibitive cost of production, insufficient protection or lack of safety (2). Therefore, we report the effect of five probiotics as mixed separately in diets to investigate growth performances, feed efficiency, blood biochemistry, survival rate, and non-specific immune responses in Uronema marinum infected olive flounder on week 0, 1, 2, 4, 6, and 8. All probiotics diets significantly enhanced weight gain, feed efficiency, and high survival rate between week 6 and 8. The serum aspartate aminotransferase (GOT), alanine aminotransferase (GPT) activities, total protein (TP), glucose (GLU), superoxide anion production and serum lysozyme activity significantly enhanced in infected fish feeding with L. plantarum, L. acidophilus, and S. cerevisiae diets from week 4 to 8. The present study concluded that L. plantarum, L. acidophilus, and S. cerevisiae supplementation diets act as immunostimulants that enhance the growth, feed efficiency, blood biochemistry, survival rate, and non-specific immune responses in U. marinum infected olive flounder..

Botryococcus braunii produce large quantities of lipids using CO2 and solar energy, which have a potential of renewable energy source. In this work, we studied the characteristics of hydrocarbons which are produced from B. braunii LB 572. The portion of hydrocarbons was selectively extracted from B.braunii LB 572 with n-hexane. Melting point, calorific value, and elemental composition were measured to be 27~33℃, 10,191kcal/kg, and (CH2.105O0.041)n respectively. The calorific value of hydrocarbons from B. braunii LB572 is higher than that of general biodiesel, a representative renewable fuel, and also extraction process is relatively simple. The hydrocarbons from B. braunii LB 572 are considered as a potential source of renewable fuel.

This study explains the novel possibility of the involvement of gallic acid conjugated chitooligosaccharides (G-COS) in ameliorating cellular antioxidant activity. The free radicals scavenging activity of G-COS was assessed by using an electron spin resonance technique. In addition, the inhibition of reactive oxygen species, lipid, protein, and DNA oxidation were determined in mouse macrophages (RAW264.7 cells) and human chondrosarcoma (SW1353 cells). Moreover, the antioxidative mechanism of G-COS was evaluated by protein and gene expression levels of antioxidant enzymes (superoxide dismutase and glutathione). Western blot analysis revealed that G-COS inhibits radical-mediated expression and activation of NF-kB proteins (transcription factor in the regulation of expression of numerous genes in the setting of the osteoarthritic response). Based on the results of this study, G-COS can be used as a scavenger in controlling free radicals that lead to damage to cellular systems in osteoarthritis.

While international trade of penaeid shrimp has contributed to development of penaeid shrimp culture, it has resulted in introduction of infectious diseases into new geographical regions by transfer of infected postlarvae of broodstock to outside the original locations (1, 2, 3). A filamentous form of mollicute-like bacterium was detected during a routine health survey of wild adult kuruma shrimp Penaeus japonicus. The kuruma shrimp were native to Japan and were imported to Korea. The histology showed no pathological changes. Transmission electron microscopy revealed extensive infections of hepatopancreatic epithelial cells by a pleomorphic, filamentous intracellular bacterium. The filamentous bacterium was of about 600㎚in diameter and 300㎚to more than 1 ㎛in length. The morphology of bacteria were filamentous and branched with terminal blebs, or knobs, on the branches. They lacked the cell wall, and were bounded by the plasma membrane. They contained typical prokaryotic ribosomes and fibrillar DNA-like strands. No additional internal structure has been observed. They are considered to be mollicutes, based upon the morphological appearance and upon the cellular location.

Microalgae are being considered as one of potential renewable energy sources. Microalgae-derived lipid can replace fossil fuels because of its lipid productivity is more than 30 times that of soybean, and also scavenging CO2, a representative environment pollutant. Botryococcus braunii produce a lot of lipids, it is being studied for new energy producer but only the hydrocarbon among its lipids has been focused. We have researched production of biodiesel, alkyl ester of fatty acid, with Botryococcus braunii LB 572. The lipids convertible to biodiesel were selectively extracted after separation of hydrocarbons from dry cell. Fatty acid methyl ester was successfully transformed from the lipid. The content of unsaturated fatty acids was more than 90%. The unsaturated fatty acids has relatively high oleic acid(16:1 fatty acid) content. Cloud point of the fatty acid methyl ester was 4℃. As a result, B. braunii can be used to produce not only bio-hydrocarbons but also biodiesel and is a good renewable energy source.

A marine bacterium possessing a novel activity of alginate degradation was isolated from a brown seaweed soup liquefied by salted and fermented anchovy. The isolated strain was designated as Brevundimonas sp. MJ-3 based on the analysis of biochemical characteristics and cellular fatty acid composition. The alginate lyase gene was cloned from genomic DNA library and expressed in Escherichia coli. The optimal pH and temperature for the recombinant alginate lyase were 7.0 and 40oC, respectively. When the multiple sequence and conserved domain were analyzed, interestingly, the cloned gene product was predicted to consist of alginate lyase L-like protein domain and Heparinase-like protein domain. The final degradation product of alginate was analyzed by ESI-MS and proved to be unsaturated monosaccharides. Based on the results, the cloned gene possessed an exotype alginate lyase activity that can degrade the alginate into monosaccharides. Acknowledgement : This work was supported by New &Renewable Energy R&D program (20093020090020) under the Korea Ministry of Knowledge Economy (MKE) and Korea Industrial Technology Foundation (KOTEF) through the Human Resource Training Project for Strategic Technology.

Recently, microalgae emerge as strong candidates for the sustainable production of biofuels. In this study, we demonstrated the influence of temperature and light intensity on the growth rate and fatty acid composition of marine microalgae, Isochrysis sp. and Chrollera salina. Cell culture was performed in a 100 mL flask using two kinds of medium (seawater medium and f/2 medium). The change of cell growth rate and fatty acid composition was investigated according to three different temperatures (15, 20, 25 ℃) and four different light intensities (1500, 3000, 4500, 6000 lux). Fatty acid composition was analyzed using gas chromatograph (GC). We expect that this work would contribute to mass production of microalgae by providing information about culture conditions.

As the price of conventional fossil fuels rise, renewable liquid fuels have become more attractive. Lipids from marine microalgae draw a lot of interests as a feedstock for biodiesel. Among various factors affecting marine microalgal culture other than light-related parameters, CO2 concentration, salinity and temperature found to be the important factors affecting the biomass and lipid production of Dunaliella tertiolecta. In order to examine the influence of these factors on cell growth and lipid production, D. tertiolecta has been cultivated under a certain range of CO2 concentrations (Air and 2, 5, 10% CO2 enriched air), salinities (2 ~ 4% with 0.5% interval) and temperature (5, 10, 15, 20, and 25℃) in 0.4 L bubble column photobioreactors (PBRs). The results indicated that the growth rate and biomass were the highest at 2% CO2. When the cells grew without CO2 enrichment, pH was increased from 6.5 to 10 and the elevated pH induced the cells to attach on the PBR wall. D. tertiolecta grew well in the range of 15~25℃ showing the optimal growth at 21℃ but the strain cannot survive below 10℃. The highest final dry cell weight (DCW) was observed at 2% salinity. Lipid contents per DCW, however, became higher as the salinity increase till 4%, while the final cell concentration decreased as the salinity increased. Salt stress (salt shock) was also examined at mid-log phase resulting the lipid content from 51.4% to 57.3% without biomass loss. As a result, salt shock may be a better practice than maintaining high salinity during the entire culture.

The chemistry of mussel adhesion has commanded the focus of much recent research activity on wet adhesion. By comparison, the equally critical adhesive processing by marine organisms has been little examined. Using a mussel-inspired coacervate formed by mixing a recombinant mussel adhesive protein (fp-151-RGD) with hyaluronic acid (HA), we have examined the nanostructure, viscosity, friction, and interfacial energy of fluid-fluid phase-separated coacervates using the surface forces apparatus and microscopic techniques. At mixing ratios of fp-151-RGD:HA resulting in marginal coacervation, the coacervates showed shear-thickening viscosity and no structure by cryo-transmission electron microscopy (cryo-TEM). However, at the mixing ratio producing maximum coacervation, the coacervate showed shear-thinning viscosity and a transition to a bicontinuous phase by cryo-TEM. The shear-thinning viscosity, high friction coefficient (>1.2), and low interfacial energy (<1mJ/m2) observed at the optimal mixing ratio for coacervation are promising delivery, spreading and adhesion properties for future wet adhesive and coating technologies.

Antrophogenic carbon dioxide (CO2) accumulation causes serious problem on surface temperature of Earth, subsequently the investigations have been carried for the mitigation of CO2. Photoautotrophic organisms utilize CO2 as carbon source and play vital role in carbon cycle. Carbonic anhydrase(CA, EC 4.2.1) accelerates to uptake of CO2 from air into intracellular system in addition to the diffusion process during carbon fixation. In this study, three types of CA in two strains of marine microalga Dunaliella sp., and Phaeodactylum tricornutum CCMP 632 were identified. In Dunaliella sp., two types of CA, namely alpha- and gamma-type CA were isolated and cloned. The alpha-type CA of 589 amino acids was 99% homologous to duplicated CA in Dunaliella salina [1]. The gamma-type CA in Dunaliella sp. was 60% similar to that of Chlamydomonas reinharditii. And we are under investigating putative three types of CA in marine diatom P. tricornutum CCMP 632. Among these CAs, the transcriptional and translational expression patterns of alpha-type CA in Dunaliella sp. at various concentrations of CO2 have been studied.

The complexity of biological system is fascinating and challenging for human for a long time. With the advents of mathematical tools with various omics technology, systems biology was born and it’ already ubiquitous in every area of biology and biotechnology. Microalgal biotechnology is no exception in this new trend. As tens of microalgal genomes publicly available on the internet, vast amount of data from genomics, transcriptomics, and proteomics are reported everyday. Though there are not enough data on microalgal metabolomics yet, the in silico models for relatively simple cyanobacteria or for organelles, such as chloroplasts, will appear sooner or later. With the help of systems biology, deeper understanding of microalgae will be possible. Consequently, most of industrially-interested microalgae can be metabolically redesigned as cell factories and microalgae will be served as the hosts as commercially attractive strains.

Microalgae have been seen all over the seawater and fresh water. Specially, Spirulina maxima and Chlorella vulgaris are extensively use in human nutrition because it is a source of beneficial protein, unsaturated lipids and vitamins. In the study, light-emitting diodes (LEDs) with different light wavelengths (red, green, blue, white) and various levels of light intensity (750, 1500 and 3000 μmol m-2 s-1) were applied to explore the effect of light source on photoautotrophic cultivation of Spirulina maxima and Chlorella vulgaris. In the case of Spirulina maxima, red LED exhibited the highest specific growth rate of 0.035 h-1 in the exponential growth phase and the cell number of 3.1 x 106 ml-1 at the plateau under the illumination of 3000 μmol m-2 s-1, Whereas blue LED showed the least efficiency. Also, Chlorella vulgaris showed the highest specific growth rate of 0.019 h-1 and the cell number of 2.0 x 106 ml-1 under illumination of white LED (3000 μmol m-2 s-1). In comparing the economic efficiency of energy to biomass, the use of red LED and white LED gave the most effective performance for the photoautotrophic cultivation of Spirulina maxima and Chlorella vulgaris, respectively.

Alginate is a gelling polysaccharide found as a major constituent of the cell wall and intracellular material in the brown seaweeds, Macrocystis, Laminaria and Ascophyllum. For the purposes of specific physical and biochemical properties, short length alginate, oligoalginate can be obtained by acid hydrolysis or alginate lyases. Alginate is a complex copolymer of α-L-guluronate (G) and its C5 epimer b-D-mannuronate (M), arranged as homopolymeric G blocks, M blocks, random heteropolymeric G/M blocks. Alginate lyases, also known as alginases or alginate depolymerases, catalyze the degradation of alginate by a b-elimination mechanism. Some bacterial strains produce several alginate lyases with different substrate specificities (polymannuronate lyase, EC 4.2.2.3, polyguluronate lyase, 4.2.2.11 and oligoalginate lyase, 4.2.2.-). In this study, the alginate lyase from Streptomyces sp. M3 which showed polyG-specific lyase activity was mutated for enhancing the lyase activity by using Stratagene random mutagenesis kit. When phenylalanine at residue 98 was replaced by leucine, the depolymerizing activity was decreased completely. Mutation of residue 197 with cysteine increased the activity about four fold compared to original M3 lyase. Acknowledgement : This work was supported by New &Renewable Energy R&D program(20093020090020) under the Korea Ministry of Knowledge Economy(MKE) and Korea Industrial Technology Foundation (KOTEF) through the Human Resource Training Project for Strategic Technology.

Due to the limited fossil fuels and the continuing global warming, we need renewable clean energy. Microalgae can be more suitable alternative source for biodiesel because of its high lipid contents, rapid growth rate and high photosynthetic efficiency. The objective of this study is to optimize lipid production and productivity in Chlorella vulgaris C-27 under various culture conditions using statistical method such as Fractional Factorial Design (FFD) and Central Composite Design (CCD). They are powerful tools to optimize culture conditions and to improve productivity of target materials from cultures. First of all, we carried out FFD, in order to investigate environmentally effective factors among light intensity, CO2 concentration and flow rate, followed by the 2nd FFD to identify the effect of each component of the medium on lipid production in C. vulgaris C-27. As the results, CO2 concentration and magnesium are significant factors for efficient lipid production in C. vulgaris C-27.

Although Korean climate condition cannot provide steady light condition for outdoor culture of algal, utilization of sun light energy still has numerous benefits. Therefore, it is necessary to investigate how to maximize the efficiency of solar energy utilization by supplementing minimal amount of artificial light. Night Biomass Loss (NBL) was measured under natural conditions without supplying artificial light during night time. The results have shown that NBL quantity under natural condition was 30% higher than under continuous light condition which was illuminated by sun light during the day and by artificial light at night. In order to reduce NBL, artificial light was provided during night time and effect of intermittent light was investigated by changing the intermittent light time with 30, 60, and 150 minutes with light and dark ratio as 1:1. The average of the fresh cell weight obtained under intermittent light was 2.67 g/L, whose NBL was reduced by 62% compared to the NBL under natural condition. In terms of relative electric power and photon yield, the intermittent time with 150 minutes was 72% higher than it was with continuous light condition. As the intermittent light time extended, certain fatty acid methyl ester concentration of C18:1 and C18:3 was increased.