• ALGAE
• /
• v.21 no.1
• /
• pp.141-148
• /
• 2006

Benthic diatoms are known as a good food for shellfish in nature and in commercial hatchery of Jeju Island, Korea. Grammatophora marina is commonly found as dominant benthic micro-algae in Jeju coastal waters throughout the year. To know the best growth conditions of this species, culture was done in terms of three parameters; water temperature, salinity and nutrients. Each parameter was controlled by temperature of 15, 20 and 25°C; salinity of 25, 30 and 35 psu; and nutrient concentrations of 50, 100 and 200%. F/2 media was used with artificial seawater for the culture, which was continued for two weeks with L:D cycle 12:12 by using fluorescent light. Maximum specific growth rate was recorded 1.68 d–1 at temperature of 25°C with salinity of 35 psu and nutrient concentration of 200% on 6th day during the culture period. Maximum biomass was also observed 4.9 × 105 cells mL–1 in the same condition. This species may belong to the euryhaline and eutrophic habitat with warm condition. For nutritional aspects of this species, protein, lipid and carbohydrate were measured. The value of protein, lipid and carbohydrate was 4.96%, 15.82% and 5.65%, respectively. The antioxidant activities of 80% methanolic extract were 46.7%, 23.7% and 23.8% on DPPH (1,1-Diphenyl-2-picrylydrazy) radical, superoxide anion radical and hydrogen peroxide scavenging, respectively. Percentage metal chelating activity was 81.2%. Enzymatic extracts of Alcalase and Ultraflow showed remarkable scavenging activities on DPPH radical (86.5% and 57.2%, respectively), and superoxide anion scavenging activities were 45.3% and 41.4% from Kojizyme and Viscozyme extracts, respectively. Extract of Protomex revealed 24.8% activity on hydrogen peroxide and Neutase showed 30.8% on hydroxyl radical scavenging effects. Celluclast and Viscozyme extracts showed 33.2% and 32.1% activities on nitric oxide scavenging, respectively, while Alcalase showed 61.5% on metal chelating. This species contains higher lipids among the biochemical compounds and higher metal chelating activities from both 80% methanolic and enzymatic extracts.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.35 no.5
• /
• pp.476-479
• /
• 2002

We observed the succession and appearence species of the marine benthic diatoms for the effective seed production of shellfish culture on wave plates in indoor mass culture tanks. Every five days, the existence species and densitiy of diatoms were counted during the 20 culture days. Experimental conditions were 8.5 $\pm$ 0.3$^{\circ}C$ of water temperature, 1.0250$\~$1.0260 of specific gravity, 2,200$\~$13,000 lux of light intensity. The total density of appearence species was rapidly increased with the lapse of time. However, the number of appearence species decreased on the 20th day. The diatoms observed were 10 species; Navicula sp. of, viridula, Cylindrotheca closterium, Licmophora sp., Pleurosisma normnii, Bacillaria Paradoxa Asterionella glacialis, Stephanopuis sp. cf, turris, Entomoneis sp., Odontella aurita and Cocconeis sp, cf, scutellum. Of them, Navicula sp, of, viridula was most dominant throughout the experiment.

• Journal of the Korean Society of Food Culture
• /
• v.23 no.3
• /
• pp.318-327
• /
• 2008

This study examined the cultural dietary habits as well as attitudes toward food, within other life pattern elements, of students living in Gwangju City and Chonnam Province, Korea. Questionnaires from 1,000 student respondents were analyzed. The survey consisted of questions regarding physical condition and health status, dietary consciousness, food preference, knowledge of food and nutrition, and dietary culture. The results showed that 1.6% of the students considered their own physical condition to be extremely poor, and 2.7% and 2.1% also considered their father's and mother's physical conditions as extremely poor, respectively. Among the respondents, 18.3% were smokers and consumed an average of 14.8 cigarettes per day. With regard to their dietary habits, the students answered that they preferred to eat meals with friends rather than with family members, fruit was chosen for eating over health food supplements, and there was very little participation or interest in various food and cultural festivals. The female students had a tendency to alleviate mental stresses by eating, while the male students performed more physical activity to deal with stress. The female students also preferred cereal, fruit, fast food, and sweetened foods more than the male students. Between the smokers and non-smokers, significantly more non-smokers chose fruit (p<0.01), ethnic foods (p<0.05), and sweetened foods (p<0.05) as compared to the smokers. Body mass index (BMI) had significant positive correlations with soft drink (p<0.01), health food supplement (p<0.01), and alcoholic beverage (p<0.001) consumption, while BMI was negatively correlated with cereal (p<0.01), fruit (p<0.001), and sweetened food (p<0.01) intake. The health status of students was positively correlated with their father's health status (p<0.01), mother's health status (p<0.001), and BMI (p<0.05), as well as cereal (p<0.001), high protein side dish (p<0.01), fruit (p<0.01), vegetable (p<0.01), and traditional food (p<0.001) intake. The average body weight for female students was approximately 5 kg less than the Korean Nutrition Society's standardized weight, therefore, it is strongly recommended that measures be taken to develop a systematic nutrition education program that would help those students who often unintentionally skip breakfast or go on extreme diets to improve body image.

• Journal of Marine Bioscience and Biotechnology
• /
• v.15 no.2
• /
• pp.82-89
• /
• 2023

Microalgae, as photosynthetic organisms, possess the ability to produce a diverse array of bioactive compounds. This study focused on the transformant Chlamydomonas reinhardtii dZL and subjected it to cultivation under varying light intensities (60, 120, 180, and 240 µmol/m²/s). Our aim was to assess the impact of light intensity on both microalgal biomass and carotenoid production. The cultivation took place in 80 mL bubble column photobioreactors, specifically the Multi-cultivator. Notably, the culture exposed to 240 µmol/m²/s exhibited the most rapid cell growth, surpassing even the cell concentration achieved at 180 µmol/m²/s by day 8. A detailed analysis of the specific irradiance rate over time unequivocally revealed a sharp decline in growth rates when the rate fell below 2 × 10^-10 µmol/cell/s. Although the culture with 60 µmol/m²/s yielded the highest carotenoid content (1.2% of dry weight), the culture exposed to 240 µmol/m²/s recorded the highest carotenoid concentration at 8.9 mg/L owing to its higher biomass. Our findings reveal the critical importance of maintaining a specific irradiance rate above 2 × 10^-10 µmol/cell/s to enhance biomass and carotenoid productivity. This study lays the groundwork for defining optimal light intensity conditions applicable to mass culture systems, with the objective of augmenting C. reinhardtii biomass and optimizing carotenoid productivity.

• Journal of Plant Biotechnology
• /
• v.29 no.1
• /
• pp.37-40
• /
• 2002

Sweet potato is a crop vegetatively propagated by vine cuttings, an ineffective method for maintaining pathogene-free stock plants. As an alternative method, single-node cultures of virus-free plantlets derived from apical meristem in sweet potato (cv. Yulmi) was examined. Effective pH range, sugar concentration and nodal order were investigated to establish an in vitro mass propagation system with high quality virus-free stock plantlets to farmhouse. Although the plantlets grew at wide range of pH, the most effective pH of the medium was 4.8 in single-node cultures. High sugar concentration of 60∼80 g/L resulted in increased growth response in shoot length, root length, number of node, leaf area and fresh and dry weight of shoot and root, whereas reducing sugar contents below 6% was showed reduced growth response. The first node including meristem tip was the best for the rapid growth of plantlets and the other nodes also showed a very similar growth response. Uniform plantlet can be obtained massively at the same time by culture of single node except for the first node including meristem tip. In conclusion, the most effective pH range and sugar concentration of medium for the growth of plantlets via single-node cultures was 4.8, 60∼80 g/L respectively. The first node was the best for the rapid propagation of plantlets in nodal order.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.2
• /
• pp.745-754
• /
• 2021

The purpose of this study was to evaluate and verify the effectiveness of sustainable cosmetic raw materials developed from Gynostemma pentaphyllum, a plant native to Ulleungdo, in improving the skin barrier function and treating atopic dermatitis. Cells were derived from adult Gynostemma pentaphyllum plants, and suitable conditions for mass culture of the cells were established in a bioreactor. DNA components and amino acids extracted from this mass culture were identified from the HPLC fraction. In the in vitro efficacy evaluation results, changes in the expression levels of skin barrier-related proteins such as filaggrin (FLG) and Zonula occludens-1 (Zo-1) were insignificant. It was confirmed that the expression levels of the proteins thymic stromal lymphopoietin (TSLP) and interleukin-33 (IL-33) were significantly reduced. These results lead to the conclusion that Gynostemma pentaphyllum cell extracts have significant anti-inflammatory effects and that these extracts can be widely used as sustainable, nature-friendly active material in cosmetics with anti-inflammatory effects and targeted at improving atopic dermatitis.They may find use in anti-aging cosmetic products as well.

• Journal of Life Science
• /
• v.28 no.8
• /
• pp.938-944
• /
• 2018

This study evaluated tyrosinase, elastase inhibitory, and antioxidant activities of fermented Rhododendron micranthum Turcz. extract using a lactic acid bacterium, Lactobacillus rhamnosus. The optimum conditions for fermentation of R. micranthum Turcz. extract were $37^{\circ}C$ and 3% R. micranthum Turcz. extract for 3 days based on the bacterial cell number, total phenolic compounds, DPPH radical scavenging activity, and tyrosinase and elastase inhibitory activity. After culture for 3 days using 3% R. micranthum Turcz. extract, the cell mass of L. rhamnosus reached $5.7{\times}10^9CFU/ml$. The results indicated that R. micranthum Turcz. extract can be used for industrial lactic acid bacteria culture. After fermentation under optimum conditions, the total content of phenolic compounds of the fermented R. micranthum Turcz. extract was 157 GAE mg/ml, and the $IC_{50s}$ of DPPH radical scavenging activity, ABTS radical scavenging activity, and tyrosinase and elastase inhibitory effects were 78.8, 79.8, 329.1, and $449.5{\mu}g/ml$, respectively. The fermented R. micranthum Turcz. extract exhibited 1.2-, 1.3-, 1.5-, 2.4-, and 5.6-fold higher total content of phenolic compounds, DPPH radical scavenging activity, ABTS radical scavenging activity, and tyrosinase and elastase inhibitory effects than the nonfermented R. micranthum Turcz. extract. These results indicated that fermented R. micranthum Turcz. extract using L. rhamnosus can be used for developing new natural functional ingredients for the health food or cosmetic industry.

• Journal of Plant Biotechnology
• /
• v.35 no.2
• /
• pp.109-114
• /
• 2008

The aim of this research is to establish the conditions for Agrobacterium-mediated genetic transformation using microspore. The embryo induction from the microspore was examined under several Kanamycin concentration in media, and the induction rate decreased about 4, 8, 10 times when the Kanamycin concentration increased 10, 50, 100 mg/L, respectively. This indicates that the transformation rate would be much lower if the Kanamycin was used for selection marker. In order to apply the GFP gene as a reporter gene for Agrobacterium-mediated genetic transformation, GFP expression from the microspore-mediated embryos was observed using GFP filter under microscope. The GFP expression occurred when the microspore cultured toward the embryo development for 12, 24 and 48 days. The microspore formed a cluster by microspore division from 12 days culture and continuously became a bigger mass. We obtained a total of 8 GFP-expressing embryos suggesting that the transformation of microspore occurred. However, those young embryos were not fully developed. Further study pertinent to culture conditions is required to fulfill the Agrobacterium-mediated genetic transformation using microspore.

• Microbiology and Biotechnology Letters
• /
• v.45 no.2
• /
• pp.124-132
• /
• 2017

Microbial secondary metabolites of marine organisms are regarded as major sources of structurally and biologically novel compounds with numerous potential uses. Sponge-microbe associations are among the most interesting sources for exploring bioactive compounds. In this study, the bacterial strain Microbulbifer sp. (127CP7-12) was isolated from the Asian marine sponge Hymeniacidon sinapium collected at an intertidal zone on the west coast of Korea. Cultured bacteria produced a violet pigment, and optimal culture conditions for violet pigment production were investigated. Maximum production of the violet pigment from the strain culture was observed under the conditions of $25^{\circ}C$, pH 6.0, and 3% NaCl. Acetone provided better extraction of the pigment from fermented broth compared with ethanol and methanol. The proposed structure of the major component in the extracted crude pigment was determined via high-performance liquid chromatography, nuclear magnetic resonance, mass spectrometry, and UV spectra analyses, which showed that the metabolite was the promising bioactive compound violacein. This study describes the examination of marine bioactive materials from microbe-engaged metabolites and the ecological implications of the sponge-microbe association in a changing ocean.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.11
• /
• pp.1612-1617
• /
• 2009

Aspergillus sp. 101 was isolated from the Korean traditional soybean paste for the production of a salt-tolerant protease. The optimal condition for the production of a salt-tolerant protease was determined with various energy sources such as carbon, nitrogen, and protein, and at different culture conditions such as temperature, pH, incubation time and NaCl concentration. The most favorable organic nitrogen sources were 2% defatted soybean flour (DSF) and soy protein isolate (SPI). Optimal pH and temperature were pH 6.0 and $25{\sim}27^{\circ}C$, respectively. Therefore, Aspergillus sp. 101 protease was a mild acid (or neutral) protease. Protease production was the highest at 0.1% concentration of $CaCO_3,\;K_2HPO_4$ and Arabicgum. Aspergillus sp. 101 could grow in culture medium at 15% NaCl concentration and produce a salt-tolerant protease even at 7% NaCl. The cell mass and protease activity of Aspergillus sp. 101 cultured in a modified medium was comparatively higher in Czapek dox and protease producing media. Hence, Aspergillus sp. 101 protease can be utilized in soy or fish sauce industry as a salt-tolerant protease starter.