• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.2
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• pp.144-153
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• 2014

Both docosahexaenoic acid (DHA, 22:6n-3) and eicosapentaenoic acid (EPA, 20:5n-3) have attracted increasing attention since the first epidemiological report on the importance of n-3 essential fatty acids. Lipids in microbial cells play various biological roles and, consequently, much research has been carried out on their role in cell physiology. The lipid composition of microorganisms can exhibit considerable variations depending on environment. The effects of culture conditions, temperature (15, 20, 24, 28, 32 and $36^{\circ}C$), salinity (10, 20, 30, 40 and 50 psu), pH (pH5, 6, 7, 8 and 9), rotation speeds (50, 100, 150 and 200 rpm), carbon sources, nitrogen sources and C/N ratio on the production of docosahexaenoic acid, fatty-acid profiles, and acids secreted to the broth culture by the oleaginous microorganism, Schizochytrium mangrovei (KCTC 11117BP), were studied. Temperature (initially $28^{\circ}C$), salinity (20 psu), pH (pH7), rotation speeds (100 rpm), organism fatty acids, and secreted acids in the broth were varied during cultivation of S. mangrovei. At pH 7.0, S. mangrovei was able to accumulate lipids up to 40% of its biomass, with 13% (w/w) DHA content. The monosaccharides glucose and fructose, and yeast extract were suitable carbon and nitrogen sources, respectively. The primary omega-3 polyunsaturated fatty acid produced was docosahexaenoic acid.

• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.29-34
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• 2005

W/O/W (water-in-oil-in-water) type multiple emulsion was applied to improve the storage stability of an antagonistic microorganism, Burkholderia gladioli. Encapsulation of microorganism into a W/O/W emulsion was conducted by using a two-step emulsification method. W/O/W emulsion was prepared by the incorporation of B. gladioli into rapeseed oil and the addition of polyglycerin polyriconolate (PGPR) and castor oil polyoxyethylene (COG 25) as the primary and secondary emulsifier, respectively. Microcrystalline cellulose was used as an emulsion stabilizer. To evaluate the usefulness of W/O/W emulsion formulation as a microbial pesticide for controlling the bacterial wilt pathogen (Ralstonia solanacearum), the storage stability and antagonistic activity of emulsion formulation were tested in vitro. The storage stability test revealed that the viability of formulated cells in emulsion was higher than that of unformulated cells in culture broth. At $4^{\circ}C$, the viabilities of formulated cells and unformulated cells at the end of 20 weeks decreased to about 2 and 5 log cycles, respectively. At $37^{\circ}C$, the viability of formulated cells decreased to only 2 log cycles at the end of storage. On the other hand, the viable cells in culture broth were not detected after 13 weeks. In activity test, formulated cells in emulsion were more effective in inhibiting the growth of pathogen than unformulated cells in culture broth. Unformulated cells completely lost their antagonistic activity during storage under similar conditions. The W/O/W multiple emulsion formulation was shown to be useful as the novel liquid formulation for biological control.

• KSBB Journal
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• v.25 no.1
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• pp.79-84
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• 2010

In the present study, we isolated a new bacterial strain producing invertase (EC 3.2.1.26) and determined optimized culture condition in flask culture. The strain was identified as Bacilus flexus determined by the 16S rDNA sequencing method. The invertase was produced only in the sucrose medium as the sole carbon source. Potassium nitrate was an adequate nitrogen source for enzyme production, whereas meat peptone showed the highest bacterial growth. Enzyme production was increased about 2-fold when $MgSO_4\cdot7H_2O$ was supplemented to the growth media. The optimum temperature was found to be $30^{\circ}C$ for both enzyme production and bacterial growth. Invertase exhibited pH optima in the range 5.0-6.0 and have a temperature optimum at $40^{\circ}C$, similarly to other invertases found from different microbial sources. Several mineral ions (K and Fe) stimulated the invertase activity, whereas some bioelements (Ag, Mg, and Mn) inhibited enzyme activity. Under the optimized culture condition, the maximum enzyme production (over 250 units/mL) was achieved at 20 h. To the best of our knowledge, this is the first time to report on invertase production by Bacilus flexus.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.8
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• pp.1110-1115
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• 2005

To study the effect of feeding lactic acid producing bacteria on the performance of cattle calves, twenty four, day old male crossbred cattle calves (Bos indicus${\times}$Bos taurus), were distributed into two groups of 12 animals each. The animals were fed on calf starter containing wheat bran and green berseem ad libitum and milk as per requirement upto 8 weeks of age. The diet of calves of Group 2 was supplemented with 500 ml culture of Lactobacillus acidophilus-15. Total duration of the experiment was 31 weeks. There was no significant difference in intake and digestibility of dry matter (DM), organic matter (OM), neutral detergent fibre (NDF), acid detergent fibre (ADF) and crude protein (CP) between the groups. The rumen pH, protozoa numbers, concentration of volatile fatty acids (VFA), ammonia nitrogen ($NH_3-N$), trichloroacetic acid precipitable nitrogen (TCA-ppt N) and activity of microbial enzymes (carboxymethylcellulase, xylanase, amylase and protease) were not affected due to probiotic supplementation. Average live weight gain of the calves was improved (about 10%) and feed:gain ratio was reduced (about 5%) in the animals given Lactobacillus culture. The data indicated that crossbred calves could be reared on a diet devoid of cereal grain and addition of Lactobacillus culture in the diet resulted in an added advantage in growth performance of the animals.

• Microbiology and Biotechnology Letters
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• v.18 no.3
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• pp.273-279
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• 1990

For poly- $\beta$ -hydroxybutyrate (PHB) production, a pink-pigmented facultative methylotrophic bacterium (PPFM) P-10 was newly isolated from soils through methanol-enrichment culture. The optimal medium composition for cell growth was 1.0% (vlv) of methanol as carbon source and l.Og/l of ,TEX>$NH_4Cl$, equivalent to C/N ratio of 13.2 at pH 7.0 and $30^{\circ}C$. To investigate the optimal condition for YHB accumulation, two-stage culture technique was adopted; first stage for cell growth and second stage for accumulation of PHB providing unbalanced growth conditions. The optimal PHB accumulation was 1.0% (vIv) of methanol and 0.26gll of $NH_4Cl$, C/N of 50.8 at pH 6.0. To overcome methanol inhibition on cell growth, intermittent feeding fed-batch culture technique was employed, and the cell concentration as high as 14gll with 40% of PHB was achieved. The purified PHB was identified using IR and $1^H NMR$ as homopolymer of 8hydroxybutyric acid. The absorption spectrum of extracted pink colored microbial pigment was alsa investigated.

• Journal of Plant Biotechnology
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• v.43 no.1
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• pp.99-103
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• 2016

In perennial ginseng plantations, the effective control of various diseases is one of the most critical factors for increasing yields. Enhancing the resistance to disease through induced systemic resistance (ISR) and anti-microbial activity of beneficial soil bacteria, is currently considered to be a potential promising approach to integrate pathogen management for sustainable agriculture. However, the effective in vitro culture systems for testing ISR in ginseng plants have been rarely reported. In this study, I have successfully developed an in vitro germ-free culture system of Panax ginseng seedling for diverse purposes. With this useful system, we also tested BTH-induced priming effects against Botrytis cinerea and Colletotrichum panacicola. Compared to the drain method for enhancing ISR effects to ginseng seedlings, the direct method of spraying leaves somewhat increased the defense activity to these major fungal pathogens. Consistently, the expression of pathogen related PgPR10 and PgCAT were greatly and rapidly enhanced in the BTH-treated ginseng seedlings by treatment with C. panacicola. Our results revealed that the in vitro culture system can be used for developing eco-friendly and versatile bio-control agents for harmful diseases in ginseng cultivation.

• Korean Journal of Veterinary Service
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• v.30 no.2
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• pp.219-231
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• 2007

The effects of intraduodenal administration of Clostridium perfringens type D whole culture in goats were evaluated to develop a reliable experimental model of enterotoxemia in this species and the eventual evaluation of treatment with different drug preparations was also carried out. A total of 28 conventionally reared healthy unvaccinated black bangle goat kids of 6-12 months of age were dosed intraduodenally with whole cultures of C peliringens type D. Four kids were used as controls and received sterile, nontoxic culture medium intraduodenally. All animals received starch solution into the abomasum. The clinical signs developed within 12 hours of post inoculation that were similar to those observed in naturally occurring cases. Among the clinical signs, diarrhea was most common (96.43%) followed by dyspnea (53.57%) and central nervous system (CNS) signs (25.0%). The most striking postmortem findings consisted of necrotizing pseudomembranous colitis (100.0%), lung edema (69.23%) and fluid filled intestines (61.53%). The protocol thus provided a reasonable model of naturally occurring enterotoxemia in goats, producing a range of clinical signs and postmortem changes similar to those observed in the natural disease. Beside this, treatment trial with different drug preparations showed penicillin combined with antitoxin was most effective (100.0%), followed by combination of oxytetracyclin with antitoxin, and combined preparation of antitoxin and sulfur drugs both showed 75% recovery rate. On the other hand, treatment with antitoxin, penicillin and oxytetracycline singly could protect goat enterotoxaemia only 25.0%, 50.0% and 50.0%, respectively. Thus in the present study, it eas observed that antisera in combination of antibiotics gave better recovery rate than the antitoxin or antibiotics alone.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.3
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• pp.119-126
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• 2001

A process for the production of bioplastics from wastewater with an open microbial culture was developed and evaluated. The process consists of a selection reactor to select bacteria in feast/famine regime and an accumulation reactor to produce PHA using selected bacteria. Polyhydroxyalkanoate(PHAs) accumulating bacteria could be efficiently grown in a sequencing batch reactor(SBR) without any growth limitation. For the high production of PHA limitation such as oxygen and nutrients seemed to be needed. Accumulation experiments were performed to evaluate the level of accumulation of PHA. Limited aeration had no effect, but nutrients limitation showed high accumulation. Bacteria which were selected in the SBR could accumulate PHA till 60% of cellular dry weight in accumulation experiments under nitrogen limitation. PHA accumulation rate decreased with increasing PHA content in the cells. Clearly, PHA accumulation rate has a strong correlation with the PHA content of the cells.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.2
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• pp.272-276
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• 2011

Paeonia japonica has been widely used as a folk remedy for a long time. This study was performed to investigate antimicrobial substance of P. japonica extracted with petroleum ether, chloroform, ethylacetate, methanol or hot water. The antimicrobial activities of the P. japonica extracts were determined using a paper disc method and liquid culture. The methanol fraction at a concentration of 10 mg/mL showed the strongest antimicrobial activity against Salmonella typhimurim KCCM 11862. The ethylacetate fraction (5 mg/mL) showed the highest antimicrobial activity against Staphyloccoccus aureus KCCM 11593. In a study using liquid culture, the ethylacetate fraction from P. japonica showed the highest anti-microbial activity against S. aureus KCCM 11593 in a concentration range of 5~10 mg/mL. All fractions prepared from P. japonica inhibited the growth of S. aureus KCCM 11593 under our culture conditions.

• Journal of the Korean Society of Food Culture
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• v.30 no.1
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• pp.1-7
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• 2015

Traditional cuisine reflects cooking traditions shaped by political, economic, social, cultural, and environmental conditions characterized by authenticity and uniqueness. Traditional food is not only a part of our cultural heritage but also a knowledge resource. Application of food science and technology in Korean traditional foods was reviewed from six points of view, including food preservation, fermentation, changes in food materials, utilization of food functionality, and packaging and development of cooking appliances. Books from disparate times were chosen in order to cover a wide range of materials from the past to the present. Food preservation and fermentation techniques were applied to various food materials. Combination of science and skills contributes to the accessibility of diverse food materials and better quality foods. Koreans use assorted and resilient plants, which have an abundance of functional substances such as food materials. Among cooking appliances, microwave oven and refrigerator are the most innovative products with huge influences on food eating patterns as well as lifestyle. Packaging effectively reduces post-harvest preservation losses, and better packaging has technical improvements for storage and distribution. Kimchi was chosen as an example in order to study technology from the past to the present. Availability of Kimchi cabbage, enrichment of functional ingredients, identification of useful microbial species, standardization of recipe for commercialization, prevention of texture softening, introduction of salted Kimchi cabbage and Kimchi refrigerators, and packaging were reviewed. The future of traditional foods in the market will be competitive. First, traditional foods market should be maintained to protect the diversity of food materials. Secondly, tailored foods for individuals should be considered using foods with functional properties. Information on health benefits would provide insights into health and traditional food products. Third, speedy transfer of new technology to the traditional food industry is needed to ensure food quality production and new opportunities in the market. Fourth, safety of traditional foods should be ensured without sacrificing the essential characteristics of culturally important foods. Improvement of logistics, distribution, and facility should be carried out. As demand for convenience foods increases, traditional foods should be developed into products.