• Korean Journal of Microbiology
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• v.29 no.4
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• pp.263-266
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• 1991

The growth of T. novellus in auto trophic and geterotrophic media was studied to determine the time required for cells to enter stationary phase and relative percentage of ribosomal proteins. When T. novellus was grown autotrophically, growth proceeded at a slow rate characteristic of autotrophs and did not enter log phase until the end of the first day. Logarithmic growth proceeded for 3-4 days at which time the cells entered the stationary phase. In particular, logarithmic growth was accompanied by decreasing pH of culture media and in the stationary phase the pH levelled off at 6.0, a decrease of 1.6 pH value compared to original pH of media. The pH decrease was greatest during log phase when cells oxidized thiosulfate to $H_{2}$$SO_{4}$. The doubling time was about 26h. In heterotrophic media growth proceeded at a much faster rate and cells entered stationary phase 20-22h after inoculation. The doubling time was 3h. The protein content of the ribosomes in T. novellus grown heterotrophically was 4.2% greater than those from the organism grown autotrophically.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.1
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• pp.38-44
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• 2016

The quality and quantity of live food sources strongly influence the success of fish production in farming operations. Thus, critical studies of live forage species are a crucial element for progress in fish aquaculture. The fat content of food is an especially important determinant of growth in marine fish. Omega-3 highly unsaturated fatty acids (HUFA) are essential components of diet that determine the nutritional value of larval fish. Euglena is a protist that has potential as a forage species. These single-celled organisms have plant and animal characteristics they are motile, elliptical in shape and 15–500 μm in diameter. Their nutritional content is excellent, but most studies have focused on cells raised in autotrophic culture. We therefore examined differences in the lipid and fatty acid contents, and the growth of Euglena cells grown under autotrophic, heterotrophic, and mixotrophic conditions. Biomass production reached 15.03 g/L, 12.28 g/L, and 3.66 g/L under mixotrophy, heterotrophy, and autotrophy, respectively. The proportional n-3 HUFA content differed among culture methods: 10.04%, 5.80% and 10.01% in mixotrophic, heterotrophic and autotrophic cultures, respectively. Mixotrophy was to be the best form of cultivation for improving the growth and nutritional content of Euglena.

• Microbiology and Biotechnology Letters
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• v.33 no.1
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• pp.65-69
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• 2005

A bacterial strain AE-1-3, isolated from soil and wastewater identified as Pseudomonas strain, removed $NH_4^+\;and\; NO_3^-$ simultaneously in anaerobic cultivation in a medium containing $0.1\%\;NH_4NO_3\;and\;3.0\%$ glucose. The strain removed $NH_4^+\;,\;NO_3^-\;and\;NO_2^-$ completely in 15 days of anaerobic cultivation. Though N03- removed completely, $33\%\;of\;NH_4^+$ remained in 15 day of incubation in $1\%$ glucose and $0.1\%\;NH_4NO_3$ medium. The bacterium could remove $0.1\%\;NH_4NO_3$ completely in a short time by addition of $Cu^{2+},\;Zn^{2+},\;Sn^{2+}\;in\;0.5\%$ glucose medium. By chaning the metal concentration, $0.3\%\;NH_4NO_3$ could be removed completely.