• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.4
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• pp.403-405
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• 1984

Since chlorella was found to be a source of protein in 1974, wide ranges of investigations on culture methods, its constituents and nutritional factors have been carried out, i. e. most of them were the reports on the nutritional evaluation. However, kinetics such as absorption, distribution, metabolism and elimination of chlorella protein have not been fully elucidated. So, on the assumption that using $N^{15}$ labelled chlorella protein could accomplish good results for kinetics of chlorella in in vivo experiments, $N^{15}$ was added to the culture fluid. From the result of this study, it is suggested that chlorella utilizes N as well as $N^{15}$ in protein synthesis, and this $N^{15}$ labelled chlorella protein can be useful tool for the study of kinetics of chlorella in in vivo experiments.

• Preventive Nutrition and Food Science
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• v.15 no.4
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• pp.282-286
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• 2010

To isolate a calcium-binding peptide from chlorella protein hydrolysates, chlorella protein was extracted and hydrolyzed using Flavourzyme, a commercial protease. The degree of hydrolysis and calcium-binding capacity were determined using trinitrobenzenesulfonic acid and orthophenanthroline methods, respectively. The enzymatic hydrolysis of chlorella protein for 6 hr was sufficient for the preparation of chlorella protein hydrolysates. The hydrolysates of chlorella protein were then ultra-filtered under 5 kDa as molecular weight. The membrane-filtered solution was fractionated using ion exchange, reverse phase, normal phase chromatography, and fast protein liquid chromatography to identify a calcium-binding peptide. The purified calcium-binding peptide had a calcium binding activity of 0.166 mM and was determined to be 700.48 Da as molecular weight, and partially identified as a peptide containing Asn-Ser-Gly-Cys based on liquid chromatography/electrospray ionization tandem mass spectrum.

• Journal of Plant Biology
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• v.29 no.3
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• pp.145-156
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• 1986

The excretion of ammonia and glutamine synthetase activities were measured in aposymbiotic Paramecium and symbiotic Paramecium. The uptake of nitrate and ammonia, and specific enzyme activities of nitrate reductase, glutamate dehydrogenase and glutamine synthetase were investigated in symbiotic Chlorella from Paramecium bursaria and Chlorella ellipsoidea. The ammonia concentration in the culture media of aposymbiotic Paramecium was increased according to the growth of the Paramecium but it was not changed in symbiotic Paramecium. Nitrate, the major nitrogen source, was taken up at a rate of 0.635 nmol/ 106 Chlorella/hr in Chlorella ellipsoidea. Most of ammonia was assimilated to glutamine by glutamine synthetase, of which acitivty was 1,467 $\mu$mol/mg protein/min in Chlorella elliposidea. Contrary to Chlorella ellipsoidea, ammonia and glutamine transported from the Paramecium were the nitrogen source of symbiotic Chlorella and ammonia was taken up at a rate of 3.854 nmo./106 Chlorella/hr into synmbiotic Chlorella. Most of ammonia were assimilated to glutamate by glutamate dehydrogenase in symbiotic Chlorella. The glutamate dehydrogenase (GDH/NADH) activity was 0.851 $\mu$mol/mg protein/min.

• Journal of the Korean Society of Food Science and Nutrition
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• v.2 no.1
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• pp.35-40
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• 1973

Though many papers have reported the nutrition value of Chlorella their results are all different because of the differences in processing method. To investigate its processing and nutrition value we provided the white rats with the Chlorella that were treated with boiling methanol. The results obtained in this investigation are summarized as follows: Two groups. which were fed with 20% Chlorella protein and 10% Chlorella plus 0.37% $_{DL}-methionine$ gained less weight than the 10% egg protein group but equaled the 20% egg protein group in weight gain. The digestion rates calculated from ordinary N-balance method were 83.6% for 20% Chlorella, 81.7% for 10% Chlorella, and 84.9% for 10% Chlorella plus methionine group. This value is lower than 20% Egg (93.8%) and 10% Egg group (89.6%) Biological values from this method were 78.3% for 20% Chlorella and 79.1% for 10% Chlorella group, being lower than 20% Egg (85.2%), 10% Egg (93.2%). But the biological value of 10% Chlorella group was markedly enhanced to 92.2%, a value comparable to that of 10% Egg group, by adding methionine.

• Korean Journal of Microbiology
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• v.2 no.1
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• pp.1-11
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• 1964

Yung Nok Lee (Dept. of Biology, Korea University) : Studies on the phosphate metabolism in Chlorella, with special reference to polyphosphate. Kor. J. Microbiol., Vol.2, No.1, p1-11 (1964). 1. Uniformly $^{32}P$-labeled Chlorella cells which were irradiated with Cobalt-60 gamma-rays of about 70, 000 $\gamma$ dose, were further grown in a standard "cold" medium ("hot".rarw."cold"), and some portions of the algae were taken out at the begining of, and at intervals during the culture, and subjected to analyze the contents of $^{32}P$- and total P in various fractions of the cell materials. Results obtained were compared with those of nonirradiated normal cells. 2. Amounts of phosphate in various fractions of the nonirradiated normal Chlorella cells were measured using uniformly $^{32}P$--labeled cells. Analysis of the $^{32}P$--labeled algal cells showed that the highest value in P-content was the fraction of RNA followed by those of lipid, polyphosphate "C" polyphosphate "B", DNA, nucleotidic labile phosphate compounds, polyphosphate "A" and protein. It was observed that content of total polyphosphates in a single Chlorella cell was almost equal to RNA-P content in the cell, and the amount of RNA-P was almost equal to ten times of DNA-P content. 3. When the $^{32}P$--labeled algae which were irradiated with gamma-rays were grown in a normal "cold" medium, phosphate contents in the fraction of DNA, nucleotidic labile phosphate compounds and protein decreased markedly, while the contents of phosphate in the fractions of polyphosphate "C" and potyphosphate "B" increased in comparison with those of unirradiated normal cells. So, it was considered that the pretreatment of above mentioned dose of gamma-ray inhibited DNA and protein synthesis from polyphosphate in Chlorella cells. 4. Proceeding the culture of $^{32}P$--labeled Chlorella in a "cold" standard medium, whose synthetic activity of DNA and protein from polyphosphate was disturded by gamma-ray irradiation, the amounts of $^{32}P$-in the fraction of polyphosphate "C" increased, in contrast with those of polyphosphate "B" fraction. According to these experimental results, it was inferred that polyphosphate "B" could transform into polyphosphate "C" in normal growing Chlorella cells.sults, it was inferred that polyphosphate "B" could transform into polyphosphate "C" in normal growing Chlorella cells.ing Chlorella cells.

• Journal of Plant Biology
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• v.9 no.1_2
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• pp.1-6
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• 1966

Using the Chlorella cells which had been uniformly labeled with $^{32}P$, the distribution of phosphorus in various fractions of cell material was investigated. Uniformly $^{32}P$-labeled Chlorella cells were further grown in a P-free medium, and some protions of the cells were taken out at intervals during the culture, and subjected to analyze the contents of $^{32}P$ in various fractins of the cell constituents. 2. Analysis of the $^{32}P$-labeled Chlorella cells showed that the highest in P-content was the fraction of RNA followed by those of lipid, RNA-polyphosphate complex, acid-insoluble polyphosphate, acid-soluble polyphosphate, DNA and protein. 3. During the culture of $^{32}P$-labeled Chlorella cells in a P-free medium, amounts of phosphate in DNA, protein and lipid fractions increased, while the P-contents in the fraction of RNA-polyphosphate complex decreased as well as those of acid-insoluble polyphosphate and acid-soluble polyphosphate fractions. 4. It was inferred that phosphorus used in the syntheses of DNA and protein was taken from polyphosphates of the cells, and RNA-polyphosphate complex would play an important role as a phosphate pool.

• Korean Journal of Microbiology
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• v.10 no.3
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• pp.117-127
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• 1972

To study the effect of IAA on the growth of Chlorella, the alage wre cultured on the media for six days by bubbling $_{2}$ enriched air under 10K lux at 20-$25^{\circ}C$. The culture media were made by adding a concentration of $10^{-3}$M, $10^{-4}$M, and 0M(as a control) IAA to the standard media. During the period of culture, Chlorella was smapled for the given time of interval and photosynthetic and respiratory activities were measured by Warburg manometer and change of chemical components of Chlorella was determined by spectrophotometry after the Chlorella cell was fractionated by Schmidt-Thannhauser method. 1) Photosynthetic and respiratory activities were enhanced by IAA ; especially the enhancement of respiratory activity was so remarkable. 2) As to the chemical components of Chlorella, carbohydrates and amino acids were reduced a little but phosphate, RNA, DNA, and protein were increased by $10^{-3}$M IAA ; the increase of RNA, in particular, was noticable. 3) The above results suggest that the enhancement of growth of Chlorella, by IAA and ATP induced by respiratory activity accelerated with IAA enhanced RNA synthesis, resulting in an increase of protein synthesis.

• Journal of Nutrition and Health
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• v.9 no.2
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• pp.98-101
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• 1976

The essential amino acids composition of Green algae (chlorella ellipsoidea) that was isolated near the suwon was compared with that of soy flour and the provisional pattern of amino acids of reference protein of FAO and found that the limit amino acid was methionine. The rest of essential amino acids were distributed widely and abunduntly. While soy flour was defficient in methionine and valine on comparing with the provisional pattern. Slightly more content of methionine was recognized in chlorella protein than that of spirulina maxima which was reported to be eaten in the Lake Chard region of Africa and Mexico as a daily food. It was concluded that good quality protein is able to be synthesised from the wild alage if a qualified alage media was given to them.

• Korean Journal of Microbiology
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• v.19 no.1
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• pp.8-13
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• 1981

The content of sulfhydryl compounds in Chlorella cells during the life cycle in the synchronous culture is determined spectrophotomatically at 250nm(pH7.0) using p-CMB as SH-reagent. The changes in the content of-SHl compounds and protein in Chlorella cells is measured during the life cycle in connection with cell division and analyzed. 1) The amounts of total ninhydrin reactive substance increased with growth of cells but increased the more at the $L_4$ stage(cytokinesis stage) than at the $L_2$ stage (nuclear division stage). 2) The sulfhydryl content of Chlorella cells increased strikingly at the $L_2$ stage and decreased markedly at the $L_4$ stage. 3) The amounts of values -SH/protein showed a peak at the $L_2$ stage. The increase of the amount of total-SH compounds of cells during the nuclear division period was considered to be caused by the weighty roles of protein-SH groups for the formation of nuclear division apparatus and for the enzyme activity.

• The Plant Pathology Journal
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• v.21 no.1
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• pp.13-20
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• 2005

Chlorella viruses are large icosahedral, plaque-forming, dsDNA viruses that infect certain unicellular, chlorellalike green algae. The genomic DNA of over 300 kb contains many useful genes and promoters. Over 40 chlorella viruses have been isolated from fresh water in Korea since 1998. The viruses were amplified initially in chlorella strain NC64A, and pure isolates were obtained by repeated plaque isolation. SDS-PAGE analysis revealed similar but distinct protein patterns, both among the group of purified viruses and in comparison with the prototype chlorella virus PBCV-1. Digestions of the 330- to 350-kb genomic DNAs with 10 restriction enzymes revealed different restriction fragment patterns among the isolates. The tRNA-coding regions of 8 chlorella viruses were cloned and sequenced. These viruses contain 14-16 tRNA genes within a 1.2- to 2-kb region, except for the SS-1 isolate, which has a 1039-bp spacer in a cluster of 11 tRNA genes. Promoter regions of several early genes were isolated and their activities were analyzed in transformed chlorella. Some promoters showed stronger activity than commonly used CaMV 35S promoter and chlorella transformation vectors for heterologous protein are beings constructed using these promoters.