• Microbiology and Biotechnology Letters
• /
• 제27권2호
• /
• pp.166-171
• /
• 1999

This study was conducted to investigate the removal rate of nitrogen and phosphorus, and lipid production from a swine wastewater by Botryococcus braunii UTEX 572 in an outdoor photobioreactor. B. braunii successfully predominated in competition with bacteria and other algae, especially Oscillatoria, which were grown spontaneously in a secondary-treated swine wastewater, under the conditions of incubation temperature at $25^{\circ}C$ and increased inoculum amount at 287mg/l. There was a significant relationship between dry weight of B. braunii and absorbance of culture solution at 680mn(r2=0.967), suggesting that the latter is as good as the former commonly used for the measurement of algal biomass which is considerably time-consuming. The removal rates of COD, TOC, total nitrogen, and total phosphorus from the swine wastewater were 33.2$\pm$2.6% and 32.8$\pm$3.2, respectively, which showing no different between them. These results suggested that the mass cultivation of B. braunii in an outdoor photobioreactor could be used for the advanced treatment of swine wastewater and lipid production.

• Journal of Microbiology and Biotechnology
• /
• 제9권3호
• /
• pp.303-310
• /
• 1999

A cost-effective mass production method for a strong antimicrobial peptide, buforin II, which was isolated from the stomach of Bufo bufo gargarizans, has been developed. This method is based on the neutralization of the positive charge of buforin II by fusion with a cysteine-rich acidic peptide (CAP) to avoid any lethal effect on the host. The neutralized fusion peptide was multimerized and expressed in Escherichia coli as tandem repeats to increase the production yield. Multimers of the CAP-buforin II fusion peptide were successfully expressed at high levels in E. coli as inclusion bodies. More than 100mg of pure buforin II was obtained per 11 of E. coli culture after cleaving the multimeric polypeptide with CNBr. The buforin II obtained from the recombinant E. coli had antimicrobial activity identical to that of natural buforin II. The proposed expression system can provide a cost-effective mass production method for both antimicrobial peptides and other host-lethal basic proteins.

• Journal of Plant Biotechnology
• /
• 제4권1호
• /
• pp.33-37
• /
• 2002

Micropropagation and adventitious root production via the culture of Polygonatum odoratum were performed. Stem segments of seedlings of Polygonatum odoratum were the most efficient explants for adventitious shoot formation compared to leaf and root segments. Exogenous cytokinin treatment was required for adventitious shoot formation. Among the cytokinin (BA, Kinetin and Zeatin) tested, BA was most effective for shoot formation from stem segments. Auxin (NAA or IBA) in combination with cytokinin significantly enhanced adventitious shoot formation. Twenty five percent of explants produced adventitious shoots on medium with 2.0 mg/L BAP alone, while 83% of explants produced adventitious shoots on medium with the combination of 2.0 mg/L BAP and 0.1 mg/L IBA. Rooting of adventitious shoots was achieved after transferring to 112 MS medium supplemented with 0.1 mg/L IBA and 0.5 mg/L zeatin. When stem segments were cultured on MS medium with various kinds of auxin (IBA, NAA and 2,4-D), adventitious roots were formed from callus. frequency of adventitious root formation was highest in 2,4-D than NAA and IBA. When roots were in clusters together with parental stem segments, growth of roots actively occurred in hormone-free MS liquid medium. The above results represent that possible application for the mass production of roots and plantlets through in vitro culture system of Polygonatum odoratum.

• Journal of Applied Biological Chemistry
• /
• 제44권2호
• /
• pp.84-86
• /
• 2001

Capsaicin synthesis by suspension cultured cells of Jalapeno pepper (Capcicum annuum L.) was assessed in vitro under various conditions including temperature (23 and $30^{\circ}C$), light intensity (with light and without light), and shaking speed (110 and 200 rpm). Capsaicin production increased, while the cell biomass growth decreased possibly due to the production of a secondary metabolite. Capsaicin synthesis was primarily affected by light condition. Cells cultivated at 110 rpm and $23^{\circ}C$ under light condition yielded the highest fresh weight, while those cultivated under the same condition, but without light resulted in the lowest cell mass. Capsaicin content in cells of 18-day-old pepper grown at 110 rpm and $23^{\circ}C$ under light was 0.125% of the cell mass. However, without light treatment, the capsaicin content in cells at the same shaking speed and temperature increased up to 169%, indicating no light is favored in the capsaicin synthesis by Jalapeno pepper. Increasing the shaking speed from 110 to 200 rpm without light enhanced the capsaicin synthesis. Results of this study demonstrate that light condition is the limiting factor in the synthesis of capsaicin in tissue-cultured Jalapeno pepper cells.

• Journal of fish pathology
• /
• 제21권3호
• /
• pp.167-174
• /
• 2008

Few studies on parasitic scutica-like ciliates (SLCs) influencing larval growth and survival during the seed production of the Japanese scallop, Patinopecten yessoensis have been performed in spite of relatively high magnitude of their infectious damage to the larvae. In the mass seed production of the scallop, SLCs were never infectious during D-larval stage which lasted 6 to 7 days. Indeed, the infection first occurred in 2 to 4 days after first umbo-staged larvae. A regular selection of active larvae in swimming behavior kept larval SLC infection low throughout the culture compared to unselected control (P<0.05) in which all the larvae alive were contained. Higher infection frequencies of the unselected control resulted in lower larval survivals and wider range of larval size distribution that drove larval attachment rate lower. To the worse, the nursery spats from the higher SLC infection exhibited a retarded growth and elevated occurrence of abnormal scallop.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• 제12권6호
• /
• pp.550-560
• /
• 2000

In order to minimize compression power and analyze the cause of exergy loss for a dry ice production cycle with 3-stage compression, the variation of compression power was investigated and the exergy analysis was peformed for the cycle. In this cycle, $CO_2$, is used both as a refrigerant and as a raw material for dry ice. The behavior of compression power and irreversibility in the cycle were examined as a function of intermediate pressure. From this result, the conditions for the minimum compression power were obtained in terms of the first stage or the third stage pressure. In addition, the irreversibilities for the cycle were investigated with respect to the efficiency of compressor. Result shows that the optimum pressure is not consistent with the conventional pressure obtained from the equal-pressure-ratio assumption. This is mainly due to the change in mass flow rate of the intermediate stage compressor by the flash gas evaporation from the flash drums. Most important is that the present exergy analysis enabled us to find bad performance components for the cycle and informed us of methods to improve the cycle performance.

• Journal of the Korea Safety Management & Science
• /
• 제20권4호
• /
• pp.1-6
• /
• 2018

Recently, bicycle has means of effective healthy transportation, and riding the bicycles is considered as popular recreational and sporting activities. Also, the saddle, steering system, driving device and braking device are researched briskly because of consumer's need for driving performance and comfort. Especially, the importance of a cassette responsible for transmission function by transmitting power to the drive shaft through the chain is very focused. The writer conducted structural analysis for the sprocket of each level using the ANSYS widely used for the analysis. Speed shifting performance was enhanced by minimization / simplification of shifting point through a sort of tooth profile of the cassette. By partitioning a clear value type and other shifting point, it has been modified to enable smooth speed-shifting. In addition, as titanium precision forming process, this study studied the molding technique by blanking and dies forging for mass production of the cassette. so it could be expected that the entire drive train would utilize that in the future. The stamping process capability for thin materials for the mass production of the sprockets is applicable to producing automobile parts, so lightweight component production is likely to be possible through that, for the safety of driving.

• Animal Bioscience
• /
• 제34권9호
• /
• pp.1532-1543
• /
• 2021

Objective: This study was aimed to establish a quantitative detection method for meat contamination based on specific polypeptides. Methods: Thermally stable peptides with good responses were screened by high resolution liquid chromatography tandem mass spectrometry. Standard curves of specific polypeptide were established by triple quadrupole mass spectrometry. Finally, the adulteration of commercial samples was detected according to the standard curve. Results: Fifteen thermally stable peptides with good responses were screened. The selected specific peptides can be detected stably in raw meat and deep processed meat with the detection limit up to 1% and have a good linear relationship with the corresponding muscle composition. Conclusion: This method can be effectively used for quantitative analysis of commercial samples.

• Journal of Applied Biological Chemistry
• /
• 제65권3호
• /
• pp.159-166
• /
• 2022

Epicoccum nigrum produces epipyrone A (orevactaene), a yellow polyketide pigment. Its biosynthetic gene cluster was previously characterized in E. nigrum KACC 40642. The YES liquid culture of this strain revealed high-level production of epicoccamide (EPC), with an identity that was determined using liquid chromatography-mass spectrometry analysis and molecular mass search using the SuperNatural database V2 webserver. The production of EPC was further confirmed by compound isolation and nuclear magnetic resonance spectroscopy. EPC is a highly reduced polyketide with tetramic acid and mannosyl moieties. The EPC structure guided us to localize the hypothetical EPC biosynthetic gene cluster (BGC) in E. nigrum ICMP 19927 genome sequence. The BGC contains genes encoding highly reducing (HR)-fungal polyketide synthase (fPKS)-nonribosomal peptide synthetase (NRPS), glycosyltransferase (GT), enoylreductase, cytochrome P450, and N-methyltrasnferase. Targeted inactivation of the HR-fPKS-NRPS and GT genes abolished EPC production, supporting the successful localization of EPC BGC. This study provides a platform to explore the hidden biological activities of EPC, a bolaamphiphilic compound.

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 한국식물생명공학회 2002년도 춘계학술대회
• /
• pp.128-128
• /
• 2002