• Fisheries and Aquatic Sciences
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• 제14권4호
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• pp.317-322
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• 2011

This study was conducted to develop economical agricultural fertilizer media for the mass culturing of Nannochloropsis oceanica. Specific growth rates of N. oceanica cultured with differing concentrations of commercial compounds, urea fertilizers, and trace elements (Zn, Cu, Co, Mo) were compared with the growth rate in f/2 medium. Among the various added trace elements, $CuSO_4{\cdot}5H_2O$ was most effective for high growth of N. oceanica. The main nitrogen source in the agricultural fertilizers was ammonium, which was unsuitable for the growth of N. oceanica. Thus, the fertilizer at a lower concentration infused with $NaNO_3$ as a nitrogen source was more effective than fertilizer at higher concentrations. In this study, the growth of N. oceanica cultured with an agricultural fertilizer medium composed of compound fertilizer (41.7 mg/L), urea fertilizer (34.4 mg/L), $NaNO_3$ (150 mg/L), and $CuSO_4{\cdot}5H_2O$ (0.0588 mg/L) was similar to that of N. oceanica cultured in f/2 medium.

• Journal of Microbiology and Biotechnology
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• 제32권4호
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• pp.397-404
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• 2022

Natural killer (NK) cell activity is more attenuated in hepatocellular carcinoma (HCC) patients than normal. Hypoxic-inducible factor (HIF)-1α is highly expressed in tumors to maintain their metabolism in a hypoxic environment. The expression of HIF-1α in cancers can lead to cell growth, proliferation, invasion/metastasis and immune escape. Although apigenin, a flavonoid, is known to have various biological activities, it has not been demonstrated in NK cell immune activity in HCC cells. In this study, NK-92 cells were directly cocultured with HCC SK-Hep1 cells for 24 h to evaluate NK cell activity in HCC cells or HCC cells expressing HIF-1α by apigenin. NK cell cytotoxicity to HCC cells expressing HIF-1α was significantly increased, and NK cell-activating receptors, NKG2D, NKp30 and NKp44 were highly expressed. The activating effect of apigenin on NK cells substantially induced apoptosis in HCC cells expressing HIF-1α through high expression of CD95L on the surface of NK-92 cells. Moreover, apigenin excellently inhibited the level of TGF-β1 in a coculture of NK cells and HCC cells. In conclusion, apigenin seems to be a good compound that increases NK cell cytotoxicity to HCC cells by controlling HIF-1α expression.

• 한국식품과학회지
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• 제46권6호
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• pp.762-768
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• 2014

본 연구에서는 oleic acid로 유도시킨 비알코올성 지방간 HepG2 세포 모델을 활용하여 LAFGE의 비알코올성 지방간 개선 효과를 검토하고 RT-PCR과 Western blot으로 메카니즘을 해석하였다. LAFGE는 1 mg/mL 농도에서 NFGE보다 세포 내 지방축적을 약 1.5배 저해하였다. Fig. 5에 나타낸 바와 같이 LAFGE는 FAT/CD36 mRNA 발현을 감소시켜 세포 내로 유입되는 지방산의 양을 감소시켰으며, $PPAR{\alpha}$와 CPT-1의 mRNA 발현을 증강시킴으로써 지방산의 베타-산화를 촉진시켰다. 또한 LAFGE는 지방합성을 촉진하는 전사인자인 SREBP-1c와 그의 조절을 받는 FAS의 mRNA 발현 수준을 oleic acid 처리시보다 각각 51%와 35%까지 크게 감소시켰다. 뿐만 아니라 LAFGE는 농도의존적으로 SREBP-1c와 FAS의 단백질 발현도 감소시켰다. 이 결과들은 LAFGE가 oleic acid처리에 의해 유도된 HepG2 세포 내의 지방축적을 개선할 수 있음을 시사하였다.

• 생명과학회지
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• 제26권7호
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• pp.847-854
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• 2016

Nucleoside adenosine 유도체의 하나인 cordycepin (3′-deoxyadenosine)은 Cordyceps 속에서 유래된 활성 물질 중의 하나로서 항염증, 항산화 및 항암활성을 포함한 다양한 약리학적 효능이 있는 것으로 잘 알려져 있다. 본 연구에서는 AGS 인체 위암세포의 증식에 미치는 cordycepin의 영향과 관련 기전 연구를 시도하였다. Cordycepin의 처리에 따라 AGS 세포의 생존율이 처리 농도 의존적으로 감소되었으며, DNA 단편화 및 flow cytometery 분석에 따른 apoptosis 유발 또한 유의적으로 증가하였음을 확인하였다. 이러한 cordycepin 처리에 따른 AGS 세포의 apoptosis 유도에는 TRAIL, DR5 및 FasL의 mRNA 및 단백질의 발현 증가가 연관되어 있었다. 아울러 cordycepin은 Bcl-2 family 중 pro-apoptotic 인자인 Bax의 발현은 증가시켰으며, anti-apoptotic 인자인 Bcl-2 및 Bcl-xL의 발현은 전사 및 번역 수준에서 억제시켰다. 이러한 현상들은 extrinsic 및 intrinsic apoptosis의 initiator caspase (caspase-8 및 -9) 뿐만 아니라 effector caspase인 caspase-3의 활성과 PARP 단백질의 절단 증가와 연관성이 있었다. 따라서 AGS 세포에서 cordycepin에 의한 apoptosis의 유발은 death receptor 활성과 mitochondria 기능 손상을 포함한 multiple apoptotic pathway가 관여할 것으로 생각된다. 비록 좀 더 세심한 기전 연구의 결과가 뒤따라야 되겠지만, 본 연구의 결과는 cordycepin의 항암작용을 이해하는데 중요한 자료가 될 것이며 향후 수행될 추가 실험을 위한 기초 자료로서 그 가치가 매우 높을 것으로 생각된다.

• Fisheries and Aquatic Sciences
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• 제8권3호
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• pp.118-121
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• 2005

Arylsulfatase cloned from a marine bacterium, Pseudoalteromonas carrageenovora, was over-expressed in Escherichia coli. Most of the recombinant arylsulfatase was found in the cell lysate with induction up to $10{\mu}M$ IPTG. However, enzyme activity was observed both in the culture supernatant and cell lysate by induction with IPTG concentration of $50-5,000{\mu}M$. Most of the recombinant enzyme was localized in the periplasmic space with $10{\mu}M$ IPTG induction, while half of the enzyme was distributed in the periplasmic space with $50{\mu}M$ IPTG induction. Cell growth and arylsulfatase activity did not change with the induction time, and the level of recombinant arylsulfatase expression was maintained at 4-5 U/mL after 6 to 14 hr of culture.

• Fisheries and Aquatic Sciences
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• 제9권3호
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• pp.123-128
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• 2006

An epizootic causing mortality among cultured marine finfishes occurred in 1999 in the province of Kyoungsang, Korea. The disease was characterized by the presence of enterocele, abdominal swelling, and gastroenteritis. The causative bacteria were isolated from olive flounder (Paralichthys olivaceus), black rockfish (Sebastes schlegeli), turbot (Scophthalmus maximus) and the rearing water. These bacteria showed swarming activity on agar plates and yellowish or greenish colonies on thiosulfate-citrate-bile salts-sucrose (TCBS) agar plates, but no luminescence. The pathogen was identified as Vibrio harveyi based on morphological and biochemical characteristics and the sequence of l6S rDNA. The lethal doses (LD$_{50}$) of olive flounder and black rockfish were estimated to be $1.24\times10^6-1.36\times10^8$ and $3.24\times10^5-5.8\times10^7$ CFU/fish respectively following intraperitoneal injection.

• Fisheries and Aquatic Sciences
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• 제11권4호
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• pp.219-223
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• 2008

To increase the level of $CoQ_{10}$ production in mass culture, the effects of pH and light irradiation on $CoQ_{10}$ production by Rhodobacter sphaeroides were investigated in a 1-L bioreactor. $CoQ_{10}$ production was growth-associated, and the highest production of $CoQ_{10}$ (1.69 mg/g dry cell) was obtained under uncontrolled pH: this production was 1.7 times higher than that obtained at controlled pH 7. Therefore, pH was a key factor affecting $CoQ_{10}$ production. The effect of light irradiation on $CoQ_{10}$ production was negligible. This result offers an advantage for mass production of $CoQ_{10}$.

• Fisheries and Aquatic Sciences
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• 제17권2호
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• pp.269-273
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• 2014

Coralline algae, the algal whitening phenomenon-causing seaweeds, are characterized by calcareous deposits in the cell wall. The viability of the coralline algae Lithophyllum yessoense and Corallina pilulifera was quantitated using a triphenyltetrazolium chloride assay and eight calcification inhibitors. Among these inhibitors, ferric citrate showed the strongest inhibition of coralline algae viability. The concentrations of ferric citrate conferring 50% inhibition were 1.7 and 3.8 mM for L. yessoense and C. pilulifera, respectively. Thus, at a specific concentration and in a localized area, ferric citrate may be used to prevent the blooming of coralline algae.

• Fisheries and Aquatic Sciences
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• 제8권3호
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• pp.122-127
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• 2005

A DNA chip that rapidly and accurately detects the viral genes in rhabdovirus-infected fish was developed. The N, Ml, and G proteins of three rhabdovirus strains, infectious hematopoietic necrosis virus (IHNV), viral hemorrhagic septicemia virus (VHSV), and flounder rhabdovirus (HIRRV), were selected for use as probes. The sequences of the corresponding genes were obtained, and probes were prepared by PCR using specific primer sets. The specificity of the probes was confirmed by cross PCR. The prepared probes were spotted on poly-L-lysine- or aminosilane-coated glass slides and hybridized with target DNA under several different conditions in order to determine the optimal hybridization temperature, glass-slide coating, and target cDNA concentration.

• Fisheries and Aquatic Sciences
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• 제15권3호
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• pp.209-213
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• 2012

Members of the ciliate group of protozoans are often observed in mass cultures of rotifers. In particular, Euplotes and Vorticella are common contaminating species. In this study, I examined the effect of the ciliates Euplotes sp. and Vorticella sp. on the growth of the rotifer Brachionus rotundiformis by conducting inter-specific and tripartite-specific mixed-culture experiments. The growth of rotifers was suppressed in co-existence with Euplotes sp. compared with monocultures of rotifers. However, Vorticella sp. promoted rotifer growth. Moreover, Vorticella sp. improved the growth of rotifers suppressed by Euplotes sp. contaminants. In 5-L semi-mass cultures of rotifers, growth of the contaminating protozoan Euplotes sp. was heavily suppressed by Vorticella sp. The stable maintenance of the rotifer culture ecosystem can be achieved by manipulating the types of contaminating protozoan species.