• 한국미생물·생명공학회지
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• 제29권2호
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• pp.96-103
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• 2001

Phaffia rhodozyma is the most promising microbial source of astaxanthin production, though wild-type strains are needed to increase the astaxanthin content for commercial production. To increase astaxanthin content for commercial production, a mutant strain of P. rhodozyma was selected and culture conditions of the mutant selected were optimized. P. rhodozyma was treated with mutagenic agent such as NTG, acriflavine, and UV in serial order and carotenoids hyper-producing mutant strain was selected based on the capabilities of cell growth on the agar plate containing chemical inhibitors and carotenoids production. Among the mutants tested, a mutant WS-2 was finally selected. Mutant WS-2 produced 1.26mg carotenoids/g-dry cell weight and this value was about- 4-folds higher than that of wild-type. The optimum culture conditions were $24^{\circ}C$ of temperature, 1.5vvm of aeration and 300rpm of agitation. In the optimized condition, cell and carotenoids concentrations were 7.62g/l and 14.9mg/l, respectively.

• 대한수의학회지
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• 제36권2호
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• pp.463-470
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• 1996

The red yeast Phaffia rhodozyma, which contains astaxanthin(3, 3'-dihydroxy-$\beta$, $\beta$-carotene-4, 4'-dione) as its primary carotenoid, was tested as a dietary pigment source for egg yolks of laying hens. When the yeast was fed to laying hens at several concentrations, the intensity of redness in egg yolks was dependent on the yeast concentration in the feed and the deposition period. Addition of P rhodozyma in feed did not cause any visible adverse effect on laying hens.

• Journal of Microbiology and Biotechnology
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• 제2권1호
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• pp.46-49
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• 1992

The availability of Phaffia rhodozyma as an astaxanthin sources in the aquaculture industry is limited because of the low carotenoid content of natural isolate. In this study, we have used the protoplast fusion technique to construct cell hybrids with an increased content of astaxanthin from P. rhodozyma. Cell hybrids (F307 and F406) obtained were very stable and produced considerably more astaxanthin (> 1 mg/g yeast) than the wild parent. Karyogamy was confirmed by the isolation of recombinants after mitotic segregation of parental auxotrophic genetic markers, the increased amount of chromosomal DNA/cell and the presence of single nucleus/cell.

• 한국식품영양학회지
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• 제16권3호
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• pp.165-170
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• 2003

Astaxanthin은 수산양식에 필수적인 carotenoid 첨가물일 뿐 아니라 우수한 항암 및 항산화 물질로서 알려져 있다. 현재 astaxanthin은 P. rhodozyma에 의해 생산 할 수 있으나 P. rhodozyma에 함유된 유효성분인 astafanthin의 정량적인 분석 방법이 제시되지 못하였다. 본 연구에서는 astaxanthin에 대한 정확한 정성법과 정량분석법을 제안하였다. 이 방법은HPLC의 역상컬럼을 사용하여 dichlorornethane및 4개의 혼합 용매를 이동상으로 사용하는 것이다. 이 제시된 방법을 활용했을 때 P. rhodozyma 배양액 중의 astaxanthin의 함유량을 정확하게 검출할 수 있다. DMSO 와 acetone의 혼합용매가 최적의 astaxanthin 추출용매이었고 또한 낮은 온도와 어두운 환경 이 최적의 시료처리조건이었다.

• Journal of Microbiology and Biotechnology
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• 제5권6호
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• pp.370-372
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• 1995

A Phaffia rhodozyma chromosomal fragment (approximately 3.8 kb) capable of functioning as an origin for the replication of a kanamycin resistance ($Km^r$) plasmid in S. cerevisiae was isolated by the use of origin search plasmid, pHN134. In S. cerevisiae, transformation frequencies using the plasmid pHN134 containing an autonomously replicating sequence of P. rhodozyma was 450-580 CFU/$\mu g$ DNA. The stability of the recombinant plasmid were 16-19$\%$.

• 한국식품저장유통학회지
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• 제11권1호
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• pp.126-129
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• 2004

홍화유 저장 중 천연 항산화제의 종류별 항산화 효과를 측정하기 위하여 로즈마리 추출물, 녹차 추출물, isoflavon, Phaffia rhodozyma extract, tocopherol, sesamol 및 삽성 항산화제인 BHA를 홍화유에 첨가하여 6$0^{\circ}C$에서 한달간 저장하며 실험하였다. 저장기간중 점도의 변화 및 항산화력은 녹차 추출물>BHA>tocopherol>로즈마리 추출물>isoflavon>sesamol>Phaffia rhodozyma extract의 순이었다. 녹차 추출물이 모든 천연항산화제 중 가장 우수한 결과를 나타냈는데 실험 28일 경과 후 유지 산패의 척도인 과산화물가는 대조구에 비해 80.4%, 산가는 42.1%가 감소하였고, TBA가는 47.4%산화를 억제하는 것으로 나타났다.

• Journal of Microbiology and Biotechnology
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• 제6권2호
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• pp.103-109
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• 1996

Mn(II)+succinate decreased the carotenoid formation of the yeast Phaffia rhodozyma, probably by scavenging $O_2$. When duroquinone (DQ), an internal and external $O_2$ generator, was added to medium, P. rhodozyma produced more amount of carotenoids. The increased carotenoid production was destroyed by oxygen radical (OR) scavengers, ascorbate+Cu(II) and dimethylsulfoxide. When sub-lethal concentrations of $H_2O_2$ , an external OR source, and antimycin, an internal OR inducer, were used, the effect of $H_2O_2$ on carotenoid formation and composition was less significant than that of antimycin. Addition of superoxide dismutase, an external OR remover, rescued cells from death caused by the high concentration of DO. In this condition, the yeast culture showed an increase in carotenoid content. Addition of DQ into P. rhodozyma culture in the stationary phase did not increase carotenoid production. Therefore, carotenoid formation was stimulated by internal ORs in the growing yeast. It was probably due to release of catabolite repression on carotenogenesis in the yeast. Aeration was important for carotenoid production but was not as effective as the internal OR producer, DQ.

• Journal of Microbiology and Biotechnology
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• 제6권2호
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• pp.110-115
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• 1996

Yellow mutants of the astaxanthin producing red yeast Phaffia rhodozyma were obtained by nitrosoguanidine mutagenesis. The carotenoid composition of the yelow mutants, Yan-1 and Ny-1, was mainly $\beta$ -carotene (> 95$%$) and torulene (< 5$$). Therefore, the yellow mutants are carotene oxygenation deficient mutants (CODMs). CODMs produced decreased quantities of carotenoids compared to their red parents and this indicated that carotene may regulate its synthesis. CODMs, Yan-1 and Ny-4, on plates containing 50 $\mu$ M antimycin, showed highly pigmented vertical papillae. Antimycin-induced mutants purified from the papillae showed increases in carotenoid content (up to 1 mg $\beta$-carotene/g yeast). CODMs, Yan-1 and Ay-1, were more sensitive to antimycin than red strains, Ant-1 and 67-385. This was probably due to lower antioxidant activity of $\beta$-carotene than that of astaxanthin. Light increased torulene and light+antimycin further increased the torulene. Yan-1 and Ny-4 could grow with succinate, though their red parents, Ant-1 and Anf-1p, could not. However, antimycin induced mutation of Yan-1 or Ny-4 destroyed the ability to grow with succinate.

• 한국균학회지
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• 제21권1호
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• pp.9-15
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• 1993

Astaxanthin을 생산하는 효모 Phaffia rhodozyma로 부터 제조된 상보적 돌연변이 균주사이의 융합체에 대한 carotenoid 함량 및 성분을 분석하였으며, 몇가지 화학첨가물에 의한 이들의 색소 증진 효과를 조사하였다. 핵 융합이 확인된 융합체들은 완전배지에서 1년 또는 그 이상 계대 후에도 매우 안정 하였다. 그리고 이들의 astaxanthin 함량은 야생형 모균주의 그것에 비해 약 $2.0{\sim}3.0$배 이었다. 또한 화학첨가물(malt extract, abscisic acid, gibberellic acid, riboflavin)에 의한 색소 증진 효과는 l% malt extract와 1 mM abscisic acid 첨가시 대조구에 비교해 총 caretenoid 함량이 35%와 11%가 각각 증진되었고, 이와 반대로 5 mM gibberellic acid와 0.1 mM riboflavin첨가시 19%와 12%가 각각 감소되었다.

• Journal of Microbiology and Biotechnology
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• 제13권2호
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• pp.175-181
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• 2003

The production of a carotenoid astaxanthin, a growth-associated principal pigment, is limited in a batch cultivation, because a high glucose concentration severely inhibits the cell growth and also influences the carotenoid production. Therefore, a fermentation strategy including effective chemicals for the high-level production of cells and astaxanthin by a mutant strain Phaffia rhodozyma AJ-6-1 was developed in a fed-batch culture. First, a production medium for maximizing the cell and astaxanthin yields was formulated and optimized. Using this optimized medium, the highest cell and astaxanthin concentrations obtained were about 38.25 g/1 and 34.77 mg/1, respectively. In addition, an attempt was made to increase the amount of astaxanthin using effective chemicals such as ethanol and acetic acid, which are known at an inducer and/or precursor of carotenoid synthesis. When either 10g/1 ethanol or 5 g/1 acetic acid was added to investigate the resulting astaxanthin content, a relatively high astaxanthin concentration or 45.62 mg/l and 43.87 mg/1, respectively, was obtained, and the cell concentrations also increased slightly under these conditions. Therefore, these results imply that a fed-batch culture of the mutant strain P. rhodozyma AJ-6-1 could be effectively employed in the commercial production of astaxanthin, although the factors affecting the productivity remain to be elucidated.