• 한국가금학회지
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• 제25권2호
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• pp.79-89
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• 1998

Dietary levels of single cell protein(SCP) 0 %, 5 %, 10 % and 15 % were included in experimental diets. The purpose of this experiment is to examine the effects of diets containing different levels of SCP on the performance of broiler chicks, including the nutrient availabilities, compared to that of the commercial diet. In order to evaluate the nutritive value of SCP, feeding and metabolism trial were conducted with a total of 160 broiler chicks for a period of 4 weeks. Contents of CP and pure protein in the composition of SCP were 67 % and 32. 05 %, respectively. In general, diets with over 10 % SCP substitution had significantly decreased body weight gain compared to the control diet. Feed intake of chicks fed SCP supplemental groups was significantly decreased compared to that of control, especially observed the significant difference in proportion to increas mg the levels of SCP. The feed efficiency was decreased by the addiition of SCP, but was not significantly different between control and SCP supplemental groups. The digestibilities of DM, CP and NFE tended to be similar among treatments, whereas crude fiber treated with SCP tended to be lower digestibility than control. In conclusion, the optimum dietary supplemental SCP would be less 5 % for broiler growth in this experiment.

• Journal of Nutrition and Health
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• 제12권2호
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• pp.87-93
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• 1979

인구적 증가와 사료 가격의 상승으로 인한 육류 제품의 가격이 상승하고 있음은 우리나라를 비롯하여 세계적인 현황이다. 이 문제에 대처하는 한 방법으로 새로운 단백질 급원으로써 Single Cell Protein이 개발되었고 이에 대한 여러가지 연구가 되어지고 있다. Single Cell Protein이 인간에게 식용이 될 동물이나 나아가서는 인간에게 직접 식품으로 사용되기 전에 인체나 동물 체내에 끼칠 영향과 그 안전성을 확인하려는 하나의 노력으로 이 연구가 시도되었다. 동물 체내 대사에 미치는 SCP의 악영향의 주원인은 함유된 독성물질로 보고 그 독성물질이 SCP 생산 및 처리 과정 중 어느 시기에 생겨나는가를 규명해 보고자 하였다. Fermentation을 끝낸 SCP의 Supernatant내에 함유된 Inorganic phosphate(I.P.)의 함량을 측정하여 SCP세포의 Viability를 알아보았다. Fermentation을 끝낸 후 10일까지는 I.P.가 차츰줄다가 40일이 지났을 때에는 I.P.의 증가를 보였으나 직후보다는 낮음을 나타냈다. 또한 냉동 건조시킨 뒤에도 SCP Cell이 살아있음을 보였다. 또한 위와 관련지어서 SCP를 Protein급원으로 써서 사육한 흰쥐에 나타난 Protein Efficiency Ratio(PER)를 통하며 SCP의 질을 평가하였다. 실험결과로 나타난 것을 보면 표준 식이에 사용된 Casein의 PER$(\overline{X}=2.58)$이 SCP의 PER$(Dict 1;\overline{X}=0.888$, $Dict 2;\overline{X}=0.893$, $Dict 3;\overline{X}=0.860)$ 보다 유의적으로 높았다. 그리고 총실험기간의 평균치를 볼 때, Fermentation을 끝내고 3일 후와 6일 후에 냉동 건조시킨 SCP의 PER은 시판되는 SCP의 것과 별다른 차이를 보이지 않았다. 그리나 후반기에 있어서는 Fermentation을 끝내고 3일과 6일 후에 냉동 건조시킨 SCP의 PER이 시판되는 SCP의 것보다 약간 저조함을 보였다. 그리고 Casein의 PER은 총 사육기간은 통하여 별 변동이 없음에 반하여 후반기에 SCP의 PER이 급격한 저하를 보임은 SCP 사용상의 문제점을 나타낸 것으로 해석 된다.

• 한국환경보건학회지
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• 제22권2호
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• pp.10-18
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• 1996

Experiments were carried out to find the possibility of an economic production of single cell protein(SCP) in mixed culture by Cellulomonas sp. KL-6 and a second organism. The second organism, strain LI-10, was isolated from the large intestines of a mouse. 1. When these strains were mixed, cell growth and carboxymethyl cellulase (CMCase) activity were increased to about 63% and 161%, respectively compared with that of single culture of strain KL-6. We found the mixed culture as a proper method of degradation of cellulose in our study. 2. Strain LI-10 was identified as E. coli. 3. This strain produced trace amounts of cellobiose, but glucose was not found in detectable amounts in the filter paper(FP) medium. 4. $CaCO_3$ injected in the medium at the ratio of 0.1% not only enhanced cell growth but also was effective as an acid neutralizing agent. 5. When this organism was cultured under the optimal medium (glucose 0.1%, $NH_4Cl$ 0.1%, yeast extract 2.0%, $KH_2PO_4$ 0.1%, KCl 0.05%, pH 7.2 and a temperature 30$\circ$C) for 5 days, a cell mass produced 1.18 g/l. The results showed the increase of cell mass up to 300% compared to 0.28 g/l produced in CMC medium.

• 한국미생물·생명공학회지
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• 제17권6호
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• pp.556-562
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• 1989

The bioconversion of mandarin orange peel press liquor to single cell protein (SCP) by two yeast strains, F-60, and C-7, which were isolated from mandarin orange peel was carried out and compared with that of using Candida utilis IFO 0598. Experiments were directed toward the high yield of biomass and high protein in cultures of the strains mentioned above. Candida utilis IFO 0598, F-60 and C-7 strains were cultivated at 3$0^{\circ}C$, pH 5.2 for 3 days in shaking flasks. The effects of some nutrients on cell growth were studied. Cell mass and protein content per cell mass were increased by addition of urea 1%, KH$_2$PO$_4$ 0.1% and MgSO$_4$ㆍ7$H_2O$ 0.05%, When the F-60 strain cultured under the optimal conditions, cell mass, growth yield and protein content were 41.2g/l, 53.9%, 59.7%, respectively. Cell mass was also increased up to 15% by modifying the fermentation condition on the bench type 20l jar fermentor. Crude fat content (10.3%) of dried C-7 cell was higher than those of C. utilis and F-60, 4.9% and 5.6% respectively. Total protein content of the F-60 strain was 59.7% per dry weight. And we compared their amino acid compositions with that of FAO provisional pattern. In the case of the F-60 strains, amino acid contents such as lysine, leucine and isoleucine were much higher than those of methionine, cystine and tryptophan.

• Animal Bioscience
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• 제34권12호
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• pp.1951-1962
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• 2021

Objective: This study was conducted to evaluate single cell protein (SCP), produced from Methylococcus species, as a protein source on the growth performance, carcass traits and gut health of broiler chickens. Methods: Ten iso-nitrogenous and iso-caloric diets containing 0 (Control), 2.5%, 5%, 7.5%, and 10% SCP replacing either soybean meal (T₁ to T₅) or fish meal (T₆ to T₁₀) were formulated. Each diet prepared for starter (0 to 14 days), grower (15 to 21 days), and finisher (22 to 42 days) phases was offered to four replicates of 10 chicks each (n = 400). Growth performance at different phases and carcass characteristics and intestinal morphology on 42nd day of trial were measured. Results: Body weight gain in groups fed 2.5% and 5% SCP diets were comparable to control during different phases and cumulatively, however lower (p<0.01) in 7.5% and 10% SCP diets. Feed conversion ratio was better (p<0.01) in 2.5% and 5% SCP diets. Dressing percentage, abdominal fat percentage and meat:bone ratio were not affected (p>0.05) by SCP inclusion in the diets. However, breast percentage was higher (p<0.01) in 2.5% and 5% SCP groups and thigh percentage higher in 7.5% and 10% SCP groups. Total microbial count in duodenum, jejunum and ileum were not affected (p>0.05) by SCP inclusion up to 10% in diets. Duodenal villi length and crypt depth were highest (p<0.01) in group fed 5% SCP diets and lowest in group fed 10% SCP diets. Jejunal villi length and crypt depth as well as ileal villi length were lowest (p<0.01) in group fed 10% SCP diets. Body weight gain, feed consumption, feed conversion ratio and gut health were better (p<0.01) in broilers fed fish meal based diets compared to soybean meal based diets. Conclusion: It was concluded that inclusion of SCP up to 5% replacing soybean meal in broiler diets is beneficial in improving growth rate, breast yield and gut health status.

• Journal of Microbiology and Biotechnology
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• 제34권9호
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• pp.1912-1918
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• 2024

Single-cell protein (SCP) derived from microorganisms is widely recognized as a viable alternative protein source for the future. Nevertheless, the commercialization of yeast-based SCP is hampered by its relatively low protein content. Therefore, this study aimed to enhance the protein content of Saccharomyces cerevisiae via random mutagenesis. To achieve this, S. cerevisiae KCCM 51811, which exhibited the highest protein concentration among 20 edible S. cerevisiae strains, was selected as a chassis strain. Subsequently, a KCCM 51811 mutant library was constructed (through UV irradiation) and screened to isolate mutants exhibiting high protein content and/or concentration. Among the 174 mutant strains studied, the #126 mutant exhibited a remarkable 43% and 36% higher protein content and concentration, respectively, compared to the parental strain. Finally, the #126 mutant was cultured in a fed-batch system using molasses and corn-steep liquor, resulting in a protein concentration of 21.6 g/l in 100 h, which was 18% higher than that produced by the parental strain. These findings underscore the potential of our approach for the cost-effective production of food-grade SCP.

• Applied Biological Chemistry
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• 제30권3호
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• pp.258-263
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• 1987

절간고구마 주정폐액은 여과가 용이하고, 유기질 함량이 높으며 pH가 효모의 생육에 적합하여 미생물의 단세포 단백질(single cell protein) 생산을 위한 기질로 적합하였다. 본 실험에 사용한 Candida boidinii는 토양으로부터 분리된 고구마 주정폐액 자화성이 가장 우수한 균주로서, 72시간 배양하였을 때 배지 100ml당 1.02g의 건조균체량을 얻을 수 있었으며, 이 때의 조단백질 함량은 54.5%였다. 효모의 생육은 pH 5.0과 $30^{\circ}C$에서 72시간 배양하였을 때 최대에 달하였고 urea 0.2%와 무기염류를 첨가하면 생육이 촉진되었다.

• Journal of Microbiology and Biotechnology
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• 제33권12호
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• pp.1648-1656
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• 2023

We have previously observed that feeding with single-cell hemoprotein (heme-SCP) in dogs (1 g/day for 6 days) and broiler chickens (1 ppm for 32 days) increased the proportion of lactic acid bacteria in the gut while reducing their body weights by approximately 1~2%. To define the roles of heme-SCP in modulating body weight and gut microbiota, obese C57BL/6N mice were administered varied heme-SCP concentrations (0, 0.05, and 0.5% heme-SCP in high fat diet) for 28 days. The heme-SCP diet seemed to restrain weight gain till day 14, but the mice gained weight again later, showing no significant differences in weight. However, the heme-SCP-fed mice had stiffer and oilier bodies compared with those of the control mice, which had flabby bodies and dull coats. When mice were dissected at day 10, the obese mice fed with heme-SCP exhibited a reduction in subcutaneous fat with an increase in muscle mass. The effect of heme-SCP on the obesity-associated dyslipidemia tended to be corroborated by the blood parameters (triglyceride, total cholesterol, and C-reactive protein) at day 10, though the correlation was not clear at day 28. Notably, the heme-SCP diet altered gut microbiota, leading to the proliferation of known anti-obesity biomarkers such as Akkermansia, Alistipes, Oscillibacter, Ruminococcus, Roseburia, and Faecalibacterium. This study suggests the potential of heme-SCP as an anti-obesity supplement, which modulates serum biochemistry and gut microbiota in high-fat diet-induced obese mice.

• 한국미생물·생명공학회지
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• 제7권4호
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• pp.211-216
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• 1979

단세포 단백질의 합성이나 환성오니법에 의한 폐수처리 등에 응용되고 있는 Air-lift Fermentor (ALF)는 일반적인 기계식 교반 발효조에 비하여 산소전달 효과가 우수한 것으로 알려져 있다. 그러나 미생물의 성장반응에는 적절한 교반이 필요하므로 발효조 내에서는 높은 산소 농도와 함께 활발한 교반이 이루어져야 한다. 본 연구에서는 ALF 내에서의 산소전달에만 국한해오던 연구 방향에서 실제로 Methylomonas, sp를 이용한 methanol fermentation을 행하여 이 발효조의 기능을 조사하였다. 그 결과 교반은 활발히 일어나고 있으나 높은 농도의 산소를 얻기 위해서는 높은 압력하에서나 낮은 dilution rate에서 운전하여야 하는 것으로 나타났다.

• Applied Biological Chemistry
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• 제38권6호
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• pp.496-501
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• 1995

Cellulomonas sp. KL-6 균주의 균체내 외 단백질은 배양 5일째에 $266\;{\mu}g/m{\ell},\;37\;{\mu}g/m{\ell}$로 가장 많이 생산하였다. 본 실험에서 사용한 KL-6 균주는 볏짚을 분쇄 후 1.0% NaOH와 10% $NH_4OH$로 $80^{\circ}C$에서 30분간 처리한 후 $H_3PO_4$로 중화하여 탄소원으로 이용하였을 때 각각 $1.63\;g/{\ell}$ 및 $1.47\;g/{\ell}$의 SCP가 생산되어 처리하지 않은 볏짚의 $0.5\;g/{\ell}$ 보다 균체수율이 증가되었다. KL-6 균주가 생산한 SCP의 필수아미노산의 함량이 FAO 표준단백질에 비해 많아 영양적 가치가 매우 우수하였다. 그러나 실제 동물사육에 이 균체를 이용코저 할 때는 균체의 세포벽을 파쇄후 사용해야 되리라 사료된다.