초록 ▼

○ 연구결과
- 우수종균을 사용하여 미생물 대사공학 기법으로 김치발효시스템을 조절한 결과 김치발효환경내의 종균 점유율(80% 이상)이 탁월하였으며, 김치 상미기간을 약 4개월간 유지함으로서 김치품질의 균일화 및 보존성을 향상시킬 수 있었고 종균에 의한 김치발효 맛을 다양화할 수 있었다.
- Bifidobacteria을 이용한 김치 섭취 시 변비개선 및 장내 미생물 균총 개선효과가 있었으며, 우량종균김치와 비피더스종균김치의 안정성실험 결과 무독하였고 항산화작용 및 HDL-콜레스테롤농도비를 증가시키는 것으로 나타났다.

○ 연구결과
- 우수종균을 사용하여 미생물 대사공학 기법으로 김치발효시스템을 조절한 결과 김치발효환경내의 종균 점유율(80% 이상)이 탁월하였으며, 김치 상미기간을 약 4개월간 유지함으로서 김치품질의 균일화 및 보존성을 향상시킬 수 있었고 종균에 의한 김치발효 맛을 다양화할 수 있었다.
- Bifidobacteria을 이용한 김치 섭취 시 변비개선 및 장내 미생물 균총 개선효과가 있었으며, 우량종균김치와 비피더스종균김치의 안정성실험 결과 무독하였고 항산화작용 및 HDL-콜레스테롤농도비를 증가시키는 것으로 나타났다.
- 우수종균의 고농도 배양을 위한 신규배지의 개발로 300L 발효조에서의 종균배양이 가능(산업적 배지 가격의 25%↓ 및 균체생산량 약 2배 ↑)하였으며 안정화 종균제품의 농축 후 생균수 6×10¹¹ CFU/g이었으며 액체농축상태에서 5주간 90% 생존율 유지하였다.

Abstract ▼

○ Development of fermentation system for high-tech Kimchi by using Kimchi-starter
Although extensive scientific studies on Kimchi have been carried out, a systematic investigation of Kimchi has been difficult because of the complexity of the preparation methods, varieties of ingredients, and natu

○ Development of fermentation system for high-tech Kimchi by using Kimchi-starter
Although extensive scientific studies on Kimchi have been carried out, a systematic investigation of Kimchi has been difficult because of the complexity of the preparation methods, varieties of ingredients, and nature of fermentation. The fermentation of Kimchi is carried out by various microorganisms, especially the lactic acid bacteria that are present natually in the ingredients. Kimchi quality should be controlled by microorganisms that are present in Kimchi ingredient and various fermentation conditions. The best quality Kimchi may be obtained from day 5 until day 14. After day 14, it might be classified as overripped Kimchi. Commercial shelf life of Kimchi is considered as day 28. In this study, we tried to expand Kimchi shelf life and to control the Kimchi fermentation by using Kimchi-starter strain which was isolated from Kimchi. We achieved to control the Kimchi fermentation by Kimchi starter usage(＜80∼90% dominant m/o in Kimchi) and to expend Kimchi shelf life up to 4 months by using microbial metabolic engineering and regulation technique. Such starter using technique leads to diminish undesirable microorganisms which can be occurred during Kimchi fermentation and to control the Kimchi fermentation artificially.
The results have advantage for good flavored-Kimchi(high quality) and long-term shelf life of Kimchi.
○ The physiological efficacy of traditional by microbial-engineering
In the first experiments, to investigate the toxicological effects of kimchi lactic acid bacteria, we performed the oral subacute toxicity test, and the acute toxicity test of peritoneal injection and per oral using mice. In the subacute oral toxicity test, kimchi lactic acid bacteria was administerd into mice at a dosage of 5 g/kg, and then mice were brought up for 4 weeks. No clinical signs and pathological changes were observed in mice treated kimchi lactic acid bacteria throughout the experimental period. In addition, there were also no significant changes in general conditions, body weight gain, serum biochemical analyses and any gross or histopathological lesions. Peritoneal and oral acute toxicity tests in mice were also conducted to evaluate the toxicity of kimchi lactic acid bacteria. The LD50 of kimchi lactic acid bacteria was 5 g/kg in oral toxicity test and 2.5 g/kg in peritoneal toxicity test, respectively.
Therefore, the major dominant or main lactic acid bacteria strains isolated from kimchi were evaluated for safety reagent on toxicity and side effect to the mouse.
In the second experiments, to investigate the protective effects of the major dominant or main kimchi lactic acid bacteria on ethanol-induced liver damage in rat. The growth rate and feed efficiency ratio were decreased by ethanol, but increased by administering kimchi lactic acid bacteria. The serum ALT and AST activities that were elevated by ethanol were significantly inhibited by the kimchi lactic acid bacteria administration. It was also observed that GSH-Px activity and glutathione content in liver increased by ethanol were also markedly decreased in the kimchi lactic acid bacteria administered group as compared to the control group. Among the kimchi lactic acid bacteria groups, the main kimchi lactic acid bacteria group showed greater effects on inhibiting free radicals and increasing anti-oxidative enzyme activities than the major dominant kimchi lactic acid bacteria group or commercial kimchi group.
In conclusion, decrease in free radicals and increase in anti-oxidative enzyme activities of kimchi lactic acid bacteria groups suggesting that the kimchi lactic acid bacteria might have important role on retarding aging and could be developed as a new anti-oxidant agents.
In the third experiments, cholesterol lowering effects of the rat administered with the major dominant or main lactic acid bacteria isolated from kimchi were studied. Male Sprague-Dawley rats were administered 1% cholesterol and 0.25% sodium cholate to induce hypercholesterolemia. It was found out that significant decrease in body weight gain, feed efficiency ratio, serum triglyceride level, serum total cholesterol level, LDL-cholesterol level and atherogenic index was observed in kimchi lactic acid bacteria groups as compared to control group fed only high cholesterol diet. Decreased HDL-cholesterol level by high cholesterol diet was re-increased by kimchi lactic acid bacteria administered groups. Among the kimchi lactic acid bacteria groups, the main kimchi lactic acid bacteria group also showed greater effects on lowering cholesterol level and atherogenic index than the major dominant kimchi lactic acid bacteria group or commercial kimchi group. Taken together, it is suggested that the kimchi lactic acid bacteria exerts antiatherosclerotic effect by reducing serum cholesterol level.
○ Healthy aspects of Bifidobacterium animalis DY-64 Kimchi
To identify healthy aspects of Bifidobacterium animalis DY-64 we prepared Kimchi containing B. animalis DY-64 and provided to 10 subjects with constipation symptom for 2 weeks. We investigated the improvement of constipation symptoms, change of intestinal microflora, enzyme activity in feces, and immune activities of serum during entire experimental period.
Constipation indexes including bowel movement frequency, straining, stool consistency, hard stool, sense of complete evacuation were significantly(p<0.05) improved during the Kimchi administration period. Bifidobacteria and lactobacilli in feces significantly(p<0.05) increased while Bacteroides spp., Clostridium spp., Escherichia coli and Staphylococcus spp. significantly(p<0.05) decreased during the Kimchi administration period. Moreover, enzymatic activities of β-glucuronidase or β-glucosidase in feces significantly(p<0.05) decreased while the content of IL-2 and TNF-α significantly(p<0.05) in serum increased. From these results, We found that B. animalis DY-64 can be used to prepare functional foods because Kimchi containing Bifidobacterium animalis DY-64 showed the improvement of constipation, intestinal microflora, enzyme activity in feces, and immune activity in serum.
○ Optimization and development of fermentation and storage conditions for industrial application.
To settle down the starter Kimchi making process, starter strain should be supplied in industrial scale. Because generally LAB need a complete nutritional supply, cost for fermentation of starter strain result in increasing original Kimchi making cost. To overcome these problems in starter Kimchi making process, efficient fermentation system, newly reconstructed low cost medium, and storage condition of starter strain should be developed. So, our research purpose is to find out the solution of those problems.
In first research year, optimum growth, agitation methods, pH controlling system and pH controller were determined. All fermentation data were obtained from 5L-jar fermentation not flask culture. When these fermentation conditions were applied in 300L-scale fermentation, almost the same fermentation results as cell growth time, pH controlling methods, and final cell concentration, were obtained.
Also new medium compositions were determined only for Kimchi starter. two types of media were developed and called as reconstructed medium 1 and reconstructed medium 2. Cost of reconstructed medium was 25% - 75% lower than commercial media which was used for LAB production in OEM company.
Final cell concentration in reconstructed medium was more than 5 x 10⁹ cfu/ml. Generally when Kimchi starter was grown in MRS medium, Final cell concentration was less than 3 x 10⁹ cfu/ml. These results means that reconstructed medium could replace the commercial LAB production medium and be used for LAB production exclusively.
Finally, storage condition was set-up. Under these conditions, cell (〉10¹¹ cfu/ml) could survive in the ratio of more than 90% in 28 days. When these stored-concentrated cell was applied in Kimchi making process, there was no any problem caused by stored cell.

목차 Contents

• 표지 ... 1
• 제출문 ... 2
• 요약문 ... 3
• SUMMARY ... 19
• CONTENTS ... 25
• 목차 ... 29
• 제1장 연구개발 과제의 개요 ... 33
• 제1절 연구개발의 필요성 ... 33
• 1) 기술적 측면 ... 35
• 2) 경제.산업적 측면 ... 37
• 3) 사회.문화적 측면 ... 39
• 제2절 연구개발의 목표 및 내용 ... 41
• 제2장 국내.외 기술개발 현황 ... 45
• 가. 국내.외 관련기술의 현황 ... 45
• 나. 국내.외 관련기술의 현황 및 문제점 ... 51
• 제3장 연구개발수행 내용 및 결과 ... 52
• 제1절 첨단미생물공학에 의한 전통김치의 과학화 ... 52
• 1. 연구수행방법 ... 52
• 가. 유산균분리 및 동정 ... 52
• 나. 분리종균의 특성 ... 53
• 다. 박테리오신 특성조사 ... 54
• 라. 분리종균의 발효특성 ... 55
• 마. 우량 신균주를 이용한 김치 발효조절 시스템의 구축 ... 55
• 2. 연구내용 및 결과 ... 59
• 가. 김치유산균의 분리 및 동정 ... 59
• 나. 분리종균의 특성 ... 67
• 다. 분리균주의 발효특성 ... 74
• 라. 우량 신균주를 이용한 김치의 최적 발효대사 제어시스템 개발 ... 79
• 마. 미생물대사제어시스템에 의한 첨단김치의 장기저장 ... 85
• 바. 종균 GJ3에 의한 첨단김치 개발 ... 92
• 사. GJ7종균김치의 관능조사 ... 94
• 아. 당원에 따른 GJ7종균김치의 발효특성 ... 98
• 자. 속성발효에 의한 종균김치의 발효특성 ... 104
• 제2절 미생물대사공학기법으로 제조된 전통김치의 생리활성효능 연구 ... 111
• 1. 연구수행방법 ... 111
• 가. 우량 김치 종균의 독성실험 ... 111
• 나. 우량 신균주를 이용하여 개발된 김치의 노화억제 효능실험 ... 112
• 다. 우량 신균주를 이용하여 개발된 김치의 고지혈증 억제 효능 ... 115
• 2. 연구내용 및 결과 ... 117
• 가. 우량종균김치의 독성실험 ... 117
• 나. 우량신균주를 이용하여 개발된 김치의 노화억제 효능실험 ... 127
• 다. 우량신균주를 이용하여 개발된 김치의 고지혈증 억제효능 ... 137
• 제3절 Bifidobacteria를 이용한 기능성 김치의 제조 ... 145
• 1. 연구수행방법 ... 145
• 가. 실험 대상자 선정 ... 145
• 나. 미생물 준비 및 김치 제조 ... 147
• 다. 통변에 대한 영향조사 ... 148
• 라. 분변 미생물 균총 조사 ... 148
• 마. B. animalis DY-64 확인용 primer 제작 ... 149
• 바. B. animalis DY-64 확인 ... 150
• 사. 유해 효소 ... 151
• 아. 면역력 측정 ... 151
• 2. 연구내용 및 결과 ... 152
• 가. 대상자의 특성 ... 152
• 나. 변비 호전 효과 ... 152
• 다. 분변 미생물 균총 ... 153
• 라. B. animalis DY-64 확인 ... 154
• 마. 유해 효소 ... 156
• 바. 면역력 측정 ... 158
• 제4절 김치 종균의 대량 생산을 위한 배양조건 확립 및 안정화 기술 개발 ... 159
• 1. 서론 ... 159
• 2. 연구내용 ... 159
• 3. 연구방법 및 결과 ... 162
• 가. 생육 온도 및 배지 조성 그리고 배양 방법이 Leuconostoc citreum GJ7의 성장에 미치는 영향 ... 162
• 나. Leuconostoc citreum GJ7의 성장에 탄소원이 미치는 영향 ... 164
• 다. Defined 배지에서 첨가되는 아미노산의 종류에 따른 배양 특성 ... 165
• 라. 배지 pH가 균 생육에 미치는 영향 ... 167
• 마. 5L jar fermentor에서의 물리적 조건이 Lactobacillus plantarum의 발효에 미치는 영향 ... 168
• 바. Leuconostoc citreum GJ7 발효 방식 결정 ... 172
• 사. Leuconostoc citreum GJ7 발효시 배지 pH의 조절 방식 결정 ... 176
• 아. 대체 당 및 대체 단백질의 탐색 ... 177
• 자. 신규배지의 최적화 및 원가 절감 효과 ... 183
• 차. 균주 안정화 조건 확립 ... 185
• 제4장 목표달성도 및 관련분야의 기여도 ... 190
• 제1절 연도별 연구목표 및 평가 착안점 ... 190
• 제2절 연구개발 목표의 달성도 및 관련분야의 기술 발전에의 기여도 ... 191
• 제5장 연구개발의 활용계획 ... 199
• 1. 미생물을 이용한 대사 제어 시스템 ... 199
• 2. 유용 김치 종균의 분리 및 동정 ... 199
• 3. 신규 생균제제(probiotics)로의 활용 ... 200
• 4. 종균제제 산업으로의 응용 ... 201
• 5. 신규 김치 종균용 배지 개발에 따른 상품화 ... 201
• 제6장 참고문헌 ... 202
• 끝페이지 ... 212