• Journal of Microbiology and Biotechnology
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• 제2권3호
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• pp.226-229
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• 1992

An ethanol tolerant mutant was selected by successive transfers of Clostridium thermohydrosulfuricum ATCC 33223 into the media with progressively higher ethanol concentrations. The growth kinetics of the mutant were characterized under various growth conditions. Physiological differences such as enhanced growth, tolerance to various solvents, alteration of the optimum temperature and the ratio of end products during fermentation were noticed in the mutant.

• 한국식품영양과학회지
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• 제45권3호
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• pp.386-395
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• 2016

본 연구는 복분자와 클로렐라 혼합물의 기능성 발효제품을 개발하고자 품질 특성을 최대화할 수 있는 최적 발효조건을 확립하고, 확립된 방법으로 제조한 혼합 발효물의 일반성분, 유리당, 유기산, 항균 활성 등 화학적 특성에 대한 품질 특성을 조사하였다. 먼저 복분자와 클로렐라 젖산발효 혼합물의 최적 발효균주를 확인한 결과 젖산 생성이 Lactobacillus plantarum에서 가장 우수한 것으로 평가되었고, 최적 발효 온도는 $37^{\circ}C$였다. 이와 같은 조건으로 복분자와 클로렐라 젖산발효 혼합물을 제조하여 관능평가를 한 결과 종합적 기호도 측면에서 클로렐라 분말 5% 첨가구가 가장 우수한 것으로 평가되었다. 따라서 시판 복분자 착즙액(Rubus coreanus Miquel juice; RCM)과 복분자와 클로렐라 5% 첨가 젖산발효 혼합물(RCM-C5)을 제조하여 일반성분, 유리당, 유기산, 항균 활성 등 품질 특성을 조사하였다. RCM과 비교하여 RCM-C5는 수분의 경우 4.90%, 건량 기준 총당은 14.15%, 건량 기준 조섬유는 0.32% 감소하였다. 한편 건량 기준으로 조단백질, 조지방, 조회분은 각각 13.75%, 0.18%, 0.73% 증가하였다. 색도는 두 시료 모두 밝고 약간의 황색을 띠는 적색이었지만 RCM-C5가 RCM보다 황색을 더 띠었다. RCM과 비교하여 RCM-C5의 유리당 함량은 0.97%, 유기산 함량은 616.30 mg%, 항균 활성은 그람양성균인 Staphylococcus aureus가 5.83%, 그람음성균인 Escherichia coil와 Salmonella Typhimurium은 각각 2.94%, 4.67% 증가하였다. 이상의 결과로 미루어본바 일반 복분자 시제품보다 복분자와 클로렐라 젖산발효 혼합물의 품질 특성이 향상되는 결과를 나타내어, 이를 실제 제품으로 제조한다면 영양 기능성이 풍부한 기능성 발효식품으로 활용이 가능할 것으로 판단된다.

• KSBB Journal
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• 제9권1호
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• pp.8-15
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• 1994

재조합 효모를 이용한 hirudin 발효생산조건의 최적화 연구를 수행하였다. Hirudin 유전자는 GAL10 promoter와 MFal 분비신호, GAL7 terminator와 결합되어 있다. 재조합 효모의 성장속도와 hirudin 최종 농도를 증가시키기 위하여 최적의 배지조성과 배양조건을 결정하였다. 최적의 배지조성과 배양조건은 yeast extract 40g/$\ell$, casamino acid 5g/$\ell$, 포도당 20g/$\ell$, galactose 30g/$\ell$, DO 50%, 온도 $30^{\circ}C$였다. 이 조건으로 2.5$\ell$ 발효조에서 회분식배양을 수행한 결과 비성장속도는 $0.13hr^{-1}$, 최종 건조균체농도는 30g cell/$\ell$, 최종 hirudin 농도는 64mg/$\ell$로 나타났다.

• 한국식품조리과학회지
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• 제20권6호
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• pp.598-606
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• 2004

The application of Dongchimi liquid to Naengmyon broth to improve its eating quality was scientifically explored by reviewing the quality of the product properties. Primarily, the optimum fermentation conditions for Dongchimi from which the liquid portion was extracted were pursued and the optimum mixing ratio sought on the basis of the product physicochemical properties. The liquid portions, periodically extracted from Dongchimi at intervals of two or five days, during fermentation at $10^{\circ}C$, were added to Naengmyon broth. The treatments were prepared at three levels namely, basic broth only ('A') and with ratios of Dongchimi liquid to basic broth of 3:7 (v/v, 'B') and 5:5 (vfv, 'C'). As a typical phenomenon of kimchi fermentation, a gradual decrease in the pH with increasing total acidity was observed as the fermentation of the Dongchimi progressed. At $10^{\circ}C$, the optimum ripening was obtained from day 8, and continued until day 15, when the pH was maintained at about 3.8 to 4.0. The total vitamin C and reducing sugar contents increased until the 13th-day of fermentation, but then decreased thereafter. The turbidity and solid content of the Dongchimi liquid increased with progression of the fermentation. With respect to the color values, the lightness (L) decreased, with increases in the redness (a), yellowness (b) and total color difference $({\Delta}E)$ during fermentation. Most of these observed phenomena for the Naengmyon broth substituted with $30\%$ (Treatment 'A') and $50\%$ (Treatment 'B') Dongchimi liquid, with different storage periods, confirmed the previous fermentation patterns of Dongchimi. A decrease in the pH with increasing total acidity, as well as gradual increases in the total vitamin C and reducing sugars (glucose and fructose) up to the 13th-day of fermentation were accompanied by subsequent declining patterns. The turbidity and solid content of the mixed broth also increased with increasing Dongchimi liquid fermentation period. With respect to the color of the mixed broth, the lightness was decreased, while the redness, yellowness and total color difference increased with increasing Dongchimi liquid fermentation period. It was also proven that the addition of slightly over-ripened Dongchimi liquid to the Naengmyon broth was more preferable.

• Preventive Nutrition and Food Science
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• 제14권2호
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• pp.156-161
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• 2009

Effects of extrusion conditions (barrel temperature and moisture content) and fermentation time on the antioxidant properties of root hair of tissue cultured raw mountain ginseng (MG) were investigated. The barrel temperature/ moisture combinations were: $110^{\circ}C$/25% (MG1), $140^{\circ}C$/25% (MG2), $110^{\circ}C$/35% (MG3) and $140^{\circ}C$/35% (MG4). Red ginseng (RG) was also investigated. The contents of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and polyphenolic increased after fermentation in RG and even more in MG, while extruded ginseng samples exhibited little change. The increases noted with MG and RG occurred during the first 4 days of fermentation. DPPH radical scavenging activity decreased after extrusion and was significantly higher in MG (20.93%) than RG (1.63%) on the first day of fermentation. DPPH radical scavenging activity in the barrel temperature/moisture combinations were 19.01% (MG1), 14.45% (MG2), 20.37% (MG3) and 15.78% (MG4). The content of polyphenolic compounds in ginseng samples displayed a similar trend. Acidic polysaccharide in RG and MG1${\sim}$MG4 were higher than MG, but decreased during fermentation. Crude saponin in RG and MG1${\sim}$MG4 decreased after 15 days of fermentation, while increasing in MG.

• Journal of Biosystems Engineering
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• 제41권2호
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• pp.85-92
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• 2016

Background: The same plant, Camellia sinensis, is used to produce all types of tea, and the differences among the various types arise from the different processing steps that are used. Based on the degree of fermentation, tea can be classified as black, green, white, or oolong tea. Of these, black tea is the most or fully fermented tea. The oxidized polyphenolic compounds such as theaflavins (TF) and thearubigins (TR) formed during fermentation are responsible for the color, taste, flavor, and aroma of black tea. Results: Research indicates that an optimum ratio of TF and TR (1:10) is required to ensure a quality cup of tea. The concentrations of TF and TR as well as desirable quality characteristics increase as fermentation time increases, reaching optimum levels and then degrading if the fermentation time is prolonged. It is also necessary to control the environment for oxidation. There are no established environment conditions that must be maintained during the fermentation of the ruptured tea leaves. However, in most cases, the process is performed at a temperature of $24-29^{\circ}C$ for 2-4 h or 55-110 min for orthodox tea or crush, tear, and curl (CTC) black tea, respectively, under a high relative humidity of 95-98% with an adequate amount of oxygen. Conclusion: The polyphenolic compounds in black tea such as TF and TR as well as un-oxidized catechins are responsible for the health benefits of tea consumption. Tea is rich in natural antioxidant activities and is reported to have great potential for the management of various types of cancers, oral health problems, heart disease and stroke, and diabetes and to have other health benefits such as the ability to detoxify, improve urine and blood flow, stimulate, and improve the immune system.

• 대한본초학회지
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• 제30권4호
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• pp.101-108
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• 2015

Objectives : Positive effects of Ginseng has great research attentions such as anticancer, anti-diabetic, antiaging, liver, immune function, CNS, etc. In this study, we investigated Hydroponic-cultured Ginseng Folium fermented byBacillus subtilisto establish fermentation conditions for enhancing functionality.Methods : Ginseng Folium were cultivated hydroponic-cultured and were extracted with methanol. We inoculateBacillus subtilisfor fermentation by adding to 0%, 3% and 5% sugar respectively and checked antioxidant activities, total phenolic content and total saponin content in 2 days intervals during 11 days. The antioxidant activities were studied by the 1,1-diphenyl-2-picryl hydrazyl(DPPH) radical, 2, 2'-Azino-bis(3-ethylbenzothiazoline-6 sulfonic acid) diammonium salt(ABTS) radical scavenging assay and Reducing power assay. We analyzed the Total phenol content, crude saponin content and ginsenoside content. Moreever, Hepatoprotective effects by Glutamic oxaloacetic transaminase(GOT) and Glutamic pyruvic transaminase(GPT) in Sprague-Dawley rat.Results : The results of DPPH and ABTS were 66.89% and 96.72%, respectively. The reducing power was resulted in optical density of 0.7312 with 3% sugar after 9 days of fermentation. and the concentration at 200 ㎍/㎖. Total phenol content was 36.92㎎/g with 3% sugar after 9 days of fermentation, in which crude saponin content wasn't changed, and ginsenoside content such as Rg3, Re and Rb was increased. Activities of GOT and GPT concentration were decreased in rat.Conclusions : This study suggests that hydroponic-cultured Ginseng Folium fermented byBacillus subtilisin 9 days showed significant efficacy of hepato-protection as well as antioxidant compared to the others. In addition, it shows not only improved value but also utilized hydroponic-cultured Ginseng Folium by fermentation.

• 한국식품영양학회지
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• 제29권6호
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• pp.962-970
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• 2016

Commercialized production of onion vinegar, which has biological activities formed through alcohol and acetic acid fermentation, requires standardization. The objective of this study was to determine optimal conditions of sugar contents ($11{\sim}15^{\circ}Brix$) and agitation rate (100~300 rpm) of fermenter in the alcohol-acetic fermentation for producing onion vinegar. The alcohol and total acidity contents increased, whereas contents of total sugars decreased during alcohol fermentation. Contents of alcohol of 13 and $15^{\circ}Brix$ reactants were about 8% in 36 hr and total acidities of all samples were below 0.2% in 60 hr. During acetic fermentation, total acidity increased with highest value at 9 days (3.2% in 100 rpm), 10 days (4.1% in 200 rpm) and 8 days (4.3% in 300 rpm), respectively. From these results, sugar contents ($13^{\circ}Brix$) were measured for alcohol fermentation and agitation rate (300 rpm) for fast fermentation method of vinegar. The contents of total phenols, flavonoids and quercetin in onion vinegar were 33.3 mg/100 g, 3.0 mg/100 g and 2.0 mg/100 g, respectively. Onion vinegar showed an antimicrobial activity against Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Salmonella typhimurium, Escherichia coli and Enterobacter aerogenes. Antioxidant effect of onion vinegar was 26.23% in DPPH radical inhibition and 58.58% in superoxide dismutase like activity, respectively. Fibrinolytic activity was 1.51 plasmin unit/mL in onion vinegar. In conclusion, onion vinegar processed by alcohol and acetic fermentation had nutritional values and potential biological activities.

• 한국약용작물학회지
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• 제18권6호
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• pp.429-438
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• 2010

The use of cellulolytic lactic acid bacteria in new method to prepare high nutrition complementary foods was investigated. For the screening of cellulolytic lactic acid bacteria, more than 1,150 bacterial colony were isolated from diluted infant feces samples. A typical strain which appeared the most excellent cellulolytic activities was identified novel acidophilic Enterococcus sp. TO-94 through the results of morphological, biochemical and chemotaxonomic characteristics and 16S rDNA sequencing. The optimal lactic acid fermentation conditions of Omija(Schizandra chinensis Baillon) by Enterococcus sp. TO-94 were as follows: pH and temperature were 3.0 and $37^{\circ}C$, respectively, and fermentation time was 20hrs. The fructose and glucose were major free sugar and the contents were 5.83 and 4.30 mg/g after fermentation, respectively. The contents of lactic acid and acetic acid were 9.84 mg/g and 2.08 mg/g after fermentation, respectively. The vitamin $B_1$, $B_2$, niacin, folic acid and C were major vitamin in the fermented broth, the contents were 1.5~3 times higher than those of initial fermentation time. Also, the contents of polyphenol and anthocyanine were 3.8 and 1.2 times higher than those of initial fermentation time.

• 한국식품조리과학회지
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• 제21권2호
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• pp.243-249
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• 2005

제주산 감귤과즙을 이용하여 감귤식초를 제조할 목적으로 식초산 발효균 CV1과 CV2를 분리하고 식초산 생성능력을 산업적으로 이용되고 있는 균주와 비교 검정하고 165 rDNA 염기서열을 분석하고 동정하였다. 분리균은 8일간의 발효에 의하여 산도 $5.5\%$ 이상의 식초산을 생성하였으며, 감귤식초 발효에는 사과식초나 감식초 발효에 이용되고 있는 균주 보다 더욱 적합한 것으로 판정되었다. 분리한 균주는 Gluconacetobacter hanenii(CV2) 및 G. hanenii의 변이주(CV1)로 동정되었다.