• Applied Biological Chemistry
• /
• 제41권2호
• /
• pp.166-174
• /
• 1998

저장성이 좋지 않은 숙면(熟麵)을 식초, 젖산, 구연산, 사과산과 같은 유기산에 침지하여 총균수와 기계적 물성을 측정하고 관능검사를 하여 유기산의 효과를 알아보았다. 면가닥을 각각의 유기산 수용액에서 30초간 침유(沈遺)시켜 $pH\;4.7{\pm}0.25$로 맞추어 포장 후 $15^{\circ}C$에서 4일간 저장하는 동안 총균수와 혼탁도를 비교 측정했다. 총균수에서는 식초, 젖산, 구연산, 사과산, 대조구 순으로 총균수 억제 효과를 나타내었고 혼탁도에서는 대조구, 젖산, 사과산, 구연산, 식초 순으로 높았다. 또한 $35^{\circ}C$에서 30일간 저장하면서 Rheometer를 이용하여 물성을 측정한 결과 견고성과 부착성은 대조구보다 유기산처리구가 높게 나타났고, 응집성과 탄성은 다소 감소 추세였으나 큰 변화가 없었다. 껌성은 대조구보다 사과산과 구연산 처리구가 다소 높았다. 관능검사에 의한 종합적인 선호도 순서는 사과산>구연산, 젖산>대조구, 식초순으로 1% 수준의 유의적 차이의 결과를 얻었다.

• 한국미생물생명공학회:학술대회논문집
• /
• 한국미생물생명공학회 2002년도 학술발표대회
• /
• pp.98-98
• /
• 2002

• 한국식품영양학회지
• /
• 제30권3호
• /
• pp.395-404
• /
• 2017

Probiotics may be defined as microbial agents that can benefit humans and have been used primarily by mankind in fermented foods. A representative of probiotics is lactic acid bacteria (LAB), which has received attention recently due to its perceived health benefits. We reviewed research papers about Bifidobacerium and Lactobacillus, which are two of the most known of the LAB. Bifidobacerium alleviates diarrhea from various causes by improving intestinal microflora, and it has been reported that it reduces Helicobacter pylori bacteria known as the cause of gastric ulcer and stomach cancer. Bifidobacerium has also reported to be effective on immunization and allergy, reduce blood cholesterol, cancer, lactose intolerance. Lactobacillus alleviates diarrhea but has not fully demonstrated its effectiveness relative to other health issues. Several lactic acid bacteria and yeast are expected to act as probiotics, so, in the future, more research on the health benefits of lactic acid bacteria is needed.

• 한국축산식품학회지
• /
• 제35권4호
• /
• pp.541-550
• /
• 2015

The purpose of this study was to investigate the effect of lactic acid bacteria (LAB) cell wall extract on the proliferation and cytokine production of immune cells to select suitable probiotics for space food. Ten strains of LAB (Lactobacillus bulgaricus, L. paracasei, L. casei, L. acidophilus, L. plantarum, L. delbruekii, Lactococcus lactis, Streptococcus thermophilus, Bifidobacterium breve, and Pedicoccus pentosaceus) were sub-cultured and further cultured for 3 d to reach 7-10 Log colony-forming units (CFU)/mL prior to cell wall extractions. All LAB cell wall extracts failed to inhibit the proliferation of BALB/c mouse splenocytes or mesenteric lymphocytes. Most LAB cell wall extracts except those of L. plantarum and L. delbrueckii induced the proliferation of both immune cells at tested concentrations. In addition, the production of T_H1 cytokine (IFN-γ) rather than that of T_H2 cytokine (IL-4) was enhanced by LAB cell wall extracts. Of ten LAB extracts, four (from L. acidophilus, L. bulgaricus, L. casei, and S. thermophiles) promoted both cell proliferating and T_H1 cytokine production. These results suggested that these LAB could be used as probiotics to maintain immunity and homeostasis for astronauts in extreme space environment and for general people in normal life.

• 한국식품과학회지
• /
• 제33권5호
• /
• pp.545-550
• /
• 2001

Effects of high hydrostatic pressure on pH, titratable acidity, color, hardness and microorganisms of Chinese Cabbage Kimchi were investigated. Kimchi was pressurized at $200{\sim}600$ MPa for 5 min. There were no significant differences in color and hardness between control and pressurized Kimchi (p>0.05). Total aerobes and lactic acid bacteria were effectively inactivated by high hydrostatic pressure above 400 MPa. Changes in pH, titratable acidity, color, hardness and microbial counts for 4 weeks storage of Kimchi were investigated Kimchi was pressurized at 400 MPa for 5 min and stored at $4^{\circ}C$. The pH of control decreased to 3.94 but pressurized Kimchi maintained its initial pH value throughout the storage. The color of control showed significantly low values compared with pressureized Kimchi (p<0.05), but hardness was not significantly changed (p>0.05). Total aerobes and lactic acid bacteria in the control were reduced from the initial value of $10^8{\sim}10^9$ CFU/mL to $10^6$CFU/mL after 4 weeks storage. Whereas microbial counts in pressurized Kimchi was maintained about $10^3{\sim}10^4$ CFU/mL during storage.

• 한국식품영양학회지
• /
• 제9권3호
• /
• pp.289-293
• /
• 1996

Population changes of aerobic bacteria and lactic acid bacteria and changes of pH, acidity, and total sugar content were creased from initial period of fermentation. Lactic acid bacteria Increased during the first one nay rapidly and thereafter they creased slowly thereafter. Acidity increased on the third day of fermentation. Acidity was very low In Kimchi containing both Total sugar content decreased gradually from initial period to late period of fermentation.

• 한국섬유공학회:학술대회논문집
• /
• 한국섬유공학회 1997년도 춘계학술발표회 논문집
• /
• pp.328-332
• /
• 1997

Hot stretching focused on the improvement of properties of poly(L-lactic acid) fiber. Some aliphatic polyesters are biodegradable under microbial attack and the new unique applications are expected. Generally, these materials have a somewhat low melting temperature and low mechanical properties compared with the aromatic polyesters. In this study, melt-spinning of poly(L-lactic acid) was conducted. We investigated effects of the stretching and the molecular orientation of aliphatic polyester fibers on the change of fine-structure. Glass transition temperature, molecular orientation and crystallinity increased according to the increase of stretching ratio.

• 한국미생물·생명공학회지
• /
• 제46권4호
• /
• pp.403-415
• /
• 2018

The aims of this novel work were to determine the microbial strains and exopolysaccharide (EPS) producers in water kefir from Nakhon Ratchasima Province, Thailand. Thirty-three microbial strains were identified using 16S rRNA gene analysis consisting of 18 bacterial strains, as 9 strains of acetic acid bacteria (AAB), 9 strains of lactic acid bacteria (LAB), and 15 yeast strains. All bacteria were able to produce EPS with a diverse appearance on agar media containing different sugars at a concentration of 8%. Culture supernatants from AAB and LAB showed 31-64% 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity with the highest antioxidant activity of 64% from Acetobacter pasteurianus WS3 and WS6. Crude EPS from A. pasteurianus WS3 displayed the highest ferric reducing antioxidant power at 280 mM $FeSO_4/g$ EPS, greatest anti-tyrosinase activity at 20.35%, and highest EPS production of 1,505 mg EPS/L from 8% sucrose. These microbes offer beneficial health implications and their EPSs can be used as food additives and cosmetic ingredients.

• 한국식품영양과학회지
• /
• 제33권7호
• /
• pp.1180-1185
• /
• 2004

본 연구는 sourdough 제빵에 관여하는 우수한 효모와 젖산균을 분리, 선별하고 이들의 최적 배지 조성을 연구하였다. 1차 분리된 젖산균 115균주 중 항균성이 우수하고, 산 생성 및 향이 우수한 균주를 선별하여 동정한 결과 Leuconostoc sp.로 나타났다. 효모는 8개 균주를 1차 선별하였으며, 발효와 향이 우수한 균주를 선별하여 동정한 결과 Saccharomyces sp.로 동정되었다. 당 발효성을 실험한 결과, glucose와 sucrose에서 생육이 우수하였으나, 상업적으로 많이 사용하고 있는 sucrose가 좋을 것으로 판단되었다. 젖산균은 밀가루배지에 1% sucrose첨가만으로 생육이 우수하였으나, 효모인 경우는 증식이 더 필요하였다. 추가적으로 분리된 효모의 생육 실험을 하여 나타난 최적배지조성은 wheat flour 0.5%, peptone 0.5%, sucrose 3%로 나타났으며, 젖산균인 경우는 peptone의 첨가없이 wheat flour 0.5%, sucrose 1%로 나타났다.

• 한국미생물·생명공학회지
• /
• 제40권4호
• /
• pp.424-429
• /
• 2012

The intention of this research was to investigate the solubilization of primary sewage sludge using lactic acid bacteria cultured in a glucose and yeast extract medium. Glucose as the carbon source and yeast extract as the source of nitrogen were chosen as an economic medium with the potential for the mass production of lactic acid bacteria. The optimal concentrations of the medium were 3% (w/v) glucose and 2% (w/v) yeast extract. In this study, in order to improve field applications for the solubilization of sludge at sewage treatment plants, a powdered form of lactic acid bacteria was produced. The optimal inoculum of the powder for the maximum efficiency of solubilization was 1% (w/v). In that condition, the SCOD value increased from 8600 (mg/L) at the beginning of experiment to 10290 (mg/L) at 96 h, with the highest solubilization rate (20.6% DDCOD) and 11.2% (SCOD). Also, the TVFAs of the lactic acid bacteria inoculation group were produced more than that of the control group. In particular, acetic acid was produced 5 times more in the experimental group than in the control group. In this research, the potential of lactic acid bacteria in the pretreatment of primary sewage sludge as a solubilizer, and as an energy source producer for microbial fuel cells was revealed.