• 미생물학회지
• /
• 제37권2호
• /
• pp.151-157
• /
• 2001

위염 및 위궤양, 심이지장궤양, 위암의 주요한 발병 원인균으로 알려져 있는 Helicobacter pylori의 생육을 특이적으로 억제하는 유산균을 선발하기 위해서, 45종의 유산균에 대하여 paper disk법을 이용한 항균 효과, Caco-2세포에 대한 정착능, urease activity법을 이용한 H. pylori 억제능 등을 파악하고, 유산균 배양액과 H. pylori의 동시배양에 따른 요소 분해효소의 활성 변화와 우유 발효능 등을 실험하였다. H. pylori의 생육을 억제하는 물질의 생성 유무를 확인하기 위하여 paper disk법으로 유산균 배양액에 의한 H. pylori의 생육 억제환을 측정한 결과, 28종의 유산균에서 생육 억제환이 형성되었다. 대부분이 유산 생성에 의한 낮은 pH 때문인 것으로 판단되지만, 일부 균종에서는 항균성 물질에 의한 억제환이 형성되었다. 다른 유산균에 비해서 생육 억제환이 가장 큰 Lactobacillus gasseri MK-03 균주가 H. pylori에 대한 항균 활성이 가장 우수한 것으로 나타났다. 항균 활성을 나타낸 28종의 유산균을 대항으로 Caco-2 세포에 대한 정착능을 실험한 결과, 18종의 유산균에서 정착능이 확인되었으며, Bifidobacterium longum MK-26 균주가 가장 우수한 것으로 나타났다. 특히 반응 2시간 전에 미리 Caco-2 세포에 정착시켰을 때, H. pylori의 정착율은 0.105%에서 0.004%로 감소되었다. 한편 요소 분해효소 활성을 저해하여 H. pylori를 억제하는 유산균을 선발하기 위해서 항균활성이 인정되는 28종의 유산균을 대상으로 실험한 결과, 21종의 유산균에서 요소 분해효소 활성의 저해 효과가 나타났으며, 이중에서 Lb. acidophilus MK-07 균주가 가장 우수한 것으로 판명되었다. 따라서 Lb. gasseri MK-03 균주는 항균 활성에서, Lb. acidophilus MK-07 균주는 요소 분해효소의 활성 억제에 의해서, Bif. longum MK-26 균주는 정착능 저해에 있어서 각각 우수한 H. pylori 생육 억제능을 나타냈다. 한편 최종적으로 선발된 3종의 유산균과 대조균주로서 13종의 유산균에 대해서는 우유 배양실험을 실시한 결과, 3종의 선발균주 모두가 발효유 제품에의 응용 적합성을 나타냈다.

• 한국축산식품학회지
• /
• 제35권4호
• /
• pp.473-478
• /
• 2015

The aim of this study was to screen and In vitro characterize the properties of bacteriocin produced by lactic acid bacteria isolated from Vietnamese fermented pork (Nem chua). One hundred and fifty LAB were isolated from ten samples of Nem chua and screened for bacteriocin-producing lactic acid bacteria. Antimicrobial activity of bacteriocin was carried out by spot on lawn method against both gram positive and gram negative bacteria. One isolate, assigned as KL-1, produced bacteriocin and showed inhibitory activity against Lactobacillus sakei, Leuconostoc mesenteroides and Enterococcus faecalis. To characterize the bacteriocin-producing strain, optimum temperature, incubation period for maximum bacteriocin production and identification of bacteriocin-producing strain were determined. It was found that the optimum cultivation temperature of the strain to produce the maximum bacteriocin activity (12,800 AU/mL) was obtained at 30℃. Meanwhile, bacteriocin production at 6,400 AU/mL was found when culturing the strain at 37℃ and 42℃. The isolate KL-1 was identified as L. plantarum. Antimicrobial activity of cell-free supernatant was completely inhibited by proteolytic enzyme of trypsin, alpha-chymotrypsin and proteinase K. Bacteriocin activity was stable at high temperature up to 100℃ for 10 min and at 4℃ storage for 2 d. However, the longer heating at 100℃ and 4℃ storage, its activity was reduced.

• Asian-Australasian Journal of Animal Sciences
• /
• 제20권6호
• /
• pp.920-924
• /
• 2007

Two experiments were carried out on a laboratory scale. The first involved a study of the effect of green tea on characteristics of fermented juice of epiphytic lactic acid bacteria (FJLB). FJLB was treated with 50 g/L of green tea products as follows: new shoot powder (FJLB+N), leaf powder (FJLB+L), commercial powder (FJLB+P), sterilized new shoot powder (FJLB+SN), sterilized leaf powder (FJLB+SL) or sterilized commercial powder (FJLB+SP). FJLB without any additive was also prepared (Untreated FJLB). After incubation, the number of microorganisms in FJLB were studied. Subsequently, these FJLB were applied at 10 ml/kg to chopped rhodesgrass to study their effects on fermentation. Compared with untreated FJLB, the addition of green tea increased (p<0.05) lactic acid bacteria (LAB) and also aerobic bacteria counts in FJLB. At 60 d of ensiling, all the FJLB treated silages were well preserved, pH and butyric acid content were lower (p<0.001) and lactic acid was higher (p<0.001) than that of the control. Lactic acid content was significantly higher (p<0.001) with treated FJLB than with untreated FJLB. FJLB treated with sterilized green tea decreased (p<0.001) the pH and the lactic acid content was higher (p<0.001) than that in the unsterilized green tea silages.

• 대한수의학회지
• /
• 제54권3호
• /
• pp.139-146
• /
• 2014

Jeotgal (salted seafood) has been one of major fermented foods in Korea for long time. Although there are many studies about Jeotgal in various aspects of food, its immunological importance on hosts has not been elucidated yet. In this study, we investigated if several bacteria isolated from Jeotgal may modulate the function of dendritic cells (DCs), powerful antigen-presenting cells equipped with special immunological capabilities. 4 Jeotgal bacteria were selected as representatives and used for experiments. To treat viable DCs, those bacteria were killed at $60^{\circ}C$ for 30 min. The viability of DCs treated with Jeotgal bacteria was verified and two isolates significantly induced high production of interleukin-12, a representative cell-mediated cytokine of DCs. Surface activation and maturation markers (MHC class II, CD40, CD86) of DCs were analyzed by flow cytometer. In addition, the treated DCs showed significantly high lymphocyte stimulatory capability compared to control DCs based on allogeneic mixed lymphocyte reactions. These observations suggest that Jeotgal isolates can function as immunostimulating bacteria in hosts, like Lactobacillus. Taken together, these experimental evidences may broaden the use of Jeotgal isolates in immunological fields in addition to as a fermented food.

• 한국식품영양학회지
• /
• 제35권6호
• /
• pp.399-410
• /
• 2022

To enhance the bioavailability and bioactivities of mixed herbal medicines (RW), they were fermented with lactic-acid bacteria isolated from kimchi into postbiotics (FRW). Then, from the results of the 16s rRNA sequencing analysis, lactic acid bacteria isolated from kimchi were identified to be of two species, namely Lactobacillus sakei and Leuconostoc mesenteroides. The FRW prepared from the RW were extracted using hot water (HW) and 70% EtOH (EtOH) for comparison of their macrophage-stimulating activities. Based on a comparison of the activities of the FRW extracts, nitric oxide (NO) production of HW was significantly higher than that in EtOH. An analysis of the chemical properties of the extracts showed that HW had higher contents of neutral sugar and uronic acid than EtOH as well as contained a large amount of glucose. In addition, crude polysaccharide (CP) was prepared to enhance the macrophage-stimulating activity. The FRW-CP not only secreted immunostimulatory mediators but also increased the expression of immunostimulatory genes (iNOS, TNF-α, MCP-1, and IL-6). The fractionated FRW-CP contained about 90% neutral sugars, and these sugars were mainly composed of glucose, galacturonic acid, and arabinose. Thus, FRW prepared by fermentation of RW with kimchi lactic acid bacteria were found to be immunostimulatory modulators.

• 한국식품저장유통학회지
• /
• 제20권4호
• /
• pp.573-582
• /
• 2013

본 연구에서는 ${\beta}$-glucosidase 활성이 있는 유산균주를 이용하여 발효인삼의 ginsenoside 유용 유도체의 전환 검토 및 품질특성 알아보고자 하였다. ${\beta}$-glucosidase 활성 유산균주를 검색하여 인삼 및 홍삼 발효에 따른 TLC 패턴, ginsenoside 함량 변화, 총 페놀성 화합물 함량, 전자공여능 및 총당 함량을 분석하였다. $37^{\circ}C$에서 65시간 발효 후 Rg2r, Rh2s, Rh2r은 모두 불검출되었으며, 인삼 및 홍삼 추출물 발효에서 발효전과 비교하여 Rg1, Re는 감소한 반면, Rh1, Rg2s, Rd, Rg3r, Rg3s는 발효 후 모두 증가한 것으로 나타났다. 홍삼에서 대표적인 성분으로 알려져 있는 Rg3의 경우 홍삼액 발효전 $104.56{\mu}g/mL$에서 발효 후 균주 종류에 따라 $114.83{\sim}131.68{\mu}g/mL$으로 증가하였다. 7일간 발효 후 홍삼액의 총 페놀성 화합물 및 전자공여능은 일부 균주에서는 발효전과 비교하여 감소하다가 다시 증가하는 경향을 나타내기도 하였으나, 발효가 0~7일차까지 진행됨에 따라 전반적으로 약간 감소되는 경향을 나타내었다. 전자공여능은 인삼 추출물 발효액은 발효 후 균주 종류에 따라 증가하는 경향을 보였으나, 홍삼 추출액은 발효 후 낮아지는 경향을 보였다. 인삼 및 홍삼 추출액을 첨가하여 유산균주별로 발효를 실시한 결과 총당 함량은 발효에 따라 감소하는 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제28권1호
• /
• pp.95-101
• /
• 2015

Fermented Chlorella vulgaris was examined for its effects on growth performance, cecal microflora, tibia bone strength, and meat qualities in commercial Pekin ducks. A total of three hundred, day-old male Pekin ducks were divided into three groups with five replicates (n = 20 ducklings per replicate) and offered diets supplemented with commercial fermented C. vulgaris (CBT$^{(R)}$) at the level of 0, 1,000 or 2,000 mg/kg, respectively for 6 wks. The final body weight was linearly (p = 0.001) increased as the addition of fermented C. vulgaris into diets increased. Similarly, dietary C. vulgaris linearly increased body weight gain (p = 0.001) and feed intake (p = 0.001) especially at the later days of the feeding trial. However, there was no C. vulgaris effect on feed efficiency. Relative weights of liver were significantly lowered by dietary fermented C. vulgaris (linear effect at p = 0.044). Dietary fermented C. vulgaris did not affect total microbes, lactic acid bacteria, and coliforms in cecal contents. Finally, meat quality parameters such as meat color (i.e., yellowness), shear force, pH, or water holding capacity were altered by adding fermented C. vulgaris into the diet. In our knowledge, this is the first report to show that dietary fermented C. vulgaris enhanced meat qualities of duck meats. In conclusion, our study indicates that dietary fermented C. vulgaris exerted benefits on productivity and can be employed as a novel, nutrition-based strategy to produce value-added duck meats.

• Journal of Applied Biological Chemistry
• /
• 제66권
• /
• pp.492-502
• /
• 2023

This study investigated the antioxidant and immune enhancement activities of Artemisia argyi H. fermented by Lactobacillus plantarum. The fermented A. argyi H. ethanol extract increased scavenging activities of 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS⁺), hydroxyl (·OH), and superoxide (O₂^-) radicals. Particularly, the ethanol extract of fermented A. argyi H. exhibited higher ·OH and O₂^- radical scavenging activities, compared with DPPH and ABTS⁺ radical scavenging activities. To evaluate the immune enhancement effects of the fermented A. argyi H., mice were fed a normal diet supplemented the fermented A. argyi H. at concentrations of 1%, 2%, and 5%, respectively. The supplementation of fermented A. argyi H. dose-dependently increased splenocyte proliferation. In addition, mice fed with 5% fermented A. argyi H. showed enhanced proliferation of T-cells and B-cells, along with increased levels of interferon-γ, interleukin-10, and tumor necrosis factor-α, compared to the normal group. Furthermore, mice fed with fermented A. argyi H. exhibited an increase in prominent probiotics such as Akkermansia muciniphila and Lactobacillus in gut microbiota, compared to the normal group. This study suggests that fermented A. argyi H. with Lactobacillus plantarum could be used as a dietary antioxidant and immune enhancement agent.

• 한국미생물·생명공학회지
• /
• 제39권4호
• /
• pp.350-356
• /
• 2011

십전대보탕의 발효 전 후 성분 변화를 분석하기 위해 8종의 유산균을 이용하여 발효한 십전대보탕과 발효하지 않은 십전대보탕을 비교 분석하여 발효 후 증가한 3종의 성분과 감소한 2종의 성분을 규명하여 각 유산 균주에 대하여 5종 성분의 정량 분석을 실시하였다. 증가한 3종의 성분은 각종 크로마토그래픽 기술을 이용하여 분리 정제 후 NMR, MS 등의 분광학적 분석기법을 이용하여 구조를 규명하였으며, cinnamyl alcohol (1), liquiritigenin (3) 및 nodakenetin (5)으로 규명되었다. 발효 후 감소한 성분은 표준품과 HPLC 비교분석(retention time, DAD spectrum)을 통하여 liquiritin (2) 및 nodakenin (4)으로 구조를 규명하였다. 8종의 유산 균주로 발효한 십전대보탕의 성분 변화를 분석한 결과 L. plantarum KFRI 144 발효물이 다른 유산균 발효물에 비하여 cinnamyl alcohol (1), liquiritigenin (3) 및 nodakenetin (5) 성분이 대체적으로 가장 높게 증가하였으며, liquiritin (2) 및 nodakenin (4) 성분이 가장 큰 비율로 감소하여 8종의 유산 균주 중 발효 효과가 가장 우수하였다.

• 한국식품조리과학회지
• /
• 제17권3호
• /
• pp.224-228
• /
• 2001

김치를 첨가한 발효소세지의 숙성기간에 따른 pH 및 미생물학적 변화를 관찰하여 김치첨가가 발효소세지의 미생물학적 특성에 미치는 영향을 검토하였다. 상업용 starter culture 첨가소세지의 pH는 초기에 5.69였으나 점점 감소되어 5.01에 이르렀고, 김치 첨가량이 증가할수록 pH는 감소되어 fresh kimchi 10, 20%와 powder kimchi 2%좌 4% 첨가 소세지는 초기에 pH가 5.4부근이었으나 저장함에 따라 4.87까지 감소하였다. 미생물의 변화는 starter culture 첨가소세지는 초기의 총세균수, 젖산균수 그리고 효모와 곰팡이수가 김치 첨가 소세지보다 $10^{7}$ cfu/g 수준으로 낮았으나 숙성기간 중 급격하게 증가하여 $10^{10}$cfu/g 수준에 이르렀다. 김치첨가소세지는 초기부터 숙성기간 동안 총세균수, 젖산균수 그리고 효모와 곰팡이수가 김치 첨가로 인해 초기에 $10^{9}$cfu/g 수준으로 약간 높았으나 숙성기간 중 완만하게 증가하여 $10^{10}$cfu/g 수준에 이르러 발효하는 동안 미생물학적 안정성을 보였다.