• Journal of Dairy Science and Biotechnology
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• 제22권2호
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• pp.91-97
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• 2004

활성산소의 세포막 파괴 효과로부터 보호작용과 항산화 활성이 강한 균주를 선별하기 위하여 33균주에 대한 세포네 glutathione 함유율과 linoleic acid 산화억제활성을 측정하였다. Lactobacillus casei CU4114 25.15 umol/g으로 가장 높은 함유율을 보이고 있으며Lactobacillus rhamnosus CU4201, Lactobacillus plantarum CU4203이 14.0umol/g으로 통계적인 유의성을 나타내는 수준으로 높은 함유율을 나타내었다. 포자형 성균주중의 glutathione 함유율 측정 결과 Lactobacillus sporogenes CU4109, Sporolactobacillus inulinus CU4110 은 Bacillus coagulans 균주의 GSH 함유율보다 유의성이 인정되는 높은 함유율을 나타내었다. L. acidophilus CU4111, L. casei CU4114, L. brevis CU4206, L. helveticus Cu4231은 Lactobacillus spp. 중 높은 항산화 활성을 나타내었고 Bacillus coagulans의 항산화 활성범위는 6.02${\sim}$51.72%로 나타났으며 Bacillus coagulans 균주의 항산화 활성이 Lactobacillus spp.의 산화억제활성보다 높은 성향을 나타내었다.

• 한국가금학회지
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• 제28권1호
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• pp.27-40
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• 2001

This study was conducted to investigate the effects of feeding various Lactobacillus on performance, nutrients digestibility, intestinal microflora, and fecal noxious gas of broiler chicks. One thousand eighty one dat old male broiler chicks were fed into Lactobacillus crispatus avibrd 1(LCB), Lactobacillus reuteri avibro 2(LRB), Lactobacillus crispatus avihen 1(LCH), and Lactobacillus vaginalis avehen 2(LVH) at the level of $10^{4}$ and 10(sup)7cfu/g diet. There were four replicates with thirty chicks per pen. Diets contained ME 3,100, 3,100kcal/kg, and CP 22.0, 20.0% for starting and finishing period, respectively. Weight gain of checks fed Lactobacillus spp. tended to increase from the first week and was higher from 50 to 100g in Lactobacillus treatments than control. Feed intake and feed conversion were not statistically different of all treatments. Dry Matter(DM) digestibility of Lactobacillus treatments was tended to improve compared to that of control, but was not significantly different. Protein and Ca digestibility were also tended to improve in Lactobacillus treatments relative that of control. Lactobacillus treatments showed improved tendency in crude ash and fat compared to those of control, whereas phosphorus digestibility was not consistency. Nutrients digestibilities of bird fed LCH were superior to those of other treatments. It showed significantly higher in Ca and P digestibility than control(P〈0.05). Total Lactobacillus spp. of birds fed various lactobacillus was significantly higher in ileum for five weeks(P〈0.05), but was not different at cecum. Yeast was thought to be not completely attached to intestinal lumen for one week. However, total number of yeast was significantly increased in cecum and ileum from three weeks old chicks(P〈0.05). The number of anaerobes exhibited to tendency the increase in Lantobacillus treatments from one week old of age at both ileum and cecum. Moisture contents of birds fed Lactobacillus spp. was shown from 27 to 30% at five weeks old, whereas it was 38.2% in control. It decreased approximately 25% in Lactobacillus treatments relative to that of control and showed significance between them(P〈0.05). Fecal $NH_{3}$ gas emission was significantly decreased in Lactobacillus treatments and maintained $\frac{1}{3}$to $\frac{1}{2}$ of control(P〈0.05). LCH and LVH treatments were most effective to decrease fecal $NH_{3}$ gas and especiallt impreved ti significantly at the level of the level of 10(sup)7cfu/g diets covpared to that of $10^{4}$ cfu/g diets and control(P〈0.05). In conclusion, feeding Lactobacillus spp. increase performance and nutrients digestibilities of broiler chicks and improve environments of house. Proper supplemental level of Lactobacillus spp. is considered more than $10^{4}$ cfu/g diet.

• 한국미생물·생명공학회지
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• 제41권2호
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• pp.183-189
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• 2013

유산균은 국내외 연구진들에 의하여 피부장벽을 강화하는 효능 및 미백, 보습효과가 뛰어나다는 연구 결과가 보고된 바 있다[5, 26]. Lactic acid인 Lactobacillus rhamnosus는 보편적으로 많이 사용하는 프로바이오틱스인 Lactobacillus casei보다 낮게 측정되는 세포독성 결과와 높은 tyrosinase 억제활성을 바탕으로 멜라닌 생성을 줄임에 따라 미백활성을 가진다. 또한 Lactobacillus rhamnosus 파쇄물은 melanoma cell의 멜라닌 생성 저해능이 Lactobacillus casei보다 월등히 높아, 높은 미백 향장 활성을 가지는 것을 확인 할 수 있다(Table 2). 이는 곧 천연물질로써 기존에 사용하던 합성미백제보다 피부에 독성을 주지 않고, 부작용 없이 피부에 적합한 향장소재로 판단되며, 현대의 새로운 미백향장소재로서 활용가능성이 매우 높을 것으로 사료된다. 더 나아가 항산화 활성은 멜라닌 세포 형성 억제에 직접적으로 영향을 주며, 주름 및 노화 등의 출발점이 되어, 미백 활성도 증가됨을 확인할 수 있다. 따라서, 기능성 향장소재로써 가치가 높은 Lactobacillus rhamnosus는 합성물질 및 기타 천연물을 대체할 수 있는 항산화 및 미백 기능성 향장소재로 다가갈 수 있으며, 향장소재로써 선택의 폭을 늘릴 수 있을 것으로 사료된다.

• 한국식품영양과학회지
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• 제26권6호
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• pp.1237-1245
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• 1997

Interspecific fusants were made from the cells of two strains of Lactobacillus genus, a streptomycin resistant Lactobacillus sp. JC-7 and a kanamycin resistant L. acidophilus 88. The morphological and physiological properties of the fusants were examined by determining bacteriocin productivity, acid-producing activity, ability of carbohydrates utilization and three important enzyme activities. The fusants produced a bacteriocin against indicator strains and fusant No. 1, 4 exhibited a larger inhibition zone compared to that of L. acidophilus 88. $\beta$-Galactosidase, phospho-$\beta$-galactosidase, lipase activities and resistance to NaCl of Lactobacillus sp. JC-7 were better than those of L. acidophilus 88. Fusant No. 3 and 7 exhibited excellent lipase activities. Protease activity and acid productivity of L. acidophilus 88 were better than those of Lactobacillus sp. JC-7. Proteasse activities of all fusants were higher than those of parental strains, and expecially fusant No. 5 and 7 exhibited excellent proteolysis ability.

• Journal of Microbiology and Biotechnology
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• 제34권4호
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• pp.854-862
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• 2024

Lactobacillus is a commonly used probiotic, and many researchers have focused on its stress response to improve its functionality and survival. However, studies on persister cells, dormant cells that aid bacteria in surviving general stress, have focused on pathogenic bacteria that cause infection, not Lactobacillus. Thus, understanding Lactobacillus persister cells will provide essential clues for understanding how Lactobacillus survives and maintains its function under various environmental conditions. We treated Lactobacillus strains with various antibiotics to determine the conditions required for persister formation using kill curves and transmission electron microscopy. In addition, we observed the resuscitation patterns of persister cells using single-cell analysis. Our results show that Lactobacillus creates a small population of persister cells (0.0001-1% of the bacterial population) in response to beta-lactam antibiotics such as ampicillin and amoxicillin. Moreover, only around 0.5-1% of persister cells are heterogeneously resuscitated by adding fresh media; the characteristics are typical of persister cells. This study provides a method for forming and verifying the persistence of Lactobacillus and demonstrates that antibiotic-induced Lactobacillus persister cells show characteristics of dormancy, sensitivity of antibiotics, same as exponential cells, multi-drug tolerance, and resuscitation, which are characteristics of general persister cells. This study suggests that the mechanisms of formation and resuscitation may vary depending on the characteristics, such as the membrane structure of the bacterial species.

• 한국미생물·생명공학회지
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• 제25권2호
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• pp.121-128
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• 1997

A lactic acid bacterium was isolated from kimchi. The isolated strain was identified as the genus Lactobacillus through its morphological, cultural, and physiological characteristics and named as Lactobacillus sp. JC-7. The optimum conditions for the electrofusion between streptomycin (2.5 mg/ml) resistant mutant of Lactobacillus acidophilus 88 and kanamycin (600 $\mu$g/ml) resistant mutant of Lactobacillus sp. JC-7 were evaluated. The highest number of fusants were obtained at a capacitance value of 120 msec (1670 $\mu$F), a field strength of 100 V/cm, and a pulse controller setting of 72$\Omega$. The optimum pH of electroporation buffer was 7.5 and the concentration of divalent cation was 1 mM Mg$^{2+}. Electrofusants were efficiently obtained by addition 20% polyethylene glycol to elec- troporation buffer. The yield of fusion was better than that of using polyethylene glycol mediated chemical induction.

• Food Science and Biotechnology
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• 제15권1호
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• pp.86-90
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• 2006

Two lactic acid bacteria (LAB) with high ${\gamma}$-aminobutyric acid (GABA)-producing capacity were isolated from naturally aged cheese. Examination of the biochemical features using an API kit indicated that the two strains belonged to Lactobacillus. They were gram positive, rod-type bacteria, and fermented arabinose, melezitose, melibiose and xylose, but did not utilize cellobiose or trehalose. 16S rDNA sequencing analysis confirmed that they were Lactobacillus buchneri and Lactobacillus sp. They were accordingly named as Lactobacillus buchneri OPM-1 and Lactobacillus sp. OPM-2, and could produce GABA from MRS broth supplemented with 10 g/L of monosodium glutamate (MSG) at a productivity of 91.7 and 116.7 mg/L/hr, respectively. Cell extracts of L. buchneri OPM-1 and Lactobacillus sp. OPM-2 showed glutamate decarboxylase (GAD) activity, for which the optimum pH and temperature were 5.5 and $30^{\circ}C$, respectively.

• 한국축산식품학회지
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• 제26권1호
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• pp.127-135
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• 2006

우유와 두유를 2:1로 혼합하고 홍삼 추출물을 첨가하여 발효유를 제조하였고 2종류의 스타터를 사용하여 발효 특성을 시험하였다. 2종류의 스타터를 사용한 모든 처리구에서 배양 15시간 후 pH는 $3.90{\sim}3.94$ 사이로 나타나 산 생성 촉진 효과가 있었고, 산 생성은 홍삼 추출물 첨가량이 증가함에 따라 조금씩 증가되는 것으로 나타났다. 홍삼 추출물 첨가량이 증가할수록 생균수는 증가하여 Lactobacillus acidophilus KCTC 3150를 스타터로 사용한 균에서 1.0% 홍삼 추출물 첨가량은 $6.26{\times}10^8\;cfu/mL$로서 최대 균수를 나타내었으며, 배양 12시간 이후에 대조구에서는 감소하는 반면 홍삼 추출물 첨가구에서는 젖산균수는 계속해서 최대균수를 유지하고 있었다. 유기산 생성은 lactic acid인 경우 Lactobacillus acidophilus KCTC3150에서 1.0% 홍삼 추출물 첨가구에서 332.22 mM로 가장 높았으며 홍삼 추출물 첨가량이 증가됨에 따라 lactic acid의 생성량도 증가되었다. 당 분해율은 두 균주 모두 홍삼 추출물 첨가량이 증가함에 따라 stachylose의 분해율이 증가하였고, Lactobacillus acidophilus KCTC3150 균주의 경우 stachylose의 분해율이 최대 19%인 반면, Lactobacillus salivarius subsp. salivarius CNU27의 경우 stachylose의 최대 분해율은 54%로서 분해율이 월등히 높았다. 점도는 홍삼추출물 첨가량이 1.0% 첨가구에서 Lactobacillus acidophilus KCTC3150, Lactobacillus salivarius subsp. salivarius CNU27 각각 780 cP로 가장 높게 나타났다. 관능검사 결과는 0.2% 홍삼 추출물을 첨가하고 Lactobacillus salivarius subsp. salivarius CNU27를 스타터로 사용한 발효유가 $4.14{\pm}0.64$로 기호도가 가장 좋게 나타났다.

• 한국미생물·생명공학회지
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• 제20권1호
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• pp.6-13
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• 1992

유산균주의 균주개량방법의 일환으로 protoplast fusion 방법을 사용하여 lincomycin에 내성을 나타내는 Lactobacillus casei KCTC 1121과 rifampicin에 내성을 나타내는 Lactobacillus delbruckii JK-414의 protoplast 형성과 재생, 융합에 대한 조건 및 융합주의 생리학적 성질 등을 검토하였다. Lactobacillus case와 Lactobacillus delbrueckii JK-414는 삼투압 안정제로 sucrose가 함유된 protoplast forming buffer에서 5$\mu g$/ml의 mutanolysin 으로 $42^{\circ}C$, 15분간 처리 했을 때 protoplast 형성율이 높게 나타났다.

• 한국미생물·생명공학회지
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• 제36권2호
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• pp.96-100
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• 2008

recA 유전자를 특이적으로 증폭하는 PCR을 이용하여 우리나라 전통 침채류 발효에 관여하는 유산균의 다양성을 검토해 보았다. 김치에서 많이 검출되는 유산균 7종 및 대조군으로 Lactobacillus acidophilus를 검출할 수 있는 특이적 PCR primer pair을 이용하여 전통 침채류 5증(갓김치, 동치미, 배추김치, 오이소박이, 총각김치로부터 추출한 DNA를 template로 PCR을 수행한 결과, 5종의 침채류 모두에서 Lactobacillus plantarum과 Lactobacillus sakei가 검출되었지만, Lactobacillus paraplantarum, Lactobacillus pentosus와 대조군인 Lb. acidophilus는 검출되지 않았다. Lactobacillus brevis와 Leuconostoc citreum은 배추김치에서만 검출되었으며, Leuconostoc mesenteroides의 경우 갓김치, 동치미, 배추김치, 오이소박이에서 검출되었다. 주재료의 종류에 따라서 발효에 관여하는 유산균은 차이가 있는 것으로 추정되며, Lb. plantarum과 Lb. sakei가 우리나라 침채류 발효에 가장 널리 관여하는 것으로 사료된다.