• 한국식품영양과학회지
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• 제23권2호
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• pp.293-297
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• 1994

The effect of organic acids on growth and heat resistance of Listeria monocytogenes Scott A were investigated. The growth of L. monocytogenes was inhibited in Tryptic Soy Broth(TSB) with 0.1 or 0.2% of acetic , tartic , propionic , citric and lactic acid at 35$^{\circ}C$, respectively. The growth of l. Monocytogenes did not occur in TSB with 0.2% of acetic acid or propionic acid during 48h of incubation. The heat resistance of L.monocytogenes was affected by kind of organic acid, ph and heating substrate. L.monocytogenes showed more heat resistant in TSB with various organic acids than in 0.1M sodium phosphate with the same organic acids. Heat resistance decreased as pH of heating substrate decreased . Surface-adherent microcolony was more heat resistant than planktonic cell of L. monocytogenes. Propionic and lactic acids more affected on heat resistance of L.monocytogenes than acetic , tartaric and citric acids.

• 한국미생물·생명공학회지
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• 제21권2호
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• pp.176-180
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• 1993

Survival and heat resistance of Listeria monocytogenes Scott A in various nutritional environments and cell type on stainless steel were determined. Viable cell of L. monocytogenes Scott A was most rapidly decreased in phosphate buffer among various media such as NSM (30 g TSB/1 l D.W.), LNM (2 g TSB/1 l D.W.) and phosphate buffer (pH=7) during incubation at 21 and 35C but survived for 15 days at 21C. Vegetative and starved L. monocytogenes Scott A were survived after heat treatment for 5 min at 65C while not detected at 72C.

• Journal of Microbiology and Biotechnology
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• 제2권2호
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• pp.73-77
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• 1992

The effect of a nisin-producing Lactococcus lactis spp. lactis (L. lactis) on the growth and attachment of Listeria monocytogenes Scott A and Brie 1 on stainless steel and their growth in Brain Heart Infusion broth was determined. Viable cells of Listeria decreased rapidly after 9~12 hr of incubation at $21^{\circ}C$ and after 6~9 hr of incubation at $32^{\circ}C$ in the presence of L. lactis. The number of L. monocytogenes Scott A attached to stainless steel in pure culture was $2.5{\times}10^3/\textrm{cm}^2{\;}at{\;}21^{\circ}C{\;}and{\;}2.3{\times}10^3/\textrm{cm}^2{\;}at{\;}32^{\circ}C$ after 48 hr of incubation, but was only $10/\textrm{cm}^2{\;}at{\;}21^{\circ}C{\;}and{\;}1.1{\times}10/\textrm{cm}^2{\;}at{\;}32^{\circ}C$ in the presence of L. lactis. Results from L. monocytogenes strain Brie 1 were similar to those from strain Scott A. The population of L. monocytogenes Scott A which attached to stainless steel with previously adherent L. lactis was $1.8{\times}10^2/\textrm{cm}^2{\;}at{\;}21^{\circ}C{\;}and{\;}8.2{\times}10^2/\textrm{cm}^2{\;}at{\;}32^{\circ}C$, whereas the population attached to sterile stainless steel was $1.2{\times}10^3/\textrm{cm}^2{\;}at{\;}21^{\circ}C{\;}and{\;}2.1{\times}10^2/\textrm{cm}^2{\;}at{\;}32^{\circ}C$. For L. monocytogenes Brie 1, the attached population of the control was $1.6{\times}10^4/\textrm{cm}^2{\;}at{\;}21^{\circ}C{\;}and{\;}3.2{\times}10^2/\textrm{cm}^2{\;}at{\;}32^{\circ}C$, and on stainless steel with adherent L. lactis, it was $1.1{\times}10/\textrm{cm}^2{\;}at{\;}21^{\circ}C{\;}and{\;}6.9{\times}10/\textrm{cm}^2{\;}at{\;}32^{\circ}C$. Surface adherent L. lactis was less inhibitory to attachment of L. monocytogenes on stainless steel than a liquid culture inoculum. Listeria attached to stainless steel survived dry storage for 20 days both in the presence and absence of adherent lactococci.

• 한국미생물·생명공학회지
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• 제25권5호
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• pp.442-447
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• 1997

To development food preservative, antimicrobial activities of Schizandra chinensis (SC) against Listeria monocytogenes Scott A, L. monocytogenes Brie I and L. monocytogenes ATCC 19111 were investigated. The growth of L. monocytogenes Scott A, L. monocytogenes Brie I and L. monocytogenes ATCC 19111 was inhibited apparently in Tryptic Soy Broth (TSB) containing 1% SC at 35$\circ$C and it was found that these had antibacterial effects against a broad spectrum of pathogenic bacteria such as S. aureus ATCC 29737, B. subtilis KCTC 1021, E. coli ATCC 11775. The growth of L. monocytogenes was also inhibited about 3 to 5 log$_{10}$ cycle by 0.1% of three fractions of the alcohol extract such as ether, ethyl acetate and butanol. Acidic, weakly acid and neutral fraction of ether fraction showed inhibitory properties against L. monocytogenes.

• 한국미생물·생명공학회지
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• 제21권3호
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• pp.200-206
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• 1993

The effect of pH (7, 5 and 4) and nisin (100 and 200IU/ml) on heat resistance of Listeria monocytogenes Scott A were determined using citrate-phosphate buffer system. Heat resistance of vegetative and starved cell was decreased as pH value was lower at 65 and 72C. Starved L. monocytogenes was more resistant than vegetative cell at both temperature. Heat resistance of vegetative and starved cell was decreased significantly with treatment of nisin. The effect of nisin was increased significantly at low pH(5, 4). Adherent microcolony was more resistant to heat and nisin than planktonic cell. Contamination of L. monocytogenes may be prevent by using nisin in food and food processing environments.

• Applied Biological Chemistry
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• 제42권1호
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• pp.63-67
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• 1999

NaCl의 농도에 따른 Listeria monocytogenes의 증식속도와 세포내 축적되는 삼투보호물질의 농도를 측정하였다. 삼투압스트레스를 받은 L. monocytogenes는 삼투보호물질인 glycine betaine과 glutamate를 세포내에 축적하였는데, NaCl의 첨가수준이 4%까지 증가함에 따라 축적되는 glycine betaine과 glutamate의 양도 증가하여 각각 685, 345 nmol/mg protein이 세포내에 축적되었다. L. monocytogenes를 효과적으로 제어하기 위해서 NaCl과 상엽추출물을 병용하여 항균효과를 시험하였다. NaCl 2%와 상엽추출물 100 ppm을 TSB에 첨가하여 배양했을 경우 무첨가군에 비해 약 10배 정도의 균수가 저해되었으며, NaCl 2%와 상엽추출물 500 ppm의 경우는 약 $10^5$배, NaCl 2%와 상엽추출물 1,000 ppm의 경우는 약 $10^8$배 정도의 균수가 감소되어 상엽추출물과 NaCl을 병용하면 단독 사용시 보다 뚜렷한 증식저해효과를 보여 주었다.

• 한국식품영양과학회지
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• 제31권2호
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• pp.333-337
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• 2002

소나무를 95% 에탄올로 추출하여 얻은 추출물을 40 mg/mL 첨가하였을때 Listeria monocytogenes Scott A, Listeria monocytogenes Brie I. isteria monocytogenes ATCC 19111 3균주의 성장이 억제되었으며 이를 다시 용매별로 순차 분획한 후 3균주에 대한 증식저해효과는 특히 ether 분획 물이 높게 나타났다. 소나무 추출물 40 mg/mL 첨가에 의해 Listeria monocytogenes 3균주 모두 균체의 성장 단계 중 유도기인 4시간째 회수한 균체에서 높은 생균수 감소 현상이 확인되었다. 전자현미경으로 확인한 균체의 형태는 대조구의 균체표면은 매끈하고 손상의 흔적이 없으나 처리구의 균체의 표면은 손상되었거나 형태가 이상을 일으킨 모습을 볼 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제19권7호
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• pp.718-726
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• 2009

The objective of this study was to develop and validate secondary models that can predict growth parameters of L. monocytogenes Scott A as a function of concentrations (0-3%) of a commercial potassium lactate (PL) and sodium diacetate (SDA) mixture, pH (5.5-7.0), and temperature (4-37DC). A total of 120 growth curves were fitted to the Baranyi primary model that directly estimates lag time (LT) and specific growth rate (SGR). The effects of the variables on L. monocytogenes Scott A growth kinetics were modeled by response surface analysis using quadratic and cubic polynomial models of the natural logarithm transformation of both LT and SGR. Model performance was evaluated with dependent data and independent data using the prediction bias ($B_f$) and accuracy factors ($A_f$) as well as the acceptable prediction zone method [percentage of relative errors (%RE)]. Comparison of predicted versus observed values of SGR indicated that the cubic model fits better than the quadratic model, particularly at 4 and $10^{\circ}C$. The $B_f$and $A_f$for independent SGR were 1.00 and 1.08 for the cubic model and 1.08 and 1.16 for the quadratic model, respectively. For cubic and quadratic models, the %REs for the independent SGR data were 92.6 and 85.7, respectively. Both quadratic and cubic polynomial models for SGR and LT provided acceptable predictions of L. monocytogenes Scott A growth in the matrix of conditions described in the present study. Model performance can be more accurately evaluated with $B_f$and $A_f$and % RE together.

• 식품기술
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• 제7권1호
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• pp.58-62
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• 1994

• 한국식품저장유통학회지
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• 제16권6호
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• pp.985-990
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• 2009

오미자 에탄올 추출물 처리에 의한 균체의 지방산과 단백질 분석 및 형태 변화에 미치는 영향을 비교하였다. 오미자 처리에 의한 L. monocytogenes를 전자 현미경으로 관찰한 결과 오미자 추출물을 처리하지 않은 대조구는 smooth한 모양을 나타내었으나, 오미자 추출물을 첨가한 처리구는 전체적인 균체 표면이 불규칙한 모양을 나타내었고, 세포벽과 세포막의 파괴, 균체의 팽윤현상을 나타내었다. 단백질 변화를 살펴본 결과 오미자 처리에 의한 L. monocytogenes의 균체 단백질은 거의 소실되었다. 균체 지방산은 L. monocytogenes Scott A와 L. monocytogenes ATCC 19111의 경우 13-methylpentadecanoic acid(i-15:0), 12-methylpentadecanoic acid(a-15:0)와 15-methylpentadecanoic acid (i-17:0)의 함량은 감소하였으나 Cis-9,12 octadecanoic acid($18:2^{9,12}$)와 cis-9-octadecanoic acid($18:1^9$)의 함량은 증가하였다. L. monocytogenes Brei I는 13-methylpentadecanoic acid(i-15:0)와 12-methylpentadecanoic acid(a-15:0)의 함량은 감소한 반면 Cis-9,12 octadecanoic acid($18:2^{9,12}$)와 cis-9-octadecanoic acid($18:1^9$)의 함량은 증가하였다. 특히, 세 균주 모두 12-methylpentadecanoic acid(a-15:0)의 함량은 뚜렷이 감소한 반면에 Cis-9,12 octadecanoic acid($18:2^{9,12}$)의 함량은 뚜렷이 증가하였다.