• Preventive Nutrition and Food Science
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• 제2권2호
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• pp.109-120
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• 1997

In order to elucidate roles of lactic acid bacteria(LAB) for the antibiosis occurring in th fermenting environment of Kimchi, 2.052 strains of LAB were isolated from Kimchi. Fifty tow strains which showed antagonistic effect against 4 indicator strains were finally selected and investigated. Based upon responses to protease treatment, antibiosis of the 52 strains of LAB were classified into 3 types. Type A antibiosis resulted from action of antibiotic-like substances which were not affected by protease treatment and which had broad action spectra against even natural inhabitants of Kimchi. Type B antibiosis was due to bacteriocin-like substances which were very sensitive to treatment of protease and more effective against foreign bacteria than original inhabitant microflora. Type C antibiosis was owing to proteinaceous compounds which were activated or induced by the presence of protease and then exerted antibacterial activities. Therefore, lactic acid bacteria appeared to contribute to antibiosis of Kimchi by the concerted action of these three different types of antibacterial compounds. As one of model system for type B bacteriocin, the antagonistic compound produced by LAB31-9 as well as th producer strain itself was further charaacterized. Strain LAB31-9 was identified as L. casei. Bacteriocin produced by LAB31-9 was proteinaceous and stable over wide range of pH and to various solvents, but very labile to heat treatment. Its mode of action was bactericidal. Based upon these data, bacteriocin produced by LAB31-9 was named as 'caseicin K319'. Genetic determinant for the bacteriocin production of LAB31-9 was located in the chromosome.

• Journal of Microbiology and Biotechnology
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• 제13권3호
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• pp.429-436
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• 2003

Pediocin K1 is a bacteriocin produced by Pediococcus sp. KCA 1303-10, isolated from traditionally fermented flatfish in Korea. Pediocin K1-dependent antibiosis and pediocin K1-independent antibiosis against Listeria monocyrogenes were investigated by comparing antibiosis potential of the ped＋ wild-type strain of Pediococcus sp. KCA1303-10 with that of the ped- mutant strain in 3 different media at 3 different temperatures. In the synthetic MRS-APT medium, bacteriocin (pediocin K1)-dependent antibiosis (BDA) acted as the major driving force of overall antibiosis at the initial stage before the pH of the media was not sufficiently lowered, while bacteriocin-independent antibiosis (BIA) took over the major role at the late stage of antibiosis by killing otherwise resistant cells in the modium. The role of BDA increased as the temperature of the system decreased. The antibiosis potential of BDA among the overall antibiosis of Pediococcus against Listeria at $37^{\circ}C$ was calculated as 46%, and as 75% at $25^{\circ}C$. In the skim milk medium, antibiosis of Pediococcus against Listeria was weakened more than 4 log cycles compared to that of the synthetic medium; however, BDA worked as the main antibiosis force regardless of the culturing temperature in the skim milk medium. In the bean soup medium, BDA also worked as the major killing mechanism against Listeria, but BIA played as another suppressing mechanism against otherwise pediocin-resistant Listeria population. These results suggest that a large portion of the inhibitory action of the ped+Pediococcus sp. KCA1303-10 was attributable to the bacteriocin produced by the strain and that viable Pediococcus sp. KCA1303-10 was superior to the purified bacteriocin in suppressing the occurrence of the bacteriocin-resistant Listeria monocytogenes in food systems.

• Journal of Microbiology and Biotechnology
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• 제26권4호
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• pp.748-756
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• 2016

In the present study, a lipopeptide (named AXLP14) antagonistic to Xanthomonas oryzae pv. oryzae (Xoo) was obtained from the culture supernatant of Bacillus amyloliquefaciens B014. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis demonstrated that AXLP14 consisted of surfactin homologs. The minimum inhibition concentration and minimum bactericidal concentration of AXLP14 against Xoo were determined to be 1.25 and 2.50 mg/ml, respectively. At a concentration of 0.613 mg/ml, AXLP14 strongly inhibited the formation of Xoo biofilm. AXLP14 also inhibited the motility of Xoo in a concentration-dependent manner. Applying AXLP14 to rice seedlings significantly reduced the incidence and severity of disease caused by Xoo. In Xoo-infected rice seedlings, AXLP14 strongly and continuously up-regulated the expression of both OsNPR1 and OsWRKY45. In addition, AXLP14 effectively inhibited the Xoo-induced up-regulation of the expression of the abscisic acid biosynthesis gene OsNECD3 and the abscisic acid signalingresponsive gene OsLip9, indicating that AXLP14 may protect rice against Xoo-induced disease by enhancing salicylic acid defense and interfering with the abscisic acid response to virulence.

• Applied Biological Chemistry
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• 제48권3호
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• pp.296-300
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• 2005

Among the root colonizing and plant growth promoting bacteria isolated from the bacterial wilt suppressive soil, five strains were detected to produce siderophores by CAS agar assay. The most effective isolate, TS3-7 strain induced significant suppression of bacterial wilt disease in tomato and pepper plants. Seed treatment followed by soil drench application with this strain resulted in over 80% reduction of bacterial wilt disease compared with the control. Significant disease suppression by TS3-7 strain was related to the production of siderophore. Besides iron competition, induction of resistance of the host plant with siderophore was suggested to be another mode of action that suppress bacterial wilt, based on the lack of direct antibiosis against pathogen in vitro. According to Bergey's Manual of Systemic Bacteriology and 16S rDNA sequence data, TS3-7 stain was identified as Pseudomonas sp. TS3-7.

• 한국미생물·생명공학회지
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• 제25권1호
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• pp.30-36
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• 1997

To genetically breed powerful multifunctional antagonistic bacteria, the urease gene of alkalophilic Bacillus pasteurii was transferred into Bacillus subtilis YB-70 which had been selected as a powerful biocontrol agent against root-rotting fungus Fusarium solani. Urease gene was inserted into the HindIII site of pGB215-110 and designated pGU266. The plasmid pGU266 containing urease gene was introduced into the B. subtilis YB-70 by alkali cation transformation system and the urease gene was very stably expressed in the transformant of B. subtilis YB-70(pGU266). The optimal conditions for the transfomation were also evaluated. From the in vitro antibiosis tests against F. solani, the antifungal activity of B. subtilis YB-70 containing urease gene was much efficient than that of the non-transformed strain. Genetic improvement of B. subtilis YB-70 by transfer of urease gene for the efficient control seemed to be responsible for enhanced plant growth and biocontrol efficacy by combining its astibiotic action and ammonia producing ability.

• 사상체질의학회지
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• 제9권2호
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• pp.287-299
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• 1997

대부분의 음식에 첨가되는 마늘은 소음인의 이질설사(痢疾泄瀉)에 사용되기도 한다. 마늘은 온성(溫性)을 가지는 채(菜)로서 고자리파리를 통한 자연생태학적인 방법으로 온열성(溫熱性)이 있음을 증명할 수 있다. 산(蒜)은 원래 재래종인 소산(小蒜)을 지칭하는 말이었지만 대산(大蒜)(마늘)이 수입되면서 소산(小蒜)과 대산(大蒜) 모두를 나타내게 되었고, 재래종인 소산(小蒜)이 재배되지 않는 지금에는 산(蒜)이라면 대산(大蒜)을 지칭하게 되었다. <동의보감(東醫寶鑑)>에서 인용한 산(蒜)에 대한 문장중 약간의 오류가 있음을 비교고찰할 수 있다. 단군신화에 나오는 '산이십매(蒜二十枚)'는 '마늘 20개' 가 아니라 '달래 20뿌리'로 번역되어야 할 것으로 사료되며, 활동성이 많은 호랑이에 비해 곰은 겨울잠을 자므로 어두운 동굴에서 양기(陽氣)가 강한 쑥과 달래를 먹음으로서 동물성과 야수성을 물리칠 수 있었고, 양수(陽數)의 극치인 21일만에 인간으로 승화하였다는 단군신화에 대한 한의학적 해석이 가능할 것이다. 제례때 금하는 음식 중의 하나인 마늘은 성욕(性慾)을 일으키며 정신을 흥분시키는 작용을 알 수 있으며, 열이 많은 소양인이나 태음인이 마늘을 날 것으로 많이 복용하면 부작용이 나는 까닭을 살펴보았다.

• 농약과학회지
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• 제17권4호
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• pp.379-387
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• 2013

지자체에서 배양하여 보급되고 있는 농업미생물 활용을 증진할 목적으로 18개 농업기술센터에서 51종의 미생물을 수집하여 작물생장촉진 및 식물병 방제와 관련한 기능성인 항균활성, 인산가용화, IAA 및 siderophore 생성능력, 질소고정능력, 가수분해활성을 비교 조사하여 최종적으로 항균활성이 우수하고 다양한 농업적 기능을 보이는 Panenibacillus polymyxa CW균주를 선발하였다. P. polymyxa CW균주는 벼 도열병균, 고추 탄저병균, 채소류 시들음병균, Phomopsis sp., 양파 검은곰팡이병균, 잘록병균(Rhizoctonia solani) 및 고추 역병균에 대하여 높은 항균활성을 보였다. 시험 병원균 중 잘록병균을 제외한 모든 병원균에 대하여 P. polymyxa CW균주는 농과원에서 보유하고 있는 P. polymyxa AC-1보다 높은 항균활성을 보였다. P. polymyxa CW균주는 항균활성 외에도 siderophore 생성, IAA 생성 및 질소고정 능력이 우수한 것으로 나타났다. P. polymyxa CW균주의 siderophore 생성능력은 P. polymyxa AC-1과 비슷하였으나 IAA 생성이나 질소고정능력은 P. polymyxa AC-1보다 우수하였다. 그러나 가수분해능력에 있어서는 P. polymyxa CW균주와 P. polymyxa AC-1균주 모두 활성을 보이지 않았다. 고추 흰가루병을 대상으로 P. polymyxa CW균주를 농도별로 처리하고($10^8$, $10^7$. $10^6$ cfu/ml) 처리 후 10일에 병 억제효과를 조사하였을 때, 가장 높은 농도처리에서 병 발생을 68.3%까지 억제하였다. P. polymyxa CW균주의 처리농도가 감소됨에 따라 병 방제효과도 비례해서 감소되었다. 또한 토마토 흰가루병에 대하여 P. polymyxa CW균주 배양액을 $10^6$, $10^7$, $10^8$ 농도로 희석하여 처리하고 7일 후에 병 발생정도를 조사한 결과, 무처리의 병반면적율이 56.3%인데 비하여 0.03, 19.5, 45.7%로 병 발생을 현저히 억제하는 것으로 나타났다. 고추 흰가루병의 경우처럼 토마토 흰가루병에 대한 P. polymyxa CW균주의 방제효과도 처리농도에 비례하는 것으로 나타났다. P. polymyxa CW균주는 고추 및 토마토 흰가루병에 대하여 높은 방제효과를 보였으며, 방제효과가 밀도에 좌우되는 것으로 나타나 시험한 두가지 흰가루병 방제에 대한 작용기작은 항생작용으로 추측되며 효과적인 병 방제를 위해서는 $10^8$ cfu/ml 이상 농도로 처리해야 할 것으로 생각되었다. 이상의 결과를 근거로 P. polymyxa CW균주는 고추 및 토마토 흰가루병 방제를 위한 유망한 방제제로 사용될 수 있을 것으로 사료된다.