Bacteriological quality of beef carcass and distributions of pathogens in beef processing environments were investigated to improve the hygienic quality of fresh beef. Total bacterial contamination of carcass surface in slaughtering process and cutting board in cut-meat process showed 10^5-10^6CFU/㎠ and l0^5CFU/㎠ in summer, respectively. The viable bacterial count of cotton glove was similar to that of cutting board during and entire period of year. Microbial contamination of carcass surface, cutting board, cotton glove and deboned meat showed the highest in summer and the lowest in winter during the year. Escherichia coli O157, Pseudomonas aeruginosa, Klebsiella. ornithinolytica, Staphylococcus aureus, E. coli, Tatumella. ptyseos, Serratia odorifera, Aeromonas sobria, Enterobacter cloacae and Flavimonas oryzihabitans were isolated from carcass surface during slaughter treatments. S. aureus, Listeria grayi and L. monocytogenes were isolated from cutting board and L. grayi, Erwinia spp. Salmonella spp. and S. aureus were isolated from cotton glove in cut-meat process environments. Citrobacter freundii, L. monocytogenes, and S. aureus were isolated from deboned meat.

This study was conducted to investigate the antimicrobial activity of grapefruit extracts and polylysine mixture against food-borne pathogens. The mixture was showed a potent and quick antibacterial activity for 5 major bacteria causing food poisoning i.e. Escherichia coli, Escherichia coli O-157, Salmonella typhi, Staphylococcus aureus, Vibrio cholerae. The antibacterial effect of the mixture on the ordinary bacteria inhibiting on the surface of lettuce was lasted even 6 hrs after the treatment, however the mixture was non-effective on the color, smell and taste of lettuce. The treatment with 10% mixture solution of the foods such as fish, meat, rice and bread suppressed the growth of the bacteria and kept the foods more freshly than the untreated foods.

변색미(變色米) 발생(發生)에 관여(關與)하는 병원균(病原菌)과 해충을 분류동정(分類同定)한 결과(結果) 해충으로는 허리노린재과(科)에 속하는 Leptocorisa oratorius가 우점종(優占種)이었고 노린재과(科)인 Menida varipennis. Stollia ventralis 및 Nezara viridula 등이 관여(關與)하였으며 병원균(病原菌)으로는 Drechslera oryzae. Curvularia lunata, Trichoniella padwickii, Sarocladium oryzae, Alternaria tenuis 및 Fusarium solani 등이 관여(關與)하였다. 병원균(病原菌)과 해충의 복합발생시(複合發生時)에 변색미발생(變色米發生)이 더 심하였고 병원균(病原菌)만의 발생시(發生時)는 변색미(變色米) 발생(發生)에 주로 영향(影響)을 미쳤으며 노린재류만의 발생시(發生時)는 수량감수(收量減收)에 더 큰 영향(影響)을 주었다. 그리고 노린재류에 의한 벼 유숙기간(乳熟期間)의 흡즙(吸汁)은 병원균침입(病原菌侵入)을 조장(助長)하여 벼의 질적(質的) 변화(變化)와 양적(量的) 감소(滅少)에 크게 영향(影響)하였다.

오이덩굴쪼김병균 Fusarium oxysporum f. sp. cucumerinum의 소형분생포자는 물한천배지상에서 Fe-EDDHA를 처리하였을 때 시간이 경과됨에 따라 발아율이 증가되어 무처리와 유의차를 보이지 않았으나 발아관의 길이는 현저하게 짧았다. Pseudomonas putid의 Siderophore를 처리하였을 때는 포자의 발아율과군사신장이 모두 현저하게 억제되었다. 토양중에 형성된 후막포자가 발아하는데 필요한 영양물질로 Glucose, Peptone을 각각 씩 첨가하였을 때 에 달하는 높은 발아율을 나타냈고, Glucose 와 Asparagine 를 첨가한 처리도 의 발아율을 보였다. 오이의 근권토양에서 후막포자는 발아후 10일된 유묘에서 의 발아율을 보인 반면 2일된 유묘에서는 정도 밖에 안되었으며, 10일 이상 경과된 묘에서도 발아율이 증가되지 않았다. 근권토양에 Fe-EDDHA를 첨가한 처리와 P. putida를 접종한 처리는 후막포자의 발아를 현저히 억제하였으며, 근권부위에 영양물질을 첨가한 처리에서도 같은 경향이었다. 그러나 비근권토양에 영양물질을 첨가하여 후막포자를 발아시켰을 경우 Fe-EDDHA나 P. putida의 발아 억제 효과가 뚜렷하게 인정되지 않았다. 근권토양에서 후막포자 발아 억제효과는 Fe-EDDHA보다 P. putida를 접증한 처리가 더 큰것으로 나타났다.

초 록 본 연구는 우리나라 주요 산림해충중 흰불나방, 오리나무잎벌레 및 솔잎혹파리 방제 대책의 일환으로 미생물 병원체를 조사하고져 실시하였다. 흰불나방에서 분리된 징충물은 핵다각체 Virus와 Bacillus sp. 일종이엇는데 살충효과는 무처리 에 대해 각각 와 로서 핵다각체 Virus의 경우가 우수하였다. 오리나무잎벌레에서는 세균과 진균 각 1종씩 분리되었는데 그중 진균만이 병원성을 보였으며 이는 백강균의 1종인 Beauveria bassiana로 동정되었고 이 균의 살충력은 무처리구 에 비해 의 높은 비율을 나타내었다. 솔잎혹파리에서는 모두 15종의 미생물이 분리동정되었으나 그중 3개의 세균종류와 3개의 진균이 병원성을 나타냈으며 가장 병원성이 강했던 것은 Fusarium sp.였고 그 다음이 Bacillus sp. I과 Spicaria sp.의 순서였다. 1957연부터 1977연에 걸쳐 솔잎혹파리에서 분리된 병원미생물을 흰불나방 및 오리나무잎벌레에 접종한 결과 어느 경우나 병원성을 인정할 수 없었다.

본 연구는 Kresek유발 균주의 균형을 조사하는 동시에 접종방법에 따른 품종과 균주간의 차이를 관찰하고 1977년에 Kresek이 발생된 전국 123개 지역에서 채집분리된 23균주에 대해 균형의 동정 및 중요품종에 대한 균형의 반응을 조사하는 한편 Kresek 이병짚에서 병균의 월동가능성과 전염원으로서의 이병짚의 중요성을 조사하기 위하여 계획되었다. 1. Kresek 발생지 23개 지역에서 채집분리한 병원균의 균군중 15개 균주는 I균군이었으며, 8개 균주는 II균군에 속하였는데, 발병품종 대부분은 밀양 23호였다. 2. 균군과 Kresek 발병은 사용된 I균군(4균주), II균군(5균주), III, IV균군(각 1균주), V균군(2균주)에 대해 모두 발병을 볼 수 있었으나 균주간에는 발병차이가 많았다. 3. 밀양 21, 22, 23호, 진흥(전남풍군)에서는 I, II, V 균군에 전부 발병을 볼 수 있었으나 유신(황옥군)에서는 II균군에서만 발병되었다. 4. 전염원 하나인 이병짚에서는 병원균이 월동할 수 있었으며, 이병짚 생고시용시 Kresek을 유발시킬 수 있었다.

우리나라에서 처음 발생되었던 Kresek에 과한 발생의 균형 및 재현에 관한 시험결과는 다음과 같았다. 흰빛잎마름병균에 의한 Kresek 현상은 주로 남부방인 전라남도 화순, 무안, 강진, 영암, 곡성, 광산, 경상남도 진양군에서 볼 수 있었다. Kresek 발생지의 병원균의 균형은 I, II, IV, V군에 의한 발생을 나타냈다. 3. Kresek이 가장 심하였던 화순군에서는 21균주중 17균주는 IV군, 2균주는 II군, 2균주는 V군이었으며 광산군의 5균주는 IV군dp 속하는 균주였다. 4. 화순군에서는 II, IV, V군이 혼재하고 있음을 볼 수 있었다. 5. Kresek 재현에 관한 시험에서는 접종 5일만에 발병을 볼 수 있었으며 뿌리 절단법에서 발병율이 현저히 높았고, 분무접종, 침접종에서도 발병을 볼 수 있었다. 6. 병원균농도가 높을수록 발병이 많았다.

Ginseng (Pnanx ginseng C. A. Meyer) is famous worldwide, and is very important cash crop and medicinal herb in Korea. It takes four to five years to produce harvestable ginseng roots, and ginseng is attacked by several pathogens during cultivation. We investigated the disease rate caused by ginseng root rot from 6 years old ginseng cultivation fields (Chungnam; 9 fields, Chungbuk; 11 fields, Gangwon 5 fields). The highest disease severity was Dangjin D (2.9) and the lowest one was Gaesan C (0.6). Of the 625 isolations, 340 isolations were classified as Ilyonectria radicicola and Fusarium solani. Finally, genetic diversity of I. radicicola and F. solani was confirmed by sequence analysis. Among the I. radicicola group, I. mors-panacis, which is known as highly virulent pathogen, and I. liriodendri, I. robusta and I. cyclamicicola, which are weakly virulent pathogens, were identified. In the case of F. solani, it is divided into two groups, but it is necessary to conduct diversity research through genetic analysis and pathogenetic studies using various markers. Based on these results, it could be used as a basic data for control of ginseng root rot pathogens.

This study was conducted to evaluate the effect of chemical blend additives (a combination of ferrous sulfate and aluminum chloride) on decreasing pathogens in poultry litter. A total of 240 broiler chickens were assigned to 4 chemical treatments with 4 replicates of 15 chickens per pen. The four chemical blend additives were a control (no treatment), 25 g ferrous sulfate + 75 g aluminum chloride/kg poultry litter, 50 g ferrous sulfate + 100 g aluminum chloride/kg poultry litter and 100 g ferrous sulfate + 150 aluminum chloride/kg poultry litter. During the 6-wk experimental period, there were significant differences in both E.coli and Salmonella enterica for weeks 4 through 6, but not at weeks 1 and 3, respectively. Consequently, using chemical blend additives that serve as methods to control strict environmental regulations reduced pathogens in poultry litter.

This study examined the effects of chemical blends (a combination of alum and aluminum chloride) on pH, N, and pathogens in duck litter during a six-week experiment. In total, 240 Pekin ducks (160 males and 80 females) were individually distributed into 16 pens, in a randomized experimental design consisting of four treatments and four replicate pens per treatment. Our treatments included a control, T1 (75 g alum + 75 g aluminum chloride/kg duck litter), T2 (100 g alum + 100 g aluminum chloride/kg duck litter), and T3 (150 g alum + 150 g aluminum chloride/kg duck litter). There was no difference among treatments in pH and Total N (TN) at weeks 2, 4, and 6 and weeks 1, 4, 5, and 6, respectively. However, there were significant differences in both pH and TN among treatments at weeks 1, 3, and 5 and weeks 2 and 3, respectively. Regarding pathogens, we found small differences in all treatments in Escherichia coli populations from weeks 1 to 5 and in Salmonella enterica populations from weeks 1 to 3. In conclusion, the addition of chemical blends to duck litter increased TN, which resulted in a lower litter pH, but did not significantly affect pathogen populations.

Background : Ginseng root rot caused by soil-borne pathogens, Cylindrocarpon destructans and Fusarium solani, is a major factors of replanting failure in ginseng cultivation. Some of the phenolic compounds detected in the soil of commercially cultivated American ginseng could inhibit the seed germination and seedling growth of American ginseng. Our study is to investigate the causes of replanting failure of ginseng by overhead flooding treatment and soil incorporation of ginseng fine root in soil infected with root rot pathogens. Methods and Results : To make soil occurring continuous cropping injury, 2-year-old ginseng infected with Cylindrocarpon destructans replanted in soil cultivated ginseng for 5 years. Treatment are as follows: 1) control, 2) water of 2ℓ was irrigate infected soil of 20ℓ, 3) ginseng fine root of 20g was mixed with infected soil of 20ℓ. Soil pH was increased, while other inorganic components were significantly reduced by overhead flooding treatment. Soil incorporation of ginseng fine root decreased soil pH, but increased EC, NO3, P2O5 and K, meanwhile, did not affected changes in organic matter, calcium, magnesium, sodium. Irrigation treatment in soil occurring replanted failure promoted distinctly above-ground growth of ginseng, and inhibited the occurrence of root rot because inorganic nutrient like NO3, P2O5 and K were decreased to optimal levels, and the density of soil pathogens could be reduced. Growth of ginseng was not inhibited, while root rot was promoted by soil incorporation of ginseng fine root. Conclusion : Irrigation treatment was effective in promoting the growth of ginseng and inhibited root rot distinctly. Ginseng fine root remaining in the soil after ginseng harvest did not affect the above-ground growth of ginseng, while promoted the occurrence of root rot.

Background: This study aimed to investigate the antioxidat and antimicrobial activities of the methanol extract and its fractions prepared from the roots of Sanguisorba officinalis L. Methods and Results: The antioxidant activities were compared by evaluating the DPPH radical and nitric oxide (NO) scavenging ability. Measurement of DPPH radical scavenging ability showed that the SC50 values of the ethyl acetate fraction was 3.85 ㎍/㎖. The ethyl acetate fraction exhibited the most effective DPPH radical scavenging ability compared with the other samples. As for the NO scavenging ability, at all tested concentrations, the ethyl acetate fraction showed a higher scavenging activity than that of the extract and other fractions. These results are related to the total phenolic compound and flavonoid contents of the ethyl acetate fraction. Antimicrobial activity against foodborne pathogens was investigated using the disc diffusion assay. The ethyl acetate fraction showed the highest antimicrobial activity against gram-positive Staphylococcus aureus and Bacillus cereus. However, the chloroform fraction had a higher antimicrobial activity against gram-negative Vibrio vulnificus than that of the extract and other fractions. Conclusions: The results show that the ethyl acetate fraction had a higher antioxidant as well as antimicrobial activity, than did the other samples. Therefore, the ethyl acetate fraction has potential application in the food industry.

Background : Root diseases caused by Cylindrocarpon destructans and Fusarium solani decrease the yield and quality of ginseng. Cylindrocarpon root rot is a major disease caused by replanting failure in ginseng garden. Methods and Results : Solarization was done in the infested soil of the greenhouse for summer season (from July 24 to Autumn 31, 2014) after putting green manure (Sudan grass) and calcium cyanamide (CC) into the soil. Mycelium and conidia of C. destructans died at 4 0℃ after 15 hours, and 45℃ after 5 h, but it did not die at 35℃ after 15 h. Those of C. destructans died after keeping it for 2 hours daily at 40℃ for 9 days, and 45℃ for 8 days, but did not die at 38℃ for 9 days. Maximum soil temperature was 55.4℃ in 5 cm depth, 48.7℃ in 10 cm, 44.7℃ in 15 cm, 42.5℃ in 20 cm, and 31.9℃ in 30 cm by putting green manure into the soil and solarization. Reduction of sudan grass increased electrical conductivity (EC), organic matter, P2O5, K, and Mg, while decreased pH, NO3-N, and Na. Addition of calcium cyanamide and urea gave a negative effect on the growth of ginseng because EC and NO3-N were increased excessively than the optimal range. Solarization using green manure mixed with CC was the most effective in decreasing soil-borne pathogens of 2-year-old ginseng. But the root disease that occurred between single treatment of sudan grass and the treatment mixed with calcium cyanamide showed not a significant different. Addition of calcium cyanamide showed the decrease of root weight because leaves were dead early by a excessive increase of EC and NO3-N. Conclusion: Soil disinfection using green manure and solarization in greenhouse was effective in inhibiting root rot, however, it did not completely kill the soil-borne pathogens.

Background: Root diseases caused by Cylindrocarpon destructans and Fusarium solani decrease the yield and quality of ginseng. Cylindrocarpon root rot is a major disease caused by replant failure in ginseng fields. Methods and Results: Solarization of infested greenhouse soil was carried out during the summer season after applying green manure (Sudan grass) and Calcium Cyanamide (CC) on the soil. Mycelium and conidia of C. destructans died at 40℃ after 15 h, but they did not die at 35℃ after 15 h. They also died after keeping the soil at 40℃ for 2 h daily for 9 days, and at 45℃ for 8 days, but they did not die at 38℃ for 9 days. Maximum soil temperature was 55.4℃ at 5 ㎝ depth, 48.7℃ at 10 ㎝, 44.7℃ at 15 ㎝, 42.5℃ at 20 ㎝, and 31.9℃ at 30 ㎝ by incorporating green manure into the soil and using solarization. Solarization using green manure mixed with CC was the most effective in decreasing soil-borne pathogens of 2-year-old ginseng. However, the addition of CC decreased the root weight due to the increase in EC and NO3-N. Conclusions: Soil disinfection using green manure and solarization in a greenhouse environment was effective in inhibiting root rot, however, it did not completely kill the soil-borne pathogens.

Background: In this study, we investigated the antibacterial and nitric oxide (NO) production inhibitory activities of 75% ethanol extract of Prunus sargentii branches and its fractions against acne pathogens. Methods and Results: The antibacterial activity against acne causing pathogens was determined using the disc diffusion assay. The ethyl acetate fraction showed higher activities against Propionibacterium acnes, Staphylococcus aureus and Staphylococcus epidermidis than those shown by other fractions. In the DPPH radical and NO scavenging assays, the butanol fraction showed strong DPPH radical and NO scavenging abilities. These activities were related to the total polyphenol and flavonoid contents of butanol fraction. On the other hand, the chloroform and ethyl acetate fractions exhibited the highest NO production inhibitory activity in Lipopolysaccharide (LPS)-stimulated Raw 264.7 cells compared to those exhibited by other fractions. Conclusions: The extract and its ethyl acetate fraction from the branches of P. sargentii exhibited antibacterial activity and could be used as functional materials in antimicrobial related fields. Moreover, the chloroform and ethyl acetate fractions are potential antiinflammatory agents and butanol fraction acts as an effective radical scavenger.

본 연구는 수박 과실썩음병의 원인균인 A. avenae subsp. citrulli에 대해 항균활성을 갖는 친환경 유기농자재를 개발할 목적으로 오배자(S. chinensis)를 대상으로 수행되었다. 오배자를 MeOH로 추출하여 용매분획을 하였고, 용매분획 중에서 가장 강한 활성을 나타낸 hexane fraction을 column chromatography로 분리하여 활성이 강한 분획들을 GC-MS로 분석하였다. GC chromatogram 상의 주요 peak에 해당하는 mass spectrum과 Wiley library를 비교하여 profiling한 결과, 지방산인 myristic acid, palmitic acid와 3-n-pentadecylphenol이 주요 물질로 검출되었다. 이들 검출 화합물의 항균활성을 검정하기 위하여 표준품을 사용하여 bioassay한 결과, myristic acid와 3-n-pentadecylphenol 화합물이 강한 활성을 보였다. 따라서 오배자로부터 분리한 myristic acid와 3-n-pentadecylphenol 화합물이 항균 활성물질인 것을 구명하였다.

Although several adverse effects have been increased in recent years, synthetic agro-chemicals have been widely used to control diseases on paprika. This research was conducted to isolate and to characterize the antagonistic microorganism to control major paprika diseases, gray mold rot, fruit and stem rot, phytophthora blight, sclerotium rot, and wilt disease. Analysis of the fatty acid and analysis of the 16S rDNA gene sequence revealed that YKJ2 isolated in this research belongs to a group of Burkholderia cepacia. Specially, 16S rDNA gene sequence of YKJ2 showed 99% of sequence similarity with B. cepacia. Observation through the optical microscope revealed that YKJ2 was effective on suppression of the spore germination and the hyphal growth of pathogens. YKJ2 treatment on pathogens induced marked morphological changes like hyphal swelling and degradation of cell wall. In the case of phytophthora blight, the zoosporangium formation was restrained. On the basis of the results of this study, we propose that an antagonistic microorganism, B. cepacia, found in this study naming as “B. cepacia strain YKJ2” and has great potential as one of biological control agents against major diseases of paprika.

파프리카에 발생하는 병들을 방제하기 위하여 합성농약이 광범위하게 사용되어왔지만 최근에 수많은 농약사용의 부작용에 대한 관심이 증가 하고 있다. 파프리카 주요병인 잿빛곰팡이병, 줄기 및 과실썩음병, 역병, 균핵병, 시들음병을 방제하기 위한 미생물을 분리하고 특성을 파악하기 위하여 본 연구를 실시하였다. 지방산분석과 16S rDNA 염기배열은 이 연구에서 분리한 YKJ1가 Serratia marcescens 그룹에 속하는 것을 밝혔다. 특히, YKJ1의 16S rDNA 염기배열은 S. marcescens의 염기서열과 99% 상동성을 보였다. 광학현미경을 통해 YKJ1처리에 의해 병원균의 포자 발아 및 균사 생장이 저해됨을 확인 하였다. YKJ1처리는 팽윤균사와 같은 현저한 형태적 변화와 세포벽의 분해를 유발하였다. 역병균의 경우 유주자낭의 형성이 억제되었다. 본 연구에서 동정한 S. marcescens는 S. marcescens-YKJ1으로 부르고자 한다. 포장실험등과 같은 시험이 차후 더 요구되어지나 파프리카의 주요 병관리를 위한 생물적 방제제의 하나로 가치가 있을 것으로 생각된다.