• Asian-Australasian Journal of Animal Sciences
• /
• 제27권10호
• /
• pp.1461-1468
• /
• 2014

This study was aimed to examine the antibacterial and antioxidative properties of seven edible plants from Thailand to develop alternative antibiotics as feed additives. The plants include Citrus aurantifolia Swingle (Lime) fruits and its leaves, Sesbania grandiflora L. (Agati sesbania) leaves, Piper sarmentosum Roxb (Wild betal) leaves, Curcuma domestica Valeton (Turmeric) roots, Morinda citrifolia L. (Beach mulberry) leaves, Cassia siamea britt (Siamea cassia) leaves, and Cocos nucifera L. (Coconut) peels. The plants were extracted by methanol, n-hexane, chloroform, ethyl acetate, butanol and water. Antibacterial activities with minimum inhibitory concentration (MIC) were determined by agar diffusion assay against Escherichia coli, Burkholderia sp., Haemopilus somnus, Haemopilus parasuis, and Clostridium perfringens that were considered pathogenic strains in livestock infection. Methanol extracts of C. aurantifolia Swingle fruits and leaves showed the broadest spectrum of antibacterial activities except for C. perfringens. Butanol extract of S. grandiflora L. leaves showed the strongest activity against Burkholderia sp. with MIC, $135{\mu}g/mL$. P. sarmentosum Roxb leaves showed antibacterial activities against E. coli, Burkholderia sp. and H. parasuis. Ethyl acetate and water extracts from C. domesitca Valeton roots showed MIC of $306{\mu}g/mL$ and $183{\mu}g/mL$, respectively against only C. perfringens. Antioxidative activity was determined by 2-diphenyl-2-picryl hydrazyl photometric assay. The methanol extracts of C. aurantifolia Swingle fruits and P. sarmentosum Roxb leaves showed the highest antioxidant activity among all the extracts with 3.46 mg/mL and 2.70 mg/mL effective concentration 50% ($EC_{50}$) values, respectively. Total contents of phenolics and flavonoids were measured from the plant extracts. Methanol extracts of S. grandiflora L. and chloroform extracts of C. domestica Valeton were found to have the highest amount of total phenolics, 41.7 and $47.8{\mu}g/mL$, respectively. Flavonoid content of methanol extracts in S. grandiflora L. T was $22.5{\mu}g/mL$ and the highest among plant extracts tested. These results indicated that C. aurantifolia Swingle, S. grandiflora L., P. sarmentosum Roxb, and C. domestica Valeton have antibacterial and antioxidant activities and can be used as alternative antibiotics or potential feed additives for the control of animal pathogenic bacteria.

• 한국식품영양과학회지
• /
• 제43권2호
• /
• pp.328-332
• /
• 2014

김치는 살균공정 없이 유통되기 때문에 유통과정에서도 발효가 진행되는 특성을 가지고 있어 김치의 산도가 계속 증가하여 김치의 상품성이 저하되는 문제점을 안고 있다. 본 연구에서는 김치발효과정 중 과도한 산생성에 관여하는 균주선발과 더불어 이들 균주의 성장을 억제할 수 있는 항균활성을 지닌 균주를 김치로부터 선발하고자 하였다. 우선 김치과숙 관련 균주를 선발한 결과 Lb. plantarum 20-10, Lb. plantarum A-1, P. pentosaceus A-2, P. pentosaceus A-5, Lb. plantarum A-6, P. pentosaceus B-11로 동정이 되었다. 이들 균주를 억제할 수 있는 항균활성을 지닌 균주를 적숙기 김치로부터 선발한 결과 Lc. lactis, Lb. brevis 두 균주가 항균활성이 우수한 것으로 나타났다. 이들 균주의 김치 종균으로서의 적용 가능성을 살펴본 결과 모든 균주가 PH 3.5에서의 내산성, 3% NaCl에서의 내염성, $4^{\circ}C$에서의 생육가능성을 나타내었다.

• Interdisciplinary Bio Central
• /
• 제3권3호
• /
• pp.10.1-10.8
• /
• 2011

Introduction: Hash functions are computer algorithms that protect information and secure transactions. In response to the NIST's "International Call for Hash Function", we developed a biological hash function using the computing capabilities of bacteria. We designed a DNA-based XOR logic gate that allows bacterial colonies arranged in a series on an agar plate to perform hash function calculations. Results and Discussion: In order to provide each colony with adequate time to process inputs and perform XOR logic, we designed and successfully demonstrated a system for time-delayed bacterial growth. Our system is based on the diffusion of ${\ss}$-lactamase, resulting in destruction of ampicillin. Our DNA-based XOR logic gate design is based on the op-position of two promoters. Our results showed that $P_{lux}$ and $P_{OmpC}$ functioned as expected individually, but $P_{lux}$ did not behave as expected in the XOR construct. Our data showed that, contrary to literature reports, the $P_{lux}$ promoter is bidirectional. In the absence of the 3OC6 inducer, the LuxR activator can bind to the $P_{lux}$ promoter and induce backwards transcription. Conclusion and Prospects: Our system of time delayed bacterial growth allows for the successive processing of a bacterial hash function, and is expected to have utility in other synthetic biology applications. While testing our DNA-based XOR logic gate, we uncovered a novel function of $P_{lux}$. In the absence of autoinducer 3OC6, LuxR binds to $P_{lux}$ and activates backwards transcription. This result advances basic research and has important implications for the widespread use of the $P_{lux}$ promoter.

• 생명과학회지
• /
• 제18권6호
• /
• pp.776-781
• /
• 2008

천연 항균소재로서의 천연물 연구는 대부분 식품으로 쓰이는 식물이나 약용식물을 대상으로 하여 많은 연구가 진행되어 왔으나 각 지방에 자생하는 식물에 대해서는 아직 연구가 미흡한 실정이다. 본 연구는 명아주과 식물에 속하는 제주도 자생식물인 해홍나물(Suaeda maritima)을 대상으로 하여 부위별로 물 추출물과 메탄올 추출물을 조제하여 식품유해미생물을 12종을 대상으로 하여 항균활성, 최소저해농도 및 생육저해율을 분석하였다. 해홍나물의 부위별 항균활성을 보았을 때 줄기나 열매 추출물보다는 뿌리 추출물에서 강한 항균활성이 나타남을 알 수가 있었다. 또한 물 추출물보다는 메탄올 추출물에서 더 강한 항균활성이 나타나는 것을 확인 할 수가 있어서 해홍나물의 주 항균성 물질이 물 보다는 메탄올 더 잘 녹는 물질로 추정된다. 특히 메탄올 추출물에서 그람 양성균인 B. cereus (61 %), B. subtilis (62%)와 그람 음성균 V. parahaemolyticus (62%), V. alginolyticus (59%), V. cholerae (56%)에서 55% 넘는 저해율을 나타내었다.

• 대한임상검사과학회지
• /
• 제38권1호
• /
• pp.26-33
• /
• 2006

Recently, the rapid increase in extended-spectrum ${\beta}$-lactamase (ESBL) producing clinical isolates has become a serious problem. In this study, the epidemiologic features and molecular characteristics of ESBL among clinical isolates of Escherichia coli and Klebsiella pneumoniae, antibiotic susceptibility testing, genotype of the ESBL and patterns of chromosomal DNA from PFGE (pulsed field gel electrophoresis) were observed. A total of 53 ESBL-producing clinical isolates (30 of E. coli and 23 of Klebsiella pneumoniae) were collected from two university hospitals in the period of June to July in 2002 and 2003 respectively. The antibiotic resistance frequency of those 53 strains was tested by the disk agar diffusion method with the result that all the strains were resistant to cephalothin. To other antibiotics, the resistance rates of E. coli (30 isolates) were in order of ceftazidime (90.0%), cefotaxime and aztreonam (respectively 83.3%). Also, the resistance rates of K. pneumoniae (23 isolates) were in order of aztreonam (78.3%), ceftazidime (73.9%) and cefotaxime (65.3%). Also the sensitivity of ceftazidime-clavulanic acid were 100% in E. coli and 95.7% in K. pneumoniae. And the sensitivity of cefotaxime-clavulanic acid was 96.7% in E. coli and 91.3% in K. pneumoniae. The types of the ESBL genes were determined by using polymerase chain reaction (PCR). Among the 30 isolates of ESBL-producing E. coli, 6 (20.0%) have SHV only, 5 (16.7%) have TEM only and, 18 (60.0%) have both of TEM and SHV. Among the 23 isolates of ESBL-producing K. pneumoniae, 7 (30.4%) have SHV only, 2 (8.7%) have TEM only, and 14 (60.9%) have both of TEM and SHV. These results show that 52 strains, with only one exception, were confirmed as either TEM or SHV. The patterns of Xba I-digested chromosomal DNA of ESBL-producing E. coli and K. pneumoniae isolates were analyzed by PFGE. PFGE patterns of E. coli and K. pneumoniae were multiclonal, but many strains were grouped into a few types. Therefore, it seems that there were clonal outbreaks or possible horizontal spread. In conclusion, the TEM and SHV ${\beta}$-lactamase are most widely spread in E. coli and K. pneumoniae in Korea. As these types are usually carried by plasmids, the spread of these ${\beta}$-lactamase genes could compromise the future usefulness of third generation cephalosporins for the treatment of infections caused by E. coli and K. pneumoniae.

• 한국식품과학회지
• /
• 제45권4호
• /
• pp.495-500
• /
• 2013

약용식물 3종에 대한 항균활성 결과, 보골지와 오미자 분획층에서 계혈등 분획층보다 높게 나타났다. 계혈등과 보골지 n-hexane 분획층에서 그람 음성균보다 그람 양성균에 대한 항균활성이 유의적으로 높게 나타났으며(p<0.05), 항균활성은 농도가 증가함에 따라 증가하였다. 계혈등 n-hexane 분획층의 L. monocytogenes에 대한 MIC는 7.765 (mg/mL), 보골지 n-hexane 분획층의 B. cereus, L. monocytogenes, E. coli 균에 대한 MIC는 2.03 (mg/mL), 오미자 분획층의 (L. monocytogenes), E. coli 균에 대한 MIC는 8.5 (mg/mL)로 나타났으며, 오미자 n-hexane 분획층의 MIC가 모든 균주에서 가장 낮게 나타났다. 약용식물 추출물의 항균활성에 대한 열 안정성 실험결과, L. monocytogens에 대한 계혈등 n-hexane 분획층을 제외하고는 $100^{\circ}C$에서 10분간의 열처리에도 항균 활성의 변화가 없었다. 본 연구 결과 보골지와 오미자 n-hexane 분획층에서 비교적 높은 항균활성을 나타냈다. 이러한, 약용 식물은 다양한 생리활성 및 기능성 성분을 포함하고 있어 천연 항균제의 유용한 자원으로 이용 될 수 있으며, 식품산업 발달에 기여 할 수 있을 것으로 사료된다.

• 한국응용곤충학회지
• /
• 제23권1호
• /
• pp.15-21
• /
• 1984

강낭콩에서 종자전염된 바이러스병을 동정하기 위하여 각지역 농가 및 시장에서 종자를 수집파종하여 종자전염을 조사한 결과 수원, 장수, 진주에서 채집한 종자가 $2.0\~3.5\%$ 이병되어 있었으며 종자전염된 바이러스를 지표식물에 접종한 결과 강낭콩에 상엽에 모자익, Chenopodium quinoa의 접종엽에 대형의 국부병반이 형성되었다. Dip법에 의하여 시료를 제작하여 입자를 관찰한 결과 약 750nm의 계상입자가 관찰되었다. 이병 강낭콩의 조직에서 Cylinder와 Pinwheel형 및 bundle형의 봉입체(Inclusion hody)가 관찰되었다. 복숭아진딧물에 의하여 충매전염 되었으며 즙액전염된 이병주로부터 채집한 종자의 전염율은 $18.2\%$였다. 물리적성질은 내희석성이 $1,000\~5,000$배 였으며 내보존성은 실온에서 $2\~3$일, 내열성은 $55\~60^{\circ}C$였다. 항혈청검정 결과 혼합침강반응에서 양성의 반응을 나타냈으며 SDS처리에 의한 한천내이중확산법에서 BCMV 항혈청과 band를 형성하였으며 AzMV와는 spur가 형성되지 않았으며 CAMV와는 spur를 형성하였다. 이상의 결과로 강낭콩에서 종자전염된 바이러스는 Bean common mosaic virus로 동정되었다.

• Restorative Dentistry and Endodontics
• /
• 제26권2호
• /
• pp.141-152
• /
• 2001

Eliminating the infecting bacteria of the root canal system and preventing reinfection must be the main objectives of all endodontic works. None of commercially available root canal sealers have the properties of desirable tissue compatibility and strong antibacterial activity. The purpose of this study is to develope an ideal root canal sealer using commercially available polyphosphate (polyP), Calgon, which is known to be antibacterial and safe. For the study. resin type AH26, zinc oxide eugenol type Tubli Seal. Ca(OH)$_2$ type Apexit as base sealers for polyP (0~3%) and para formaldehyde containing N2 as a control base were selected. Specimens (3$\times$4mm) of the sealers were prepared in a 37$^{\circ}C$ incubator for 3 and 10 days and their antibacterial activity against streptococci and black pigmented anaerobic rods was observed using an agar diffusion method. The result were as follows: 1. Among 3 day old root canal sealers. N2 as a positive control showed the strongest antibacterial effect. followed by AH26. Tubli Seal and. Apexit which barely showed antibacterial activity against the test bacteria. In contrast. 10 day old AH26 showed a greater antibacterial activity than 10 day old N2. 2. All sealer specimens showed a greater antibacterial activity against black pigmented anaerobic rods than streptococci. Three day old ones appeared to be more antibacterial than 10 day old ones except for Apexit. 3. As compared to N2, 3 day old AH26 demonstrated a similar antibacterial activity against black pig mented anaerobic rods but to a lesser extent to streptococci. Ten day old AH26 showed a greater antibacterial activity against black pigmented anaerobic rods than 10 day old N2. 4. As compared to AH26. Tubli Seal generally revealed a lower antibacterial activity but it showed a greater antibacterial activity aginst S. gordonii Challis. 5. Enhancement of antibacterial activity by polyP was more clearly observed when it was added to Ca(OH)$^{\circ}C$ based root canal sealers. Tubli Seal and N2. 6. The addition of polyP enhanced the antibacterial activity of 3 day old AH26 against S. gordonii G9B (16%) and Challis (29%), and P. gingivalis 2561 (24%) only. Moreover, polyP failed to increase antibacterial activity of 10 day old AH26 against the test strains but P. gingivalis A7A1 28(13%). 7. The addition of polyP increased the antibacterial effect of 3 day old Tubli Seal on several test bacteria including s. mutans GS 5 (50%). s. gordonii G9B (47%) and Challis (122%). and all the test strains of P. gingivalis (13~35%) except for 9 14K 1. The addition of polyP to 10 day old Tubli Seal increased antibacterial activity of the root canal sealer against most test strains. 8. 3 day old Apexit failed to show antibacterial activity. if any very little against S. mutans GS 5 and Pr. intermedia ATCC 49046. However. polyP increased its antibacterial activity by 50 and 69%, respectively. Increase of antibacterial activity of 10 day old Apexit by polyP was more clearly observed than that of 3 day old one.

• Journal of Microbiology
• /
• 제45권5호
• /
• pp.460-465
• /
• 2007

This study was carried out in order to investigate the potential of using plant oils derived from Leptospermum petersonii Bailey and Syzygium aromaticum L. Merr. Et Perry as natural antifungal agents. The antifungal effects of essential oils at concentrations of 0.05, 0.1, 0.15, and 0.2 mg/ml on the dermatophytes Microsporum canis (KCTC 6591), Trichophyton mentagrophytes (KCTC 6077), Trichophyton rubrum (KCCM 60443), Epidermophyton floccosum (KCCM 11667), and Microsporum gypseum were evaluated using the agar diffusion method. The major constituents of the active fraction against the dermatophytes were identified by gas chromatography-mass spectrometry and high-performance liquid chromatography analysis. The antifungal activities of S. aromaticum oil (clove oil) against the dermatophytes tested were highest at a concentration of 0.2mg/ml, with an effectiveness of more than 60%. Hyphal growth was completely inhibited in T. mentagrophytes, T. rubrum, and M. gypseum by treatment with clove oil at a concentration of 0.2 mg/ml. Eugenol was the most effective antifungal constituent of clove oil against the dermatophytes T. mentagrophytes and M. canis. Morphological changes in the hyphae of T. mentagrophytes, such as damage to the cell wall and cell membrane and the expansion of the endoplasmic reticulum, after treatment with 0.11 mg/ml eugenol were observed by transmission electron microscopy (TEM). At a concentration of 0.2 mg/ml, L. petersonii oil (LPO) was more than 90% effective against all of the dermatophytes tested, with the exception of T. rubrum. Geranial was determined to be the most active antifungal constituent of L. petersonii oil. Taken together, the results of this study demonstrate that clove and tea tree oils exhibited significant antifungal activities against the dermatophytes tested in this study.

• 한국자원식물학회지
• /
• 제25권1호
• /
• pp.80-88
• /
• 2012

천연색소를 이용한 천연 색조화장품 개발을 위한 기초자료로 활용하고자, 15종의 천연색소를 사용하여 제조한 화장료 조성물에 대하여 항균활성 및 항산화능을 조사하였다. 실험에 사용한 6종의 균주 중 Bacillus subtilis, Staphylococcus aureus, Listeria monocytogenes, Vibrio parahaemolyticus, Aspergillus flavus에 대해 대부분의 색소혼합조성물에서 항균활성이 나타나는 것으로 확인되었으며, Proteus vulgaris에서는 다른 균주에 비해 항균활성이 상대적으로 낮았다. 색소종류별로는 자색고구마, 여주, 파프리카, 뽕잎, 지치 등의 색소 조성물에서 다른 색소 조성물에서보다 더 높은 항균활성을 보였다. 또한 DPPH 라디컬 소거능은 양파껍질, 파프리카, 적양배추, 뽕잎, 포도과피, 오디, 레드비트 색소 함유 조성물에서 상대적으로 높은 활성을 보였으며, 아질산염 소거능에 있어서는 특히 pH 1.2에서 적양배추, 포도과피, 오디, 백년초를 제외한 대부분의 색소에서 70% 이상의 높은 활성을 나타냈다. 다양한 천연색소를 이용하여 수행한 본 실험을 통해 천연색소의 높은 항균효과와 항산화능을 확인할 수 있었으며, 향후 이러한 기능성을 활용한 안전한 천연 색조화장품 개발에 유용한 자료가 될 것으로 기대한다.