• Title/Summary/Keyword: bacterial-resistant

Search Result 743, Processing Time 0.033 seconds

Rice Plant Growth Promotion and Induced Systemic Resistance Against Rice strip tenuivirus by a Selected PGPR, Bacillus amyloliquefaciens (PGPR균 EXTN-1 처리에 의한 벼의 생육촉진 및 벼줄무늬잎마름병(RSV)에 대한 유도저항성 발현)

  • Park, Jin-Woo;Park, Kyung-Seok;Lee, Key-Woon
    • The Korean Journal of Pesticide Science
    • /
    • v.15 no.4
    • /
    • pp.485-489
    • /
    • 2011
  • In previous reports, the treatment of Bacillus amyloliquefaciens strain EXTN-1 showed a broad diseasecontrolling spectrum to the plant diseases caused by viral, bacterial, and fungal pathogens as well as the promotion of plant growth. In mechanisms of EXTN-1, treatment of EXTN-1 increased oxidative burst in early stage and induced the expression of resistance genes, PR-1a, PDF1.2. Mechanism involved in induced systemic resistance by EXTN-1 was revealed as simultaneous activation of SA and JA or ethylene metabolic pathways. The purpose of this study was to determine whether B. amyloliquefaciens EXTN-1 has a similar effect on rice plant against Rice stripe tenuivirus (RSV) under greenhouse conditions. When rice seeds were soaked in B. amyloliquefaciens strain EXTN-1, rice plants showed significant systemic resistance against RSV as well as promoted growth. In the case of plant growth, in 30-day old plants treated with B. amyloliquefaciens EXTN-1, the heights, weights, and lengths of roots increased by 12.6%, 9.8%, and 16.0%, respectively confirming the effects of PGPR. When the induced systemic resistance to RSV was examined, in 20-day old plants were treated with B. amyloliquefaciens EXTN-1, the heights, weights, and lengths of roots increased by 8.4%, 10.9%, and 4.8%, respectively compared to the control. Induced systemic resistance was more prominent in susceptible cultivars - Chucheong and Ilpum compared to the resistant cultivar, Nakdong.

Screening the extracts of the seeds of Achillea millefolium, Angelica sylvestris and Phleum pratense for antibacterial, antioxidant activities and general toxicity

  • Sarker, Satyajit Dey;Eynon, Elaine;Fok, Katharine;Kumarasamy, Yashodharan;Murphy, Eavan Marie;Nahar, Lutfun;Shaeen, Ehab Mohammed;Shaw, Nichola Mary;Siakalima, Munachonga
    • Advances in Traditional Medicine
    • /
    • v.3 no.3
    • /
    • pp.157-162
    • /
    • 2003
  • Various extracts of higher plants have been used in traditional medicine systems for centuries. While tropical and sub-tropical plants have received considerable attention from the researchers for evaluation of their bioactivity, temeperate plants have always been neglected somewhat. Similarly, seeds of the plants have not been considered seriously compared to other plant parts, e.g. leaves, stems, roots, flowers, etc. as a potential source for biologically active compounds. As part of our on-going evaluation of the extracts of the seeds of temperate plants, especially from Scotland, for biological activity, Achillea millefolium, Angelica sylvestris and Phleum pratense have been chosen for the present study. Both A. millefolium and A. sylvestris are well known for their traditional medicinal uses in Europe and also in the orient, but there is no report on any medicinal properties of P. pratense available to date. Extracts of the seeds of these plants have been assessed for their antioxidant and antibacterial potential and also for general toxicity. Both DCM and MeOH extracts of A. millefolium showed the most significant broad spectrum antibacterial activity among the three plants and inhibited the growth of almost all test strains of bacteria. The DCM extracts of all three species were active against methicillin resistant Staphylococcus aureus (MRSA) and Citrobacter freundii $(MIC=6.25{\times}10^{-1}\;mg/mL)$. While the MeOH extracts of A. millefolium and P. pratense were active against C. freundii, that of P. pratense was also active against MRSA. The MeOH extract of A. sylvestris did not show any antibacterial activity against any of the eight bacterial strains at test concentrations. The MeOH extract of P. pratense showed the most prominent antioxidant activity $(IC_{50}=145\;{\mu}g/ml)$ and there was no antioxidant activity observed with the DCM extract of A. millefolium. The DCM extract of P. pratense was the most toxic $(LC_{50}=20\;{\mu}g/ml)$ among the extracts.

Microbiological Characteristics of Gamma Irradiated and Low-Salted Fermented Squid (감마선 조사된 저염 오징어젓갈 발효의 미생물균총 특성)

  • Kim, Dong-Ho;Kim, Jae-Hun;Yook, Hong-Sun;Ahn, Hyun-Joo;Kim, Jung-Ok;Sohn, Cheon-Bae;Byun, Myung-Woo
    • Korean Journal of Food Science and Technology
    • /
    • v.31 no.6
    • /
    • pp.1619-1627
    • /
    • 1999
  • Microbiological characteristics of gamma irradiated low salt squid Jeot-gal were examined. Following the fermentation periods, total bacterial cell, Lactobacillus spp., Staphylococcus spp., Streptococcus spp., Pseudomonas spp. and yeast cell number were counted on their selective media and some acid forming bacteria and Pseudomonas spp. were identified. As the gamma irradiation dose increased, the microbial density of early fermentation phase was reduced and the growth rate was delayed. The repression effects on microbiological growth by gamma irradiation were to be higher as salt concentration increased. Adequate conditions of salt concentration and gamma irradiation for low-salt squid Jeot-gal preparation were 10% and 10 kGy, respectively. Lactobacillus sp. 2, Micrococcus varians and Streptococcus sp. I were isolated from 5% salt containing squid Jeot-gal, and Micrococcus morrhuae was from 20% only while Lactobacillus plantarum and Lactobacillus brevis were widespread. Lactobacillus brevis, Pediococcus halophilus and Pseudomonas diminuta were sensitive and Lactobacillus plantarum, Micrococcus morrhuae and Pseudomonas sp. 3 were resistant to gamma irradiation. The diversity of microflora decreased as salt concentration decreased and gamma irradiation dose increased.

  • PDF

Enhanced Extraction of Bioactive Compounds from Bee Pollen by Wet-grinding Technology (벌 화분에서 습식 나노화 공정에 의한 유효성분의 추출)

  • Choi, Yun-Sik;Suh, Hwa-Jin;Chung, Il Kyung
    • Journal of Life Science
    • /
    • v.26 no.6
    • /
    • pp.651-656
    • /
    • 2016
  • Bee pollen is produced by honeybees and is considered one of the most balanced and nourishing nutritional supplements available. Historically, bee pollen has been prescribed for its healing properties and consumed for its high-energy supply. Recent research has provided evidence that bee pollen has diverse biological activities, such as anti-oxidant, anti-inflammatory, anti-bacterial, and even anti-cancer effects. However, the outer membrane of the pollen grain, exine, is highly resistant to most acidic solutions, high pressure, and even digestive enzymes, and the resulting low bioavailability limits its nutritional and clinical applications. This study applied a wet-grinding method to destroy the exine effectively, and it then examined the pollen's enhanced biological activity. First, microscopic observations provided strong evidence that wet grinding destroyed the exine time-dependently. In addition, the content of polyphenols, well-known ingredients of bee pollen and used as internal standards for the quality control of commercial pollen preparations, increased up to 11-fold with wet grinding. Further, the anti-oxidant activity demonstrated on the ABTS anti-oxidant assay, as well as the DPPH radical scavenging assay, was also dramatically increased. Together, the results presented here support a new technology by which bee pollen can be used as a resource for medical, nutritional, and cosmetic applications.

Antimicrobial resistance rates changes according to the amount of the antimicrobial agent in clinically important strain isolated from blood cultures (혈액배양에서 분리된 임상적 주요 균주의 항균제사용량에 따른 내성률 변화)

  • Kim, Jae-Jung
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.17 no.5
    • /
    • pp.653-659
    • /
    • 2016
  • The purpose of the study is to investigate the correlation between the amount of antimicrobial agent (Defined Daily Dose, DDD) and antimicrobial resistance rate (%). The treatment of infectious diseases is becoming increasingly difficult, due to the increase in the number of multi-drug resistant bacteria, making it a clinically significant problem. Among the various factors, antimicrobial abuse is a major cause of antimicrobial resistance. The study was conducted on inpatients in a secondary university hospital in the central region utilizing the hospital's computerized statistical data and microbiological program of laboratory medicine from January 2010 to December 2014 pertaining to the dose of antimicrobial drugs for Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli strains isolated from blood culture. We analyzed the antimicrobial resistance rate per dose with the Pearson correlation coefficient. A significant (positive?) correlation was detected between the cefepime dose and the resistance of E. coli (P<0.033; r=0.907), while a significant negative correlation was found between the tobramycin dose and the resistance of E.coli. (P<0.028; r=-0.917). The aminoglycoside resistance of A. baumannii showed a significant negative correlation (P<0.048; r=-0.881), and the aminoglycoside resistance of E. coli showed a significant negative correlation as well (P<0.001; r=-0.992). In conclusion, the amount of antimicrobial agent (Defined Daily Dose, DDD) (is partly related to) the bacterial strain and its antimicrobial resistance rate (%).

Enhancement of Tomato Tolerance to Biotic and Abiotic Stresses by Variovorax sp. PMC12 (Variovorax sp. PMC12 균주에 의한 토마토의 생물학 및 비생물학적 스트레스 저항성 증진)

  • Kim, Hyeon Su;Lee, Shin Ae;Kim, Yiseul;Sang, Mee kyung;Song, Jaekyeong;Chae, Jong-Chan;Weon, Hang-Yeon
    • Research in Plant Disease
    • /
    • v.24 no.3
    • /
    • pp.221-232
    • /
    • 2018
  • Rhizobacteria play important roles in plant growth and health enhancement and render them resistant to not only biotic stresses but also abiotic stresses, such as low/high temperature, drought, and salinity. This study aimed to select plant growth promoting rhizobacteria (PGPR) with the capability to mitigate biotic and abiotic stress effects on tomato plants. We isolated a novel PGPR strain, Variovorax sp. PMC12 from tomato rhizosphere. An in vitro assay indicated that strain PMC12 produced ammonia, indole-3-acetic acid (IAA), siderophore, and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, which are well-known traits of PGPR. The aboveground fresh weight was significantly higher in tomato plants treated with strain PMC12 than in non-treated tomato plants under various abiotic stress conditions including salinity, low temperature, and drought. Furthermore, strain PMC12 also enhanced the resistance to bacterial wilt disease caused by Ralstonia solanacearum. Taken together, these results indicated that strain PMC12 is a promising biocontrol agent and a biostimulant to reduce the susceptibility of plants to both abiotic and biotic stresses.

Evaluation of Hygienic Ability for the Selection of Disease Resistant Honey Bee (Apis mellifera) Lines (질병저항성 꿀벌 계통 선발을 위한 청소능력 특성 평가)

  • Kim, Hye-Kyung;Park, Chang Gyu;Han, Gug-In
    • Journal of Bio-Environment Control
    • /
    • v.30 no.3
    • /
    • pp.206-211
    • /
    • 2021
  • Hygienic behavior of Honey bees, Apis mellifera, was evaluated by uncapping and removing ability of dead broods from the nest. Hygienic behavior is originated from quantitative traits, which are expected to express key roles in colony defense against mite parasites and bacterial and fungal diseases. It is regarded as one of important characteristics of honey bee's resistance to parasites and pathogens. In this study, five inbreed and two hybrid lines of A. mellifera, the former five inbreed lines, which have been reared for over eight years at the National Academy of Agricultural Science in Korea, and the latter two hybrid lines, which have been bred by crossing between the inbreed lines, were investigated on their hygienic behavior by a pin-killed brood assay at 12hrs and 24hrs after treatment. The results indicated that after 12hrs one inbred line was proved to be hygienic (removal rate of dead brood >90%), three inbred and two hybrid lines showed intermediate behavior, and one inbred line belonged to non-hygienic (removal rate of dead brood <70%). However, after 24hrs, only one line was considered to be intermediate as removal rate was below 90%, thus all except this line had shown hygienic behavior.

A Early Maturity, High Grain Quality and Cold Tolerance Rice Cultivar "Sinunbong 1" (벼 조생 고품질 내냉성 품종 "신운봉1호")

  • Kim, Ki Young;Nam, Jeong Kwon;Choung, Jin Il;Ko, Jae Kwon;Kim, Bo Kyeong;Shin, Mun Sik;Ha, Ki Yong;Ko, Jong Cheol;Baek, Man Kee;Kim, Young Doo;Noh, Gwang Il;Kim, Woo Jae;Park, Hyun Su;Kang, Hyun Jung;Kim, Chung Kon
    • Korean Journal of Breeding Science
    • /
    • v.40 no.2
    • /
    • pp.192-195
    • /
    • 2008
  • 'Sinunbong 1' is a japonica rice cultivar developed from the cross between "Sangjubyeo", high yield cultivar and 'Unbong 17', cold tolerance at Honam Agricultural Research Institute (HARI), NICS, RDA, in 2005. This cultivar has a short grain shape and about 111 days growth duration from transplanting to harvesting in Korean climate condition. This cultivar shows high resistant reaction to the blast, but susceptible to bacterial blight and strip virus. This variety has cold tolerance, compared to Odaebyeo. The milled kernels of 'Sinunbong 1' are translucent with non-glutinous endosperm. It has about 19.2% of amylose content and better palatability of cooked rice compared with 'Odaebyeo'. The milled rice yield of 'Sinunbong 1' is about 5.46 MT/ha under the standard fertilizer level of the ordinary transplanting cultivation. 'Sinunbong 1' would be adaptable to the northern plain, mid-mountainous, southern mountainous of Korea.

Effects of Scutellaria scordifolia Fisch. ex Schrank Extracts on Biofilm Formation and the Activities of Klebsiella pneumoniae (Klebsiella pneumoniae균의 바이오 필름 형성과 활성에 대한 병두황진 추출물의 효과)

  • Yook, Keun-Dol;Ha, Nayoung
    • Korean Journal of Clinical Laboratory Science
    • /
    • v.50 no.4
    • /
    • pp.438-443
    • /
    • 2018
  • The emergence of biofilms have generated urgent alarm in clinical and medicine manufacturing fields engaged in the search for novel antimicrobials from ethno-medicinal plants. The National Institutes of Health (NIH) has estimated that 70% of all microbial infections in the world are associated with biofilms. In addition, the emergence of strains resistant to conventional antibiotics has become a serious threat to global public health. Therefore, finding alternative medicines is a major issue in the field of integrative medicine. In this study, four different herb extracts were screened for biofilm formation and the activities of Klebsiella pneumoniae. Of them, Scutellaria scordifolia Fisch. ex Schrank extracts had inhibitory effects on bacterial growth and biofilm formation. The Scutellaia scordifolia Fisch. ex Schrank extracts did not cause any cytotoxicity to L929 cells. The growth of K. pneumoniae was inhibited compared to other comparators in the experimental group containing Scutellaia scordifolia Fisch. ex Schrank. In a group of experiments with plant extracts, a maximum of 60 times the level of living bacteria was confirmed compared to the controls without the addition of the Scutellaia scordifolia Fisch. ex Schrank extracts. In a group of experiments with a significantly lower level of fluorescence extraction, differential interference contrast imaging showed that the number of K. pneumonae was reduced. These results suggest that extracts of this plant be applied as antimicrobial agents against K. pneumoniae, particularly in biofilm forms.

Risk Factors for the Treatment Failure of Antibiotic-Loaded Cement Spacer Insertion in Diabetic Foot Infection (당뇨병성 족부 감염에서 항생제 혼합 시멘트 충전물 사용의 치료 실패 위험 인자 분석)

  • Park, Se-Jin;Song, Seungcheol
    • Journal of Korean Foot and Ankle Society
    • /
    • v.23 no.2
    • /
    • pp.58-66
    • /
    • 2019
  • Purpose: To evaluate the efficacy of antibiotic-loaded cement spacers (ALCSs) for the treatment of diabetic foot infections with osteomyelitis as a salvage procedure and to analyze the risk factors of treatment failure. Materials and Methods: This study reviewed retrospectively 39 cases of diabetic foot infections with osteomyelitis who underwent surgical treatment from 2009 to 2017. The mean age and follow-up period were $62{\pm}13years$ and $19.2{\pm}23.3months$, respectively. Wounds were graded using the Wagner and Strauss classification. X-ray, magnetic resonance imaging (or bone scan) and deep tissue cultures were taken preoperatively to diagnose osteomyelitis. The ankle-brachial index, toe-brachial index (TBI), and current perception threshold were checked. Lower extremity angiography was performed and if necessary, percutaneous transluminal angioplasty was conducted preoperatively. As a surgical treatment, meticulous debridement, bone curettage, and ALCS placement were employed in all cases. Between six and eight weeks after surgery, ALCS removal and autogenous iliac bone graft were performed. The treatment was considered successful if the wounds had healed completely within three months without signs of infection and no additional amputation within six months. Results: The treatment success rate was 82.1% (n=32); 12.8% (n=5) required additional amputation and 5.1% (n=2) showed delayed wound healing. Bacterial growth was confirmed in 82.1% (n=32) with methicillin-resistant Staphylococcus aureus being the most commonly identified strain (23.1%, n=9). The lesions were divided anatomically into four groups; the largest number was the toes: (1) toes (41.0%, n=16), (2) metatarsals (35.9%, n=14), (3) midfoot (5.1%, n=2), and (4) hindfoot (17.9%, n=7). A significant difference in the Strauss wound score and TBI was observed between the treatment success group and failure group. Conclusion: The insertion of ALCSs can be a useful treatment option in diabetic foot infections with osteomyelitis. Low scores in the Strauss classification and low TBI are risk factors of treatment failure.