• Fisheries and Aquatic Sciences
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• 제22권12호
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• pp.30.1-30.11
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• 2019

Marine natural products isolated from the sponge Fascaplysinopsis cf reticulata, in French Polynesia, were investigated as an alternative to antibiotics to control pathogens in aquaculture. The overuse of antibiotics in aquaculture is largely considered to be an environmental pollution, because it supports the transfer of antibiotic resistance genes within the aquatic environment. One environmentally friendly alternative to antibiotics is the use of quorum sensing inhibitors (QSIs). Quorum sensing (QS) is a regulatory mechanism in bacteria which control virulence factors through the secretion of autoinducers (AIs), such as acyl-homoserine lactone (AHL) in gram-negative bacteria. Vibrio harveyi QS is controlled through three parallel pathways: HAI-1, AI-2, and CAI-1. Bioassay-guided purification of F. cf reticulata extract was conducted on two bacterial species, i.e., Tenacibaculum maritimum and V. harveyi for antibiotic and QS inhibition bioactivities. Toxicity bioassay of fractions was also evaluated on the freshwater fish Poecilia reticulata and the marine fish Acanthurus triostegus. Cyclohexanic and dichloromethane fractions of F. cf reticulata exhibited QS inhibition on V. harveyi and antibiotic bioactivities on V. harveyi and T. maritimum, respectively. Palauolide (1) and fascaplysin (2) were purified as major molecules from the cyclohexanic and dichloromethane fractions, respectively. Palauolide inhibited QS of V. harveyi through HAI-1 QS pathway at 50 ㎍ ml^-1 (26 μM), while fascaplysin affected the bacterial growth of V. harveyi (50 ㎍ ml^-1) and T. maritimum (0.25 ㎍). The toxicity of fascaplysin-enriched fraction (FEF) was evaluated and exhibited a toxic effect against fish at 50 ㎍ ml^-1. This study demonstrated for the first time the QSI potential of palauolide (1). Future research may assess the toxicity of both the cyclohexanic fraction of the sponge and palauolide (1) on fish, to confirm their potential as alternative to antibiotics in fish farming.

• IMMUNE NETWORK
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• 제14권1호
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• pp.38-44
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• 2014

K/BxN serum can transfer arthritis to normal mice owing to the abundant autoantibodies it contains, which trigger innate inflammatory cascades in joints. Little is known about whether gut-residing microbes affect host susceptibility to autoantibody-mediated arthritis. To address this, we fed C57BL/6 mice with water containing a mixture of antibiotics (ampicillin, vancomycin, neomycin, and metronidazol) for 2 weeks and then injected them with K/BxN serum. Antibiotic treatment significantly reduced the amount of bacterial genomic DNA isolated from fecal samples, in particular a gene encoding 16S ribosomal RNA derived from segmented filamentous bacteria. Arthritic signs, as indicated by the arthritic index and ankle thickness, were significantly attenuated in antibiotic-treated mice compared with untreated controls. Peyer's patches and mesenteric lymph nodes from antibiotic-treated mice contained fewer IL-17-expressing cells than those from untreated mice. Antibiotic treatment reduced serum C3 deposition in vitro via the alternative complement pathway. IL-$17^{-/-}$ congenic C57BL/6 mice were less susceptible to K/BxN serum-transferred arthritis than their wild-type littermates, but were still responsive to treatment with antibiotics. These results suggest that gut-residing microbes, including segmented filamentous bacteria, induce IL-17 production in GALT and complement activation via the alternative complement pathway, which cause the host to be more susceptible to autoantibody-mediated arthritis.

• 한국유기농업학회지
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• 제25권4호
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• pp.821-830
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• 2017

본 연구는 10종 허브 추출물에 대한 DPPH 자유라디칼 소거능, 항균효과 및 세포독성에 미치는 영향을 조사함으로써 항생제 대체제로서 활용 가능성을 위한 기초 자료로 제시하고자 수행하였다. 10종의 허브 추출물의 DPPH 자유라디칼 소거능은 로즈마리, 오레가노 및 캐모마일이 각 49.9, 48.9, 47.7%으로 유의적으로 가장 높았다. 허브 추출물의 E. coli K99와 S. typhimurium에 대한 항균활성은 베르가못, 오레가노, 타임과 로즈마리가 두 균주에 공통적으로 활성이 높게 측정되었으며, 활성이 나타나는 농도에서의 세포독성이 비교적 낮아 안전한 것으로 관찰되었다. 본 연구 결과 유기 축산을 위한 가축 내 천연 항생제 대체제로 항균 및 항산화 활성이 높고, 세포독성이 낮게 나타난 오레가노와 로즈마리가 천연물질로 활용 가능할 것으로 판단되며, 다양한 추출 조건으로 최적 추출 효율을 검토하여 추가적인 생리활성물질 검정과 해당 물질에 대한 연구가 필요하다.

• 한국수산과학회지
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• 제48권6호
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• pp.904-912
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• 2015

There is a great deal of research interest regarding substitutes for antibiotics because of various obstacles to the efficacy and use of antibiotics. We isolated and analyzed diversity of microbiota which exhibited antibacterial activity against 23 pathogenic bacteria, to develop alternative agent of antibiotics. By investigating the microbiota from rocks on the seashore, we characterized and obtained various antibacterial material-producing bacteria. Thirty-one isolates belong to four genera and seven species, according to 16S rDNA sequence analysis, showed antibacterial activities against 23 pathogenic bacteria. The Identity of 16S rDNA sequences indicated three species of Bacillus, one species of Paenibacillus, one species of Pseudomonas and two species of Enterobacter. Two isolates were similar to Bacillus aerophilus, four isolates were similar to Bacillus pumilus, seven isolates were similar to Bacillus safensis, 15 isolates were similar to Paenibacillus polymyxa, respectively. In addition, one isolate was similar with Pseudomonas poae, one isolate was similar to Enterobacter asburiae, and one isolate was similar to Enterobacter ludwigii, respectively. Variations of antibacterial activity and level among the same species were indicated the diverse strains of isolates. Vibrio vulnificus showed the highest degree of growth inhibition by 29 isolates. Further studies regarding antibacterial materials and bacteria suggest that development of probiotic strains or alternative agents to antibiotics.

• Asian-Australasian Journal of Animal Sciences
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• 제18권11호
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• pp.1642-1645
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• 2005

This study was conducted to investigate the effects of Biotite V supplementation on growth performance, nutrients digestibility and blood constituents and to evaluate whether Biotite V could replace an antibiotics in growing pigs diet. One hundred twenty pigs with initial body weight of 18.35${\pm}$0.15 kg were used in a 28 days growth trial. Pigs were allotted to four treatments by sex and body weight in a randomized complete block design. There were six replicate pens per treatment and five pigs per pen. Four dietary treatments were: 1) NC (basal diet without antibiotics), 2) PC (basal diet+0.1% CTC), 3) NCBV (NC diet+0.5% 200 mesh Biotite V) and 4) PCBV (PC diet+0.5% 200 mesh Biotite V). Through the entire experimental period, ADG tented to increase in NCBV and PCBV treatments compared to NC and PC treatments respectively, but no significant differences were observed (p>0.05). ADFI was slightly lower in NCBV and PCBV treatments than that in NC and PC treatments without significant differences (p>0.05). Gain/feed in PC and PCBV treatments was improved significantly compared to NC treatment (p<0.05). N and Ca digestibilities were higher in PCBV treatments than those in PC treatment (p<0.05). DM and P digestibilities were not affected by the addition of Biotite V (p>0.05). RBC, HCT, Hb, lymphocyte and monocyte were increased numerically in NCBV and PCBV treatments compared to NC and PC treatments (p>0.05). WBC was lower in treatment groups than that in NC treatment, but no significant differences were observed (p>0.05). In conclusion, dietary supplementation of Biotite V can better the gain/feed and some of the nutrients digestibilities in growing pigs. It has a possibility to replace antibiotics in swine diet.

• 농업과학연구
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• 제43권1호
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• pp.14-20
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• 2016

One of the most powerful health management practices is the use of antibiotics, but their use is being restricted because of health safety issues. The swine industry has been looking for various alternatives to antibiotics and increasingly considers the use of dietary factors like feed ingredients, feed additives, feed formulation practices, or feeding methods, instead of using antibiotics to improve pig health and performance. Among other alternatives to antibiotics, spray-dried plasma may be a candidate. Spray-dried plasma is a blood product that provides bioavailable nutrients and physiologically active components such as immunoglobulins, glycoproteins, growth factors, peptides, etc. It is an excellent protein source with balanced and highly digestible amino acids. Several beneficial physiological activities depend on components of spray-dried plasma, such as immune competence (antibacterial activity), modulation of microbiota and/or immune system, integrity of intestinal barrier function, etc. These beneficial effects can contribute to improvement of pig performance and health by modulation of microbiota in the digestive tract and/or immune system. Therefore, it is suggested that spray-dried plasma has great potential as an antibiotics alternative.

• 유기물자원화
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• 제15권1호
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• pp.123-133
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• 2007

항생제 사용의 증가와 무분별한 사용으로 인한 항생제 오남용은 항생제 내성균 증가와 더불어 미생물 종의 변화 및 수질환경에 독성물질로써 작용할 수 있다. 특히 항생제는 생물학적 폐수처리 공정에서 미생물에 의한 하 폐수 처리의 효율성 문제를 가져올 수 있다. 본 연구에서는 축산업에서 가장 많이 사용되는 항생제로 조사된 Oxytetracycline(OTC) 항생제가 축산폐수의 생물학적 처리과정에서 질산화와 유기물 제거효율에 미치는 영향을 살펴보았다. 항생제가 축산폐수의 처리효율에 미치는 영향을 살펴보기 위해서 회분식 시험과 $A_2/O$(Anoxic-Anoxic-Oxic) 시스템을 이용하였다. 향후 항생제를 다량 함유하고 있는 축산폐수를 처리할 수 있는 축산폐수처리시스템에 대해서 연구하고자 한다.

• 대한중풍순환신경학회지
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• 제8권1호
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• pp.58-62
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• 2007

Objective : Stroke patients tend to take antibiotics due to infection resulting from complication. One of many side effects from using antibiotics is diarrhea, which infact causes anaerobic organism dysfunction resulting Pseudo-Membranous Colitis (P.M.C). To treat P.M.C, antibiotics and antibacterial agents are usually used. But they may cause other side effects, therefore extreme caution must be taken. Methods : We treated an antibiotic induced P.M.C patient who diagnosed by sigmoid scopy with only Yijoong-tang (Lizhong-tang) without antibiotics and observed patients stool aspects. Results and Conclusion : Patiensts symptom was improved after 7days, and we can see the improvement by follow-up sigmoid scopy. This case may give us a possibility of that oriental medical treatments as complementary and alternative medicine to standard antibiotic treatment.

• 농업과학연구
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• 제44권2호
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• pp.181-187
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• 2017

The use of practical management factors to maximize pig health improvement cannot guarantee freedom from diseases. Moreover, because of health safety concerns, the use of antibiotics has been restricted in livestock, including pigs. Therefore, the swine industry has been looking for various alternatives to antibiotics to improve pig's health and performance. Clay is a dietary factor generally accepted for improving pig health. It is a naturally occurring material and is primarily composed of fine-grained minerals. It has a specific structure with polar attraction. Because of this structure, clay has the ability to lose or gain water reversibly. In addition, clay has beneficial physiological activities. First, clay has anti-diarrheic and antibacterial effects by penetrating the cell wall of bacteria or inhibiting their metabolism. Second, it can protect the intestinal tract by absorbing toxins, bacteria, or even viruses. When added to the diet, clay has also been known to bind some mycotoxins, which are toxic secondary metabolites produced by fungi, namely in cereal grains. Those beneficial effects of clay can improve pigs' health and performance by reducing pathogenic bacteria, especially pathogenic Escherichia coli, in the intestinal tract. Therefore, it is suggested that clay has a remarkable potential as an antibiotics alternative.

• 동의생리병리학회지
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• 제26권6호
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• pp.886-893
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• 2012

Methicillin-Resistant Staphylococcus aureus (MRSA) is a cephalosporin and beta-lactam antibiotic-resistant strain. In most cases, MRSA is spread from infected patients and infection rates are growing increasingly. Furthermore, increased resistance to antibiotics is causing serious problems in the world. Staphylococcus aureus is responsible for both nosocomial and community-based infections that range from relatively minor skin and soft tissue infections to life-threatening systemic infections. Therefore, there is a need to develop alternative antimicrobial drugs for the treatment of infectious diseases. In this study, we investigated antimicrobial activity of oriental medicine prescription against MRSA. The minimum inhibitory concentration (MIC) of Sohamhyung-tang water extract against S. aureus strains ranged from 500 to 2,000 ${\mu}g/mL$, so we have it confirmed that a strong antibacterial effect. Also, the combinations of Sohamhyung-tang water extract and conventional antibiotics exhibited improved inhibition of MRSA with synergy effect. We suggest that Sohamhyung-tang water extract against MRSA have antibacterial activity, it has potential as alternatives to antibiotic agent. We suggest that the Sohamhyung-tang water extract lead the treatment of bacterial infection to solve the resistance and remaining side-effect problems that are the major weak points of traditional antibiotics.