Fowl typhoid (FT) is a septicemic disease caused by Salmonella Gallinarum (S. Gallinarum) and is responsible for severe economic losses in Korea. In this study, 49 aminoglycosides (AMG)-resistant S. Gallinarum were analyzed to determine the phenotypic and genotypic characteristics. Thirty-six (73.5%) out of 49 AMG-resistant S. Gallinarum exhibited resistance to at least one agent in three or more of antimicrobial categories as multidrug-resistant (MDR) isolates. Among the AMG-resistant isolates exhibiting MDR, 21 (58.3%) and 11 (30.6%) of the isolates harbored ant(2")-I, which encodes an aminoglycoside adenylyltransferase, and blaTEM-1, which is a β-lactamase-encoding gene, respectively. The qnrB, cmlA, and sul1 and sul2 genes, which are related to resistance to quinolones, chloramphenicol and sulfonamides, respectively, were detected in 8.3~22.2% of the AMG-resistant isolates that exhibited MDR. Twenty-four (66.6%) of 36 AMG-resistance S. Gallinarum exhibiting MDR carried class 1 integrons with aadA genes cassettes. Several plasmid replicon types, such as B/O, FIIA, FIB, and Frep were considered to play a prominent role in S. Gallinarum, and the presence of these genetic characteristics remain a serious concern to the selection of antimicrobials for the treatment of FT.

본 연구에서는, 표고버섯 균사체 발효 생물전환공법으로 생산된 미강생물전환소재(BPP-RB)가 가금티푸스의 주요 원인균인 S. Gallinarum에 감염된 닭 유래 대식세포주 HD- 11에 미치는 효과를 조사하였다. 그 결과, 미강생물전환소 재 추출액은 S. Gallinarum 277에 대한 직접적인 성장억제 효과를 보여주지 않았으며, 총단백질 및 분비단밸질 발현 양상에 어떠한 변화도 유도하지 못하였다. 하지만, 미강생 물전환소재 추출액은 (i) HD-11 대식세포의 탐식 능력 (phagocytic activity)을 활성화하였고, (ii) Th1-type cytokines (tumor necrosis factor-α, interleukin (IL)-1β, iNOS)과 immunosuppressive cytokine IL-10의 발현 증가를 유도하였으며, (iii) Th2-type cytokines (IL-4, IL-6)의 발현은 감 소시키는 것으로 확인되었다. 이러한 결과를 종합하면, 미강생물전환소재는 가금 농장에서 가금티푸스 및 다른 Salmonella종의 감염을 예방하기 위한 사료첨가제로서의 가능성을 가지고 있다고 사료된다.

The present study was investigated the antibacterial effect of several sodium salts and the sodium salt mixture composed with sodium chlorate, sodium azide and sodium cyanide on Salmonella gallinarum (S. gallinarum) infection in murine derived macrophage RAW 264.7 cells. In the infection assay of S. gallinarum in macrophage cells pretreated with 15 mM sodium chlorate, 0.3 mM sodium cyanide, 0.3 mM sodium azide and the sodium salt mixture (15 mM sodium chlorate, 0.3 mM sodium cyanide, 0.3 mM sodium azide), respectively, the numbers of S. gallinarum in all treated-groups tended to decrease in the process of time after treatment, but the group treated with sodium cyanide was no significant difference compared with control. After 24 hours of treatment, the number of S. gallinarum in sodium azide (p<0.05), sodium chlorate (p<0.001) and the sodium salt mixture (p<0.001) treated-group was significantly decreased compared with control, and that in the sodium salt mixture treated-group was decreased the higher than all groups. The results of this study demonstrated that the sodium salt mixture composed with sodium chlorate, sodium azide and sodium cyanide, has the antimicrobial activity for S. gallinarum and may be beneficial on the control of intracellular pathogens.

Antibacterial activity is an important feature for the development of antibiotics alternatives. Plant extract is considered as a promising alternative for organic farming. In this study, a total of 11 plants were extracted using ethanol to determine their antibacterial activities against to Staphylococcus aureus, Listeria monocytogens, Mannheimia haemolytica and Salmonella gallinarum. The synergistic interaction among plant extracts was also investigated. Plants used in this study were Carthamus nctoricus L. (pA), Poncirus trifollata Raf. (pB), Scutellaria balcalensis Georgi (pC) Prunus sargentii (pD), Cucurbita moschata DUCH Leaf (pE), Allium cepa L. peel (pF) Portulaca oleracea L. (pG), Xanthium strumarium L. (pH), Duchesnea chrysantha (pI), Cudrania tricuspidata (pJ) and Juniperus chinensis L. (pK). The pB and pA had the most broad antibacterial spectrum and the highest activity against to Staph. aureus among plant extract, respectively. In the synergistic interaction, the mixtures of pA and pC as well as pA and pF had batter antibacterial activity against to Staph. Aureus compared with other mixtures.