• Journal of Microbiology and Biotechnology
• /
• 제33권9호
• /
• pp.1111-1118
• /
• 2023

As a long-term condition that affects the airways and lungs, chronic obstructive pulmonary disease (COPD) is characterized by inflammation, emphysema, breathlessness, chronic cough, and sputum production. Currently, the bronchodilators and anti-inflammatory drugs prescribed for COPD are mostly off-target, warranting new disease management strategies. Accumulating research has revealed the gut-lung axis to be a bidirectional communication system. Cigarette smoke, a major exacerbating factor in COPD and lung inflammation, affects gut microbiota composition and diversity, causing gut microbiota dysbiosis, a condition that has recently been described in COPD patients and animal models. For this review, we focused on the gut-lung axis, which is influenced by gut microbial metabolites, bacterial translocation, and immune cell modulation. Further, we have summarized the findings of preclinical and clinical studies on the association between gut microbiota and COPD to provide a basis for using gut microbiota in therapeutic strategies against COPD. Our review also proposes that further research on probiotics, prebiotics, short-chain fatty acids, and fecal microbiota transplantation could assist therapeutic approaches targeting the gut microbiota to alleviate COPD.

• Molecules and Cells
• /
• 제46권10호
• /
• pp.637-653
• /
• 2023

The physiology of most organisms, including Drosophila, is heavily influenced by their interactions with certain types of commensal bacteria. Acetobacter and Lactobacillus, two of the most representative Drosophila commensal bacteria, have stimulatory effects on host larval development and growth. However, how these effects are related to host immune activity remains largely unknown. Here, we show that the Drosophila development-promoting effects of commensal bacteria are suppressed by host immune activity. Mono-association of germ-free Drosophila larvae with Acetobacter pomorum stimulated larval development, which was accelerated when host immune deficiency (IMD) pathway genes were mutated. This phenomenon was not observed in the case of mono-association with Lactobacillus plantarum. Moreover, the mutation of Toll pathway, which constitutes the other branch of the Drosophila immune pathway, did not accelerate A. pomorum-stimulated larval development. The mechanism of action of the IMD pathway-dependent effects of A. pomorum did not appear to involve previously known host mechanisms and bacterial metabolites such as gut peptidase expression, acetic acid, and thiamine, but appeared to involve larval serum proteins. These findings may shed light on the interaction between the beneficial effects of commensal bacteria and host immune activity.

• Asian-Australasian Journal of Animal Sciences
• /
• 제26권2호
• /
• pp.266-274
• /
• 2013

The effect of different phytogenic feed additives on reducing odorous compounds in swine was investigated using in vitro fermentation and analyzed their microbial communities. Soybean meal (1%) added with 0.1% different phytogenic feed additives (FA) were in vitro fermented using swine fecal slurries and anaerobically incubated for 12 and 24 h. The phytogenic FAs used were red ginseng barn powder (Panax ginseng C. A. Meyer, FA1), persimmon leaf powder (Diospyros virginiana L., FA2), ginkgo leaf powder (Ginkgo biloba L., FA3), and oregano lippia seed oil extract (Lippia graveolens Kunth, OL, FA4). Total gas production, pH, ammonianitrogen ($NH_3$-N), hydrogen sulfide ($H_2S$), nitrite-nitrogen ($NO_2{^-}$-N), nitrate-nitrogen ($NO_3{^-}$-N), sulfate (${SO_4}^{--}$), volatile fatty acids (VFA) and other metabolites concentration were determined. Microbial communities were also analyzed using 16S rRNA DGGE. Results showed that the pH values on all treatments increased as incubation time became longer except for FA4 where it decreased. Moreover, FA4 incubated for 12 and 24 h was not detected in $NH_3$-N and $H_2S$. Addition of FAs decreased (p<0.05) propionate production but increased (p<0.05) the total VFA production. Ten 16S rRNA DGGE bands were identified which ranged from 96 to 100% identity which were mostly isolated from the intestine. Similarity index showed three clearly different clusters: I (FA2 and FA3), II (Con and FA1), and III (FA4). Dominant bands which were identified closest to Eubacterium limosum (ATCC 8486T), Uncultured bacterium clone PF6641 and Streptococcus lutetiensis (CIP 106849T) were present only in the FA4 treatment group and were not found in other groups. FA4 had a different bacterial diversity compared to control and other treatments and thus explains having lowest odorous compounds. Addition of FA4 to an enriched protein feed source for growing swine may effectively reduce odorous compounds which are typically associated with swine production.

• 한국응용곤충학회지
• /
• 제48권3호
• /
• pp.385-392
• /
• 2009

Xenorhabdus nematophila (Xn)와 Photorhabdus tempeerata subsp. temperata (Ptt)의 곤충병원세균을 배추좀나방(Plutella xylostella)의 혈강에 주입할 경우 높은 병원력을 보였다. 본 연구는 이들 세균 배양액의 섭식 처리에 따른 배추좀나방에 대한 병원성 유기를 조사하였다. 세균 배양액만을 이용하여 배추좀나방 3령충에 섭식 처리한 결과 뚜렷한 병원성을 유발하지 못하였으나, Bacillus thurigiensis(Bt) 와 혼합 처리하였을 때 높은 Bt 병원성 제고 효과를 나타냈다. 물질 추적을 위해서 이 세균 배양액을 유기 용매를 이용하여 헥산, 에틸아세테이트 및 수용액 추출 분획구로 분리하였다. 대부분이 Bt 상승효과는 에틸아세테이트 추출 분획구에서 나타났다. Thin layer chromatography 분석 결과는 에틸아세테이트 분획구가 대사물질을 포함하고 있으며, 이들이 헥산 또는 수용액 추출 분획구에 포함된 물질과는 상이하다는 것을 나타냈다. 이러한 결과는 이들 곤충병원세균이 Bt 병원성을 제고시키는 물질을 생산하고 배양액으로 분비한다고 제시하고 있다.

• Journal of Microbiology and Biotechnology
• /
• 제27권10호
• /
• pp.1763-1772
• /
• 2017

This study aimed to isolate and characterize antibacterial metabolites from Pharbitis nil seeds and investigate their antibacterial activity against various plant pathogenic bacteria. The methanol extract of P. nil seeds showed the strongest activity against Xanthomonas arboricola pv. pruni (Xap) with a minimum inhibition concentration (MIC) value of $250{\mu}g/ml$. Among the three solvent layers obtained from the methanol extract of P. nil seeds, only the butanol layer displayed the activity with an MIC value of $125{\mu}g/ml$ against Xap. An antibacterial fraction was obtained from P. nil seeds by repeated column chromatography and identified as pharbitin, a crude resin glycoside, by instrumental analysis. The antibacterial activity of pharbitin was tested in vitro against 14 phytopathogenic bacteria, and it was found to inhibit Ralstonia solanacearum and four Xanthomonas species. The minimum inhibitory concentration values against the five bacteria were $125-500{\mu}g/ml$ for the n-butanol layer and $31.25-125{\mu}g/ml$ for pharbitin. In a detached peach leaf assay, it effectively suppressed the development of bacterial leaf spot, with a control value of 87.5% at $500{\mu}g/ml$. In addition, pharbitin strongly reduced the development of bacterial wilt on tomato seedlings by 97.4% at $250{\mu}g/ml$, 7 days after inoculation. These findings suggest that the crude extract of P. nil seeds can be used as an alternative biopesticide for the control of plant diseases caused by R. solanacearum and Xanthomonas spp. This is the first report on the antibacterial activity of pharbitin against phytopathogenic bacteria.

• 미생물학회지
• /
• 제30권1호
• /
• pp.53-59
• /
• 1992

자연계로부터 4-chlorobiphenyl (4CB) 을 분해하는 P08, P20, 027 그리고 P1242 균주를 불리하였다. 이들 분해 균주들의 4CB 분해 과정을 UV-spectrophotometry 방법으로 분석한 결과, 4-CB 로 부터 2-hydroxy-6-oxo-6-(4'-chlorophenyl)hexa-2, 4-dienoic acid 와 4-chlorobenzoate(4CBA) 가 생성되었다. 따라서 분해균주들은 공통적으로 meta-cleavage pathway에 의하여 4CB 를 분해하는 것으로 확인되었다. 그러나 DJ-12, P08 그리고 P27 균주는 4CBA 를 계속 분해하여 4-hydroxybenzoate 를 생성하였으나, P20 과 P1242 균주들은 4CBA 를 더이상 분해하지 못 하였다. 각 분해 균주에서 cbp 유전자군의 상동성을 분석하기 위하여 P. pseudoalcaligenes KF707 의 bphABC 유전자군을 DNA probe 로 이용하여 Southern hybridization 을 실시한 결과, DJ-12, P08 그리고 P27 균주들은 XhoI 에 의한 2.2kb 와 1.8 kb, 그리고 EcoRI 에 의한 11 kb 의 genomic DNA 의 절편에서 hybridization 이 일어났다. 따라서 본 연구에서 분리한 4CB 분해 균주들의 cbp 유전자군은 분해경로 및 bph 유전자군과의 상동성에 의거하여 부 group 으로 구분되었다.

• 농약과학회지
• /
• 제18권4호
• /
• pp.422-428
• /
• 2014

딸기 근권에서 분리한 내생균 중 고추역병균 방제 및 고추생육촉진 효과가 우수한 균주를 선발하였다. Pseudomonas fluorescen EP103으로 명명된 내생균주는 다른 내생균주와 비교하여 식물의 뿌리 길이와 생체 중이 크게 증가하였다. 고추역병에 대한 온실검정에서 EP103처리는 방제가 78.7%을 나타냈으며 항균력 실험결과 고추역병균을 직접 억제하지는 않았다. EP103이 처리된 고추에서는 PR1, PR10등의 병저항성 유전자가 발현되었으며 EP103의 PCR분석 결과 피올테오린, 파이로니트린, 하이드로젠 싸이아나이드, 오르화미드 등의 유용유전자를 함유하고 있음이 밝혀졌다. 따라서 본 균주는 고추역병의 생물 방제용으로 활용할 가치가 있는 것으로 판단된다.

• Journal of Microbiology and Biotechnology
• /
• 제30권4호
• /
• pp.571-582
• /
• 2020

Quorum sensing (QS)-mediated infections cause severe diseases in human beings. The control of infectious diseases by inhibiting QS using antipathogenic drugs is a promising approach as antibiotics are proving inefficient in treating these diseases. Marine fungal (Pestalotiopsis sydowiana PPR) extract was found to possess effective antipathogenic characteristics. The minimum inhibitory concentration (MIC) of the fungal extract against test pathogen Pseudomonas aeruginosa PAO1 was 1,000 ㎍/ml. Sub-MIC concentrations (250 and 500 ㎍/ml) of fungal extract reduced QS-regulated virulence phenotypes such as the production of pyocyanin, chitinase, protease, elastase, and staphylolytic activity in P. aeruginosa PAO1 by 84.15%, 73.15%, 67.37%, 62.37%, and 33.65%, respectively. Moreover, it also reduced the production of exopolysaccharides (74.99%), rhamnolipids (68.01%), and alginate (54.98%), and inhibited the biofilm formation of the bacteria by 90.54%. In silico analysis revealed that the metabolite of P. sydowiana PPR binds to the bacterial QS receptor proteins (LasR and RhlR) similar to their respective natural signaling molecules. Cyclo(-Leu-Pro) (CLP) and 4-Hydroxyphenylacetamide (4-HPA) were identified as potent bioactive compounds among the metabolites of P. sydowiana PPR using in silico approaches. The MIC values of CLP and 4-HPA against P. aeruginosa PAO1 were determined as 250 and 125 ㎍/ml, respectively. All the antivirulence assays were conducted at sub-MIC concentrations of CLP (125 ㎍/ml) and 4-HPA (62.5 ㎍/ml), which resulted in marked reduction in all the investigated virulence factors. This was further supported by gene expression studies. The findings suggest that the metabolites of P. sydowiana PPR can be employed as promising QS inhibitors that target pathogenic bacteria.

• Asian-Australasian Journal of Animal Sciences
• /
• 제31권10호
• /
• pp.1643-1653
• /
• 2018

Objective: This study investigated the effect of dietary crude protein (CP) supplementation on nutrient intake, nitrogen (N) utilisation, blood metabolites, ruminal fermentation and growth performance of young Holstein bulls. Methods: Twenty-one young bulls weighing $277{\pm}11.2kg$ were equally divided into three groups and were offered diets formulated with low CP (LCP; 10.21% CP and 4.22% rumen degradable protein [RDP]), medium CP (MCP; 12.35% CP and 5.17% RDP) and high CP (HCP; 14.24% CP and 6.03% RDP). Yellow corn silage was used as a unique forage source and was mixed with concentrate. This mixed feed was given ad libitum to the young bulls included in the study. Results: Results showed that CP intake, blood urea nitrogen, N intake, total N excretion and N balance increased linearly with an increase in dietary CP level (p<0.05). However, no significant difference was observed in nutrient digestibility among the bulls receiving the different diets. Ruminal pH (p<0.05) and ammonia nitrogen ($NH_3-N$) concentration (p<0.01) were significantly higher in the bulls receiving the MCP and HCP diets than in those receiving the LCP diet. The bulls receiving the HCP diet showed significantly higher ruminal bacterial protein level, propionate, acetate and total volatile fatty acid (TVFA) concentrations than bulls receiving the LCP diet (p<0.05). Moreover, dietary CP level exerted a significant positive effect on the final body weight, average daily gain and gain-to-feed ratio of the bulls (p<0.05). Conclusion: High dietary CP level is optimal for achieving maximum growth and high profitability without exerting a negative effect on the physiology of growing Holstein bulls.

• 문화기술의 융합
• /
• 제8권6호
• /
• pp.935-941
• /
• 2022

본 연구의 목적은 과채류 복합추출물에 소량의 홍삼을 첨가하여 증숙가열 및 유산균 발효에 의한 진세노사이드 대사산물의 활성 증가와 장내면역 활성이 현저히 개선되는지를 알아보고자 하였다. 홍삼 단독 추출물 또는 과채류복합추출물에 비해 홍삼을 함유한 과채류 복합추출물에서 시너지 효과에 의한 장내면역 활성의 증가가 관찰됨을 확인하였다. 다음으로 홍삼을 함량별로 첨가하여 유산균 발효에 따른 시너지 효과를 얻을 수 있는 홍삼의 농도를 결정하였다. 그 결과, 홍삼을 과채류 혼합물 질량에 대하여 3~10%의 질량비로 혼합하여 증숙 및 유산균 발효 추출하였을 때 시너지 효과가 나타나는 것을 확인하였다. 또한 홍삼을 함유한 과채류 복합추출물은 200㎍/ml의 농도로 처리하였을 때 홍삼이 함유되지 않은 과채류 복합추출물에 비해 NO 생성을 약 60% 억제하였으며, IL-1β의 발현은 63%, IL-6의 발현 69%, TNF-α의 발현 76% 수준으로 억제하여 장내면역 활성이 크게 향상되었음을 확인하였다.