• Archives of Pharmacal Research
• /
• 제13권1호
• /
• pp.43-50
• /
• 1990

Conformational free energy calculations using an empirical potential function (ECEPP/2) and hydration shell model were carried out on the four-4-aminodiphenyl sulfone analogues of 4, 4'-diamino-2' methyldiphenyl sulfone, 4, 2', 4-triaminodiphenyl sulfone, 4, 4'-diaminodiphenyl sulfone, and 4-aminodiphenyl sulfone as antibacterial agents on Mycobacterium lufu. The conformational energy was minimized from starting conformations which included possible combinations of torsion angles in the molecule. The conformational entropy change of each conformation was computed using a harmonic approximation. To understand the hydration effect on the conformation of the molecule in aqueous solution, the contributions of water-accessible volume and the hydration free energy of each group or atom in the lowest-free-energy conformation was calculated and compared each other. From comparison of the computed lowest-free-energy conformations of four analogues with their antibacterial activities, it is known that the conformation and the hydrophobicity of sulfonyl group and its adjacent carbon atom in each compound are the essential factors to show the strong antibacterial activity.

• 한국결정성장학회지
• /
• 제33권5호
• /
• pp.187-190
• /
• 2023

본 연구에서는 ZnO-Na₂O-B₂O₃-SiO₂ 계 유리에 CaO의 첨가에 따른 유리의 열적, 화학적 특성, 표면 제타전위 및 항균특성을 분석하였다. 유리 조성에 따른 열적 특성은 DTA 분석을 통해 확인하였고, 30ZnO-xCaO-20Na₂O-30B₂O₃-(20-x)SiO₂ (x = 0, 2, 4, 6, 8, 10 mol%)계 유리에서 CaO 함량이 증가함에 따라 유리전이온도가 줄어드는 것을 확인하였다. CaO 함량이 늘어날수록 유리 구조가 약화됨에 따라 더 많은 Zn²⁺ 이온이 용출되었고, 알칼리 및 알칼리 토류의 초기 급속한 용출로 인해 유리의 표면 제타전위가 증가함을 확인하였다. 이러한 이유로 유리의 항균활성 또한 급격하게 개선됨을 확인하였으며, 대장균(gram negative)과 황색포도상구균(gram positive) 모두에 대해 99.9 % 항균 활성을 갖는 항균 유리를 개발할 수 있었다.

• Journal of the Korean Wood Science and Technology
• /
• 제31권1호
• /
• pp.16-21
• /
• 2003

느릅나무 근피의 메탄올 추출물을 분획하여 항균성을 측정한 결과 항균력이 가장 우수한 수용성 분획을 silicagel column chromatograpy 및 TLC에 의해 분리·정제한 다음 정제 화합물을 UV, IR, ¹H-NMR, ¹³C-NMR를 사용하여 구조를 동정하고 그 화합물의 항균력을 검정하였다. 수용성 분획물로부터 두 종류의 정제 화합물을 단리하였다. 기기분석 결과, 화합물 B는 Catechin rhamnoside로 확인되었다. 단리된 정제화합물은 Staphylococcus aureus 및 Salmonella typhimurium에 대하여 항균활성을 나타내었다.

• 한국식품영양학회지
• /
• 제36권5호
• /
• pp.354-359
• /
• 2023

A mono-type glycerine fatty acid ester compound was chemically synthesized using medium-chain fatty acids with antibacterial activity, and the physicochemical quality and antibacterial activity of the synthesized glycerine medium-chain fatty acid ester compound were measured. At a reaction molar ratio of MCT(medium chain triglyceride) to glycerine of 1:2.5, 48.15% mono ester was produced. The physicochemical analysis of the synthesized glycerine fatty acid ester compound showed an acid content of 0.38~0.60%, which tended to increase slightly as the glycerine molar ratio increased. The saponification value decreased as the synthesized molar ratio of glycerine increased from 218 to 284. The number of bacteria was measured to confirm the degree of antibacterial activity of glycerine medium-chain fatty acid esters against food poisoning bacteria, Bacillus cereus and Salmonella typhi. The number of bacteria significantly decreased as the MCT:glycerine molar ratio increased. In particular, the antibacterial effect between the treatment groups was the highest when at an MCT:glycerine molar ratio of 1:2.5.

• 치위생과학회지
• /
• 제23권4호
• /
• pp.389-395
• /
• 2023

Background: Dental caries prevention is a key research focus in dentistry, requiring advancements in the formulation of dental sealants. This study investigated the physical and antibacterial attributes of dental sealant enriched with phytoncide. Methods: Phytoncide was mixed with a commercially available dental sealant (Clinpro) at concentrations of 0 (control), 1.5%, 3%, and 4.5% by weight (wt%). The flexural strength, curing depth, and wettability of the dental sealant were measured. Antibacterial properties against Streptococcus mutans were evaluated through the enumeration of colony-forming units. Statistical analyses employed one-way variance analysis followed by Tukey's test (p<0.05). Results: The dental sealant containing 3% phytoncide showed no significant difference in flexural strength and curing depth compared with that in the control group (p>0.05). The flexural strength and curing depth decreased with increasing phytoncide content and significantly differed in sealant containing 4.5 wt% phytoncide (p<0.05). Wettability did not differ between the experimental and control groups (p>0.05). The antibacterial properties of the sealant containing 1.5% phytoncide were the same as those of the control group (p>0.05). The bacterial viability was significantly reduced in groups containing 3% and 4.5% phytoncide compared with that in the control group (p<0.05). Conclusion: Dental sealants incorporating phytoncide have a promising potential as antibacterial dental materials.

• 대한약침학회지
• /
• 제26권3호
• /
• pp.265-275
• /
• 2023

Objectives: The aim of this study was to evaluate the effect of fruit juices on Multi-Drug Resistant (MDR) bacterial pathogens involved in Urinary Tract Infections (UTIs) and Sexually Transmitted Infections (STIs) among tribal women in the district Anuppur, Madhya Pradesh, India. Methods: Fresh juices of lemon (Citrus limon), amla/Indian gooseberry (Phyllanthus emblica), pineapple (Ananas comosus), mosambi/sweet lime (Citrus limetta), orange (Citrus sinensis), kiwi (Actinidia deliciosa), and pomegranate (Punica granatum) fruits were evaluated for in vitro antibacterial activity against bacterial pathogens involved in UITs and STIs among tribal women. Physico-chemical analysis of fresh fruits was also carried out by measuring the pH, moisture, protein, fat, crude fibre, carbohydrate, and ascorbic acid content. Results: Lemon and amla juice showed better antibacterial activity against the pathogens as compared to other juices. MIC results fruit juices against UTIs and STIs pathogens vary depending on the specific pathogen and juice chemical constituents. The physico-chemical analysis showed that the moisture content was highest in mosambi (90%), followed by orange (87%). Ascorbic acid content was found highest in amla (540 mg/100 g), followed by kiwi (90.3 mg/100 g). Pomegranate showed highest concentration of carbohydrate (15.28 g/100 g), fat (1.28 g/100 g), and protein (1.65 g/100 g). Lemon juice had lowest pH of 2.20, followed by amla 2.67. Conclusion: The lemon juice showed highest antibacterial activity against MDR bacterial pathogens involved in UTIs and STIs among tribal women in district Anuppur, Madhya Pradesh, India. The low pH of lemon may be responsible for its high antibacterial activity as compared to other juices.

• Journal of Microbiology and Biotechnology
• /
• 제13권2호
• /
• pp.292-300
• /
• 2003

Pseudomonas fluorescens B16 is a plant glowth-prornoting rhizobacterium, which produces an antibacterial compound that is effective against plant root pathogens, such as Agrobacrerium tumefaciens and Raistonia solanacearum. We mutagenized the strain B16 with Omegon-Km and isolated six antibacterial-activity-deficient mutants. Two cosmid clones that hybridized with the mutant clones also were isolated from a genomic library of tile parent strain. Using deletion and complementation analyses, it was found that the biosynthesis genes resided in a 4.3-kb SalI-NarI fragment. When a plasmid clone carrying the fragment was introduced into P. fluorescens strain 1855.344, which does not exhibit any antibacterial activity, the transconjugants exhibited antibacterial activity, indicating that the plasmid clone carried all the genes essential for production of the antibacterial compound. DNA sequence analysis of the fragment identified four putative open reading frames (ORFs): orf1 through orf4 The deduced amino acid sequences of ORF1, ORF2, and ORF4 were similar to cystathionine gamma lyase, pyruvate formate-lyase activating enzyme, and transcriptional regulator, respectively, yet the amino acid sequence of ORF3 showed no similarities to any known proteins. It was also demonstrated that the antibacterial activity was responsible for biological control of the bacterial wilt caused by R. solanacearum.

• Journal of Microbiology and Biotechnology
• /
• 제23권2호
• /
• pp.225-236
• /
• 2013

Among several bacteria examined, an antibacterial-producing Lactobacillus strain with probiotic characteristics was selected and identified based on 16S rRNA gene sequencing. Subsequent purification and mode of action of the antibacterial compounds on target cells including E. coli were investigated. Maximum production of the antibacterial compound was recorded at 18 h incubation at $30^{\circ}C$. Interestingly, antibacterial activity remained unchanged after heating at $121^{\circ}C$ for 45 min, 24 h storage in temperature range of $70^{\circ}C$ to room temperature, and 15 min exposure to UV light, and it was stable in the pH of range 2-10. The active compounds were inactivated by proteolytic enzymes, indicating their proteinaceous nature, and, therefore, referred to as bacteriocin-like inhibitory substances. Isolation and partial purification of the effective agent was done by performing ammonium sulfate precipitation and gel filtration chromatography. The molecular mass of the GFC-purified active compound (~3 kDa) was determined by Tris-Tricine SDS-PAGE. To predict the mechanisms of action, transmission electron microscopy (TEM) analysis of ultrathin sections of E. coli before and after antibacterial treatment was carried out. TEM analysis of antibacterial compounds-treated E. coli demonstrated that the completely altered bacteria appear much darker compared with the less altered bacteria, suggesting a change in the cytoplasmic composition. There were also some membrane-bound convoluted structures visible within the completely altered bacteria, which could be attributed to the response of the E. coli to the treatment with the antibacterial compound. According to the in vivo experiments oral administration of L. plantarum HKN01 resulted in recovery of infected BALB/c mice with Salmonella enterica ser. Typhimurium.

• 한국미생물·생명공학회지
• /
• 제31권2호
• /
• pp.191-196
• /
• 2003

본 연구는 김치로부터 분리한 젖산균의 다양성과 항균성을 조사하기 위하여 수행되었다. 희석한 김치 국물을 CaCO$_3$가 첨가된 MRS 고체 배지에 도말 한 후, $25^{\circ}C$에서 2일 동안 배양하여 여러 가지 김치로부터 27가지의 젖산균을 분리하였다. 이렇게 분리한 젖산균들을 Bergey 분류법과 BPB 배지를 통한 생화학적인 방법과 16S rDNA PCR을 이용한 분자 생물학적인 방법으로써 분석하였다. 그러나 이들 방법으로 분석한 결과가 일치하지 않은 경우가 많았다. 이들 분리 젖산균은 16S rDNA 부분 염기서열을 결정한 결과 Leuconostoc mesenteriodes(11균주), Leu. carnosum(3균주), Lactobacillus curvatus(8균주), Lac. pentosus(2균주), Weisselia kimchi(1균주), W. cibaria(1균주), Pediococcus pentosaceus(1균주) 등의 것과 각각 매우 유사한 것으로 분석되었다. 이들중 Leu. carnosum은 이전에 김치에서 분리되었다고 보고된 바가 없다. 그리고 이들 김치에서 분리 동정한 균들의 항균작용 활성을 검사 해 본 결과 균주에 따라서 활성의 정도는 다르게 나타났으나 Bacillus subtilis, Escherichia coli, Salmonella enteritidis, S. paratyphica, S. typhi, Staphylococcus aureus, Shigella boydii, S. sonnei 등에 대해 뚜렷한 항균효과를 나타내었다.

• Bulletin of the Korean Chemical Society
• /
• 제31권4호
• /
• pp.793-797
• /
• 2010

A series of 2-aminothiazoles derivatives have been synthesized and tested for in vitro antibacterial activity on different microorganisms. Syntheses have been carried out following simple methodology in excellent isolated yields. The structure and purity of the original compounds were confirmed by IR, NMR, Mass spectroscopy, and elemental analysis. All compounds were tested for antibacterial activity against S. aureus, S. pyogenes, E. coli, P. aeruginosa, S. typhi and V. parahaemolyticus. These preliminary results indicate that some of compounds are exhibiting good activity.