Well-dispersed Ag3VO4 nanoparticles @polyacrylonitrile (PAN) nanofibers were synthesized by an easily controlled, template-free method as a photo-catalyst for the degradation of methylene blue. Their structural, optical, and photocatalytic properties have been studied by X-ray diffraction, transmission electron microscopy, field-emission scanning electron microscopy equipped with rapid energy dispersive analysis of X-ray, photoluminescence, and ultraviolet–visible spectroscopy. The characterization procedures revealed that the obtained material is PAN nanofibers decorated by Ag3VO4 nanoparticles. Photocatalytic degradation of methylene blue investigated in an aqueous solution under irradiation showed 99% degradation of the dye within 75 min. Finally, the antibacterial performance of Ag3VO4 nanoparticles @PAN composite nanofibers was experimentally verified by the destruction of Escherichia coli. These results suggest that the developed inexpensive and functional nanomaterials can serve as a non-precious catalyst for environmental applications.

The effects of antioxidant measured by DPPH radical scavenger activity, the extract of harvestry in July shown highest activity(91.8±0.01%). The all extracts of 4 parts(leaf, f1ower, root, branch) of harvestry in July were shown better radical scavenger activity than BHT(89.2±0.01%). The antibacteria activity of Agrimonia pilosa extracts was determined by using a paper disc method against bacteria, the methanol extracts(70%) showed the most active antibacteria activity against 12 kinds of harmful microorganisms. The methanol extracts(70%) showed the highest antibacterial activity against S. aureus and B. subtilis. In addition, the minimum inhibitory concentration(MIC) of methanol extracts(70%) against S. aureus, B. subtilis, C. diphtheriae, S. mutans, and S. epidermidis were revealed 0.625~10mg/mL. As a result, antibacteria activity in methanol(70%) extract of Agrimonia pilosa shown higher gram positive bacteria than gram negative bacteria.

Lysozyme was the first humoral antibacterial factor to be studied in insects and it was considered the main immune factor in the haemolymph. Lysozymes are enzymes characterized by their ability to break down bacterial cell walls. We identified four lysozymes(c1, c2, c3, and I type)-encoding cDNAs from P. americana. It was deduced protein sequences are basic in nature, contain 138 amino acids(c1), 139 amino acids(c2), 141 amino acids(c3), and 143 amino acids(I) including conserved cysteine residues. Transcriptional profiles indicated that the predominant form is constitutively expressed and up-regulated upon immune challenge by heat stress. When injected lipoplysaccharide (LPS), lysozymes (I, c1, and c2) was up-regulated in the body. In addition, the expression levels of lysozymes(I, c1, and c2) in the P. americana significantly increased after two hour by injection of LPS. We were cloning and analysis of chitinase from B. germanica. The chitinase was deduced protein sequences are contain 539 amino acid residues long. The chitinase were up-regulated by injection of LPS in B. germanica. the expression levels of chitinase in the B. germanica significantly increased after four hour by injection of LPS. The cDNA encoding the chitinase of B. germanica was expressed as a 67-kDa band in the baculovirus-infected insect cells and the extracts of the recombinant baculovirus-infected cells showed anti-bacterial activity(0.0125㎍/㎖: 2.5±0.3, 0.00125㎍/㎖: 0.6±0.4mm) to C. albican on the plate.

가열하지 않은 간편섭취 농산물의 섭취를 통한 세균 감염의 가능성을 줄이고자, 가정에서 쉽게 구할 수 있고 잔류에 대한 염려가 없는 천연 항균성 식품을 이용하여 세척할 경우, 물 세척에 비해 세균의 감소효과가 있는지 확인하고자 하였다. 여러 가지 항균성 식품성분 중 마늘의 allicin, 생강의 gingerol, 녹차의 catechin, 계피의 cinnamic aldehyde, 고추냉이의 allyl isothiocyanate의 단계별 희석액으로 세척한 후, 단순 물 세척의 세척효과와 비교한 결과, 단순 물 세척에 비하여 세균 감소의 효과가 큰 것으로 통계적으로 확인되었다. 간편섭취 농산물에서 검출된 Bacillus cereus 오염의 유래 및 연관성을 확인하고자 유전적 상관성을 분석해 본 결과 유사도가 매우 높은 균주들이 많이 검출되었다. 이 사실을 통해 간편섭취 농산물의 생산, 가공, 포장, 유통 등의 과정에서 공통적인 요인에 의한 지속적인 오염의 가능성 및 소비자의 감염 가능성을 파악할수 있었으며, 감염을 예방하기 위한 사전적이고 체계적인 관리가 필요함을 확인하였다.

This study investigated the antibacterial effects of Galla rhois extract (GRE) against Campylobacter jejuni and Campylobacter coli. The minimum inhibitory concentrations (MICs) of GRE against C. jejuni and C. coli were 0.28 and 0.55 mg/mL, respectively, and the corresponding minimum bactericidal concentrations (MBCs) were 4.4 and 5.5 mg/mL. C. jejuni treated with the MIC, MBC or 2×MBC of GRE showed significant inhibition of growth compared with that of the control group during the incubation period, and no viable bacteria were detected at 24 h after incubation. C. coli treated with MIC, MBC or 2×MBC of GRE also showed inhibition of growth compared with that of the control group during the incubation period, and in the C. coli cultures treated with MBC and 2×MBC of GRE, no viable bacteria were detected at 24 h after incubation. In conclusion, GRE is a candidate antibacterial agent against C. jejuni and C. coli, and may have applications for the control of Campylobacter infection in poultry.

Abstract - We are aim to evaluate lysozyme and antibacterial activity of cultured catfish, Silurus asotus, that fed supplementally with Galla rhois extracts for eight weeks. Lysozyme activity in the spleen and serum of administrated group was higher than not administrated group, but in mucus of the lysozyme activity was no regular than other organ. The lysozyme activity of the spleen, kidney, serum of administrated fishes were increased after 2 weeks and that was highest after 8 weeks. Ht and GLU in serum of administrated fishes were gradually increased but GOT was decreased after 8 weeks. There is no significant differences in HB (Hemoglobin) and TP (Total Protein) each groups. Furthermore, there is no pathohistological changes of kidney and liver of tested fishes. The cumulative survival rates of administrated group after intraperitoneal injection of Aeromonas veronii with 6.5×106 cfu mL-1 was presented 33% in 9 days. As the Results, Galla rhois extracts has any beneficial effects for immunity elevation and antibacterial activity in catfish, Silurus asotus.

Synthesis of nanosilver particles were obtained by chemical reduction of silver nitrate and capping agent. The solution containing nanoparticles were coated on polyvinylidene fluoride (PVDF) hollow fiber membranes which the membranes were measured water permeation flux and antibacterial activities. The resonance peak of the Ag/PVA core shell nanoparticle indicated at 430 nm in the UV-visible spectra. The Ag/PVA coated PVDF membrane exhibited excellent antibacterial performance over 60 days, and water permeation flux (LMH) was observed from 700 to 1400.

본 연구는 마늘의 물추출물(AGE)의 E. coli O157:H7,S. typhimurium, 그리고 S. aureus에 대한 항균효과를 조사하였다. AGE의 E. coli O157:H7, S. typhimurium, and S.aureus에 대한 최소억제농도(MIC)는 각각 24, 48 그리고 24 mg/mL이었으며, 최소살균농도(MBC)는 모든 균에 대하여 96 mg/mL이었다. AGE 24 mg/mL을 E. coli O157:H7에 투여하고 배양 24시간 후에, 균의 증식이 무처리 대조군과 비교하여 유의성 있게 감소하였다(p < 0.01). 그러나 AGE 24 mg/mL을 S. aureus에 투여하고 배양 24시간 후에, 대조군과 비교하여 유의성 있는 균의 증식억제 효과가 나타나지 않았으나, AGE 96 mg/mL을 투여한 경우에서는 배양 24시간 후에 대조군과 비교하여 유의성 있는 균의 증식억제가 나타났다(p < 0.01). AGE 48 (p < 0.05)과 96 mg/mL (p < 0.001)을 S. typhimurim에 투여하고 24시간배양 후에, 대조군과 비교하여 통계적으로 유의성 있는 균의 증식억제 효과가 나타났다. 본 연구의 결과로부터, 마늘의 물추출물은 항생제와 화학적 식품보존제의 대체제로서 사용이 가능할 것으로 사료된다.

본 연구는 자몽종자추출물이 도포 포장지의 항균활성에 미치는 영향을 알아보았다. 저장 안전성 중 항균력을 확인 하기 위하여 그람 양성균(B. cereus, L. monocytogenes) 2종 과 그람 음성균(E. coli, S. enteritidis) 2종을 선택하였다. 자몽종자추출물의 농도별(60-5,000 ppm)에 따른 그람 양성 균의 투명환 크기는 최저 5 mm에서 최고 21 mm로 나타내 었다. 또한 그람 음성균의 투명환 크기는 최저 0 mm에서 최고 7 mm로 나타내었다. 자몽종자추출물을 농도별(60- 5,000 ppm)로 도포 포장시킨 경우 그람 양성균의 투명환 크기는 최저 5 mm에서 최고 19 mm로 나타내었다. 또한 그람 음성균의 투명환 크기는 최저 7 mm에서 최고 11 mm 로 나타내었다. 자몽종자추출물을 처리한 도포 포장지를 이용하여 즉석섭취 식품에 대한 저장 안정성을 알아본 결 과, GFSE의 농도(1,000, 5,000, 10,000 ppm) 차이에 따라 각각 11시간, 16시간, 18시간 동안 신선도가 유지 되었고, 일반 세균수 측정 결과, 1,000, 5,000 ppm 및 10,000 ppm 에서 각각 4.5 log CFU/g, 4.8 log CFU/g, 4.2 log CFU/g로 측정되어 저장성을 증가 시킴을 알 수 있었다.

It is known that bones get damaged by accidents and aging. Since the discovery of Bioglass, various kinds of ceramics have been also found to bond to living bone; some of these ceramics are already being clinically used as bone-repairing materials. In the present study, antibacterial calcium silicate gel (Ag-30CaO·70SiO2 gel) was prepared by sol-gel method in order to control the microstructure, which is related to the dissolution rate and induction period of apatite formation in body environment. In addition, biological Ag-30CaO·70SiO2 is tested. This was done to impart antimicrobial activity to the 30CaO·70SiO2. Ag ion was added during sol-gel synthesis to replace the H2O added during the making of the 30CaO·70SiO2 gel, which has silver solutions of various concentration. After the sol-gel process, 1N-HNO3 solution was used to wash the gel when synthesizing the gel, in order to maintain the porous structure and remove PEG, water soluble polymers. Then, the apatite forming ability of the sol-gel derived CaO-SiO2 gels was investigated using simulated body fluid (SBF), which had almost the same ion concentration as that of human blood plasma. The gels were analyzed by FT-IR spectroscopy, SEM observation, XRD, and fluorescent microscopy. The apatite was successfully created even after washing the gel; apatite is present in an amorphous state, and was found to affect the concentration of the Ag ion in cells in MC3T3 live & dead assay results. From these results, it is suggested that a good material that can be used to repair defects of nature bone is Ag-30CaO·70SiO2 gel.

Apolipophorin III (apoLp-III) is a multifunctional protein that is involved in lipid transport and innate immunity in insects. In this study, an apoLp-III protein that exhibits antibacterial activity was identified in honeybees (Apis cerana). A. cerana apoLp-III cDNA consists of 193 amino acids that share high protein sequence identity to other members of the hymenoptran insect apoLp-III family. A. cerana apoLp-III is expressed constitutively in the fat body, epidermis, and venom gland and is detected as a 23-kDa protein. A. cerana apoLp-III expression is induced in the fat body after injection with Escherichia coli, Bacillus thuringiensis, or Beauveria bassiana. However, recombinant A. cerana apoLp-III (expressed in baculovirus-infected insect cells) binds directly to E. coli and B. thuringiensis but not to B. bassiana. Consistent with these findings, A. cerana apoLp-III exhibited antibacterial activity against Gram-negative and Gram-positive bacteria. These results provide insight into the role of A. cerana apoLp-III during the innate immune response following bacterial infection.

This study was conducted to investigate the anti-bacterial effect of chlorine dioxide (ClO2) on extending thevase life of Gerbera jamesonii ‘Jenny’ which was first bredin Korea in 2012. Compared to commercialized biocides,ClO2 had been proved significantly effective for extendingthe vase life of cut gerbera flowers, equally with sodiumhypochlorite, silver nitrate, and 8-hydroxyquinoline sulfate.No bacteria were detected in the vase solutions treated withClO2 and these commercialized biocides on day 6 aftertreatment. But there were no significant differences on thevase life among the three ClO2 concentrations: 2, 5, and10μL•L−1. The ClO2 concentrations were rapidly decreasedon day 2 after treatment regardless of peduncle existence.Nevertheless, the antibacterial effect of ClO2 was main-tained up to day 6, indicating that the initial antibacterialeffect of ClO2 was a key factor for extending the vase life inthe gerbera flowers. The study results verified the antibacte-rial effect of ClO2 on prolonging the vase life of Gerberajamesonii ‘Jenny’ and demonstrated that appropriate ClO2application can prolong the postharvest life of cut gerberasvia its antimicrobial effect.