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Antimicrobial Effects (antimicrobial + effects)
Selected AbstractsAntimicrobial Effects of Lactoferrin, Lysozyme, and the Lactoperoxidase System and Edible Whey Protein Films Incorporating the Lactoperoxidase System Against Salmonella enterica and Escherichia coli O157:H7JOURNAL OF FOOD SCIENCE, Issue 7 2005Seacheol Min ABSTRACT: Lactoferrin (LF), lysozyme (LZ), the lactoperoxidase system (LPOS), and edible whey protein isolate (WPI) films incorporating LPOS were studied for inhibition of Salmonella enterica and Escherichia coli O157:H7. Antimicrobial effects of LF (5 to 40 mg/mL), LZ (1 to 20 mg/mL), and LPOS (0.5% to 5.0% [w/v] [0.03,.25 g/g, dry basis]) were examined by measuring turbidity of antimicrobial-containing media after inoculation and by examining cell inhibition by WPI films incorporating LPOS (LPOS-WPI films) on an agar recovery medium. Elastic modulus (EM), tensile strength (TS), percent elongation (%E), oxygen permeability (OP), and Hunter L, a and b of WPI films incorporating 0.03 to 0.25 g/g of LPOS were compared with those of plain WPI films without LPOS. The growth of S. enterica and E. coli O157:H7 (4 log colony-forming units [CFU]/mL) in tryptic soy broth (TSB) was not prevented by LF at ,20 and ,40 mg/mL, respectively. S. enterica and E. coli O157:H7 in TSB were not inhibited by LZ at , 6 and , 20 mg/mL, respectively. LPOS at concentrations of 2.75% (w/v) and 1.0% (w/v) reduced S. enterica and E. coli O157:H7 to below the limit of detection (1 CFU/mL) in TSB, respectively. LPOS-WPI films (0.15 g/g) completely inhibited S. enterica and E. coli O157:H7 (4 log CFU/cm2), inoculated either onto agar before placing the film disc or onto top of the film disc. Incorporation of 0.25 g/g of LPOS decreased EM, TS, and %E. The oxygen barrier property of WPI films was improved with the incorporation of LPOS at 0.15 to 0.25 g/g. [source] Antimicrobial Effects of Wine on Escherichia coli O157:H7 and Salmonella typhimurium in a Model Stomach SystemJOURNAL OF FOOD SCIENCE, Issue 1 2003J.R. Just ABSTRACT: Survival of Escherichia coli O157:H7 and Salmonella spp. was evaluated in grape juice and wine. Bacteria were inactivated in wine within 60 min but survived up to 16 d in juice. A model stomach system containing food and synthetic gastric fluid (SGF) was designed to investigate the antibacterial effect of wine when consumed with a meal. In this system, wine had little effect on E. coli O157:H7 survival whereas Salmonella was undetectable after 120 min. A nonvolatile wine fraction (containing acids) was more effective in killing Salmonella than a volatile wine fraction (containing alcohol), suggesting that antibacterial activity of wine is primarily acid dependent. [source] Antimicrobial Effects of Lactoferrin, Lysozyme, and the Lactoperoxidase System and Edible Whey Protein Films Incorporating the Lactoperoxidase System Against Salmonella enterica and Escherichia coli O157:H7JOURNAL OF FOOD SCIENCE, Issue 7 2005Seacheol Min ABSTRACT: Lactoferrin (LF), lysozyme (LZ), the lactoperoxidase system (LPOS), and edible whey protein isolate (WPI) films incorporating LPOS were studied for inhibition of Salmonella enterica and Escherichia coli O157:H7. Antimicrobial effects of LF (5 to 40 mg/mL), LZ (1 to 20 mg/mL), and LPOS (0.5% to 5.0% [w/v] [0.03,.25 g/g, dry basis]) were examined by measuring turbidity of antimicrobial-containing media after inoculation and by examining cell inhibition by WPI films incorporating LPOS (LPOS-WPI films) on an agar recovery medium. Elastic modulus (EM), tensile strength (TS), percent elongation (%E), oxygen permeability (OP), and Hunter L, a and b of WPI films incorporating 0.03 to 0.25 g/g of LPOS were compared with those of plain WPI films without LPOS. The growth of S. enterica and E. coli O157:H7 (4 log colony-forming units [CFU]/mL) in tryptic soy broth (TSB) was not prevented by LF at ,20 and ,40 mg/mL, respectively. S. enterica and E. coli O157:H7 in TSB were not inhibited by LZ at , 6 and , 20 mg/mL, respectively. LPOS at concentrations of 2.75% (w/v) and 1.0% (w/v) reduced S. enterica and E. coli O157:H7 to below the limit of detection (1 CFU/mL) in TSB, respectively. LPOS-WPI films (0.15 g/g) completely inhibited S. enterica and E. coli O157:H7 (4 log CFU/cm2), inoculated either onto agar before placing the film disc or onto top of the film disc. Incorporation of 0.25 g/g of LPOS decreased EM, TS, and %E. The oxygen barrier property of WPI films was improved with the incorporation of LPOS at 0.15 to 0.25 g/g. [source] Antimicrobial effects of mechanical debridementPERIODONTOLOGY 2000, Issue 1 2002GREGOR J. PETERSILKA First page of article [source] Influence of dentin on pH of 2% chlorhexidine gel and calcium hydroxide alone or in combinationDENTAL TRAUMATOLOGY, Issue 3 2010Laila Gonzales Freire Most of the times, these objectives are not achieved solely by chemomechanical preparation, and intracanal dressing may be necessary. In these cases, calcium hydroxide is used as a root canal dressing due to its well-known and recognized antimicrobial activity. Chlorhexidine has a wide spectrum of antimicrobial activity and its association with calcium hydroxide has been recommended in an attempt to amplify antimicrobial effects of calcium hydroxide. It is also known that dentin exerts a buffering effect under wide pH variations, and may be responsible for decreasing the antimicrobial activity of drugs inside the root canal. The objectives of this study were to assess the pH of 2% chlorhexidine gel and calcium hydroxide alone or in combination, as well as the influence of dentin on the pH of these compounds. Dentin powder was obtained from bovine teeth and added as 1.8% to the volume of the medications. All substances were individually stored in plastic flasks, in triplicate. A pH meter was used at five different moments to assess pH in viscous medium: immediately after preparation and after 24 h, and 7, 14, and 21 days. Results were analyzed by paired Student's t -test. Statistically significant differences were observed in the 2% chlorhexidine gel group alone or associated with calcium hydroxide and added of dentin powder (P < 0.05). Mean pH values indicated the influence of dentin powder because of a significant increase in pH. Calcium hydroxide with propylene glycol as the vehicle always showed high pH, demonstrating that this compound was not affected by the presence of dentin. [source] Effect of ozone on oral cells compared with established antimicrobialsEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 5 2006Karin C. Huth Ozone has been proposed as an alternative antiseptic agent in dentistry based on reports of its antimicrobial effects in both gaseous and aqueous forms. This study investigated whether gaseous ozone (4 × 106 µg m,3) and aqueous ozone (1.25,20 µg ml,1) exert any cytotoxic effects on human oral epithelial (BHY) cells and gingival fibroblast (HGF-1) cells compared with established antiseptics [chlorhexidine digluconate (CHX) 2%, 0.2%; sodium hypochlorite (NaOCl) 5.25%, 2.25%; hydrogen peroxide (H2O2) 3%], over a time of 1 min, and compared with the antibiotic, metronidazole, over 24 h. Cell counts, metabolic activity, Sp-1 binding, actin levels, and apoptosis were evaluated. Ozone gas was found to have toxic effects on both cell types. Essentially no cytotoxic signs were observed for aqueous ozone. CHX (2%, 0.2%) was highly toxic to BHY cells, and slightly (2%) and non-toxic (0.2%) to HGF-1 cells. NaOCl and H2O2 resulted in markedly reduced cell viability (BHY, HGF-1), whereas metronidazole displayed mild toxicity only to BHY cells. Taken together, aqueous ozone revealed the highest level of biocompatibility of the tested antiseptics. [source] Comparative study on the antimicrobial activities of different sandalwood essential oils of various originFLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2006Leopold Jirovetz Abstract In total, eight samples of different sandalwoods [Amyris balsamifera L., Santalum album L. and Santalum spicatum (R.Br.) A.DC.] and a mixture of , - and , -santalols, as well as eugenol as reference compound, were tested by an agar dilution and agar diffusion method for their antimicrobial activities against the yeast Candida albicans, the Gram-positive bacterium Staphylococcus aureus and the Gram-negative bacteria Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae. The main compounds of each essential oil were investigated by gas chromatographic,spectroscopic (GC-FID and GC,MS) and ,olfactory methods to obtain information about the inßuence of these volatiles on the observed antimicrobial effects. For the santalol mixture, as well as for one S. album and one S. spicatum sample with moderate concentrations of santalols, antimicrobial activity was found against all the strains used. The A. balsamifera sample, containing only a small quantity of , -santalol and nearly no , -santalol, showed high effects only against Klebsiella pneumoniae, while against the other strains weak or no activity was observed. Therefore, santalols in medium and/or high concentrations in sandalwood oils show a significant inßuence on antimicrobial potential in such natural products. Copyright © 2006 John Wiley & Sons, Ltd. [source] Effects of extracts of miswak and derum on proliferation of Balb/C 3T3 fibroblasts and viability of cariogenic bacteriaINTERNATIONAL JOURNAL OF DENTAL HYGIENE, Issue 2 2006H Darmani Abstract:,Objectives:,This study examined the effects of extracts of two chewing sticks on proliferation of fibroblasts and viability of cariogenic bacteria. Methods:,Aqueous extracts of miswak (Salvadora persica; Arak tree) and derum (Juglans regia; walnut tree) were prepared and their effects investigated on growth of Balb/C 3T3 mouse fibroblasts by measuring the mitochondrial succinic dehydrogenase activity. Furthermore, the effects on the viability of various cariogenic bacteria (Streptococcus mutans, Streptococcus salivarius, Lactobacillus casei and Actinomyces viscosus) was also determined. Results:,The data revealed that Balb/C 3T3 fibroblasts exposed to aqueous extracts of miswak or derum showed an increase in cell proliferation by 156% and 255%, respectively, in comparison with controls (p<0.0001). Furthermore, extracts from both miswak and derum had adverse effects on the growth of the cariogenic microorganisms, with derum having significantly greater antimicrobial effects than miswak and at much lower concentrations against all the bacteria tested. The most sensitive organisms were A. viscosus, followed by S. mutans, S. salivarius, with L. casei being the most resistant. Conclusion:,The results show that aqueous extracts of miswak and derum enhance the growth of fibroblasts and inhibit the growth of cariogenic bacteria, with the derum extract showing greater activity than miswak. [source] Evaluation of pre-heating and extraction solvents in antioxidant and antimicrobial activities of garlic, and their application in fresh pork pattiesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 2 2010Sung Y. Park Summary The objectives of this study were to screen the optimum conditions for antioxidant and antimicrobial activities of garlic as affected by pre-heating and different extraction solvents, and to evaluate the antioxidant and antimicrobial effects of these extracts in ground meat during refrigerated storage. Methanol extracted garlic had a greater total phenolic content, 1,1-diphenyl-2-picrylhydrazyl (DPPH)-radical scavenging activity and reducing power than water extracted one (P < 0.05), whereas the latter had a greater yield and iron chelating ability than the former (P < 0.05). Moreover, water extract from fresh garlic (WEFG) and methanol extract from heated garlic (MEHG) produced an inhibition zone against Escherichia coli O157:H7 and Listeria monocytogenes. The addition of garlic extracts (WEFG, MEHG and their combinations WEFMEHG)) to pork patties decreased the pH, hunter a values (redness), thiobarbituric acid substances values and the number of total plate count and Enterobacteriaceae (P < 0.05), while the hunter b values (yellowness) increased (P < 0.05). Results of this study indicated that the use of the garlic extracts was able to control lipid oxidation and microbial growth in pork patties. [source] A novel in vitro flat-bed perfusion biofilm model for determining the potential antimicrobial efficacy of topical wound treatmentsJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2009R.M.S. Thorn Abstract Aims:, To develop an in vitro flat-bed perfusion biofilm model that could be used to determine the antimicrobial efficacy of topically applied treatments. Methods and Results:,Pseudomonas aeruginosa and Staphylococcus aureus biofilms were grown within continuously perfused cellulose matrices. Enumeration of the biofilm density and eluate was performed at various sampling times, enabling determination of the biofilm growth rate. Two antimicrobial wound dressings were applied to the surface of mature biofilms and periodically sampled. To enable real-time imaging of biofilm growth and potential antimicrobial kinetics, a bioluminescent Ps. aeruginosa biofilm was monitored using low-light photometry. Target species produced reproducible steady-state biofilms at a density of c. 107 per biofilm support matrix, after 24-h perfusion. Test dressings elicited significant antimicrobial effects, producing differing kill kinetic profiles. There was a good correlation between photon and viable count data. Conclusions:, The model enables determination of the antimicrobial profile of topically applied treatments against target species biofilms, accurately differentiating bactericidal from bacteriostatic effects. Moreover, these effects could be monitored in real time using bioluminescence. Significance and Impact of the Study:, This is the first in vitro biofilm model which can assess the antimicrobial potential of topical therapies in a dynamic growth environment. [source] Electrospun PEG,PLA nanofibrous membrane for sustained release of hydrophilic antibioticsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2010Xiuling Xu Abstract Reported in this study is the successful incorporation of a hydrophilic antibiotic drug, tetracycline hydrochloride (TCH), into electrospun PEG,PLA nanofibrous membrane without loss of its bioactivity. Degradation behavior of the copolymer was studied in vitro. Release behavior of TCH from the electrospun membrane and antimicrobial effects of the TCH-loaded membrane against Staphylococcus aureus culture were investigated. The medicated nanofibrous membrane demonstrated sustained release of TCH over 6 days and was found to be effective in inhibiting growth of S. aureus. In addition, increasing the antibiotic drug content in the electrospun membranes was found to enhance the anti-bacterial effectiveness of the medicated fiber mats. And the combination of mechanical barriers provided by the electrospun biodegradable nanofibrous membranes and their capability of local sustained delivery of antibiotics made these membranes more useful in biomedical applications, particularly as new wound dressings for ulcers caused by diabetes or other diseases, and to provide a better means of treatment for these malignant wounds and ulcers. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] A method to study sustained antimicrobial activity of rinse and dentifrice components on biofilm viability in vivoJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2006H. C. Van Der Mei Abstract Aim: To develop an improved method for quantitative assessment of antimicrobial efficacy and substantivity of mouth rinses and dentifrices on in vivo treated plaque. Material and Methods: Nine- and 72-h-old plaques were formed in volunteers carrying out standardized hygiene using NaF-containing dentifrice. Plaques were collected before (baseline) in vivo treatment with dentifrices or chlorhexidine mouth rinse, immediately post-treatment and after 1 or 6 h, dispersed in demineralized water and stained with live/dead stain after which bacteria were enumerated. Dispersed baseline plaques were treated with dentifrices or chlorhexidine to determine antimicrobial efficacy against planktonic bacteria. Results: Baseline plaques revealed 56,41% viable organisms in 9- and 72-h-old plaques, respectively. Treatment of planktonic (dispersed baseline plaque) bacteria resulted in 1,4% viable organisms. Chlorhexidine mouth rinse and dentifrices produced strong immediate antimicrobial effects, but after 1 or 6 h, the proportion of viable organisms in 9-h-old plaques rebounded significantly with only chlorhexidine mouth rinse retaining significant efficacy. Seventy-two-hour-old plaques were less susceptible to antimicrobials, although dentifrices appeared more effective after 6 h than initially, whereas efficacy of chlorhexidine rinse continued to drop with time post-treatment. Conclusions: The proposed method holds promise for assessment of both immediate and retained antimicrobial actions of oral treatments against dental plaque in vivo. [source] Recent concepts in plaque formationJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 2003J.-P. Bernimoulin Abstract Dental plaque is an adherent, bacterial film, and is the main pathological agent for periodontal diseases. The formation of dental plaque can occur both supragingivally and subgingivally. The development of plaque is a three-step process. Following the formation of a pellicle, pioneer micro-organisms will adhere to it, proliferate and form colonies. The final stage involves the aggregation of filamentous organisms and spirochetes into a cohesive biofilm. Many products of the plaque bacteria reach the subepithelial tissue, causing inflammatory responses such as increased vascularity and leukocyte diapedesis. Both supragingival and subgingival plaque may form a hard, mineralized mass called calculus. The surface of calculus harbours bacteria, which may exacerbate the inflammatory responses. An effective oral antiseptic must be active against a wide range of Gram-positive and Gram-negative bacterial species, including streptococci and fusobacteria. Ideally, an effective agent would also penetrate the plaque biofilm. Data show that essential oil and chlorhexidine mouthwashes have the broadest antimicrobial effects. [source] Anti-aging properties of resveratrol: review and report of a potent new antioxidant skin care formulationJOURNAL OF COSMETIC DERMATOLOGY, Issue 1 2008Richard A Baxter MD Summary Resveratrol, an antioxidant polyphenol from red wine, has been the subject of intense interest in recent years due to a range of unique anti-aging properties. These include cardiovascular benefits via increased nitric oxide production, down-regulation of vasoactive peptides, lowered levels of oxidized low-density lipoprotein, and cyclooxygenase inhibition; possible benefits on Alzheimer's disease by breakdown of beta-amyloid and direct effects on neural tissues; phytohormonal actions; anticancer properties via modulation of signal transduction, which translates into anti-initiation, antipromotion, and antiprogression effects; antimicrobial effects; and sirtuin activation, which is believed to be involved in the caloric restriction-longevity effect. Here we report a resveratrol-based skin care formulation, with 17 times greater antioxidant activity than idebenone. The role of resveratrol in prevention of photoaging is reviewed and compared with other antioxidants used in skin care products. [source] Synthesis and structure,activity relationship of ,-defensins, multi-functional peptides of the immune systemJOURNAL OF PEPTIDE SCIENCE, Issue 4 2006Enno Klüver Abstract ,-defensins are a large family of multiple disulfide-bonded peptides occurring in mammals and birds. They play an important role in the innate immune system, directly killing microbial organisms. Recent research has demonstrated that ,-defensins are important for other biological functions beyond antimicrobial effects, including inhibition of viral infection, interaction with Toll-like receptors, chemotactic effects, and sperm function. The corresponding broad spectrum of activities makes this peptide class an important subject and tool in immunologic research. In this review, we summarize the current status of the routes to obtain synthetic ,-defensins, their major structural properties and structure,activity relationship. Copyright © 2006 European Peptide Society and John Wiley & Sons, Ltd. [source] Antimicrobial and cytotoxic activities of Malaysian endophytesPHYTOTHERAPY RESEARCH, Issue 5 2010Kalavathy Ramasamy Abstract Endophytes, which are receiving increasing attention, have been found to be potential sources of bioactive metabolites following the discovery of paclitaxel producing endophytic fungi. In the present study, a total of 348 endophytes were isolated from different parts of 24 Malaysian medicinal plants. Three selected endophytes (HAB10R12, HAB11R3 and HAB21F25) were investigated for their antimicrobial and cytotoxic activities. For antimicrobial activity, HAB10R12 and HAB11R3 were found to be most active against bacteria and fungi, respectively. Their antimicrobial effects were comparable to, if not better than, a number of current commercial antibacterial and antifungal agents. Both HAB10R12 and HAB21F25 were found to be potential anticancer drug candidates, having potent activity against MCF-7 and HCT116 cell lines and warrant further investigation. Copyright © 2009 John Wiley & Sons, Ltd. [source] Antimicrobial activity of clove and rosemary essential oils alone and in combinationPHYTOTHERAPY RESEARCH, Issue 10 2007YuJie Fu Abstract In the present study, the antimicrobial activity of the essential oils from clove (Syzygium aromaticum (L.) Merr. et Perry) and rosemary (Rosmarinus officinalis L.) was tested alone and in combination. The compositions of the oils were analysed by GC/MS. Minimum inhibitory concentrations (MIC) against three Gram-positive bacteria, three Gram-negative bacteria and two fungi were determined for the essential oils and their mixtures. Furthermore, time-kill dynamic processes of clove and rosemary essential oils against Staphylococcus epidermidis, Escherichia coli and Candida albicans were tested. Both essential oils possessed significant antimicrobial effects against all microorganisms tested. The MICs of clove oil ranged from 0.062% to 0.500% (v/v), while the MICs of rosemary oil ranged from 0.125% to 1.000% (v/v). The antimicrobial activity of combinations of the two essential oils indicated their additive, synergistic or antagonistic effects against individual microorganism tests. The time-kill curves of clove and rosemary essential oils towards three strains showed clearly bactericidal and fungicidal processes of 1/2 × MIC, MIC, MBC and 2 × MIC. Copyright © 2007 John Wiley & Sons, Ltd. [source] Black teeth: beauty or caries prevention?COMMUNITY DENTISTRY AND ORAL EPIDEMIOLOGY, Issue 2 2006Practice, beliefs of the Kammu people Abstract , Background:, To be beautiful and caries-free, Kammu women in Laos and Vietnam habitually paint their teeth black. Although this practice existed for many generations, it is now known only among the elderly. Objectives:, To describe how the tooth-blackening procedure is performed and to test the black stain for possible antimicrobial effects in laboratory experiments. Methods:, Information on how to blacken teeth was obtained by interviewing groups of elderly Kammu people living in different villages in Laos and Vietnam. Water extracts of the stain were placed in wells in agar plates and the plates incubated with Streptococcus mutans or S. sobrinus. The stain was also let such that it covered half of the strip test-side of the Dentocult SM® Strip Mutans test kit and incubated with saliva from five persons known to carry mutans streptococci in their saliva. Results:, Interviews revealed that three plants were commonly used: Dracontomelon dao nuts (DD nuts), Cratoxylum formosum (CF) wood or Croton cascarilloides (CC) wood. The parts (nut, wood) were burned and soot collected on metal plates. The fresh soot, which had a viscous consistency, was applied to teeth with the index finger. Extracts of soot of the DD nuts had no effect on the streptococci on agar plates but inhibited the growth of salivary mutans streptococci on strips. Controls using soot from birch tree (Betula pendula) had no effect. Conclusions:, The procedure was simple and resulted in black, beautiful (?) teeth. The soot of DD nuts effectively inhibited growth of salivary mutans streptococci in in vitro experiments. [source] | |||||||||||||