Aim: To determine that okra fruit extracts are effective in inhibiting growth and killing the Aggregatibacter actinomycetemcomitans (Aa) bacteria that cause aggressive periodontitis. Materials and ...Methods: Aa ATCC 4371 strain Y3 serotype b bacteria obtained from the Stock Research Center of the Faculty of Medicine, Airlangga University, Jawa Timur, Indonesia, were bred on the Mueller Hinton media with the inclusion criteria that identification of bacteria from the stock shows that the bacterium is Aa, and the growth of bacteria in the Mueller Hinton media is with a number of colonies between 30-300 colony forming units (CFU)/mL. Culture media containing Aa bacteria were incubated for 1 × 24h at 37°C, after it was diluted according to McFarland standard 0.5 (1.5 × 108 CFU/mL). Fresh okra fruit derived from Materia Medica was prepared for extract. Serial dilution or dilution methods of 1:2 (wt/vol) are used for the detection of minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). Results: One-way analysis of variance test showed a difference with significance (P = 0.000), whereas, Tukey honestly significant difference (HSD) test showed a significant difference between okra fruit extract group with positive control concentrations of 100%, 3.125%, and 1.565%. Conclusion: The okra fruit extract effectively kills the Aa bacteria that causes aggressive periodontitis, as indicated by MIC at a concentration of 3.125% and MBC at a concentration of 6.25%.
The parasite
Trypanasoma cruzi is responsible for Chagas disease and its triatomine vector,
Rhodnius prolixus, has a symbiotic relationship with the soil bacterium,
Rhodococcus rhodnii.
R. rhodnii ...that was previously genetically engineered to produce the anti-microbial peptide, cecropin A was co-infected with
T. cruzi into
R. prolixus resulting in clearance of the infectious
T. cruzi in 65% of the vectors. Similar anti-microbial peptides have been isolated elsewhere and were studied for differential toxicity against
T. cruzi and
R. rhodnii. Of the six anti-microbial peptides tested, apidaecin, magainin II, melittin, and cecropin A were deemed potential candidates for the Chagas paratransgenic system as they were capable of killing
T.
cruzi at concentrations that exhibit little or no toxic effects on
R. rhodnii. Subsequent treatments of
T. cruzi with these peptides in pair-wise combinations resulted in synergistic killing, indicating that improvement of the 65% parasite clearance seen in previous experiments may be possible utilizing combinations of different anti-microbial peptides.
Head-and-neck infection is one of the most frequently encountered issues in the field of oral and maxillofacial surgery. Most of the cases with head-and-neck infections are managed by empirical ...antibiotic therapy and extraction of offending infected tooth/teeth. However, long-term systemic antibiotic therapy can have profound compromising effects on host immune defense and thereby hamper healing, which, in turn, may lead to life-threatening complications such as localized septic foci or widespread septicemia at times leading to death of an individual. In this study, we are reviewing management of 15 cases with space infection in the maxillofacial region by local drug delivery with the help of collagen particles combined with mupirocin 2% w/w and metronidazole 1% w/w (BioFil-AB). We intend to study its efficacy in managing the space infections associated with extraoral infected wound as well as in preventing hazards of long-term systemic antibiotic therapy.
The aim of this study is to assess the efficacy of the topical use of BioFil-AB in infected maxillofacial wounds.
A total of 15 patients with infected maxillofacial wounds reporting to the department of oral and maxillofacial surgery were categorized into three groups depending on the severity of infections. Of these 15 cases, 8 patients were suffering from infected extraoral wounds, 3 had traumatic infection, and remaining 4 had extraoral consolidated abscesses due to odontogenic infection. All patients had a history of prior antibiotic therapy. Incision and drainage of the septic focus/foci were performed in most of the cases, and healing of the site was assessed after application of topical BioFil-AB (mupirocin + metronidazole + collagen granules) dressing.
Dressing with BioFil-AB granules proved to be efficient in control of infection as well as in promoting uneventful wound healing, especially with good follow-up. Further studies with a large sample size may be necessary to corroborate the findings and provide substantial evidence. This novel local drug delivery therapy will definitely help in maintenance of good host immune response as well as in preventing or minimizing occurrence of antibiotic resistance.
Peritonitis is a disease caused by bacterial strains that have become increasingly resistant to many antibiotics. The development of alternative therapeutic compounds is the focus of extensive ...research, so novel nanoparticles (NPs) with activity against antibiotic-resistant bacteria should be developed. In this study, the antibacterial activity of quaternary ammonium polyethyleneimine (QA-PEI) NPs was evaluated against Streptococcus viridans, Stenotrophomonas maltophilia and Escherichia coli. To appraise the antibacterial activity, minimal inhibitory concentration (MIC), minimal bactericidal concentration and bactericidal assays were utilised with different concentrations (1.56–100 µg/ml) of QA-PEI NPs. Moreover, 3-4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT) and annexin V/propidium iodide toxicity assays were performed in cell cultures. MICs for S. maltophilia and E. coli isolates were 12.5 and 25 µg/ml, respectively, whereas the MIC for S. viridans was 100 µg/ml. Furthermore, the growth curve assays revealed that these QA-PEI NPs at a concentration of 12.5 µg/ml significantly inhibited bacterial growth for the bacterial isolates studied. On the other hand, QA-PEI NPs lacked significant toxicity for cells when used at concentrations up to 50 μg/ml for 48 h. The present findings reveal the potential therapeutic value of this QA-PEI NPs as alternative antibacterial agents for peritonitis, especially against Gram-negative bacteria.
The solid-phase synthesis of a 738,192 member pyrrolidine bis-cyclic guanidine chemical library with four positions of diversity (R
1–R
4) is reported. Screening this library yielded eight compound ...mixtures with bactericidal activity against methicillin-resistant
Staphylococcus aureus. Thirty-six individual compounds from these mixtures exhibited potent bactericidal activity against important human pathogens.
The rapid rise in antibiotic-resistant Gram-positive bacterial infections prompted us to explore the development of novel strategies for synthesis of large chemical libraries amenable to high-throughput screening for antimicrobial activities. Here we report the solid-phase synthesis of a 738,192 member pyrrolidine bis-cyclic guanidine chemical library with 26 different amino acids at three positions of diversity and 42 carboxylic acids at the fourth position. This synthetic combinatorial library was developed for positional scanning and screened for bacteriostatic and bactericidal activities against the important human pathogen methicillin-resistant
Staphylococcus aureus (MRSA). The eight compound mixtures exhibiting bactericidal activity (10
μg/mL) against MRSA were used to direct the synthesis of 36 individual compounds that were then screened for activity against MRSA, vancomycin-resistant
Enterococcus faecalis (VRE), and two Gram-negative bacterial species. At least 20 individual compounds were bactericidal for MRSA at ⩽2.5
μg/mL, with a subset of these compounds showing bactericidal activities (⩽10
μg/mL) against the other species tested. This approach demonstrates the capability to synthesize and screen a complex library to yield promising antimicrobials that address a critical need for novel infectious disease therapeutics.
Reduction or elimination of chemically synthesized additives from foods is a current demand in food industry. A new approach to prevent the proliferation of microorganisms or protect food from ...oxidation is the use of essential oils or plant extracts as natural additives in foods. We have studied antimicrobial activity of rosemary extracts (Rosmarinus officinalis L.) against different species of Listeria and against different strains of L. monocytogenes. We used two extracts of rosemary, VivOX 20 and VivOX 40 (Vitiva d.d., Slovenia) containing different levels of carnosic acid. We wanted to proof an antimicrobial activity of selected rosemary extracts with two most commonly used methods: disc diffusion method and broth dilution method. With the disc diffusion method we have obtained the inhibition zone and at the lowest concentrations, where no visible bacterial growth was recorded, were assumed as minimal inhibitory concentration values (MIC). We determined MIC values in the ranges from 625 μg extract/ml EtOH to 5000 μg extract/ml EtOH for VivOX 20 and from 312.5 μg extract/ml EtOH do 2500 μg extract/ml EtOH for VivOX 40 in the medium. We have established that the resistance of Listeria species against rosemary extracts depends on: selected extract, selected concentration, various species and strain of Listeria. With broth dilution method we have determined minimal bactericidal concentration (MBC), as the concentration giving 0.1% bacterial survival. With this method we have tested two strains of L. monocytogenes and in determinate MBC values in the range from 15.63 μg/ml TSB to 98.5 μg/ml TSB for both tested extracts. Results have confirmed our assumption that resistance of Listeria against rosemary extracts depended on the selected strain.
Zahteve potrošnikov po celem svetu so zmanjšati oz. izločiti kemično sintetizirane konzervanse iz živil. Novejše metode preprečevanja mikrobne kontaminacije in oksidacije uporabljajo eterična olja ali rastlinske ekstrakte kot naravne konzervanse. Proučevali smo protimikrobno delovanje ekstraktov rožmarina (Rosmarinus officinalis L.) na različne vrste bakterij rodu Listeria in seve bakterij L. monocytogenes. Uporabili smo dva različna komercialno pripravljena ekstrakta rožmarina, VivOX 20 in VivOX 40 (Vitiva d.d., Slovenija), ki sta vsebovala različno koncentracijo karnozolne kisline. Protimikrobni učinek izbranih ekstraktov smo želeli dokazati z dvema najpogosteje uporabljenima metodama: metoda difuzije v trdnem gojišču in metoda razredčevanja v tekočem gojišču. Pri metodi difuzije v trdnem gojišču smo po inkubaciji odčitali nastale inhibicijske cone, s katerimi smo določili minimalne inhibitorne koncentracije (MIC), kot tiste koncentracije, pri katerih ni bilo vidne rasti bakterij na gojišču. Vrednosti MIC smo določili v območju med 625 μg ekstrakta/ml EtOH do 5000 μg ekstrakta/ml EtOH za ekstrakt VivOX 20 in med 312,5 μg ekstrakta/ml EtOH do 2500 μg ekstrakta/ml EtOH za ekstrakt VivOX 40. Ugotovili smo, da je odpornost listerij proti ekstraktoma rožmarina odvisna od izbranega ekstrakta, izbrane koncentracije ter vrste in seva listerij. Z metodo razredčevanja v tekočem gojišču smo določali minimalne baktericidne koncentracije (MBC), kot tiste koncentracije, pri katerih preživi 0,1 % testnih bakterij. Uporabili smo dva različna seva bakterij vrste L. monocytogenes in vrednosti MBC v večini poskusov določili med 15,63 μg/ml gojišča TSB in 98,5 μg/ml gojišča za oba uporabljena ekstrakta. Rezultati so ponovno potrdili našo domnevo, da je odpornost listerij proti ekstraktoma rožmarina odvisna od seva.
Harungana madagascariensis is well known for its topical antibacterial properties used in the elaboration of a lot of skin hygiene products. The aim of this study was, on the one hand, to evaluate ...the in vitro antibacterial activities of aqueous, ethanolic and ethyl acetate crude extracts of
Harungana madagascariensis leaves against bacterial strains representative of skin microflora and, on the other hand, to determine the chemical structure of the active compound. Only the ethyl acetate leaf extract presented important antibacterial activity. Its fractionation was carried out by column chromatography using silica gel 60 and it yielded 11 fractions. A bioautographic method, revealed in these fractions the presence of a flavanone as the active compound astilbin or 3-
O-α-
l-rhamnoside-5,7,3′,4′-tetrahydroxydihydroflavonol which was identified on the basis of its spectroscopic data. Concerning the antibacterial activity against the representative skin microflora of the armpit and feet, MIC and MBC ranged from 25 to 250 and 100 to 750
μg
ml
−1, respectively. The results showed that some bacteria considered to be responsible for bad odours at the armpit and feet levels, were destroyed at 200
μg
ml
−1 (MBC), a concentration sparing most of the useful saprophytic microflora. The minimal inhibitory quantity (MIQs) of astilbin ranged from 50 to 100
μg.
Outbreaks of infectious diseases have caused huge losses in the fish culture industry. The production of antimicrobial peptides has been identified as a major defense mechanism against infections. A ...cDNA encoding an antimicrobial peptide was isolated from the leukocyte cDNA library of orange-spotted grouper,
Epinephelus coioides. The predicted 67-amino acid prepropeptide, named epinecidin-1, consists of three domains: a signal peptide of 22 amino acids, a mature peptide of 25 amino acids, and a carboxy-terminal prodomain of 20 amino acids. The epinecidin-1 gene consisted of three introns and four exons. A TATA box and several consensus-binding motifs for transcription factors were found in the proximal region 5′ to the transcription initiation site. A synthetic, amidated mature peptide of epinecidin-1 exhibited high antimicrobial activity against
Vibrio parahaemolyticus,
Vibrio alginolyticus,
Vibrio vulnificus,
Pasturella multocida,
Morganella morganii,
Aeromonas sobrio,
Aeromonas hydrophila,
Flavobacterium meningosepticum and
Escherichia coli DH5α (minimal bactericidal concentration (MBC)
<
5 μM). Most of these bacteria are known pathogens in aquaculture. Some fungi, such as
Candida albicans and
Microsporosis sanis, were also sensitive to this synthetic peptide (MBC
<
20 μM). In conclusion, epinecidin-1 may be effective in the treatment or prevention of bacterial infections in aquaculture, and it may be a candidate gene for the generation of transgenic fish to improve disease resistance in aquaculture.
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