The antibacterial properties of Malaysian tualang honey against wound and enteric microorganisms in comparison to manuka honey

<p>Abstract</p> <p>Background</p> <p>Antibiotic resistance of bacteria is on the rise, thus the discovery of alternative therapeutic agents is urgently needed. Honey possesses therapeutic potential, including wound healing properties and antimicrobial activity. Although the antimicrobial activity of honey has been effectively established against an extensive spectrum of microorganisms, it differs depending on the type of honey. To date, no extensive studies of the antibacterial properties of tualang (<it>Koompassia excelsa</it>) honey on wound and enteric microorganisms have been conducted. The objectives of this study were to conduct such studies and to compare the antibacterial activity of tualang honey with that of manuka honey.</p> <p>Methods</p> <p>Using a broth dilution method, the antibacterial activity of tualang honey against 13 wound and enteric microorganisms was determined; manuka honey was used as the control. Different concentrations of honey [6.25-25% (w/v)] were tested against each type of microorganism. Briefly, two-fold dilutions of honey solutions were tested to determine the minimum inhibitory concentration (MIC) against each type of microorganism, followed by more assays within a narrower dilution range to obtain more precise MIC values. MICs were determined by both visual inspection and spectrophotometric assay at 620 nm. Minimum bactericidal concentration (MBC) also was determined by culturing on blood agar plates.</p> <p>Results</p> <p>By visual inspection, the MICs of tualang honey ranged from 8.75% to 25% compared to manuka honey (8.75-20%). Spectrophotometric readings of at least 95% inhibition yielded MIC values ranging between 10% and 25% for both types of honey. The lowest MBC for tualang honey was 20%, whereas that for manuka honey was 11.25% for the microorganisms tested. The lowest MIC value (8.75%) for both types of honey was against <it>Stenotrophomonas maltophilia</it>. Tualang honey had a lower MIC (11.25%) against <it>Acinetobacter baumannii </it>compared to manuka honey (12.5%).</p> <p>Conclusion</p> <p>Tualang honey exhibited variable activities against different microorganisms, but they were within the same range as those for manuka honey. This result suggests that tualang honey could potentially be used as an alternative therapeutic agent against certain microorganisms, particularly <it>A. baumannii </it>and <it>S. maltophilia</it>.</p

Medical-grade honey enriched with antimicrobial peptides has enhanced activity against antibiotic-resistant pathogens

Honey has potent activity against both antibiotic-sensitive and -resistant bacteria, and is an interesting agent for topical antimicrobial application to wounds. As honey is diluted by wound exudate, rapid bactericidal activity up to high dilution is a prerequisite for its successful application. We investigated the kinetics of the killing of antibiotic-resistant bacteria by RS honey, the source for the production of Revamil® medical-grade honey, and we aimed to enhance the rapid bactericidal activity of RS honey by enrichment with its endogenous compounds or the addition of antimicrobial peptides (AMPs). RS honey killed antibiotic-resistant isolates of Pseudomonas aeruginosa, Staphylococcus epidermidis, Enterococcus faecium, and Burkholderia cepacia within 2 h, but lacked such rapid activity against methicillin-resistant S. aureus (MRSA) and extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli. It was not feasible to enhance the rapid activity of RS honey by enrichment with endogenous compounds, but RS honey enriched with 75 μM of the synthetic peptide Bactericidal Peptide 2 (BP2) showed rapid bactericidal activity against all species tested, including MRSA and ESBL E. coli, at up to 10–20-fold dilution. RS honey enriched with BP2 rapidly killed all bacteria tested and had a broader spectrum of bactericidal activity than either BP2 or honey alone

Two Major Medicinal Honeys Have Different Mechanisms of Bactericidal Activity

Honey is increasingly valued for its antibacterial activity, but knowledge regarding the mechanism of action is still incomplete. We assessed the bactericidal activity and mechanism of action of Revamil® source (RS) honey and manuka honey, the sources of two major medical-grade honeys. RS honey killed Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa within 2 hours, whereas manuka honey had such rapid activity only against B. subtilis. After 24 hours of incubation, both honeys killed all tested bacteria, including methicillin-resistant Staphylococcus aureus, but manuka honey retained activity up to higher dilutions than RS honey. Bee defensin-1 and H2O2 were the major factors involved in rapid bactericidal activity of RS honey. These factors were absent in manuka honey, but this honey contained 44-fold higher concentrations of methylglyoxal than RS honey. Methylglyoxal was a major bactericidal factor in manuka honey, but after neutralization of this compound manuka honey retained bactericidal activity due to several unknown factors. RS and manuka honey have highly distinct compositions of bactericidal factors, resulting in large differences in bactericidal activity

New mediterranean biodiversity records (November, 2016)

This Collective Article presents information on 26 taxa belonging to 8 Phyla and extending from the western Mediterranean to the Levantine Sea. The new records were found in 9 countries as follows: Spain: first record for the Mediterranean of the crab Cancer bellianus; Algeria: further records of the alien fish Lagocephalus sceleratus in western Algerian waters; Italy: first report on the presence and establishment of the ctenophore Mnemiopsis leidyi in Lessina and Varano Lagoons (W. Adriatic) and of Penaeus aztecus in Corigliano Gulf (Italian Ionian). Moreover, the extension of the distribution range of the polychaete Branchiomma bairdi to W. Sicily as well as that of the crab Ocypode cursor and the bryozoan Catenicella paradoxa to E. Sicily are cited. Slovenia: the record of the rare saccoglossan gastropod Placida cremoniana from Piran (Gulf of Trieste) is the first for the Adriatic; Greece: the native sea slug Eubranchus farrani is the first from the Eastern Mediterranean; many sightings of the bamboo corals Isididae distributed along all the E. Ionian Sea and the establishment of P. aztecus in all Greek waters are also reported for first time; the westernmost extension of the alien urchin Diadema setosum in Cretan waters is cited and new sightings of the alien species Goniobranchus annulatus and Pterois miles are presented. Turkey: the alien fish Champsodon capensis is reported for first time from the Aegean Sea and the native acari Agauopsis microrhyncha from the Levantine Sea; a new observation of the alien crab Atergatis roseus in Güllük Bay-Aegean is also mentioned; Cyprus: first records of the alien urchin D. setosum and Lobotes surinamensis in Cypriot waters; Lebanon: several sightings of Monachus monachus from Lebanese waters indicate a potential better status for the species in the area; Egypt: first records of the alien crab Dorippe quadridens and the alien gastropods Nerita sanguinolenta and Conomurex persicus from the Mediterranean Egyptian waters; extension of the distribution range of Diodora funiculata and Diodora rueppellii and a second record of the alien Fulvia fragilis in the same area

Production and Testing of the LO and CLK Generation Module Built in MicroTCA.4 Form Factor

The local oscillator and clock generation module generates a low noise local oscillator out of the global reference that is distributed over the accelerator. The module is implemented such that it fits into the rear slots 15 and 14 of a standard MicroTCA.4 crate. In the contribution we present the manufacturing and testing process of 60 units that are being deployed in the European XFEL. Comparison between modules is performed based on the measured parameters

RTM RF Backplane for MicroTCA.4 Crates

We developed a new Rear Transition Module (RTM) Backplane for MicroTCA.4 crates that is compliant with the PICMG standard and an optional crate extension. The RTM Backplane provides multiple links for high-precision clock and RF signals to analog RTM cards. Usage of an RTM Backplane allows to significantly simplify the cable management, and therefore to increase the reliability of electronic controls when multiple analog RF front-ends are required. In addition, the RTM backplane allows also to add so called extended RTMs (eRTM) and RTM Power Modules (RTM-PM) to an 12 slot MicroTCA crate. Up to four 6 HE wide eRTMs and two RTM-PMs can be installed behind the front PM and MCH modules. An eRTM attached to the MCH via Zone 3 connector is used for analog signal management on the RTM backplane. This eRTM allows also installing a powerful CPU to extend the processing capacity of the MTCA.4 crate. Three additional eRTMs provide space for analog electronics for supplying signals to the uRTMs. The RTM-PMs deliver managed low-noise (separated from front crate PMs) analog bipolar power (+VV,-VV) for the RTMs and an unipolar power for the eRTMs. This extends functionality of the MicroTCA.4 crate and offers unique performance improvement for analog front-end electronics. This paper covers a new concept of the RTM Backplane, a new implementation for the real-time LLRF control system and performance evaluation of designed prototype

Drift Compensation Module for Pulsed or CW Machines at 1.3GHz, 3.0 GHz and 3.9 GHz

The drift compensation module uses an injected reference approach which is used to compensate for amplitude and phase drifts in thereceiver section induced by environmental changes. In the contribution we present the electrical and mechanical design flows for various frequencies and the two different modes of operation. During the design process we used several microwave modelling tools and the contribution summarizes the results. The evaluation results include long term measurements of one drift calibration module in a realistic environment. Special emphasis is put on the implementation of the mechanics of the module since it is tightly coupled to the final performance

An assessment of the transmission rate of four pospiviroid species through tomato seeds

Greenhouse experiments were conducted to investigate the importance of tomato seeds as a route of pospiviroid dissemination. More than 7000 seeds were collected from tomato plants mechanically inoculated with Tomato apical stunt viroid, Citrus exocortis viroid, Columnea latent viroid and Potato spindle tuber viroid. Fruits and part of the seeds were found to be 100 % infected by the inoculated pospiviroid by means of RT-PCR testing. Much of the rest of the seeds were sown and produced about 4700 seedlings. None of the seedlings were found positive for the respective pospiviroid. This shows that pospiviroid seed transmission in tomato is very rare

Present and Future Optical-to-Microwave Synchronization Systems at REGAE Facility for Electron Diffraction and Plasma Acceleration Experiments

Relativistic Electron Gun for Atomic Explorations (REGAE) is a Radio Frequency (RF) driven linear accelerator. It uses frequency tripled short photon pulses (~ 35 fs) from the Titanium Sapphire (Ti:Sa.) Laser system in order to generate electron bunches from the photo-cathode. The electron bunches are accelerated up to ~ 5 MeV kinetic energy and compressed down to sub-10 fs using the so called ballistic bunching technique. REGAE currently is used for electron diffraction experiments (by Prof. R.J.D. Miller's Group). In near future within the collaboration of Laboratory for Laser- and beam-driven plasma Acceleration (LAOLA), REGAE will also be employed to externally inject electron bunches into laser driven linear plasma waves. Both experiments require very precise synchronization (sub-50 fs) of the photo-injector laser and RF reference. In this paper we present experimental results of the current and new optical to microwave synchronization systems in comparison. We also address some of the issues related to the current system and give an upper limit in terms of its long-term performance