Inhibition Of Bacterial Growth Research Articles

Biocidal effects of organometallic materials supported on ZSM-5 Zeolite: Influence of the physicochemical and surface properties

Antifouling coatings containing biocidal agents can be used to prevent the accumulation of biotic deposits on submerged surfaces; however, several commercial biocides can negatively affect the ecosystem. In this study, various formulations of a potential biocide product comprising copper nanoparticles and capsaicin supported on zeolite ZSM-5 were analyzed to determine the influence of the concentration of each component. The incorporation of copper was evidenced by scanning electron microscopy and energy dispersive spectroscopy. Similarly, Fourier-transform infrared spectroscopy confirmed that capsaicin was supported on the zeolite surface. The presence of capsaicin on the external zeolite surface significantly reduced the surface area of the zeolite. Finally, bacterial growth inhibition analysis showed that copper nanoparticles inhibited the growth of strains Idiomarina loihiensis UCO25, Pseudoalteromonas sp. UCO92, and Halomonas boliviensis UCO24 while the organic component acted as a reinforcing biocide.

Surface Charge-Switchable Antifouling Block Copolymer with Bacteriostatic Properties.

Zwitterionic polymers are an emerging family of effective, low-fouling materials that can withstand unintended interactions with biological systems while exhibiting enhanced activity in bacterial matrix deterioration and biofilm eradication. Herein, we modularly synthesized an amphiphilic block copolymer, ZABCP, featuring potential bacteriostatic properties composed of a charge-switchable polyzwitterionic segment and a redox-sensitive pendant disulfide-labeled polymethacrylate block. The leucine-appended polyzwitterionic segment with alternatively positioned cationic amine and anionic carboxylate functionalities undergoes charge alterations (+ve → 0 → -ve) on pH variation. By introducing appropriate amphiphilicity, ZABCP forms distinct vesicles with redox-sensitive bilayer membranes and zwitterionic shielding coronas, enabling switching of surface charge. ZABCP vesicles exhibit 180 ± 20 nm hydrodynamic diameter, and its charge switching behavior in response to pH was confirmed by the change of zeta potential value from -23 to +36 mV. The binding interaction between ZABCP vesicles with lysozyme and pepsin proteins strengthens when the surface charge shifts from neutral (pH 7.4) to either anionic or cationic. This surface-charge-switchable phenomenon paves the way for implementing cationic ZABCP vesicles for bacterial cell growth inhibition, which is shown by the pronounced transition of cellular morphology, including clustering, aggregation, or elongation as well as membrane disruption for both Bacillus subtilis (Gram-positive) and Escherichia coli (Gram-negative). Such enhanced bacteriostatic activity could be ascribed to a strong electrostatic interaction between cationic vesicles and negatively charged bacterial membranes, leading to cell membrane disruption. Overall, this study provides a tailor-made approach to adopt low-fouling properties and potential bacteriostatic activity using zwitterionic polymers through precise control of pH.

Optimizing bacterial growth inhibition in spring water through central composite design using a nanocomposite of nanocellulose and green-synthesized nanosilver

Optimizing bacterial growth inhibition in spring water through central composite design using a nanocomposite of nanocellulose and green-synthesized nanosilver

Resistance of a mixed bacterial culture isolated from bee dysbiosis to disinfectant in laboratory conditions

Disinfection is one of the components of preventive actions to prevent disease in animals by infectious agents. Through the elimination of agents of infectious diseases in the environment, it is able to interrupt the mechanisms of the epizootic process. For the development of beekeeping and obtaining quality and products, it is necessary to carry out activities in apiaries, which include disinfection. The introduction of new disinfectants in the field is possible after preliminary laboratory tests. The aim of our research objective to investigate the resistance of a mixed bacterial culture isolated from bees with the symptoms of dysbiosis to disinfectant under laboratory conditions. Bacteriological investigations carried out in Petri dishes using meat-peptone agar and Mueller-Hinton agar. The disinfectant diluted with distilled water at concentrations of 0.25 %, 0.5 %, 1,25 % and 2,5 %. On the Mueller Hinton agar, the bacterial elimination zones recorded at 1.25 % (11,6 ± 0,45 mm) and 2.5 % (12,4 ± 0,27 mm) concentration of disinfectant at 1 day of investigation, and 7,4 ± 0,27 mm (1,25 %), 11,2 ± 0,42 mm (2.5 %) at 72 hours of the experiment, respectively. In addition, the bacterial growth inhibition effect increased with experimental time and ranged from 24.0 ± 0.35 mm (0.5 %) to 28.2 ± 0.22 mm (2.5 %) on day 3 of the study. Bacteriostatic and bactericidal effects appeared to be less pronounced on meat-peptone agar. The highest diameters of inhibition of the processes of reproduction and development of microorganisms from mixed microbial association on this medium were recorded at 1.25 % and 2.5 % concentrations of the disinfectant at the 3rd day of the investigation with diameters of the zones of inhibition of growth 15.6 ± 0.45 mm and 26.4 ± 0.27 mm, respectively. The specificity of diffusion of the investigated active substance from the discs into the agar medium thickness was also noted. This effect has a varying effect on infectious agents in in vitro experiments. Thus bacteriological laboratory experiments should be performed on several culture media in purpose of obtaining accurate results. The analysis of the obtained results indicates the demonstration of antimicrobial effect of the investigated disinfectant against mixed bacterial culture in the form of bactericidal and bacteriostatic actions. Therefore, a promising direction of research for veterinary doctors and apiary business owners is the search for effective and efficient disinfectants. Laboratory investigation of the activity of a remedy are the first step before it is approbation.

A Nanocomposite Dynamic Covalent Cross-Linked Hydrogel Loaded with Fusidic Acid for Treating Antibiotic-Resistant Infected Wounds.

Methicillin-resistant Staphylococcus aureus (MRSA) is associated with high levels of morbidity and is considered a difficult-to-treat infection, often requiring nonstandard treatment regimens and antibiotics. Since over 40% of the emerging antibiotic compounds have insufficient solubility that limits their bioavailability and thus efficacy through oral or intravenous administration, it is crucial that alternative drug delivery products be developed for wound care applications. Existing effective treatments for soft tissue MRSA infections, such as fusidic acid (FA), which is typically administered orally, could also benefit from alternative routes of administration to improve local efficacy and bioavailability while reducing the required therapeutic dose. Herein, we report an antimicrobial poly(oligoethylene glycol methacrylate) (POEGMA)-based composite hydrogel loaded with fusidic acid-encapsulating self-assembled polylactic acid-b-poly(oligo(ethylene glycol) methyl ether methacrylate) (PLA-POEGMA) nanoparticles for the treatment of MRSA-infected skin wounds. The inclusion of the self-assembled nanoparticles (380 nm diameter when loaded with fusidic acid) does not alter the favorable mechanical properties and stability of the hydrogel in the context of its use as a wound dressing, while fusidic acid (FA) can be released from the hydrogel over ∼10 h via a diffusion-controlled mechanism. The antimicrobial studies demonstrate a clear zone of inhibition in vitro and a 1-2 order of magnitude inhibition of bacterial growth in vivo in an MRSA-infected full-thickness excisional murine wound model even at very low antibiotic doses. Our approach thus can both circumvent challenges in the local delivery of hydrophobic antimicrobial compounds and directly deliver antimicrobials into the wound to effectively combat methicillin-resistant infections using a fraction of the drug dose required using other clinically relevant strategies.

Glycerine addition in Cashew stembark extract mouthwash influence the inhibition of bacterial growth

The part of cashew plant (Anacardium Occidentale Linn) can be utilized as an ingredient in herbal medicine. Alkaloids, tannins, and flavonoids found in cashew stembark exhibit broad-spectrum antibacterial activity, making them appropriate as an active ingredient in mouthwash. On the other hand, one of the key ingredients in mouthwash formulas is glycerin. It is also frequently used as humectant. This study aims to prove the effect of glycerin on the cashew stembark extract mouthwash on its antibacterial activity. This study used 4 formulas consisted of 7% concentration of cashew stembark extract added with 1% sorbitol, 1.5% peppermint, distilled water as solvent, and various concentration of glycerin for each formula. The clarity, color change, and taste were assessed at day 7. The growth inhibition of both gram positive (S. aureus) and gram negative (P. aeruginosa) bacteria was measured. The data obtained were tested using one-way ANOVA and LSD (α=0.05). All of the 4 formulas of the mouthwashes found to be relatively stable. Based on the results of the inhibition test, it can be concluded that the addition of glycerin affects the inhibition of S. aureus and P. aeruginosa bacteria. Glycerin had significant effect on bacterial growth inhibition at 15% (Formula III).

Antibacterial Activity of Plant Polyphenols Belonging to the Tannins against Streptococcus mutans-Potential against Dental Caries.

Dental caries (DC) is the most common oral pathology. The main bacteria responsible for DC is Streptococcus mutans. One of the strategies that can decrease or eliminate the risk of DC development is using compounds that will inhibit both the growth and virulence factors of S. mutans. Tannins are plant polyphenols that have strong antibacterial activity. The purpose of this study was to assess the antibacterial activity of three tannins against S. mutans. In this investigation, microbiological tests (MIC and MBC) and physicochemical techniques like the fluorescence measurements of tannins' interaction with S. mutans cell membrane and membrane proteins, zeta potential, and thermodynamic analyses were used to obtain knowledge about the antibacterial potential of the investigated compounds against S. mutans as well as about the mechanisms associated with antibacterial activity. The obtained results demonstrate that the used compounds exhibit high antibacterial activity against S. mutans. The mechanisms of their antibacterial activity are linked to the strong change in the S. mutans membrane fluidity and potential, and to their interaction with membrane proteins that can result in great disturbance of bacterial physiology and ultimately the inhibition of bacterial growth, triggering their death. Therefore, it can be concluded that the investigated compounds can be potentially used as natural factors in the prevention of dental caries.

Utilization of nanotechnology and experimental design in the development and optimization of a posaconazole‒calendula oil nanoemulgel for the treatment of mouth disorders.

Introduction: Essential oil‒based nanoemulsions (NEs) are the subjects of extensive investigation due to their potential to address a variety of oral health issues. NEs are delivery systems that improve lipid medicine solubility and distribution to intended sites. The goal of the current study was to create and enhance a self-nanoemulsifying drug delivery paradigm based on calendula oil (CO) and decorated with chitosan (CS) that could deliver posaconazole (PSZ) for the treatment of gingivitis. Method: Employing a response-surface Box‒Behnken design, PSZ-CO-CS NEs were created with varying amounts of PSZ (10, 15, and 20mg), percentages of CO (6%, 12%, and 18%), and percentages of CS (0.5%, 1.5%, and 2.5%). Results and conclusion: The optimized formulation resulted in a 22-mm bacterial growth suppression zone, 25-mm fungal growth inhibition zone, droplet sizes of 110nm, and a viscosity of 750 centipoise (cP). Using the appropriate design, the ideal formulation was produced; it contained 20mg of PSZ, 18% of CO, and 1.35% of CS. Furthermore, the optimal formulation had a more controlled drug release, larger inhibition zones of bacterial and fungal growth, and desirable rheologic properties. Additionally, the optimized formulation substantially lowered the ulcer index in rats when tested against other formulations. Thus, this investigation showed that PSZ-CO-CS NEs could provide efficient protection against microbially induced gingivitis.

Structural, morphological and optical properties of ZnFe2O4-decorated reduced graphene oxide nanocomposite for antibacterial applications

In this study, the zinc ferrite decorated reduced graphene oxide (ZnFe2O4-rGO) was synthesised by using a simplified one-pot solvothermal technique. The synthesised nanomaterials were examined for structural, morphological and optical characteristics is greatly aided by the XRD, HRTEM, SAED, EDX spectroscopy, Raman spectroscopy and UV–Vis spectroscopy. The crystallite size calculated from XRD and HRTEM of the ZnFe2O4-rGO nanocomposite was around 10 nm. The presence of desired elements in the synthesised nanomaterials was confirmed using EDX spectroscopy. The Raman spectroscopy aided in identifying the active functional modes. The absorption maximum (λmax) was found to be approximately ∼310 nm and the optical bandgap of ZF was reduced from 2.1 eV to 1.97 eV in ZF-rG. The antibacterial activity of ZnFe2O4-rGO nanocomposite was discussed against Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumonia and Escherichia coli bacteria at different concentrations by agar gel diffusion method among which the highest bacterial growth inhibition was seen in Klebsiella pneumonia in all different concentrations in which 86% at 100 μg/ml was the most effective.

Bacteriophage and antibiotic combination therapy for recurrent Enterococcus faecium bacteremia.

Phage therapy is an emerging therapeutic approach for treating bacterial infections that do not respond to traditional antibiotics. The addition of phage therapy to systemic antibiotics to treat a patient with recurrent E. faecium infections that were non-responsive to antibiotics alone resulted in fewer hospitalizations and improved the patient's quality of life. Combination phage and antibiotic therapy reduced E. faecium and VRE abundance in the patient's stool. Eventually, an anti-phage antibody response emerged that was able to neutralize phage activity, which may have limited clinical efficacy. This study demonstrates the potential of phages as an additional option in the antimicrobial toolbox for treating invasive enterococcal infections and highlights the need for further investigation to ensure phage therapy can be deployed for maximum clinical benefit.

UJI AKTIVITAS ANTIBAKTERI EKSTRAK DAUN ASAM JAWA (Tamarindus indica L) TERHADAP BAKTERI Propionibacterium acne DAN BAKTERI Pseudomonas aeruginosa

The goal of this research is to find out the capability of tamarind leaf ethanol extract (Tamarindus indica Linn) to inhibit the maturationof Propiomibacterium acnes and Pseudomonas aeruginosa bacteria as well as the optimal concentration of tamarind leaf extract that can do so. Using 96% ethanol as a solvent, maceration was used for extraction. Antibacterial activity testing uses the agar diffusion method by means of discs. According to studies on the antibacterial action of tamarind leaf ethanol extract opposed tothe bacteria Propionibacterium acne and Psedomonas aeruginosa, at a concentration of 20%, the extract can already block the development of bacteria in the medium range, while at a concentration of 80%, the extract can inhibit bacterial growth in the strong category. The one-way anova method and the LSD test were used to examine the antibacterial activity test findings. According to Anova data, the test bacteria were suppressed at doses of 20%, 40%, 60%, & 80%. Effective concentrations to inhibit Propionibacterium acne bacteria and Pseudomonas aeruginosa bacteria at concentrations of 20%, 40%, 60%, & 80%. The measurement of the area of bacterial growth inhibition increases with tamarind leaf extract concentration. Flavonoids, alkaloids, saponins, tannins, and steroids can be found in tamarind leaf ethanol extract. Tamarind leaf ethanol extract has antibacterial activity against Propionicaterium acne and Pseudomonas aeruginosa bacteria and has an inhibition zone at 80% concentration with an average diameter of 25.83 cm and 17.66 cm.

Versatile Antibacterial and Antioxidant Bacterial Cellulose@Nanoceria Biotextile: Application in Reusable Antimicrobial Face Masks.

Despite considerable interest in medical and pharmaceutical fields, there remains a notable absence of functional textiles that concurrently exhibit antibacterial and antioxidant properties. Herein, a new composite fabric constructed using nanostructured bacterial cellulose (BC) covalently-linked with cerium oxide nanoparticles (BC@CeO2NPs) is introduced. The synthesis of CeO2NPs on the BC is performed via a microwave-assisted, in situ chemical deposition technique, resulting in the formation of mixed valence Ce3+/Ce4+ CeO2NPs. This approach ensures the durability of the composite fabric subjected to multiple washing cycles. The Reactive oxygen species (ROS) scavenging activity of CeO2NPs and their rapid and efficient eradication of >99% model microbes, such as Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus remain unaltered in the composite. To demonstrate the feasibility of incorporating the fabric in marketable products, antimicrobial face masks are fabricated with filter layers made of BC@CeO2NPs cross-linked with propylene or cotton fibers. These masks exhibit complete inhibition of bacterial growth in the three bacterial strains, improved breathability compared to respirator masks and enhanced filtration efficiency compared to single-use surgical face masks. This study provides valuable insights into the development of functional BC@CeO2NPs biotextiles in which design can be extended to the fabrication of medical dressings and cosmetic products with combined antibiotic, antioxidant and anti-inflammatory activities.

Hypervirulent Capsular Serotypes K1 and K2 Klebsiella pneumoniae Strains Demonstrate Resistance to Serum Bactericidal Activity and Galleria mellonella Lethality.

Hypervirulent Klebsiella pneumoniae (hvKp) is a variant that has been increasingly linked to severe, life-threatening infections including pyogenic liver abscess and bloodstream infections. HvKps belonging to the capsular serotypes K1 and K2 have been reported worldwide, however, very scarce studies are available on their genomics and virulence. In the current study, we report four hypermucoviscous extended-spectrum β-lactamase-producing hvKp clinical strains of capsular serotype K1 and K2 isolated from pus and urine of critically ill patients in tertiary care hospitals in Oman. These strains belong to diverse sequence types (STs), namely ST-23(K1), ST-231(K2), ST-881(K2), and ST-14(K2). To study their virulence, a Galleria mellonella model and resistance to human serum killing were used. The G. mellonella model revealed that the K1/ST-23 isolate was the most virulent, as 50% of the larvae died in the first day, followed by isolate K2/ST-231 and K2/ST-14, for which 75% and 50% of the larvae died in the second day, respectively. Resistance to human serum killing showed there was complete inhibition of bacterial growth of all four isolates by the end of the first hour and up to the third hour. Whole genome sequencing (WGS) revealed that hvKp strains display a unique genetic arrangement of k-loci. Whole-genome single-nucleotide polymorphism-based phylogenetic analysis revealed that these hvKp isolates were phylogenetically distinct, belonging to diverse clades, and belonged to different STs in comparison to global isolates. For ST-23(K1), ST-231(K2), ST-881(K2), and ST-14(K2), there was a gradual decrease in the number of colonies up to the second to third hour, which indicates neutralization of bacterial cells by the serum components. However, this was followed by a sudden increase of bacterial growth, indicating possible resistance of bacteria against human serum bactericidal activity. This is the first report from Oman detailing the WGS of hvKp clinical isolates and assessing their resistance and virulence genomics, which reinforce our understanding of their epidemiology and dissemination in clinical settings.

(128) Characterizing Antibiotic Susceptibility of the Penile Prosthesis Microbiome

Abstract Introduction Inflatable penile prostheses (IPP) are the gold standard treatment for erectile dysfunction refractory to conservative therapies. However, infection remains a significant concern and the presence of microbial biofilms on both infected and non-infected devices has recently been demonstrated. Various antimicrobials are used for prophylaxis intraoperatively and postoperatively. It remains unknown how these antimicrobials affect the growth of bacteria and their associated biofilms. We sought to assess how commonly used antimicrobials influenced growth of bacterial isolates previously isolated from both non-infected and infected devices, obtained during revisional surgery. Objective The goal of this study was to evaluate growth of bacterial isolates previously obtained from non-infected and infected IPPs. Isolates were exposed to single or multi-antibiotic combinations to assess degree of inhibition of bacterial growth. Methods In this IRB-approved study, 35 bacterial isolates had been previously obtained from patients who had been consented for IPP revision or replacement secondary to mechanical failure, pain, or device infection. Bacteria were plated on brain-heart-infusion (BHI) agar plates and allowed to incubate for 48 hours. Standard-sized antibiotic discs were introduced into the grown bacterial colonies consisting of the following single or multi-agent regimens: bacitracin, cefaclor, cephazolin, gentamicin, levofloxacin, trimethoprim-sulfamethoxazole, tobramycin, vancomycin, piperacillin/tazobactam, gentamicin + piperacillin/tazobactam, gentamicin + cephazolin, and gentamicin + vancomycin. Zones of inhibition (ZOI) were measured after placement of the antibiotic discs in the bacterial colonies. Statistics were analyzed with false discovery rate corrected, one-sample t-tests. Quantification of antibiotic resistance was defined as follows: Resistant: ZOI not significantly different from 0 in one sample t-test Susceptible: ZOI significantly greater than 0, but mean is <10mm Highly susceptible: ZOI significantly greater than 0, but mean is 10-20mm Exceptionally susceptible: ZOI significantly greater than 0, but mean is >20mm Taxonomic classification of bacterial isolates was provided by extracting DNA from pure cultures and sequencing the full length 16S rRNA gene using Sanger sequencing, after amplification with two different primer sets to provide overlapping sequence regions. Results Of the antibiotics tested, TMP-SMX was found to have the highest percentage of resistant isolates (54.3%) of the 35 tested, with bacitracin having the second most (40%). Both tobramycin and TMP-SMX had 0.0% of isolates be exceptionally susceptible. Combination piperacillin/tazobactam was found to have the highest percentage of exceptionally susceptible isolates (11.4%). A large majority of isolates were highly susceptible to gentamicin + piperacillin/tazobactam (91.4%), piperacillin/tazobactam (74.3%), gentamicin + cefazolin (74.3%), and levofloxacin (88.6%), while greater than half of isolates were highly susceptible to cefazolin (62.9%) and cefaclor (54.3%)." Conclusions Our results demonstrate that cefaclor or bacitracin prevented growth of bacterial isolates obtained from IPPs explanted for mechanical failure, pain or infection. Further investigation is needed to characterize how intraoperative and postoperative antibiotic influences a symbiotic or dysbiotic community of microbes on the surface of penile prostheses. By better understanding the interactions between microbes, antibiotics and host, novel therapeutics might promote a non-infected, symbiotic microenvironment. Disclosure Yes, this is sponsored by industry/sponsor: Coloplast corporation. Clarification: Industry funding only - investigator initiated and executed study. Any of the authors act as a consultant, employee or shareholder of an industry for: Coloplast, boston scientific.

A protocol for cloning, expression, and purification of Lysine exporter (LysE) gene of Mycobacterium tuberculosis

Background Tuberculosis (TB) is among the deadliest diseases and a significant cause of illnessacross the globe. Several studies on mycobacterial proteins, such as proteases and transporters that are essential for survival and pathogenesis have aimed to develop an efficient anti-tubercular agent. In mycobacterium, lysine exporter (LysE) is an amino acid transporter and a probable target for an anti-tubercular agent as it is responsible for bacterial growth inhibition and is also absent in the widely used Bacillus Calmette-Guérin (BCG) vaccine. Methods Some studies have purified LysE using different protocols. This study describes a protocol for purifying different constructs of LysE, focusing on its hydrophobic region using immobilized metal affinity chromatography (IMAC) after expressing LysE gene in a bacterial expression system. pET vector (pET28a) is used as an expression vector. Amplified LysE gene is ligated with the pET28a vector, and the resultant plasmid is then transformed into E. coli cells. The vector has a histidine tag that makes the purification process convenient. After IMAC, the samples will be subjected to size-exclusion chromatography for further purification. Results Cloning and amplification findings will be analyzed using 1% agarose gel, and protein expression and purification outcomes will be examined using sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Domain-specific constructs of LysE can be further analyzed as an anti-tubercular agent. Conclusions Despite being a potential anti-tubercular target, research is quite limited on this protein. Therefore, we aim to purify LysE protein for further analysis. Similar protocols have already been implemented to purify several other bacterial proteins with >95% purity.

Fluidization of biological membranes by hydrophobic molecules causes inhibition of bacterial growth

Fluidization of biological membranes by hydrophobic molecules causes inhibition of bacterial growth

Comparative evaluation of antimicrobial efficacy of triple antibiotic paste and amoxicillin clavulanate paste as an intracanal medicament against Enterococcus faecalis: An in vitro study

Background: Triple antibiotic paste (TAP) is the commonly used intracanal medicament against Enterococcus faecalis. Amoxicillin clavulanate paste (ACP) is recommended as a “fall-back” antibiotic when traditional dental antibiotics fail. Literature comparing the antimicrobial efficacy of TAP and ACP in eradicating E. faecalis from the root canal system is sparse; hence, this in vitro study was conducted to evaluate and compare the antimicrobial efficacy of TAP and ACP as an intracanal medicament for endodontic treatment of single-rooted permanent teeth against E. faecalis. Materials and Methods: This in vitro, experimental study evaluated 60 root samples obtained from extracted single-rooted human permanent teeth. The canal diameter was enlarged and subsequently infected with E. faecalis for 21 days. Four groups of the contaminated samples were treated with TAP, ACP, calcium hydroxide (positive control), and saline (negative control), respectively. Dentinal shavings were collected at the end of the 1st, 7th, and 10th day and inoculated in agar plates. The number of colony-forming units was determined, and the data were statistically analyzed using the Kolmogorov–Smirnov and Shapiro–Wilks test. P <0.05 was considered statistically significant. Results: The mean number of E. faecalis colony counts across all 3 test days demonstrated that TAP exhibited the highest inhibition of bacterial growth, followed by ACP which is not statistically significant (P = 1.00). Conclusion: Considering the limitations of this in vitro study, the findings suggest that ACP could be an effective alternative intracanal medicament to TAP for endodontic therapy.

Characterization of Antibiofilm and Antimicrobial Effects of Trigona Stingless Bee Honey Compared to Stinging Bee Centaurea hyalolepis and Citrus Honeys.

The antibiofilm and antimicrobial properties of tropical honey types including Malaysian stingless bee honey remain explicitly unexplored when compared with Apies honey. The antibiofilm and antimicrobial activities of the Malaysian Trigona honey were characterized with two stinging bee honey types (Centaurea hyalolepis and Citrus honeys) from Jordan. The antibiofilm and antimicrobial investigations were conducted on a set of seven microbial strains; five bacterial species of Pseudomonas aeruginosa ATCC 10145, Streptococcus pyogenes ATCC 19615, Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 13883, and two fungal strains Candida albicans ATCC 10231 and Candida krusei ATCC 14243. The antimicrobial investigations revealed a broad spectrum activity for Trigona honey against Gram-positive, Gram-negative, and fungal strains over the two honey types. One-way ANOVA showed a significant difference (p < 0.001) in the zone of inhibition ranging from 9 to 25 mm and minimum inhibition activity (MIC) ranged from 9.4-29.6% (w/v) against the microbial strains. Moreover, the addition of honey to established biofilms has induced a degradation activity in the biofilm mass. Two-way ANOVA showed a significant biofilm degradation proportion (p < 0.001) ranging from 1.3% to 91.3% following treatment with Trigona honey and the other honey types in relevance to the concentration ranging from 10% to 50% (w/v). Moreover, the antibiofilm activity was highly consistent with MIC affecting bacterial growth inhibition. In conclusion, a robust antimicrobial and antibiofilm activity for Trigona stingless bee honey over the stinging bee Centaurea hyalolepis and Citrus honeys is noticed which endows the usage of Trigona honey in the antimicrobial industry.

Antioxidant, antibacterial and antiviral effects of the combination of ginger and garlic extracts.

Garlic and ginger are well known as safe alternatives to traditional therapies. Limited information exists regarding antioxidant, antibacterial and antiviral capabilities of the combination of ginger and garlic. Standard methodologies were employed to determine the phytochemical compositions. Antioxidant activities were evaluated through DPPH and FRAP assays. Notably, in DPPH assay, combination of ginger and garlic extracts displayed significantly higher (85.44%, p < 0.005) antioxidant activity even at lower concentrations (6 mg/ml) compared to ginger and garlic extracts alone. Similar findings were observed for FRAP assay. At low concentration of extracts (25 µg/ml), combination of ginger and garlic exhibited significant (p < 0.005) increase in reducing activity (51%) compared to ginger or garlic extracts alone. Significant antibacterial and antiviral activities were exhibited by the combination of both ginger and garlic extracts as compared to ginger and garlic extracts alone. The combined effect of garlic and ginger exhibited a synergistic effect in bacterial and viral growth inhibition. These findings suggest that the diverse phytochemical compositions of the ginger and garlic varieties contribute to their strong antioxidant properties, potentially positioning them as valuable therapeutics for bacterial and viral infections. Further analysis will be required for their widespread utilization and pharmaceutical applications.

The Investigation of Changes in Bacterial Community of Pasteurized Milk during Cold Storage

The quality of pasteurized milk is commonly assessed through microbiological analysis, with variations in storage conditions significantly impacting the suppression of bacterial growth throughout the milk’s shelf life. This study investigated the dynamics of total bacterial counts (TBCs) and bacterial community shifts in milk that underwent pasteurization at 80 °C for 15 s. The milk was subsequently stored at 4 °C for varying intervals of 1, 4, 7, 10, 13, and 16 days. Culture-based testing revealed a significant TBC increase during the storage period spanning 1 to 16 days (up to −log10 4.2 CFU/mL at day 16). The TBC in pasteurized milk exhibited accelerated microbial growth from day 13 onwards, ultimately peaking on day 16. Bacillus was detected through 16S rRNA identification. Principal component analysis demonstrated a significant impact of storage time on bacterial communities in pasteurized milk. Analysis of bacterial diversity revealed a negative correlation between the Shannon index and the duration of pasteurized milk storage. Using high-throughput sequencing, Streptococcus and Acinetobacter were detected as prevalent bacterial genera, with Streptococcus dysgalactiae and Streptococcus uberis showing as dominant taxa. The presence of Streptococcus dysgalactiae and Streptococcus uberis in pasteurized milk might be attributed to the initial contamination from raw milk with mastitis. This study offers new evidence of the prevalence of bacterial community in pasteurized milk, thereby adding value to the enhancement of quality control and the development of strategies for reducing microbial risks.