Inhibition Of Bacterial Growth Research Articles

Exploring the Antibacterial Effects of Ozonated Oils in Medicine: A Study on Escherichia coli Inhibition

ABSTRACT Ozonated oil has a long tradition in medical therapy. Here, the results from previous studies regarding the antibacterial effects of ozonated oils were compared. In addition, the aim of this study was to further examine the antibacterial activity against Escherichia coli for two different ozonated oils, in regard to the ozone exposure time and amount. Using agar dilution, the minimum inhibitory concentration of the oils was studied. For all of the tested concentrations with the agar dilution method, bacterial growth was observed. Furthermore, agar dilution was combined with spread-plating to determine the inhibition zone with and without the emulsifier. The emulsifier-free and emulsifier-containing experiments with agar dilution and spread-plating did not result in an inhibition of bacterial growth by ozonated oils. Moreover, the bacteria were exposed to the oils for various intervals before being grown on either solid or liquid medium to determine the time-dependent antibacterial effects of the ozonated oil. For both media, the results were compared to non-ozonated oil and NaCl solution as a negative control. The bacteria in the solid medium were already completely inactivated after 5 min of exposure with the ozonated oil. For the liquid medium, also shorter exposition times were investigated. After 1 min, there was no inhibition in the ozonated oils with the liquid medium. After 5 min, the bacterial growth in the ozonated oils was significantly reduced in the liquid medium.

Antibacterial Biomaterial Based on Bioglass Modified with Copper for Implants Coating.

Biofilm-related implant infections pose a substantial threat to patients, leading to inflammation in the surrounding tissue, and often resulting in implant loss and the necessity for additional surgeries. Overcoming this implantology challenge is crucial to ensure the success and durability of implants. This study shows the development of antibacterial materials for implant coatings by incorporating copper into 45S5 Bioglass®. By combining the regenerative properties of Bioglass® with the antimicrobial effects of copper, this material has the potential to prevent infections, enhance osseointegration and improve the long-term success of implants. Bioglasses modified with various concentrations of CuO (from 0 to 8 mol%) were prepared with the melt-quenching technique. Structural analysis using Raman and FTIR spectroscopies did not reveal significant alterations in the bioglasses structure with the addition of Cu. The antibacterial activity of the samples was assessed against Gram-positive and Gram-negative bacteria, and the results demonstrated significant inhibition of bacterial growth for the bioglass with 0.5 mol% of CuO. Cell viability studies indicated that the samples modified with up to 4 mol% of CuO maintained good cytocompatibility with the Saos-2 cell line at extract concentrations up to 25 mg/mL. Furthermore, the bioactivity assessment demonstrated the formation of a calcium phosphate (CaP)-rich layer on the surfaces of all bioglasses within 24 h. Our findings show that the inclusion of copper in the bioglass offers a significant enhancement in its potential as a coating material for implants, resulting in notable advancements in both antibacterial efficacy and osteointegration properties.

Moxifloxacin HCl-Incorporated Aqueous-Induced Nitrocellulose-Based In Situ Gel for Periodontal Pocket Delivery.

A drug delivery system based on an aqueous-induced in situ forming gel (ISG) consists of solubilizing the drug within an organic solution of a polymer using a biocompatible organic solvent. Upon contact with an aqueous medium, the solvent diffuses out and the polymer, designed to be insoluble in water, solidifies and transforms into gel. Nitrocellulose (Nc), an aqueous insoluble nitrated ester of cellulose, should be a promising polymer for an ISG using water induction of its solution to gel state via phase inversion. The aim of this investigation was to develop and evaluate a moxifloxacin HCl (Mx)-incorporated aqueous-induced Nc-based ISG for periodontitis treatment. The effects of different solvents (N-methyl pyrrolidone (NMP), DMSO, 2-pyrrolidone (Py), and glycerol formal (Gf)) on the physicochemical and bioactivity properties of the ISGs were investigated. The viscosity and injection force of the ISGs varied depending on the solvent used, with Gf resulting in higher values of 4631.41 ± 52.81 cPs and 4.34 ± 0.42 N, respectively. All ISGs exhibited Newtonian flow and transformed into a gel state upon exposure to the aqueous phase. The Nc formulations in DMSO showed lower water tolerance (12.50 ± 0.72%). The developed ISGs were easily injectable and demonstrated water sensitivity of less than 15.44 ± 0.89%, forming a gel upon contact with aqueous phase. The transformed Nc gel effectively prolonged Mx release over two weeks via Fickian diffusion, with reduced initial burst release. Different solvent types influenced the sponge-like 3D structure of the dried Nc ISGs and affected mass loss during drug release. Incorporating Nc reduced both solvent and drug diffusion, resulting in a significantly narrower zone of bacterial growth inhibition (p < 0.05). The Mx-incorporated Nc-based ISGs exhibited efficient antibacterial activity against four strains of Staphylococcus aureu and against periodontitis pathogens including Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis. This study suggests that the developed Mx-incorporated Nc-based ISGs using DMSO and NMP as the solvents are the most promising formulations. They exhibited a low viscosity, ease of injection, and rapid transformation into a gel upon aqueous induction, and they enabled localized and prolonged drug release with effective antibacterial properties. Additionally, this study represents the first reported instance of utilizing Nc as the polymer for ISG. Further clinical experiments are necessary to evaluate the safety of this ISG formulation.

Natural nanogels crosslinked with S-benzyl-L-cysteine exhibit potent antibacterial activity

Biofilm-forming bacteria E. coli and P. aeruginosa have both exhibited resistance against multiple antibiotics in clinical settings. To find a solution, researchers have turned to antibacterial structurally modified from natural materials that are harmless to the human body. Among these is DNA, a natural polymer composed of deoxyribose that when treated with HCl exposes its aldehyde groups and produces DNA-HCl. Here, we crosslinked these aldehyde groups with the primary amines in S-benzyl-L-cysteine (SBLC) using a Schiff reaction to obtain DNA-HCl-SBLC. We additionally treated alginate acid (AA) with EDAC, obtaining AA-EDAC, and substituting it with SBLC to produce AA-SBLC. We incorporated the above reactions with an emulsification process to produce nanogels (NGs) that were verified to be spherical and possessing benzene rings successfully grafted onto DNA-HCl and AA-EDAC. These natural NGs were proven to be negatively charged through zeta potential analysis and presented low cytotoxicity toward normal cells in cell organoid viability assays. These SBLC-modified polymers provided better inhibition of bacterial growth than those without modification. Moreover, after incubation with SBLC-modified NGs, bacteria expressed intracellular recA or pvdA in a dose-dependent manner, which was consistent with SEM data from damaged bacteria. Out of four tested NGs, DNA-HCl-SBLC NGs suppressed P. aeruginosa-induced sepsis most effectively and extended the lifespan of C. elegans. This study provides an alternative clinical solution to antibiotics-resistant biofilm strains.

Tannic acid-layered hydroxide salt hybrid: assessment of antibiofilm formation and foodborne pathogen growth inhibition.

Pathogenic bacteria in food are a public health problem worldwide. Polyphenolic bioactive compounds with antimicrobial activity and antioxidant capacity represent a tangible alternative to overcome this problem. To preserve the biological functions of phenolic compounds such as tannic acid, which has been described to possess antioxidant and antimicrobial activity, this study describes the synthesis of a zinc nanohydroxide to stabilize its properties. Characterization by XRD, FT-IR, SEM, DLS, and UV-vis evidenced the presence of tannic acid in the nanohybrid TA-Zn-LHS which was further confirmed by DPPH, ABTS and FRAP antioxidant activity techniques. Bacterial growth inhibition of Escherichia coli ATCC 8739, Salmonella Enteritidis, and Staphylococcus aureus ATCC 25923 was over 80% at 50mg/mL of the TA-Zn-LHS and over 90% with Zn-LHS. Antibiofilm evaluation of these same strains showed biofilm formation inhibition > 90% and > 80% for Zn-LHS and TA-Zn-LHS, respectively. The toxicity evaluation of the materials in Artemia salina showed a classification of the materials as non-toxic to slightly toxic in concentrations up to 1mg/mL. These results allow us to introduce a new nanohybrid useful for food safety with safe biological functions.

Release and antibacterial action of phenolic acids incorporated into PHBV films

Ferulic or p-coumaric acids were incorporated (3, 6 or 9%) into PHBV films by melt processing or surface anchoring (3–4% in the film). The release kinetics of phenolics and the films’ antibacterial effect against Escherichia coli and Listeria innocua were analysed. At equilibrium, a near 100% release of phenolics was obtained from melt processed films in a low polar simulant (D1: 50% v/v ethanol in water), whereas it ranged between 10% and 38% in a more polar simulant (A: 10% v/v ethanol in water). The diffusion coefficient of FA or PCA in the matrix also rose by 4–30 times in contact with simulant D1. The limited release of the phenolics in contact with aqueous systems hindered the film’s antibacterial effect in contact with the inoculated culture media. In contrast, surface-loaded films exhibited a complete release of phenolics in aqueous media and a significant (near 2 log CFU) bacterial growth inhibition.

Antibacterial Superhydrophobic Cotton Fabric with Photothermal, Self-Cleaning, and Ultraviolet Protection Functionalities.

Cotton fabrics with superhydrophobic, antibacterial, UV protection, and photothermal properties were developed using Ag/PDMS coatings, and the role of coating formulations on the obtained functionalities was studied. Specific attention was paid to understanding the relationships between the fabrics' superhydrophobicity and antibacterial activity against Escherichia coli (E. coli) bacteria. UV protection performance of Ag/PDMS coatings was thoroughly evaluated based on the variation of UV transmission rate through coated fabrics and photoinduced chemiluminescence spectra. Moreover, the effect of silver nanoparticles (Ag NPs) and PDMS on developing a photothermal effect on fabrics was discussed. It was found that the content of Ag NPs and PDMS played critical roles in determining the water contact angle (WCA) on modified fabrics. The largest WCA was 171.31°, which was durable even after numerous accelerated wash cycles and abrasions. Antibacterial activity of fabrics showed the positive effect of pure PDMS in bacterial growth inhibition. Moreover, it was found that the antibacterial performance was greatly affected by the content of Ag NPs loaded on fabrics rather than their superhydrophobic status. Moreover, increasing the content of Ag NPs boosted the UV protection level of fabrics, improved fabrics photostability, and reduced the UV transmission rate through fabrics. Testing the photothermal effect confirmed that the content of Ag NPs and PDMS both played prominent roles, where Ag acted as a photothermal agent and PDMS determined the NIR reflection rate from the coated surface. The modified fabrics were characterized using TGA, SEM, FTIR, and XRD techniques, and it was confirmed that using a higher amount of PDMS increased the amount of Ag NPs deposition on fabrics.

Evaluation of lipophosphoramidates-based amphiphilic compounds on the formation of biofilms of marine bacteria

The bacteriostatic and/or bactericidal properties of few phosphoramide-based amphiphilic compounds on human pathogenic bacteria were previously reported. In this study, the potential of two cationic (BSV36 and KLN47) and two zwitterionic (3 and 4) amphiphiles as inhibitors of marine bacterial growth and biofilm formation were investigated. Results showed that the four compounds have little impact on the growth of a panel of 18 selected marine bacteria at a concentration of 200 µM, and up to 700 µM for some bacterial strains. Interestingly, cationic lipid BSV36 and zwitterionic lipids 3 and 4 effectively disrupt biofilm formation of Paracoccus sp. 4M6 and Vibrio sp. D02 at 200 µM and to a lesser extent of seven other bacterial strains tested. Moreover, ecotoxicological assays on four species of microalgae highlighted that compounds 3 and 4 have little impact on microalgae growth with EC50 values of 51 µM for the more sensitive species and up to 200 µM for most of the others. Amphiphilic compounds, especially zwitterionic amphiphiles 3 and 4 seem to be promising candidates against biofilm formation by marine bacteria.

Centrifugally spun PVP/ZnO composite fibers with different surfactants and their use as antibacterial agents

AbstractPolyvinylpyrrolidone (PVP) fibers embedded with Zinc Oxide nanoparticles (ZnO NPs) were prepared by the centrifugal spinning of aqueous PVP solutions and ZnO NPs. The ZnO NPs were synthesized and coated with either cetyltrimethylammonium bromide or hexadecyltrimethylammonium bromide. The structure and morphology of the nanocomposite fibers were studied using scanning electron microscopy, X‐ray diffraction, energy‐dispersive X‐ray spectroscopy, Fourier transformed infrared spectroscopy and Thermogravimetric analysis. The effect of surfactant coating on the antibacterial activity of ZnO NPs and PVP/ZnO nanocomposite fibers against Escherichia coli (E. coli) and Bacillus megaterium (B. megaterium) bacteria was systematically investigated. The present study indicated that coating the ZnO NPs with surfactants resulted in large and uniform inhibition of bacterial growth.

To Evaluate the Antimicrobial Activity of PRP and PRF with and without Nanosilver.

To evaluate the antimicrobial activity of PRP and PRF with and without nanosilver. The materials were tested in powdered form is nanosilver. The nanosilver particles was mixed to form with PRP and PRF so as to placed in a wells followed the groups are experimental groups; Group I: PRP + nanosilver particles, Group II: PRF + nanosilver and control group: PRP and PRF and normal saline. Silver nanoparticles was tested at concentrations of 50 μ gram per mL. The powder was prepared for each group with identical amount of the powder (milligram/mg) and then mixed with 1 milliliter liquid. The plates are then incubated at 37°C under appropriate atmospheric conditions (80% N2, 10% CO2, 10% H2) for 24 hours, 48 hours, and 72 hours under anaerobic conditions in a CO2 incubator. The diameters of the zones of bacterial and fungal growth inhibition around the wells containing the test substances are then recorded after the period of incubation. The inhibitory zone determined in millimeter by measuring scale the shortest distance between the outer margin of the well and initial microbial as well as fungal growth. The experiments were performed 20 times and the mean and standard deviations of the inhibitory zones were calculated. Platelet rich fibrin is mixed with nanosilver particles showed higher antimicrobial efficacy than platelet rich plasma with nanosilver and simple platelet rich plasma and platelet rich fibrin are equivalent when it is placed against the anaerobic bacteria E.faecalis and yeast like fungi Candida albicans, respectively. Groups presented with antimicrobial efficacy in this order- Group IV > Group II > Group III > Group I.

Assessing Contact Time and Concentration of Thymus vulgaris Essential Oil on Antibacterial Efficacy In Vitro.

The overuse and misuse of antibiotics can pose the risk of spreading mutant strains that show antimicrobial resistance (AMR), with negative impacts on the management of bacterial infections and economic implications for healthcare systems. The research and development of natural antibacterial agents could be a priority in the next years to improve a number of effective antibacterial molecules and to reduce the AMR phenomenon and its development. The present study identified the most effective concentration and contact time of Thymus vulgaris L. essential oil (TEO) to obtain bactericidal effects in vitro against different Gram-positive and Gram-negative bacterial strains. Six clinically isolated (wild types) bacterial strains, (Citrobacter freundii, Enterococcus feciorum, Proteus mirabilis, Acinetobacter cioffi, Pseudomonas putrefaciens and Klebsiella pneumoniae) and two ATCCs (Staphylococcus aureus and Streptococcus mutans) were tested after 1 min, 3 min and 5 min of contact with TEO. The preliminary results on S. aureus after 24 h of incubation revealed a TEO concentration of 9.28 mg/mL (w/v) that completely inhibited bacteria growth, keeping cell viability. The total suppression of bacterial growth at all tested contact times was observed for all tested bacterial strains, and the results were confirmed after 48 h of incubation. Bacterial growth suppression was confirmed even with the presence of organic components. These preliminary results showed the in vitro antimicrobial efficacy of TEO against different Gram-positive and Gram-negative bacterial strains. Future studies are necessary to confirm the reproducibility of these results even on other strains and to define the exact molecular mechanisms of EOs in order to consider TEO as a valid alternative to classic antibiotic therapies and subsequently to reduce the occurrence of AMR.

Antimicrobial Activity of The Ethanol Extract of Coffea canephora L. Seeds Against Staphylococcus aureus and Propionibacterium acnes

Acne is a skin disease that causes humans to lack confidence in carrying out activities. Besides being sick, acne worsens the beauty of human skin. The cause of acne is gram-positive bacteria, namely Staphylococcus aureus and Propionibacterium acnes. Many studies reported that Coffea canephora L can inhibit the growth of bacteria. The objective of this study is to establish the minimum inhibitory concentration (MIC) of the ethanol extract of robusta coffee seeds in inhibiting the growth of Staphylococcus aureus and Escherichia coli. The ethanol extract of C. canephora L seed was obtained by maceration method using 96% ethanol. The extract obtained was evaluated for its antibacterial activity using the agar diffusion method with perforation techniques. The extract was divided into five various concentrations (50%, 25%, 12.5%, 6.25%, and 3.125%). The results of this study indicated that the ethanol extract of coffee seeds with a concentration of 50% resulted in a wider diameter of the zone of inhibition of bacterial growth in S. aureus, 30.00 mm compared to P. acnes, 26.22 mm. The MIC of ethanol extract for S. aureus at 3.00% while P. acnes was 6.00%. In conclusion, the antibacterial effect of the ethanol extract of coffee seeds at 50% concentration was stronger against S. aureus bacteria than P. acnes. The greater the concentration of the extract, the wider the resulting inhibition zone.

The Effectiveness of Using Jengkol Peel Extract (Pithecellobium lobatum Benth.) in Inhibits Bacterial Growth Staphylococcus aureus In Vitro

Staphylococcus aureus is aerobic bacteria that are gram-positive and are one of the normal human flora on the skin and mucous membranes. Most infections in the oral cavity are caused by Staphylococcus aureus, which is a normal flora in the oral cavity that can turn into a pathogen if trauma or abrasion occurs on the mucosal surface. Jengkol peel is thought to contain tannin compounds, which have the potential as an anti-inflammatory, anti-diarrheal, antioxidant, treatment of infections of the skin and mouth, and treatment of burns. This study aimed to explore the potential of jengkol peel extract (Pithecellobium lobatum Benth.) as an antibacterial Staphylococcus aureus regularly in vitro. This study is an experimental research in vitro, where as many as 7 treatment groups were used in this study. Positive and negative controls and extract concentrations of 5%-80% were used as the treatment group. Analysis of the average diameter of the inhibition of bacterial growth was carried out using SPSS version 25 software. The potential inhibition of jengkol peel extract was in line with the increase in the concentration of jengkol peel extract. The higher the concentration of jengkol peel extract, the greater the inhibition of bacterial growth. Extract concentration of 20% has a comparable inhibition of bacterial growth control positive. Jengkol peel extract effectively inhibits the growth of Staphylococcus aureus bacteria. Jengkol peel extract concentration of 20% has effectiveness in inhibiting bacterial growth equivalent to 0.2% chlorhexidine in vitro.

Efficacy of wound cleanser 25% based on indonesian medicine plants on chronic wound healing

&#x0D; ABSTRACT&#x0D; Background: Chronic wounds are a challenge for wound care professionals and a global economic burden that has increased morbidity and mortality in patients worldwide.&#x0D; Purpose: This study aims to determine the efficacy of wound cleanser with guava leaf extract (Psidium guajava Linn) and betel leaf extract (Piper betle L) 25% on the inhibition of bacterial growth in chronic wounds.&#x0D; Methods: The research conducted was laboratory experimental in nature. Guava leaf extract (Psidium guajava Linn) and betel leaf extract (Piper betle L) were formulated in the form of liquid soap with a concentration of 25% then evaluation of the physical preparations, allergy tests and bacterial tests were carried out in the form of the inhibition of liquid soap against Pseudomonas aeruginosa bacteria, Staphylococcus aureus, Escherichia coli in chronic wounds, Bacillus subtilis, Bacillus cereus, Staphylococcus epidermidis and Yeast Candida Albicans. Data collection is carried out after passing the ethical test.&#x0D; Results: This proves that liquid soap preparations of ethanol extract of guava leaves (Psidium guajava Linn) and betel leaf extract (Piper betle L) have medium, strong and very strong inhibition against Pseudomonas aeruginosa (12.28 mm), Staphylococcus aureus (19.48 mm), Escherichia coli (13.94 mm), Bacillus subtilis (27.58 mm), Bacillus cereus (11.11 mm), Staphylococcus epidermidis (14.44 mm) and category of respond medium inhibition on Yeast Candida Albicans (8.13 mm).&#x0D; Conclusion: Based on the results of the study, it can be concluded that the formulation of liquid soap preparations of ethanol extract of guava leaves (Psidium guajava Linn) and betel leaf extract (Piper betle L) with a concentration of 25% fulfills the quality requirements for liquid soap preparations. The results of this liquid soap antibacterial test had a strong response in inhibiting the growth of the bacteria Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Bacillus cereus, Staphylococcus epidermidis.&#x0D; &#x0D; Keywords: Liquid soap, Psidium guajava Linn, Piper betle L, Bacteria&#x0D;

Expression and copper binding studies of a Plasmodium falciparum protein with Cox19 copper binding motifs

Copper can exist in an oxidized and a reduced form, which enables the metal to play essential roles as a catalytic co-factor in redox reactions in many organisms. Copper confers redox activity to the terminal electron transport chain cytochrome c oxidase protein. Cytochrome c oxidase in yeast obtains copper for the CuB site in the Cox1 subunit from Cox11 in association with Cox19. When copper is chelated in growth medium, Plasmodium falciparum parasite development in infected red blood cells is inhibited and excess copper is toxic for the parasite. The gene of a 26 kDa Plasmodium falciparum PfCox19 protein with two Cx9C Cox19 copper binding motifs, was cloned and expressed as a 66 kDa fusion protein with maltose binding protein and affinity purified (rMBP-PfCox19). rMBP-PfCox19 bound copper measured by: a bicinchoninic acid release assay; an in vivo bacterial host growth inhibition assay; ascorbate oxidation inhibition and differential scanning fluorimetry. The native protein was detected by antibodies raised against rMBP-PfCox19. PfCox19 binds copper and is predicted to associate with PfCox11 in the insertion of copper into the CuB site of Plasmodium cytochrome c oxidase. Characterisation of the proteins involved in Plasmodium spp. copper metabolism will help us understand the role of cytochrome c oxidase and this essential metal in Plasmodium homeostasis.

Hyaluronidase inhibitor surface-modified niosomes: An efficient strategy for antibacterial and anti-biofilm drug delivery

Bacterial infections caused by resistant strains have become one of the most significant life-threatening challenges. Therefore, the exploration of competent approaches is instantly required. We report multifunctional niosomes loaded with vancomycin (VCM) antibiotic and coated with antibacterial polyhexanide layer (PH) followed by a novel antivirulence polymer hyaluronic acid-N,N-Dibutylethylenediamine (HD), which exhibited efficient in vitro and in vivo anti-methicillin-resistant Staphylococcus aureus (MRSA) activity. HD-PH-coated niosomes had an average diameter, polydispersity index, zeta potential, and drug encapsulation efficiency of 153.7 ± 2.1 nm, 0.29 ± 0.04, − 9.46 ± 1.46 mV and 84.15 ± 1.11 %, respectively. The in vitro release showed a diffusion-based controlled VCM release profile. The binding affinity studies using Microscale thermophoresis and in silico techniques showed that HD competitively inhibited hyaluronate lyase enzyme even in the presence of its natural substrate, hyaluronic acid, resulting in better inhibition of colonization and biofilm formation of hyaluronate lyase producing bacteria. HD-PH-coated niosomes exhibited higher antibacterial and antibiofilm activity than the bare VCM and non-coated niosomes. Furthermore, the time-kill assay revealed a fast inhibition of bacterial growth with complete elimination of MRSA bacteria within the first 2 h of the study. In vivo studies against a mouse model of MRSA skin infection indicated that HD-PH-coated niosomes had a 29.6-fold reduction in MRSA load compared to bare VCM (p = 0.0006). Therefore, HD-PH coating was confirmed as a promising strategy for enhancing antibacterial and anti-biofilm drug delivery systems.

Antibacterial activity and anxiolytic-like effect of Ziziphus joazeiro Mart. leaves in adult zebrafish (Danio rerio)

Ziziphus joazeiro Mart. is an endemic plant of the Caatinga that presents a great socioeconomic importance for the Northeast and Semiarid Region of Brazil. In view of this, this study aimed to evaluate the antibacterial activity and anxiolytic-like effects of Ziziphus joazeiro Mart leaves in adult zebrafish (Danio rerio). The characterization of the main classes of metabolites was performed through chemical reactions. The antibacterial and antibiotic potentiating activity was evaluated by broth microdilution assays. The 96 h acute toxicity, open field test and anxiety models test was evaluated in vivo on adult zebrafish. The results obtained in the phytochemical prospection evidenced the presence of flobabenic tannins, leucoanthocyanidins, flavonois, flavonones, catechins, alkaloids, steroids, and triterpenoids. EEFZJ did not show antibacterial activity for all microorganism tested (MIC ≥ 1024 µg/mL), but reduced the concentration required for bacterial growth inhibition in combination with gentamicin and norfloxacin against multidrug-resistant strains of S. aureus (SA10) and E. coli (EC06), exhibiting synergistic effect with these antibiotics (p<0.0001). In the tests in vivo, EEFZJ was found to be nontoxic, performing reduced locomotor activity and demonstrated an anxiolytic-like effect in adult zebrafish via GABAergic and Serotoninergic systems (5-HT1, 5-HT2A/2C and 5-HT3A/3B).

Antioxidant, Antimicrobial and Cosmeceutical Potential of Wild Mushroom Extracts

Macrofungi have been previously studied for their nutritional value and medicinal properties. However, despite wild mushrooms being a great source of beneficial bioactive compounds, the literature exploring their biotechnological application as nutraceuticals, cosmeceuticals and nutricosmetics is scarce. In this work, the species Butyriboletus regius, Ganoderma lucidum, Inonotus hispidus, Lanmaoa fragrans, Pisolithus tinctorius, Suillellus luridus, Suillellus mendax and Xerocomus subtomentosus were characterized according to their phenolic composition, antioxidant capacity, antimicrobial activity and cosmeceutical potential. For that purpose, dried and ground mushrooms were extracted with ethanol (40% v/v) using ultrasound-assisted extraction. Of the eight mushrooms analyzed, I. hispidus and P. tinctorius stood out for their high content of phenolic compounds, high antioxidant capacity and anti-hyaluronidase activity. Regarding antimicrobial activity, both mushrooms showed good inhibition of bacterial growth and bactericidal activity, especially on Gram-positive bacteria; however, L. fragans obtained the best results. Cream formulations with I. hispidus and P. tinctorius extracts in their composition improved their antioxidant activity. These results indicate that I. hispidus and P. tinctorius can be proposed as a new potential source of natural compounds with application in the cosmetic industry.

Antimicrobial peptide-loaded decellularized placental sponge as an excellent antibacterial skin substitute against XDR clinical isolates.

Post-wound infections have remained a serious threat to society and healthcare worldwide. Attempts are still being made to develop an ideal antibacterial wound dressing with high wound-healing potential and strong antibacterial activity against extensively drug-resistant bacteria (XDR). In this study, a biological-based sponge was made from decellularized human placenta (DPS) and then loaded with different concentrations (0, 16µg/mL, 32µg/mL, 64µg/mL) of an antimicrobial peptide (AMP, CM11) to optimize an ideal antibacterial wound dressing. The decellularization of DPS was confirmed by histological evaluations and DNA content assay. The DPS loaded with different contents of antimicrobial peptides (AMPs) showed uniform morphology under a scanning electron microscope (SEM) and cytobiocompatibility for human adipose tissue-derived mesenchymal stem cells. Antibacterial assays indicated that the DPS/AMPs had antibacterial behavior against both standard strain and XDR Acinetobacter baumannii in a dose-dependent manner, as DPS loaded with 64µg/mL showed the highest bacterial growth inhibition zone and elimination of bacteria under SEM than DPS alone and DPS loaded with 16µg/mL and 32µg/mL AMP concentrations. The subcutaneous implantation of all constructs in the animal model demonstrated no sign of acute immune system reaction and graft rejection, indicating in vivo biocompatibility of the scaffolds. Our findings suggest the DPS loaded with 64µg/mL as an excellent antibacterial skin substitute, and now promises to proceed with pre-clinical and clinical investigations.

A concise review of chewing gum as an anti-cariogenic agent.

Chewing gum has been endorsed as a caries preventive agent by the FDI World Dental Federation, the American Dental Association, and the European Food Safety Authority. This review discusses the mechanism and provides an update of the use of chewing gum for caries prevention. Chewing gum typically consists of a water-insoluble gum base, water-soluble added ingredients, and active ingredients. It can be classified as sugar-containing or sugar-free, as well as nonmedicated or medicated. Chewing gum prevents dental caries through a range of mechanisms, including the clearance of the oral cavity, neutralization of oral acidity, inhibition of cariogenic bacterial growth, remineralization of enamel, and reduction of appetite. Recent clinical studies have evaluated the efficacy of sugar-free chewing gum for caries prevention, with most demonstrating positive results, although some studies have reported contradictory outcomes. To achieve optimal caries prevention, it is generally recommended that individuals chew sugar-free gum for five minutes after meals, three times daily.