Effectiveness of plant-based hand sanitizer incorporating Quercus infectoria gall extract.

AIMS: Quercus infectoria (Qi), a traditional herbal plant with a broad spectrum of activities on multidrug-resistant bacteria, has been developed for hand sanitizer applications. METHODS AND RESULTS: Antimicrobial activity was evaluated using agar-well diffusion and broth microdilution method. Bactericidal activity was determined following the European Standard 1276 antibacterial suspension test. Neutralization assay was performed to assess antirespiratory syncytial virus. Safety, stability, and skin permeation of Qi hand gel was investigated. Qi hand sanitizer gel inhibited microorganisms ranging from 99.9% to 99.999% against Enterococcus faecalis, Staphylococcus aureus, methicillin-resistant Staph. aureus, Staph. epidermidis, Staph. pseudintermedius, Staph. saprophyticus, Streptococcus pyogenes, Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Candida albicans. A significant reduction in main human dermatophytes including Microsporum canis, M. gypseum, and Talaromyces marneffei of ∼50% was observed (P < .05). Qi hand sanitizer gel inactivated >99% viral particles entering human laryngeal epidermoid carcinoma cells in a dose-dependent manner. Scanning electron micrographs further illustrated that Qi hand sanitizer gel disrupted microbial cell membrane after 1-min contact time resulting in cell death. Qi hand sanitizer gel delivered emollient compounds through simulated human skin layers and showed no cytotoxicity on fibroblast cells. Moreover, Qi hand sanitizer gel demonstrated stability under extreme conditions. CONCLUSIONS: Qi hand sanitizer gel was able to inhibit various microorganisms including bacteria, dermatophytes, and virus.

Eucalyptus-Mediated Synthesized Silver Nanoparticles-Coated Urinary Catheter Inhibits Microbial Migration and Biofilm Formation.

Catheter-associated urinary tract infections (CAUTIs) are significant complications among catheterized patients, resulting in increased morbidity, mortality rates, and healthcare costs. Foley urinary catheters coated with synthesized silver nanoparticles (AgNPs) using Eucalyptus camaldulensis leaf extract were developed using a green chemistry principle. In situ-deposited AgNPs with particle size ranging between 20 and 120 nm on the catheter surface were illustrated by scanning electron microscopy. Atomic force microscopy revealed the changes in surface roughness after coating with nanoparticles. The coated catheter could significantly inhibit microbial adhesion and biofilm formation performed in pooled human urine-supplemented media to mimic a microenvironment during infections (p 0.05). AgNPs-coated catheter exhibited broad-spectrum antimicrobial activity against important pathogens, causing CAUTIs with no cytotoxic effects on HeLa cells. A reduction in microbial viability in biofilms was observed under confocal laser scanning microscopy. A catheter bridge model demonstrated complete prevention of Proteus mirabilis migration by the coated catheter. Significant inhibition of ascending motility of Escherichia coli and P. mirabilis along the AgNPs-coated catheter was demonstrated in an in vitro bladder model (p 0.05). The results suggested that the AgNPs-coated urinary catheter could be applied as an alternative strategy to minimize the risk of CAUTIs by preventing bacterial colonization and biofilm formation.

New acylphloroglucinols from a crude acetone extract of Eucalyptus camaldulensis Dehnh. leaf.

Acylphloroglucinols are well-known Eucalyptus secondary metabolites which exhibit a variety of structures and bioactivities. The investigation of a crude acetone extract of Eucalyptus camaldulensis leaves led to the isolation of two new acylphloroglucinols, eucalypcamals O and P (1 and 2) together with seven phloroglucinols (3-9), and a benzene derivative (10). Their chemical structures were elucidated by 1D and 2D nuclear magnetic resonance (NMR) spectroscopy and mass spectroscopy. The absolute configurations of compounds 1 and 2 were established by comparison of experimental and calculated electronic circular dichroism (ECD) data. In the putative biosynthetic pathway, eucalypcamals O and P should be derived from hetero-Diels-Alder reaction between grandinol and trans-isoeugenol.

Poly (vinyl alcohol) copolymerized with xanthan gum/hypromellose/sodium carboxymethyl cellulose dermal dressings functionalized with biogenic nanostructured materials for antibacterial and wound healing application.

Effective treatment of infected wounds requires a comprehensive wound dressing with a combination of antibacterial, antioxidative, and anti-inflammatory effects. Biodegradable wound dressings incorporating nanostructured material were developed using polyvinyl alcohol with xanthan gum, hypromellose, or sodium carboxymethyl cellulose and extensively evaluated for antibacterial and wound healing efficacy. Synthesized silver nanoparticles and wound dressings displayed λmax at 420 nm with zeta potential ≈ - 35 mV. Significant growth inhibition with >99 % reduction in CFU/ml (p < 0.05) against important wound pathogens including Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, and Candida albicans were observed. Within 1 h of treatment, hypromellose nanocomposite demonstrated excellent bactericidal effects with a 99.9 % of reduction in growth. In addition, wound dressings demonstrated inhibitory activities against free radical scavengers. Wound dressings demonstrated a significant reduction in the inflammatory response in RAW 264.7 macrophages (p < 0.001). Ex-vivo diffusion demonstrated zero-order release and steady-state flux between 0.1571-0.2295 µg/ml/cm2h with 0.124-0.144 permeability coefficient after 10 h. Usage in animals further confirmed that the hypromellose nanocomposite accelerated the wound healing process with biocompatibility. The results suggested that hybrid biodegradable dressings can be effectively applied to treat infected wounds and attenuate inflammatory responses.