Characterizations and Antibacterial Efficacy of Chitosan Oligomers Synthesized by Microwave-Assisted Hydrogen Peroxide Oxidative Depolymerization Method for Infectious Wound Applications

The use of naturally occurring materials with antibacterial properties has gained a great interest in infected wound management. Despite being an abundant resource in Vietnam, chitosan and its derivatives have not yet been intensively explored for their potential in such application. Here, we utilized a local chitosan source to synthesize chitosan oligomers (OCS) using hydrogen peroxide (H2O2) oxidation under the microwave irradiation method. The effects of H2O2 concentration on the physicochemical properties of OCS were investigated through molecular weight, degree of deacetylation, and heavy metal contamination for optimization of OCS formulation. Then, the antibacterial inhibition was examined; the minimum inhibitory concentration and minimum bactericidal concentration (MIC and MBC) of OCS-based materials were determined against common skin-inhabitant pathogens. The results show that the local Vietnamese chitosan and its derivative OCS possessed high-yield purification while the molecular weight of OCS was inversely proportional and proportional to the concentration of H2O2, respectively. Further, the MIC and MBC of OCS ranged from 3.75 to less than 15 mg/mL and 7.5–15 mg/mL, respectively. Thus, OCS-based materials induce excellent antimicrobial properties and can be attractive for wound dressings and require further investigation.

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Characterization, Antimicrobial Properties and Coatings Application of Gellan Gum Oxidized with Hydrogen Peroxide

Foods ◽

10.3390/foods8010031 ◽

2019 ◽

Vol 8 (1) ◽

pp. 31 ◽

Cited By ~ 4

Author(s):

Yushuang Lu ◽

Xiaojian Zhao ◽

Sheng Fang

Keyword(s):

Hydrogen Peroxide ◽

1H Nmr Spectroscopy ◽

Antimicrobial Properties ◽

Antimicrobial Activities ◽

Gellan Gum ◽

Proton Nuclear Magnetic Resonance ◽

Carboxyl Groups ◽

Gram Negative Bacteria ◽

Gram Positive Bacteria ◽

H2o2 Oxidation

The effect of hydrogen peroxide (H2O2) oxidation on the physicochemical, gelation and antimicrobial properties of gellan gum was studied. The oxidized gellan gum (OGG) was characterized by measuring the carboxyl/carbonyl group contents, Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. The H2O2 oxidation resulted in a large increase in the carboxyl groups in gellan gum. The OGG lost gelation ability by oxidation even in the presence of metal ions. The antimicrobial activities of the OGG against Gram-positive bacteria (Staphylococcus aureus), Gram-negative bacteria (Escherichia coli), and fungal (Aspergillus niger) were tested. The OGG could inhibit the growth of both bacteria and fungal, and the activity was improved with an increase in the oxidation level. Finally, the application of the OGG as an active coatings material to extend the storage of apples was tested.

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In vitro studies of antibacterial and antifungal wound dressings comprising H2TiO3 and SiO2 nanoparticles

Polish Journal of Microbiology ◽

10.33073/pjm-2015-020 ◽

2015 ◽

Vol 64 (2) ◽

pp. 137-142 ◽

Cited By ~ 4

Author(s):

LUKASZ KROKOWICZ ◽

HANNA TOMCZAK ◽

ADAM BOBKIEWICZ ◽

JACEK MACKIEWICZ ◽

RYSZARD MARCINIAK ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Adult Population ◽

Antimicrobial Properties ◽

Wound Dressings ◽

Wound Management ◽

Current Standard ◽

Silicon Dioxide Nanoparticles ◽

Complex Wound ◽

Zones Of Inhibition

The incidence rate of the infected and complex wound is established at approximately 40,000/1 million of the world's adult population. The aim of this study was to assess the efficiency of three novel types of wound dressings comprising sodium chloride, metatitanic acid and silicon dioxide nanoparticles. The study design was to prove their antimicrobial properties against the microorganisms most commonly causing wound infections. The study evaluated the antimicrobial effect of tested dressings on referenced strains of bacteria (ATCC collection, Argenta, Poland) and strains of fungi species (our own collection of fungi cultured from patients). The dressings were tested with both bacterial and fungal strains on solid media (Mueller-Hinton, Sobouraud, bioMerieux, France) in the standard method. The results confirmed the inhibition of growth of bacteria and revealed zones of inhibition for Escherichia coli, Staphylococcus aureus and Enterococcus faecalis. Significant zones of inhibition were established for Staphylococcus aureus and for fungi species of the Candida sp. These results would be crucial due to the fact of the low availability of antifungal therapeutics for both systemic and topical usage. Moreover, the current standard of antifungal treatment is associated with high costs and high toxicity in general. The preliminary results are very promising but further studies are necessary. Based on the obtained results, the tested dressings may contribute to the development of the surgical armamentarium of complex wound management in the near future.

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Bacteriocins of lactic acid bacteria and their application on food as biopreservatives. (II)

Journal of the Hellenic Veterinary Medical Society ◽

10.12681/jhvms.15221 ◽

2017 ◽

Vol 54 (1) ◽

pp. 69

Author(s):

J. METAXOPOULOS (Ι. ΜΕΤΑΞΟΠΟΥΛΟΣ) ◽

M. MATARAGAS (M. ΜΑΤΑΡΑΓΚΑΣ) ◽

E. H. DROSINOS (Ε.Χ. ΔΡΟΣΙΝΟΣ)

Keyword(s):

Carbon Dioxide ◽

Hydrogen Peroxide ◽

Molecular Weight ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Pathogenic Bacteria ◽

Antimicrobial Properties ◽

Small Molecular Weight ◽

Inhibitory Spectrum ◽

Protective Cultures

Lactic acid bacteria produce a variety of small molecular weight compounds, which have antimicrobial properties. Such substances are: organic acids, alcohols, carbon dioxide, diacetyl, hydrogen peroxide and bacteriocins. Many of these compounds have a wide inhibitory spectrum but the bacteriocins are able to inhibit species, namely, related with the bacteriocin-producing strain. In the last years bacteriocins have gained a lot of concern because some of them are able to inhibit the growth of pathogenic bacteria, like Listeria monocytogenes. The term "biopreservation" refers to the extension of storage life, as well as to the enhancement of the food safety, using the bacteriocin-producing lactic acid strains or their metabolic antibacterial products. In this review will be reported bacteriocins, which are produced by the lactic acid bacteria and will be discussed the potential application of the bacteriocinogenic strains or their bacteriocins on the foods, as protective cultures or as protective compounds, respectively.

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Preparation of high-molecular-weight poly(vinyl alcohol) with high yield by solution polymerization of vinyl acetate in methanol using 4,4′-azobis(4-cyanovaleric acid)

Journal of Applied Polymer Science ◽

10.1002/app.24737 ◽

2006 ◽

Vol 102 (5) ◽

pp. 4831-4834 ◽

Cited By ~ 1

Author(s):

Won S. Lyoo ◽

Du H. Song ◽

Won C. Lee ◽

Sung S. Han ◽

Seok K. Noh

Keyword(s):

Molecular Weight ◽

High Molecular Weight ◽

Vinyl Acetate ◽

Vinyl Alcohol ◽

High Yield ◽

Poly Vinyl Alcohol ◽

Solution Polymerization ◽

High Molecular Weight Poly

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Fast one-step synthesis of N-doped carbon dots by pyrolyzing ethanolamine

Journal of Materials Chemistry C ◽

10.1039/c4tc01139b ◽

2014 ◽

Vol 2 (36) ◽

pp. 7477-7481 ◽

Cited By ~ 99

Author(s):

Xinwei Dong ◽

Yanjie Su ◽

Huijuan Geng ◽

Zhongli Li ◽

Chao Yang ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Carbon Dots ◽

High Yield ◽

One Step ◽

Doped Carbon Dots

N-doped CDs can be obtained directly with high yield by pyrolyzing ethanolamine in air within just 7 minutes with the assistance of hydrogen peroxide.

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The effect of hydrogen peroxide bleaching of canola meal on product colour, dry matter and protein extractability and molecular weight profile

International Journal of Food Science & Technology ◽

10.1111/ijfs.12065 ◽

2013 ◽

Vol 48 (5) ◽

pp. 1071-1085 ◽

Cited By ~ 3

Author(s):

Ihsane El-Kadiri ◽

Mohamed Khelifi ◽

Mohammed Aider

Keyword(s):

Hydrogen Peroxide ◽

Molecular Weight ◽

Dry Matter ◽

Canola Meal ◽

Peroxide Bleaching ◽

Protein Extractability

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Polymer-Based Scaffolds Loaded with Aloe vera Extract for the Treatment of Wounds

Pharmaceutics ◽

10.3390/pharmaceutics13070961 ◽

2021 ◽

Vol 13 (7) ◽

pp. 961

Author(s):

Sibusiso Alven ◽

Vuyolwethu Khwaza ◽

Opeoluwa O. Oyedeji ◽

Blessing A. Aderibigbe

Keyword(s):

Wound Healing ◽

Chronic Wounds ◽

Mechanical Performance ◽

Healing Process ◽

Aloe Vera ◽

Antimicrobial Properties ◽

Biological Properties ◽

Wound Management ◽

Wound Healing Process ◽

Treatment Of Wounds

The treatment of wounds is one challenging biomedical field due to delayed wound healing common in chronic wounds. Several factors delay wound healing, including microbial infections, malnutrition, underlying physiological conditions, etc. Most of the currently used wound dressing materials suffer from poor antimicrobial properties, poor biodegradability and biocompatibility, and weak mechanical performance. Plant extracts, such as Aloe vera, have attracted significant attention in wound management because of their interesting biological properties. Aloe vera is composed of essential constituents beneficial for the wound healing process, such as amino acids, vitamins C and E, and zinc. Aloe vera influences numerous factors that are involved in wound healing and stimulates accelerated healing. This review reports the therapeutic outcomes of aloe vera extract-loaded polymer-based scaffolds in wound management.

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EP.TU.854Happy Patients and Updated Open Wound Management Protocols

British Journal of Surgery ◽

10.1093/bjs/znab311.108 ◽

2021 ◽

Vol 108 (Supplement_7) ◽

Author(s):

Harish Peri ◽

Rafique Umer Harvitkar

Keyword(s):

Chronic Wound ◽

Clinical Audit ◽

Wound Dressings ◽

Wound Management ◽

Open Wound ◽

Current Management ◽

Pdsa Cycle ◽

Management Protocol ◽

Open Injuries

Abstract Introduction Open injuries have a potential for serious bacterial wound infections and may lead to long term disabilities, chronic wound or bone infection, and even death. This QI study was undertaken to ring in changes to the current management protocol and align them as per WHO guidelines. Method Implementing changes through a Plan-Do-Study-Act (PDSA) cycle post an initial clinical audit among 38 patients of the organization. Re-audits were done to measure the outcome against the standard and establish a new protocol. Results Initial audit showed only a dismal 37% (n = 14) of patients being managed as per WHO protocol. Patient satisfaction percentage (as measured by a questionnaire) was also low with only 54% of patients satisfied with the treatment. Significant variations were noted post implementation of changes after the first PDSA cycle where >90% (n = 35) of patients reported that they noticed better wound healing, transition to optimal performance and were satisfied with treatment outcomes. Conclusions Timely wound dressings, appropriate antibiotic prophylaxis and increased patient’s awareness on wound hygiene through means of regular educational sessions and updated management protocols have led to healthier patients, lesser long term disabilities and happy patients.

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Novel Antioxidant Properties of Doxycycline

International Journal of Molecular Sciences ◽

10.3390/ijms19124078 ◽

2018 ◽

Vol 19 (12) ◽

pp. 4078 ◽

Cited By ~ 9

Author(s):

Dahn Clemens ◽

Michael Duryee ◽

Cleofes Sarmiento ◽

Andrew Chiou ◽

Jacob McGowan ◽

...

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Hydrogen Peroxide ◽

Chronic Inflammation ◽

Antioxidant Properties ◽

Antibacterial Properties ◽

Reactive Oxygen ◽

Protein Adducts ◽

Oxygen Species ◽

Free System

Doxycycline (DOX), a derivative of tetracycline, is a broad-spectrum antibiotic that exhibits a number of therapeutic activities in addition to its antibacterial properties. For example, DOX has been used in the management of a number of diseases characterized by chronic inflammation. One potential mechanism by which DOX inhibits the progression of these diseases is by reducing oxidative stress, thereby inhibiting subsequent lipid peroxidation and inflammatory responses. Herein, we tested the hypothesis that DOX directly scavenges reactive oxygen species (ROS) and inhibits the formation of redox-mediated malondialdehyde-acetaldehyde (MAA) protein adducts. Using a cell-free system, we demonstrated that DOX scavenged reactive oxygen species (ROS) produced during the formation of MAA-adducts and inhibits the formation of MAA-protein adducts. To determine whether DOX scavenges specific ROS, we examined the ability of DOX to directly scavenge superoxide and hydrogen peroxide. Using electron paramagnetic resonance (EPR) spectroscopy, we found that DOX directly scavenged superoxide, but not hydrogen peroxide. Additionally, we found that DOX inhibits MAA-induced activation of Nrf2, a redox-sensitive transcription factor. Together, these findings demonstrate the under-recognized direct antioxidant property of DOX that may help to explain its therapeutic potential in the treatment of conditions characterized by chronic inflammation and increased oxidative stress.

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