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1.
Appl Microbiol Biotechnol ; 106(23): 7711-7720, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-2148738

ABSTRACT

Microbe (including bacteria, fungi, and virus) infection in brains is associated with amyloid fibril deposit and neurodegeneration. Increasing findings suggest that amyloid proteins, like Abeta (Aß), are important innate immune effectors in preventing infections. In some previous studies, amyloid peptides have been linked to antimicrobial peptides due to their common mechanisms in membrane-disruption ability, while the other mechanisms of bactericidal protein aggregation and protein function knockdown are less discussed. Besides, another important function of amyloid peptides in pathogen agglutination is rarely illustrated. In this review, we summarized and divided the different roles and mechanisms of amyloid peptides against microbes in antimicrobial activity and microbe agglutination activity. Besides, the range of amyloids' antimicrobial spectrum, the effectiveness of amyloid peptide states (monomers, oligomers, and fibrils), and cytotoxicity are discussed. The good properties of amyloid peptides against microbes might provide implications for the development of novel antimicrobial drug. KEY POINTS: • Antimicrobial and/or microbial agglutination is a characteristic of amyloid peptides. • Various mechanisms of amyloid peptides against microbes are discovered recently. • Amyloid peptides might be developed into novel antimicrobial drugs.


Subject(s)
Amyloid , Anti-Infective Agents , Amyloid/chemistry , Amyloid/metabolism , Amyloid beta-Peptides/chemistry , Amyloid beta-Peptides/metabolism , Anti-Infective Agents/pharmacology , Amyloidogenic Proteins , Anti-Bacterial Agents , Agglutination
2.
J Mater Chem B ; 10(45): 9349-9368, 2022 Nov 23.
Article in English | MEDLINE | ID: covidwho-2117996

ABSTRACT

Undesirable adhesion of microbes such as bacteria, fungi and viruses onto surfaces affects many industries such as marine, food, textile, and healthcare. In particular in healthcare and food packaging, the effects of unwanted microbial contamination can be life-threatening. With the current global COVID-19 pandemic, interest in the development of surfaces with superior anti-viral and anti-bacterial activities has multiplied. Polymers carrying anti-microbial properties are extensively used to functionalize material surfaces to inactivate infection-causing and biocide-resistant microbes including COVID-19. This review aims to introduce the fabrication of polymer-based antimicrobial surfaces through physical and chemical modifications, followed by the discussion of the inactivation mechanisms of conventional biocidal agents and new-generation antimicrobial macromolecules in polymer-modified antimicrobial surfaces. The advanced applications of polymer-based antimicrobial surfaces on personal protective equipment against COVID-19, food packaging materials, biomedical devices, marine vessels and textiles are also summarized to express the research trend in academia and industry.


Subject(s)
Anti-Infective Agents , COVID-19 , Humans , Polymers/pharmacology , Polymers/chemistry , COVID-19/drug therapy , Pandemics , Anti-Infective Agents/pharmacology , Anti-Infective Agents/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Bacteria
3.
Food Funct ; 13(21): 11083-11096, 2022 Oct 31.
Article in English | MEDLINE | ID: covidwho-2069897

ABSTRACT

Otomycosis is a serious superficial mycotic infection of the outer ear canal caused by some pathogenic species of Candida and Aspergillus. The infection remains a challenge to clinicians owing to the incomplete efficacy of market-available antifungal agents and high recurrence rates. The Moringa oleifera leaf ethanol extract showed efficacy against Candida albicans SC5314, compared to Nystatin® as a reference with MIC values of 7 and 718.33 µg ml-1, respectively. The extract was mixed with lecithin and chitosan to give Moringa core/shell giant nanoparticles, with a good zeta potential (+59.2 mV), a suitable entrapment efficiency (61%) and an enhanced release reaching up to 90% at 8 h. Clinical isolates from oomycote patients were identified via DNA sequencing as Candida parapsilosis, Aspergillus niger and Aspergillus flavus, and the effect of the prepared nanoparticles was tested against them via disk diffusion assay to give inhibition zones of 75, 55 and 55 mm, compared to Nystatin® with 35, 25 and 20 mm, respectively. Interestingly, patients treated with the Moringa-loaded nanoparticles experienced improvement within 1 week with no recurrence for more than 3 months. To have some insight into the bioactive components in the Moringa extract, LC-HRMS-based identification has been employed which led to the annotation of 27 compounds. Subsequent comprehensive in silico investigation suggested some alkaloids to be responsible for the activity targeting the fungal 14-α-demethylase enzyme (CYP51B). Our study revealed that Moringa extract-loaded nanoparticles attained an enhanced antifungal efficacy compared to Nystatin® and therefore they can be employed against invasive and drug-resistant otomycotic infections.


Subject(s)
Anti-Infective Agents , Moringa oleifera , Nanoparticles , Otomycosis , Humans , Nystatin/pharmacology , Antifungal Agents/pharmacology , Anti-Infective Agents/pharmacology , Plant Extracts/pharmacology
4.
Viruses ; 14(10)2022 10 06.
Article in English | MEDLINE | ID: covidwho-2066557

ABSTRACT

INTRODUCTION: Aedes aegypti is the vector of several arboviruses such as dengue, Zika, and chikungunya. In 2015-16, Zika virus (ZIKV) had an outbreak in South America associated with prenatal microcephaly and Guillain-Barré syndrome. This mosquito's viral transmission is influenced by microbiota abundance and diversity and its interactions with the vector. The conditions of cocirculation of these three arboviruses, failure in vector control due to insecticide resistance, limitations in dengue management during the COVID-19 pandemic, and lack of effective treatment or vaccines make it necessary to identify changes in mosquito midgut bacterial composition and predict its functions through the infection. Its study is fundamental because it generates knowledge for surveillance of transmission and the risk of outbreaks of these diseases at the local level. METHODS: Midgut bacterial compositions of females of Colombian Ae. aegypti populations were analyzed using DADA2 Pipeline, and their functions were predicted with PICRUSt2 analysis. These analyses were done under the condition of natural ZIKV infection and resistance to lambda-cyhalothrin, alone and in combination. One-step RT-PCR determined the percentage of ZIKV-infected females. We also measured the susceptibility to the pyrethroid lambda-cyhalothrin and evaluated the presence of the V1016I mutation in the sodium channel gene. RESULTS: We found high ZIKV infection rates in Ae. aegypti females from Colombian rural municipalities with deficient water supply, such as Honda with 63.6%. In the face of natural infection with an arbovirus such as Zika, the diversity between an infective and non-infective form was significantly different. Bacteria associated with a state of infection with ZIKV and lambda-cyhalothrin resistance were detected, such as the genus Bacteroides, which was related to functions of pathogenicity, antimicrobial resistance, and bioremediation of insecticides. We hypothesize that it is a vehicle for virus entry, as it is in human intestinal infections. On the other hand, Bello, the only mosquito population classified as susceptible to lambda-cyhalothrin, was associated with bacteria related to mucin degradation functions in the intestine, belonging to the Lachnospiraceae family, with the genus Dorea being increased in ZIKV-infected females. The Serratia genus presented significantly decreased functions related to phenazine production, potentially associated with infection control, and control mechanism functions for host defense and quorum sensing. Additionally, Pseudomonas was the genus principally associated with functions of the degradation of insecticides related to tryptophan metabolism, ABC transporters with a two-component system, efflux pumps, and alginate synthesis. CONCLUSIONS: Microbiota composition may be modulated by ZIKV infection and insecticide resistance in Ae. aegypti Colombian populations. The condition of resistance to lambda-cyhalothrin could be inducing a phenome of dysbiosis in field Ae. aegypti affecting the transmission of arboviruses.


Subject(s)
Aedes , Anti-Infective Agents , Arboviruses , COVID-19 , Dengue , Insecticides , Pyrethrins , Zika Virus Infection , Zika Virus , Animals , Female , Humans , Zika Virus/genetics , Insecticide Resistance , Insecticides/pharmacology , Colombia/epidemiology , Pandemics , Tryptophan , Mosquito Vectors , Pyrethrins/pharmacology , Bacteria , Metabolic Networks and Pathways , Phenazines , Mucins , ATP-Binding Cassette Transporters , Anti-Infective Agents/pharmacology , Alginates
5.
Molecules ; 27(19)2022 Oct 05.
Article in English | MEDLINE | ID: covidwho-2066284

ABSTRACT

Three unique 5,6-seco-hexahydrodibenzopyrans (seco-HHDBP) machaeridiols A-C, reported previously from Machaerium Pers., have displayed potent activities against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecium, and E. faecalis (VRE). In order to enrich the pipeline of natural product-derived antimicrobial compounds, a series of novel machaeridiol-based analogs (1-17) were prepared by coupling stemofuran, pinosylvin, and resveratrol legends with monoterpene units R-(-)-α-phellandrene, (-)-p-mentha-2,8-diene-1-ol, and geraniol, and their inhibitory activities were profiled against MRSA ATCC 1708, VRE ATCC 700221, and cancer signaling pathways. Compounds 5 and 11 showed strong in vitro activities with MIC values of 2.5 µg/mL and 1.25 µg/mL against MRSA, respectively, and 2.50 µg/mL against VRE, while geranyl analog 14 was found to be moderately active (MIC 5 µg/mL). The reduction of the double bonds of the monoterpene unit of compound 5 resulted in 17, which had the same antibacterial potency (MIC 1.25 µg/mL and 2.50 µg/mL) as its parent, 5. Furthermore, a combination study between seco-HHDBP 17 and HHDBP machaeriol C displayed a synergistic effect with a fractional inhibitory concentrations (FIC) value of 0.5 against MRSA, showing a four-fold decrease in the MIC values of both 17 and machaeriol C, while no such effect was observed between vancomycin and 17. Compounds 11 and 17 were further tested in vivo against nosocomial MRSA at a single intranasal dose of 30 mg/kg in a murine model, and both compounds were not efficacious under these conditions. Finally, compounds 1-17 were profiled against a panel of luciferase genes that assessed the activity of complex cancer-related signaling pathways (i.e., transcription factors) using T98G glioblastoma multiforme cells. Among the compounds tested, the geranyl-substituted analog 14 exhibited strong inhibition against several signaling pathways, notably Smad, Myc, and Notch, with IC50 values of 2.17 µM, 1.86 µM, and 2.15 µM, respectively. In contrast, the anti-MRSA actives 5 and 17 were found to be inactive (IC50 > 20 µM) across the panel of these cancer-signaling pathways.


Subject(s)
Anti-Infective Agents , Biological Products , Methicillin-Resistant Staphylococcus aureus , Neoplasms , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/pharmacology , Biological Products/pharmacology , Luciferases , Mice , Microbial Sensitivity Tests , Monoterpenes/pharmacology , Resveratrol/pharmacology , Signal Transduction , Transcription Factors , Vancomycin/pharmacology
6.
Molecules ; 27(19)2022 Sep 29.
Article in English | MEDLINE | ID: covidwho-2066279

ABSTRACT

Antimicrobial resistance (AMR) is a major concern for the survival of mankind. COVID-19 accelerated another silent pandemic of AMR through the uncontrolled use of antibiotics and biocides. New generations of antimicrobial agents are needed to combat resistant pathogens. Crown ethers can be used as models for drug action because they are similar to antibiotics. Iodine is a well-known microbicide but is characterized by instability and short-term effectivity. Iodine can be stabilized in the form of polyiodides that have a rich topology but are dependent on their immediate surroundings. In addition, copper has been successfully used since the beginning of history as a biocidal agent. We, therefore, combined iodine and copper with the highly selective crown ether 1,4,7,10-tetraoxacyclododecane (12-crown-4). The morphology and composition of the new pentaiodide [Cu(12-crown-4)2]I5 was investigated. Its antimicrobial activities against a selection of 10 pathogens were studied. It was found that C. albicans WDCM 00054 is highly susceptible to [Cu(12-crown-4)2]I5. Additionally, the compound has good to intermediate antimicrobial activity against Gram-positive and Gram-negative bacilli. The chain-like pentaiodide structure is V-shaped and consists of iodine molecules with very short covalent bonds connected to triiodides by halogen bonding. The single crystal structure is arranged across the lattice fringes in the form of ribbons or honeycombs. The susceptibility of microorganisms towards polyiodides depends on polyiodide bonding patterns with halogen-, covalent-, and non-covalent bonding.


Subject(s)
Anti-Infective Agents , COVID-19 , Crown Ethers , Disinfectants , Iodine , Anti-Bacterial Agents , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Copper/chemistry , Crown Ethers/chemistry , Halogens , Humans , Iodides , Iodine/chemistry
7.
Chem Soc Rev ; 51(20): 8696-8755, 2022 Oct 17.
Article in English | MEDLINE | ID: covidwho-2050564

ABSTRACT

Antimicrobial resistance is directly responsible for more deaths per year than either HIV/AIDS or malaria and is predicted to incur a cumulative societal financial burden of at least $100 trillion between 2014 and 2050. Already heralded as one of the greatest threats to human health, the onset of the coronavirus pandemic has accelerated the prevalence of antimicrobial resistant bacterial infections due to factors including increased global antibiotic/antimicrobial use. Thus an urgent need for novel therapeutics to combat what some have termed the 'silent pandemic' is evident. This review acts as a repository of research and an overview of the novel therapeutic strategies being developed to overcome antimicrobial resistance, with a focus on self-assembling systems and nanoscale materials. The fundamental mechanisms of action, as well as the key advantages and disadvantages of each system are discussed, and attention is drawn to key examples within each field. As a result, this review provides a guide to the further design and development of antimicrobial systems, and outlines the interdisciplinary techniques required to translate this fundamental research towards the clinic.


Subject(s)
Anti-Bacterial Agents , Anti-Infective Agents , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Anti-Infective Agents/pharmacology , Anti-Infective Agents/therapeutic use , Bacteria , Humans
8.
Int J Mol Sci ; 23(19)2022 Sep 23.
Article in English | MEDLINE | ID: covidwho-2043772

ABSTRACT

Due to the prevailing existence of the COVID-19 pandemic, novel and practical strategies to combat pathogens are on the rise worldwide. It is estimated that, globally, around 10% of hospital patients will acquire at least one healthcare-associated infection. One of the novel strategies that has been developed is incorporating metallic particles into polymeric materials that neutralize infectious agents. Considering the broad-spectrum antimicrobial potency of some materials, the incorporation of metallic particles into the intended hybrid composite material could inherently add significant value to the final product. Therefore, this research aimed to investigate an antimicrobial polymeric PLA-based composite material enhanced with different microparticles (copper, aluminum, stainless steel, and bronze) for the antimicrobial properties of the hybrid composite. The prepared composite material samples produced with fused filament fabrication (FFF) 3D printing technology were tested for different time intervals to establish their antimicrobial activities. The results presented here depict that the sample prepared with 90% copper and 10% PLA showed the best antibacterial activity (99.5%) after just 20 min against different types of bacteria as compared to the other samples. The metallic-enriched PLA-based antibacterial sheets were remarkably effective against Staphylococcus aureus and Escherichia coli; therefore, they can be a good candidate for future biomedical, food packaging, tissue engineering, prosthetic material, textile industry, and other science and technology applications. Thus, antimicrobial sheets made from PLA mixed with metallic particles offer sustainable solutions for a wide range of applications where touching surfaces is a big concern.


Subject(s)
Anti-Infective Agents , COVID-19 , Aluminum , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/pharmacology , COVID-19/drug therapy , Copper , Escherichia coli , Humans , Pandemics , Polyesters , Polymers , Printing, Three-Dimensional , Stainless Steel
10.
ACS Appl Mater Interfaces ; 14(37): 42483-42493, 2022 Sep 21.
Article in English | MEDLINE | ID: covidwho-2016531

ABSTRACT

Microbial adhesion and contamination on shared surfaces can lead to life-threatening infections with serious impacts on public health, economy, and clinical practices. The traditional use of chemical disinfectants for sanitization of surfaces, however, comes with its share of health risks, such as hazardous effects on the eyes, skin, and respiratory tract, carcinogenicity, as well as environmental toxicity. To address this, we have developed a nonleaching quaternary small molecule (QSM)-based sprayable coating which can be fabricated on a wide range of surfaces such as nylon, polyethylene, surgical mask, paper, acrylate, and rubber in a one-step, photocuring technique. This contact-active coating killed pathogenic bacteria and fungi including drug-resistant strains of Staphylococcus aureus and Candida albicans within 15-30 min of contact. QSM coatings withstood multiple washes, highlighting their durability. Interestingly, the coated surfaces exhibited rapid killing of pathogens, leading to the prevention of their transmission upon contact. The coating showed membrane disruption of bacterial cells in fluorescence and electron microscopic investigations. Along with bacteria and fungi, QSM-coated surfaces also showed the complete killing of high loads of influenza (H1N1) and SARS-CoV-2 viruses within 30 min of exposure. To our knowledge, this is the first report of a coating for multipurpose materials applied in high-touch public places, hospital equipment, and clinical consumables, rapidly killing drug-resistant bacteria, fungi, influenza virus, and SARS-CoV-2.


Subject(s)
Anti-Infective Agents , COVID-19 , Disinfectants , Influenza A Virus, H1N1 Subtype , Influenza, Human , Acrylates/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Infective Agents/pharmacology , Bacteria , COVID-19/prevention & control , Disinfectants/pharmacology , Fungi , Humans , Nylons/pharmacology , Polyethylenes/pharmacology , Rubber , SARS-CoV-2
11.
Colloids Surf B Biointerfaces ; 217: 112693, 2022 Sep.
Article in English | MEDLINE | ID: covidwho-2015062

ABSTRACT

Coronavirus pandemic has evidenced the importance of creating bioactive materials to mitigate viral infections, especially in healthcare settings and public places. Advances in antiviral coatings have led to materials with impressive antiviral performance; however, their application may face health and environmental challenges. Bio-inspired antimicrobial peptides (AMPs) are suitable building blocks for antimicrobial coatings due to their versatile design, scalability, and environmentally friendly features. This review presents the advances and opportunities on the AMPs to create virucidal coatings. The review first describes the fundamental characteristics of peptide structure and synthesis, highlighting the recent findings on AMPs and the role of peptide structure (α-helix, ß-sheet, random, and cyclic peptides) on the virucidal mechanism. The following section presents the advances in AMPs coating on medical devices with a detailed description of the materials coated and the targeted pathogens. The use of peptides in vaccine formulations is also reported, emphasizing the molecular interaction of peptides with different viruses and the current clinical stage of each formulation. The role of several materials (metallic particles, inorganic materials, and synthetic polymers) in the design of antiviral coatings is also presented, discussing the advantages and the drawbacks of each material. The final section offers future directions and opportunities for using AMPs on antiviral coatings to prevent viral outbreaks.


Subject(s)
Anti-Infective Agents , Viruses , Anti-Bacterial Agents , Anti-Infective Agents/pharmacology , Antimicrobial Cationic Peptides/chemistry , Antimicrobial Cationic Peptides/pharmacology , Antimicrobial Peptides , Antiviral Agents/pharmacology
12.
Bioprocess Biosyst Eng ; 45(9): 1421-1445, 2022 Sep.
Article in English | MEDLINE | ID: covidwho-2014147

ABSTRACT

Rapid transmission of infectious microorganisms such as viruses and bacteria through person-to-person contact has contributed significantly to global health issues. The high survivability of these microorganisms on the material surface enumerates their transmissibility to the susceptible patient. The antimicrobial coating has emerged as one of the most interesting technologies to prevent growth and subsequently kill disease-causing microorganisms. It offers an effective solution a non-invasive, low-cost, easy-in-use, side-effect-free, and environmentally friendly method to prevent nosocomial infection. Among antimicrobial coating, zinc oxide (ZnO) stands as one of the excellent materials owing to zero toxicity, high biocompatibility to human organs, good stability, high abundancy, affordability, and high photocatalytic performance to kill various infectious pathogens. Therefore, this review provides the latest research progress on advanced applications of ZnO nanostructure-based antibacterial coatings for medical devices, biomedical applications, and health care facilities. Finally, future challenges and clinical practices of ZnO-based antibacterial coating are addressed.


Subject(s)
Anti-Infective Agents , Zinc Oxide , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/pharmacology , Humans , Zinc Oxide/pharmacology
13.
J Appl Microbiol ; 133(6): 3347-3367, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-2008746

ABSTRACT

Betalains are nitrogen-containing plant pigments that can be red-violet (betacyanins) or yellow-orange (betaxanthins), currently employed as natural colourants in the food and cosmetic sectors. Betalains exhibit antimicrobial activity against a broad spectrum of microbes including multidrug-resistant bacteria, as well as single-species and dual-species biofilm-producing bacteria, which is highly significant given the current antimicrobial resistance issue reported by The World Health Organization. Research demonstrating antiviral activity against dengue virus, in silico studies including SARS-CoV-2, and anti-fungal effects of betalains highlight the diversity of their antimicrobial properties. Though limited in vivo studies have been conducted, antimalarial and anti-infective activities of betacyanin have been observed in living infection models. Cellular mechanisms of antimicrobial activity of betalains are yet unknown; however existing research has laid the framework for a potentially novel antimicrobial agent. This review covers an overview of betalains as antimicrobial agents and discussions to fully exploit their potential as therapeutic agents to treat infectious diseases.


Subject(s)
Anti-Infective Agents , COVID-19 , Humans , Betalains/pharmacology , Betalains/therapeutic use , SARS-CoV-2 , COVID-19/drug therapy , Betacyanins , Anti-Infective Agents/pharmacology , Anti-Infective Agents/therapeutic use
14.
Sci Rep ; 12(1): 14438, 2022 08 24.
Article in English | MEDLINE | ID: covidwho-2000930

ABSTRACT

The lack of therapeutic options to fight Covid-19 has contributed to the current global pandemic. Despite the emergence of effective vaccines, development of broad-spectrum antiviral treatment remains a significant challenge, in which antimicrobial photodynamic therapy (aPDT) may play a role, especially at early stages of infection. aPDT of the nares with methylene blue (MB) and non-thermal light has been successfully utilized to inactivate both bacterial and viral pathogens in the perioperative setting. Here, we investigated the effect of MB-aPDT to inactivate human betacoronavirus OC43 and SARS-CoV-2 in vitro and in a proof-of-principle COVID-19 clinical trial to test, in a variety of settings, the practicality, technical feasibility, and short-term efficacy of the method. aPDT yielded inactivation of up to 6-Logs in vitro, as measured by RT-qPCR and infectivity assay. From a photo-physics perspective, the in vitro results suggest that the response is not dependent on the virus itself, motivating potential use of aPDT for local destruction of SARS-CoV-2 and its variants. In the clinical trial we observed variable effects on viral RNA in nasal-swab samples as assessed by RT-qPCR attributed to aPDT-induced RNA fragmentation causing falsely-elevated counts. However, the viral infectivity in clinical nares swabs was reduced in 90% of samples and undetectable in 70% of samples. This is the first demonstration based on quantitative clinical viral infectivity measurements that MB-aPDT is a safe, easily delivered and effective front-line technique that can reduce local SARS-CoV-2 viral load.


Subject(s)
COVID-19 , Disinfection , Nose , Photochemotherapy , Anti-Infective Agents/adverse effects , Anti-Infective Agents/pharmacology , COVID-19/drug therapy , Disinfection/methods , Feasibility Studies , Humans , Methylene Blue/adverse effects , Methylene Blue/pharmacology , Nose/virology , Pandemics , RNA, Viral/analysis , SARS-CoV-2/drug effects , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Treatment Outcome , Viral Load/drug effects
15.
Molecules ; 27(15)2022 Aug 05.
Article in English | MEDLINE | ID: covidwho-1994118

ABSTRACT

The aim of this study was to determine the variability of several chemical compounds and the antioxidant and antimicrobial activities of eight types of berries harvested from two different geographical regions in the same year. The analyses were performed on bilberry, black currant, gooseberry, red currant, raspberry, sea buckthorn, strawberry and sour cherry, which were handpicked during the summer of 2019, in the same periods when they are typically harvested for consumer purposes. Total anthocyanins content (TAC), total flavonoids content (TFC), total polyphenolic compounds (TPC), determination of the Ferric-Reducing Antioxidant Power (FRAP), determination of the DPPH free radical scavenging assay (RSA), determination of nine phenolic compounds by HPLC-UV assay and antimicrobial activity were determined for undiluted hydroalcoholic extracts of all the studied berries. The results showed that the berries from Romania were richer in antioxidant compounds than the berries from Russia. The TPC content varied between 4.13-22.2 mg GAE/g d.w., TFC between 3.33-8.87 mg QE/g d.w. and TAC between 0.13-3.94 mg/g d.w. The highest variability was determined for TPC. Regarding the antioxidant activity assessed by FRAP assay, values were between 6.02-57.23 µmols TE/g d.w. and values for the RSA method between 18.44-83.81%. From the eight types of berries analyzed, bilberries and raspberries had the highest antioxidant activity considering both regions and both determination methods. Not only the type, but also the environmental and cultivation conditions in which the berries grow, can lead to variations in their chemical composition. The extracted polyphenolic compounds from the studied berries showed antibacterial properties on pathogens, such as Escherichia coli, Bacillus subtilis and Staphyloccocus aureus. The inhibitory action on Salmonella typhi and fungi Candida albicans and Aspegillus niger was absent to very low. The antimicrobial activity of the hydroalcoholic extracts was dependent on the provenance of the berries, too.


Subject(s)
Anti-Infective Agents , Ribes , Vaccinium myrtillus , Anthocyanins/analysis , Anthocyanins/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/analysis , Anti-Infective Agents/pharmacology , Antioxidants/chemistry , Flavonoids/analysis , Flavonoids/pharmacology , Fruit/chemistry , Phytochemicals/analysis , Phytochemicals/pharmacology , Plant Extracts/chemistry , Ribes/chemistry
16.
Molecules ; 27(15)2022 Jul 26.
Article in English | MEDLINE | ID: covidwho-1994113

ABSTRACT

Some new N- and C-modified biomolecular peptide analogues of both VV-hemorphin-5 and VV-hemorphin-7 with varied amino acids (Cys, Glu, His), 1-adamantanecarboxylic acid, and niacin (nicotinic acid) were synthesized by solid-phase peptide synthesis-Fmoc (9-fluorenylmethoxy-carbonyl) chemistry and were characterized in water solutions with different pH using spectroscopic and electrochemical techniques. Basic physicochemical properties related to the elucidation of the peptide structure at physiological pH have been also studied. The results showed that the interaction of peptide compounds with light and electricity preserves the structural and conformational integrity of the compounds in the solutions. Moreover, textile cotton fibers were modified with the new compounds and the binding of the peptides to the surface of the material was proved by FTIR and SEM analysis. Washing the material with an alkaline soap solution did not show a violation of the modified structure of the cotton. Antiviral activity against the human respiratory syncytial virus (HRSV-S2) and human adenovirus serotype 5 (HAdV-5), the antimicrobial activity against B. cereus and P. aeruginosa used as model bacterial strains and cytotoxic effect of the peptide derivatives and modified cotton textile material has been evaluated. Antimicrobial tests showed promising activity of the newly synthesized compounds against the used Gram-positive and Gram-negative bacteria. The compounds C-V, H-V, AC-V, and AH-V were found slightly more active than NH7C and NCH7. The activity has been retained after the deposition of the compounds on cotton fibers.


Subject(s)
Anti-Infective Agents , Gram-Negative Bacteria , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Cotton Fiber , Gram-Positive Bacteria , Humans , Textiles
17.
J Nanobiotechnology ; 20(1): 375, 2022 Aug 12.
Article in English | MEDLINE | ID: covidwho-1993365

ABSTRACT

Given the spasmodic increment in antimicrobial resistance (AMR), world is on the verge of "post-antibiotic era". It is anticipated that current SARS-CoV2 pandemic would worsen the situation in future, mainly due to the lack of new/next generation of antimicrobials. In this context, nanoscale materials with antimicrobial potential have a great promise to treat deadly pathogens. These functional materials are uniquely positioned to effectively interfere with the bacterial systems and augment biofilm penetration. Most importantly, the core substance, surface chemistry, shape, and size of nanomaterials define their efficacy while avoiding the development of AMR. Here, we review the mechanisms of AMR and emerging applications of nanoscale functional materials as an excellent substitute for conventional antibiotics. We discuss the potential, promises, challenges and prospects of nanobiotics to combat AMR.


Subject(s)
Anti-Infective Agents , COVID-19 , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Anti-Infective Agents/pharmacology , COVID-19/drug therapy , Drug Resistance, Bacterial , Humans , RNA, Viral , SARS-CoV-2
19.
Commun Biol ; 5(1): 647, 2022 07 04.
Article in English | MEDLINE | ID: covidwho-1972668

ABSTRACT

The continuous emergence of microbial pathogens for which there are no effective antimicrobials threatens global health, necessitating novel antimicrobial approaches. Here, we present a targeted antimicrobial strategy that can be applied to various microbial pathogens. A photoimmuno-conjugate composed of an antibody against the target pathogen and a photoplastic phthalocyanine-derivative probe that generates photo-induced mechanical stress was developed based on photoimmuno-technology. This strategy, named as photoimmuno-antimicrobial strategy (PIAS), eliminates targeted pathogens, regardless of the target species or drug-resistance status. Specifically, PIAS acts on a broad range of microbes, including the bacterial pathogen Staphylococcus aureus, fungal pathogen Candida albicans, including their drug-resistant strains, and viral pathogen SARS-CoV-2, the causative agent of COVID-19. Furthermore, PIAS protects mice from fatal infections without damaging the non-targeted host microbiota and tissues. This study may contribute to the development of next-generation anti-infective therapies.


Subject(s)
Anti-Infective Agents , COVID-19 , Animals , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/pharmacology , Bacteria , COVID-19/drug therapy , Mice , SARS-CoV-2
20.
Arch Microbiol ; 204(8): 535, 2022 Jul 30.
Article in English | MEDLINE | ID: covidwho-1971673

ABSTRACT

Clioquinol and nitroxoline, two drugs with numerous pharmacological properties fallen into disuse for many decades. The first was considered dangerous due to contraindications and the second mainly because was taken as ineffective, despite its known antibacterial activity. In the last decades, the advances in pharmaceutical chemistry, molecular biology, toxicology and genetics allowed to better understand the cellular action of these compounds, some toxicological issues and/or activity scopes. Thus, a new opportunity for these drugs to be considered as potential antimicrobial agents has arisen. This review contemplates the trajectory of clioquinol and nitroxoline from their emergence to the present day, emphasizing the new studies that indicate the possibility of reintroduction for specific cases.


Subject(s)
Anti-Infective Agents , Clioquinol , Nitroquinolines , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/pharmacology , Clioquinol/pharmacology , Nitroquinolines/pharmacology
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