Biological activity of silver nanoparticles synthesized using viticultural waste.

This research paper presents a novel approach to the green synthesis of silver nanoparticles (AgNPs) using viticultural waste, allowing to obtain NP dispersions with distinct properties and morphologies (monodisperse and polydisperse AgNPs, referred to as mAgNPs and pAgNPs) and to compare their biological activities. Our synthesis method utilized the ethanolic extract of Vitis vinifera pruning residues, resulting in the production of mAgNPs and pAgNPs with average sizes of 12 ± 5 nm and 19 ± 14 nm, respectively. Both these AgNPs preparations demonstrated an exceptional stability in terms of size distribution, which was maintained for one year.

Bimetallic nanoparticle production using and waste extracts.

The utilization of waste materials for the synthesis of nanoparticles has gained significant attention due to its potential for waste valorization and contribution to circular economy. In this study, bimetallic nanoparticles were produced using extracts derived from and waste, focusing on their green synthesis and antimicrobial activity against Gram-negative bacteria, specifically several strains of . The canes and post-extraction waste from were processed using an ethanol extraction method.

Antibiofilm activity of silver nanoparticles biosynthesized using viticultural waste.

Green methods have become vital for sustainable development of the scientific and commercial sphere; however, they can bring new challenges, including the need for detailed characterization and elucidation of efficacy of their products. In this study, green method of silver nanoparticles (AgNPs) production was employed using an extract from grapevine canes. The aim of the study was to contribute to the knowledge about biosynthesized AgNPs by focusing on elucidation of their antifungal efficiency based on their size and/or hypothesized synergy with bioactive substances from Vitis vinifera cane extract.

Silver Nanoparticle Production Mediated by Cane Extract: Characterization and Antibacterial Activity Evaluation.

The ever-growing range of possible applications of nanoparticles requires their mass production. However, there are problems resulting from the prevalent methods of nanoparticle production; physico-chemical routes of nanoparticle synthesis are not very environmentally friendly nor cost-effective. Due to this, the scientific community started exploring new methods of nanoparticle assembly with the aid of biological agents.

Antimicrobial properties and applications of metal nanoparticles biosynthesized by green methods.

There is a growing interest in the potential and application of metal nanoparticles across many fields. A vast array of techniques for metal nanoparticle synthesis has been discovered; however, sustainability, cost-effectiveness, and environmental concerns favor the green biological approach, using various plant and microbial sources. This review describes the diversity in green methods for nanoparticle biosynthesis, antimicrobial properties of metal nanoparticles and their potential applications.

Resveratrol, pterostilbene, and baicalein: plant-derived anti-biofilm agents.

Microbial adhesion to surfaces and the subsequent biofilm formation may result in contamination in food industry and in healthcare-associated infections and may significantly affect postoperative care. Some plants produce substances with antioxidant and antimicrobial properties that are able to inhibit the growth of food-borne pathogens. The aim of our study was to evaluate antimicrobial and anti-biofilm effect of baicalein, resveratrol, and pterostilbene on Candida albicans, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Escherichia coli.

Enhancing the lipid productivity of yeasts with trace concentrations of iron nanoparticles.

Oxidative stress induced by zero-valent iron nanoparticles (nZVIs) was used to improve lipid accumulation in various oleaginous and non-oleginous yeasts-Candida sp., Kluyveromyces polysporus, Rhodotorula glutinis, Saccharomyces cerevisiae, Torulospora delbrueckii, Trichosporon cutaneum, and Yarrowia lipolytica. The highest lipid yields occurred at 9-13 mg/L nZVIs.

Mitigation of Fe(0) nanoparticles toxicity to Trichosporon cutaneum by humic substances.

Zero-valent iron nanoparticles (nZVI) are a relatively new option for the treatment of contaminated soil and groundwater. However, because of their apparent toxicity, nZVI in high concentrations are known to interfere with many autochthonous microorganisms and, thus, impact their participation in the remediation process. The effect of two commercially available nZVI products, Nanofer 25 (non-stabilized) and Nanofer 25S (stabilized), was examined.

Evaluation of baicalein, chitosan and usnic acid effect on Candida parapsilosis and Candida krusei biofilm using a Cellavista device.

Biofilms are often the cause of chronic human infections and contaminate industrial or medical equipment. The traditional approach has been to use increasing concentrations of antibiotics, but microorganisms rapidly develop multiresistance to them. Therefore, we investigated the use of natural substances as an alternative solution.

Multicomponent biosurfactants--A "Green Toolbox" extension.

The unflagging interest in the surfactants of biological origin, representing ecological alternatives to their synthetic counterparts, has enhanced R&D effort both to produce their new types and to resolve the bottlenecks of their commercialization. In this context, the rhamnolipids, offering a relatively large scale of potential applications, variety of congeners, low toxicity as well as stability towards the extremes of environment, logically attract attention. In this connection, the current state of knowledge concerning these compound exploitation, biosynthesis control and non-genetic factors affecting both production yield and final rhamnolipid product is surveyed.

Structural and physiochemical characterization of rhamnolipids produced by Acinetobacter calcoaceticus, Enterobacter asburiae and Pseudomonas aeruginosa in single strain and mixed cultures.

Rhamnolipids are naturally occurring biosurfactants with a wide range of potential commercial applications. As naturally derived products they present an ecological alternative to synthetic surfactants. The majority of described rhamnolipid productions are single strain Pseudomonas spp.

Pseudomonas biofilms: possibilities of their control.

Genus Pseudomonas includes a large number of species that can be encountered in biotechnological processes as well as in the role of serious human or plant pathogens. Pseudomonads easily form biofilms on various types of surfaces. The biofilm phenotype is characterized by an increased resistance to environmental influences including resistance to antibiotics and other disinfectants, causing a number of problems in health care, food industry, and other areas.

Identification of regioisomers and enantiomers of triacylglycerols in different yeasts using reversed- and chiral-phase LC-MS.

LC with atmospheric pressure chemical ionization (ACPI) MS with RP and chiral phase was used for separation of triacylglycerols (TAGs) from yeasts of the genera Candida, Kluyveromyces, Rhodotorula, Saccharomyces, Torulospora, Trichosporon, and Yarrowia. Chiral LC-APCI-MS is based on using two columns in series packed with a 3,5-dimethylphenyl carbamate modified β-cyclodextrin chiral phase. All regioisomers and enantiomers of TAGs containing one to five double bonds were separated.

Biosynthesis and metabolic pathways of pivalic acid.

Occurrence, biosynthesis, and biodegradation of pivalic acid and other compounds, having a quaternary carbon atom by different bacteria, are described. We have summarized the relevant data that have so far been published, presenting them in a graphical form, i.e.

Effect of surfactants on the biofilm of Rhodococcus erythropolis, a potent degrader of aromatic pollutants.

Bioremediation processes based on biofilms are usually very effective. The presence of (bio)surfactants in such processes can increase bioavailability of hydrophobic pollutants in aqueous phase. However, surfactants can affect the biofilm as well as individual microbial cells in different ways.

The genus Dracunculus--a source of triacylglycerols containing odd-numbered ω-phenyl fatty acids.

Reversed phase liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (RP-HPLC/MS-APCI) was used to identify and quantify triacylglycerols (TAGs) having odd-numbered ω-phenylalkanoic acids from seeds of the flower plant Dracunculus vulgaris, and TAGs from the bacterium Rhodococcus erythropolis prepared by precursor directed biosynthesis from phenylalanine and having the corresponding even-numbered ω-phenylalkanoic acids. Model compounds, which are not commercially available, were prepared by organic synthesis and this allowed us to extend the number of identified natural TAGs to nearly 140 molecular species. Both synthetic and natural compounds containing ω-phenylalkanoic acids were found to have antioxidant and free radical scavenging properties.

RP-HPLC/MS-APCI analysis of branched chain TAG prepared by precursor-directed biosynthesis with Rhodococcus erythropolis.

Reversed phase liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (RP-HPLC/MS-APCI) was used to analyze both synthetic triacylglycerols (TAG) having 1-3 branched fatty acids (FA) in the molecule, and natural TAG prepared by precursor directed biosynthesis from valine, leucine and isoleucine and the corresponding branched short-chain acids in cultivations of Rhodococcus erythropolis. The technique made it possible to identify and quantify TAG differing in a single branched-chain FA. Altogether 11 TAG were synthesized, out of which 8 were synthesized stereospecifically.

Mild hydrolysis of nitriles by Fusarium solani strain O1.

High levels of an aromatic nitrilase (about 37 microkat/L culture) were induced in Fusarium solani O1 after transfer of the mycelium from a rich medium into a medium with 20 mmol/L picolinonitrile. The mycelium was entrapped in lense-shaped particles consisting of a polyvinyl alcohol/polyethylene glycol copolymer (LentiKats). The cell-free extract was immobilized by hydrophobic binding onto a Butyl Sepharose column.

The influence of heavy metals on the production of extracellular polymer substances in the processes of heavy metal ions elimination.

Wastewaters from a chemical industry polluted by heavy metal ions represent a hazard for all living organisms. It can mean danger for ecosystems and human health. New methods are sought alternative to traditional chemical and physical processes.

Colonization of surfaces by phenolic compounds utilizing microorganisms.

The aim of the present study is to determine optimal adhesive interaction of phenolic compounds utilizing Candida maltosa and Rhodococcus erythropolis when adhering to kaolin, silicone, synthetic foil (Steriking R40) and fluorinated silicones, comparing cell and support surface hydrophobicity. In parallel, the interfering effect of detergents was investigated. Data obtained show that the less hydrophobic supports display high initial cell adhesion when contacted with the cell type with a lower surface hydrophobicity (yeast cell) but most stable yeast biofilms are those formed on highly hydrophobic fluorinated silicones.

The enhancement of reproduction and biodegradation activity of eukaryiotic cells by humic acids.

Fourteen samples of humic acids (HA) were screened for ability to influence reproduction and biodegradation activity of eukaryotic cells in the presence of chosen toxic pollutants. Microorganisms Candida maltosa and Rhodotorula mucilaginosa (soil isolates) were used for all tests. It was observed during our experiments that some samples of humic acids served as a protection against the high concentration of toxic pollutants (phenol, naphtalene etc).

Comparison of yeast (Candida maltosa) and bacterial (Rhodococcus erythropolis) phenol hydroxylase activity and its properties in the phenolic compounds biodegradation.

Aromatic contaminants of the environment, to which belongs phenol and its derivatives, are toxic and in most of the cases hard to degrade. Removal of these pollutants by biological, gentle and effective way, depends on specific environmental conditions in the locality and on the biodegradation potential of the used microbial population. Closer characterization of the biodegradation and enzyme mechanisms is therefore an essential assumption of the successful implementation of microbes.

Capacity of the bioremediation technology for clean-up of soil and groundwater contaminated with petroleum hydrocarbons.

A column reactor was designed and used to simulate conditions affecting the bioremediations of petroleum hydrocarbons. The work illustratively describes the aerobic (model) clean-up of soil samples enabling to predict the efficiency of a technology installed in parallel on contaminated former airport. The data showing the performance of thus precharacterized technology are presented.

Host-vector system for phenol-degrading Rhodococcus erythropolis based on Corynebacterium plasmids.

The strain Rhodococcus erythropolis CCM2595, which was shown to degrade phenol, was chosen for genetic studies. To facilitate strain improvement using the methods of gene manipulation, the technique of genetic transfer was introduced and cloning vectors were constructed. Using the plasmid pFAJ2574, an electrotransformation procedure yielding up to 7x10(4) transformants/microg DNA was optimized.