Fabrication of wound dressings: Herbal extract-loaded nanoliposomes embedded in fungal chitosan/polycaprolactone electrospun nanofibers for tissue regeneration.

Wound healing is a complex process and one of the major therapeutic and economic subjects in the pharmaceutical area. In recent years, the fabrication of nano-sized wound dressing models has attracted great attention for tissue regeneration. Plant extracts loaded nanoparticles are environmentally friendly and non-toxic and the release of the bioactive substance will be controlled to the wound area. This study aims to fabricate wound dressing models that contain bioactive components for tissue regeneration. Fungal chitosan/polycaprolactone nanofiber was fabricated by electrospinning and it has been characterized. Plant extracts loaded nanoliposomes were prepared, characterized, and embedded in nanofiber structures. The effectiveness of wound dressing models for tissue regeneration was evaluated by in vitro and in vivo studies. It was observed that all wound dressing models positively affect the cell viability of human dermal fibroblast cells. It was determined that plant extracts loaded nanoparticles embedded in nanofibers increased in cell viability than nanoparticles that were non-embedded in nanofiber structures. Histological analysis showed that plant extract-loaded nanoliposomes embedded in chitosan/PCL nanofibers were used for tissue regeneration. The most effective nanofibers were determined as Wd-ClNL nanofibers. RESEARCH HIGHLIGHTS: Hypericum perforatum L. and Cistus laurifolius L. were prepared by modified ultrasonic extraction method. Fungal chitosan/polycaprolactone nanofiber was fabricated by electrospinning and it has been characterized. Plant extract-loaded nanoliposomes were prepared, and characterized. They were embedded in chitosan/polycaprolactone nanofiber. Effects of the wound dressing model were analyzed by in vitro and in vivo assays for tissue regeneration.

Production of fungal chitosan and fabrication of fungal chitosan/polycaprolactone electrospun nanofibers for tissue engineering.

The present study investigated that chitosan production of Rhizopus oryzae NRRL 1526 and Aspergillus niger ATCC 16404. Fungal chitosans were characterized by scanning electron microscopy (SEM)-energy dispersive X-ray analysis, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter and deacetylation degrees of fungal chitosans were determined. The percentage yield of Ro-chitosan and An-chitosan were determined as 18.6% and 12.5%, respectively. According to percentage of chitosan yield and the results of the characterization studies, chitosan that obtained from Rhizopus oryzae NRRL 1526 was selected for subsequent studies. Cytotoxicity of chitosan obtained from Rhizopus oryzae NRRL 1526 was determined by MTT assay on human dermal fibroblast cell line. Acording to results of the cytotoxicity test fungal chitosan was nontoxic on cells. The high cell viability was observed 375 µg/mL concentration at 24th, 48th h periods and at the 187.5 µg/ml 72nd h periods on cells. The fungal chitosan obtained from Rhizopus oryzae NRRL 1526 was used to fabrication of electrospun nanofibers. Fungal chitosan based polymer solutions were prepared by adding different substances and different electrostatic spinning parameters were used to obtain most suitable nanofiber structure. Characterization studies of nanofibers were carried out by SEM, FTIR and X-ray diffraction. The most suitable nanofiber structure was determined as F4 formula. The nanofiber structure was evaluated to be thin, bead-free, uniform, flexible and easily remove from surface and taking the shape of the area. After the characterization analysis of fungal chitosan it was determined that the chitosan, which obtained from Rhizopus oryzae NRRL 1526 is actually chitosan polymer and this polymer is usable for pharmaceutical areas and biotechnological applications. The electrospun nanofiber that blends fungal chitosan and PCL polymers were fabricated successfully and that it can be used as fabrication wound dressing models. RESEARCH HIGHLIGHTS: Extraction of chitosan from Rhizopus oryzae NRRL 1526 and Aspergillus niger ATCC 16404 and characterization scanning electron microscopy-energy dispersive X-ray analysis, Fourier transform infrared spectroscopy, differential scanning calorimeter. Fabrication and characterization of the fungal chitosan/PCL electrospun nanofibers.

Fatty acid methyl ester analysis of Aspergillus fumigatus isolated from fruit pulps for biodiesel production using GC-MS spectrometry.

In this study, a total of six fungal samples were isolated from apple, strawberry and orange pulp. DNA sequence analysis was used as molecular identification method. ITS region was aligned in DNA sequence analysis, and an algorithm sequence similarity was done using BLAST (Basic Local Alignment Search Tool) program to identify these isolates. All the six isolates were identified as Aspergillus fumigates. The total lipid content was varied in the isolates which were ranged from 29.4 to 21.0 mg/100 ml. Moreover, the obtained lipid form mycelium biomass of the isolates was transesterified by a base catalyst. The methyl esters were analyzed by using GC-MS. GC-MS Spectrometry revealed the presence of different fatty acids with long chain (C11:0, C15:0, C17:1, C18:2, C16:1). High efficiency biodiesel can be obtained using long-chain fatty acids. Fatty acid profiles of A. fumigatus isolated from different fruit pulps have confirmed its potentiality as well as showed the beneficial utilization of these fatty acids for biodiesel production.

Mutagenic and cytotoxic activities of benfuracarb insecticide.

Benfuracarb is a carbamate insecticide used to control insect pests in vegetables and it has anti-acetylcholinesterase activity lower than other carbamates. Cytotoxic effects of benfuracarb were evaluated by using root growth inhibition (EC50), mitotic index (MI), and mitotic phase determinations on the root meristem cells of Allium cepa and mutagenic effects were determined in Salmonella typhymurium Ames test by TA98 and TA100 strains with and without metabolic activation. In Allium test, 1 % DMSO was used as negative control group and 10 ppm MMS was used as positive control group. 75 ppm concentration of benfuracarb was found as EC50. In MI and mitotic phases determination study, 37.5, 75 and 150 ppm doses of benfuracarb were used. Dose-dependent cytotoxic activity was found by root growth inhibition and MI studies. It was identified that mitotic inhibition activity of benfuracarb was higher than 10 ppm MMS. In Ames test, mutagenic activity was not observed and over 200 µg/plate of benfuracarb was determined as cytotoxic to S. typhymurium strains. Benfuracarb can be called as "mitotic inhibitor" but not called as mutagen.

Cytotoxic and genotoxic effects of dioxacarb by human peripheral blood lymphocytes CAs and Allium test.

Dioxacarb (Elecron, Famid) is a phenyl methylcarbamate insecticide and in vitro cytotoxic and genotoxic effects of this pesticide on human peripheral blood lymphocytes and Allium root meristematic cells were investigated by chromosomal aberrations (CAs) and Allium test. Human lymphocytes were treated with 62.5, 125, 250 and 500 ppm doses of dioxacarb for CAs. CA/cell, abnormal cell % and mitotic index % (MI %) data were obtained from these concentrations in 24 and 48 h treatment periods. Dioxacarb did not increase the CA/cell frequency significantly, so this insecticide was not identified as genotoxic. But it was found cytotoxic especially at 250 and 500 ppm concentrations because of the reduced the MI % and increased the abnormal cell %. In Allium test, 25 ppm (EC50/2), 50 ppm (EC50) and 100 ppm (EC50 × 2) concentrations were used for root growth inhibition (EC50 determination) and Allium mitotic index (MI) determination tests. The used concentrations of dioxacarb induced dose-dependent inhibition of MI and root growth on root meristems. Mitotic inhibition of dioxacarb was found significantly higher than for the positive control. These Allium results indicated the high cytotoxicity of dioxacarb. The present study is the first research on cytotoxicity and genotoxicity of dioxacarb by human lymphocyte CAs and Allium test.

Evaluation of germination, root growth and cytological effects of wastewater of sugar factory (Afyonkarahisar) using Hordeum vulgare bioassays.

In this study, the effect of Afyonkarahisar Sugar Factory's discharge water on germination percentage, root growth and mitotic divisions of the root tip cells of Hordeum vulgare L. were investigated. Six concentrations of wastewater and ranging from 10(0), 10( -1), 10( -2), 10( -3), 10( -4), 10( -5), were applied for 6, 12, 18 and 24 h, respectively. It was observed that the treatments reduced the germination percentages of H. vulgare grains and inhibited the root growth as well as reduced mitotic index compared to the control group at all concentrations. It was also observed that the increase of the concentrations of wastewater decreased the cell division, and several mitotic anomalies such as c-mitosis, lagging chromosomes, multipolar anaphases and chromosome bridges increased.