RESUMEN
The present study is the first to report Xylaria karsticola isolated from the basidiocarp of Macrolepiota procera (Basidiomycota), from Stara Planina Mountain, Bulgaria and second report for such species found in Europe. The fungal isolate was in vitro cultivated and the morphology was observed. It was primarily determined as a xylariaceous morphotype at the intragenus level, based on the evaluation of colony growth rate, color, and stromatic structure formation and was confirmed by unique conidiophores and conidia. The molecular identification of the isolate was performed by amplification of ITS1-5.8S-ITS2 region and the strain was identified as Xylaria karsticola with 97.57% of confidence. The obtained sequence was deposited in the GenBank database under the accession number MW996752 and in the National Bank of Industrial Microorganisms and Cell Cultures of Bulgaria under accession number NBIMCC 9097. The phylogenetic analysis of the isolate was also conducted by including 26 sequences obtained from different Xylaria isolates. Considering the phylogenetic data, X. karsticola NBIMCC 9097 was grouped along with other X. karsticola isolates, although the DNA sequence of the novel X. karsticola was rather distantly related to the other X. karsticola sequence data. The results were supported by the bootstrap analysis (100%) and indicated the different origin of the examined X. karsticola NBIMCC 9097.
Asunto(s)
Ascomicetos , Basidiomycota , Bulgaria , Filogenia , Basidiomycota/genética , Bases de Datos de Ácidos NucleicosRESUMEN
Higher basidiomycetes are recognized as functional foods due to their bioactive compound content, which exerts various beneficial effects on human health, and which have been used as sources for the development of natural medicines and nutraceuticals for centuries. The aim of this study was to evaluate and compare the biological potential of basidiocarp and mycelial biomass produced by submerged cultivation of a new regionally isolated oyster mushroom. The strain was identified with a high percentage of confidence (99.30%) as Pleurotus ostreatus and was deposited in the GenBank under accession number MW 996755. The ß-glucan content in the basidiocarp and the obtained mycelial biomass was 31.66% and 12.04%, respectively. Three mycelial biomass and basidiocarp extracts were prepared, and the highest total polyphenol content (5.68 ± 0.15 mg GAE/g DW and 3.20 ± 0.04 mg GAE/g DW) was found in the water extract for both the fruiting body and the mycelium biomass. The in vitro antioxidant activity of the extracts was investigated, and it was determined that the water extracts exhibited the most potent radical scavenging activity. The potential ability of this new fungal isolate to affect the contractile activity (CA) of dissected smooth muscle preparations (SMP) was examined for the first time. It was found that oyster mushrooms likely exhibit indirect contractile effects on the gastric smooth muscle (SM) cells.
RESUMEN
In this study, for the first time, the potential of rose flowers and lavender straw waste biomass was studied as feeding lignocellulose substrates for the cultivation of newly isolated in Bulgaria Ganoderma resinaceum GA1M with the objective of obtaining mycelium-based bio-composites. The chemical characterization and Fourier Transform Infrared (FTIR) spectroscopy established that the proximate composition of steam distilled lavender straw (SDLS) and hexane extracted rose flowers (HERF) was a serious prerequisite supporting the self-growth of mycelium bio-materials with improved antibacterial and aromatic properties. The basic physico-mechanical properties of the developed bio-composites were determined. The apparent density of the mycelium HERF-based bio-composites (462 kg/m3) was higher than that of the SDLS-based bio-composite (347 kg/m3) and both were much denser than expanded polystyren (EPS), lighter than medium-density fiber board (MDF) and oriented strand board (OSB) and similar to hempcrete. The preliminary testing of their compressive behavior revealed that the compressive resistance of SDLS-based bio-composite was 718 kPa, while for HERF-based bio-composite it was 1029 kPa and both values are similar to the compressive strength of hempcrete with similar apparent density. Water absorbance analysis showed, that both mycelium HERF- and SDLS-based bio-composites were hydrophilic and further investigations are needed to limit the hydrophilicity of the lignocellulose fibers, to tune the density and to improve compressive resistance.
RESUMEN
Traditional sourdoughs in Bulgaria were almost extinct during the centralized food production system. However, a rapidly developing trend of sourdough revival in the country is setting the demand for increased production and use of commercial starter cultures. The selection of strains for such cultures is based on geographical specificity and beneficial technological properties. In this connection, the aim of this study was to isolate, identify and characterize lactic acid bacteria (LAB) and yeasts from typical Bulgarian sourdoughs for the selection of strains for commercial sourdough starter cultures. Twelve samples of typical Bulgarian sourdoughs were collected from different geographical locations. All samples were analyzed for pH, total titratable acidity and dry matter content. Enumeration of LAB and yeast was also carried out. Molecular identification by 16S rDNA sequence analysis was performed for 167 LAB isolates, and 106 yeast strains were identified by ITS1-5.8S-ITS2 rRNA gene partial sequence analysis. The LAB strains were characterized according to their amylolytic and proteolytic activity and acidification capacity, and 11 strains were selected for further testing of their antimicrobial properties. The strains with the most pronounced antibacterial and antifungal activity are listed as recommended candidates for the development of starter cultures for sourdoughs or other food products.
