Publications by authors named "Ivan Atanassov"

ssp. essential oil (OEO) is a natural oil with high therapeutic potential. For some applications, however, the development of novel formulations is still needed to improve the bioavailability and stability of OEO.

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This study attempts to provide a deeper insight into the current genetic status of 12 Bulgarian autochthonous sheep breeds using microsatellite (SSR) markers. A total of 600 individuals from 50 flocks were analyzed using a panel of 13 SSR markers. In total, 228 alleles were found in the studied microsatellite loci.

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This study reports the development of a set of 20 highly polymorphic genomic SSR markers which can be used for both cultivar identification and genetic diversity studies in several species, including some of the most popular ones like Greek oregano ( L. ssp. ), common oregano ( L.

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The indigenous yeasts associated with the spontaneous fermentation of phenolic-rich rose oil distillation wastewater (RODW) generated after the industrial distillation of rose oil were studied. The ITS-rDNA sequence analysis of the samples collected from RODW fermented at semi-sterile conditions, a waste deposition lagoon and endophytic yeasts isolated from industrially cultivated suggests that the spontaneous RODW fermentation is caused by yeasts from the genus found also as endophytes in the rose flowers. Phylogenetic analysis based on the nucleotide sequences of the translation elongation factor (TEF1α) and 18S- and 26S- rRNA genes further confirmed the taxonomic affiliation of the RODW yeast isolates with the genus .

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We studied the genetic and flower volatile diversity in natural populations of subsp. (Link) Ietsw. in Bulgaria using simple sequence repeat (SSR) and sequence-related amplified polymorphism (SRAP) markers and gas chromatography/mass spectrometry (GC/MS) analysis of flower volatiles from individual plants.

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The cellulose synthase complex (CSC) exhibits a 6-fold symmetry and is known as a "rosette." Each CSC is believed to contain between 18 and 24 CESA proteins that each synthesize an individual glucan chain. These chains form the microfibrils that confer the remarkable structural properties of cellulose.

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Archaeal and bacterial diversity in two Bulgarian hot springs, geographically separated with different tectonic origin and different temperature of water was investigated exploring two genes, 16S rRNA and GH-57. Archaeal diversity was significantly higher in the hotter spring Levunovo (LV) (82°C); on the contrary, bacterial diversity was higher in the spring Vetren Dol (VD) (68°C). The analyzed clones from LV library were referred to twenty eight different sequence types belonging to five archaeal groups from Crenarchaeota and Euryarchaeota.

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Plant cellulose microfibrils are synthesized by a process that propels the cellulose synthase complex (CSC) through the plane of the plasma membrane. How interactions between membranes and the CSC are regulated is currently unknown. Here, we demonstrate that all catalytic subunits of the CSC, known as cellulose synthase A (CESA) proteins, are S-acylated.

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Water steam distillation of rose flowers separates the essential oil from the polyphenol-containing rose oil distillation wastewater. Recently, a strategy was developed to separate rose oil distillation wastewater into a polyphenol depleted water fraction and a polyphenol-enriched fraction [RF20-(SP-207)]. The objective of the present study was to investigate RF20-(SP-207) and fraction F(IV), augmented in quercetin and ellagic acid, for possible antiproliferative effects in immortalized human keratinocytes (HaCaT) since rose petals are known to contain compounds with potential antiproliferative activity.

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During the water steam distillation process of rose flowers, the non-volatile phenolic compounds remain in the waste. We recently developed a strategy to separate rose oil distillation water (RODW) into a polyphenol depleted water fraction and a polyphenol enriched fraction (RF20-SP207). Bioassay-guided investigation of RF20-SP207 led to the isolation of quercetin, kaempferol and ellagic acid.

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The production of rose oil from rose flowers by water steam distillation leaves a water fraction of the distillate as main part of the waste. Therefore, the rose oil distillation wastewater represents a serious environmental problem due to the high content of polyphenols which are difficult to decompose and have to be considered as biopollutants when discarded into the drainage system and rivers. On the other hand, natural polyphenols are valuable compounds with useful properties as bioactive substances.

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There are 10 genes in the Arabidopsis genome that contain a domain described in the Pfam database as domain of unknown function 579 (DUF579). Although DUF579 is widely distributed in eukaryotic species, there is no direct experimental evidence to assign a function to it. Five of the 10 Arabidopsis DUF579 family members are co-expressed with marker genes for secondary cell wall formation.

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Article Synopsis
  • The study explores the diversity of Archaea in a hot spring in Varvara, Bulgaria, using a culture-independent molecular phylogenetic analysis.
  • A total of 35 archaeal operational taxonomic units (OTUs) were identified, primarily associated with the phylum Crenarchaeota, which had the most representatives.
  • The findings highlight a significant number of uncultivated and novel archaeal groups, including new OTUs that don’t closely relate to known sequences, indicating a wider range of archaeal diversity than previously understood.
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Background: The progress and completion of various plant genome sequencing projects has paved the way for diverse functional genomic studies that involve cloning, modification and subsequent expression of target genes. This requires flexible and efficient procedures for generating binary vectors containing: gene fusions, variants from site-directed mutagenesis, addition of protein tags together with domain swaps and deletions. Furthermore, efficient cloning procedures, ideally high throughput, are essential for pyramiding of multiple gene constructs.

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Cellulose is the most abundant biopolymer in nature; however, questions relating to the biochemistry of its synthesis including the structure of the cellulose synthase complex (CSC) can only be answered by the purification of a fully functional complex. Despite its importance, this goal remains elusive. The work described here utilizes epitope tagging of cellulose synthase A (CESA) proteins that are known components of the CSC.

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