The aim of our study is to determine microbial contamination, antibacterial and antioxidant activities of 14 pollen samples of Corylus avellana collected from different locations in Slovakia. Microbiological analysis was carried out in two steps: microbiological assays and studies of antibacterial activity of pollen extracts. The antimicrobial properties of pollen extracts were carried out with the disc-diffusion method. Methanol (70%), ethanol (70%) and distilled water were used for pollen extracts. Five strains of bacteria such as gram-negative (Salmonella enterica subsp. enterica CCM 3807, Escherichia coli CCM 2024, and Yersinia enterocolitica CCM 5671) and gram-positive (Staphylococcus aureus CCM 2461 and Bacillus thuringiensis CCM 19T) were tested. Antioxidant activity of pollen extracts was determined by the DPPH method. Bacterial analysis includes the determination of the total bacterial count ranged from 4.08 to 4.61 log CFU g−1, mesophilic aerobic bacteria ranged from 3.40 to 4.89 log CFU g−1, mesophilic anaerobic bacteria ranged from 3.20 to 4.52 log CFU g−1, coliform bacteria ranged from 3.30 to 4.55 log CFU g−1, yeasts and filamentous fungi ranged from 3.00 to 3.56 log CFU g−1. Microscopic filamentous fungi Aspergillus spp., Alternaria spp., Penicillium spp., Cladosporium spp., Rhizopus spp., and Paecylomyces spp. were isolated from hazelnut pollen. Yersinia enterocolitica was the most sensitive strain among ethanolic and methanolic pollen hazelnut extracts. Staphylococcus aureus was the most sensitive strain against aqueous hazelnut pollen extracts. We determined the following sensitivity against ethanol pollen extracts respectively: Yersinia enterocolitica > Salmonella enterica > Staphylococcus aureus > Bacillus thuringiensis > Escherichia coli. Methanol pollen extracts had shown following sensitivity: Yersinia enterocolitica > Salmonella enterica > Escherichia coli > Staphylococcus aureus > Bacillus thuringiensis. Aqueous extracts had shown the following sensitivity: Staphylococcus aureus > Salmonella enterica > Escherichia coli > Bacillus thuringiensis > Yersinia enterocolitica. Hazelnut pollen extracts have over 82% antioxidant capacity in samples from non-urban zones. An elevated level of antioxidant potential in the pollen is determined by its biological properties conditioned by biologically active substances. DPPH method allowed characterizing pollen as a source of antioxidants.
1 December 2021 in Journal of microbiology, biotechnology and food sciences
Plants have metabolites and mechanisms that provide them with the basic building blocks for germination, growth, and reproduction processes, while providing them with protection and increasing their adaptation to environmental stresses. Due to their multifunctional significance, cyanogenic glycosides (CNG) indicate the importance of their role in the plant organism. Their diversity and biochemical origin are worth noting. Paradoxically, several nutritionally important food sources of plant origin are characterized by the presence of cyanogenic glycosides in various tissues. Processing approaches of plant food resources ensure a reduction in the content of these ingredients to an acceptable safe level. Different bacteria-based biotechnological processes are applied to minimize the content of CNG in food products. For the usability and identification of the added value of plant food resources, it is important to know the functions and importance of antinutritional components of metabolism with a consequent impact on nutrition and health. In the review we provided a comprehensive view of the importance and potential of CNG in plants with a focus on food sources, where the model object was presented by linseed.
The aim of our long-term research program is to improve the quality and quantity of amaranth production through mutation breeding using γ-radiation. In this paper, we present the characterization of the new variety ‘Zobor’ of A. hypochondriacus × A. hybridus developed by radiation-induced mutagenesis of hybrid K-433. Multiyear phenotypic characterization of an important yield parameter (1000-seed weight) showed that the studied mutant variety ‘Zobor’ has an advantage in seed weight over the nonirradiated control seeds of K-433 with predictable performance of this yield trait. ‘Zobor’ exhibited changes in seed morphometric parameters, starch particle size, and pasting properties with no change in amylose content and swelling power. Moreover, the seeds of ‘Zobor’ showed the significantly highest folate content among selected amaranth varieties. The mutant variety could, therefore, be interesting for the development of functional foods and as a low-management crop, attractive for cultivation in Europe.
The review summarizes diverse knowledge about the problem ofLinum usitatissimumL. response on photoperiod. Within this species, high genetic variability of the photosensitivity degree and influence of photoperiod on different plants characters were discovered. It was shown that in flax, earliness of flowering in long daylight is not strictly related to the low photosensitivity, and late genotypes with low photosensitivity can be found. In short daylight, various plant characters of different genotypes can be stable or display different reactions: increase or decrease their values. Also, the degree of photosensitivity does not have stable correlations with agronomic characters.
1 December 2015 in Agriculture (pol'nohospodárstvo)
MicroRNAs (miRNAs) are a class of non-coding RNAs about 20-24 nucleotides long. They play an important role in the gene regulation at the post-transcriptional level. They affect the plant genome response to environmental stress. The miRNA-based molecular markers is type of functional markers reported in very few plants. However, the information connected to the evaluation of genotypes by this type of markers within a single species is missing. Considering the stability, polymorphism, functionality and transferability potential of miRNA-based markers, the research was conducted to apply selected types of them (miR156b, miR408a and the combined type of miR156b/miR408a) for the genotyping analysis of eight flax genotypes of different origin together with the morphology analyses. A total of 145 miRNA loci were identified, of which 19 were unique. The highest numbers of miRNA loci (57) and unique fragments (9) as well as the highest percentage of polymorphism and the extent of polymerase chain reaction (PCR) amplification of miRNA fragments have been observed with the combination of miR156b-F and miR408-F markers. By means of the miRNA markers has been recorded the unique profile of the miRNA loci for individual accessions. The morphology study has shown that the genotypes are the same in the expression of selected morphological traits despite the different use and different places of origin. However, we have identified an interface between some of morphological traits and miRNA-based markers for genotyping the genetic resources of flax. By mutually linking these two types of markers, we were able to determine unique genotypes of flax.