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Celem pracy była analiza danych literaturowych z zakresu rozwiązań konstrukcyjnych biosensorów wykorzystywanych w detekcji fitopatogenów. Omówiono ogólne zasady działania biosensorów i mechanizmy generowania sygnału analitycznego. Szczególną uwagę zwrócono na biosensory zawierające w swojej budowie nanomateriały, zw. nanobiosensorami. Nanomateriały mogą wchodzić w skład warstwy receptorowej biosensora, przetwornika oraz obu tych elementów. Stabilizują one i przytwierdzają do powierzchni przetwornika cząsteczki receptorów biologicznych lub pełnią rolę znaczników wzmacniających sygnał analityczny. Dzięki temu w porównaniu do biosensorów bazujących na standardowych rozwiązaniach charakteryzują się lepszymi parametrami pracy. Nanobiosensory wykorzystywane w fitopatologii to przeważnie genosensory (zawierające w warstwie receptorowej aptamery, czyli jednoniciowe oligonukleotydy DNA, ssDNA) lub immunosensory (zawierające przeciwciała zdolne do rozpoznawania specyficznych struktur bakterii fitopatogennych lub białek płaszcza wirusów roślinnych). W obu typach urządzeń stosuje się zwykle elektrochemiczną lub optyczną transdukcję sygnału biologicznego. Zacznie rzadziej są spotykane genosensory z transdukcją mikrograwimetryczną, opierającą się na technice mikrowagi kwarcowej. Zaprezentowane biosensory i nanobiosensory charakteryzowały się w warunkach laboratoryjnych dobrymi parametrami analitycznymi, co wskazuje na ich duży potencjał aplikacyjny.

Biotechnological methods can be used in dairy cow reproduction to increase reproductive potential and improve economic outcomes of milk production. Biotechnological methods widely used in reproduction include artificial insemination and embryo transfer, and more recently insemination with sexed semen, which makes it possible to control the sex of the offspring. This study presents an analysis of the effectiveness of the use of sexed semen in a selected herd of dairy cows. The results confirmed the effectiveness of sexed semen at increasing births of female calves. Sexed semen was most effective among heifers. In that group the fewest insemination doses were required for conception (1.54), and pregnancy after the first insemination procedure was noted in 52.2% of cases. The values of selected fertility parameters (calving-to-first-service interval, service period, services per conception, and rate of conception after first service) did not deviate significantly from recommended values in cows inseminated with sexed and unsexed semen. Among the group of cows inseminated with sexed semen, fertility parameters were significantly more favourable than in the group inseminated with conventional semen.

Background: In addition to nutrients, plant raw materials for food production should also contain substances with beneficial biological properties, which unquestionably include antioxidant compounds. Among the numerous methods of determining the antioxidant properties of samples of plant material, biological methods that provide information about not only the in vivo antioxidant potential of samples but also their metabolism and bioavailability are increasingly valued. Objective: The aim of the study was to assess the antioxidant properties of extracts from large cranberry (Vaccinium macrocarpon) obtained from different producers. Methods: Biologically active compounds were extracted from cranberry fruits using water alone and ethyl alcohol–water in proportions of 1+1 and 4+1 (v/v) as solvents. The following were determined in the extracts: content of phenolic compounds and anthocyanins, total antioxidant capacity based on reduction of the ABTS+• [2,20-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid)] radical cation, and antioxidant properties as reflected by the growth of a Saccharomyces cerevisiae Δsod1 mutant in a liquid hypertonic environment. The growth parameters of this Δsod1 mutant, monitored by a method exploiting a color reaction with resazurin, reflected the antioxidant properties of the extracts. Results: The ethanol–water cranberry extracts showed higher content of polyphenols, anthocyanins, and total antioxidants expressed as Trolox equivalent, determined on the basis of ABTS+• reduction. Conclusions: The antioxidant properties determined by the bioassay did not respond strongly to the data obtained in the in vitro chemical and biochemical assays, because they were more closely associated with the batch of fruit than with the type of solvent used to extract phytochemicals.

Iodine is an essential trace element for humans, and iodine deficiency is a significant health problem. In this study, an improved method for iodine biofortification based on seed germination was established. Solutions of KI (0.15, 0.30, 0.75 and 1.5 mg∙g−1 of seeds) were applied to germinating radish seeds of two cultivars Raphanus sativus L. var. sativus: Warta and Zlata. Compared with the control (seeds treated with water) the iodine content (in the radish sprouts produced by germinating seeds treated with KI were approximately 112.9–2730 times higher. The application KI rates did not adversely affect the biological quality of the radish sprouts. Regarding the biological quality of the iodine-enriched seedlings, we determined their length, dry mater, protein, soluble sugars, chlorophylls, total phenol, ascorbic acid, thiol group content and total antioxidant capacity. The effect of potassium iodide on the selected parameters of their biological quality varied depending on the KI doses and radish cultivars. The results showed that the most appropriate biofortification application rates were 0.15 and 0.30 mg KI per g seeds, because the enriched seedlings had excellent biological quality parameters.

In our investigation, the chemical composition and bioactive potential of leaf buds of raspberry, blackberry, and a raspberry-blackberry hybrid were determined. Antioxidant and antimicrobial properties were tested in water (W), ethanol-water (EW), and glycerol-water (GW) extracts from the buds. These plant organs contain relatively large amounts of minerals, especially Fe. The total antioxidant capacity (TAC) measured by the ABTS and DPPH methods ranged from 2.86 to 12.19 and 6.75 to 24.26 mmol per 100 g fresh weight (FW) of buds, respectively. TAC values were generally higher in the raspberry than in the case of blackberry and raspberry-blackberry hybrid extracts. The antioxidant properties of the extracts were strongly positively correlated with their content of total phenolic (TP). No such relationship was noted for ascorbic acid (AA), whose concentration in all extracts was at a similarly low level. Antioxidant properties determined in vitro were confirmed for the GW extract from raspberry leaf buds in biological test based on the growth parameters of &Delta, sod1Saccharomyces cerevisiae mutant cells in hypertonic medium. The extracts also exhibited strong antibacterial properties against Staphylococcus aureus and Enterococcus faecalis and weaker against Enterobacter aerogenes. The studied leaf buds could be therefore an unconventional source of minerals, natural antioxidants and antibacterial compounds with potential applications in the food, pharmaceutical, and cosmetics industries.

The aim of the study was to evaluate the content of major bioactive compounds (BACs) and the antioxidant properties of aqueous berry extracts using ABTS•+ and DPPH• biochemical assays and a novel bioassay based on the growth of a Δsod1 mutant of Saccharomyces cerevisiae on osmotic shock plates (OSPs). The extracts were prepared from raspberry (‘Cascada Delight’, ‘Glen Fyne’ and ‘Octavia’) cultivars, blackberry (‘Navaho’) cultivar, and wild blackberry, as well as a raspberry-blackberry hybrid. Concentrations of phenolic compounds, anthocyanins and ascorbic acid differed significantly in the fruit extracts, but were highest in the raspberry-blackberry hybrid. The antioxidant activity against DPPH• and ABTS•+ among the berry cultivars and hybrid was highly dependent on the anthocyanin content. The Δsod1 yeast mutant growth test confirmed the antioxidant properties of all the extracts, with the variant based on counting of single colonies proving more sensitive than the spot test.

The aim of this study was to select optimal conditions (C and N sources, initial pH and temperature) for biodecolorization of 0.03% anthraquinone dye Alizarin Blue Black B (ABBB) by microscopic fungi: Haematonectria haematococca BwIII43, K37 and Trichoderma harzianum BsIII33. The phenolic compounds, phytotoxicity (Lepidium sativum L.), biotoxicity (Microtox), cytotoxicity and yeast viability assay were performed to determine the extent of ABBB detoxification. Biodecolorization and detoxification of 0.03% ABBB in H. haematococca BwIII43 and T. harzianum BsIII33 cultures was correlated with extracellular oxidoreductases activity. In turn, secondary products, toxic to human fibroblasts and respiring sod1 Saccharomyces cerevisiae cells, were formed in H. haematococca K37 strain cultures, despite efficient decolorization.

Effects of the absence of Cu,Zn-superoxide dismutase (CuZnSOD) on the replicative life span of the yeast Saccharomyces cerevisiae were studied under different oxygen conditions. In both strains, replicative life span and the rate of cell divisions were found to be similar under the atmosphere of air and under hypoxic (3% oxygen) and anoxic conditions. These results indicate that deleterious consequences of the lack of CuZnSOD are not limited to elevation of superoxide concentration and involve function(s) other than superoxide scavenging.

Yeast (Saccharomyces cerevisiae) mutants lacking CuZn-superoxide dismutase (CuZnSOD) are hypersensitive to oxygen and have significantly decreased replicative life span. Both these defects can be ameliorated by exogenous ascorbate. The effect of ascorbate on life span is complicated by auto-oxidation of its compound in the medium. If negative effects of auto-oxidation are prevented by exchange of the medium, ascorbate prolongs not only mean but also maximal replicative life span of the yeast in the atmosphere of air and of pure oxygen. These results demonstrate that life span shortening due to the lack of a vital antioxidant enzyme can be ameliorated by a low-molecular weight antioxidant.