Ilona Kerienė

Betula and Pinus pollen, which are dispersed in natural surface waters, release biologically active compounds into the water bodies. This study aims to evaluate variations in the distribution and composition of phenolic compounds in suspended particles in natural water bodies during pollen spreading. Samples taken from water bodies of different trophic levels were analyzed by microscopy, UV/VIS spectroscopy, HPTLC, and HPLC/DAD. The study revealed that the total phenolic content in water-suspended particles varied from 3.0 mg/g to 11.0 mg/g during Betula and Pinus pollen spreading. It was also observed that the surface water of dystrophic natural lakes had a higher content of phenolic compounds than the eutrophic, hypereutrophic, and mesotrophic water bodies. Chlorogenic, trans-ferulic, vanillin, and 3,4-dihydroxybenzoic acids were frequently detected in the surface water samples. Experimental measurements have shown variations in the release of phenolic compounds from Betula pollen into water (p < 0.05). After the exhibition of pollen, the distilled water predominantly contained bioactive chlorogenic acid. Further in situ investigations are necessary to gain a more comprehensive understanding of the function of phenolic compounds in aquatic ecosystems. The exploration of the release of bioactive compounds from pollen could provide valuable insights into the potential nutritional value of pollen as a nutrient source for aquaculture.

In this study, phenolic compounds and their antioxidant activity in the pollen of anemophilous Betula and Pinus were determined. Spectrophotometric, high-performance thin-layer and liquid chromatography methods were applied. Free phenolic compounds (free PC) and phenolic compounds bound to the cell wall (bound PC) were analysed in the pollen extracts. Regardless of the pollen species, their content was 20% higher than that in bound PC extracts. Pinus pollen extracts contained 2.5 times less phenolic compounds compared to Betula. Free PC extraction from the deeper layers of Pinus pollen was minimal; the same content of phenolic compounds was obtained in both types of extracts. The bioactivity of pollen (p < 0.05) is related to the content of phenolic compounds and flavonoids in Betula free PC and in bound PC, and only in free PC extracts of Pinus. Rutin, chlorogenic and trans-ferulic acids were characterised by antioxidant activity. Phenolic acids accounted for 70–94%, while rutin constituted 2–3% of the total amount in the extracts. One of the dominant phenolic acids was trans-ferulic acid in all the Betula and Pinus samples. The specific compounds were vanillic and chlorogenic acids of Betula pollen extracts, while Pinus extracts contained gallic acid. The data obtained for the phenolic profiles and antioxidant activity of Betula and Pinus pollen can be useful for modelling food chains in ecosystems.

Phthalates are plasticisers dangerous to ecosystems and humans.The paper aims to review the exposure of high-concern phthalates resulting from industrial and domestic activities to wastewater and analyse the advanced technologies used in European countries to remove phthalates from wastewater. We drew attention that many phthalates are not completely removed during the conventional wastewater treatment processes and often require an additional complex combination of technologies. Maximum wastewater cleaning efficiency (85–95%) depends on phthalates specificity and is achieved with advanced cleaning methods. However, the solutions to the problems of phthalate’s presence and removal from wastewater are often addressed at the scientific research level. Because of the modernisation and operation of advanced technologies, the cost can increase by 5–25%. As a result, some European countries face financial difficulties implementing advanced technologies. To make progress in cleaning up phthalates, the EU is likely to continue maintaining and upgrading existing wastewater systems.

The study aimed to analyze the effects of extracts made from buckwheat grain, hulls, and bee products (propolis, bread, and pollen) and extraction solvents on the growth of microfungi on a medium and on buckwheat, wheat, oat, and maize grain. Research findings suggest that bioactive compounds contained in buckwheat grain reduced the amount of Fusarium spp. in the grain kept in the antifungal extract for 90 min at 25°C temperature. Buckwheat hull extract was more effective in inhibiting mycelial growth of mycotoxin‐producing Fusarium culmorum and Fusarium graminearum compared with buckwheat grain extract (13%–50% and 14%–36%, respectively). The antifungal activity of extracts of bee products did not depend on the content of phenolic compounds in them; however, it depended on the grain species treated. After treatment of oat, wheat, and maize grain with bee product extracts, the lowest concentration of microfungi was identified on oat grain. More significant analysis results were obtained for the samples where ethanol solvent had been used for the preparation of extracts.

The United Nation’s Food and Agriculture Organisation have indicated that higher contamination of agricultural produce with mycotoxins is associated with the alterations in the weather conditions. The aim of the current study was to quantify mycotoxin contamination on buckwheat grain at early and complete ripening stages and to estimate the effects of the weather conditions on mycotoxin occurrence as well as to consider natural measures that could potentially reduce mycotoxin contamination in buckwheat products. Mycotoxins deoxynivalenol (DON), T-2 toxin (T-2), zearalenone (ZEA), aflatoxin B₁ (AFB₁), ochratoxin A (OTA) were analysed in fully ripe buckwheat grain in 2013 and at early ripening stages in 2014 and 2015. The field trials of buckwheat were set up at the Perloja Experimental Station, Lithuanian Research Centre for Agriculture and Forestry. The least concentrations of the investigated mycotoxins in buckwheat grain were found in 2013. Particularly high concentrations of AFB₁ (up to ~72 μg/kg) were identified in buckwheat grain at early ripening stages in 2014 and 2015. It is likely that buckwheat grain were contaminated with AFB₁ under favourable weather conditions, which were uncharacteristic of Lithuania’s climate in 2014 and 2015: hot weather and drought prevailed during the buckwheat flowering and ripening stages. However, such meteorological conditions were less favourable for the synthesis of DON, T-2, ZEA and OTA mycotoxins in buckwheat grain. The high AFB₁ contents found in grain question the quality of buckwheat products. Hulls were 10-fold more contaminated with AFB₁ than grain, which suggests that they serve as a protective shield against buckwheat groat, bran and flour contamination with this mycotoxin. Phenolic compounds were found to decrease the risk of mycotoxin occurrence in grain: with increasing concentrations of rutin, quercetin and total phenolics content in hulls and grain samples, the contents of trichothecene mycotoxins were significantly (P<0.05) lower.