The growing demand for electricity, caused by dynamic economic growth, leads to a decrease in the available non-renewable energy resources constituting the foundation of global power generation. A search for alternative sources of energy that can support conventional energy technologies utilizing fossil fuels is not only of key significance for the power industry but is also important from the point of view of environmental conservation and sustainable development. Plant biomass, with its specific chemical structure and high calorific value, is a promising renewable source of energy which can be utilized in numerous conversion processes, enabling the production of solid, liquid, and gaseous fuels. Methods of thermal biomass conversion include pyrolysis, i.e., a process allowing one to obtain a multifunctional product known as biochar. The article presents a review of information related to the broad uses of carbonization products. It also discusses the legal aspects and quality standards applicable to these materials. The paper draws attention to the lack of uniform legal and quality conditions, which would allow for a much better use of biochar. The review also aims to highlight the high potential for a use of biochar in different environments. The presented text attempts to emphasize the importance of biochar as an alternative to classic products used for energy, environmental and agricultural purposes.

Honey composition is mainly affected by botanical origin, however geographical factors as well as beekeeping practice and storage conditions can also influence its quality. The aim of the study was to determine the impact of geographical origin on physicochemical quality and biological activity of honey. For this reason Polish and Slovak varietal honeys, including per each country: 10 multifloral, 5 tilia, 5 rape, 5 acacia and 5 forest were compared according to their physicochemical parameters (free acidity, pH, electrical conductivity, moisture content, and colour intensity), sugar profile, diastase activity, as well as antioxidant activity (DPPH and FRAP tests, as well as photochemiluminescence method). Moreover, total phenolics compounds and flavonoids content were determined. The most significant differences (P < 0.05) between Polish and Slovak counterparts were found for tilia while the lowest for rape honeys. The impact of geographical origin on overall quality of honey was proved by PCA statistical tool.

Is it possible to characterize the types of honey based on their chemical composition, their content of bioactive substances, and their physicochemical properties? The objective of this study was a comparative analysis of four types of honey from the Carpathian Foothills area, located in south-east Poland, based on the content of the main phenolic acids and proline, the mineral composition, and selected physicochemical properties. Most analyses, such as those of phenolic acids, sugars, and proline content, in honey samples were performed using chromatographic methods. These experiments demonstrated that honeydew honeys were the richest in phenolic acids, minerals, as well as oligosaccharides, compared to other honeys. Dark-colored honeys were characterized by the highest proline content. The dominant elements in all types of honey were potassium and calcium. The results of the present study show that analyses of specific phenolic acids, minerals, proline, and sugar content, in combination with chemometrics analysis, may successfully differentiate between the biological origins of honey samples and allow the preliminary verification of the samples before performing time-consuming pollen analysis.

Waste biomass from plant production is an important raw material for producing energy from renewable sources. Capabilities and technologies of processing are still being improved and modernized in order to achieve the highest energy efficiency. This study assesses energetic properties of wheat straw, rapeseed, and willow. The material was subjected to heat treatment, i.e., torrefaction process at temperatures of 220, 260, and 300 °C for the duration of 60, 75, and 90 min. Measurements were performed to compare parameters of raw biomass and the torrefied products. The materials were examined and compared for the contents of moisture; biogenic elements N, C, and H; as well as calorific value, ash, and volatiles. Measurements were also performed to assess the composition of biomass in terms of particle sizes. Analysis of the results made it possible to determine optimal parameters for carrying out the torrefaction process. The use of the torrefaction process made it possible to obtain a material with an increased calorific value by more than 20%, and a 2–3 times higher content of elements in the powdered material, as well as to improve the grinding of the material. This information will enable the development of biomass thermal treatment technologies towards the use of waste biomass from agricultural production.

The aim of this paper was to analyze selected physicochemical properties and the pro-health potential of wines produced in southeastern Poland, in the Subcarpathian region, and commercial Carlo Rossi wines enhanced with cowslip (Primula veris L.). This study used ultra-performance reverse-phase liquid chromatography (UPLC)-PDA-MS/MS to perform most of the analysis, including the polyphenolic compounds and saponin content in wines enriched by Primula veris L. The initial anthocyanin content in Subcarpathian (Regional) red wine samples increased four times to the level of 1956.85 mg/L after a 10% addition of Primula veris L. flowers. For white wines, a five-fold increase in flavonol content was found in Subcarpathian (Regional) and wine samples, and an almost 25-fold increase in flavonol content was found in Carlo Rossi (Commercial) wine samples at the lowest (2.5%) Primula veris L. flower addition. Qualitative analysis of the regional white wines with a 10% Primula veris L. flower enhancement demonstrated the highest kaempferol content (197.75 mg/L) and a high quercetin content (31.35 mg/L). Thanks to wine enrichment in triterpenoid saponins and in polyphenolic compounds from Primula veris L. flowers, which are effectively extracted to wine under mild conditions, both white and red wines can constitute a highly pro-health component of diets, which is valuable in preventing chronic heart failure.

The conversion of raw honey into powder can increase its usage in food industry but the health properties of obtained powder in relation to chemical composition of honey have been not studied since now. The aim of the study was to check the influence of botanical origin of honey on the quality of honey powder produced by spray drying method. Nine honey samples: honeydew (3), multifloral (3) and acacia (3) were transformed into honey powder using DC1500 dryer (Unimach, China). Analysis of honey powders and comparatively raw honeys covered: physicochemical parameters (moisture content, titratable acidity, pH, electrical conductivity, sugar profile (HPLC) and calorific value), bioactive compounds determination (antioxidant activity (DPPH and FRAP tests), phenolic compounds, mineral composition (ICP-OES) as well as microbiological purity and antibacterial activity. The experiments have shown that honeydew honey powder was characterized by the strongest antioxidant activity and the richest mineral composition, whereas the weakest properties for acacia honey were observed. Moreover, sugar profile of obtained powders was similar to raw honey. It was found that the quality of honey powder was directly dependent on the quality of raw honey. ARTICLE INFO

Coumarin is a plant secondary metabolite responsible for the health-promoting properties of the Melilotus officinalis herb used in traditional medicine in the treatment of lymphedema and chronic venous diseases. The aim of this study was to analyze the possibility of honey enrichment with coumarin derived from sweet clover (Melilotus) in two different ways: herb honey and herb-infused honey production. Herb honey was obtained by feeding bees with sugar syrup enriched with a M. officinalis herb water infusion, whereas herbal macerates in multifloral honey were prepared with crushed flowers (fresh and dried) of M. officinalis and Melilotus albus at 20 °C in dark place for 6 months. Melilotus albus nectar honey (n = 14) was used as control. Using HPLC analysis, the highest content of coumarin (from 41.33 to 137.89 mg/kg) and its precursor o-coumaric acid (from 6.57 to 25.15 mg/kg) in M. officinalis flowers-infused honey were found. Herb honey contains 4.48 mg/kg coumarin and for the first time, this compound was determined in nectar honey from Polish M. albus honey (0.05 to 0.88 mg/kg). The addition of Melilotus flowers enhanced antioxidant activity (measured by FRAP, DPPH and PCL methods) of infused-honey in comparison to multifloral honey (control) and herb honey. The coumarin and o-coumaric acid were weakly correlated with antioxidant activity. It was found that only herb-infused honey can be proposed as the natural safe remedy for venous diseases prevention.

Our experiments may help to answer the question of whether cowslip (Primula veris L.) is a rich source of bioactive substances that can be obtained by efficient extraction with potential use as a food additive. A hypothesis assumed that the type of solvent used for plant extraction and the individual morphological parts of Primula veris L. used for the preparation of herbal extracts will have key impacts on the efficiency of the extraction of bioactive compounds, and thus, the health-promoting quality of plant concentrates produced. Most analysis of such polyphenolic compound contents in extracts from Primula veris L. has been performed by using chromatography methods such as ultra-performance reverse-phase liquid chromatography (UPLC−PDA−MS/MS). Experiments demonstrated that the most effective extraction agent for fresh study material was water at 100 °C, whereas for dried material it was 70% ethanol. The richest sources of polyphenolic compounds were found in cowslip primrose flowers and leaves. The aqueous and ethanol extracts from Primula veris L. were characterized by a quantitatively rich profile of polyphenolic substances, and a high antioxidative potential. Selective extraction with the use of mild conditions and neutral solvents is the first step to obtaining preparations from cowslip primrose with a high content of bioactive substances.