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The value of honey as a natural food product is influenced by its pollen content, with the dominant type of pollen conferring specific medicinal properties. The present study examines the pollen spectra of 31 honeys from urban (linden, acacia, polyfloral, honeydew) and rural (rape, acacia, polyfloral, honeydew) apiaries in Poland. The pollen in content in honey ranged from 0.2 to 88 %. In total, 76 plant taxa were identified, 21 of which were assigned to forms A, B and C. Higher pollen grain content and a greater diversity of honey plant taxa were found in the urban honey, particularly polyfloral honey; this could be attributed to the rich variety of plants found in urban green areas compared to rural areas ones.

The objective of the study was to compare the effect of calcium peroxide and citric acid on the activity of acid phosphatase (ACP), alkaline phosphatase (ALP), and dehydrogenases (DHA) in uncontaminated soil and soil contaminated with petrol. The experiment was carried out on samples of loamy sand under laboratory conditions. Petrol was introduced to soil samples at a dose of 0 and 50 g·kg 1 DM, as well as calcium peroxide or citric acid at a dose of 0, 50, 100, or 150 mg·kg 1 DM. The humidity of the samples was brought to 60% maximum water holding capacity, and the samples were incubated at 20°C for 8 weeks. Enzyme activity was determined on days 1, 14, 28, and 56. The obtained results demonstrated that the addition of calcium peroxide and citric acid did not result in significant changes in the activity of the determined enzymes in uncontaminated soil. However, it was observed that the application of calcium peroxide, particularly at the dose of 150 mg·kg 1 DM, largely alleviated the impact of petrol on the enzymatic activity of the soil contaminated with petrol. Moreover, among the determined enzymes, the activity of DHA was found to be the best indicator of the effect of calcium peroxide on the soil ecosystem.

The objective of the present study was to compare the effect of rhamnolipids on the microbial biomass content and the activity of dehydrogenases (DHA), acid phosphatase (ACP), alkaline phosphatase (ALP), and urease (URE) in soil contaminated with two types of coal tar creosote: type C and type GX-Plus. The experiment was carried out on samples of sandy clay loam under laboratory conditions. Coal tar creosote was added to soil samples at a dose of 0 and 10 g·kg−1 DM, along with rhamnolipids at a dose of 0, 10, 100, and 1000 mg·kg−1 DM. The humidity of the samples was brought to 60% maximum water holding capacity, and the samples were incubated at 20°C. Microbial and biochemical parameters were determined on days 1, 7, 21, and 63. The obtained results demonstrated that the addition of rhamnolipids did not result in any significant changes in the activity of the determined parameters in the uncontaminated soil. However, it was observed that the application of these biosurfactants, particularly at the dose of 1000 mg·kg−1 DM, largely decreased the effect of coal tar creosote on the determined parameters. Moreover, the microbial biomass and the activity of ALP and URE were found to be the best indicator of bioremediation of soil contaminated with coal tar creosote.

Celem podjętych badań było określenie wpływu selenu (na dwóch stopniach utlenienia: +IV i +VI) na pojemność antyoksydacyjną gleby lekkiej zanieczyszczonej benzyną oraz olejem napędowym. Zastosowana w doświadczeniu gleba charakteryzowała się składem granulometrycznym piasku gliniastego oraz zawartością węgla organicznego 8,7 g·kg-1. Do części ziemistych wprowadzono w różnych kombinacjach benzynę lub olej napędowy w ilości 1 i 5% oraz H2SeO3 i H2SeO4 w ilości 0,05 mmol Se·kg-1. W okresie 35 dni w odstępach tygodniowych oznaczono pojemność antyoksydacyjną gleby w ekstraktach metanolowych oraz alkalicznych. Zanieczyszczenie gleby substancjami ropopochodnymi wpłynęło na zmniejszenie pojemności antyoksydacyjnej gleby. Natomiast wprowadzenie selenu spowodowało wzrost pojemności antyoksydacyjnej ekstraktów - w przypadku gleby niezawierającej substancji ropopochodnych efekt ten w większym stopniu uwidocznił się dla selenu na stopniu utlenienia +VI, a w przypadku gleby zanieczyszczonej benzyną dla selenu na stopniu utlenienia +IV

The aim of this study is to determine the effect of the two glyphosate salts: isopropylamine and potassium (contained in preparations Roundup) on the activity of phosphodiesterase and phosphotriesterase in the soil. The experiment was carried out in the laboratory conditions on two soil types: loamy sand (Corg 8.70 g·kg−1, pHKCl 6.39) and sandy loam (Corg 10.90 g·kg−1, pHKCl 6.81). Two glyphosate salts (isopropylamine and potassium) in dosage of 0, 1 and 100 mg·kg−1 were applicate into soils. Phosphodiesterase and phospotriesterase activities in soils were determined spectrophotometrically on days 1, 7, 14, 28, 56 and 112. The obtained results were converted with respect to the enzyme activities in the control soil (assuming it to be 100%) and given as percent of inhibition. The results were shown as environmental danger zones graphs. Obtained results showed that glyphosate salts application has primarily resulted in inhibition of phosphodiesterase activity, and stimulation of phosphotriesterase activity in soils. Soil type and kind of glyphosate salt affect the interaction of herbicide with phosphodiesterase and phosphotriesterase activities. The observed changes in the phosphodiesterase and phosphotriesterase activities caused by the addition of both glyphosate salts were located on environmental danger zones graphs in the range of negligible or acceptable values, which may indicate a low impact of herbicide on measured enzymes.

In this study, the effect of irrigation and anions introduced in the form of Mg(NO3)2, MgCO3 and MgSO4, which are biochemical indices of soil quality. Two laboratory experiments using complete randomisation were performed. First, one-factor experiment was carried out in triplicate. In this experiment, anion introduced with magnesium salt was the factor. The second experiment also was carried out in triplicate. In this experiment, the soil column for laboratory investigations of irrigated soil was used, anion introduced with magnesium salt was the first factor, and thickness of the soil layer was the second factor. The prepared material was irrigated nine times. In soil samples, the activity of dehydrogenases, proteases, alkaline phosphatase, amylase, and catalase was assayed. Based on these results, the biological index of fertility and enzyme activity number were calculated.

The aim of study was to determine the impact of three different biogas fermentation residues on some chemical and biochemical characteristics in sandy soil. The laboratory experiment was carried out on loamy sand. Residues were added to soil samples in the forms of pulp, drought, and granulate at dosages of 10, 50, and 100 g·kg-1. The reference was the soil sample without residues. On day 28, the content of macroelements and heavy metals was determined. In addition, on days 1, 7, 14, 28, and 56, the content of biomass and the activities of some hydrolases and oxidoreductases were assayed. Results showed that the application of all fermentation residues caused an increase in most of the chemical parameters. The highest impact on pH and the content of Ctot, Ntot, Stot, K, and P was observed in the soil treated with granulate, whereas the increase in the content of heavy metals was the highest after the drought application. The effect of biogas fermentation residues on all hydrolases and o-diphenol oxidase activities was mostly significant, but depended on the kind of residues and the day of experiment. Biomass content and the activity of dehydrogenase were increased in the whole experiment.

Survival of microorganisms in soils from treatment facility and landfill of wooden railway sleepers contaminated with creosote oil as well as in two types of soils with different content of organic carbon, treated with creosote oil vapors, was assessed. Microbiological assays including determination of: the biomass of living microorganisms method and the number of proteolytic, lipolytic and amylolytic microorganisms were carried out under laboratory conditions. Chromatography analysis of the soil extract from railway sleepers treatment facility was performed using GC/MS. The highest biomass and the number of tested microorganisms were determined in soils from wooden railway sleepers landfill, while the lowest in soil from the railway sleepers treatment facility. Vapors of creosote oil, regardless of the soil type, significantly increased only the number of lipolytic bacteria.

Due to advances in the industrial development of light-emitting diodes (LEDs), much research has been conducted in recent years to get a better understanding of how plants respond to these light sources. This study investigated the effects of different LED-based light regimes on strawberry plant development and performance. The photosynthetic pigment content, biochemical constituents, and growth characteristics of strawberry plants were investigated using a combination of different light intensities (150, 200, and 250 μmol m−2 s−1 ), qualities (red, green, and blue LEDs), and photoperiods (14/10 h, 16/8 h, and 12/12 h light/dark cycles) compared to the same treatment with white fluorescent light. Plant height, root length, shoot fresh and dry weight, chlorophyll a, total chlorophyll/carotenoid content, and most plant yield parameters were highest when illuminated with LM7 [intensity (250 μmol m−2 s−1 ) + quality (70% red/30% blue LED light combination) + photoperiod (16/8 h light/dark cycles)]. The best results for the effective quantum yield of PSII photochemistry Y(II), photochemical quenching coefficient (qP), and electron transport ratio (ETR) were obtained with LM8 illumination [intensity (250 μmol m−2 s−1 ) + quality (50% red/20% green/30% blue LED light combination) + photoperiod (12 h/12 h light/dark cycles)]. We conclude that strawberry plants require prolonged and high light intensities with a high red-light component for maximum performance and biomass production. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effect of hydrogen sulfide on chilling injury (CI) of banana (Musa spp.) during cold storage (7C). It was observed that hydrogen sulfide application (2 mmol L1) markedly reduced the CI index and showed significantly higher chlorophyll contents, along with suppressed chlorophyll peroxidase and chlorophyllase enzyme activity. The treated banana fruits exhibited substantially higher peel lightness (L), along with significantly a lower browning degree and soluble quinone content. The treated bananas had substantially a higher endogenous hydrogen sulfide content and higher activity of its biosynthesis-associated enzymes such as D-cysteine desulfhydrase (DCD) and L-cysteine desulfhydrase (LCD), along with significantly lower ion leakage, lipid peroxidation, hydrogen peroxide, and superoxide anion concentrations. Hydrogen sulfide-treated banana fruits showed an increased proline content and proline metabolism-associated enzymes including ornithine aminotransferase (OAT), 11-pyrroline-5-carboxylate synthetase (P5CS), and proline dehydrogenase (PDH). In the same way, hydrogen sulfide-fumigated banana fruits accumulated higher endogenous g-aminobutyric acid (GABA) due to enhanced activity of glutamate decarboxylase (GAD) and GABA transaminase (GABA-T) enzymes. The hydrogen sulfide-treated fruits exhibited higher total phenolics owing to lower polyphenol oxidase (PPO) and peroxidase (POD) activity and stimulated phenylalanine ammonia lyase (PAL). The treated banana exhibited higher ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR), dehydroascorbate reductase (DHAR), monodehydroascorbate reductase (MDHAR), and superoxide dismutase (SOD) activity, along with higher glutathione (GSH) and ascorbic acid (AsA) concentrations and a significantly lower dehydroascorbic acid (DHA) content. In conclusion, hydrogen sulfide treatment could be utilized for CI alleviation of banana fruits during cold storage [ABSTRACT FROM AUTHOR]