Antioxidant activity, the content of total phenols and flavonoids in the ethanol extracts of Mentha longifolia (L.) Hudson dried by the use of different techniques

In this study, we have examined the yield of extracted substances obtained by means of extraction using 70 % ethanol (v/v), the content of total phenols and flavonoids, as well as the antioxidant activity of the extracts obtained from the samples of the herbs dried by means of different techniques. Wild mint Mentha longifolia (L.) Hudson was dried naturally in a laboratory oven at a temperature of 45 °C and in an absorptive low temperature condensation oven at 35°C. The highest yield of extracts was obtained from the naturally dried herbs and the lowest from the herbs dried in the low temperature condensation drying oven. The content of total phenols and flavonoids was determined by spectrophotometric methods with an FC reagent and by the complexation reaction with aluminium-chloride, respectively. The extract of the naturally dried herbs had the highest overall content of phenols (113.8±2.0 mg of gallic acid/g of the dry extract) and flavonoids (106.7±0.3 mg of rutin/g of the dry extract). The highest antioxidant activity determined by the FRAP and DPPH assay was determined in the extracts obtained from naturally dried herbs (2.76±0.15 mmol Fe2+/mg of the dry extract and EC50=0.022±0.001 mg/ml), while the lowest was obtained from the extracts of herbs dried in the laboratory oven (1.13±0.11 mmol Fe2+/mg of the dry extract and EC50=0.033±0.001 mg/ml). The HPLC-DAD analysis result show that the greatest content of phenolic compounds show extract obtained from naturally dried plant material. The dominant phenolic component in the all extracts is Kaempferol 3-O-glucoside. The content of all phenolic compound strongly depend on the drying conditions

Linking farmer and beekeeper preferences with ecological knowledge to improve crop pollination

1. Pollination by insects is a key input into many crops, with managed honeybees often being hired to support pollination services. Despite substantial research into pollination management, no European studies have yet explored how and why farmers managed pollination services and few have explored why beekeepers use certain crops. 2. Using paired surveys of beekeepers and farmers in 10 European countries, this study examines beekeeper and farmer perceptions and motivations surrounding crop pollination. 3. Almost half of the farmers surveyed believed they had pollination service deficits in one or more of their crops. 4. Less than a third of farmers hired managed pollinators, however most undertook at least one form of agri-environment management known to benefit pollinators, although few did so to promote pollinators. 5. Beekeepers were ambivalent towards many mass flowering crops, with some beekeepers using crops for their honey that other beekeepers avoid because of perceived pesticide risks. 6. The findings highlight a number of largely overlooked knowledge gaps that will affect knowledge exchange and co-operation between the two groups

The influence of tillage system on the wheat sowing quality

In agricultural production, sowing is one of the most important agro-technical operations that influence the quality of the product and yield. The crops sowing quality, including wheat, depends on properly prepared soil, that is, on the quality of soil cultivation. However, despite well-executed soil cultivation, satisfactory results cannot always be achieved if sowing is not done in an appropriate manner. The achieved depth of sowing affects the speed of sprouting, rooting, resistance of plants to low temperature and drought, intensity of budding, growth and development, and achieving the highest yield in certain conditions. In unfavorable agro-technical conditions, and especially in the conditions of dry farming, optimal conditions for high-quality sowing often cannot be ensured by applying the conventional method. Therefore, new cultivation and sowing systems are being applied in order to perform high-quality sowing in time. During the experiment, the influences of the tillage system and sowing method on the sowing depth and the depth of the formation of the tillering nodes were registered. The results of two-year study are given, where four methods of tillage were applied, namely conventional tillage at depths of up to 25 cm and three reduced tillage methods at different depths. Reduced cultivation with a discc harrrow was done at a depths between 8 and 12 cm, and reduced cultivation with rototiller was done at depths of 5-10 cm and 10-15 cm. During the tests, the sowing depth and the depths of the tillering nodes were determined by direct measuring of the knots positions of the analyzed plants. Furthermore, it was verified that depth of the knot has a significant effect on the resistance of wheat to low temperatures during winter and lack of moisture during summer droughts. Achieved results enable further optimization of applied cultivation and sowing systems

Efficiency of alfalfa hay mowing machines under the dryland conditions

This paper presents the tests results of three types of hay mowing machines (later in text: mowers), namely a self-propelled oscillatory mower-conditioner and two tractor-mounted mowers with oscillatory and rotary blades, used to mow alfalfa grown under dry land conditions in the region of central Serbia during three seasons in 2014, 2015 and 2016. Although characterized by older design, they are still commonly used at smaller and medium size farms in this region. Therefore, their optimal exploitation parameters are still of large importance for hay quality and production efficiency and sustainability. The exploitation parameters of all three mowers generally increased linearly with higher speeds, having high R2 values (over 0,8), with rare exceptions. The regression coefficients b clearly showed that the self-propelled mower-conditioner achieved maximum increase in production performance (b = 0,3606), compared with the oscillatory (b = 0,1158) and rotary mowers (b = 0,1414). Mower design had a significant (p ≤ 0,001) effect on cutting and chopping losses, production performance, and specific fuel consumption (p ≤ 0,05). The tests confirmed the superiority of the self-propelled mower over the two mowers aggregated with tractors

Bioaccessibility of Phenolic Compounds and Antioxidant Properties of Goat-Milk Powder Fortified with Grape-Pomace-Seed Extract after In Vitro Gastrointestinal Digestion

This study deals with the evaluation of the bioaccessibility and antioxidant properties of phenolic compounds from heat-treated skim goat-milk powder fortified with grape-pomace-seed extract, after in vitro gastrointestinal digestion. Ultra-high performance liquid chromatography coupled to diode array detection and mass spectrometry (UHPLC-DAD MS/MS) analysis confirmed the abundant presence of phenolic acids and flavan-3-ols in the grape-pomace-seed extract (SE) and heat-treated skim goat-milk/seed-extract powder (TME). After in vitro digestion of TME powder and recovery of total quantified phenolics, flavan-3-ols and phenolic acids were 18.11%, 24.54%, and 1.17%, respectively. Low recovery of grape-pomace-seed phenolics indicated strong milk protein–phenolic interactions. Electrophoretic analysis of a soluble fraction of digested heat-treated skim goat milk (TM) and TME samples showed the absence of bands originating from milk proteins, indicating their hydrolysis during in vitro gastrointestinal digestion. The digested TME sample had better antioxidant properties in comparison to the digested TM sample (except for the ferrous ion-chelating capacity, FCC), due to the presence of bioaccessible phenolics. Taking into account the contribution of the digestive cocktail, digested TME sample had lower values of total phenolic content (TPC), in vitro phosphomolybdenum reducing capacity (TAC) and ferric reducing power (FRP), compared to the undigested TME sample. These results could be attributed to low recovery of phenolic compounds. TME powder could be a good carrier of phenolics to the colon; thus, TME powder could be a promising ingredient in the formulation of functional food. © 2022 by the authors

New contributions of measurements in Europe to the global inventory of the stable isotopic composition of methane

Recent climate change mitigation strategies rely on the reduction of methane (CH4) emissions. Carbon and hydrogen isotope ratio (δ13CCH4 and δ2HCH4) measurements can be used to distinguish sources and thus to understand the CH4 budget better. The CH4 emission estimates by models are sensitive to the isotopic signatures assigned to each source category, so it is important to provide representative estimates of the different CH4 source isotopic signatures worldwide. We present new measurements of isotope signatures of various, mainly anthropogenic, CH4 sources in Europe, which represent a substantial contribution to the global dataset of source isotopic measurements from the literature, especially for δ2HCH4. They improve the definition of δ13CCH4 from waste sources, and demonstrate the use of δ2HCH4 for fossil fuel source attribution. We combined our new measurements with the last published database of CH4 isotopic signatures and with additional literature, and present a new global database. We found that microbial sources are generally well characterised. The large variability in fossil fuel isotopic compositions requires particular care in the choice of weighting criteria for the calculation of a representative global value. The global dataset could be further improved by measurements from African, South American, and Asian countries, and more measurements from pyrogenic sources. We improved the source characterisation of CH4 emissions using stable isotopes and associated uncertainty, to be used in top-down studies. We emphasise that an appropriate use of the database requires the analysis of specific parameters in relation to source type and the region of interest. The final version of the European CH4 isotope database coupled with a global inventory of fossil and non-fossil δ13CCH4 and δ2HCH4 source signature measurements is available at 10.24416/UU01-YP43IN

Comunicación corta. Efecto del periodo de post-maduración sobre la germinación de semillas y crecimiento de plántulas en tres especies de festuca

After-ripening is a complex enzymatic and biochemical process resulting in the breakage of non-deep physiological dormancy. The experiment was set up to identify the minimum duration of storage after harvest for completion of afterripening in meadow (Festuca pratensis Huds.), tall (Festuca arundinacea Schreb.) and red fescue (Festuca rubra L.). The seeds were stored under ware-house conditions for 0, 30, 60, 90, 120, 150, 180, 210 and 240 days after harvest (DAH). After the storage periods, the seeds were tested for germination and the primary root length, shoot length and seedlings biomass were measured. The final counts in all three species amounted to 60-65% germination immediately after harvest, suggesting a medium level of embryonic dormancy. The after-ripening during storage improved the final germination in all three species with decreasing intensity. In meadow fescue, the final germination was significantly improved up to 150 DAH, while the seedling size did not change significantly. In tall and red fescue, after ripening significantly improved the final germination up to 120 DAH, while the seedling size variables reached maximum values after 150 DAH. The obtained data can serve for the determination of proper storage duration management between harvest and sowing (autumn/spring) of the tested fescue species under agro-ecological conditions of south-eastern Europe.La post-maduración es un proceso enzimático y bioquímico complejo que resulta en la rotura de la latencia fisiológicapoco profunda. El experimento se estableció para identificar el tiempo mínimo de almacenamiento después dela cosecha para la terminación de la post-maduración en festuca de prados (Festuca pratensis Huds.), festuca alta (Festucaarundinacea Schreb.) y festuca roja (Festuca rubra L.). Las semillas se almacenaron durante 0, 30, 60, 90, 120,150, 180, 210 y 240 días después de la cosecha (DAH). Después de los períodos de almacenamiento, se analizó la germinaciónde las semillas y se midieron la longitud de la raíz primaria, la longitud del vástago y la biomasa de las plántulas.Las tres especies tuvieron 60-65% de germinación inmediatamente después de la cosecha, lo que indica un nivelmedio de latencia de embriones. La post-maduración durante el almacenamiento mejoró la germinación final enlas tres especies, con una intensidad decreciente. En F. pratensis la germinación final aumentó considerablemente hasta150 DAH, mientras que el tamaño de plántulas no cambió significativamente. En F. arundinacea y F. rubra la postmaduraciónmejoró significativamente la germinación final hasta 120 DAH, mientras que el tamaño de las plántulasalcanzó valores máximos después de 150 DAH. Los datos obtenidos pueden servir para una gestión adecuada de laduración de almacenamiento entre la cosecha y la siembra (otoño/primavera) de las especies de festuca examinadasen las condiciones agro-ecológicas del sudeste de Europa

2009: Molecular characterization of the honeybee Apis mellifera carnica in

Abstract — The sequences COI-COII of the mitochondrial DNA region in honeybee from four geographically distant regions in Serbia (Vršac, Knjaževac, Kraljevo, and Vranje) are analyzed. The research was conducted on eight different, previously selected honeybee lines preserved (linear selection) in the four reprocenters for queen bees. All four studied honeybee lines differ in morphological and productive traits, each being specific for the corresponding region. In addition to analysis of the mtDNA sequences in Serbian honeybee, a comparative analysis of the phylogenetic group of so far known C2 haplotypes was also performed. The results revealed two novel polymorphic positions in the COI-COII mtDNA region, viz., h2 at position 3474 and l2 at position 3534 (a T nucleotide deletion in both cases) in honeybees from the regions of Vranje and Knjaževac, respectively. Two novel mtDNA haplotypes in the honeybee C2 phylogenetic group, together with C2I (the new polymorphic position l2 and G-A transition at position 3587) and C2J (the new polymorphic position h2), are described. Also, comparative analysis performed on sequences from GenBank data showed a high degree of similarity (similarity index = 99.4%) between the novel C2I mtDNA haplotype and an A. m. cypria haplotype originating from Turkey. Certain domestic Kranjska honeybee populations from Serbia represent an autochthonous gene pool that can be of great importance for further presentation of honeybee biodiversity. The present paper contributes to characterization of mtDNA in honeybee of Serbia

OLIVERA PETROVIĆ-OBRADOVIĆ AND

Abstract- Multivariate morphometric analysis was used to compare nine characteristics of 47 populations of Myzus persicae (Sulzer) originating from two host-plants, peach and tobacco, from 13 localities in 2004 and 34 localities in 2005, in Serbia and Montenegro. Multivariant discriminant analysis showed there to be a distinct discrimination between the populations from the peach and tobacco host-plants. The most important discrimination characteristics are the ultimate rostral segment length and processus terminalis length, which are greater in the aphids from tobacco than in those from peach. This is the first indication that in this part of Europe there are two subspecies: M. persicae (Sulzer) and M. persicae nicotianae Blackman