Effect of different olive oils on bile excretion in rats fed cholesterol-containing and cholesterol-free diets

The mechanism of the hypocholesterolemic effect of olive oils was investigated in 60 Wistar rats adapted to cholesterol-containing and cholesterol-free diets. The rats were divided in six diet groups of 10. The control group was fed only basal diet (BD), which contained wheat starch, casein, cellulose, and mineral and vitamin mixtures. For the five other groups, 10 g/100 g virgin (virgin group) or lampante (lampante group) olive oils, 1 g/100 g cholesterol (chol group), or both cholesterol and oil (chol/virgin and chol/lampante groups) were added to the BD. The experiment lasted 4 weeks. Before and after the experiment the bile was collected, and its flow and biliary bile acids and cholesterol concentrations were registered. Plasma lipids, liver cholesterol, plasma antioxidative potential (TRAP), fecal output, fecal bile acids, and fecal cholesterol excretion were measured. Groups did not differ before the experiment. After the experiment significant hypocholesterolemic and antioxidant effects were registered mainly in groups of rats fed cholesterol-containing diets supplemented with both olive oils (chol/virgin and chol/lampante). Significant increases in the bile flow and in the bile cholesterol and bile acids concentrations were observed (19.2% and 16.9%, 30.5% and 18.2%, and 79.6% and 45.6% for the chol/virgin and chol/lampante groups, respectively). Also, significant increases of the fecal output and fecal excretion of bile acids and cholesterol in rats of these groups were found. In conclusion, olive oils positively affect plasma lipid metabolism. The hypocholesterolemic effect of olive oils is genuine and is most likely mediated through increases in bile flow and biliary cholesterol and bile acids concentrations and subsequent increases in their fecal excretion.     

Impact of feed ration on growth and the results of sterlet,Acipenser ruthenus L., artificial reproduction

In the study the effects of artificial reproduction of sterlet (Acipenser ruthenus) fed different feed ration were compared. Three doses of feed were used: 1.0%, 0.75% and 0.5% of the fish biomass per day. The results indicate that the feed rations for fish used for caviar production or breeding material should differ. The optimal ration for the quality of sex products and progeny was 0.75% of the fish biomass, whereas in view of the number of maturing fish, the better ration was that of 1% of the fish biomass. In group fed 0.75% of the fish biomass per day the highest GSI value, the largest eggs and hatch and the highest survival to the hatch were noted. The feed ration of 0.5% of the fish biomass was too low, as indicated by the low parameters of eggs obtained, their survival and the smallest number of mature and ovulating females. These results can provide direction for the creation and exploitation of spawner stocks as well as for other sturgeon species cultured under controlled conditions.     

Viability of diploid and triploid larvae of Siberian sturgeon and bester hybrids

The aim of the present study was to produce Acipenser baeri× (Huso huso×Acipenser ruthenus) hybrids in a diploid and triploid state and to study their viability in comparison with the A. baeri from the fish farm stock. A heat shock (37°C) in the 18th minute after fertilization was applied to induce triploidy. The survival rate and the ploidy level of the hybrids obtained were studied. The mortality of triploid hybrids was approximately twice as high as the mortality of diploid hybrids. No significant difference in the survival rate between Siberian sturgeon and their diploid hybrid with bester was noted. Cytogenetic analysis was performed by preparing chromosomes from the gill epithelium. The results showed that all studied fish from the heat‐shocked group were triploid.     

Presence of Caffeic Acid in Flaxseed Lignan Macromolecule

Phenolic compounds were extracted from defatted flaxseeds using ethanol-dioxane (1:1, v/v). The crude extract obtained was purified using Amberlite XAD-16 column chromatography with water and methanol as mobile phases. RP-HPLC and SE-HPLC showed a lignan macromolecule (LM) as a dominant phenolic compound in the purified extract. After the alkaline hydrolysis of LM caffeic acid glucoside (CaAG) was isolated using a semi-preparative HPLC and its structure was confirmed by LC-ESI-MS. In LM of the investigated flaxseed, one molecule of caffeic acid corresponded with five molecules of p-coumaric acid and two molecules of ferulic acid. The presence of caffeic acid in the lignan molecule might be very beneficial due to its high antioxidant activity.     

The effect of soil type and farm size on the variability of weed infestation in maize (Zea mays L.) fields in the south-west region of Poland

Weeds are a primary factor limiting maize yield. Their occurrence and abundance are affected considerably by environmental factors and farming practices. The variability of weed number in maize depending on the soil type and farm size was investigated. Farms of different sizes vary in farming practices, which affects weediness. Based on this assumption, farm size was considered as indirect factor affecting weed abundance. An investigation of 45 farms that differed in size (5–15 ha, 15–50 ha, >50 ha) and soil type (chernozem, distric cambisol, haplic luvisol) was conducted. Thirteen dominant weed species persistently occurring in maize fields in south-western Poland were examined. Regardless of the soil type and farm size, the most abundant weed species were Echinochloa crus-galli and Chenopodium album. In addition to these species, the most numerous weeds on chernozems were Setaria viridis and Solanum nigrum, while on haplic luvisols and distric cambisols, the most numerous were Viola arvensis and Elymus repens. Additionally, on haplic luvisols, Anthemis arvensis was abundant. Small farms were stronger infested by weeds than large farms due to the implementation of extensive weed-supressing practices, especially low herbicide use. Soil type affected the number of weeds to a greater extent than did farm size.     

Field-scale variability of topsoil dehydrogenase and cellulase activities as affected by variability of some physico-chemical properties

We have studied spatial field-scale variability of soil dehydrogenase (DH) and cellulase activities (CEL) and their relationship with variability of some physico-chemical properties at the surface horizon of the agricultural field. Soil samples were collected at 50 points from the upper 20 cm of soil. The activity of DH ranged between 0.77 and 1.5 μM TPP·g⁻¹·h⁻¹ while CEL activity ranged from 0.8 to 1.94 μM glucose·g⁻¹·24 h⁻¹. Concentrations of C_ORG and TN varied from 8.5 to 31.7 g·kg⁻¹ and from 0.94 to 3.56 g·kg⁻¹, respectively. The soil data showed that spatial variability and semivariograms describe spherical and linear models with the nugget effect (DH, CEL, C_ORG and TN). Dehydrogenase activity was in the strong variability class, while cellulase activity was situated in the week variability class. Both C_ORG and TN concentrations and pH_KCl values were strongly spatially dependent with the percentage of total variance (sill) presents as nugget variance ranging from 8.9% to 16.1%. Kriged maps displayed the lowest values of CEL activities in the north-east of the area, while the south area showed the highest CEL activity. The DH activity values were irregularly distributed in the surface horizon of the studied soil and this behaviour did not correspond with the spatial distribution of other properties.     

Effect of the chemical composition of industrial dusts on forest floor organic matter accumulation

The influence of dusts from aluminium (AP), zinc and lead (ZP1, ZP2), sintering (SP) and power (PP) plants on organic matter accumulation on the forest floor of a mixed oak-pine forest was studied in Niepo?omice Forest near Kraków, Poland. An artificial application of the dusts on experimental plots was used corresponding to 100, 500, 1000, 2000, and 5000 t km^?2. Increased organic matter accumulation was observed 5 yr following the addition of AP, ZP1 and ZP2 dusts, while SP and PP dusts at levels > 100 t km^?2 caused a slight decrease in litter accumulation. Statistical analysis indicated that Cd, Mn, Pb and Zn present in industrial dusts were responsible for the increase in litter accumulation, while some nutrients (e.g. K, Mg, Na) contained in the dusts might decrease organic matter storage to some extent.     

Effect of fluazifop-p-butyl treatment on pigments and polyamines level within tissues of non-target maize plants

Fluazifop-p-butyl (FL) is one of the most popular graminicides from arylophenoxypropionate group. These herbicides act as inhibitors of acetyl-CoA carboxylase (ACCase) that catalyzes the formation of malonyl-CoA during metabolism of lipids and/or of some secondary compounds. On the other hand arylopropionates and cyclohexanediones cause phytotoxic effects by stimulating free-radicals generation and causing oxidative stress in susceptible plants. However, the importance of disturbances in plant pigments and polyamines accumulation for this effect is not clear. The aim of this work is to quantify the phytotoxicity of FL to non target maize plant and to explain how photosynthetic pigments, anthocyanins (ANC) and polyamines participate in this interaction.