Biological Activity and Stability of Aeruginosamides from Cyanobacteria

Aeruginosamides (AEGs) are classified as cyanobactins, ribosomally synthesized peptides with post-translational modifications. They have been identified in cyanobacteria of genera Microcystis, Oscillatoria, and Limnoraphis. In this work, the new data on the in vitro activities of three AEG variants, AEG A, AEG625 and AEG657, and their interactions with metabolic enzymes are reported. Two aeruginosamides, AEG625 and AEG657, decreased the viability of human breast cancer cell line T47D, but neither of the peptides was active against human liver cancer cell line Huh7. AEGs also did not change the expression of MIR92b-3p, but for AEG625, the induction of oxidative stress was observed. In the presence of a liver S9 fraction containing microsomal and cytosolic enzymes, AEG625 and AEG657 showed high stability. In the same assays, quick removal of AEG A was recorded. The peptides had mild activity against three cytochrome P450 enzymes, CYP2C9, CYP2D6 and CYP3A4, but only at the highest concentration used in the study (60 µM). The properties of AEGs, i.e., cytotoxic activity and in vitro interactions with important metabolic enzymes, form a good basis for further studies on their pharmacological potential.     

Nutritional regulation of intestine morphology in larval cyprinid fish, silver bream (Vimba vimba)

The present study includes the evaluation of morphological changes in the digestive tract of larval, stomachless fish silver bream ( Vimba vimba ) fed with various diets – live Artemia nauplii, commercial feed Aglo Norse (NOR) and semi-purified formulated diets: casein–gelatin (CG), dipeptide-protein (50P), dipeptide (100P), no-arginine dipeptide diet (100Pw/oArg) and a free amino acid (FAA) mixture diet. The supranuclear area of enterocytes in the posterior intestine contained enlarged absorptive vacuoles in the FAA, 100P and 100Pw/oArg groups, compared with the remaining groups. Hepatocytes' cytoplasm in fish fed with FAA, 100P and 100Pw/oArg contained mainly glycogen, and no lipid vacuoles were found. Fish fed with 100Pw/oArg showed the lowest hepatocyte surface areas while in those fed with 50P, the largest nuclei diameters were observed. Fish fed with Artemia , NOR and CG diets showed significantly ( P <0.05) higher number of proliferating cells compared with the remaining groups. Chromogranin A staining showed endocrine-immunoreactive cells (CgA-IR) in the taste buds in the oral cavity and in the enterocytes' supranuclear areas of the anterior and posterior intestine. We conclude that the growth rate and histological examination of the digestive tract in the 50P group of silver bream showed no nutritional deficiency.     

New winter oilseed rape varieties – seed quality and morphological traits depending on sowing date and rate

Many studies have focused on research about impact of time and density of sowing on the agronomic characteristics of different crops. However, the number of studies investigating such a response on the qualitative composition of different types of winter oilseed rape varieties is still limited. The aim of the research was to determine the effect of sowing date and density on yield, protein and oil content and quality of winter oilseed rape varieties: open-pollinated, a typical hybrid of traditional type of growth and a new semi-dwarf hybrid, which biology and yielding have not been thoroughly established. This experiment was conducted applying four sowing dates (August 14, August 25, September 4, September 15), three winter oilseed rape cultivars (PR45D03 -semi-dwarf hybrid, PR46W31 – hybrid, Californium – open-pollinated) and four sowing rates (30, 40, 50, 60 seeds/m²). Among the compared sowing dates, August 25 proved to be optimal for yielding of the tested winter oilseed rape cultivars. Semi-dwarf variety contained less protein and glucosinolate in seeds, but more oil in comparison to other studied varieties (hybrid and open-pollinated). The yields did not differ significantly within a density of 40, 50, 60 seeds/m², so it is important result, especially for the agricultural practice.     

Development and characterization of wheat lines with increased levels of arabinoxylan

Improving the nutritional quality and health benefits of food has been of increasing interest globally over the last decade. Staple cereal foods are the major sources of dietary fiber and a recent study identified the Chinese wheat cultivar Yumai-34 as having unusually high levels of water-extractable arabinoxylan (WE-AX) and total arabinoxylan (TOT-AX) in flour. Crosses were therefore made between this variety and three Central European varieties (Lupus, Mv-Mambo, Ukrainka) and the physical properties (test weight, thousand-kernel weight, flour yield, kernel hardness), composition (protein, gluten, WEAX, total AX) and processing quality (gluten index, Zeleny sedimentation, Farinograph parameters) of the grain were compared for thirty-one breeding lines (F₇–F₉) and the four parents in a 3-year field experiment (2013–2015). Increases of 0.5% in the WE-AX content and 1% in the content of total AX content of the flour were achieved, with an improvement in dough properties. The thousand-kernel weight, protein content, gluten content, Zeleny sedimentation and water absorption of the flour also increased in many lines, while three of the lines had yields that were competitive with the official control varieties, making them suitable for registration.     

Potential involvement of rapeseed (Brassica napus L.) metallothioneins in the hydrogen peroxide‐induced regulation of seed vigour

Germination is a crucial process in crop plant life cycle that determines future yield. Hydrogen peroxide plays a significant role in both dormancy release and seed ageing. The potential of the rapeseed metallothioneins (BnMT1‐4) as reactive oxygen species scavengers was investigated. In the presence of H₂O₂, bacterial cells expressing BnMT1‐4 had higher growth rate than control cells. However, such effect was not observed in an oxidative stress oversensitive yap‐1Δ yeast mutant strain expressing BnMT1‐4. Next, it was shown that H₂O₂, up to 100 and 10 mM, promotes rapeseed germination rate and seedling growth, respectively. Moreover, it was demonstrated that in seeds germinating in the presence of H₂O_2, the expression of seed‐specific BnMT4 decreases to a high extent in a dose‐ and time‐dependent manner. It was shown that the decline in BnMT4 mRNA level, accelerated by up to 10 mM H₂O₂ treatment, correlates positively with increased rapeseed germination and early growth, underscoring the plausible role of BnMT4 as a H₂O₂ scavenging protein that level has to be downregulated in conditions where the compound is needed. Finally, it was demonstrated that H₂O₂ could be used as a priming agent of rapeseeds.     

Weak competitive ability may explain decline of Taxus baccata

Context

Taxus woodlands suffer from a lack of natural regeneration across its whole distribution range.

Aims

In Knyazhdvir Reserve in Ukraine Taxus baccata primarily competes with Abies alba. It has been assumed that in the conditions of deep shade, yews have a greater competitive advantage than firs.

Methods

To verify this hypothesis, a plot with both species growing under the canopy was established. Wood samples were taken from 20 trees of T. baccata and 20 trees of A. alba.

Results

There were no differences in the mean tree-ring width, height and age between both species. Due to a lack of spatial separation of both species, yews and firs inhabited the same area in the analysed plot. Fir seedlings (up to 0.5?m) were recorded to grow under yew saplings (above 0.5?m), but the inverse situation of yew seedlings growing under fir saplings was not seen.

Conclusion

Seedling distribution, tree-ring growth rate, possibility of growth of fir seedlings under yew saplings and greater potential growth suggested that fir was predisposed to having the competitive edge over yew. Our results may confirm the hypothesis that T. baccata has a restricted distribution because of weak competitive abilities and can exist only in habitats where faster growing species are absent. The results call into question the prevailing opinion that human influences are the principal cause for the decline of T. baccata.     

Detection of runs of homozygosity in conserved and commercial pig breeds in Poland

Runs of homozygosity (ROH) are continuous segments of the genome that arose as a result of inbreeding, resulting in the inheritance of identical haplotypes from both parents who shared a common ancestor. In the present study, we performed a detailed characterization and comparison of ROH in four pig breeds, including intensively selected Polish Landrace as well as native unselected animals of Puławska and two Złotnicka breeds (White and Spotted). We used a medium-density PorcineSNP60 BeadChip assay (Illumina) and cgaTOH software to detect ROH covering a minimum of 30 adjacent SNPs and maintaining a size over 1 Mb. By analysing ROH distribution and frequency across the genome, we also identified genomic regions with high ROH frequency (so-called “ROH hotspots”). The obtained results showed that the analysed conserved breeds were characterized by a higher ROH span and higher ROH-based inbreeding coefficients (F_ROH), which likely result from past population bottlenecks, increasing the overall inbreeding level within these populations. The analysis of ROH distribution across the genomes revealed the presence of both shared and breed-specific ROH hotspots. These hotspots, presumably representing genome regions under selection, overlapped with a variety of genes associated with processes connected with immune system functioning, reproduction, glucose homeostasis and metabolism. The genome regions with ROH hotspots overlapping in all analysed populations, located on SSC4 (51.9–55.9 Mb) and 13 (92.6–97.8 Mb), covered thirty-one different genes, including MMP16, SLC7A13, ATP6V0D2, CNGB3, WWiP1, RiMDN1 and CPNE3. These genes are primarily associated with biological regulation and metabolism, processes that could be responsible for the variety of the selected production and functional features.     

Giblets and abdominal fat of pomegranate seed oil fed chickens as a source of bioactive fatty acids

The aim of present study was to determine whether chickens’ (broilers Ross 308, n = 180, sex ratio 1:1) diet modification with different doses of grape or pomegranate seed oil will favourable change fatty acids and cholesterol content in selected giblets (liver and heart) or wastes (adipose tissue). It was also verify whether generated changes would make the giblets and wastes more valuable as dietary components or by-products for food industry. From 22 to 42 day of life, five diets were administered to chickens. Control grower diet (CON) contained 5% of soy oil, whereas in the experimental grower diets part of soy oil (1.5% or 2%) was replaced with specific amount of grape or pomegranate seed oil (GRAP 1.5; GRAP 2.0; POM 1.5; POM 2.0 respectively). Fatty acids and cholesterol content were determined with gas chromatography with flame-ionization detection. Pomegranate seed oil improved fatty acids profile more favourably than grape seed oil, which makes it a valuable additive in chickens’ feeding. Abdominal fat of pomegranate seed oil supplemented chickens appeared to be the richest sources of rumenic acid and n3 polyunsaturated fatty acids, which allows to suggest its use in manufacturing of meat products to obtain foodstuffs rich in those essential nutrients. In principal component analysis (PCA), two principal components: PC1 and PC2, which were enough to explain 29.91% of variance of initial variables, allowed to a good separation of chickens fed with both doses of pomegranate seed oil from animals from control and grape seed oil fed groups. Because poultry addresses all nutritional, institutional and consumer requirements, enrichment of giblets in rumenic acid by pomegranate seed oil incorporation into chickens’ diet may provide a valuable dietary source of bioactive fatty acids for consumers, especially of low-income countries.     

Measurement of in situ Phosphorus Availability in Acidified Soils using Iron-Infused Resin

A hybrid anion resin was tested for in situ phosphorus (P) availability measurement in soils of two stands recovering from acidification and having different P-sorption characteristics. The phosphate (P-PO₄) sorption capacity of the resin (before saturation) was 48 µmol g^?1. Sorption and elution were tested under P-PO₄ concentrations common in acidic soils (0–0.42 mmol l^?1) either with or without the presence of sulfate (0.2 mmol l^?1). The efficiency of P-PO₄ sorption was independent of the sulfate and was 100 ± 0.2% (n = 56, ± SD). The P-PO₄ recovery stabilized after six elution steps (each: 50 ml of 0.5 M sodium hydroxide, resin/solution 5:1). The efficiency of P-PO₄ recovery was 80 ± 7% and was used to evaluate field measurements. We determined the amount of P-PO₄ in the field using resin bags in three consecutive years. The results indicate that bioavailable P is negatively related to the soil ability to retain P.