Application of Conjugated Polymer–Platinum Group Metal Composites as Heterogeneous Catalysts

Composites of polyaniline (PANI) or polypyrrole (PPy) doped with chloride ions and Pt or Rh particles were prepared by chemical reduction of metal ions conducted in the presence of the polymers. Based on X-ray diffraction studies it was established that the composites contained metal nanoparticles (5–9 in size). However, according to SEM investigations metal particles were agglomerated (40 nm–1.1 μm in size). Redox activity of the composites in the catalytic isopropyl alcohol conversion was ca. ten times higher than the acid–base one. Pt dispersed in polymer matrices showed higher catalytic activity than Rh. PPy doped with chloride ions had a promoting effect on the activity of Pt catalysts.     

Comparative Study of the Genetic and Biochemical Variability of Polyscias filicifolia (Araliaceae) Regenerants Obtained by Indirect and Direct Somatic Embryogenesis as a Source of Triterpenes

Polyscias filicifolia (Araliaceae) is broadly used in traditional medicine in Southeast Asia due to its antimicrobial, immunomodulating and cytotoxic activities. The main groups of compounds responsible for pharmacological effects are believed to be oleanolic triterpene saponins. However, Polyscias plants demonstrate relatively slow growth in natural conditions, which led to applying a developing sustainable source of plant material via primary (PSE), secondary (DSE) and direct somatic embryogenesis from DSE (TSE). The AFLP and metAFLP genotyping resulted in 1277 markers, amplified by a total of 24 pairs of selective primers. Only 3.13% of the markers were polymorphic. The analysis of variance showed that the PSE and TSE regenerants differed only in terms of root number, while the DSE plantlets differed for all studied morphological characteristics. Further, the chemical analysis revealed that oleanolic acid (439.72 µg/g DW), ursolic acid (111.85 µg/g DW) and hederagenin (19.07 µg/g DW) were determined in TSE regenerants. Our results indicate that direct somatic embryogenesis ensures the production of homogeneous plant material, which can serve as a potential source of triterpene compounds. Plants obtained via somatic embryogenesis could also be reintroduced into the natural environment to protect and preserve its biodiversity.     

Mesoporous niobosilicates serving as catalysts for synthesis of fragrances

Niobium-containing siliceous-MSU-X mesoporous molecular sieves have been prepared according to an original pathway by the reaction between low-cost niobium species (ammonium trisoxalate complex of niobium (V)), silica precursor (tetraethyl orthosilicate), and biodegradable surfactant in strong acidic, acidic or almost neutral medium. The selective oxidation of several terpenes and terpenoids (geraniol, limonene, α-terpineol) using hydrogen peroxide as an oxidant agent over novel Nb-catalysts is studied in this work. A variety of (Nb)MSU-X and (Ru,Nb)MSU-X materials prepared under different conditions has been employed (supermicroporous/mesoporous molecular sieves) for this purpose. The structure–function relationships in these catalysts are reported.     

Influence of High Magnetic Field Annealing on Aicrostructure of Pulse-Electrodeposited Nanocrystalline Co-Ni-P Films

The effects of high magnetic field armealihng on the morphology and texture of pulsed-electrodeposited Co-Ni-P films were investigated by field emission scanning electronic microscopy(FE-SEM),atomic force microscopy(AFM)and X-ray diffraction(XRD).The as-deposited film with cluster structural on a rough surface changed into non-uniform and bigger nanocrystalline during the no-field annealing due to a recrystallization process.Post-deposition annealing under a magnetic field favored to form a more homogeneous surface with smaller grain size and lower roughness.The magneto-induced a mixed phase structure including fcc-Ni,hcp-Co and fcc-CoNiP appeared in the case of the films annealed at a 9T magnetic field.The possible overlapping effects such as diffusion and recrystallization obtained by the magnetic field annealing on the morphology evolution and on the phase transformation in the films were interpreted.     

Effect of flaxseed supplementation of dairy cows' forage on physicochemical characteristic of milk and Raclette cheese

The composition of bovine milk depends on breed, lactation stage, age of cows and dietary factors. The effect of flaxseed supplementation of forage diet on the chemical composition of milk and the physicochemical and sensory characterisation of Raclette cheese were investigated in this study. As a result of diet supplementation, the proportion of saturated fatty acids in milk decreased and the content of α‐linolenic and oleic acids increased. Concerning the cheese samples, the hardness was significantly reduced due to the flaxseed supplementation, which can positively affect the quality of the cheese due to the diminished risk of crack formation. Sensory characteristics of melted Raclette cheese were not affected by the dietary treatments.     

Distribution of polychlorinated biphenyls, organochlorine pesticides and polybrominated diphenyl ethers in human umbilical cord serum, maternal serum and milk from Wielkopolska region, Poland

The levels of organochlorinated pesticides (OCPs): p,p'-DDT and its metabolites, hexachlorobenzene (HCB), hexachlorocyclohexane isomers (HCHs), chlordanes and their metabolites, and 18 polychlorinated biphenyl (PCB) congeners were measured in maternal serum, umbilical cord serum and human milk collected from 22 mothers living in the Wielkopolska region, Poland. Additionally, 11 polybrominated diphenyl ether (PBDE) congeners were measured in the human milk samples. p,p'-DDT and its major metabolite, p,p'-DDE, together with HCB, were found in all milk and serum samples. Median concentrations of p,p'-DDE in maternal serum, umbilical cord serum and milk were 343, 329 and 634ng/g lipid weight (lw). PCB congeners 138, 153 and 180 were the major congeners measured in all serum samples, while CB 170 was detected in 74% and 100% of umbilical cord and maternal serum, respectively. Except for CBs 74, 101 and 105, which had a detection frequency of 77%, 23% and 82%, respectively, all investigated PCB congeners were measured in all human milk samples. The median concentrations of sum PCBs in maternal serum, umbilical cord serum and milk were 79, 60 and 133 ng/g lw, respectively. A good correlation (Spearman R(S)>0.75, p<0.001) was found for major PCBs, p,p'-DDT and p,p'-DDE, between maternal and umbilical cord serum, while the correlation was weaker between milk and serum. The median of sum PBDEs in human milk was 2.0 ng/g lw (range 0.8 to 8.4), with BDE 47 being always the most abundant PBDE congener and, together with BDE 153, being present in all samples. In general, results found in the investigated group are at the low end of the concentration range measured in Europe.