Blackcurrant (Ribes nigrum L.) Seeds-A Valuable Byproduct for Further Processing.

The rational exploitation of byproducts is important from the point of view of their potential applicability in various fields. In this study, the possibility of further processing of blackcurrant seeds (BCs), which are a byproduct of fruit processing, was investigated. BCs were used as a material for the extraction of oil on a semi-industrial scale, and the residues were assessed in terms of their potential application in skin care products. Supercritical fluid extraction (SFE) using CO2 at pressures of 230 and 330 bar and extraction temperature of 40 °C was exploited for isolation of oil, and the products were characterised taking into account lipophilic constituents. After 120 min, the oil yields were 19.67% and 20.94% using CO2 at 230 and 330 bar, respectively, which showed that SFE was an effective method on a semi-industrial scale, taking into account the extraction yield. The oils had similar fatty acid compositions with a high percentage of linoleic acid (ca. 43%); however, tocopherols and carotenoids were most abundant in the oil obtained at 230 bar. It was also found that the composition of the SFE oils was comparable with that of cold-pressed oil, which shows that supercritical fluid extraction provides a high-quality product; therefore, it can be an alternative to cold pressing. Furthermore, the chemical compositions of the extracts from the oil isolation residues were established using UPLC-MS, and the impact of the extracts on human skin fibroblasts was assessed using the MTT and NR assays. The quantitative analysis revealed that the residues contained high amounts of polyphenolic acids, including gallic, protocatechuic, and hydroxybenzoic acid derivatives, as well as flavonoids, especially quercetin and kaempferol glucoside. Moreover, it was found that the extracts were nontoxic and exerted a stimulatory effect on cell metabolism. Therefore, they can be a valuable additive to natural plant-based cosmetics. Our results showed that blackcurrant seeds, regarded as a byproduct, can be a valuable material for further use.

Modeling and Optimization of the Isolation of Blackcurrant and Black Cumin Seeds Oils Using Supercritical Fluid Extraction.

Supercritical fluid extraction is a powerful analytical tool and it is willingly used by researchers for the isolation of various components from different matrices. In our study, the carbon dioxide in the supercritical state was used for the extraction of oils from blackcurrant and black cumin seeds. To determine the optimal conditions for the process (temperature, pressure and time), the method of statistical experiment planning and the Box-Behnken design was applied and the yield of the oils and the content of fatty acids (FAs) were taken into consideration. It has been found that an increase in pressure causes an increase in extraction yield (W), and an increase in temperature, both at constant pressure and time, does not significantly change the yield value. Optimal yield values were obtained for both materials under almost similar extraction parameters: 306 bar/ 43 min/ 50 °C (blackcurrant) and 282 bar/ 40 min/ 50 °C (black cumin). The influence of the above parameters (T, p, t) on the content of FAs in the extracts has a slightly different trend. The use of supercritical carbon dioxide for the extraction of blackcurrant and black cumin seeds allowed for high process yield and high-quality, rich in polyunsaturated fatty acids oils which can be used as a substrate or final product for industry.

The Influence of Polycaprolactone on Structural Changes of Dusts from Molding Sands with Resin-Based Binder before and after the Biodegradation Process.

Resin-based binders are one of the main materials used in foundry molding and core sands. This work adds to the research on self-curing sands with furfuryl resin, which dominates in the production of large-size castings. The work concerns the possibility of using biodegradable polymers as a component of resin-based binders. Biodegradable or partially biodegradable polymers are a group of materials which have an increasing level of importance in many areas of life and technology. This is mainly due to the increase in waste deposited in landfills, water and soil. This problem also concerns waste from the casting production process with the use of disposable molds with resin-based binders, which are mainly residues from their mechanical regeneration process. The aim of the research presented in this paper was to determine the effect of polycaprolactone (PCL) on the structure of post-regeneration dust from molding sands before and after the biodegradation process carried out in a water environment. Structure studies were carried out by Fourier transform infrared spectroscopy (FTIR) and the changes in the mass by TG/DTA-QMS analysis. The article also presents the results of the research of the morphology carried out by scanning electron microscopy (SEM) and the chemical oxygen demand index (COD) in water extracts of dust samples.

Effect of the Biodegradable Component Addition to the Molding Sand on the Microstructure and Properties of Ductile Iron Castings.

In this work, the results of the examinations of the effect of the mold material and mold technology on the microstructure and properties of the casts parts of ductile cast iron have been presented. Four different self-hardening molding sands based on fresh silica sand from Grudzen Las, with organic binders (no-bake process), were used to prepare molds for tested castings. A novelty is the use of molding sand with a two-component binder: furfuryl resin-polycaprolactone PCL biomaterial. The molds were poured with ductile iron according to standard PN-EN 1563:2018-10. The microstructure of the experimental castings was examined on metallographic cross-sections with PN-EN ISO 945-1:2019-09 standard. Observations were made in the area at the casting/mold boundary and in a zone approximately 10 mm from the surface of the casting with a light microscope. The tensile test at room temperature was conducted according to standard PN-EN ISO 6892-1:2016-09. Circular cross-section test pieces, machined from samples taken from castings, were used. In the present experiment, it was stated that interactions between the mold material of different compositions and liquid cast iron at the stage of casting solidification led to some evolution of casting's microstructure in the superficial layer, such as a pearlite rim observed for acidic mold sand, a ferritic rim for alkaline sand, and graphite spheroids degeneration, especially spectacular for the acidic mold with polycaprolactone (PCL) addition. These microstructural effects may point to the interference of the direct chemical interactions between liquid alloy and the components released from the mold sand, such as sulfur and oxygen. Particularly noteworthy is the observation that the use of molding sand with furfuryl resin with the addition of biodegradable PCL material does not lead to an unfavorable modification of the mechanical properties in the casting. The samples taken from Casting No. 2, made on the acidic molding sand with the participation of biodegradable material, had an average strength of 672 MPa, the highest average strength UTS-among all tested molding sands. However, the elongation after fracture was 48% lower compared to the reference samples from Casting No. 1 from the sand without the addition of PCL.

Brief characteristics of oxidative stability, fatty acids and metal content in selected berry seed extracts obtained by the SFE technique and used as potential source of nutrients.

Berry seeds are rich source of high quality oil containing valuable compounds such as polyunsaturated fatty acids and therefore, have been gaining increasing significance as potential source of nutrients for food, cosmetic or pharmaceutical industry. Supercritical carbon dioxide extraction of seeds was performed, for which oxidative stability analyzes and determinations of fatty acids, selected microelements and toxic metals were carried out. An attempt was made to evaluate unclassified scCO2 oil extracts from berry seeds, taking into account the lack of legislative documents specifying the required contents of metals and biologically active ingredients. The obtained extracts are products with the consistency of liquid oil. The total fatty acid content range from 59% to 98%, with unsaturated fatty acids predominating and very good n-3/n-6 fatty acids ratio. The analyzed samples were taken systematically from one extraction sequence also determining the acid and the peroxide values in subsequent fractions.

Bimetallic coordination polymers via combination of substitution-inert building blocks and labile connectors.

A rational approach to the synthesis of silver-chromium mixed-metal coordination polymers is presented: 3-cyanoacetylacetone (HacacCN) features two potential binding sites. After deprotonation, it has been used as a chelating dionato ligand in the pseudo octahedral complex Cr(acacCN) 3; two polymorphs of this compound have been identified. In its protonated form, HacacCN was employed as a N donor toward Ag(I). Both functionalities may be exploited within the same solid: The chromium complex and silver salts of weakly coordinating anions have been successfully combined to mixed-metal coordination polymers. Cr(acacCN) 3 plays the role of a substitution-inert tecton with predictable bonding geometry which interacts with the conformationally soft silver cations via two or all three of its peripheric nitrile groups. From an equimolar amount of both constituents, six solids featuring a 1:1 ratio between Cr- and Ag-derived building blocks were obtained in good yield; their structures depend on the counteranions and the cocrystallized solvent and correspond either to 2D networks with (6,3) or augmented (4,4) topology or, in one case, adopt a 3D connectivity. In addition, three products with a Cr/Ag = 2:1 stoichiometry have been isolated: they adopt two-dimensional network structures.

Cationic rare-earth metal bis(tetrahydridoborato) complexes: direct synthesis, structure and ring-opening polymerisation activity toward cyclic esters.

Rare-earth metal tris(borohydrides) [Ln(BH4)3(thf)3] (Ln = Y, La, Nd, Sm) are converted with one equivalent of the Brønsted acid [NEt3H]+[BPh4]- in thf into the monocationic bis(borohydride) complexes [Ln(BH4)2(thf)5]+[BPh4]-. They efficiently initiate the ring-opening polymerisation of epsilon-caprolactone.

Lutetium alkyl and hydride complexes in a non-cyclopentadienyl coordination environment.

Lutetium alkyl complexes [Lu(L)(CH(2)SiMe(3))(THF)(n)], which contain a sulfur-linked bis(phenolato) ligand such as 2,2'-thiobis(6-tert-butyl-4-methylphenolate) (L=tbmp, 1) or 1,4-dithiabutanediyl-bis(6-tert-butyl-4-methylphenolate) (L=etbmp, 2), were isolated from the reaction of the lutetium tris(alkyl) complex [Lu(CH(2)SiMe(3))(3)(THF)(2)] with H(2)L. The monomeric structures of these complexes were confirmed by X-ray diffraction studies, showing distorted octahedral geometry around the metal centre. The reaction of [Lu(tbmp)(CH(2)SiMe(3))(THF)(2)] (1) with alcohols ROH (R=iPr, CHPh(2), CPh(3)) results in the formation of the corresponding alkoxide complexes [Lu(tbmp)(OR)(THF)(n)] (4-6). With PhSiH(3) hydride complexes [Lu(L)(mu-H)(THF)(n)](2) (L=tbmp, 7; etbmp, 8) have been prepared in moderate to good yields. They adopt a dimeric form in the solid state as revealed by the X-ray crystal structure of 7. The reactivity of the hydride complexes and their catalytic activity in the ring-opening polymerisation of L-lactide and the hydrosilylation of alkenes are also discussed.