Tung oil as an effective modifier for sulfur polymer cement and its performance in galvanic waste encapsulation.

The data on the performance of sulfur polymer cement crosslinked with tung oil polymerization modifier are presented. Specimens of sulfur polymer cement (SPC) were prepared with different doses of tung oil in amounts of up to 8.85% of the sulfur mass. The obtained SPCs were used as binders to encapsulate two galvanic wastes differing in their toxic metal composition: waste I and waste II with loadings of approximately 25 and 50% of the composites' mass, respectively. For comparative purposes, appropriate samples of the SPCs and their composites with galvanic wastes were obtained using very similar doses of dicyclopentadiene sulfur modifier. Waste II was also encapsulated using SPC, in which a mixture of tung oil and dicyclopentadiene in a 1:1 weight ratio was used as the modifier. Crosslinking of the tung oil to the SPC matrix was assessed by FT-IR. The obtained SPCs and their composites with galvanic wastes were characterized by SEM and tested for water sorption capacity, compressive strength and metal leaching toxicity using TCLP and EN standards. The effectiveness of the tung oil binding to the SPC network was evidenced by the complete disappearance of methine C-H stretching vibrations at 3010 cm-1 and the double bond -C=C- wagging vibrations at 990 cm-1 in the FT-IR spectrum after processing with sulfur. SEM observations revealed that all the specimens prepared with dicyclopentadiene had a glassy-like fracture surface and also showed fewer cavities and defects in cements and composites when compared to their counterparts prepared with tung oil. The water sorption capacities of all the specimens were below 1%, where the values of those prepared with the tung oil were two to three fold higher than the values of their counterparts prepared with dicyclopentadiene. The pH of the TCLP leachates was in the range of 2.75-2.98, and a decreasing trend in the pH value was found with an increasing modifier dose. The TCLP leachate pH from the waste I monoliths with dicyclopentadiene were generally lower by 0.1-0.35 when compared to the corresponding monoliths with tung oil. The toxic metals immobilization order revealed from the TCLP test (leachate pH around 2.85) is Cd > Sr ≥ Zn > Cu > Ni > Cr > Pb, while the resulting order from the EN test, due to a higher leachate pH of about 5.9, follows Cd > Pb > Zn > Cu ≥ Ni > Sr > Cr. An increased tung oil dose from 2 to 8.85% enhanced the SPC compressive strength by three to four fold, while the same increase of the dicyclopentadiene dose led to an increase of this parameter for less than two fold. The addition of galvanic wastes to the SPCs resulted in a further increase in compressive strength for the corresponding SPC samples.

The polyphenolic-polysaccharide complex of Agrimonia eupatoria L. as an indirect thrombin inhibitor - isolation and chemical characterization.

The polyphenolic-polysaccharide complex was isolated from the dried aerial parts of the medicinal plant Agrimonia eupatoria L. using a multi-step process involving the degreasing of the plant material by extraction with organic solvents, followed by extraction with hot alkali, neutralization, further separation with organic solvents and dialysis. The complex was homogeneous with a molecular weight of about 55 × 103 g/mol and consisted mainly of carbohydrates and polyphenols matrix, composed of lignin-related units, with the dominance of dimethoxyphenyl structures. The carbohydrate moiety consists mostly of arabinogalactan associated with highly esterified rhamnogalacturonan. In vitro anticoagulant studies revealed the ability of the A. eupatoria complex to inhibit plasma clot formation, mainly in the intrinsic pathway of the blood coagulation cascade. Further studies on the mechanisms of this anticoagulant activity revealed that the isolate was primarily an indirect inhibitor of thrombin, mediated by antithrombin or by heparin cofactor II. Such mechanism of action is characteristic for highly sulfated glycosaminoglycans.

Polyphenolic glycoconjugates from medical plants of Rosaceae/Asteraceae family protect human lymphocytes against γ-radiation-induced damage.

Radioprotective effects of the water-soluble polyphenolic glycoconjugates, isolated from flowers of Sanguisorba officinalis L.(SO) and Erigeron canadensis L.(EC), and from leaves of Fragaria vesca L. (FV) and Rubus plicatus Whe. Et N. E. (RP), against γ-radiation-induced toxicity in human peripheral blood lymphocytes were investigated. Cell treatment with glycoconjugates (1, 5 and 25µg/mL) prior exposure to 10/15Gy radiation resulted in concentration-dependent reduction of DNA damage including oxidative DNA lesions (comet assay), substantial inhibition of lipid peroxidation (TBARS) and restoration of superoxide dismutase and S-glutathione transferase activities. Glycoconjugates isolated from SO and EC ensured better protection versus these from RP and FV, with the SO product potential comparable to that of the reference quercetin. Strong antioxidant/radioprotective activity of the SO and EC glycoconjugates could be attributed to high abundance of syringol-type and ferulic acid units in their matrices, respectively. Moreover, polyphenolic glycoconjugates (25µg/mL), including RP and FV products, significantly decreased DNA damage when applied post-radiation suggesting their modulating effects on DNA repair pathways. Preliminary data on the glycoconjugate phenolic structural units, based on GLC/MS of the products of pyrolysis and in situ methylation, in relation to application of plant products as potential radioprotectors is promising and deserves further investigation.

Thiosteranes in samples impacted by fecal materials and their potential use as marker of sewage input.

Sewage impacted soil, sludge and water samples were studied to understand the occurrence and formation of thiosteranes and to determine the relevance of these compounds as tracers for sewage input into the environment. Soils were collected from wastewater irrigation fields (Wroclaw, Poland), water from the Nexapa River Basin (Mexico), which also received wastewater and wastewater treatment plant(WWTP) effluent, and water and sludge from the Norman WWTP (USA) at different treatment stages. Thiosteranes represented a high proportion of the steroid fraction in the Wroclaw irrigation field and the Nexapa River Basin samples. Small amounts of thiosteranes were found in anaerobically digested sludge from the Norman WWTP. A good correlation between coprostanone and thiosterane concentrations suggests thiosteranes were produced by stanone sulphurization under anoxic conditions. Thiosterane stability under anoxic and suboxic conditions indicates their potential use as tracers for environmental input of sewage products or land application of sewage sludge.

The influence of conjugates isolated from Matricaria chamomilla L. on platelets activity and cytotoxicity.

Cardiovascular diseases (CVD) remain the principal cause of death in both advanced and developing countries of the world. Blood platelets are involved in the pathogenesis of atherosclerosis and thrombosis. Platelet adhesion and aggregation are critical events that occur in unstable coronary syndromes. The current research is focused on the role of polysaccharide-polyphenolic conjugates isolated from chamomile (Matricaria chamomilla L.) at concentrations of 10, 25, 50 and 100 µg/mL on blood platelets (obtained from healthy donors and from patients received combined anti-platelet therapy complex with clopidogrel and acetylsalicylic acid) aggregation and experimentally induced cell toxicity. The treatment of PRP obtained from healthy donors with polyphenolic-polysaccharide conjugates from M. chamomilla (L.) (MC) resulted in a dose-dependent, decrease of platelet aggregation induced by multiple agonists (ADP, collagen and arachidonic acid). In this study we also observed that the MC reduced platelet aggregation in PRP obtained from patients with cardiovascular disorders. The result of testing the MC on human blood platelets, mouse fibroblast cultures L929 and human lung cells A549 did not show any cytotoxicity effects. Compounds obtained from M. chamomilla L. are potential composite to the development of a new anti-platelet agent, which could be an alternative to the currently used anti-platelet drugs.

Sewage sludge stabilisation with calcium hydroxide: effect on physicochemical properties and molecular composition.

Raw primary sewage sludge (Wastewater Treatment Plant of Krotoszyn, SW Poland) and its mixtures with 3%d, 6%d, 9%d, 12%d and 24%d of calcium hydroxide were stabilised for 1 and 35 days. Changes of the sludge physicochemical properties and molecular composition, caused by alkaline agent in course of stabilisation process, are recognised. A basic physicochemical data on the sludge cake and filtrate after 1 and 35 days of stabilisation process are given. Soxhlet extracts from the sludge cakes stabilised for 35 days as well pyrolysis and pyrolysis in situ methylation (using tetramethylammonium hydroxide-TMAH) products of respective pre-extracted cake residues were analysed by gas chromatography-mass spectrometry (GC-MS). Increase of calcium hydroxide concentration in the sludge mixture causes enhanced ammonia release, preferential hydrolyses of fats and proteins from the sludge macromolecular network and transformation of free fatty acids contained in the sludge lipids, as well as these released hydrolytically, to their calcium salts. The sewage sludge stabilisation with calcium hydroxide has no effect on homological assemblage and content of unbound stanol and sterol compounds in the sludge lipids and these bound into macromolecular network. Biogenic n-alkanes and anthropogenic linear alkylbenzenes were detected as minor components in the lipids and pyrolytic products from the pre-extracted cake residue, respectively. The alkaline agent used for the sludge stabilisation accelerates equilibration of the process and reduces content of pathogenic microorganisms.

Organic matter transformation in the environment investigated by quantitative electron paramagnetic resonance (EPR) spectroscopy: studies on lignins.

The lignins separated from angiosperm and gymnosperm trees, peat and xylitic brown coal were investigated by quantitative EPR. Observed free radicals in lignins are sensitive to alkaline environment. Gaseous ammonia interacting with solid lignins in resonance cavity shifts quinone-hydroquinone equilibria towards formation of semiquinone anions. Complexation of copper(II) by lignins causes drastic decrease of the semiquinones in the matrices. Formation of lignin-Pb(II) complexes yielded radicals characterised by unusually low g-value (1.9999-2.0003). Monomeric structural units of the investigated lignins were recognised by pyrolysis with in situ methylation by tetramethylammonium hydroxide. Although for the natural lignins the mixture of normal semiquinone signals at g about 2.0034 and signals at g 1.9999 were observed, some monomeric components of lignins (e.g., caffeic acid, pyrogallol) gave pure lines at g = 1.9999. The bacterial oxidative biodegradation of lignin monomeric components and their Pb(II) complexes resulted in increase of the radical signals.

Quantitative EPR study on free radicals in the natural polyphenols interacting with metal ions and other environmental pollutants.

Quantitative electron paramagnetic resonance (EPR) method was applied to characterise radicals stabilised in polyphenolic matrices of various biogenic materials: lichens, mosses, composts, soils, peats, brown coals and sewage sludge sediments. The investigations were carried out on raw materials and extracted fractions of humic acids (HA). General trends of g value and spin concentration changes were found. These parameters in lichens strongly depend on lichen species and air pollution. Determination of the g value and semiquinone spin concentration allows to assess degree of transformation of organic matter in compost, soil, peat and lignite. Application of gaseous ammonia as a base penetrating the organic matrices extends the possibilities and usefulness of the method. Interaction of metal ions with humic materials is illustrated by interaction of VO2+ ion with peat and lignite HA as well as demineralised (raw and carbonised) brown coal. Our investigations demonstrate that quantitative EPR is a rapid and effective monitoring method to study the influence of various environmental factors on substances containing polyphenolic matrices.