Effect of Hybrid Type and Harvesting Season on Phytochemistry and Antibacterial Activity of Extracted Metabolites from Salix Bark

Hundreds of different fast-growing Salix hybrids have been developed mainly for energy crops. In this paper, we studied water extracts from the bark of 15 willow hybrids and species as potential antimicrobial additives. Treatment of ground bark in water under mild conditions extracted 12-25% of the dry material. Preparative high-performance liquid chromatography is proven here as a fast and highly efficient tool in the small-scale recovery of raffinose from Salix bark crude extracts for structural elucidation. Less than half of the dissolved material was assigned by chromatographic (gas chromatography and liquid chromatography) and spectroscopic (mass spectrometry and nuclear magnetic resonance spectroscopy) techniques for low-molecular-weight compounds, including mono- and oligosaccharides (sucrose, raffinose, and stachyose) and aromatic phytochemicals (triandrin, catechin, salicin, and picein). The composition of the extracts varied greatly depending on the hybrid or species and the harvesting season. This information generated new scientific knowledge on the variation in the content and composition of the extracts between Salix hybrids and harvesting season depending on the desired molecule. The extracts showed high antibacterial activity on Staphylococcus aureus with a minimal inhibitory concentration (MIC) of 0.6-0.8 mg/mL; however, no inhibition was observed against Escherichia coli, Enterococcus faecalis, and Salmonella typhimurium. MIC of triandrin (i.e., 1.25 mg/mL) is reported for the first time. Although antibacterial triandrin and (+)-catechin were present in extracts, clear correlation between the antibacterial effect and the chemical composition was not established, which indicates that antibacterial activity of the extracts mainly originates from some not yet elucidated substances. Aquatic toxicity and mutagenicity assessments showed the safe usage of Salix water extracts as possible antibacterial additives.

Reductive Catalytic Depolymerization of Semi-industrial Wood-Based Lignin

The current work studies the reductive catalytic depolymerization (RCD) of lignin from a novel semi-industrial process. The aim was to obtain aromatic mono-, di-, tri-, and tetramers for further valorization. The substrate and products were characterized by multiple analytical methods, including high pressure size-exclusion chromatography (HPSEC), gas chromatography–mass spectrometry, GC-flame ionization detector (FID), GC-FID/thermal conductivity detector (TCD), and NMR. The RCD was studied by exploring the influence of different parameters, such as lignin solubility, reaction time, hydrogen pressure, reaction temperature, pH, type and loading of the catalyst, as well as type and composition of the organic/aqueous solvent. The results show that an elevated temperature, a redox catalyst, and a hydrogen atmosphere are essential for the depolymerization and stability of the products, while the reaction medium also plays an important role. The highest obtained mono- to tetramers yield was 98% and mono- to dimers yield over 85% in the liquid phase products. The reaction mechanisms influenced the structure of the aliphatic chain in the monomers, but left the phenolic structure along with the methoxy groups largely unaltered. The current work contributes to the development and debottlenecking of the novel and sustainable overall process, which utilizes efficiently all the fractions of wood, in line with the principles of green engineering and chemistry.

Effects of supplementation of sea buckthorn press cake on mycelium growth and polysaccharides of Inonotus obliquus in submerged cultivation

AIMS

Investigation of the influence of cultivation time and sea buckthorn press cake (Hippophaë rhamnoides) dosage on mycelium yield of Inonotus obliquus in submerged cultivation and on the yield, monomer composition, and macromolecular properties of the exopolysaccharides (EPS) from culture media and intracellular polysaccharides (IPS) extracted from mycelia.

METHODS AND RESULTS

Supplementation at 5 g l^-1 combined with cultivation time of 250 h granted highest yield increase in mycelia (by 122%). The supplementation reduced extraction yield and decreased the molecular weight of the main IPS population. The supplementation increased production and molecular weight of EPS. The relative content of arabinose and rhamnose in EPS positively correlated with dosage of the press cake. The press cake supplementation increased the content of galacturonic acid in IPS, but not in EPS.

CONCLUSION

Sea buckthorn press cake is a food industry fibrous side stream with high oil content. It increases the cultivation yield of Inonotus obliquus mycelium and influences the produced polysaccharides.

SIGNIFICANCE AND IMPACT OF THE STUDY

Mycelium is a resource of bioactive polysaccharides, attracting the interest of nutraceutical companies. Sea buckthorn press cake is a promising supplement for increasing mycelium production. The utilization of this agricultural side stream would therefore favour circular economy.

Recovery of Bioactive Compounds from Hazelnuts and Walnuts Shells: Quantitative-Qualitative Analysis and Chromatographic Purification

Hazelnut (HS) and walnut (WS) shells, an abundant by-product of the processing industries of these edible nuts, are traditionally considered as a low-value waste. However, they are a source of valuable compounds with an interesting chemical profile for the chemical and pharmaceutical sectors. In this study, the lipophilic and hydrophilic extracts present in HS and WS were quantified and identified, then the polar fractions were chromatographically separated, and their antioxidant capacity was studied. The experimental work includes the isolation of crude lipophilic and hydrophilic extracts by an accelerated extraction process, chromatographic analysis (gas chromatography-flame ionization (GC-FID), GC-mass spectroscopy (GC-MS), high-performance size-exclusion chromatography (HPSEC), thin-layer chromatography (TLC)), and quantification of the components. In addition, a thorough compositional characterization of the subgroups obtained by flash chromatography and their antioxidant capacity was carried out. The gravimetric concentrations showed different lipophilic/hydrophilic ratios (0.70 for HS and 0.23 for WS), indicating a higher proportion of polar compounds in WS than in HS. Moreover, the lipophilic extracts were principally composed of short-chain fatty acids (stearic, palmitic, and oleic acid), triglycerides, and sterols. The polar fractions were screened by thin-layer chromatography and then separated by flash chromatography, obtaining fractions free of fatty acids and sugar derivatives (97:3 in HS and 95:5 in WS), and mixtures richer in phenolic compounds and flavonoids such as guaiacyl derivatives, quercetin, pinobanksin, and catechin. The most polar fractions presented a higher antioxidant capacity than that of the crude extracts.

Oiling of American white pelicans, common loons, and northern gannets in the winter following the Deepwater Horizon (MC252) oil spill

The Natural Resource Damage Assessment and Restoration Trustees for the Deepwater Horizon oil spill assessed the external oiling of migratory bird species dependent on open water in the Gulf of Mexico following the aforementioned spill. The assessment was designed to evaluate birds that use open water during the winter within 40 km of the Gulf shoreline. We focused on the American white pelican (Pelecanus erythrorhynchos), common loon (Gavia immer), and northern gannet (Morus bassanus). Point counts (pelican, loon) or strip transects (gannet) were used and each target species was assessed for oiling (unoiled, trace, light, moderate, or heavy amounts) and photographed. Due to distance at sighting and/or poor visibility, not all visible birds were assessed. The percentage of birds oiled varied by species, with the common loon being the highest (23.6%), followed by American white pelican (16.9%), and northern gannet (6.9%). Most of the American white pelicans and common loons had trace (83% and 72%, respectively) or light levels (11% and 24%, respectively) of oiling. The northern gannet had just trace levels of oiling. Some pelicans (6%) and loons (4%) had moderate amounts of oiling. Based on expert derived-mortality estimates and our estimates of oil exposure, we used Monte Carlo simulations to predict expected decreases of 2.5%, 4%, and 11% in the observed population for the northern gannet, American white pelican, and common loon, respectively. While these values are underestimates of the true values given the long time lag (10-12 months) between the oil spill and the assessment, these data represent some of the few estimates of exposure for these species and describe minimum risk estimates to these species.

Synthesis of menthol from citronellal over supported Ru- and Pt-catalysts in continuous flow

One-pot menthol synthesis in a trickle bed reactor was investigated using Ru/H-beta-300 extrudates without any binder and Pt- and Ru/H-beta-25 extrudates containing 30 wt% bentonite binder using different methods of metal loading on the extrudates.

Hydrodeoxygenation of Isoeugenol over Alumina-Supported Ir, Pt, and Re Catalysts

Hydrodeoxygenation (HDO) of isoeugenol (IE) was investigated using bimetallic iridium-rhenium and platinum-rhenium catalysts supported on alumina in the temperature and pressure ranges of 200-250 °C and 17-40 bar in nonpolar dodecane as a solvent. The main parameters were catalyst type, hydrogen pressure, and initial concentration. Nearly quantitative yield of the desired product, propylcyclohexane (PCH), at complete conversion in 240 min was obtained with Ir-Re/Al₂O₃ prepared by the deposition-precipitation method using 0.1 mol/L IE initial concentration. High iridium dispersion together with a modification effect of rhenium provided in situ formation of the IrRe active component with reproducible catalytic activity for selective HDO of IE to PCH. The reaction rate was shown to increase with the increasing initial IE concentration promoting also HDO and giving a higher liquid phase mass balance. Increasing hydrogen pressure benefits the PCH yield.

Enzymatic hydrolysis of biomimetic bacterial cellulose-hemicellulose composites

The production of biofuels and other chemicals from lignocellulosic biomass is limited by the inefficiency of enzymatic hydrolysis. Here a biomimetic composite material consisting of bacterial cellulose and wood-based hemicelluloses was used to study the effects of hemicelluloses on the enzymatic hydrolysis with a commercial cellulase mixture. Bacterial cellulose synthesized in the presence of hemicelluloses, especially xylan, was found to be more susceptible to enzymatic hydrolysis than hemicellulose-free bacterial cellulose. The reason for the easier hydrolysis could be related to the nanoscale structure of the substrate, particularly the packing of cellulose microfibrils into ribbons or bundles. In addition, small-angle X-ray scattering was used to show that the average nanoscale morphology of bacterial cellulose remained unchanged during the enzymatic hydrolysis. The reported easier enzymatic hydrolysis of bacterial cellulose produced in the presence of wood-based xylan offers new insights to overcome biomass recalcitrance through genetic engineering.

Novel biorenewable composite of wood polysaccharide and polylactic acid for three dimensional printing

Hemicelluloses, the second most abundant polysaccharide right after cellulose, are in practice still treated as a side-stream in biomass processing industries. In the present study, we report an approach to use a wood-derived and side-stream biopolymer, spruce wood hemicellulose (galactoglucomannan, GGM) to partially replace the synthetic PLA as feedstock material in 3D printing. A solvent blending approach was developed to ensure the even distribution of the formed binary biocomposites. The blends of hemicellulose and PLA with varied ratio up to 25% of hemicellulose were extruded into filaments by hot melt extrusion. 3D scaffold prototypes were successfully printed from the composite filaments by fused deposition modeling 3D printing. Combining with 3D printing technique, the biocompatible and biodegradable feature of spruce wood hemicellulose into the composite scaffolds would potentially boost this new composite material in various biomedical applications such as tissue engineering and drug-eluting scaffolds.

Comparative study of sulfur-free nickel and palladium catalysts in hydrodeoxygenation of different fatty acid feedstocks for production of biofuels

Catalytic hydrodeoxygenation (HDO) of fatty acids has been investigated using different feedstocks for renewable diesel production.

Active targeting of mesoporous silica drug carriers enhances γ-secretase inhibitor efficacy in an in vivo model for breast cancer

Aim: In this article, we use an alternative cancer model for the evaluation of nanotherapy, and assess the impact of surface functionalization and active targeting of mesoporous silica nanoparticles (MSNPs) on therapeutic efficacy in vivo. Materials & methods: We used the chorioallantoic membrane xenograft assay to investigate the biodistribution and therapeutic efficacy of folate versus polyethyleneimine-functionalized γ-secretase inhibitor-loaded MSNPs in breast and prostate tumor models. Results: γ-secretase inhibitor-loaded MSNPs inhibited tumor growth in breast and prostate cancer xenografts. Folate conjugation improved the therapeutic outcome in folic acid receptor-positive breast cancer, but not in prostate cancer lacking the receptor. Conclusion: The results demonstrate that therapeutic efficacy is linked to cellular uptake of MSNPs as opposed to tumor accumulation, and show that MSNP-based delivery of γ-secretase inhibitors is therapeutically effective in both breast and prostate cancer. In this article, we present a model system for a medium-to-high throughput, cost-effective, quantitative evaluation of nanoparticulate drug carriers.

Original submitted 12 November 2012; Revised submitted 8 February 2013

The Breakthrough Generations Study: design of a long-term UK cohort study to investigate breast cancer aetiology

BACKGROUND

The rationale, design, recruitment and follow-up methods are described for the Breakthrough Generations Study, a UK cohort study started in 2003, targeted at investigation of breast cancer aetiology.

METHODS

Cohort members have been recruited by a participant referral method intended to assemble economically a large general population cohort from whom detailed questionnaire information and blood samples can be obtained repeatedly over decades, with high completeness of follow-up and inclusion of large numbers of related individuals. 'First-generation' recruits were women contacted directly, or who volunteered directly, to join the study. They nominated female friends and family, whom we contacted, and those who joined ('second generation') nominated others, reiterated for up to 28 generations.

RESULTS

The method has successfully been used during 2003-2011 to recruit 112,049 motivated participants with a broad geographic and socioeconomic distribution, aged 16-102 years, who have completed detailed questionnaires; 92% of the participants gave blood samples at recruitment. When eligible, 2½ years after recruitment, >98% completed the first follow-up questionnaire. Thirty percent are first-degree relatives of other study members.

CONCLUSION

The 'generational' recruitment method has enabled recruitment of a large cohort who appear to have the commitment to enable long-term continuing data and sample collection, to investigate the effects of changing endogenous and exogenous factors on cancer risk.

Scots pine (Pinus sylvestris) bark composition and degradation by fungi: potential substrate for bioremediation

The composition of Scots pine bark, its degradation, and the production of hydrolytic and ligninolytic enzymes were evaluated during 90 days of incubation with Phanerochaete velutina and Stropharia rugosoannulata. The aim was to evaluate if pine bark can be a suitable fungal substrate for bioremediation applications. The original pine bark contained 45% lignin, 25% cellulose, and 15% hemicellulose. Resin acids were the most predominant lipophilic extractives, followed by sitosterol and unsaturated fatty acids, such as linoleic and oleic acids. Both fungi degraded all main components of bark, specially cellulose (79% loss by P. velutina). During cultivation on pine bark, fungi also degraded sitosterol, produced malic acid, and oxidated unsaturated fatty acids. The most predominant enzymes produced by both fungi were cellulase and manganese peroxidase. The results indicate that Scots pine bark supports enzyme production and provides nutrients to fungi, thus pine bark may be suitable fungal substrate for bioremediation.

Kinetics of acid hydrolysis of water-soluble spruce O-acetyl galactoglucomannans

Water-soluble O-acetyl galactoglucomannan (GGM) is a softwood-derived polysaccharide, which can be extracted on an industrial scale from wood or mechanical pulping waters and now is available in kilogram scale for research and development of value-added products. To develop applications of GGM, information is needed on its stability in acidic conditions. The kinetics of acid hydrolysis of GGM was studied at temperatures up to 90 degrees C in the pH range of 1-3. Molar mass and molar mass distribution were determined using size exclusion chromatography with multiangle laser light scattering and refractive index detection. The molar mass of GGM decreased considerably with treatment time at temperatures above 70 degrees C and pH below 2. The molar mass distribution broadened with hydrolysis time. A first-order kinetic model was found to match the acid hydrolysis. The reaction rate constants at various pH values and temperatures were calculated on the basis of the first-order kinetic model. Furthermore, the activation energy, E, was obtained from the Arrhenius plot. The activation energy E was 150 kJ mol (-1) for acid hydrolysis of spruce GGM. The apparent rate constant during acid hydrolysis increased by a factor of 10 with a decrease in pH by 1 unit, regardless of temperature. In addition, gas chromatography and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry were applied to study the released GGM monomers and oligomers.

Evolutionary implications of permanent odd polyploidy in the stable sexual, pentaploid of Rosa canina L

In Rosa canina (2n = 5x = 35), the pollen and ovular parents contribute, respectively, seven and 28 chromosomes to the zygote. At meiosis I, 14 chromosomes form seven bivalents and 21 chromosomes remain as univalents. Fluorescent in situ hybridization to mitotic and pollen mother cells (PMC) of R. canina showed that 10 chromosomes (two per genome) carry ribosomal DNA (rDNA) loci. Five chromosomes carry terminal 18S-5.8S-26S rDNA loci; three of these also carry paracentric 5S rDNA loci and were designated as marker chromosomes 1. Five chromosomes carry only 5S rDNA loci and three of these were designated as marker chromosomes 2. The remaining four of the 10 chromosomes with rDNA loci were individually identifiable by the type and relative sizes of their rDNA loci and were numbered separately. At PMC meiosis, two marker chromosomes 1 and two marker chromosomes 2 formed bivalents, whereas the others were unpaired. In a gynogenetic haploid of R. canina (n = 4x = 28), obtained after pollination with gamma-irradiated pollen, chromosomes at meiosis I in PMC remained predominantly unpaired. The data indicate only one pair of truly homologous genomes in R. canina. The 21 unpaired chromosomes probably remain as univalents through multiple generations and do not recombine. The long-term evolutionary consequence for the univalents is likely to be genetic degradation through accumulated mutational change as in the mammalian Y chromosome and chromosomes of asexual species. But there is no indication that univalents carry degenerate 5S rDNA families. This may point to a recent evolution of the R. canina meiotic system.

Effects of wood-related sterols on the offspring of the viviparous blenny, Zoarces viviparus L

The parent generation of the viviparous blenny, Zoarces viviparus L., were exposed to phytosterols (a) from oogenesis to parturition and (b) from breeding to parturition. The experiments were performed under laboratory conditions in a test unit supplied with continuous renewal of brackish water. After parturition the offspring were further reared either in clean or in phytosterol-contaminated brackish water. The objective was to study the significance of preexposure of the parent on the effects of phytosterols on the offspring in comparison with effects occurring directly on previously unexposed offspring. The phytosterol concentrations used were (a) 0, 10, 20, and 30 microg/L and (b) 0, 10, and 20 microg/L. Offspring exposed in (a) was further reared in clean water and in (b) offspring from parents exposed to 10 microg/L was either exposed further in the same concentration or left in clean water. Offspring from parents exposed to 20 microg/L was further exposed in the same concentration. Finally one group from unexposed parents was exposed to 10 microg/L after birth. The offspring was studied for 6 months after birth. The results showed that blenny offspring are affected by phytosterols at exposure through the parental generation. The results imply that phyto- sterols affect embryological development of the larvae before hatching as well as the levels of circulating hormones of the parent fish. The larvae contained higher levels of phytosterols as did controls and the bile of exposed female fish contained lower levels of phytosterols implying a link between the higher levels in larvae and lower excretion of the females. The growth of the larvae at 10 microg/L was stimulated regardless of whether the larvae were further exposed, indicating that newborn larvae carried within the female are sensitive to exposure to phytosterols.

Effects of wood-related sterols on the reproduction, egg survival, and offspring of brown trout (Salmo trutta lacustris L.)

Maturing lake trout (Salmo trutta lacustris) of both sexes were exposed to 10 and 20 microg/liter phytosterols, mainly ss-sitosterol, for 4.5 months prior to spawning. Eggs from preexposed females were artificially fertilized with milt from preexposed males in clean water, whereupon the eggs were incubated in clean water until hatching. Yolk sac fry were followed until swim-up, and mortality as well as deformities was recorded. The physiological status of the parent fish was documented, as was the occurrence of phytosterols in bile liquid and gonads. In addition, eggs from preexposed females were fertilized with milt from unexposed males to evaluate the existence of possible sex-linked differences. The results indicate a markedly increased dose-dependent egg mortality, smaller egg size, and lower mean weight of the the yolk sac stage larvae. There was a higher prevalence of deformed or otherwise diseased larvae, especially at the higher dose, but also in the groups where unexposed males were used for fertilization, indicating a female-linked effect mechanism. A causal link between effects on eggs and brood was obtained through a dose-dependent increase in phytosterols in the roe. Several physiological parameters (higher plasma estradiol, higher 7-ethoxyresorufin O-deethylase activity) implied slower maturation of the exposed female fish, whereas indications of accelerated maturation were obtained for the male fish from the same groups. The results indicate that naturally occurring wood-derived compounds in pulp mill effluents may be responsible for reproductive impacts previously observed in fish both in the laboratory and in the receiving waters of pulp mill effluents. The results also suggest that more attention should be paid to process streams emanating from the unbleached part of the mill.

Experimental field exposure of brown trout to river water receiving effluent from an integrated newsprint mill

Effects of effluents from mechanical pulp production on brown trout were studied for 8 weeks at environmentally relevant concentrations. The exposure took place in laboratory-based pools upstream and downstream of the effluent discharge point of an integrated newsprint mill using ground wood/thermomechanical pulp. The mill had no secondary treatment of the wastewater. The pools were supplied with water pumped directly from the river. To determine the relevance of this approach, wild fish were also caught at the respective sites upstream and downstream from the mill. Sublethal effects were assessed using physiological and biochemical parameters including liver histology, hematology, serum biochemistry, and hepatic enzyme assays. Exposure was verified by analyzing water samples, fish bile, and tissues for resin acid concentrations. The downstream experimental fish and captured feral fish displayed responses and changes in physiological parameters similar to those previously observed in laboratory experiments with untreated effluents. The most obvious effects were liver damage and growth inhibition.