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Hybrid aspens have long attracted scientific interest, but the research on their use as feedstocks for chemical applications are still very limited. The bark biomass of the poplar species contains many valuable extractives that can be utilized as value-added products. This paper examines the applicability of hybrid aspen (Populus tremula L. × P. tremuloides Michx.) bark extract as a precursor of rigid carbon foam and activated carbon. To explore this, the study considers 1) the basic chemical composition of the bark in terms of added value potential, 2) the basic chemical composition of the bark extract and the effect of its pretreatment on the extract composition, 3) the production of rigid carbon foam, and 4) the chemical activation of carbon foam with different impregnating agents. The study determines that the bark extract of the hybrid aspen can be used as a precursor for rigid carbon foam and further processed into an activated carbon product. Therefore, the bark extract of Populus tremula L. × P. tremuloides Michx. can be assessed as a potential value-added product that increases the use value of the hybrid aspen biomass. peerReviewed

Appropriate waste and resource management are essential for a sustainable circular economy with reduced environmental impact. With critical resources, e-waste may serve as indirect raw material. For example, with NdFeB permanent magnets, Neodymium (Nd) and the co-present Dysprosium (Dy) are critical rare earth elements (REEs). However, there exists no economically viable technology for recycling them from electronic waste (e-waste). Here, a method is presented based on cloud point extraction (CPE). The work involves basic complexation chemistry in a cloud medium with pure REE salts, as well as, with real NdFeB-magnets (nearly 28% REE content by weight) from an old hard disk drive (5.2 g magnet in a 375 g HDD). High extraction efficiency (>95%) was achieved for each REE targeted (Nd, Dy, Praseodymium (Pr)). With the magnet waste, the cloud phase did hardly contain any Nickel (Ni), Cobalt (Co), or Boron (B), but some Aluminium (Al) and Iron (Fe). Dynamic light scattering results indicated aggregation of ligand-surfactant micelles with the cloud phase. The preconcentrated products can be used for new Nd magnet manufacturing or further enriched using established transition metal removal techniques. Reuse of solvent, low chemical inventory demand, and using non-inflammable, non-volatile organic extractants promise safe large-scale operation, low process costs, and less environmental impact than using hydrometallurgical methods used with urban or primary mining., Journal of molecular liquids, 382, ISSN:0167-7322, ISSN:1873-3166

Fast pyrolysis bio-oils (FPBOs) originating from forest residues contain extractive-derived substances, which may form a separate, sticky layer with char particles on the surface of these bio-oils. In this study, first, the removal of extractive-derived substances from the bio-oil top phase was studied by common solvents with different polarities. In this case, the results indicated that when aimed at the maximum yield of single-phase fuel oil and thus the maximum amount of extractives removed, the use of n-heptane or n-hexane seems to be of benefit for this purpose. For safety reasons, the use of n-heptane was recommended. Second, an analysis practice (extraction time and the way of mixing) was optimized. In order to reduce the extraction time and enhance the extraction yield, it was important to break the oil surface in extraction. Third, based on the characterization results of the n-heptane extract by gas chromatography and ultraviolet spectroscopy, the detected compounds were classified as fatty acids, resin acids, esterified fatty acids, terpenoids, and steroids, and their total content (27 wt %) was lower than that of lignin-derived compounds (70 wt %). The extraction of the FPBO top phase with n-heptane followed by this analysis practice was a useful way to estimate the content and composition of lipophilic extractives. peerReviewed

The effects of commercial enzymes (pectinases, cellulases, beta-1-3-glucanases, and pectin lyases) on the recovery of anthocyanins and polyphenols from blackcurrant press cake were studied considering two solid:solvent ratios (1:10 and 1:4 w/v). β-glucanase enabled the recovery of the highest total phenolic content – 1142 mg/100 g, and the extraction of anthocyanins was similar using all enzymes (∼400 mg/100 g). The use of cellulases and pectinases enhanced the extraction of antioxidants (DPPH − 1080 mg/100 g; CUPRAC – 3697 mg/100 g). The freeze-dried extracts presented antioxidant potential (CUPRAC, DPPH), which was associated with their biological effects in different systems: antiviral activity against both non-enveloped viruses (enterovirus coxsackievirus A-9) and enveloped coronaviruses (HCoV-OC43), and cytotoxicity towards cancer cells (A549 and HCT8). No cytotoxic effects on normal human lung fibroblast (IMR90) were observed, and no anti-inflammatory activity was detected in lipopolysaccharides-treated murine immortalised microglial cells. peerReviewed

α-Aminophosphonates, -phosphinates, and -phosphine oxides are a group of organophosphorus compounds that were investigated as extraction agents for rare earth (RE) metals and actinoids for the first time in the 1960s. However, more systematic investigations of their extraction properties towards REs and actinoids were not started until the 2010s. Indeed, recent studies have shown that these α-amino-functionalized compounds can outperform the commercial organophosphorus extraction agents in RE separations. They have also proven to be very efficient extraction and precipitation agents for recovering Th and U from RE concentrates. These actinoids coexist with REs in some of the commercially important RE-containing minerals. The efficient separation and purification of REs is becoming more and more important every year as these elements have a pivotal role in many existing technologies. If one also considers the facile synthesis of α-amino-functionalized organophosphorus extractants and precipitation agents, it is expected that they will be increasingly utilized in the extraction chemistry of REs and actinoids in the future. This review collates α-aminophosphonates, -phosphinates, and -phosphine oxides that have been utilized in the separation chemistry of REs and actinoids, including their most relevant synthetic routes and molecular properties. Their extraction and precipitation properties towards REs and actinoids are also discussed. peerReviewed

Funding Information: This work was supported by Business Finland corona-co-creation funding for the project Antiviral Fibers?pilot with extracts from Finnish forests (grant: 40699/31/2020). This study was also funded by the Natural Resources Institute Finland?s strategic research funding to the projects ?More, faster, higher quality: potential of short-rotation aspen and willow biomass for novel products in bioeconomy? (AspenWill) and ?Added value potential of new and under-utilized fibre sources in Finnish value networks of green bioeconomy: prefeasibility, prototyping, and market acceptance? (VALUEPOT). In addition, Academy of Finland has supported this study via the project ?Antivirals from Forest Biomasses: Structure, Function, and Applicability? (grant: 342250). Work was also funded by Jane and Aatos Erkko Foundation: Novel probes for discovering antivirals. Publisher Copyright: Copyright © 2021 Tienaho, Reshamwala, Sarjala, Kilpeläinen, Liimatainen, Dou, Viherä-Aarnio, Linnakoski, Marjomäki and Jyske. Earlier studies have shown that the bark of Salix L. species (Salicaceae family) is rich in extractives, such as diverse bioactive phenolic compounds. However, we lack knowledge on the bioactive properties of the bark of willow species and clones adapted to the harsh climate conditions of the cool temperate zone. Therefore, the present study aimed to obtain information on the functional profiles of northern willow clones for the use of value-added bioactive solutions. Of the 16 willow clones studied here, 12 were examples of widely distributed native Finnish willow species, including dark-leaved willow (S. myrsinifolia Salisb.) and tea-leaved willow (S. phylicifolia L.) (3 + 4 clones, respectively) and their natural and artificial hybrids (3 + 2 clones, respectively). The four remaining clones were commercial willow varieties from the Swedish willow breeding program. Hot water extraction of bark under mild conditions was carried out. Bioactivity assays were used to screen antiviral, antibacterial, antifungal,yeasticidal, and antioxidant activities, as well as the total phenolic content of the extracts. Additionally, we introduce a fast and less labor-intensive steam-debarking method for Salix spp. feedstocks. Clonal variation was observed in the antioxidant properties of the bark extracts of the 16 Salix spp. clones. High antiviral activity against a non-enveloped enterovirus, coxsackievirus A9, was found, with no marked differences in efficacy between the native clones. All the clones also showed antibacterial activity against Staphylococcus aureus and Escherichia coli, whereas no antifungal (Aspergillus brasiliensis) or yeasticidal (Candida albicans) efficacy was detected. When grouping the clone extract results into Salix myrsinifolia, Salix phylicifolia, native hybrid, artificial hybrid, and commercial clones, there was a significant difference in the activities between S. phylicifolia clone extracts and commercial clone extracts in the favor of S. phylicifolia in the antibacterial and antioxidant tests. In some antioxidant tests, S. phylicifolia clone extracts were also significantly more active than artificial clone extracts. Additionally, S. myrsinifolia clone extracts showed significantly higher activities in some antioxidant tests than commercial clone extracts and artificial clone extracts. Nevertheless, the bark extracts of native Finnish willow clones showed high bioactivity. The obtained knowledge paves the way towards developing high value-added biochemicals and other functional solutions based on willow biorefinery approaches.

The accurate characterization of silver nanoparticles (Ag NPs) in environmental samples is crucial for understanding the potential impact of these materials on the environment and human health. Single-particle inductively coupled plasma mass spectrometry (spICP-MS) is one of the few techniques available for quantifying NPs at environmentally relevant concentrations. However, the spICP-MS detection of Ag NPs can be interfered with coexisting dissolved analyte causing high background signals, which mask NP signals leading to a significant bias in NP characterization. In this paper, a simple sample pre-treatment procedure for efficient removal of dissolved silver in natural waters is proposed using solid phase extraction (SPE) materials, allowing more accurate characterization of NPs in environmental water matrices. The applicability of eight commercially available SPE materials was evaluated based on their effects on sample Ag NP properties and dissolved silver extraction efficiency in environmental waters, which were shown to depend on sample matrix. The SPE materials found most efficient in dissolved silver extraction were further studied for improving the characterization of 30 nm Ag NPs in colorless and dark-colored waters. Whereas dissolved silver concentrations of ≤1 μg kg−1 were shown to lead to a significant bias in NP characterization (up to +58% increase in NP size and − 90% decrease in particle concentration), pre-treatment of the samples with SPE materials ‘SiliaMetS Thiol’ and ‘Purolite C115HMR’ minimized the effect of dissolved silver interference. As a result, highly more accurate NP sizing (28 ± 2 nm) and relatively stable particle concentration was obtained for 30 nm Ag NPs in environmental waters. peerReviewed

Aqueous extracts from blackcurrant press cake (BC), Norway spruce bark (NS), Scots pine bark (SP), and sea buckthorn leaves (SB) were obtained using maceration and pressurized hot water and tested for their bioactivities. Maceration provided the extraction of higher dry matter contents, including total phenolics (TPC), anthocyanins, and condensed tannins, which also impacted higher antioxidant activity. NS and SB extracts presented the highest mean values of TPC and antioxidant activity. Individually, NS extract presented high contents of proanthocyanidins, resveratrol, and some phenolic acids. In contrast, SB contained a high concentration of ellagitannins, ellagic acid, and quercetin, explaining the antioxidant activity and antibacterial effects. SP and BC extracts had the lowest TPC and antioxidant activity. However, BC had strong antiviral efficacy, whereas SP can be considered a potential ingredient to inhibit α-amylase. Except for BC, the other extracts decreased reactive oxygen species (ROS) generation in HCT8 and A549 cells. Extracts did not inhibit the production of TNF-alpha in lipopolysaccharide-stimulated THP-1 macrophages but inhibited the ROS generation during the THP-1 cell respiratory burst. The recovery of antioxidant compounds from these by-products is incentivized for high value-added applications. peerReviewed

Fresh bark from spruce Picea abies was milled and extracted with hot water. The extracts were purified in a number of steps in order to get tannin-extracts pure enough to prepare tannin-based carbon foams. The chemical composition of the extracts were analyzed. The foams were maturated and thermally treated to obtain desired properties, such as specific surface area, porosity, and compressive strength. It was possible to produce carbon foams even if they contained carbohydrate impurities. Differences in the properties of the carbon foams such as compressive strength, specific surface areas, and pore size distributions might be related to the compositions of the extracts. The foams were finally activated chemically and physically and were tested in adsorption of methylene blue. Results from the adsorption tests showed that adsorption was highly related to the total pore volume and the amount of mesopores created inside the foam structure during the thermal treatment.

Toxicity of silver nanoparticles (AgNPs) to benthic organisms is a major concern. The use of AgNPs in industry and consumer products leads to increasing release of AgNPs into the aquatic environment-sediments being the major sink. Effects of sediment pH on the toxicity of AgNPs to benthic oligochaeta Lumbriculus variegatus were studied in a 23-d toxicity test. Artificially prepared sediments (pH 5 and 7) were spiked with varying concentrations of uncoated AgNP, polyvinylpyrrolidone (PVP)-coated AgNP, and silver nitrate (AgNO3 ) as dissolved Ag reference. Number of individuals and biomass change were used as endpoints for the toxicity. The toxic effects were related to the bioaccessible concentration of dissolved Ag in the sediments, assessed with a 2-step extraction procedure. The toxicity of 2 AgNPs was similar and greatly enhanced in the acidic sediment. Because the toxic effects were well related to the bioaccessible concentration of dissolved Ag in the sediments, the toxicity of sediment-associated AgNPs to L. variegatus is suggested to be a function of dissolved Ag rather than a result from NP-specific modes of toxicity. Environ Toxicol Chem 2018;37:1889-1897. © 2018 SETAC.

Kuusessa on muutakin hyödynnettävää kuin paperin ja kartongin valmistukseen tarvittava raaka-aine. Mielenkiinto on kohdistunut etenkin puun sisältämiin yhdisteisiin, joilla on havaittu olevan suotuisia terveydellisiä vaikutuksia. Tällainen on kuusen pihka, joka on useamman yhdisteen seos. Kuusen eri osien sisältämien yhdisteiden tutkimus on yhä ajankohtaisempaa. Esimerkiksi niin kuusesta kuin männystä saatavia antibiootteja tutkitaan Itä-Suomen yliopistossa. Repolar Pharmaceuticals Oy perustettiin vuonna 2006 pihkavalmisteiden tuotannon aloittamiseksi. Idea saatiin kotitekoisesta pihkasalvasta, jota yleisesti käytettiin Lapissa haavojen hoitoon. Repolar Pharmaceuticalsin tilaaman työn aiheena oli parantaa kuusen pihkan etanoliuuttomenetelmää. Nykyistä etanoliuuttotapaa haluttiin optimoida erilaisten parametrien avulla. Kirjallisessa osassa paneuduttiin kuusen pihkan koostumukseen, sen prosessointiin ja analytiikkaan. Luottamuksellisessa kokeellisessa osassa kyettiin löytämään tapoja, jotka paransivat saantoa ja nopeuttivat uuttoa. Pihka käsiteltiin pienentämällä raekokoa. Uuttoliuoksena oli etanoli. Tutkittavia tekijöitä olivat pihkan määrä verrattuna liuottimen määrään, liotus, ravistelu ja lämpötilan kohottaminen. Pihkaa uutettiin myös Soxhlet-uuttolaitteella. Tarkoituksena oli siis vertailla saantoja ja eri yhdisteiden uuttumista kuusen pihkasta ajan funktiona. Näytteet tutkittiin kaasukromatografisesti käyttäen liekki-ionisaatiodetektoria ja massaspektrometriä. Lisäksi määritettiin haihdutusjäännös- ja uuttoprosentti. Vertailunäytteenä tehtiin asetoniuutto, jonka tuloksia verrattiin muihin uuttotuloksiin.

Räjähdysaineiden kulkeutuminen maaperään ja vesitöihin aiheuttaa merkittävän ympäristöriskin, sillä toksikologisissa tutkimuksissa räjähdysaineiden on havaittu aiheuttavan monia terveydellisiä haittoja ja ne ovat myrkyllisiä eläville organismeille. Tämän johdosta räjähdysaineita sisältävien ympäristönäytteiden analysointiin on kehitetty monia menetelmiä, jotta koko ekosysteemiä kohtaavat vahingot voitaisiin tunnistaa ja suorittaa kunnostustoimenpiteitä kontaminoituneilla alueilla. Tässä Pro gradu-tutkielmassa tarkastellaan räjähdysaineita, niiden ympäristö- ja terveysvaikutuksia sekä räjähdysaineita sisältävien maanäytteiden uuttamista ja analysointia. Tutkielmassa selvitetään nestekromatografisen systeemin toimintaperiaate sekä käydään läpi analyysimenetelmien validointiin ja laadunvarmistukseen liittyviä asioita. Erikoistyössä verrattiin räjähdysaineita sisältävien maanäytteiden uuttamiseen käytettyjä kolmea näytteen esikäsittelymenetelmää. Näytteiden uuttaminen suoritettiin mekaanisella ravistelulla, nopeutetulla liuotinuutolla ja mikroaaltoavusteisella uutolla. Analyyttien pitoisuudet analysoitiin nestekromatografisesti ja yhdisteiden detektointi suoritettiin UV-detektorilla. Menetelmän validointi suoritettiin viiden validointiparametrin (selektiivisyys, spesifisyys, lineaarisuus, toistotarkkuus, oikeellisuus) avulla ja se soveltui hyvin maanäytteistä uutettujen analyyttien pitoisuusmäärityksiin. Esikäsittelymenetelmien välisessä vertailussa mekaaninen ravistelu todettiin suhteellisen tarkaksi ja toistettavaksi menetelmäksi, jolla on kohtalainen uutto-tehokkuus. Nopeutetussa liuotinuutossa uuttolaitteisto oli tekniseltä toiminta-varmuudeltaan huono, mutta se oli uuttotehokkuudeltaan paras. Mikroaalto-avusteinen uutto oli suhteellisen tarkka ja toistettava esikäsittelymenetelmä, mutta sen uuttotehokkuus oli huono, joten menetelmän optimointia on jatkettava tulevaisuudessa.