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In this study, phenolic compounds using deep eutectic solvents (DES) were extracted from cork dust, and the biogas production potential of DES-treated cork dust samples was determined. The DES treatment was carried out using choline chloride and formic acid (1:2 M ratio) at various temperatures (90, 110 and 130 °C) and treatment times (20, 40 and 60 min) at a solid-to-solvent ratio of 1:10 g mL -1 . The highest total phenolic content (137 mg gallic acid equivalent (GAE) g -1 dry cork dust) was achieved at 110 °C/20 min. The extracts exhibited an antioxidant capacity of up to 56.3 ± 3.1 % 1,1-diphenyl-2-picrylhydazyl (DPPH) inhibition at a dilution rate of 100. DES treatment resulted in minimal sugar solubilization at low temperatures, while approximately 42 % of the xylan fraction in the biomass degraded under severe conditions (e.g., 130 °C/60 min). Catechin, 4-hydroxybenzoic acid and gallic acid were the major phenolics in DES extracts. The biogas yield of DES-treated cork dust increased with treatment severity. The highest biogas yield (115.1mL N g VS -1 ) was observed at 130 °C/60 min, representing an increase of 125 % compared to the untreated sample. SEM images revealed that the surface structure of the samples became smoother after mild pretreatment and rougher after harsh pretreatment. Compositional and FTIR analyses indicated that a higher biogas formation potential was associated with increased cellulose content in the substrate, which could be attributed to hemicellulose solubilization in the hydrolysate. Overall, DES pretreatment effectively enhanced phenol extraction and anaerobic degradability., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Water-soluble xylans useable for many potential applications can be produced based on the hydrolysis of wheat straw within a fixed bed using saturated steam to provide a xylan-rich hydrolysate low in particles and lignin enabling an effective ultrafiltration and xylan separation. Under defined conditions (180 °C, 10 bar, 35 min), a degree of solubilization of 29.6 % for straw and of 63 % for hemicellulose is achieved. The dry mass of the resulting hydrolysate consists of at least 58 % xylose and arabinose. The xylose is mainly (87 %) present in non-monomeric form and appears to have a broad molecular weight distribution. Ultrafiltration with commercial membranes (4 to 50 kDa) is being investigated for the separation of the target fraction; here significant differences in the filtration behavior and rejections from 9 to 81 % for carbohydrates and from 13 to 48 % for phenolic compounds (lignin), respectively, are found., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

From a cost and sustainability perspective, the use of by-products such as rye bran in sow diets is of particular interest. Rye bran has valuable ingredients that have potential benefits for the gut health of sows. The aim of this study was to investigate the effects of including 15% rye bran in the sows' feed on the performance of sows and piglets. The feeding started one week before the farrowing date and ended at weaning. Performance was evaluated by measuring sow (n = 175) and piglet body weight (n = 1372) and sows' backfat thickness (n = 80). These data were additionally used to calculate the colostrum intake of the suckling piglets and the sows' milk production. It was found that there were no differences in the performance parameters between the experimental and control groups. However, this study showed that the piglets with light birth weight (LBW (<1000 g)) and medium birth weight (MBW (1000-1500 g) consumed more colostrum when the sows were fed rye bran (LBW: C/R 203.0 ± 39.2 g/214.3 ± 35.9 g; MBW: 291.3 ± 39.0 g/298.5 ± 36.4 g). It can be concluded that including 15% rye bran in the feed of lactating sows has no obvious negative effects on the performance of sows and piglets. Further studies are needed to evaluate the possible positive effects of rye bran.

Aim: Stillage, the main residue from cereal-based bioethanol production, offers a great potential for the recovery of pentosan-type carbohydrates. Therefore, potential process options for the recovery of pentosans from bioethanol thin stillage are investigated and their basic feasibility is demonstrated on a laboratory scale., Findings: The main result of this work is the development of a three-stage process for pentosan recovery, including solid-liquid separation, pentosan solubilisation and purification. The pentosan content of the thin stillage used here was determined to be about 14% related to dry matter (DM). By means of solid-liquid separation, these pentosans accumulate in the liquid phase (up to 80%), while the remainder (about 20%) is found in the solid phase. Solubilisation of these insoluble pentosans was achieved by using either a hydrothermal, an alkaline or an enzymatic treatment. Here, the results indicate a maximum solubilisation yield of 90% with a hydrothermal treatment using liquid hot water at 180 °C. Ultrafiltration and precipitation are investigated for purification. The most promising process option in this study is solid-liquid separation followed by ultrafiltration. In this case, the total pentosan yield is assessed to be about 48% (based on thin stillage) with a final pentosan concentration of about 30%DM., (© 2023. The Author(s).)

The nutritional benefits of rye (and therefore rye bran) are mainly due to its high content of fermentable dietary fiber, the non-starch polysaccharides (NSP). Microorganisms in the large intestine are able to convert these into short-chain fatty acids (SCFA), including butyrate. Butyrate strengthens the epithelial barrier function in the colon by nourishing the enterocytes and inhibiting the spread of Salmonella in the intestinal tract. Therefore, the aim of this study was to test under field conditions whether a diet with rye or rye bran as the main ingredient for gilts, sows, and weaned piglets is associated with a lower Salmonella prevalence. Depending on the age groups, between 20-30% rye or between 15-20% rye bran was used in the experimental group. A total of n = 1983 boot swabs, n = 356 fecal samples, and n = 1909 serum samples were examined. The results of this study show that rye or rye bran at the levels used had no apparent effect on the number of positive Salmonella samples. However, the Salmonella OD values in the experimental groups were significantly lower than in the control group. This suggests that the use of rye leads to a lower incidence of infection, but this effect could not be proven from swabs.

The cultivation of field crops necessarily produces large quantities of organic residues, which could be used for the production of biogas. However, this is only successfully possible if the operators of such biogas plants have sufficient expertise in running these plants, e.g. to avoid an overload of the biogas system. Against this background, the anaerobic degradability of various Egyptian agricultural residues is determined by laboratory testing; this includes both a determination of degradation behavior in batch tests and a feed analysis. The residues studied produce biogas yields ranging from 303 to 496 mL N g VS -1 . Co-digestion experiments demonstrate that hardly any interaction effects occur during the fermentation process for different mixtures of the investigated residues. Based on these findings, a model is developed to estimate biogas production using the investigated agricultural residues in continuous operation and to give recommendations for the optimal mode of operation., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

While bio-based but chemically synthesized polymers such as polylactic acid require industrial conditions for biodegradation, protein-based materials are home compostable and show high potential for disposable products that are not collected. However, so far, such materials lack in their mechanical properties to reach the requirements for, e.g., packaging applications. Relevant measures for such a modification of protein-based materials are plasticization and cross-linking; the former increasing the elasticity and the latter the tensile strength of the polymer matrix. The assessment shows that compared to other polymers, the major bottleneck of proteins is their complex structure, which can, if developed accordingly, be used to design materials with desired functional properties. Chemicals can act as cross-linkers but require controlled reaction conditions. Physical methods such as heat curing and radiation show higher effectiveness but are not easy to control and can even damage the polymer backbone. Concerning plasticization, effectiveness and compatibility follow opposite trends due to weak interactions between the plasticizer and the protein. Internal plasticization by covalent bonding surpasses these limitations but requires further research specific for each protein. In addition, synergistic approaches, where different plasticization/cross-linking methods are combined, have shown high potential and emphasize the complexity in the design of the polymer matrix.

In the EU, the transport sector is the only sector with increasing GHG emissions compared to 1990. While harmful emissions have decreased due to successful regulation, transport performance, fossil fuel consumption and thus CO 2 emissions have continued to increase, despite powertrain efficiency improvements. Meaningful regulation, which can be market-based (MBI) and non-market-based (NMBI) by nature, is needed to meet climate targets. To understand the mechanisms, effects and limitations of MBI and NMBI, this study investigates and evaluates selected regulations in the German road transportation sector until 2020. Therefore, this study identifies, describes, and categorizes environmental policy instrument types. Based on this step, selected instruments in the road transportation sector are identified by their type and implemented policies are described and assessed. Furthermore, an assessment methodology is developed to evaluate and score target achievement, cost-efficiency and practical feasibility by linking the outcomes of instruments to its goals. Based on the findings of this assessment, conclusions and recommendations are developed and discussed. Finally, results and general properties of policies and their type of instruments are extrapolated, and general statements about market and non-market-based instruments in a broader context for future regulation and market designs are projected. The study discovers that fuel producers and distributors, vehicle manufacturers and sellers are directly regulated by non-marked-based instruments, despite the EU Emissions Trading Scheme (ETS). On the customer side, primarily market-based implemented except for low-emission zones, which are direct regulations. The study finds that holistic representation and realistic internalization of external effects in a market is complex and will never be complete. Still, sufficient representation can be enough to drive transformation in the transport sector. The CO 2 price itself is not sufficiently representing the consequential costs of climate change induced by road transport, but it helps to make low-carbon alternatives economically viable. Overall, the study finds that most implemented regulations in the German road transport sector were successful in relation to their goals., Supplementary Information: The online version contains supplementary material available at 10.1186/s12302-022-00663-7., Competing Interests: Competing interestsThe authors declare that they have no competing interests., (© The Author(s) 2022.)

The economic viability of producing lignin by thermal-enzymatic treatment in a high-pressure fixed-bed reactor is investigated for the first time. In this direction, different advantages (e.g. recovery of low-odor sulfur-free lignin, high process flexibility) and disadvantages (e.g. high investment for high-pressure equipment) of this technology are considered. Regarding process flexibility, four different operating modes (i.e. flow through, circulation) are investigated by varying process parameters and applications of the C5 sugar fraction. Therefore, a combined modelling approach is applied by using overall biorefinery models and a predictive fixed-bed model. At optimum process conditions, lignin can be produced at a competitive price (395 €/t Lignin ) when comparing to other technical lignins. This result is achieved by using the fixed-bed reactor only for thermal treatment, with the water consumption being the most important factor affecting the cost of lignin production. Compared to that the C5 sugar recovery of the pretreatment is negligible., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

In order to minimize the environmental impacts of growing population, progressive exploitation of fossil resources and negative consequences of climate change the politically intended goal is to successively transform our primarily oil-based into a bio-based economy. Hence, one goal is to significantly reduce the utilization of fossil resources by increasing the use of renewable energy and resources (i.e. biomass) and the efficiency of their conversion processes. Including existing technologies into the development of future concepts could accelerate the transition to a bio-economy. As one solution integrated biorefinery concepts based on agricultural biogas plants are discussed, which convert biomass with minimal energy consumption to a multitude of products without generating waste. However, they still have huge potential in terms of increased biomass utilization. In that context, catch crops offer interesting opportunities as a substrate for those biorefineries, since they support soil regeneration while generating additional products for the bio-economy without increasing land use. In this study a selection of significant indicators was chosen in order to determine the environmental effectivity and economic efficiency of these biorefinery concepts by a systematic assessment of possible process schemes. Thus within this study the usability of the chosen indicators and the potential of catch crops in advanced biorefineries is assessed., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Amino acid analysis, commonly done by acid hydrolysis of proteins and HPLC analysis, faces one major problem: incomplete hydrolysis of stable amino acids and degradation of unstable amino acids are causing amino acid losses. As a result, amino acid recovery of unknown samples cannot be estimated. Some methods have been reported for correction of these factors in the past. This paper shows an improved and integrated method to overcome this problem by using stillage as an exemplary unknown sample material. Amino acid recovery from an unknown sample can be estimated by standard addition of a known protein. If the sample does not cause matrix effects during amino acid hydrolysis, recoveries of the standard protein are transferable to the sample. If the sample does cause matrix effects correction of amino acid losses can instead be done by determination of hydrolysis kinetics. Therefore, first order kinetics were used for amino acids that undergo degradation during hydrolysis. For all stable amino acids higher order kinetics were used, a novel approach to determine hydrolysis kinetics. The presented method can be a helpful tool for scientists who want to optimize amino acid analysis of a particular biomass substrate., (Copyright © 2017 Elsevier Inc. All rights reserved.)