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Abstract The lignocellulosic biomass (LCB) is an attractive, sustainable, and environmentally friendly alternative to fossil sources to produce biofuel, biomaterials, and biochemicals. However, its recalcitrant and heterogenous structure challenges its biodegradation and valorization. The gut microbiome of soil invertebrate species has emerged as a rich source of LCB-degrading bacteria and enzymes in terrestrial ecosystems. The primary objective of this investigation was to identify the bacterial communities within the Porcellio dilatatus gut (Crustacea: Isopods), to obtain enriched cultures, and to identify bacterial isolates with LCB-degrading activity. A total of 112 enriched cultures were screened, all exhibiting xylanolytic activity. Among them, 94 displayed cellulolytic activity, 30 showed chitinolytic activity, and 21 demonstrated ligninolytic activity. Four enriched cultures were selected, and 128 bacteria with cellulolytic, xylanolytic, chitinolytic, or ligninolytic activity were isolated and taxonomically classified. The obtained results reinforce the potential of bacterial communities within the digestive tract of soil invertebrates as a valuable source of lignocellulose-degrading microorganisms. Thirty-one isolates underwent in-depth enzymatic characterization, and five were selected and functionally evaluated. An artificial bacterial consortium was constructed to assess the potential benefits of using consortia to achieve enhanced LCB degradation. The positive results of this proof-of-concept artificial consortium (PdG-AC) can be used in future applications and is a valuable tool for enzymatic and microbial consortia engineering by, e.g., changing growth conditions for enhanced LCB-degrading abilities. Key points • The gut microbiome of Porcellio dilatatus was characterized. • Porcellio dilatatus gut hosts many lignocellulose-degrading bacteria. • Developed an artificial bacterial consortium for lignocellulose degradation.

Biofuels derived from microalgae biomass have received a great deal of attention owing to their high potentials as sustainable alternatives to fossil fuels. Microalgae have a high capacity of CO2 fixation and depending on their growth conditions, they can accumulate different quantities of lipids, proteins, and carbohydrates. Microalgal biomass can, therefore, represent a rich source of fermentable sugars for third generation bioethanol production. The utilization of microalgal carbohydrates for bioethanol production follows three main stages: i) pretreatment, ii) saccharification, and iii) fermentation. One of the most important stages is the pretreatment, which is carried out to increase the accessibility to intracellular sugars, and thus plays an important role in improving the overall efficiency of the bioethanol production process. Diverse types of pretreatments are currently used including chemical, thermal, mechanical, biological, and their combinations, which can promote cell disruption, facilitate extraction, and result in the modification the structure of carbohydrates as well as the production of fermentable sugars. In this review, the different pretreatments used on microalgae biomass for bioethanol production are presented and discussed. Moreover, the methods used for starch and total carbohydrates quantification in microalgae biomass are also briefly presented and compared.

AbstractNutrient enrichment can simultaneously increase and destabilise plant biomass production, with co‐limitation by multiple nutrients potentially intensifying these effects. Here, we test how factorial additions of nitrogen (N), phosphorus (P) and potassium with essential nutrients (K+) affect the stability (mean/standard deviation) of aboveground biomass in 34 grasslands over 7 years. Destabilisation with fertilisation was prevalent but was driven by single nutrients, not synergistic nutrient interactions. On average, N‐based treatments increased mean biomass production by 21–51% but increased its standard deviation by 40–68% and so consistently reduced stability. Adding P increased interannual variability and reduced stability without altering mean biomass, while K+ had no general effects. Declines in stability were largest in the most nutrient‐limited grasslands, or where nutrients reduced species richness or intensified species synchrony. We show that nutrients can differentially impact the stability of biomass production, with N and P in particular disproportionately increasing its interannual variability.

Abstract Cellulosic biomass, which is basically a polymer of glucose, is the most abundant organic polymer on earth and there is significant interest in the development of advanced materials for its valorization through the waste-to-energy and water-to-chemical scenarios. Hence, a precise investigation of the monomer (glucose) electrooxidation in electrochemical reactors is a key starting point to tackle the whole cellulose and ultimately the entire biomass. To this end, we report herein new insights about the operation of a cogeneration direct alkaline glucose fuel cell (which includes an anion exchange membrane) that simultaneously produces electricity and mainly gluconate as the reaction product. The AuPt nanocatalysts of 3–5 nm particle size finely dispersed onto reduced graphene oxide (rGO) at a 20 wt% metal loading are obtained from an organic surfactant-free method, so-called the bromide anion exchange (BAE). Specifically, the electroanalytical investigation carried out with high-performance liquid ionic chromatography (HPLIC) and liquid chromatography coupled to mass spectrometry (LC-MS) demonstrate no carbon–carbon bond cleavage occurs, which represents an advance towards a CO2-free biomass valorization process. The comparison of the results commonly obtained in a three-electrode half-cell with those in an anion exchange membrane fuel cell shows that the trends in selectivity are the same. The fuel cell operation produces gluconate via a two-electron transfer process at 90% selectivity and 65% Faradaic efficiency. In addition to gluconate, glucuronate is also observed; both compounds are high value-added chemicals. This work contributes towards the engineering of novel electrocatalytic interfaces for the valorization of the surplus biomass into energy and chemicals.

Lignin is one of the most promising and versatile products obtained in biorefineries due to its diverse therapeutic properties such as antimicrobial, antioxidant and anti-inflammatory activity. However, these properties depend on the source of lignin and the way it was isolated from the biomass. In this study, four different lignins are compared (extracted with Aquasolv (ASL1, ASL2), Organosolv (OSL) and Alkali (ALK) processes) for their cellular antioxidant capacity, anti-diabetic activity, free radical scavenging and cytotoxicity. Alkali and Organosolv lignins showed the highest antioxidant capacity 1159.815 μmol TE g-1 and 1463.415 μmol TE g-1, respectively, in agreement with their highest amount of free -OH groups. Additionally, OSL showed the highest inhibition in the antidiabetic assay followed by ASL1 with values for α-amylase of 3.6 mg/ml and 4.3 mg/ml respectively, and α-glucosidase 1.6 mg/ml and 2.5 mg/ml correspondingly. Nevertheless, cell-based assays revealed that ASL has the lowest cytotoxic effect in Caco-2 cells and, thus, is 10 times less cytotoxic than Alkali and OSL. This work suggests the applicability of ASL for high value applications such as cosmetics or pharmaceuticals. INDUSTRIAL RELEVANCE: Industrially, Liquid Hot Water (LHW) and Organosolv processes may appear as promising biorefining technologies in the following years. Lignin produced is free of sulfur, can be labelled as clean and environmentally-friendly and in this study, was proven that LHW lignin is non cytotoxic. The findings in this paper showed that different sources of lignin can be used in product formulation for life science purposes, thus opening a broad spectrum of possibilities for lignin valorisation in biorefineries.

The extraction of phycobiliprotein (PBP) pigments from red algae Gracilaria gracilis was optimized using maceration, ultrasound-assisted extraction (ultrasonic water bath and ultrasonic probe), high pressure-assisted extraction, and freeze-thaw. The experimental conditions, namely homogenization time (t1), buffer concentration (C), treatment time (t2), biomass: buffer ratio (R), and pressure (P), were optimized using Response Surface Methodology (RSM). The yield of phycoerythrin (PE) extracted, determined spectroscopically, was used as the response variable. Maceration was the most efficient extraction method yielding 3.6 mg PE/g biomass under the optimal conditions (t1 = t2 = 10 min; C = 0.1 M; R = 1:50). Scanning Electron Microscopy (SEM) analysis of the biomass before and after the cell disruption treatments revealed a more efficient cell wall rupture with maceration.

Increasing forest wildfires in Portugal remain a growing concern since forests in the Mediterranean region are vulnerable to recent global warming and reduction of precipitation. Therefore, a long-term negative effect is expected on the vegetation, with increasing drought and areas burnt by fires. The strawberry tree (Arbutus unedo L.) is particularly used in Portugal to produce a spirit by processing its fruits and is the main income for forestry owners. Other applications are possible due to the fruit and leaves' anti-oxidant properties and bioactive compounds production, with a potential for clinical and food uses. It is a sclerophyllous plant, dry-adapted and fire resistant, enduring the Mediterranean climate, and recently considered as a possibility for afforestation, to intensify forest discontinuity where pines and eucalypts monoculture dominate the region. To improve our knowledge about the species' spatial distribution we used 318 plots (the centroid of a 1 km2 square grid) measuring the species presence and nine environmental attributes. The seven bioclimatic variables most impacting on the species distribution and two topographic features, slope and altitude, were used. The past, current and future climate data were obtained through WorldClim. Finally, the vulnerability of the strawberry tree to the effects of global climate change was examined in the face of two emission scenarios (RCP 4.5 and 8.5), to predict distribution changes in the years 2050 and 2070, using a species distribution models (MaxEnt). The reduction of suitable habitat for this species is significant in the southern regions, considering the future scenarios of global warming. Central and northern mountainous regions are putative predicted refuges for this species. Forest policy and management should reflect the impact of climate change on the usable areas for forestry, particularly considering species adapted to the Mediterranean regions and wildfires, such as the strawberry tree. The distribution of the species in the Last Glacial Maximum (LGM) and Mid-Holocene (MH) agrees with previous genetic and paleontological studies in the region, which support putative refuges for the species. Two in the southern and coastal-central regions, since the LGM, and one in the east-central mountainous region, considered as cryptic refugia.

The world is heading in the wrong direction on carbon emissions where we are not on track to limit global warming to 1.5 °C; Ireland is among the countries where overall emissions have continued to rise. The development of wettable peatland products and services (termed 'Paludiculture') present significant opportunities for enabling a transition away from peat-harvesting (fossil fuels) to developing 'green' eco-innovations. However, this must be balanced with sustainable carbon sequestration and environmental protection. This complex transition from 'brown to green' must be met in real time by enabling digital technologies across the full value chain. This will potentially necessitate creation of new green-business models with the potential to support disruptive innovation. This timely paper describes digital transformation of paludiculture-based eco-innovation that will potentially lead to a paradigm shift towards using smart digital technologies to address efficiency of products and services along with future-proofing for climate change. Digital transform of paludiculture also aligns with the 'Industry 5.0 - a human-centric solution'. However, companies supporting peatland innovation may lack necessary standards, data-sharing or capabilities that can also affect viable business model propositions that can jeopardize economic, political and social sustainability. Digital solutions may reduce costs, increase productivity, improve produce develop, and achieve faster time to market for paludiculture. Digitisation also enables information systems to be open, interoperable, and user-friendly. This constitutes the first study to describe the digital transformation of paludiculture, both vertically and horizontally, in order to inform sustainability that includes process automation via AI, machine learning, IoT-Cloud informed sensors and robotics, virtual and augmented reality, and blockchain for cyber-physical systems. Thus, the aim of this paper is to describe the applicability of digital transformation to actualize the benefits and opportunities of paludiculture activities and enterprises in the Irish midlands with a global orientation.