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AbstractCellulose and lignin nanoparticles are high‐value‐added products obtained from lignocellulosic biomasses through several steps of cellulose purification and lignin extraction. These steps drastically reduce the potential feedstock revenue when carried out as stand‐alone methodologies. To increase biomass yields, we describe here a strategy to design a biorefinery focused on producing cellulose and lignin nanoparticles as main products, but also aim to recover and benefit from other biomass components using only water‐based processes. Sequential pressurized liquid extractions and diluted acid and alkaline treatments were carried out to fractionate elephant grass biomass, yielding (for every 100 g of biomass): 30 g of cellulose pulp (converted to 9 g of cellulose nanocrystals and 9 g of cellulose nanofibers); 10 g of lignin (used to produce 8.5 g of stable colloidal lignin nanoparticles by probe‐sonication in water); 7.5 g of extractives (e.g. sterols and phenolics) and 23 g of xylose (converted to 4.1 g of furfural). Alternatively, to allow for the flexible use of the cellulose fraction in the proposed biorefinery, 22 g of glucose could be produced by enzymatic hydrolysis. The results demonstrate that water‐based processes are suitable for a holistic use of biomass, providing a comprehensive set of high‐value‐added co‐products that are renewable and cost‐effective chemical, cosmetic, food, polymer and pharmaceutical solutions.

Lipase‐catalyzed transesterification of triglycerides and alcohols to obtain biodiesel is an environmentally friendly and sustainable route for fuels production since, besides proceeding in mild reaction conditions, it allows for the use of low‐cost feedstocks that contain water and free fatty acids, for example non‐edible oils and waste oils. This review article reports recent advances in the field and focus in particular on a major issue in the enzymatic process, the inactivation of most lipases caused by methanol, the preferred acyl acceptor used for alcoholysis. The recent results about immobilization of enzymes on nano‐materials and the use of whole‐cell biocatalysts, as well as the use of cell‐surface display technologies and metabolic engineering strategies for microbial production of biodiesel are described. It is discussed also insight into the effects of methanol on lipases obtained by modeling approaches and report on studies aimed at mining novel alcohol stable enzymes or at improving robustness in existing ones by protein engineering.

The aqueous extraction of orange peel waste (OPW), the byproduct of the juice extraction process generated annually in massive amounts (21 Mton), yields a carbohydrate-rich liquid fraction, termed orange peel extract (OPE). Several studies highlight that the combination of glycerol, a biodiesel byproduct, with carbohydrate mixtures might boost microbial lipid production. This study performed first a shaken flask screening of 15 oleaginous yeast strains based on their growth and lipid-producing abilities on OPE- and glycerol-based media. This screening enabled the selection of R. toruloides NRRL 1091 for the assessment of the process transfer in a stirred tank reactor (STR). This assessment relied, in particular, on either single- and double-stage feeding fed-batch (SSF-FB and DSF-FB, respectively) processes where OPE served as the primary medium and nitrogen-containing glycerol-OPE mixtures as the feeding one. The continuous supply mode at low dilution rates (0.02 and 0.01 h-1 for SSF-FB and DSF-FB, respectively) starting from the end of the exponential growth of the initial batch phase enabled the temporal extension of biomass and lipid production. The SSF-FB and DSF-FB processes attained high biomass and lipid volumetric productions (LVP) and ensured significant lipid accumulation on a dry cell basis (YL/X). The SSF-FB process led to LVP of 20.6 g L-1 after 104 h with volumetric productivity (r L) of 0.20 g L-1 h-1 and YL/X of 0.80; the DSF-FB process yielded LVP, r L and YL/X values equal to 15.92 g L-1, 0.11 g L-1 h-1 and 0.65, respectively. The fatty acid profiles of lipids from both fed-batch processes were not significantly different and resembled that of Jatropha oil, a vastly used feedstock for biodiesel production. These results suggest that OPE constitutes an excellent basis for the fed-batch production of R. toruloides lipids, and this process might afford a further option in OPW-based biorefinery.

This research sought to determine optimal corn waste stream-based fermentation medium C and N sources and incubation time to maximize pigment production by an indigenous Indonesian Penicillium spp., as well as to assess pigment pH stability.A Penicillium spp. was isolated from Indonesian soil, identified as Penicillium resticulosum, and used to test the effects of carbon and nitrogen type and concentrations, medium pH, incubation period and furfural on biomass and pigment yield (PY) in a waste corncob hydrolysate basal medium. Maximum red PY (497.03 ± 55.13 mg l(-1)) was obtained with a 21 : 1 C : N ratio, pH 5.5-6.0; yeast extract-, NH(4) NO(3)-, NaNO(3)-, MgSO(4) ·7H(2) O-, xylose- or carboxymethylcellulose (CMC)-supplemented medium and 12 days (25 °C, 60-70% relative humidity, dark) incubation. C source, C, N and furfural concentration, medium pH and incubation period all influenced biomass and PY. Pigment was pH 2-9 stable.Penicillium resticulosum demonstrated microbial pH-stable-pigment production potential using a xylose or CMC and N source, supplemented waste stream cellulose culture medium.Corn derived, waste stream cellulose can be used as a culture medium for fungal pigment production. Such application provides a process for agricultural waste stream resource reuse for production of compounds in increasing demand.

Non-timber forest products have often been held out as potential tools for conservation and sustainable development, but sustainability assessments are frequently difficult and time-consuming, especially in conflict areas. Thus, rapid assessments can be useful in providing a broad overview of the harvesting system in order to generate meaningful conservation or development recommendations. Here, we use rapid assessment methodology, including semi-structured interviews and direct observations, to examine the frankincense harvesting system in Somaliland in 2010 and again in 2016 and 2017. We identified significant levels of overharvesting, driven by a breakdown of the traditional management system. Demand for resin and resin prices increased dramatically from 2010 to 2017, at the same time as the tree populations were declining, resource tenure security was weakening, drug use was increasing, and the supply chain was becoming more complex. These factors combine to incentivize short-term unsustainable practices, and the lack of traceability and transparency prevents international buyers from meaningfully engaging with the system. However, new technologies and approaches being employed mean that buyers will soon be able to clearly direct their purchasing in order to incentivize sustainable practices and purchase resin in an ethical manner.

Tropical reforestation (TR) has been highlighted as an important intervention for climate change mitigation because of its carbon storage potential. TR can also play other frequently overlooked, but significant, roles in helping society and ecosystems adapt to climate variability and change. For example, reforestation can ameliorate climate‐associated impacts of altered hydrological cycles in watersheds, protect coastal areas from increased storms, and provide habitat to reduce the probability of species' extinctions under a changing climate. Consequently, reforestation should be managed with both adaptation and mitigation objectives in mind, so as to maximize synergies among these diverse roles, and to avoid trade‐offs in which the achievement of one goal is detrimental to another. Management of increased forest cover must also incorporate measures for reducing the direct and indirect impacts of changing climate on reforestation itself. Here we advocate a focus on “climate‐smart reforestation,” defined as reforesting for climate change mitigation and adaptation, while ensuring that the direct and indirect impacts of climate change on reforestation are anticipated and minimized.

Abstract Offshore cultivation of seaweed provides an innovative feedstock for biobased products supporting blue growth in northern Europe. This paper analyzes two alternative exploitation pathways: energy and protein production. The first pathway is based on anaerobic digestion of seaweed which is converted into biogas, for production of electricity and heat, and digestate, used as fertilizer; the second pathway uses seaweed hydrolysate as a substrate for cultivation of heterotrophic microalgae. As a result the seaweed sugars are consumed while new proteins are produced enhancing the total output. We performed a comparative Life Cycle Assessment of five scenarios identifying the critical features affecting resource efficiency and environmental performance of the systems with the aim of providing decision support for the design of future industrial scale production processes. The results show that all scenarios provide environmental benefits in terms of mitigation of climate change, with biogas production from dried Laminaria digitata being the most favorable scenario, quantified as −18.7*10 2 kg CO 2 eq./ha. This scenario presents also the lowest consumption of total cumulative energy demand, 1.7*10 4 MJ/ha, and even resulting in a net reduction of the fossil energy fraction, −1.9*10 4 MJ/ha compared to a situation without seaweed cultivation. All scenarios provide mitigation of marine eutrophication thanks to bioextraction of nitrogen and phosphorus during seaweed growth. The material consumption for seeded lines has 2–20 times higher impact on human toxicity (cancer) than the reduction achieved by energy and protein substitution. However, minor changes in cultivation design, i.e. use of stones instead of iron as ballast to weight the seeded lines, dramatically reduces human toxicity (cancer). Externalities from the use of digestate as fertilizer affect human toxicity (non-cancer) due to transfer of arsenic from aquatic environment to agricultural soil. However concentration of heavy metals in digestate does not exceed the limit established by Danish regulation. The assessment identifies seaweed productivity as the key parameter to further improve the performance of the production systems which are a promising service provider of environmental restoration and climate change mitigation.