Bioenergy Life Science (United States)

Peat soils pose critical limitations in agricultural productivity due to nutrient leaching and suboptimal nutrient availability. This study investigates the effectiveness of engineered slow-release fertilizer (SRF) formulations and geometries tailored to tropical sapric and hydrophobic peat, aiming to enhance nutrient retention and plant productivity. Two greenhouse experiments at IPB University evaluated the effects of slow-release fertilizers (SRFs) formulated from biomass compost combined with inorganic components (NPK, sludge, fly ash, and ammonium sulfate) using tapioca flour (5%) as a binder. The SRFs were first prepared and then applied to corn and bock choy. The testing encompassed varied fertilizer compositions and geometrical forms in pellet, crumble, small cylinder, and large cylinder. Cylinder formulation contributed to leaching mitigation, in which the nitrate leaching was improved from 0.14 to only 0.05 mg/m 2 in 2 days and from 1.62 to only 0.48 mg/m 2 in 35 days after application. The biomass compost-inorganic matrix proved instrumental in promoting nutrient synchronization with crop uptake, which could improve the biomass index from 0.32 at standard fertilizer to 1.20 with cylinder formulation. These findings highlight that strategic formulation and geometric design of SRF, can effectively reduce nutrient losses and substantially improve biomass growth and crop performance in peat-based agriculture.

Abstract Advancements in biofuel production technologies are essential for reducing global dependence on fossil fuels and addressing their overexploitation. Many valuable components of biomass, such as cellulose, hemicellulose, and lignin, remain underused in traditional biorefineries, which typically rely on a single feedstock to produce a primary biofuel. In contrast, integrated biorefineries utilize multiple feedstocks and various biomass conversion technologies, resulting in the production of numerous value‐added products and a significant waste reduction. This article reviews emerging biorefinery technologies, including fermentation, anaerobic digestion, densification, torrefaction, pyrolysis, liquefaction, and gasification. These technologies convert waste biomass into a variety of biofuels, such as bioethanol, biobutanol, biohydrogen, biogas, briquettes, biochar, bio‐oil, bio‐crude oil, and syngas. The review emphasizes the integration of biorefinery technologies, focusing on energy‐driven systems and closed‐loop waste utilization and management pathways. Additionally, the article discusses physical, chemical, and biological pretreatment techniques, along with the principles and unit operations associated with both biological and thermochemical biorefinery technologies. It also examines the logistics and supply chain necessary for biorefineries to effectively use diverse biomass sources and expand their biofuel production capabilities. Finally, the article concludes by addressing the need for integrated waste‐to‐energy conversion technologies that ensure process efficiency, byproduct utilization, maximum resource recovery, infrastructure compatibility, reduced carbon footprints, and circular economy strategies.

Lignin, the heterogeneous aromatic macromolecule found in the cell walls of vascular plants, is an abundant feedstock for the production of biochemicals and biofuels. Many valorization schemes rely on lignin depolymerization, with decades of research focused on accessing monomers through C-O bond cleavage, given the abundance of β-O-4 bonds in lignin and the large number of available C-O bond cleavage strategies. Monomer yields are, however, invariably lower than desired, owing to the presence of recalcitrant C-C bonds whose selective cleavage remains a major challenge in catalysis. In this Review, we highlight lignin C-C cleavage reactions, including those of linkages arising from biosynthesis (β-1, β-5, β-β and 5-5) and industrial processing (5-CH2-5 and α-5). We examine multiple approaches to C-C cleavage, including homogeneous and heterogeneous catalysis, photocatalysis and biocatalysis, to identify promising strategies for further research and provide guidelines for definitive measurements of lignin C-C bond cleavage.

BackgroundSensitivity to inhibitors derived from the pretreatment of plant biomass is a barrier to the consolidated bioprocessing of these complex substrates to fuels and chemicals by microbes. Spermidine is a low molecular weight aliphatic nitrogen compound ubiquitous in microorganisms, plants, and animals and is often associated with tolerance to stress. We recently showed that overexpression of the endogenous spermidine synthase enhanced tolerance of the Gram-positive bacterium, Clostridium thermocellum to the furan derivatives furfural and HMF.ResultsHere we show that co-expression with an NADPH-dependent heat-stable butanol dehydrogenase from Thermoanaerobacter pseudethanolicus further enhanced tolerance to furans and acetic acid and most strikingly resulted in an increase in thermotolerance at 65 °C.ConclusionsTolerance to fermentation inhibitors will facilitate the use of plant biomass substrates by thermophiles in general and this organism in particular. The ability to grow C. thermocellum at 65 °C has profound implications for metabolic engineering.

Woody biomass is an important feedstock for biofuel production. Manipulation of wood properties that enable efficient conversion of biomass to biofuel reduces cost of biofuel production. Wood cell wall composition is regulated at several levels that involve expression of transcription factors such as wood‐/secondary cell wall‐associated NAC domains (WND or SND). In Arabidopsis thaliana , SND1 regulates cell wall composition through activation of its down‐stream targets such as MYBs. The functional aspects of SND1 homologs in the woody Populus have been studied through transgenic manipulation. In this study, we investigated the role of PdWND1B, Populus SND1 sequence ortholog, in wood formation using transgenic manipulation through over‐expression or silencing under the control of a vascular‐specific 4‐coumarate‐CoA ligase (4CL) promoter. As compared with control plants, PdWND1B‐RNAi plants were shorter in height, with significantly reduced stem diameter and dry biomass, whereas there were no significant differences in growth and productivity of PdWND1B over‐expression plants. Conversely, PdWND1B over‐expression lines showed a significant reduction in cellulose and increase in lignin content, whereas there was no significant impact on lignin content of downregulated lines. Stem carbohydrate composition analysis revealed a decrease in glucose, mannose, arabinose, and galactose, but an increase in xylose in the over‐expression lines. Transcriptome analysis revealed upregulation of several downstream transcription factors and secondary cell wall related structural genes in the PdWND1B over‐expression lines, partly explaining the observed phenotypic changes in cell wall chemistry. Relative to the control, glucose release efficiency and ethanol production from stem biomass was significantly reduced in over‐expression lines. Our results show that PdWND1B is an important factor determining biomass productivity, cell wall chemistry and its conversion to biofuels in Populus.

Corresponding Standard Reference Material Data used in Partial Least Squares Regression Models for Sugar Composition Estimates in Biomass in: Economic Impact of Yield and Composition Variation in Bioenergy Crops: Populus trichocarpa (for corresponding manuscript: DOI: 10.1002/bbb.2148) PDF Files: Images of 1H NMR spectra for neutralized 2-stage acid hydrolysates of 4 NIST Standard Reference Material biomass samples (Monterey Pine 8493, Sugarcane Bagasse 8491, Wheat Straw 8494, and Eastern Cottonwood/Poplar 8492) and 2 Center for Bioenergy Innovation reference biomass samples (Poplar - Populus trichocarpa and Switchgrass - Panicum Virgatum). Suppression of the water peak was achieved using a NOESY-1D with presaturation, a recycle delay of 5 s, and a total of 64 scans. Spectra were acquired at 298 K and processed with automatic phase correction, baseline correction, and chemical shift referencing to TSP-d4. Images show all 1H data from 10 to 1ppm with inset spectra of region of interest (4.0 to 3.1 ppm). Text Files: Spectra for neutralized 2-stage acid hydrolysates of 4 NIST Standard Reference Material biomass samples (Monterey Pine 8493, Sugarcane Bagasse 8491, Wheat Straw 8494, and Eastern Cottonwood/Poplar 8492) and 2 Center for Bioenergy Innovation reference biomass samples (Poplar - Populus trichocarpa and Switchgrass - Panicum Virgatum) were converted into text files for plotting. Files contain 8192 points of raw spectral data from 12.23 to -2.78 ppm. The text file contains 4 columns of data and includes: Point number, Intensity, Hz, and ppm. Xcel Spreadsheet: HPLC measured monomeric sugar concentrations and bucketed 1H NMR data used to build monomeric sugar composition prediction models. Sugar composition in biomass determined from HPLC analyses are given in mg sugar/mg of biomass. Spectral bucketing was performed using Bruker’s AMIX software. Spectra were divided into 0.005 ppm buckets in the region of 3.10– 4.15 ppm for a total of 210 buckets. Headers for the bucketed data are the chemical shift in ppm of the center of the bucket. Bucketed data was used to build partial least squares models for subsequent predictions in The Unscrambler v. 10.5(CAMO A/S, Trondheim, Norway). The formation of methanol during hydrolysis interferes with the quantitative NMR analysis of sugars, so the methanol peak centered at 3.37 ppm and spanning four buckets (3.2925 – 3.2775 ppm) was set to zero for all spectra.

A new concept for the NASA Jet Propulsion Laboratory (JPL) All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) robotic constructor / mobility system employs tendon-driven actuation of individual limbs, similar to high-capacity cranes in terrestrial work environments, that can offload cargo from tall landers. While maintaining mechanical joints that allow each limb to function as a highly dexterous multi-Degree-Of-Freedom (DOF) robotic arm, tendon-driven truss sections increase the capacity of moment loads for extended configurations of the limb. The tendon-driven crane-like limb will be capable of offloading cargo from tall landers such as the SpaceX Starship. This paper describes the structural analysis, operations, calibration, and actuation of limbs designed to address specific target load cases that might be required for human exploration missions on planetary surfaces.

Orphan genes are characteristic genomic features that have no detectable homology to genes in any other species and represent an important attribute of genome evolution as sources of novel genetic functions. Here, we identified 445 genes specific to Populus trichocarpa. Of these, we performed deeper reconstruction of 13 orphan genes to provide evidence of de novo gene evolution. Populus and its sister genera Salix are particularly well suited for the study of orphan gene evolution because of the Salicoid whole-genome duplication event which resulted in highly syntenic sister chromosomal segments across the Salicaceae. We leveraged this genomic feature to reconstruct de novo gene evolution from intergenera, interspecies, and intragenomic perspectives by comparing the syntenic regions within the P. trichocarpa reference, then P. deltoides, and finally Salix purpurea. Furthermore, we demonstrated that 86.5% of the putative orphan genes had evidence of transcription. Additionally, we also utilized the Populus genome-wide association mapping panel, a collection of 1,084 undomesticated P. trichocarpa genotypes to further determine putative regulatory networks of orphan genes using expression quantitative trait loci (eQTL) mapping. Functional enrichment of these eQTL subnetworks identified common biological themes associated with orphan genes such as response to stress and defense response. We also identify a putative cis-element for a de novo gene and leverage conserved synteny to describe evolution of a putative transcription factor binding site. Overall, 45% of orphan genes were captured in trans-eQTL networks.