Cell wall composition and biomass saccharification potential of Sida hermaphrodita differ between genetically distant accessions

Localisation and structure of sclerenchyma fibres in the stem of Sida hermaphrodita (L.) Rusby

Contemporary consumers value more sustainable products, necessitating the sustainable use of plants, including fibre crops. Plant sclerenchyma fibres are a source of raw material used in various areas of human life. The present study was focused on analyses of sclerenchyma fibres in the Virginia mallow (Sida hermaphrodita (L.) Rusby). This energy plant, which is known for its many uses, was examined in terms of the location and differentiation of sclerenchyma fibres. They are present in the stem and are arranged in two rings formed by bundles with variable thickness. The structure of sclerenchyma fibres is typical of strengthening tissue. A characteristic trait of the studied species is the presence of various terminal fragments of dead cells in the sclerenchyma tissue. The surface of sclerenchyma fibres was examined using atomic force microscopy (AFM) for the first time. The analyses showed a varied surface sculpture of the fibre surface, depending on the method of preparation of the fibres before analyses. The study may constitute the basis for further investigations of the potential use of S. hermaphrodita sclerenchyma fibres, which may indicate a novel application of this plant. The potential use of a new source of sclerenchyma fibres obtained from the stem of S. hermaphrodita may support sustainable development.

Lignocellulose Treatment Using a Flow-Through Variant of OrganoCat Process

This study adapts the biphasic OrganoCat system into a flow-through (FT) reactor, using a heated tubular setup where a mixture of oxalic acid and 2-methyltetrahydrofuran (2-MTHF) is pumped through beech wood biomass. This method minimizes solvent-biomass contact time, facilitating rapid product removal and reducing the risk of secondary reactions. A comparative analysis with traditional batch processes reveals that the FT system, especially under severe conditions, significantly enhances extraction efficiency, yielding higher amounts of lignin and sugars with reduced solid residue. Notably, the FT system shows partial hydrolysis of the cellulose, which increases with temperature while not producing significant amounts of furfural or 5-HMF, indicating more efficient depolymerization of polysaccharides without substantial sugar degradation. A statistical design of experiments (DOE) using a Box-Behnken design elucidates the influence of process variables (time, solvent flow rate, temperature) on the yield. Key findings highlight reactor temperature as the dominant factor affecting yields, with process time showing a significant but less pronounced impact. This study demonstrates the potential of the FT OrganoCat system for efficient lignocellulosic biomass fractionation and represents an advancement towards continuous lignocellulose processing, contributing to our knowledge of process optimization for improved biorefinery applications.

Zero Waste Concept in Production of PLA Biocomposites Reinforced with Fibers Derived from Wild Plant (Spartium junceum L.) and Energy Crop (Sida hermaphrodita (L.) Rusby)

This research follows the principles of circular economy through the zero waste concept and cascade approach performed in two steps. Our paper focuses on the first step and explores the characteristics of developed biocomposite materials made from a biodegradable poly(lactic acid) polymer (PLA) reinforced with natural fibers isolated from the second generation of biomass (agricultural biomass and weeds). Two plants, Spartium junceum L. (SJL) and Sida hermaphrodita (SH), were applied. To enhance their mechanical, thermal, and antimicrobial properties, their modification was performed with environmentally friendly additives-linseed oil (LO), organo-modified montmorillonite nanoclay (MMT), milled cork (MC), and zinc oxide (ZnO). The results revealed that SH fibers exhibited 38.92% higher tensile strength than SJL fibers. Composites reinforced with SH fibers modified only with LO displayed a 27.33% increase in tensile strength compared to neat PLA. The addition of LO improved the thermal stability of both biocomposites by approximately 5-7 °C. Furthermore, the inclusion of MMT filler significantly reduced the flammability, lowering the heat release rate to 30.25%, and enabling the categorization of developed biocomposite in a group of flame retardants. In the second step, all waste streams generated during the fibers extraction process are repurposed into the production of solid biofuels (pellets, briquettes) or biogas (bio)methane.