Production of biofuel from lignocellulosic biomass is relatively low due to the limited knowledge about natural cell wall loosening and cellulolytic processes in plants. Industrial separation of cellulose fiber mass from lignin, its saccharification and alcoholic fermentation is still cost-ineffective and environmentally unfriendly. Assuming that the green transformation is inevitable and that new sources of raw materials for biofuels are needed, we decided to study cell death—a natural process occurring in plants in the context of reducing the recalcitrance of lignocellulose for the production of second-generation bioethanol. “Members of the enzyme families responsible for lysigenous aerenchyma formation were identified during the root hypoxia stress in Arabidopsis thaliana cell death mutants. The cell death regulatory genes, LESION SIMULATING DISEASE 1 (LSD1), PHYTOALEXIN DEFICIENT 4 (PAD4) and ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1) conditionally regulate the cell wall when suppressed in transgenic aspen. During four years of growth in the field, the following effects were observed: lignin content was reduced, the cellulose fiber polymerization degree increased and the growth itself was unaffected. The wood of transgenic trees was more efficient as a substrate for saccharification, alcoholic fermentation and bioethanol production. The presented results may trigger the development of novel biotechnologies in the biofuel industry.

Taking into account the circular economy guidelines and results of life cycle analyses of various materials, it was proposed to use a blackcurrant pomace filler in the production process of viscoelastic polyurethane (PUR) foams intended for application as mattresses, pillows, or elements for orthopedics. Open-cell viscoelastic PUR foams containing 10–60 per hundred polyols (php) blackcurrant pomace were prepared. It was found that after introducing the filler to the PUR foam formulation, the speed of the first stage of the foaming process significantly decreases, the maximum temperature achieved during the synthesis drops (by 30 °C for the foam containing 40 php of filler compared to unfilled foam), and the maximum pressure achieved during the synthesis of foam containing 20 php is reduced by approximately 57% compared to the foam without filler. The growth time of the foams increases with increasing the amount of introduced filler; for the foam containing 60 php, the time is extended even by about 24%. The effect of the filler on the physical, morphological, mechanical, and functional performances of PUR foam composites has been analyzed. The use of 60 php as the filler reduced the hardness of the foams by approximately 30% and increased their comfort factor from 3 to 5.

In situ extraction is a method for separating plant secondary metabolites from in vitro systems of plant biomass cultures. The study aimed to investigate the MTMS-based xerogels morphology effect on the growth kinetics and deoxyshikonin productivity in xerogel-supported in vitro culture systems of Rindera graeca hairy root. Cultures were supplemented with three types of xerogel, i.e., mesoporous gel, microporous gel, and agglomerated precipitate, in the disintegrated or monolithic form. Structure, oil sorption capacity, and SEM analyses for xerogel-based additives were performed. Application of monolithic macroporous xerogel resulted in the highest biomass proliferation, i.e., 5.11-fold fresh biomass increase after four weeks of the screening culture. The highest deoxyshikonin production (i.e., 105.03 µg) was noted when hairy roots were maintained with particles of disintegrated mesoporous xerogel. The detailed kinetics investigations (6-week culture) revealed the highest growth of hairy root biomass and secondary metabolite production, equaling 9.46-fold fresh weight biomass and 204.08 µg deoxyshikonin, respectively. MTMS-based xerogels have been recognized as selective biocompatible scaffolds for boosting the proliferation of transgenic roots or for productivity enhancement of naphthoquinones without detrimental effects on biomass growth, and their successful applicability in in situ removal of secondary plant metabolites has been experimentally confirmed.

Despite its unique properties (biocompatibility and nontoxicity), chitin itself has limited application. Chitin is completely insoluble in most organic or inorganic solvents what can be beneficial when chitin is investigated as a support for chromatography or enzyme immobilization. These applications require the particles to have an extensive outer surface with a large number of reactive ligands. The increase in specific surface area of chitin particles can be performed by dissolution in ionic liquid and precipitation with water. To increase the number of reactive ligands (amine groups), deacetylation of the surface of chitin particles is necessary. The deacetylation process can be carried out by an enzymatic process with the enzyme, chitin deacetylase. In our investigation, 21 ionic liquids were used for chitin particle structure modification followed by enzymatic deacetylation. Results proved positive effect of modifications with ionic liquid on enzymatic deacetylation of the chitin surface with chitin deacetylase. For 12 samples the deacetylation gave an increase in number of active ligands in comparison to natural chitin. The best results were observed for [Bmim][Br], [Emim][Cl] and [MPpip][Ac]. That could be correlated with an increase in outer surface area by increasing porosity of particles or by structural changes in chitin particles.

Pretreatment is an essential step in the conversion of lignocellulosic biomass into valuable products. It aims to increase the biomass susceptibility to enzymatic saccharification to generate fermentable monosaccharides. In this study, the efficiency of 2 % potassium hydroxide (KOH) solution used as a pretreating agent for various lignocellulosic feedstocks, such as corn straw, corncob, and poplar wood, was evaluated. The influence of the pretreatment time, which varied from 0.5 to 24 h at 50 °C, on the alteration of biomass composition was investigated, as well as the enzymatic digestibility. Finally, the overall sugar yields were determined. For corncob, the yield on average amounted to 453.9 ±18.9 mg·g ⁻¹ raw (untreated) biomass, regardless of the pretreatment time. The overall sugar yield for both the corn straw and poplar wood biomass increased with increased pretreatment time and ranged from 333.0 to 438.4 mg·g ⁻¹ raw biomass and from 123.2 to 215.7 mg·g ⁻¹ raw biomass, respectively. Based on the results obtained, the most appropriate pretreatment times for all types of biomass were proposed. The results of this study may be useful for the development of lignocellulosic biomass processing technology.

Production of biofuel from lignocellulosic biomass is relatively low due to the limited knowledge about natural cell wall loosening and cellulolytic processes in plants. Industrial separation of cellulose fiber mass from lignin, its saccharification and alcoholic fermentation is still cost-ineffective and environmental unfriendly. Assuming that the green transformation is inevitable and that the new sources of raw materials for biofuels are needed, we decided to study cell death - a natural process occurring in plants in a context of reducing the recalcitrance of lignocellulose for production of second generation bioethanol. “members of the enzyme families responsible for lysigenous aerenchyma formation were identified during the root hypoxia stress in Arabidopsis thaliana cell death mutants. The cell death regulatory genes, LESION SIMULATING DISEASE 1 (LSD1), PHYTOALEXIN DEFICIENT 4 (PAD4) and ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1) conditionally regulate the cell wall when suppressed in transgenic aspen. During four years of growth in the field the following effects were observed: lignin content was reduced, the cellulose fiber polymerization degree increased and the growth itself was unaffected. The wood of transgenic trees was more efficient as a substrate for saccharification, alcoholic fermentation and bioethanol production. The presented results may trigger the development of novel biotechnologies in the biofuel industry.