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Dihydrochalcones are a class of secondary metabolites, for which demand in biological and pharmacological applications is still growing. They posses several health-endorsing properties and, therefore, are promising candidates for further research and development. However, low content of dihydrochalcones in plants along with their low solubility and bioavailability restrict the development of these compounds as clinical therapeutics. Therefore, chemomicrobial and enzymatic modifications are required to expand their application. This review aims at analyzing and summarizing the methods of obtaining dihydrochalcones and of presenting their pharmacological actions that have been described in the literature to support potential future development of this group of compounds as novel therapeutic drugs. We have also performed an evaluation of the available literature on beneficial effects of dihydrochalcones with potent antioxidant activity and multifactorial pharmacological effects, including antidiabetic, antitumor, lipometabolism regulating, antioxidant, anti-inflammatory, antibacterial, antiviral, and immunomodulatory ones. In addition, we provide useful information on their properties, sources, and usefulness in medicinal chemistry.

The study focuses on the synthesis of Fe3O4@SiO2-NH2-Au heterostructures with magneto-plasmonic properties composed of well-defined cubic Fe3O4 cores (79 nm) covered with 10 nm silica shell and gold nanoparticles (8 nm) fabricated on silica shell. The surface-anchored MHDA (16-mercaptohexadecanoic acid) linker facilitated cellulase bioconjugation, which was confirmed through Raman spectroscopy. The presence of gold nanoparticle islands on the heterostructure enabled surface-enhanced Raman scattering (SERS), demonstrating the potential for bioactive substance identification. Immobilization of cellulase allowed for pH enhancement and enzyme thermal stability. The optimal pH shifted from 4.0 (free enzyme) to 6.0 while thermal stability increased by 20 °C. The immobilized cellulase kept its 49% activity after five hydrolysis cycles, compared to significantly lower activity for free cellulase. The proposed heterostructures for cellulase immobilization demonstrate potential for practical applications.

Microalgae are freshwater and marine unicellular photosynthetic organisms that utilize sunlight to produce biomass. Due to fast microalgal growth rate and their unique biochemical profiles and potential applications in food and renewable energy industries, the interest in microalgal research is rapidly increasing. Biochemical and genetic engineering have been considered to improve microalgal biomass production but these manipulations also limited microalgal growth. The aim of the study was the biochemical characterization of recently identified microalgal strain Planktochlorella nurekis with elevated cell size and DNA levels compared to wild type strain that was achieved by a safe non-vector approach, namely co-treatment with colchicine and cytochalasin B (CC). A slight increase in growth rate was observed in twelve clones of CC-treated cells. For biochemical profiling, several parameters were considered, namely the content of proteins, amino acids, lipids, fatty acids, β-glucans, chlorophylls, carotenoids, B vitamins and ash. CC-treated cells were characterized by elevated levels of lipids compared to unmodified cells. Moreover, the ratio of carotenoids to chlorophyll a and total antioxidant capacity were slightly increased in CC-treated cells. We suggest that Planktochlorella nurekis with modified DNA levels and improved lipid content can be considered to be used as a dietary supplement and biofuel feedstock.

In this study, 10 different plant materials (seeds/beans) were fermented by Bacillus subtilis var. natto. The influence of the process on vitamin K2 MK-7 content during different fermentation periods was assessed. Fermented plant samples were analyzed by the procedure using HPLC UV/DAD. The fermented sunflower seeds, mung beans and peas appeared to be the most promising plants, reaching values of K2 of 1080.18±55.11 µg/100g, 806.45±60.95 µg/100g and 636.92±59.86 µg/100g, respectively. The experiments showed that extending of the fermentation time to 5–6 days was favorable for the menaquinone-7 yield. The results show that almost all fermented seeds/beans, apart from soybean, can be good source of vitamin K2 MK-7 and represent a new perspective, especially in terms of lower the phytoestrogen content.

Cholesterol oxidase (ChOX) enzyme is one of the most important analytical enzyme, used for cholesterol assay in clinical diagnostics as well as food production, and the developing of innovative solutions for improving the selectivity and accuracy of the analysis including bio-nanotechnological approaches is still ongoing. The Surface Plazmon Resonance (SPR) and the surface enhanced Raman scattering (SERS) as specific for nanocurriers effects were observed what enable us to research the oscillation spectra of the ChOX enzyme. The vibrational lines are attributed to chemical functional groups existing in enzyme, for example, amino acids, amide groups as well as for cofactor. For the improving the SERS effect the gold nanoparticles – ChOX bionanocomplexes were analyzed in combination with gold-coating gratings as a promising plazmonic material.

The study focuses on the synthesis of Fe[sub.3]O[sub.4]@SiO[sub.2]-NH[sub.2]-Au heterostructures with magneto-plasmonic properties composed of well-defined cubic Fe[sub.3]O[sub.4] cores (79 nm) covered with 10 nm silica shell and gold nanoparticles (8 nm) fabricated on silica shell. The surface-anchored MHDA (16-mercaptohexadecanoic acid) linker facilitated cellulase bioconjugation, which was confirmed through Raman spectroscopy. The presence of gold nanoparticle islands on the heterostructure enabled surface-enhanced Raman scattering (SERS), demonstrating the potential for bioactive substance identification. Immobilization of cellulase allowed for pH enhancement and enzyme thermal stability. The optimal pH shifted from 4.0 (free enzyme) to 6.0 while thermal stability increased by 20 °C. The immobilized cellulase kept its 49% activity after five hydrolysis cycles, compared to significantly lower activity for free cellulase. The proposed heterostructures for cellulase immobilization demonstrate potential for practical applications.

Three methods of cellulose-derived polyol synthesis were elaborated. The suitable substrates were (hydroxypropyl)cellulose or cellulose, which were hydroxyalkylated in reactions with glycidol and ethylene carbonate in triethylene glycol or in water. The products were characterized by IR, 1H NMR, and MALDI ToF spectroscopies. For all polyols, IR spectra showed strong bands at 1060 cm−1 from the ether group formed upon the ring opening of GL and EC. The polyol obtained from (hydroxypropyl)cellulose in the triethylene glycol solvent was accompanied by oligomeric products of glycol hydroxyalkylation and oligomeric glycidol. The polyol obtained by the hydroxyalkylation of cellulose with glycidol and ethylene carbonate in the water contained units of hydroxyalkylated cellulose and products of hydroxyalkylation of water. The physical properties of the obtained polyols, like density, viscosity, and surface tension, were determined. The polyols were then used to obtain rigid polyurethane foams. The foams have apparent density, water uptake, and polymerization shrinkage similar to classic rigid PUFs. The foams showed advantageous thermal resistance in comparison with classic ones. After thermal exposure, their compressive strength improved. The biodegradation of the obtained materials was tested by a respirometric method in standard soil conditions by the measurement of biological oxygen demand and also using the cellulases or the enzymes responsible for cellulose degradation. It has been found that polyols are totally biodegradable within one month of exposure, while the foams obtained thereof are at least 50% biodegraded in the same conditions. The enzymatic biodegradation of the PUFs by the action of microbial cellulase was confirmed.

The study focuses on the synthesis of Fe O @SiO -NH -Au heterostructures with magneto-plasmonic properties composed of well-defined cubic Fe O cores (79 nm) covered with 10 nm silica shell and gold nanoparticles (8 nm) fabricated on silica shell. The surface-anchored MHDA (16-mercaptohexadecanoic acid) linker facilitated cellulase bioconjugation, which was confirmed through Raman spectroscopy. The presence of gold nanoparticle islands on the heterostructure enabled surface-enhanced Raman scattering (SERS), demonstrating the potential for bioactive substance identification. Immobilization of cellulase allowed for pH enhancement and enzyme thermal stability. The optimal pH shifted from 4.0 (free enzyme) to 6.0 while thermal stability increased by 20 °C. The immobilized cellulase kept its 49% activity after five hydrolysis cycles, compared to significantly lower activity for free cellulase. The proposed heterostructures for cellulase immobilization demonstrate potential for practical applications.

Regarding the limited resources for fossil fuels and increasing global energy demands, greenhouse gas emissions, and climate change, there is a need to find alternative energy sources that are sustainable, environmentally friendly, renewable, and economically viable. In the last several decades, interest in second-generation bioethanol production from non-food lignocellulosic biomass in the form of organic residues rapidly increased because of its abundance, renewability, and low cost. Bioethanol production fits into the strategy of a circular economy and zero waste plans, and using ethanol as an alternative fuel gives the world economy a chance to become independent of the petrochemical industry, providing energy security and environmental safety. However, the conversion of biomass into ethanol is a challenging and multi-stage process because of the variation in the biochemical composition of biomass and the recalcitrance of lignin, the aromatic component of lignocellulose. Therefore, the commercial production of cellulosic ethanol has not yet become well-received commercially, being hampered by high research and production costs, and substantial effort is needed to make it more widespread and profitable. This review summarises the state of the art in bioethanol production from lignocellulosic biomass, highlights the most challenging steps of the process, including pretreatment stages required to fragment biomass components and further enzymatic hydrolysis and fermentation, presents the most recent technological advances to overcome the challenges and high costs, and discusses future perspectives of second-generation biorefineries.

Some organosilicon compounds, including alkoxysilanes and siloxanes, proved effective in stabilizing the dimensions of waterlogged archaeological wood during drying, which is essential in the conservation process of ancient artifacts. However, it was difficult to determine a strong correlation between the wood stabilizing effect and the properties of organosilicon compounds, such as molecular weight and size, weight percent gain, and the presence of other potentially reactive groups. Therefore, to better understand the mechanism behind the stabilization effectiveness, the reactivity of organosilicons with wood polymers was studied using a 2D 1H–13C solution-state NMR technique. The results showed an extensive modification of lignin through its demethoxylation and decarbonylation and also the absence of the native cellulose anomeric peak in siloxane-treated wood. The most substantial reactivity between wood polymers and organosilicon was observed with the (3-mercaptopropyl)trimethoxysilane treatment, showing complete removal of lignin side chains, the lowest syringyl/guaiacyl ratio, depolymerization of cellulose and xylan, and reactivity with the C6 primary hydroxyls in cellulose. This may explain the outstanding stabilizing effectiveness of this silane and supports the conclusion that extensive chemical interactions are essential in this process. It also indicates the vital role of a mercapto group in wood stabilization by organosilicons. This 2D NMR technique sheds new light on the chemical mechanisms involved in organosilicon consolidation of wood and reveals what chemical characteristics are essential in developing future conservation treatments.