Hasil untuk "Chemical industries"

YaoKun Lei, Yi Isaac Yang

Chemical reaction sampling critically depends on collective variables (CVs) that capture the slow degrees of freedom governing reactive transformations. However, existing reaction CVs are often defined in geometric space or learned in a system-specific manner, which limits their transferability and leaves open the more fundamental question of how reaction progress should be represented. From a physical perspective, chemical reactions are defined by electron redistribution. Here, we introduce a charge-space electronic collective variable that describes the electronic component of reaction progress in a common linear form based on atomic charges. To enable its use in enhanced sampling, atomic charges and the corresponding CV gradients are provided by a neural-network model trained on QM/MM data within an iterative sampling-training workflow. Across multiple reactions in aqueous and enzymatic environments, we show that this electronic CV can be constructed in a common charge-space form, with the corresponding coefficients assigned in a simple manner from charge differences between relevant states. Our simulations further show that reaction progress generally involves coupled electronic and conformational components, and that the same framework can also be extended to restrain side reactions. These findings support charge-based electronic CVs as a physically motivated framework for describing the electronic component of chemical reaction progress with reduced reliance on handcrafted geometric descriptors.

Sonia Tassone, Rabeb Issaoui, Valentina Balestra et al.

Microplastic (MP) pollution is an emerging concern in ruminant production, as animals are exposed to MPs through air, water, and feeds. Ruminants play a key role in MP transmission to humans via animal products and contribute to MP return to agricultural soil through excreta. Identifying effective strategies to mitigate MP pollution in the ruminant sector is crucial. A promising yet understudied approach involves the potential ability of rumen microbiota to degrade MPs. This study investigated the in vitro ruminal degradation of three widely distributed MPs—low-density polyethylene (LDPE), polyethylene terephthalate (PET), and polyamide (PA)—over 24, 48, and 72 h. PET MP exhibited the highest degradation rates (24 h: 0.50 ± 0.070%; 48 h: 0.73 ± 0.057%; and 72 h: 0.96 ± 0.082%), followed by LDPE MP (24 h: 0.03 ± 0.020%; 48 h: 0.25 ± 0.053%; and 72 h: 0.56 ± 0.066%) and PA MP (24 h: 0.10 ± 0.045%; 48 h: 0.02 ± 0.015%; and 72 h: 0.14 ± 0.067%). These findings suggest that the ruminal environment could serve as a promising tool for LDPE, PET, and PA MPs degradation. Further research is needed to elucidate the mechanisms involved, potentially enhancing ruminants’ natural capacity to degrade MPs.

Izabela Queiroz Silva, Bruno Roswag Machado, Tamires Machado Ferreira et al.

The use of external triggers in microalgae cultivation has emerged as a promising approach to enhance biomass production and biochemical composition. For instance, magnetic fields (MFs) have had their potential to modulate cellular metabolism and physiological responses explored. This study investigated the effects of MF exposure on <i>Dunaliella salina</i> and evaluated its impact on biomass production, pigment synthesis and biochemical composition. The highest biomass concentration (0.59 g L⁻¹) was observed under continuous exposure to 60 mT (MF60-24 h); it represented a 51% increase in comparison with the control. A gradual rise in pH, which reached 10.83, was observed during cultivation. MF exposure also enhanced chlorophyll-a (118%) and carotenoid (95%) concentrations; thus, it improved photosynthetic efficiency and potential oxidative stress responses. The biochemical composition revealed a shift in metabolic pathways after prolonged MF exposure (24 h d⁻¹), decreasing carbohydrate content by 7%, while increasing lipid accumulation by 7%. Scanning electron microscopy (SEM) indicated structural modifications on the cell surface induced by the MF. Therefore, MF applications improve <i>D</i>. <i>salina</i> cultivation and enhance biomass composition for biotechnological applications.

Qiburi He, Shaofeng Su, Riqilang Ao et al.

IntroductionL-methionine is nutritionally indispensable for humans and animals. It is widely applied to feed, livestock and poultry breeding, food, medicine, energy and chemical industries. Maize endosperm contains a stable protein called δ-zein, which is abundant in sulfur amino acids, including methionine. Candida utilis (C. utilis) has been utilized as a cell factory to express and produce recombinant products. However, there is limited information on its genetic background and expression regulatory elements.MethodsIn this study, we aimed to improve methionine yields in an engineered C. utilis harboring the δ-zein gene by identifying a strong promoter and optimal signal peptide. A C. utilis glyceraldehyde-3-phosphate dehydrogenase (GAP) promoter mutant library was constructed and screened to obtain a strong promoter. Subsequently, de novo sequencing of the C. utilis genome was performed using a combination of second-generation Illumina-Seq sequencing platform and third-generation nanopore sequencing technique. Endogenous signal peptides of C. utilis were analyzed by sequencing the C. utilis genome. Recombinant C. utilis strains with homologous integration expression vectors of different signal peptides were constructed and screened for C. utilis optimal signal peptides for secretion of δ-zein.ResultsFinally, a secretory expression system pGS-zein containing a strong promoter GP6 and an optimal signal peptide SP8 was constructed. In the food-grade engineered C. utilis C/pGS-zein methionine content increased by 21.09% compared with that of C/psP with the original promoter, and by 33.64% compared to wild-type C. utilis.DiscussionThis study demonstrates successful expression and secretion of δ-zein in C. utilis and establishes a foundation for enhanced methionine production of heterologous proteins in C. utilis. More importantly, these high-performance biological elements provide fundamental knowledge and technical knowhow for enhanced production of heterologous proteins in C. utilis.

Hisham Ahmed, Rasaq S. Abolore, Swarna Jaiswal et al.

With growing concern over environmental sustainability and dwindling fossil resources, it is crucial to prioritise the development of alternative feedstocks to replace fossil resources. Spent coffee grounds (SCGs) are an environmental burden with an estimated six million tons being generated on a wet basis annually, globally. SCGs are rich in cellulose, lignin, protein, lipids, polyphenols and other bioactive compounds which are important raw materials for use in industries including pharmaceuticals and cosmetics. Furthermore, the energy sector has the potential to capitalize on the high calorific value of SCGs for biofuel and biogas production, offering a sustainable alternative to fossil fuels. SCGs are readily available, abundant, and cheap, however, SCGs are currently underutilized, and a significant amount are dumped into landfills. This review explores the potential of SCGs as a source of a value-added compound through various conversion technologies employed in the valorisation of SCGs into biochar, biofuel, and important chemical building blocks. The state-of-the-art, current knowledge, future research to stimulate the creation of sustainable products, and the challenges and economic feasibility of exploring SCGs in a biorefinery context are presented.

Romy Brödner, Karoline Fürst

Abstract In response to global challenges like climate change and resource depletion, national and international policies are increasingly emphasising sustainability. The bioeconomy represents a promising field to reconcile environmental integrity with economic development. The objective of this study is to examine the role of renewable resources in the construction industry within the framework of the bioeconomy, with a particular focus on Sustainable Development Goal 11: ‘Sustainable cities and communities’. The case study analyses the practical challenges and opportunities for innovation in Central Germany through a comprehensive regional analysis of construction practices using renewable resources. The methodology involved monitoring biomass flows by assessing harvest yields, area shares and biomass potentials. It also analysed the importance of the bio-based economy by examining employment data and identifying potential growth sectors. Stakeholder engagement was facilitated through knowledge transfer workshops to encourage collaboration and innovation. The results of the study highlight key trends within the industry, including the increasing prevalence of timber buildings, wood as a renewable carbon source in the chemical industry and the growing demand for wood-based packaging solutions. Policy initiatives are playing a supportive role in driving these developments, taking advantage of the region’s extensive wood resources (14.7 million m3 harvested in 2021) and the significant employment contribution of the forestry, wood and construction industries (2% of total employment, representing no less than 81,506 employees). These figures demonstrate the potential for sustainable construction practices to drive local economic growth and contribute to wider environmental objectives.

Jeannette Jacqueline Lucejko, Katja Tikka, Jakub Brózdowski et al.

The COST EU-PoTaRCh Action establishes a network focused on the past, present, and future significance, production, and use of major forest by-products in Europe and beyond. The Action centers around forest by-products—primarily potash, tar, resin, and charcoal (PoTaRCh), along with plant extracts—which have been produced and utilized for over 100,000 years due to their unique chemical, biological, and therapeutic properties. The primary goal of the Action is to demonstrate the importance of these products for the socio-economic development of European countries and beyond, as well as their impact on biodiversity and the natural environment. The Action's objectives are organized into five Working Groups (WGs), each aligned with specific areas of interest: heritage, chemical characterization, archaeology, environmental history, and future perspectives of PoTaRCh materials. A key aspect of the Action is its support for stakeholders outside the scientific community who possess knowledge of PoTaRCh products through their use in industries such as production, education, and the promotion of forests' natural and cultural heritage. In doing so, the Action brings together stakeholders with diverse activity profiles, including museums, state forests, the forestry industry, associations dedicated to preserving traditions, and the tourism sector. The EU-PoTaRCh Action adheres to the three key principles of COST’s inclusiveness policy: participation of inclusiveness target countries, gender balance, and the involvement of young researchers, including in leadership positions.

Asmaa Hussein Zaki, Hanaa Salem Saleh Gazwi, Moaz Mohamed Hamed et al.

The study explores the potential of orange peel extract (OPE) as a versatile natural resource, focusing on its phenolic composition, antioxidant, and antibacterial properties, as well as its application in fortifying yogurt. Analysis revealed significant concentrations of phenolic compounds in OPE. OPE exhibited notable antibacterial efficacy against pathogenic bacteria, particularly marine Escherichia coli, with synergistic effects observed when combined with Amikacin. Incorporating OPE into yogurt led to changes in chemical composition, enhancing total proteins, fat, and ash content. Fortified yogurt showed increased antioxidant activity and potential anti-cancer properties against HCT116 cell lines. In conclusion, OPE emerges as a rich source of bioactive compounds with diverse applications, from its antioxidant and antibacterial properties to its potential in fortifying functional foods like yogurt. This comprehensive exploration provides valuable insights into the multifaceted benefits of OPE, paving the way for its utilization in various industries and health-related applications.

Kyu-Sung Han, Se-Hun Yang, Yu-Jong Choi et al.

Zircon (ZrSiO4) is widely utilized as an opacifying agent in the glazes of sanitary-ware and ceramic tile. Zircon is dispersed in the glassy phase during the manufacture process of glaze, contributing a high refractive index and enhanced mechanical properties. However, significant price fluctuation and natural radioactivity of zircon have motivated extensive research to find alternative compositions. This study investigates the surface characteristics and radiation properties of sanitary-ware glazes prepared by replacing zircon with SnO2 and CaTiO3 in the raw materials. Analysis of the radioactivity index (Iγ) for glaze raw materials revealed that zircon exhibited the radioactivity index of 9.7, which is significantly higher than that of other mineral-based raw materials. To reduce the radiation emission from glaze, zircon was replaced with CaTiO3 and SnO2, which are radiation-free materials. The glaze prepared using CaTiO3 and SnO2 showed thermal behavior and surface characteristics comparable to those of zircon-containing glaze. Furthermore, the radioactivity index of clay specimen coated with zircon-containing glaze was measured at 1.09, while the radioactivity index of clay specimen coated with zircon-free glaze was significantly reduced to 0.62.

Spiros Paramithiotis, Jayanta Kumar Patra, Yorgos Kotseridis et al.

Fermented beverages have been a constant companion of humans throughout their history. A wide range of products have been developed with time, depending on the availability of raw materials and ambient conditions. Their differentiation was based on the specific characteristics of each product, resulting from the cultivation of different varieties and the variability of environmental conditions and agricultural practices, collectively described by the term ‘terroir’ that was developed in winemaking. The health benefits that have been associated with their consumption, which include the control of blood pressure and glycemic control, along with immunomodulatory, hypocholesterolemic, hepatoprotective, and antiproliferative activities, directed their re-discovery that occurred over the last few decades. Thus, the dynamics of the microbial communities of fermented beverages during fermentation and storage have been thoroughly assessed. The functional potential of fermented beverages has been attributed to the chemical composition of the raw materials and the bioconversions that take place during fermentation and storage, due to the metabolic capacity of the driving microbiota. Thus, the proper combination of raw materials with certain microorganisms may allow for the modulation of the organoleptic properties, as well as enrichment with specific functional ingredients, enabling targeted nutritional interventions. This plasticity of fermented beverages is their great advantage that offers limitless capabilities. The present article aims to critically summarize and present the current knowledge on the microbiota and functional potential of fermented beverages and highlight the great potential of these products.

Georgios Tsekenis, Giulio Cimini, Marinos Kalafatis et al.

We define bipartite and monopartite relational networks of chemical elements and compounds using two different datasets of inorganic chemical and material compounds, as well as study their topology. We discover that the connectivity between elements and compounds is distributed exponentially for materials, and with a fat tail for chemicals. Compounds networks show similar distribution of degrees, and feature a highly-connected club due to oxygen. Chemical compounds networks appear more modular than material ones, while the communities detected reveal different dominant elements specific to the topology. We successfully reproduce the connectivity of the empirical chemicals and materials networks by using a family of fitness models, where the fitness values are derived from the abundances of the elements in the aggregate compound data. Our results pave the way towards a relational network-based understanding of the inherent complexity of the vast chemical knowledge atlas, and our methodology can be applied to other systems with the ingredient-composite structure.

Victor Sabanza Gil, Andres M. Bran, Malte Franke et al.

The prediction of chemical reactions has gained significant interest within the machine learning community in recent years, owing to its complexity and crucial applications in chemistry. However, model evaluation for this task has been mostly limited to simple metrics like top-k accuracy, which obfuscates fine details of a model's limitations. Inspired by progress in other fields, we propose a new assessment scheme that builds on top of current approaches, steering towards a more holistic evaluation. We introduce the following key components for this goal: CHORISO, a curated dataset along with multiple tailored splits to recreate chemically relevant scenarios, and a collection of metrics that provide a holistic view of a model's advantages and limitations. Application of this method to state-of-the-art models reveals important differences on sensitive fronts, especially stereoselectivity and chemical out-of-distribution generalization. Our work paves the way towards robust prediction models that can ultimately accelerate chemical discovery.

Jiang-Xing Chen, Jia-Qi Hu, Raymond Kapral

Synthetic active colloidal systems are being studied extensively because of the diverse and often unusual phenomena these nonequilibrium systems manifest, and their potential applications in fields ranging from biology to material science. Recent studies have shown that active colloidal motors that use enzymatic reactions for propulsion hold special promise for applications that require motors to carry out active sensing tasks in complicated biomedical environments. In such applications it would be desirable to have active colloids with some capability of computation so that they could act autonomously to sense their surroundings and alter their own dynamics to perform specific tasks. Here we describe how small chemical networks that make use of enzymatic chemical reactions on the colloid surface can be used to construct motor-based chemical logic gates. Some basic features of coupled enzymatic reactions that are responsible for propulsion and underlie the construction and function of chemical gates are described using continuum theory and molecular simulation. Examples are given that show how colloids with specific chemical logic gates can perform simple sensing tasks. Due to the diverse functions of different enzyme gates, operating alone or in circuits, the work presented here supports the suggestion that synthetic motors using such gates could be designed to operate in an autonomous way in order to complete complicated tasks.

Ghaemi Mohammad Hossein, Sayenko Sergiy Y., Shkuropatenko Volodymyr et al.

Ionic substitutions play important role in the modifications of biological apatites. Recently, the attention has been focused on the co-doping effects on functional properties of apatite based biomaterials. In this research work, the dense samples of fluorapatites, Ca10(PO4)6F2 and Ca8MgSr(PO4)6F2, were produced after sintering at 1250°C for 6 h in air. Structural characterization, carried out with XRD, IR, Raman and SEM, confirmed the formation of dense and homogeneous structure with main fluorapatite and small amount of Ca3(PO4)2 phase. The presented results also demonstrate the stability of structural and mechanical properties of fluorapatites after immersion tests in saline and buffer solutions. The durability of mechanical properties and biocompatibility of the Ca10(PO4)6F2 and Ca8MgSr(PO4)6F2 fluorapatites make these materials highly attractive for biomedical application.

Vratislav Psota, Olga Dvořáčková, Markéta Musilová

Ten new varieties of malting barley were registered in the Czech Republic after the 2021 harvest. After four years of testing, the malting barley varieties Fangio and LG Slovan were registered, and after three years of testing, the spring barley varieties Evgenia, Guzel, LG Flamenco, LG Lodestar, LG Sedlak, Schiwago, SY Solar and the winter barley variety Suez were registered. Based on the results obtained, LG Slovan and LG Sedlak were recommended for the production of beer with the protected geographical indication 'České pivo'. These varieties showed low activity of proteolytic and cytolytic enzymes and low level of final attenuation. The other spring barley varieties (Evgenia, Fangio, Guzel, LG Flamenco, LG Lodestar, Schiwago and SY Solar) gave wort with extract contents ranging from 82.5 to 83.6 %, with Guzel, Evgenia, Fangio and Schiwago showing extract contents above 83 %. Proteolytic modification was mostly at an optimal level in these varieties, with only Fangio, Schwago and Guzel having the Kolbach index above 50 %. The β-glucan content in wort below 50 mg/l was recorded for Schiwago and Fangio. The level of final attenuation for these varieties ranged from 80.7 % to 82.8 %, while final attenuation level above 82.5 % was observed for the varieties Fangio and Guzel. LG Lodestar and SY Solar always produced clear wort. Low to zero lipoxygenase enzyme activity was found in LG Lodestar. The winter barley variety Suez gave malt with an average extract content of 81.9 %. Proteolytic modification, cell wall degradation and malt quality were at an optimal level. The β-glucan content was 158 mg/l.

Bao-Hong Lee, Kung-Ting Hsu, You-Zuo Chen et al.

Flower thinning is often used during the planting of fruit trees to improve fruit quality and promote large fruit. Flower buds become an agricultural by-product of the planting process. Pitaya (<i>Hylocereus undatus</i>) is a popular fruit in many tropical regions, which is widely cultivated in Southeast Asian countries. Probiotics such as <i>Lactobacillus plantarum</i> have been shown to exhibit an anti-obesity effect by regulating gut microbiota. This study investigated the effect of polysaccharides from pitaya flower buds (PFW) extracted with water on the regulation of gut microbiota and body weight control in mice fed with a high-fat diet. The effects of PFW on the growth of <i>L. plantarum</i> were analyzed and the propagation of <i>L. plantarum</i> was promoted in an aqueous solution containing PFW. In an in vivo study, mice were fed with a high-fat diet supplemented with PFW for 12 weeks; PFW treatment effectively controlled body weight and reduced short bowel syndrome of mice induced by the high-fat diet. Gut microbiota sequencing revealed that Lachnospiraceae and Lactobacillaceae were the main bacteria targeted by PFW. Moreover, transcript analysis demonstrated that PFW alleviated obesity through amino acid metabolism, carbohydrate metabolism, and glycan metabolism. Overall, PFW is a valuable food supplement that can regulate gut microbiota and may have potential to ameliorate the physiological damage caused by a high-fat diet.

Maw Ni Soe Htet, Honglu Wang, Lixin Tian et al.

Sorghum has good adaptation to drought tolerance and can be successfully cultivated on marginal lands with low input cost. Starch is used in many foods and nonfood industrial applications and as a renewable energy resource. Sorghum starches with different amylose contents affect the different physicochemical properties. In this study, we isolated starches from six sorghum varieties (i.e., Jinza 34, Liaoza 19, Jinnuo 3, Jiza 127, Jiniang 2, and Jiaxian) and investigated them in terms of their chemical compositions and physicochemical properties. All the starch granules had regular polygonal round shapes and showed the characteristic “Maltese cross”. These six sorghum starches showed an A-type diffraction pattern. The highest amylose content of starch in Jinza 127 was 26.90%. Jiaxian had a higher water solubility at 30, 70, and 90 °C. From the flow cytometry analysis based on six sorghum starch granules, Liaoza 19 had a larger and more complex granules (particle percentage (P1) = 66.5%). The Jinza 34 starch had higher peak (4994.00 mPa∙s) and breakdown viscosity (4013.50 mPa∙s) and lower trough viscosity (973.50 mPa∙s). Jinnuo 3 had higher onset temperature, peak temperature, conclusion temperature, gelatinization enthalpy, and gelatinization range. The principal component analysis and hierarchical cluster analysis based on classification of different sorghum starches showed that Jiniang 2 and Jinnuo 3 had similar physicochemical properties and most divergent starches, respectively. Our result provides useful information not only on the use of sorghum starches in food and non-food industries but for the great potential of sorghum-based intercropping systems in maintaining agricultural sustainability.

Shweta Suri, Anupama Singh, Prabhat K. Nema et al.

Kinnow mandarin (<i>Citrus reticulate</i> L.) peels are a storehouse of well-known bioactive compounds, viz., polyphenols, flavonoids, carotenoids, limonoids, and tocopherol, which exhibit an effective antioxidant capacity. However, naringin is the most predominant bitter flavanone compound found in Kinnow peels that causes their bitterness. It prohibits the effective utilization of peels in food-based products. In the present study, a novel approach for the debittering of Kinnow peels has been established to tackle this problem. A comparative evaluation of the different debittering methods (chemical, microbial, and ultrasound-assisted microbial treatments) used on Kinnow peel naringin and bioactive compounds was conducted. Among the chemical and microbial method; solid-state fermentation with A. niger led to greater extraction of naringin content (7.08 mg/g) from kinnow peels. Moreover, the numerical process optimization of ultrasound-assisted microbial debittering was performed by the Box–Behnken design (BBD) of a response surface methodology to maximize naringin hydrolysis. Among all three debittering methods, ultrasound-assisted microbial debittering led to a greater hydrolysis of naringin content and reduced processing time. The optimum conditions were ultrasound temperature (40 °C), time (30 min), and <i>A. niger</i> koji extract (1.45%) for the maximum extraction rate of naringin (11.91 mg/g). These debittered Kinnow peels can be utilized as raw material to develop therapeutic food products having a high phytochemical composition without any off-flavors or bitterness.

Alexander F. Sax

Chemical bonding is the stabilization of a composite molecular system caused by different interactions in and between the subsystems, among the strong kinds of bonding is covalent bonding especially important. Characteristic for covalent bonding are small atom groups with short distances between the involved atoms, indicating that covalent bonding is essentially a local effect, according to Lewis, this is caused by shared electron pairs. However, the energetic stabilization is an approximately additive one-electron effect, as was shown by Ruedenberg and coworkers. In systems composed of many-electron subsystems, the fermionic character of the electrons determines the structure of the electron distribution in a subsystem, and it is decisive for the local interactions between the subsystems. Especially important is the Pauli exclusion principle (PEP), which directs the relative positions of identical electrons. Spin and charge rearrangements are of utmost importance for chemical bonding. Quantum chemical methods like CASSCF (complete active space SCF), also called FORS (fully optimized reaction space), are made to cover all such processes. The standard building blocks of CASSCF wave functions are delocalized molecular orbitals, which cannot display local effects. OVB (orthogonal valence bond) is a method to analyze CASSCF wave functions and to reveal local processes that are responsible for both the energetic aspects of bonding and the spatial structure of the stabilized system. This is shown by analyzing dissociation of ethene, disilene, and silaethene, and the corresponding reverse reactions. Aspects of diabaticity of the reactions and entanglement of subsystems are discussed.

Tetsuya J. Kobayashi, Dimitri Loutchko, Atsushi Kamimura et al.

We derive the Hessian geometric structure of nonequilibrium chemical reaction networks (CRN) on the flux and force spaces induced by the Legendre duality of convex dissipation functions and characterize their dynamics as a generalized flow. With this structure, we can extend theories of nonequilibrium systems with quadratic dissipation functions to more general ones with nonquadratic ones, which are pivotal for studying chemical reaction networks. By applying generalized notions of orthogonality in Hessian geometry to chemical reaction networks, we obtain two generalized decompositions of the entropy production rate, each of which captures gradient-flow and minimum-dissipation aspects in nonequilibrium dynamics.