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Smart materials possess a high potential for application in process engineering. Among these smart materials, stimuli-responsive hydrogels exhibit the chemically inherent characteristic to signific...

In this work, the potential of lignin as a filler additive and anti-aging agent in a pressure-sensitive adhesive (PSA) based on natural rubber (NR) was investigated. Herein, different approaches to incorporate lignin into NR matrix by adaptation of a two-step compounding process were evaluated. At first, a twin-screw extruder (TSE) was utilized to prepare pre-formulations followed by the secondary finalization of adhesive mass inside a planetary roll extruder (PRE). For the industrial production of PSAs, the adhesive mass is required to have well-distributed additive materials and adequate adhesion, cohesion, and longevity. The impact of the added lignin was evaluated concerning optical appearance, compatibility between lignin and rubber/resin, adhesion performance, shear strength, thermal stability, antioxidant capability, dynamic-mechanical behavior, aging behavior at elevated temperature and under UV exposure, and filler morphology. It was found that the PSAs including aquasolv (AS) lignin after the spray-drying post-treatment exhibited excellent thermal, mechanical, and antioxidative properties. Thus, it was shown that the sustainably producible lignin can be utilized both as filler and antioxidant in natural rubber-based pressure-sensitive adhesive masses with comparable performance properties as commercially available products.

Natural compounds include a boundless diversity of molecules and functionalities that represent an excellent pool of materials for production of functional foods, food additives, and pharmaceuticals. Research on lignin functional and bioactive properties has recently become the center of interest for research centers worldwide, chasing for the complete valorization of products obtained in biorefining processes and unraveling the potential of this natural polymer for its use in high adding-value target industries, as the case of pharmaceutical, food, and cosmetics. This review addresses the potential applications of lignin for human consumption products, as well as the current challenges that these potential products need to overcome in the regulatory frame and consumer acceptance. Moreover, lignin structure-related mechanisms are proposed with emphasis in pharmaceutical and food applications.

BACKGROUND Ginsenoside Rb1 is one of the major bioactive components of Panax ginseng C.A. Meyer (Araliaceae), a medicinal plant that has been used for therapeutic purposes for thousands of years in Asian countries. The pharmaceutical activity of ginsenoside Rb1 highly depends on molecular structure and its deglycosylated metabolites are known to be more potent bioactive compounds. However, these deglycosylated ginsenosides do not exist naturally so they are usually obtained by poorly selective methods, like chemical hydrolysis. RESULTS In this study, the development and characterization of an alginate-based immobilized enzyme microreactor for the catalytic conversion of ginsenoside Rb1 to more bioactive metabolites have been reported. Enzyme kinetic parameters were calculated and characterization tests (such as determination of surface area of alginate matrix, long-term use, and effect of residence time on conversion yield) were conducted. The system was operated under continuous-flow conditions and compared with acidic and batch enzymatic hydrolysis experiments, as conventional approaches. The enzymatic microreactor showed an enhanced activity by producing 13-fold higher amount of ginsenoside F2 than batch enzymatic hydrolysis. CONCLUSION Obtained results indicated that the newly developed enzymatic microreactor could successfully convert ginsenoside Rb1 to more active metabolites and have a potential for the biocatalysis of multiple ginsenosides, as well as pharmaceutically active compounds. (c) 2021 Society of Chemical Industry (SCI)., Scientific and Technological Research Council of Turkey (TUBITAK) [:113M050, 2211-C]; Federal Ministry of Education and Research (BMBF) [01DL14002], This work was supported by the Scientific and Technological Research Council of Turkey (TUBITAK, grant numbers:113M050 and 2211-C) and the Federal Ministry of Education and Research (BMBF, grant number 01DL14002).

Tourism is the leading industry of island cities and the tourism carrying capacity is of great significance to the sustainable development of cities. This paper adopts the state-space model to construct an early warning indicator system for tourism carrying capacity from three aspects: nature, economy, and society, explores the early warning status, and spatial and temporal differences of tourism carrying capacity in Chinese island cities, and makes use of the BP(Back Propagation) neural network model to predict the development trend of early warnings. The results show that (1) from 2012 to 2018, the early warning status of China&rsquo, s island cities&rsquo, tourism carrying capacity is generally on the rise, the natural carrying capacity system&rsquo, s early warning situation has deteriorated, which is in a state of severe warning interval. The economic carrying capacity and social carrying capacity are on the rise, and the warning degree is from the super warning interval to the severe warning interval and then to the moderate warning degree. The forecast of the overall tourism carrying capacity early warning index from 2019 to 2021 presents an upward trend and is in the moderate warning interval. (2) The tourism carrying capacity early warning in China&rsquo, s island cities shows a large spatial and temporal difference and the early warning values of each island city are different. The early warning value of Putuo tourism carrying capacity always ranks first, and Changdao has the worst performance. (3) In accordance with the contribution status of the subsystem to the total system, the Chinese island cities show regional differences in the northern, central, and southern area, showing two forms of pressure cities and pressure-carrying cities. The government can adopt different policies and measures in accordance with different characteristics of human environmental activities.

Reactive distillation is one of the most well-established integrative separation processes in chemical industry which is used for the production of e.g. fuel additives. Recently, the feasibility of enzymes in reactive distillation columns was demonstrated, which possibly extends the scope towards more selective reactions with chiral products. However, the low thermal stability of enzymes necessitates a more frequent catalyst exchange which is usually a knock-out criterion for this process due to very high costs of catalytic structures and long process shut down times. In this work, an in situ production method for biocatalytic coatings on structured packings is presented which enables production and renewal of the catalytic structures in place, i.e. without disassembly of the column internals. By flooding the column with reacting enzyme/silica-sol, gauze structured packings are covered with a uniform layer of gel, which after drying results in a catalytic coating containing immobilized enzymes. The in situ method could help simplify the catalyst exchange in reactive distillation processes and furthermore allows changes in the reactive section in terms of amount and position of the catalyst which are important process parameters in the design phase of reactive distillation processes. Video: For a video showing the in situ procedure, please see Supplementary data .

Reactor design and development are key disciplines in process engineering. In order to keep up with modern-day production demands, new reactor concepts have to be conceived, which transcend the mere purpose of a reaction vessel. With the availability of improved fabrication methods and insight into new materials, novel process integration measures and process-adapted setups can be developed to provide a new generation of reactors. The application of smart materials allows for response-triggered actuation, which can be used in setups for self-contained process control without external input. In combination with available 3D fabrication technologies, smart materials can be integrated and adapted to the reaction system demands, to develop smart reactor concepts. Herein, we demonstrate an exemplary application of a smart reactor module for an exothermic emulsion copolymerization of vinyl acetate (VAc) and Versa® 10, a vinyl neodecanoate. The flow manipulation of the reaction medium on a preparative scale is presented by using poly(N-iso-propylacrylamide) (pNIPAM) hydrogels as temperature-triggered actuators, which are able to distinguish the course of the reaction by separating the flow of reactant from product stream during continuous operation.

DOC-1R (deleted in oral cancer-1 related) is a novel putative tumor suppressor. This study investigated DOC-1R antitumor activity and the underlying molecular mechanisms. Cell phenotypes were assessed using flow cytometry, BrdU incorporation and CDK2 kinase assays in DOC-1R overexpressing HeLa cells. In addition, RT-PCR and Western blot assays were used to detect underlying molecular changes in these cells. The interaction between DOC-1R and CDK2 proteins was assayed by GST pull-down and immunoprecipitation-Western blot assays. The data showed that DOC-1R overexpression inhibited G1/S phase transition, DNA replication and suppressed CDK2 activity. Molecularly, DOC-1R inhibited CDK2 expression at the mRNA and protein levels, and there were decreased levels of G1-phase cyclins (cyclin D1 and E) and elevated levels of p21, p27, and p53 proteins. Meanwhile, DOC-1R associated with CDK2 and inhibited CDK2 activation by obstructing its association with cyclin E and A. In conclusion, the antitumor effects of DOC-1R may be mediated by negatively regulating G1 phase progression and G1/S transition through inhibiting CDK2 expression and activation.