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To simplify purification and improve heat tolerance of a thermostable β-xylosidase (ThXylC), a short ELK16 peptide was attached to its C-terminus, which is designated as ThXylC–ELK. Wild-type ThXylC was normally expressed in soluble form. However, ThXylC–ELK assembled into aggregates with 98.6% of total β-xylosidase activity. After simple centrifugation and buffer washing, the ThXylC–ELK particles were collected with 92.57% activity recovery and 95% purity, respectively. Meanwhile, the wild-type ThXylC recovery yield was less than 55% after heat inactivation, affinity and desalting chromatography followed by HRV 3C protease cleavage purification. Catalytic efficiency (Kcat/Km) was increased from 21.31 mM–1s–1for ThXylC to 32.19 mM–1s–1for ThXylC–ELK accompanied by a small increase in Kmvalue. Heat tolerance of ThXylC–ELK at high temperatures was also increased. The ELK16 peptide attachment resulted in 6.2-fold increase of half-life at 65 °C. Released reducing sugars were raised 1.3-fold during sugar cane bagasse hydrolysis when ThXylC–ELK was supplemented into the combination of XynAΔSLH and Cellic CTec2.

The review presents the recent trends in green and sustainable chemistry, as well as waste valorization and their applicability to understand and realize the concept of a circular economy. It also provides a comprehensive global perspective of the linear plastics economy and makes the case for its transformation into a circular plastics economy. Furthermore, bioconversion in a food waste biorefinery to produce fructose as an example of a high value-added product is given as a case study to demonstrate the feasibility of a circular economy.

Textile waste is a growing concern globally. While the most efficient solution is to prevent waste generation, the valorisation of textile waste streams into value-added products is imperative to divert textile products away from saturated landfills at their end. Rapid innovation in various valorisation technologies to deal with the large variety of natural and synthetic textiles and their blends, such as cotton-polyester, is promising. However, it is critical to benchmark and compare these emerging technologies before scale-up to ensure a good fit for the local circular economy. In this opinion piece, we stress the application of life cycle assessment and related approaches for systematic evaluation of the environmental, social, and economic implications to steer the selection of appropriate textile waste valorisation pathways based on the nature of the waste stream and the demand for the valorised product in the local economy.

Food waste that is disposed of or not processed tends to release greenhouse gases, such as carbon monoxide, methane, and carbon dioxide, into the atmosphere. Therefore, it is necessary to explore food waste management techniques and the conversion of food waste into value-added products. With a focus on lipase and bacterial cellulose production, this paper first demonstrates the functions of several bioprocesses in the transformation of food waste. It also elucidates the bioconversion of food waste into value-added products such as polyurethane foam and personal protective equipment. State-of-the-art multiomics strategies for managing food waste in the context of pollution control and the movement towards a circular bioeconomy are discussed, and potential roadblocks are identified.

A beam loss monitoring system is being designed for PEFP(Proton Engineering Frontier Project) by Korea Atomic Energy Research Institute(KAERI). The beam loss monitoring system is based on the ion chamber and an electrometer. An air-filled ion chamber was designed and fabricated as a prototype detector of beam loss monitor. The radiation response of the ion chamber was simulated by using EGSnrc code. The collection efficiency and stability of the ion chamber with respect to the different radii of inner electrodes is discussed. The proper choice of high voltage bias polarity for the ion chamber is also studied. The test of the ion chamber under high dose rate is under way at KAERI gamma irradiation facility at the exposure rate of 106R/h.