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The use of self-inducible promoters is a promising strategy to address metabolic imbalances caused by overexpression. However, the low activity of natural self-inducible promoters hinders their widespread application. To overcome this limitation, we selected the fic promoter as a model promoter to create an enhanced self-inducible promoter library using saturation mutations and high-throughput screening. Sequence analysis revealed that these promoters share certain characteristics, including semi-conservation in the −35 hexamer, highly conserved cytosine in the −17 motif (compared to −13 for other promoters), and moderate A+T content between positions −33 and −18 in the spacer region. Additionally, the discriminator region of these promotors features high A+T content in the first five bases. We identified PficI-17, PficII-33, and PficIII-14 promoters as the optional promoters in the −35 hexamer, spacer region, and discriminator mutation libraries, respectively. These promotors were used as representatives to measure the specific fluorescence and OD600 nm dynamics in different media and to confirm their effect on the expression of different proteins, including egfp (enhanced green fluorescence protein) and rfp (red fluorescence protein). Overall, our findings provide valuable guidance for modifying promoters and developing a promoter library suitable for regulating target genes.

An integrated laboratory experiment was designed for introducing biochemistry students to basic static biochemistry to deepen their understanding on the properties and analysis of biomolecules such as total carbohydrates, lipid, protein, and protein-constituent amino acids. Food represents a very important source of biomolecules of technological and functional interest; therefore, 15 types of food samples were selected to demonstrate the analysis of basic composition of these biomolecules. In this experiment, students learnt testing the total carbohydrates of all the food samples using 3,5-dinitrosalicylic acid (DNS) method, while performing acid hydrolysis. Then, lipid extraction was done using Soxhlet extraction method in order to determine the crude lipid concentration in different samples. After this, the students learnt testing crude protein content of these samples by using Kjeldahl method, and amino acid analysis was performed using HPLC. From the experiments, students grasped the concept and advantages of these methods and deepened their understanding on compositional analysis of different food samples. This laboratory exercise can be included into any college-level biochemistry courses and gives hands-on experience to the students for conducting scientific research in the field of life sciences, food science, and other bio-related fields.

Thermophilic endoglucanases have become of significant interest for effectively catalyzing the hydrolysis of cellulose. Myceliophthora thermophila is an ideal source of thermophilic enzymes. Interestingly, different hosts differently express the same enzymes. In this study, we successfully overexpressed endoglucanase (MtEG5-1) from M. thermophila in the methylotrophic yeast, Pichia pastoris GS115, via electroporation. We found that purified MtEG5-1 exhibited optimum activity levels at pH 5 and 70 °C, with 88% thermal stability after being incubated at 70 °C for 2 h. However, we observed that purified MtEG5-1 had a molecular weight of 55 kDa. The Km and Vmax values of purified MtEG5-1 were approximately 6.11 mg/mL and 91.74 μmol/min/mg at 70 °C (pH 5.0), respectively. Additionally, the optimum NaCl concentration of purified MtEG5-1 was found to be 6 g/L. Furthermore, we observed that the activity of purified MtEG5-1 was significantly enhanced by Mn2+ and was inhibited by K+. These results indicated that MtEG5-1 expressed by P. pastoris GS115 is more heat-tolerant than that expressed by A. niger and P. pastoris X33. These properties of MtEG5-1 make it highly suitable for future academic research and industrial applications.

Paper wastes form the major biodegradable fraction of the municipal solid waste. One of the best ways to treat paper wastes is using them as a feedstock for biomethane production through anaerobic digestion (AD). However, the AD characteristics, kinetics, and energy potential of different types of paper wastes are not clear. In this study, four kinds of typical paper wastes including corrugated board (CB), office paper (OP), tissue paper (TP), and magazine paper (MP) were used as feedstocks to produce biomethane at different volatile solids (VS) organic loading (OL). TP had a high cellulose content and showed high biomethane potential, while the lowest was obtained by CB, possibly due to its high lignin content. Kinetic analysis showed that Cone and modified Gompertz model could fit the biomethane production process well. Energy potential analysis revealed that biomethane yield, electric generating efficiency, and electricity price were the principal factors accounting for the profitability of biomethane production project treating paper wastes. Overall, paper wastes could be a promising feedstock for biomethane production, because paper wastes not only had high biomethane yield and biodegradability that exceeded many kinds of organic wastes but also could be continuously supplied for AD plants without the influence of seasonal changes.

Glycoprotein imprinted polymers have rapidly grown as excellent receptors for cancer targeting, diagnostics, inhibition, and nanomedicines as they specifically target glycans and glycosites overexpressed in various tumors. Compared to natural antibodies, they are easy to synthesize, stable, and cost-efficient. Currently, no study specifically discusses glycoproteins imprinting strategies for cancer theranostics. In this review, firstly we explored various factors involved in designing and synthesis of glycoprotein imprinted materials, including, the characteristics and choice of monomers for imprinting, types of templates and their interactions involved, and the imprinting methods. Secondly, the integration of these MIPs with different probes that have been applied for

Anaerobic digestion (AD) is one of the most promising technologies for treating municipal solid waste (MSW) to produce clean energy in the form of biogas. Although AD has been efficiently employed in developed countries, however, its application in the developing countries is still far from enough. This paper for the first time identifies the detailed prospects of the development of the AD industry in China by applying the political, economic, social, and technical framework followed by an in-depth cost–benefit analysis which can be used as a case for other developing countries. The findings of this study revealed that incentive policies such as feed-in tariffs (FIT), credits for carbon reduction and tax exemptions ensure progress in AD application on a large scale. Furthermore, MSW treatment capacity using harmless treatment facilities including anaerobic digestion will rise from 21.6 thousand tons per day in 2015 to 36.4 thousand tons per day by 2020 in China. Moreover, the social capitals have been stimulated by the higher investments from the government for the development of the AD industry. AD plants have low cost of operation due to their smaller sizes, water saving capacity and higher digestion efficiencies, which makes anaerobic digestion a competitive alternative for the treatment of MSW in the near future. The cost–benefit analysis revealed that AD projects have good market potential with an attractive net profit margin and an internal rate of return (IRR) of 31% and 12%, respectively. The industry has enormous potential for attracting foreign investment, while generating considerable revenue. The information provided in this study is helpful to advance the implementation of AD systems in China and other developing countries.

Demand Side Management (DSM) performs a significant function in the electrically powered energy system in order to manage power demand-side resources. Although China has brought DSM for the first time in the early 1990s, its advantages have not been entirely utilized. In this study, we first present a quick history of the energy policy of China, its electricity enterprise, and reform. Based on the analysis of DSM practices in Asia- Pacific region, the DSM development and the reform of electrical energy pricing in seven countries namely, Pakistan, India, Malaysia, Singapore, Thailand, Bangladesh, and China have been discussed. The primary limitations to DSM include fallacious market-oriented DSM mechanisms, the underdeveloped power carrier industry, low motivation level of grid companies for DSM because of their conventional business model, and low motivation of electricity end-users. This paper represents a case study of China’s electricity sector reform which can probably alter power transmission and pricing of distribution scheme and enterprise model of grid companies, thereby enhancing competition. A number of rules & regulations and series of policies linked to DSM were formulated by Chinese country wide ministries. But still, there are many troubles in the implementation of DSM. The current status of DSM improvement in China is investigated from distinct factors of policies and guidelines associated with DSM, DSM improvement of representative regions and DSM organizational administration. This study has also discussed the challenges faced by the implementation of DSM and proposed feasible measures totally based on the challenges encountered in implementing of DSM. This study is beneficial in promoting the improvement of China’s DSM. Based on these findings, the possible effects of DSM reforms are; government must give more attention to DSM; grid companies might also have better incentives to invest in DSM; DSM end users of electricity motivations may also increase; demand response applications can be improved and commercial DSM business models can be proposed.

Anaerobic digestion (AD) is a promising technology for treating food waste, as it has high energy recovery and controls environmental problems. The biogasification performance of food waste was observed by changing the process parameters such as hydraulic retention time (HRT) and organic loading rate (OLR). A continuously stirred tank reactor (CSTR) was operated to investigate one-phase anaerobic digestion performance of food waste due to its easy operation and lower cost for industrial application. Two operating conditions R1 (fixed HRT and loading) and R2 (varying HRT and loading concentration) were set for 116 and 92 days respectively. Results showed that the best OLR for R1 was 2.25 g ⋅ L−1 ⋅ d−1 with the biogas yield of 787 mL ⋅ g−1 ⋅ d−1. However, the best OLR for R2 was also 2.25 g ⋅ L−1 ⋅ d−1 with the biogas yield of 724 mL ⋅ g−1 ⋅ d−1. Reactor 1 with fixed HRT showed better performance with higher biogas yield and better stability indicators. The results obtained in this study would be useful for industrial utilization of food waste in the future.

A large amount of sheep dung (SD) produced on farms in China is a potential feedstock for production of clean energy in the form of biogas. Similarly, waste paper can be a notable energy source that is worth exploiting. In this study, we assessed the feasibility of co-digesting nitrogen-rich SD with the carbon-rich corrugated board (CB) or waste office paper (OP) in varying volatile solids (VS) ratios, to produce methane. Synergistic effect of co-digesting SD with CB and SD with OP on methane production was found in this study. The highest methane yields of 151.62 and 198.85 mL/g-VS were obtained during the co-digestions of SD with CB at 4:1 ratio (SDCB) and SD with OP at 2:3 ratio (SDOP), respectively. High-throughput 16 S rRNA gene sequencing demonstrated that the microbial diversity and richness in SDCB and SDOP co-digests were higher than in SD and OP mono-digests, respectively. Characteristic bacteria and archaea in the digests were strongly substrate-related and might contribute to methane production. The validated results indicated that methane production through anaerobic co-digestion of SD and waste paper can be an efficient way that could not only reduce environmental pollution but also contribute to methane production.

China has attracted many international students in the past five years through Chinese Scholarship Council (CSC) to improve the standard of higher education and research productivity. Most of the students come from “One belt, One Road” countries to pursue master and doctoral degrees. The School of International Education and Graduate School at Beijing University of Chemical Technology (BUCT), China implemented Advanced Academic Writing Skills (AAWS) as a mandatory course for non-native English-speaking students, belonging to One Belt, One Road (OBOR), to enable them to improve and polish their academic writing skills. The ultimate goal of this paper is to critically investigate student’s perception of the AAWS mandatory course to improve their academic writing skills. Formative and summative assessments and student perceptions were used to assess the student satisfaction and knowledge. An evaluation index was administered to collect student perceptions about the course. Students reported a high degree of satisfaction with the course, indicating that the course was well-designed and implemented. The results provided a model to other universities to bring adjustments for the improvement of the academic writing skills of young researchers, and comprehensively improve the quality of research and publications worldwide.  https://doi.org/10.26803/ijlter.16.10.7

This study employs a microaerobic pretreatment that includes different microbial reagents combined with oxygen to enhance the energy conversion potential of rice straw (RS) via anaerobic digestion (AD) in a more cost-effective and time-efficient manner. Five broad varieties of microbial reagents including liquid consortium (LC), cow manure (CM), sheep dung (SD), biogas slurry (BS), and straw-decomposing consortia (SC), have been used as sources of useful microbes at varying oxygen concentrations of 0, 6, 12 and 24 mLO2/gVS to explore the effect of microaerobic pretreatment on RS degradation. The results showed that RS pretreated with SC had the highest cumulative methane yield (CMY) of 311.7 mL/gVS at 12 mLO2/gVS, followed by BS, CM, LC, and SD, with the CMYs of 270.5, 263.2, 257.1, and 256.7 mL/gVS at 6 mLO2/gVS, respectively. The RS pretreated with SC, BS, CM, LC, and SD led to improvements in the methane yield by 88.7%, 63.7%, 59.3%, 55.6%, and 55.4%, respectively, compared to the untreated RS. The microbial community analysis revealed that the relative abundance (RA) of Firmicutes, which are known to play a key role in accelerating the rate of hydrolysis, increased after microbial pretreatment combined with oxygen supply. The RA of Clostridium III, which facilitates cell wall degradation via hydrolytic pathways along with other sugar-fermenting bacteria, such as Saccharofermentans, Lutaonella, and Sedimentibacter, increased after AD in the digestate of pretreated RS compared to that in untreated RS. Moreover, a shift in acetoclastic and hydrogenotrophic archaea, including Methanothrix and Methanospirillum, was also observed, indicating precursor changes resulted by pretreatments and varied microbial metabolism, which might have enhanced the methane production process of RS. The energy potential analysis revealed that microbial pretreatment was a suitable technique for stimulating the energy conversion efficiency of RS. This study can be used as a reference for future utilization of a diverse range of lignocellulosic materials for clean energy production.

Anaerobic digestion (AD) is a widely applied technology for treating organic wastes to generate renewable energy in the form of biogas. The effectiveness of AD process depends on many factors, among which the most important is the presence of active and healthy microbial community in the anaerobic digesters, which needs to be explored. However, the deciphering of microbial populations and their functions during the AD process of different materials is still incomplete, which restricts the understanding of its long-term performance under different operational conditions. This review describes the type, morphology, functions, and specific growth conditions of commonly found hydrolytic, acidogenic, acetogenic bacteria, and archaea during the AD process. The effects of microbes on the performance and stability of the digestion process are also presented. Furthermore, the article offers a deep understanding of the AD management strategies for the enhancement of methane production and the efficiency of the energy conversion process of various organic wastes.

Biochar simply is the material produced when biomass undergoes any chemical processes under the conditions of pyrolysis. The variety of biomasses, including wood waste, agricultural crop leftover, organic waste, animal manure, and forestry residues, have been considered as raw material to produce biochar. Biochar is widely used for generation of heat and power and an addition to soils, in which it serves as a fertilizer and carbon sequestration agent. Also in the form of being activated, it finds significant role for various adsorption applications. The most beneficial use of a given char depends on its physical and chemical characteristics, even though the relationship of char properties to these applications is not well defined. Various widely used modern analytical techniques, which are applicable and crucial for biochar characterization, have been reviewed in the present work, such as solid state nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, X-rays photoelectron spectroscopy, X-rays diffraction, thermogravimetric analysis, near edge X-rays absorption fine structure spectroscopy, and gas chromatography-mass spectroscopy. Utilization of these modern techniques provides the quantitative as well as qualitative information, i.e., determining the sizes, shapes, and physicochemical characteristics of biochar, which is reliable to track changes in the carbon arrangement over reaction time and temperature, and will be useful for efficient production of biochar and application. It provides the useful information for the researchers in this area and is beneficial not only for the effective biochar production, but also for potential utilization/application, and not only for environment but also for agriculture.

Engineering representing the backbone of a nation aims to migrate towards the knowledge economy. The strengthening of engineering education leads to the nation’s self-reliance while building indigenous capabilities. The current study attempts to compare engineering education in China with Pakistan, Europe, and the USA in context of One Belt, One Road (OBOR) initiative. The comparison provided by this study will help to identify some of the trends and challenges in engineering education at the national and regional level of OBOR countries. The study suggests that OBOR strategy will allow China to build excellence in engineering education and export its expertiseamong the member countries during developing stage.

Agricultural residues, such as lignocellulosic materials (LM), are the most attractive renewable bioenergy sources and are abundantly found in nature. Anaerobic digestion has been extensively studied for the effective utilization of LM for biogas production. Experimental investigation of physiochemical changes that occur during pretreatment is needed for developing mechanistic and effective models that can be employed for the rational design of pretreatment processes. Various-cutting edge pretreatment technologies (physical, chemical and biological) are being tested on the pilot scale. These different pretreatment methods are widely described in this paper, among them, microaerobic pretreatment (MP) has gained attention as a potential pretreatment method for the degradation of LM, which just requires a limited amount of oxygen (or air) supplied directly during the pretreatment step. MP involves microbial communities under mild conditions (temperature and pressure), uses fewer enzymes and less energy for methane production, and is probably the most promising and environmentally friendly technique in the long run. Moreover, it is technically and economically feasible to use microorganisms instead of expensive chemicals, biological enzymes or mechanical equipment. The information provided in this paper, will endow readers with the background knowledge necessary for finding a promising solution to methane production.