Abstract:从本期开始，本刊主编或副主编将遴选1-2篇亮点文章进行点评，并对在生物工程领域具有重要应用价值的当期文章进行导读。主编导读不同于文章的摘要，主要侧重于用比较浅显的语言介绍文章的背景、主要思路和下一步的方向，旨在激发生物工程领域不同背景的读者对相关文章的阅读兴趣。主编导读也将在《生物工程学报》微信公众号同步刊发

Abstract:Exoelectrogenic microorganisms are the research basis of microbial electrochemical technologies such as microbial fuel cells, electrolytic cells and electrosynthesis. However, their applications are restricted in organic degradation, power generation, seawater desalination, bioremediation, and biosensors due to the weak ability of biofilm formation and the low extracellular electron transfer (EET) efficiency between exoelectrogenic microorganisms and electrode. Therefore, engineering optimization of interaction between exoelectrogenic microorganisms and electrode interface recently has been the research focus. In this article, we review the updated progress in strategies for enhancing microbe-electrode interactions based on microbial engineering modifications, with a focus on the applicability and limitations of these strategies. In addition, we also address research prospects of enhancing the interaction between electroactive cells and electrodes.

Abstract:In recent years, to solve the increasingly prominent problem of the contradiction between human social development and environmental resources, artificial meat has appeared in public view more and more. Generally speaking, the artificial meat can be divided into vegetable protein meat and cell cultured meat. Among them, vegetable protein meat has gradually begun to be commercialized, and cell cultured meat is cultured with animal cells, which is more similar to the real meat. Based on the analysis of the essence of cell cultured meat, we explore the positive significance of cell cultured meat technology for the meat production industry, consumer groups, and the sustainable development of mankind in the future. From the perspective of bioethics, the research, development and production of cell cultured meat can help ensure the sustainable development of human society, improve animal welfare, reduce resource demand, improve the nutritional function of meat products, and provide new growth points for the development of other industries. In addition, the ethical risks of food safety, technology abuse and technical supervision involved in cell cultured meat production are put forward for deep consideration, hoping to provide reference for the sustainable development of artificial meat industry from the perspective of bioethics.

Abstract:Polyhydroxyalkanoates (PHAs) are polymers obtained by esterification of hydroxy fatty acid monomers. Due to similar mechanical characteristics of traditional petroleum-based plastics, 100% biodegradability and biocompatibility, PHAs are considered to be one of the most potential green materials. However, the application and promotion of PHAs as a green and environmentally friendly material are difficult because of the high production costs. This article focuses on the current methods to reduce production cost of PHAs effectively, such as cell morphology regulation, metabolic pathway construction, economic carbon source utilization and open fermentation technology development. Despite most research results are still limited in laboratory, the research methods and directions provide theoretical guidance for the industrial production of economic PHAs.

Abstract:Breast cancer is the most common cancer in women. At present, the in vivo model and traditional cell culture are mainly used in breast cancer researches. However, as high as 90% clinical trials are failed for drugs explored by the above two methods, due to the inherent species differences between humans and animals, as well as the differences in the tissue structure between organs and cells. Therefore, organoid three-dimensional culture is emerging. As a new tumor research model, organoid, a three-dimensional cell complex with spatial structure, has broad application prospects, such as precision medicine, organ transplantation, establishment of refractory disease model, gene therapy and drug research and development. Therefore, organoid is considered as one of the ideal carriers for life science research in the future. Breast cancer, a heterogeneous disease with complex phenotypes, has a low survival rate. Breast cancer organoid can reproduce many key features of human breast cancer, thus, the construction of organoid biological library of breast cancer will provide a new platform for studying the occurrence, development, metastasis and drug resistance mechanism of breast cancer. In this review, we systematically introduce the culture conditions of organoids and their application in breast cancer related research, and the application prospect of organoids.

Abstract:Curcuminoids are rare diketone compounds in plants and can be found in the rhizome of Curcuma longa as well as other Zingiberaceae and Araceae. Curcuminoids have been widely used in food and medical area owing to the yellow colors, as well as the antioxidant and many other pharmacological activities. Curcuminoids are a mixture of compounds containing curcumin, demethoxycurcumin and bisdemethoxycurcumin, which have distinct benzene ring substituents. Currently, curcuminoids are exclusively produced through plant extraction, which do not satisfy the meeting of the market demand. Empowered with new synthetic biology tools and metabolic engineering strategies, there is renewed interest in production of curcuminoids using microorganisms. Heterologous production of curcuminoids has been achieved using Escherichia coli, Yarrowia lipolytica, Pseudomonas putida and Aspergillus oryzae via engineering of curcuminoids biosynthesis pathway. In this review, we first describe the biological activities and various applications of curcuminoids. Next, we summarize the biosynthetic pathway of curcuminoids in Curcuma longa and discuss the catalytic mechanisms of curcumin synthases. Then, we thoroughly explore recent advances in the use of distinct microorganisms for the production of curcuminoids with a special focus on metabolic engineering strategies. Finally, we prospect the microbial production of curcuminoids by highlighting some promising techniques and approaches.

Abstract:As an extremely important organelle in eukaryotic cells, endoplasmic reticulum (ER) plays a key role in the synthesis and processing of biomacromolecules, material transport, ion homeostasis maintenance, signal transduction, exchange of materials and signals between organelles. Many important human diseases, such as cancers, autoimmune diseases, pathogenic infections, neurodegenerative diseases and diabetes, are closely related to ER dysfunction. With the development of nanotechnology, the exploration and application of ER-targeted nanodrugs gradually become a research hotspot in the field of nanomedicine, bioengineering, material chemistry and other fields. In this paper, the relationship between ER dysfunction and disease occurrence, the principle of designing ER-targeted nanodrugs and their biomedical application are reviewed. ER-targeted nanodrugs are designed based on nanodrug carriers or self-assembly of bioactive molecules. These nanodrugs could target the ER in an active or passive manner and function by disrupting or maintaining the ER functions. The ER-targeting nanodrugs have a wide application prospect in cancer therapy, immune regulation, nervous system repairment, and so on.

Abstract:Higher alcohols are one of the main by-products of Saccharomyces cerevisiae in brewing. High concentration of higher alcohols in alcoholic beverages easily causes headache, thirst and other symptoms after drinking. It is also the main reason for chronic drunkenness and difficulty in sobering up after intoxication. The main objective of this review is to present an overview of the flavor characteristics and metabolic pathways of higher alcohols as well as the application of mutagenesis breeding techniques in the regulation of higher alcohol metabolism in S. cerevisiae. In particular, we review the application of metabolic engineering technology in genetic modification of amino transferase, α-keto acid metabolism, acetate metabolism and carbon-nitrogen metabolism. Moreover, key challenges and future perspectives of realizing optimization of higher alcohols metabolism are discussed. This review is intended to provide a comprehensive understanding of metabolic regulation system of higher alcohols in S. cerevisiae and to provide insights into the rational development of the excellent industrial S. cerevisiae strains producing higher alcohols.

Abstract:Resource utilization is an effective way to cope with the rapid increase of kitchen waste and excess sludge, and volatile fatty acids produced by anaerobic fermentation is an important way of recycling organic waste. However, the single substrate limits the efficient production of volatile fatty acids. In recent years, volatile fatty acids produced by anaerobic co-fermentation using different substrates has been widely studied and applied. In this paper, we analyze the characteristics of fermentation to produce acid using kitchen waste and excess sludge alone or mixture. Influences of environmental factors and microbial community structure on the type and yield of volatile fatty acids in the anaerobic fermentation system are discussed in detail. Moreover, we propose future research directions, to provide a reference for recycling kitchen waste and excess sludge.

Abstract:As a green and economic emerging technology, biological desulfurization is popular. However, biological desulfurization is inhibited by organosulfur in the treatment gases which cannot be ignored. This article summarizes relevant studies on the influence of organosulfur on biological desulfurization in recent years, including the types and physicochemical characteristics of organosulfur, the influence of organosulfur on the desulfurization process, the reaction mechanism of organosulfur, the interplay between organosulfur and some operating conditions, and species of microorganisms that are tolerant to organosulfur. Methods for mitigating the effect of organosulfur on the desulfurization process are discussed, to provide references for the stable and efficient operation of biological desulfurization.

Abstract:Lignocellulose is the most abundant renewable organic carbon resource on earth. However, due to its complex structure, it must undergo a series of pretreatment processes before it can be efficiently utilized by microorganisms. The pretreatment process inevitably generates typical inhibitors such as furan aldehydes that seriously hinder the growth of microorganisms and the subsequent fermentation process. It is an important research field for bio-refining to recognize and clarify the furan aldehydes metabolic pathway of microorganisms and further develop microbial strains with strong tolerance and transformation ability towards these inhibitors. This article reviews the sources of furan aldehyde inhibitors, the inhibition mechanism of furan aldehydes on microorganisms, the furan aldehydes degradation pathways in microorganisms, and particularly focuses on the research progress of using biotechnological strategies to degrade furan aldehyde inhibitors. The main technical methods include traditional adaptive evolution engineering and metabolic engineering, and the emerging microbial co-cultivation systems as well as functional materials assisted microorganisms to remove furan aldehydes.

Abstract:Laboratory evolution is an important approach to improve the performance of microorganisms. In the past decades, the methods for laboratory evolution have developed rapidly and applied widely. However, the commonly used evolution strategies for strains or specific proteins cannot achieve continuous mutation, and require multiple rounds of operation, therefore they are considered as a labor intensive process. The development of mutation and screening technologies have facilitated the development of continuous evolution in vivo and greatly improved the efficiency of laboratory evolution. The continuous in vivo evolution achieves in vivo mutation, perfectly combining mutation with screening to evolve a specific phenotype with minimal human intervention. This review summarizes the recent advances of in vivo continuous evolution technologies for either genome-scale mutation or evolution of specific proteins. The principles of these technologies and their applications are introduced. On this basis, the advantages and limitations of these technologies are discussed. We also give a perspective of future development of continuous in vivo evolution.

Abstract:Metabolic syndrome is a global chronic epidemic. Its pathogenesis is determined by genetic and environmental factors. Epigenetic modification is reported to regulate gene expression without altering its nucleotide sequences. In recent years, epigenetic modification is sensitively responded to environmental signals, further affecting the gene expression and signaling transduction. Among these regulators, chromatin remodeling SWI/SNF (SWItch/Sucrose non fermentable, SWI/SNF) complex subunit Baf60a plays an important role in maintaining energy homeostasis in mammals. In this paper, we described the pathophysiological roles of Baf60a in maintaining the balance of energy metabolism, including lipid metabolism, cholesterol metabolism, urea metabolism, as well as their rhythmicity. Therefore, in-depth understanding of Baf60a-orchestrated transcriptional network of energy metabolism will provide potential therapeutic targets and reliable theoretical supports for the treatment of metabolic syndrome.

Abstract:Bispeci?c antibody (BsAb) has two different antigen-binding sites, divided into the “IgG-like” format and the “non-IgG-like” format. Different formats have different characteristics and applications. BsAb has higher sensitivity and specificity than conventional antibodies, with special functions such as recruitment of immune cells and blocking of dual signaling pathways, playing an important role in immune-diagnosis and therapy. With the deterioration of the global environment and the irregular living habits of people, the incidence of tumor is becoming higher and higher. Tumor becomes the most serious fatal disease threatening human health after cardiovascular disease. There are 12 million estimated new tumor cases each year worldwide. The major clinical treatments of tumor are surgical resection, chemoradiotherapy, target therapy. Tumor immunotherapy is a novel approach for tumor treatment in recent years, and activates human immune system to control and kill tumor cells. Although the traditional monoclonal antibodies have already acquired some therapeutic effects in tumor targeted therapy and immunotherapy, they induce drug resistance resulted from the heterogeneity and plasticity of tumors. Binding to two target antigens at the same time, BsAb has been used in the clinical treatment of tumors and obtained promising outcomes. This review elaborates the research progress and applications of bispecific antibody in clinical tumor therapy.

Abstract:One-carbon compounds such as methanol and methane are cheap and readily available feedstocks for biomanufacturing. Oxidation of methanol to formaldehyde catalyzed by methanol dehydrogenase (MDH) is a key step of microbial one-carbon metabolism. A variety of MDHs that depend on different co-factors and possess different enzymatic properties have been discovered from native methylotrophs. Nicotinamide adenine dinucleotide (NAD)-dependent MDHs are widely used in constructing synthetic methylotrophs, whereas this type of MDH usually suffers from low methanol oxidation activity and low affinity to methanol. Consequently, methanol oxidation is considered as a rate-limiting step of methanol metabolism in synthetic methylotrophs. To accelerate methanol oxidation, thereby improving the methanol utilization efficiency of synthetic methylotrophs, massive researches have focused on discovery and engineering of MDHs. In this review, we summarize the ongoing efforts to discover, characterize, and engineer various types of MDHs as well as the applications of MDHs in synthetic methylotrophs. Directed evolution of MDH and construction of multi-enzyme complexes are described in detail. In the future prospective part, we discuss the potential strategies of growth-coupled protein evolution and rational protein design for acquisition of superior MDHs.

Abstract:Nano-metallic materials are playing an important role in the application of medicine, catalysis, antibacterial and anti-toxin due to their obvious advantages, including nanocrystalline strengthening effect, high photo-absorptivity, high surface energy and single magnetic region performance. In recent years, with the increasing consumption of global petrochemical resources and the aggravation of environmental pollution, nanomaterials based on bio-based molecules have aroused great concern. Bio-based molecules refer to small molecules and macromolecules directly or indirectly derived from biomass. They usually have good biocompatibility, low toxicity, degradability, wide source and low price. Besides, most bio-based molecules have unique physical, chemical properties and physiological activity, such as optical activity, acid/alkali amphoteric property, hydrophilic property and easy coordination with metal ions. Thus, the corresponding nano-materials based on bio-based molecules also have unique functions, such as anti-inflammatory, anti-cancer, anti-oxidation, antiviral fall blood sugar and blood fat etc. In this paper, we give a comprehensive overview of the preparation and application of nano-metallic materials based on bio-based molecules in recent years.

Abstract:Proteases are widely found in organisms participating in the decomposition of proteins to maintain the organisms’ normal life activities. Protease inhibitors regulate the activities of target proteases by binding to their active sites, thereby affecting protein metabolism. The key amino acid mutations in proteases and protease inhibitors can affect their physiological functions, stability, catalytic activity, and inhibition specificity. More active, stable, specific, environmentally friendly and cheap proteases and protease inhibitors might be obtained by excavating various natural mutants of proteases and protease inhibitors, analyzing their key active sites by using protein engineering methods. Here, we review the studies on proteases’ key active sites and protease inhibitors to deepen the understanding of the active mechanism of proteases and their inhibitors.

Abstract:A novel β-glucosidase BglD2 with glucose and ethanol tolerant properties was screened and cloned from the deep-sea bacterium Bacillus sp. D1. The application potential of BglD2 toward polydatin-hydrolyzing was also evaluated. BglD2 exhibited the maximal β-glucosidase activity at 45 °C and pH 6.5. BglD2 maintained approximately 50% of its origin activity after incubation at 30 °C and pH 6.5 for 20 h. BglD2 could hydrolyze a variety of substrates containing β (1→3), β (1→4), and β (1→6) bonds. The activity of β-glucosidase was enhanced to 2.0 fold and 2.3 fold by 100 mmol/L glucose and 150 mmol/L xylose, respectively. BglD2 possessed ethanol-stimulated and -tolerant properties. At 30 °C, the activity of BglD2 enhanced to 1.2 fold in the presence of 10% ethanol and even remained 60% in 25% ethanol. BglD2 could hydrolyze polydatin to produce resveratrol. At 35 °C, BglD2 hydrolyzed 86% polydatin after incubation for 2 h. Thus, BglD2 possessed glucose and ethanol tolerant properties and can be used as the potential candidate of catalyst for the production of resveratrol from polydatin.

Abstract:Wheat quiescin sulfhydryl oxidase was expressed in Escherichia coli for developing a new biological flour improver. The synthesized wqsox gene was constructed into the vector pMAL-c5x and expressed in E. coli, then the expression conditions of recombinant protein was optimized. The MBP fusion label in recombinant protein was removed by protease digestion after affinity purification. Moreover, enzymatic properties of the purified wQSOX and its effect on bread quality were investigated. The synthesized wqsox gene contained 1 359 bp and encoded 453 amino acids with a deduced molecular weight of 51 kDa. The constructed recombinant vector pMAL-c5x-wqsox could successfully express soluble recombinant protein MBP-wQSOX in E. coli Rosetta gamiB(DE3), and the optimal induced expression conditions for recombinant protein were 25 °C, 0.3 mmol/L IPTG and 6 h. MBP fusion tag was cut out by factor Xa protease and wQSOX was prepared after affinity purification. wQSOX could catalyze the oxidation of DTT, GSH and Cys, accompanying the production of H2O2, and exhibited the highest substrate specificity for DTT. Furthermore, enzymatic properties results demonstrated that the optimal temperature and pH for wQSOX catalyzing oxidation of DTT was 50 °C and 10.0, respectively, and wQSOX presented a good stability under high temperature and alkaline environment. The addition of wQSOX with 1.1 U/g flour significantly (P<0.05) increased 26.4% specific volume of the bread, and reduced 20.5% hardness and 24.8% chewiness of bread crumb compared to the control, indicating a remarkable ability to improve the quality of bread.

Abstract:Proton-pumping rhodopsin (PPR) is a simple photosystem widely distributed in nature. By binding to retinal, PPR can transfer protons from the cytoplasmic to the extracellular side of the membrane under illumination, creating a proton motive force (PMF) to synthesize ATP. The conversion of light into chemical energy by introducing rhodopsin into nonphotosynthetic engineered strains could contribute to promoting growth, increasing production and improving cell tolerance of microbial hosts. Gloeorhodopsin (GR) is a PPR from Gloeobacter violaceus PCC 7421. We expressed GR heterologously in Escherichia coli and verified its functional activity. GR could properly function as a light-driven proton pump and its absorption maximum was at 539 nm. We observed that GR was mainly located on the cell membrane and no inclusion body could be found. After increasing expression level by ribosome binding site optimization, intracellular ATP increased, suggesting that GR could supply additional energy to heterologous hosts under given conditions.

Abstract:To effectively solve the serious impact of high oil in the kitchen wastewater on the downstream treatment process, an excellent oil-degrading strain Aeromonas allosaccarophila CY-01 was immobilized to prepare Chitosan-Aeromonas pellets (CH-CY01) by using chitosan as a carrier. Oil degradation condition and efficiency of CH-CY01 pellets were assessed. The growth of immobilized CH-CY01 was almost unaffected, and the maximum degradation rate of soybean oil was 89.7%. Especially at 0.5% NaCl concentration, oil degradation efficiency of CH-CY01 was increased by 20% compared with free cells. In the presence of a surfactant (sodium dodecylbenzene sulfonate) at 1 mg/L, the degradation efficiency of oil by CH-CY01 was increased by 40%. Moreover, using the high-oil catering wastewater as the substrate, more than 80% of the solid oil was degraded with 1% (V/V) CH-CY01 pellets treatment for 7 days, significantly higher than that of free cells. In summary, immobilized CH-CY01 significantly improved the efficiency of oil degradation.

Abstract:Microcystis aeruginosa, a type of algal bloom microalgae, is widely distributed in water, causing serious deteriorated effects on humans and the ecological environment. As a biocontrol microorganism, Bacillus subtilis can synthesize various bioactive substances through non-ribosomal peptide synthetase, to inhibit the growth of M. aeruginosa. Thus, it is imperative to investigate the non-ribosomal peptide (NRP) metabolites of B. subtilis fmb60. Three NRP metabolites from B. subtilis fmb60 including bacillibactin, surfactin and fengycin were extracted and identified by genome mining technology. The growth inhibition of M. aeruginosa was studied by adding various concentrations of NRP metabolites. The half-effect concentration value (EC50.4 d) of M. aeruginosa was 26.5 mg/L after incubation for 4 days. With the increasing concentration, the inhibitory effects of NRP metabolites of B. subtilis fmb60 on M. aeruginosa was enhanced significantly. Compared with the control group, with the addition of 50 mg/L NRP metabolites to the M. aeruginosa, the content of Fv/Fm, Fv/Fo and Yield parameter after cultured for 4 days were decreased by 2.8%, 1.7% and 2.0%, respectively. Those findings indicate that the NRP metabolites of B. subtilis fmb60 can significantly inhibit the photosynthesis and metabolism of M. aeruginosa, which provides a theoretical foundation for the development of biological algae inhibitor of B. subtilis.

Abstract:One of the distinct characters of Latrodectus tredecimguttatus is that its toxic components exist not only in the venomous glands, but also in the tissues outside the venomous glands and even in the eggs. Investigation on the toxins outside the venomous glands can deepen our understanding of spider toxins and discover new lead molecules with important application prospects. In order to explore the low-abundance proteinaceous toxins in the L. tredecimguttatus eggs, we used bioinformatic strategies to mine a gene sequence encoding a peptide toxin from the transcriptome of L. tredecimguttatus eggs, and then heterologously expressed the gene successfully with a 3′-RACE combined with nest PCR strategy. Biological activity analyses indicated that the expressed peptide toxin, named latroeggtoxin-Ⅵ (LETX-Ⅵ), could inhibit Na+ channel currents in ND7/23 cells and promote dopamine release from PC12 cells, without obvious toxicity against Periplaneta americana and bacteria as well as fungi including Staphylococcus aureus and Candida albicans, demonstrating that LETX-Ⅵ is a mammal-specific neurotoxin with a potential application prospect in development of the tool reagents for neurobiological study and the drugs for treating related diseases.

Abstract:The high performance liquid chromatography (HPLC) and enzyme-linked immunoassay (ELISA) were used to investigate the changes of collagen and matrix metalloproteinase-1 (MMP-1) in liver, lung and kidney during growth process of mice. The mice from 0 to 18 weeks were used as the research objects. The contents and proportions of hydroxyproline (Hyp), which were used to calculate the collagen contents, in liver, lung and kidney of different weeks were analyzed with HPLC. The contents and activity of MMP-1 in liver, lung and kidney of different weeks were analyzed with ELISA. The results showed that the collagen contents in liver, lung, and kidney were different (Lung(COL)>Kidney(COL)>Liver(COL)), and they all increased first and then decreased with weeks. The collagen contents in liver, lung, and kidney reached the highest level in the ninth (5.52 ng/mg), sixth (54.10 ng/mg) and ninth (19.20 ng/mg) week, respectively. Then it declined slowly from 9 to 18 weeks. The result of ELISA showed that the MMP-1 contents in liver, lung and kidney decreased first and then increased with weeks, and the trend of MMP-1 activity was opposite. It indicated that the increase of collagen contents in the tissues will inhibit the secretion of MMP-1.

Abstract:The transposon vector containing enhanced green fluorescent protein (EGFP) was injected into early housefly (Musca domestica L.) eggs by microinjection method to realize stable gene expression in vivo for verification, and to study housefly gene function. A borosilicate glass micro injection needle suitable for microinjection of housefly eggs was made, the softening treatment conditions of housefly egg shells were explored, and a microinjection technology platform suitable for housefly was constructed with a high-precision microsyringe Nanoject Ⅲ as the main body. The recombinant plasmid PiggyBac-[3×P3]-EGFP containing the eye-specific 3×P3 promoter and EGFP and the stable genetic expression helper plasmid pHA3pig helper were microinjected into the treated housefly eggs. After emergence, the eye luminescence was observed, and the expression and transcription level of EGFP were detected. The results showed that the normal hatching rate of housefly eggs was 55% when rinsed in bleaching water for 35 s. The hardness of the egg shell treated for 35 s was suitable for injection and the injection needle was not easy to break. About 3% of the emerged housefly eyes had green fluorescence. Through further molecular detection, EGFP specific fragments with a size of 750 bp were amplified from DNA and RNA of housefly. Through the technical platform, the stable expression of reporter genes in housefly can be conveniently and effectively realized, and a bioreactor with housefly as the main body can be established, which provides certain reference value for subsequent research on housefly gene function.

Abstract:We developed a high-efficiency microfluidic chip for extracting exosomes from human plasma. We collected peripheral blood from normal human, designed and fabricated a microfluidic chip based on nanoporous membrane and agarose gel electrophoresis to isolate exosomes. The extracted exosomes were characterized by transmission electron microscopy, nanosight and Western blotting, the morphology, concentration and particle size of exosomes were identified and analyzed. Meanwhile, we used ultracentrifugation and microfluidic chip to isolate exosomes separately. The particle size and concentration of the exosomes extracted by two methods were compared and analyzed, and their respective extraction efficiency was discussed. Finally, the expression level of miRNA-21 in exosomes was analyzed by RT-PCR. The microfluidic chip isolated (in 1 hour) high-purity exosomes with size ranging from 30–200 nm directly from human plasma, allowing downstream exosomal miRNA analysis. By comparing with ultracentrifugation, the isolation yield of microfluidic chip was 3.80 times higher than ultracentrifugation when the volume of plasma sample less than 100 μL. The optimized parameters for exosome isolation by gel electrophoresis microfluidic chip were: voltage: 100 V; concentration of agarose gel: 1.0%; flow rate of injection pump: 0.1 mL/h. The gel electrophoresis microfluidic chips could rapidly and efficiently isolate the exosomes, showing great potential in the research of exosomes and cancer biomarkers.

Abstract:Nucleic acid detection technique has good sensitivity and specificity and is widely used in in vitro diagnosis, animal and plant commodity quarantine, forensic identification, and other fields. However, it is susceptible to carryover contamination during the operation and leads to false-positive results, which seriously affects the detection accuracy. Therefore, finding an effective solution to prevent and eliminate nucleic acid carryover contamination has become particularly urgent. This study compared several different methods for removing nucleic acid contamination and confirmed that sodium hypochlorite solution and PCRguard reagent could effectively eliminate nucleic acid carryover in the liquid and on surfaces of different materials. Besides, the combination of sodium hypochlorite solution and PCRguard can solve the nucleic acid aerosol contamination. This study proposes solutions for the routine prevention of carryover contamination and removal of aerosol that has occurred in molecular diagnostic laboratories.

Abstract:In the era of Internet +, teaching models in universities are undergoing changes due to the rapid development of information technology. Blended teaching, combining online with offline teaching, is being implemented and developed in universities. In order to reform teaching mode and improve teaching effect, the curriculum team carried out the exploration of blended teaching reform for the “Introduction to Life Sciences” for non-biology students. The course combined high-level MOOC (Massive Open Online Course), small class teaching, diversified platform and multi-dimensional teaching mode, built a multi-disciplinary collaborative teaching team, formed a multi-dimensional evaluation system focusing on process and ability, practiced the education concept of combining knowledge teaching and value leading, gained valuable practical experience, and achieved the expected teaching results. It can provide reference for the reform and construction of similar courses in other colleges and universities. The development of blended teaching expands the breadth and depth of teaching, stimulates students’ interest and potential for learning, opens up students’ thinking and perspective, cultivates students’ scientific literacy and comprehensive ability, and plays a positive role in the cultivation of innovative and inter-disciplinary talents.

Abstract:Fermentation engineering is an industrial process that uses the transformation of microorganisms or other cells to produce a specific product in a specific bioreactor. Fermentation engineering has developed from an ancient food fermentation relying solely on experience accumulation to an important production mode of food, agriculture, medicine, chemical industry and other means of production and life. It has become a key technology to support the sustainable development of human beings, and is inseparable from the continuous progress of interdisciplinary technology. The interdisciplinary integration and the continuous upward movement of China’s global industrial chain will inevitably put forward higher requirements for the cultivation of fermentation engineering composite talents in the new situation. In order to constantly improve the interdisciplinary fermentation engineering compound talent training system, in recent years, the research lab has been refining and improving the concept of talent training, and actively deepening the reform of talent training system. Systematic research and practice have been carried out around the aspects of training program, enrollment system, teacher background, subject setting, scientific research practice, evaluation system, etc., which has promoted the technological progress of fermentation engineering and related supporting industries, and contributed an important force to the transformation of China from a big fermentation country to a powerful fermentation country.

Abstract:The training effects of experimental courses determine the practical abilities of undergraduate students. Therefore, it is essential to establish a comprehensive experimental course system that adapts to the undergraduate education of environmental science. Here, we introduce the “basic-specialized-comprehensive” experimental course system of Xiamen University, which is established following the principles of being systematic, comprehensive, and modular. To establish this course system, we first increased the investment of lab facilities and enhanced the management of student labs. Then, we improved the contexts of teaching and training according to the requirements of industry and society. Showing how this course system is developed stepwise and the training effects of this system, we hope to provide a reference for the experimental courses of environmental science in colleges and universities.