Recent Researches of Bioactive Metabolites in Marine Organisms-associated Microorganisms

Recent researches have shown that some compounds isolated from marine organisms have striking structural similarities with the metabolites from known microorganisms. It is inferred from the researches that the symbiotic or associated marine microorganisms may be the true sources of those compounds or at least involved in the biosynthesizing process. This view has been further evidenced by the researches for many sponges and sponge-associated microorganisms. Importantly, growing evidence has highlighted that the symbiotic or associated marine microorganisms live in the microenvironment within the hosts, and they also produce secondary metabolites which are new and original in structure and unique in activity. All these suggest that the microorganisms associated with marine organisms are the sources with very high potential to be new natural bioactive agents. This article reviews briefly the research advances in the study of new bioactive metabolites from marine organisms-associated microorganisms since 2000.

Application of Biological Nanopore Sequencing Technology in the Detection of Microorganisms

Environmental pollution and the spread of pathogenic microorganisms pose a significant threat to the health of humans and the planet.Thus,understanding and detecting microorganisms is crucial for maintaining a healthy living environment.Nanopore sequencing is a single-molecule detection method developed in the 1990s that has revolutionized various research fields.It offers several advantages over traditional sequencing methods,including low cost,label-free,time-saving detection speed,long sequencing reading,real-time monitoring,convenient carrying,and other significant advantages.In this review,we summarize the technical principles and characteristics of nanopore sequencing and discuss its applications in amplicon sequencing,metagenome sequencing,and whole-genome sequencing of environmental microorganisms,as well as its in situ application under some special circumstances.We also analyze the advantages and challenges of nanopore sequencing in microbiology research.Overall,nanopore sequencing has the potential to greatly enhance the detection and understanding of microorganisms in environmental research,but further developments are needed to overcome the current challenges.

Bioremediation of nitrogen-and phosphorus-polluted aquaculture sediment by utilizing combined immobilized effective microorganisms and sediment aeration technology

The endogenous release of nitrogen and phosphorus from aquaculture sediment can continuously pollute the water quality in aquaculture ponds.In this study,an integrated bioremediation approach that combined effective microorganisms(EM)with aeration techniques was designed to restore contaminated aquaculture sediment.Initially,a set of laboratory-scale experiments was designed to evaluate the feasibility of the technology for the bioremediation of nitrogen and phosphorus.The removal and transformation efficiency indexes of both the overlying water and sediment were measured.From the obtained results,the combination of sediment aeration and immobilized EM significantly improved the nitrogen and phosphorus removal rate from the overlying water and sediment when compared to other methods.Subsequently,a series of field-scale experiments was further implemented to assess the integrated technique in practical applications.In field experiments,the variation in the comprehensive trophic level index(TLI)and sediment biodegradation activities(G value)was used to assess the effect of sediment bioremediation.In pond II which promotes sediment biodegradation,the values of TLI varied from 70.13 to 54.16,and the classification level changed from Hypereutrophic to a Light eutrophic.In addition,the G value increased from 0.98 kg/(kg·h)to 2.12 kg/(kg·h).The organic matter(OM)and sediment thickness(ST)decreased by 17.4 g/kg and 2.3 cm,respectively.The obtained results indicated that the combination of EM and sediment aeration might be feasible and effective for the remediation of nitrogen-and phosphorus-polluted aquaculture sediment.

New Type Bio-composites Containing Nitrogenous Fertilizers of Prolonged Action and Nitrogen-Fixing Microorganisms

Technology was developed for obtaining ecologically pure composites containing nitrogenous fertilizers of prolonged action and nitrogen-fixing microorganisms in order to increase productivity of cereal crops. As a result of application of this composite nitrogenous fertilizer hectare norm decreases by 40%-55%, while productivity increases by 15%-30%, compared to those of the control.

Biotechnology Applications of Plant Callus Cultures

In ethnopharmacology, and especially in traditional Chinese medicine, medicinal plants have been used for thousands of years. Similarly, agricultural plants have been used throughout the history of mankind. The recent development of the genetic engineering of plants to produce plants with desirable features adds a new and growing dimension to humanity’s usage of plants. The biotechnology of plants has come of age and a plethora of bioengineering applications in this context have been delineated during the past few decades. Callus cultures and suspension cell cultures offer a wide range of usages in pharmacology and pharmacy (including Chinese medicine), as well as in agriculture and horticulture. This review provides a timely overview of the advancements that have been made with callus cultures in these scientific fields. Genetically modified callus cultures by gene technological techniques can be used for the synthesis of bioactive secondary metabolites and for the generation of plants with improved resistance against salt, draft, diseases, and pests. Although the full potential of callus plant culture technology has not yet been exploited, the time has come to develop and market more callus culture-based products.

Omics Technologies Reveal Abundant Natural Variation in Metabolites and Transcripts among Conventional Maize Hybrids

In this report we have evaluated metabolite and RNA profiling technologies to begin to understand the natural variation in these biomolecules found in commercial-quality, conventional (non-GM) maize hybrids. Our analyses focus on mature grain, the article of commerce that is most typically subjected to the rigorous studies involved in the comparative safety assessment of GM products. We have used a population of conventionally-bred maize hybrids that derive from closely related inbred parents grown under standard field conditions across geographically similar locations. This study highlights the large amount of natural variation in metabolites and transcripts across conventional maize germplasm grown under normal field conditions, and underscores the critical need for further extensive studies before these technologies can be seriously considered for utility in the comparative safety assessment of GM crops.

Advances in single-cell sequencing technology in microbiome research

With the rapid development of histological techniques and the widespread applica-tion of single-cell sequencing in eukaryotes,researchers desire to explore individual microbial.genotypes and functional expression,which deepens our understanding of microorganisms.In this review,the history of the development of microbial detection technologies was revealed and the difficulties in the application of single-cell sequencing in microorganisms were dissected as well.Moreover,the characteristics of the currently emerging microbial single-cell sequencing(Microbe-seq)technology were summarized,and the prospects of the application of Microbe-seq in microorganisms were distilled based on the current development status.Despite its mature development,the Microbe-seq technology was still in the optimization stage.A retrospective study was conducted,aiming to promote the widespread application of single-cell sequencing in microorganisms and facilitate further improvement in the technol-ogy.

Advances in airborne microorganisms detection using biosensors:A critical review

Humanity has been facing the threat of a variety of ifectious diseases.Airborne microorganisms can cause airbome infectious diseases,which spread rapidly and extensively,causing huge losscs to human society on a global scale.In recent years,the detection technology for airbome microorganisms has developed rapidly;it can be roughly divided into biochemical,immune,and molecular technologies.However,these technologies still have some shortcomings;they are time consuming and have low sensitivity and poor stability.Most of them need to be used in the ideal environment of a laboratory,which limits their applications.A biosensor is a device that converts biological signals into detectable signals.As an interdisciplinary feld,biosensors have successfully introduced a variety of technologies for bio-detection.Given their fast analysis speed,high sensitivity good portability,strong specifcity,and low cost,biosensors have been widely uised in cnvironmental monitoring,medical research,food and agricultural safety,military.medicine and other fields.In recent years,the performance of biosensors has greatly improved,becoming.a promising techmology for airborne microorganism detection.This review introduces the detection principle of biosensors from the three aspects of component identification,energy conversion principle,and signal amplification.It also summarizes its research and application in airborne microorganism detection.The new progress and future development trend of the biosensor detection of airbormne microorganisms are analyzed.

Biosurfactant-assisted phytoremediation of potentially toxic elements in soil:Green technology for meeting the United Nations Sustainable Development Goals

Biosurfactants are biomolecules produced by microorganisms, low in toxicity, biodegradable, and relatively easy to synthesize using renewable waste substrates. Biosurfactants are of great importance with a wide and versatile range of applications, including the bioremediation of contaminated sites. Plants may accumulate soil potentially toxic elements(PTEs), and the accumulation efficacy may be further enhanced by the biosurfactants produced by rhizospheric microorganisms. Occasionally, the growth of bacteria slows down in adverse conditions, such as highly contaminated soils with PTEs. In this context,the plant's phytoextraction capacity could be improved by the addition of metal-tolerant bacteria that produce biosurfactants. Several sources, categories,and bioavailability of PTEs in soil are reported in this article, with the focus on the cost-effective and sustainable soil remediation technologies, where biosurfactants are used as a remediation method. How rhizobacterial biosurfactants can improve PTE recovery capabilities of plants is discussed, and the molecular mechanisms in bacterial genomes that support the production of important biosurfactants are listed. The status and cost of commercial biosurfactant production in the international market are also presented.

Wildlife-borne microorganisms and strategies to prevent and control emerging infectious diseases

China is one of the countries with the richest wildlife population.The large variety of widely distributed species act as natural or susceptible hosts for numerous infectious diseases.It is estimated that there are more than 1.2 million unknown virus species in China,and there might be 10,000–30,000 unknown bacteria in wild mammals on the Qinghai-Tibet Plateau alone.There are no less than 600,000 species of animal-borne parasites and approximately 2 million species of fungi worldwide.With rapid economic growth and globalization,humans and wildlife interact more frequently,which enhances the probability of wildlife-borne pathogens infecting humans.The occurrence of animal-borne infectious diseases will become the“new normal”we have to face in the future.Therefore,research should be carried out on wildlife-borne microorganisms and the prevention and control of emerging infectious diseases to establish an analytical framework and an evaluation technology system for risk assessment and early warning of potential animal-borne emerging infectious diseases.This will not only improve our understanding of wildlife-borne microbial communities but also enable in-depth analysis,discovery,early warning,and even prediction of major animal-borne emerging infectious diseases that might occur in the future.Furthermore,this research will reduce response times,minimize the social and economic impact and losses,enable interventions related to the emergence or spread of the disease as early as possible,and comprehensively improve our management of infectious disease outbreaks.

Co-culture:stimulate the metabolic potential and explore the molecular diversity of natural products from microorganisms

Microbial secondary metabolites have long been considered as potential sources of lead compounds for medicinal use due to their rich chemical diversity and extensive biological activities.However,many biosynthetic gene clusters remain silent under traditional laboratory culture conditions,resulting in repeated isolation of a large number of known compounds.The co-culture strategy simulates the complex ecological environment of microbial life by using an ecology-driven method to activate silent gene clusters of microorganisms and tap their metabolic potential to obtain novel bioactive secondary metabolites.In this review,representative studies from 2017 to 2020 on the discovery of novel bioactive natural products from co-cultured microorganisms are summarized.A series of natural products with diverse and novel structures have been discovered successfully by co-culture strategies,including fungus-fungus,fungus-bacterium,and bacterium-bacterium co-culture approaches.These novel compounds exhibited various bioactivities including extensive antimicrobial activities and potential cytotoxic activities,especially when it came to disparate marine-derived species and cross-species of marine strains and terrestrial strains.It could be concluded that co-culture can be an effective strategy to tap the metabolic potential of microorganisms,particularly for marine-derived species,thus providing diverse molecules for the discovery of lead compounds and drug candidates.

Distribution of the indigenous microorganisms and mechanisms of their orientational activation in Daqing Oilfield

The distribution of indigenous microorganisms was surveyed in Block 1 of Daqing Oilfield. Based on this survey,the indigenous microorganisms in the formation water were activated with different activator systems at the simulated stratum ecological environment. The changes of the number of bacteria of various physiological groups were determined during the process of activation. Also changes of pH value and composition of gas productions were analyzed at the end of culturing. The results showed that the selected block formation water contained a great number of saprophytic bacteria,hydrocarbon-oxidizing bacteria,fermentative bacteria,methane-producing bacteria and sulfate-reducing bacteria. Under the conditions that the growth of sulfate-reducing bacteria was controlled the block had the potential to enhance oil recovery by activating beneficial bacteria. The growth of sulfate-reducing bacteria can be inhibited through the activation of nitrate-reducing bacteria. The number of nitratereducing bacteria reached 106―107 cells/mL,but sulfate-reducing bacteria reached only 0―45 cells/mL in A system. Methane-producing bacteria can be activated by C,D activators. The relative content of biological methane in the light hydrocarbon gas reached 80% in C,D systems. B activator was conducive to the propagation of acid-producing bacteria,so that the pH value of the culture medium decreased from 7.5 to around 5.0. Hydrocarbon-oxidizing bacteria can be activated by various activator systems. There was low molecular light hydrocarbon in gas production according to the analysis of gas chromatograph. According to the content of methane and the number of methane-producing bacteria,methane only can be generated through activating methane-producing bacteria. By choosing different activator systems,various populations of indigenous microorganisms can be activated accordingly.

微生物代谢产物调控胃肠道发育的机制

动物胃肠道中栖息着大量微生物,这些微生物通过代谢产物参与调控宿主新陈代谢、生理免疫和发育过程等。深入了解胃肠道微生物及代谢产物的调控机制,有利于人们采用相应技术手段促进胃肠道健康发育,提高动物生产性能。文章综述了胃肠道微生物产生的不同种类的代谢产物,介绍了这些代谢产物在调控宿主发育中的作用及其机制,以期为通过营养途径调节微生物代谢产物促进动物胃肠道发育提供理论依据。

微生物在生物基催化剂制备中的应用

随着工业催化过程对环境友好水平和效率需求的日益增长,微生物的功能多样性和环境适应性使其成为了生物基催化剂制备的理想选择。微生物以其固有的酶系统提供了一种高效、特异性强的催化方式,有利于生物基催化剂制备。微生物催化剂在药物合成、生物燃料生产和环境保护等多个领域展现了广泛的应用潜力。因此,文章将探讨微生物在生物基催化剂制备中的应用,以期为相关领域提供理论参考。

分子生物学技术在食品病原微生物检测中的应用探索

随着食品安全问题日益凸显,快速准确地检测病原微生物显得尤为重要。分子生物学技术以其灵敏度高、特异性强、检测时间短等优势,在食品病原微生物检测中展现出巨大的应用潜力。本文首先介绍分子生物学技术在食品病原微生物检测中的应用意义,然后分析应用存在的问题,最后提出有效的应对策略。未来,随着技术的不断进步与创新,分子生物学技术在食品安全检测领域将发挥更加重要的作用。

乳制品中有害微生物检测新技术研究进展

乳及乳制品因营养丰富而成为沙门氏菌(Salmonella)、金黄色葡萄球菌(Staphylococcus aureus)、单核细胞增生李斯特菌(Listeria monocytogenes)、克罗诺杆菌(Cronobacter)和蜡样芽孢杆菌(Bacillus cereus)等多种有害微生物的天然培养基,近年来,乳制品安全事件屡见不鲜,已成为食品安全研究热点。传统检测技术因检测周期长且准确率低,无法满足乳制品安全检测高通量、时间短的需求。随着分子生物学和免疫学的发展,重组酶介导等温核酸扩增(recombinase aided amplification,RAA)技术、环介导等温扩增(loop-mediated isothermal amplification,LAMP)技术、纳米探针技术和三磷酸腺苷(adenosine triphosphate,ATP)发光技术等因灵敏度高、检测时间短被逐渐应用于乳品安全检测。鉴于此,本文结合国内外相关研究,从乳制品安全角度出发,重点介绍了上述技术在乳制品安全检测中的研究现状,并进行了分析讨论,以期对未来乳制品有害微生物快速检测技术的发展提供思路。

微生物固定化技术及在废水处理中的应用

在探究了微生物固定化技术在不同废水环境中的应用情况后,总结了不同微生物固定方法且比较了各种方法的优缺点,并对微生物固定化载体的选择因素及材料分类进行说明。最后,简要讨论了微生物固定化技术在水污染治理实际应用中所存在的问题,并对未来的研究提供了参考方向。

生鲜乳中16种致病微生物多重荧光定量PCR集成检测技术的建立与初步应用

为满足生鲜乳中微生物快速通量检测的需求,建立多重荧光定量PCR集成方法,从而快速检测生鲜乳中潜在的16种致病微生物,通过设计致病性大肠杆菌、金黄色葡萄球菌、链球菌等目标菌株的特异性引物和探针,优化反应体系,验证方法的特异性、敏感性等,建立了稳定的4组多重集成荧光定量PCR反应体系,并利用人工污染的生鲜乳样品对所建立的方法和传统培养法进行了验证比较。结果显示:各对引物探针对目标菌株均能有效识别并扩增,每组体系中引物探针未发现交叉反应,对其余3组体系的12株非目标菌均未有特异性反应;组内和组间变异系数均低于3%;该方法对布鲁氏菌的最低检出限为10^(2) CFU/mL,对阪崎肠杆菌、志贺菌、沙门菌等7种致病微生物的最低检出限为10^(3) CFU/mL,对蜡样芽胞杆菌、弯曲杆菌、结核分枝杆菌等8种致病微生物的最低检出限为10^(4) CFU/mL;所建方法和传统培养法对人工污染不同致病菌的各25份样品检测结果基本一致。结果表明,本研究建立的多重集成荧光定量PCR方法灵敏度高,特异性及重复性好,可实现对生鲜乳样品中多种致病微生物的快速高效检测,为生鲜乳微生物性风险监测提供了技术支撑。

果酒生产中腐败微生物及其防控研究进展

我国果酒种类丰富、发展迅速。果酒酿造过程是酵母、细菌、丝状真菌等多种微生物动态演替进化的变化过程,微生物在发酵中的代谢活动是影响果酒产品质量的关键因素。然而,腐败微生物不仅会降低果酒的感官品质和商业价值,还会威胁到消费者的身体健康。监测和控制果酒中腐败微生物是保障果酒高质量发展的重要手段。因此,该文综述了不同类型果酒中主要腐败微生物的类群、来源及其不良产物,探讨了检测和避免微生物污染的主要方法及其优缺点,旨在为预防和规避果酒生产中腐败微生物带来的危害提供技术参考。

生物炭-蚯蚓原位对设施番茄根际微生物和果实代谢的影响

为改善设施番茄过量施用化肥、品质和产量下降等问题,采用不同土壤改良措施,以‘粉宴1号’番茄为试验材料,设置空白对照(CK)、生物炭(B)、蚯蚓原位(V)、生物炭+蚯蚓原位(BV)4个处理,研究番茄生长发育过程中根区土壤理化性质和土壤根际微生物的变化以及番茄盛果期果实产量和品质的差异,解析不同处理果实代谢物组成的差异。结果表明:BV处理显著提高了土壤速效氮、速效磷和速效钾含量,与CK相比分别提高174.00%、7.44%和45.00%;BV处理显著提高了蔗糖酶活性比CK提高62.02%,V处理显著提高脲酶活性,较CK提高39.72%。BV处理显著提高了土壤细菌Simpson指数,V处理显著提高了土壤真菌Ace、Chao1指数;B处理明显改变了土壤细菌相对丰富占比,其中变形菌门增加最多(45.48%),酸杆菌门和芽单孢菌门降低幅度最大,分别为14.90%和25.70%;对于土壤真菌,B处理中子囊菌门相对丰度最高,提升了15.90%,V处理油壶菌门提升最高,为7.24%,罗兹菌门提升次之,为3.11%。同时,各处理可以显著提高果实产量和品质,BV处理的番茄产量最高、品质最好,表现为其生物量、果实产量、可溶性固形物含量、Vc含量、有机酸含量最高;V处理的番茄果实差异代谢物种类最多,与对照相比差异最大,所得的差异物代谢通路最多。