In Vitro Antibacterial Test of Alkaline Hydrogen Water on Four Kinds of Common Pathogenic Microorganisms

[Objective] The paper was to investigate in vitro antibacterial effect of alkaline hydrogen water on Escherichia coli,Salmonella,Pseudomonas aeruginosa and Staphylococcus aureus.[Method] With Cortex cinnamomi extract（1 g/m L） and pure water as the control,the minimal inhibitory concentrations（MIC） against four kinds of common pathogenic microorganisms were tested through microdilution method.[Result] When the alkaline hydrogen water was diluted to 1/8 times of the original concentration,it had significant antibacterial effects on four kinds of common mi-croorganisms with the concentration of 1.5 ×10^5 CFU/m L,which had equivalent effect with C.cinnamomi extract group.[Conclusion]The alkaline hydrogen water has remarkable antibacterial effects on the four kinds of common microorganisms,which may provide a new important way for pre-venting disease occurrence and reducing the harms of pathogenic microorganisms.

Bacteriological Quality of a Forage Grass (<i>Pennisetum purpureum Schumach</i>) Used in Constructed Wetland Removing Domestic Wastewater Pathogenic Microorganism

Constructed Wetlands (CWs) are an adequate wastewater treatment system with possibility to generate income, in particular by the use of plants of economic interest. However, very few studies deal with the bacteriological quality of plants after wastewater treatment. Thermotolerant coliforms and Sulfite-reducing bacteria were investigated on the above-ground biomass of a species of forage plant (Pennisetum purpureum) as well as their removal in an experimental pilot consisting of four beds, for three months. Two beds were planted and two unplanted beds were used as control. Germs in the wastewater were significantly reduced in both filtrates, with higher removal efficiency of 97.4% for Thermotolerant coliforms and 87.5% for Sulfite-reducing bacteria, in the planted bed. Wastewater treatment resulted in bacteriological contamination of the above-ground plant biomass with a significant decreases in number of germs from 660 to 28 CFU/g (Thermotolerant coliforms) and from 15 to 0 CFU/g (Sulfite-reducing bacteria), when the harvest height increased from the base to the upper end of the plants. However, averages of 305 CFU/g of Thermotolerant coliforms and 5 CFU/g of Sulfite-reducing bacteria were obtained in the above-ground plant biomass which would not present any potential risks for a possible use of the plant biomass as fodder. Thus, the use of forage plant suggests good prospects for upgrading said plants for animal feed.

Immunologically effective biomaterials-enhanced vaccines against infection of pathogenic microorganisms

Infectious diseases are severe public health events that threaten global health.Prophylactic vaccines have been considered as the most effective strategy to train the immune system to recognize and clear pathogenic infections.However,the existing vaccines against infectious diseases have several limitations,such as difficulties in mass manufacturing and storage,weak immunogenicity,and low efficiency of available adjuvants.Biomaterials,especially functional polymers,are expected to break through these bottlenecks based on the advantages of biocompatibility,degradability,controlled synthesis,easy modification,precise targeting,and immune modulation,which are excellent carriers and adjuvants of vaccines.This review mainly summarizes the application of immunologically effective polymers-enhanced vaccines against viruses-and bacteria-related infectious diseases and predicted their potential improvements.

A dynamically evolving war between autophagy and pathogenic microorganisms

Autophagy is an intracellular degradation process that maintains cellular homeostasis.It is essential for protecting organisms from environmental stress.Autophagy can help the host to eliminate invading pathogens,including bacteria,viruses,fungi,and parasites.However,pathogens have evolved multiple strategies to interfere with autophagic signaling pathways or inhibit the fusion of autophagosomes with lysosomes to form autolysosomes.Moreover,host cell matrix degradation by different types of autophagy can be used for the proliferation and reproduction of pathogens.Thus,determining the roles and mechanisms of autophagy during pathogen infections will promote understanding of the mechanisms of pathogen-host interactions and provide new strategies for the treatment of infectious diseases.

Access and benefit-sharing of the pathogenic microorganisms such as SARS-CoV-2

With the outbreak of coronavirus disease 2019(COVID-19),it is essential to share pathogens and their data information safely,transparently,and timely.At the same time,it is also worth exploring how to share the benefits of using the provided pathogenic microorganisms fairly and equitably.There are some mechanisms for the management and sharing of pathogenic microbial resources in the world,such as the World Health Organization(WHO),the United States,the Europe,and China.This paper studies these mechanisms and puts forward"PICC"principles,including public welfare principle,interests principle,classified principle,and category principle,to strengthen cooperation,improve efficiency,and maintain biosafety.

Pathogenic microorganism biobanking in China

Pathogenic microbial strains and specimens are crucial national and strategic biological resources.Preservation and management of the pathogenic microbial resources,as an integral component of biosafety,play an important role in the national biosafety system and in the overall framework of national security.Sound preservation and management rely on the effective designation of preservation institutions,strengthened operation and management of preservation institutions,standardized description and data specifications,establishment of preservation information management systems,and promotion of resource-sharing and utilization.Firm protection and efficient sharing and utility of pathogenic microbial resources are expected to make a unique contribution to the sustainable development of the national economy.

Inactivation and risk control of pathogenic microorganisms in municipal sludge treatment:A review

The rapid global spread of coronavirus disease 2019(COVID-19)has promoted concern over human pathogens and their significant threats to public health security.The monitoring and control of human pathogens in public sanitation and health facilities are of great importance.Excessive sludge is an inevitable byproduct of sewage that contains human and animal feces in wastewater treatment plants(WWTPs).It is an important sink of different pollutants and pathogens,and the proper treatment and disposal of sludge are important to minimize potential risks to the environment and public health.However,there is a lack of comprehensive analysis of the diversity,exposure risks,assessment methods and inactivation techniques of pathogenic microorganisms in sludge.Based on this consideration,this review summarizes the control performance of pathogenic microorganisms such as enterovirus,Salmonella spp.,and Escherichia coli by different sludge treatment technologies,including composting,anaerobic digestion,aerobic digestion,and microwave irradiation,and the mechanisms of pathogenic microorganism inactivation in sludge treatment processes are discussed.Additionally,this study reviews the diversity,detection methods,and exposure risks of pathogenic microorganisms in sludge.This review advances the quantitative assessment of pathogenic microorganism risks involved in sludge reuse and is practically valuable to optimize the treatment and disposal of sludge for pathogenic microorganism control.

Removal of pathogenic indicator microorganisms during partial nitrification:the role of free nitrous acid

Digested wastewater contains pathogenic microorganisms and high ammonia concentrations,which can pose a potential risk to public health.Effective removal of pathogens and nitrogen is crucial for the post-treatment of digested wastewater.Partial nitrification-anammox is an energy-saving nitrogen removal process.Free nitrous acid(FNA),an intermediate product of partial nitrification,has the potential to inactivate microorganisms.However,the efficiency and mechanisms of FNA-related inactivation in pathogens during partial nitrification remains unclear.In this study,Enterococcus and Escherichia coli(E.coli)were selected to investigate the efficiency and mechanisms of FNA-related inactivation in partial nitrification process.The results revealed that 83%±13%and 59%±27%of E.coli and Enterococcus were removed,respectively,in partial nitrification process at FNA concentrations of 0.023−0.028 mg/L.When the concentration of FNA increased from 0 to 0.5 mg/L,the inactivation efficiencies of E.coli and Enterococcus increased from 0 to 99.9%and 89.9%,respectively.Enterococcus exhibited a higher resistance to FNA attack compared to E.coli.3D-laser scanning microscopy(3D-LSM)and scanning electron microscopy(SEM)revealed that FNA exposure caused the surface collapse of E.coli and Enterococcus,as well as visible pore formation on the surface of E.coli cells.4',6-Diamidino-2-phenylindole dihydrochloride n-hydrate(DAPI)/propidium iodide(PI)and biomolecule leakage confirmed that inactivation of E.coli and Enterococcus occurred due to breakdown of cell walls and cell membranes.These findings indicate that partial nitrification process can be used for the removal of residual pathogenic microorganisms.

Aggregation-induced emission:recent applications in infectious diseases

Infectious diseases are caused by various pathogenic microorganisms that break through the human immune barrier,then reproduce and mutate in human cells,thus causing invasive disease.Despite many recent scientific and technological advances in fields,such as genetics,chemistry,and protein engineering,and in the efficiency of drug research and development,the discovery and development of novel and potent anti-infectious disease agents have still lagged behind.It is often challenging to keep up with the emergence and mutation of new pathogenic microorganisms,which leads to the emergence of more resistant pathogenic microorganisms.The emergence of aggregation-induced emission(AIE)fluorogens with high luminescence yields and high reactive oxygen species(ROS)production rates provides scientists with a new strategy for the prevention and treatment of pathogenic microorganisms.Due to their advantages in terms of brightness,biocompatibility,photostability,and positive correlation,AIE fluorogens(AIEgens)have great potential in biological applications.This review presents a systemic overview of recent progress in AIEgen-based platforms for the photodynamic therapy(PDT)of infectious diseases,which has emerged as a promising noninvasive alternative to traditional antibiotics for combating the drug resistance of infectious diseases.This review is mainly divided into two parts according to the type of pathogenic microorganisms:a section on bacterial and fungal infections(e.g.,eye,skin,oral cavity,and blood infections),and a section on viral infections.The future prospects and potential clinical applications of AIEgens are also discussed in detail.In addition to motivating further interest in this field,this review is intended to promote ideas for the further exploration of AIEgens and the development of more advanced AIEgens in a broader range of biomedical and clinical applications.

Biobanking: A foundation of life-science research and advancement

As a foundation of life-science research and advancement,biobanking has played a critical role and made tremendous contributions to healthcare,biotechnology,disease control and prevention,as well as bio-conservation for the benefit of all humankind.This paper starts with a brief introduction of basic concepts,history,classification,and significance of biobanking,followed by a discussion on cryobiology fundamentals and key challenges faced by cryopreservation in biobanking.A special case discussion on the cryopreservation and biobanking of pathogenic microorganisms to meet both the unmet needs for biomedical research and the urgent demand for developing countermeasures against the ongoing coronavirus disease 2019(COVID-19)pandemic is highlighted with insightful recommendations for future studies.

The inactivation of bacteriophages MS2 and PhiX174 by nanoscale zero-valent iron:Resistance difference and mechanisms

Pathogenic enteric viruses pose a significant risk to human health.Nanoscale zero-valent iron(nZVI),a novel material for environmental remediation,has been shown to be a promising tool for disinfection.However,the existing research has typically utilized MS2 or f2 bacteriophages to investigate the antimicrobial properties of nZVI,and the resistance difference between bacteriophages,which is important for the application of disinfection technologies,is not yet understood.Here,MS2 and PhiX174 containing RNA and DNA,respectively,were used as model viruses to investigate the resistances to nZVI.The bacteriophage inactivation mechanisms were also discussed using TEM images,protein,and nucleic acid analysis.The results showed that an initial concentration of 10^(6)PFU/mL of MS2 could be completely inactivated within 240 min by 40 mg/L nZVI at pH 7,whereas the complete inactivation of PhiX174 could not be achieved by extending the reaction time,increasing the nZVI dosage,or changing the dosing means.This indicates that the resistance of phage PhiX174 to nZVI was much stronger than that of MS2.TEM images indicated that the viral particle shape was distorted,and the capsid shell was ruptured by nZVI.The damage to viral surface proteins in both phages was examined by three-dimensional fluorescence spectrum and sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE).However,the nucleic acid analysis demonstrated that the nucleic acid of MS2,but not PhiX174,was destroyed.It indicated that bacteriophage inactivation was mainly attributed to the damage of nucleic acids.