Influence of symbiotic bacteria from lettuce on inactivation of norovirus / 预防医学

Objective@#To demonstrate the effects of symbiotic bacteria from lettuce on inactivation of norovirus（NV）.@*Methods@#Symbiotic bacteria were isolated from the lettuces sampled from farmlands and supermarkets. NV mixed with symbiotic bacteria was set as the experimental group,without symbiotic bacteria as the control group. After the inactivation by high temperature,ultraviolet light（UV）and chlorine dioxide,the ratio of NV amount in the experimental group and the control group was calculated to evaluate the effects of symbiotic bacteria. The mechanism of symbiotic bacteria was revealed by detecting their effects on the protection of viral capsid protein from UV and on the adsorption of NV.@*Results@#Eleven symbiotic bacteria were identified from lettuces,all of which were bacilli,mainly Pseudomonas. Ten symbiotic bacteria could improve the heat-resistant ability of NV,with Microbacterium oryzae,Cupriavidus taiwanensis（SC061204）,Pseudomonas furukawaii,Enterobacter tabaci and Pseudomonas resinovorans（SC061211）more significant. Eleven symbiotic bacteria could improve anti-UV ability of NV,with Pseudomonas putida,Microbacterium oryzae and Enterobacter tabaci more significant. Only one strain of Pseudomonas putida could improve anti-chlorine dioxide ability of NV（Class I hazard）. Pseudomonas putida,Microbacterium oryzae and Enterobacter tabaci could significantly reduce the damage of NV capsid protein. Nine symbiotic bacteria could promote NV adsorption into lettuces,with the promotion rates ranged from 1.04% to 46.73%;while Pseudomonas putida and Pseudomonas resinovorans（SC061211） could restrain NV absorption,with the promotion rates of -6.50% and -19.85%.@*Conclusion@#Symbiotic bacteria from lettuce may enhance the anti-inactivation of NV by protecting capsid protein and promoting adsorption of NV. It is recommended to control the presence of symbiotic bacteria in the process of inactivating NV.

Formulation of Insecticidal Nematode

Insecticidal nematodes or entomopathogenic nematodes (EPNs) in the genera Heterorhabditis and Steinernema are lethal obligate parasites of insect pests. These nematodes carry specific pathogenic bacteria which are released into the insect hemocoel after penetration of the insect host. The economic importance of entomopathogenic nematodes (EPNs) is increasing as the nematodes are amenable for mass production, formulation, handling and application on a large scale and is currently marketed worldwide for use. The objective of the review is to discuss the principles of formulation and quality control, latest development and future perspectives of the EPNs formulation for the successful use of EPNs as bio insecticides.

Research progress in human symbiotic bacteria and their antibacterial molecules / 生物工程学报

With the emergence and globally spread of drug-resistant bacteria, the discovery and development of new antibacterial drugs is imminent. The symbiotic bacteria distributed in different parts of the body can produce a variety of antibacterial molecules to inhibit the colonization and infection of pathogenic bacteria. Human symbiotic bacteria provide a potential treasure house of resource for the research and development of new drugs with broad new molecular structures and action mechanism. With the further development of bioinformatics tools, synthetic biology and omics technology such as genomics, the mining of human symbiotic bacteria antibacterial molecules will be more in-depth and provide an effective way to solve the problem of drug resistance. Here, we review the antimicrobial molecules produced by human symbiotic bacteria and introduce several methods to explore the resources of natural antibacterial drugs. With the development of modern biotechnology, the antimicrobial molecules of human symbiotic bacteria will be more comprehensively and systematically explored and applied.

Research progress on influence of intestinal microflora on peripheral immune organs in mice / 中国免疫学杂志

The study found that the presence of intestinal microbiota is not only important for the metabolism of essential nutrients in the body, but also plays a key role in the development of the body′s immune system in recent years. Partial microbiota, through natural selection and co-evolution with the host, forms symbiotic relationships with host microbes that are inseparable from host physiology in mice. Symbiotic flora affects the formation of the body′s immune system by affecting innate and adaptive immunity and the development of various regulatory mechanisms. The destruction of the microbial ecosystem in the intestine can lead to the occurrence of many diseases,especially those related to the immune system. Peripheral immune organs always receive a number of immune cells colonized by antigen stimulation. So,the intestinal flora plays an important role in maintaining the function of immune cells. This article will investigates the effects of mouse-related intestinal flora on peripheral immune organ function.

Bioactive potential of seagrass bacteria against human bacterial pathogens.

Study of marine organisms for their bioactive potential, being an important part of marine ecosystem, has picked up the rhythm in recent years with the growing recognition of their importance in human life. Investigation was carried out to isolate 32 strains of endo and epiphytic bacteria in 2 seagrass species viz., Syringodium isoetifolium and Cymodocea serrulata. Morphologically different bacterial strains were tested against 5 antibiotic resistant human bacterial pathogens, of which 10 associated bacteria shown inhibitory activity against one or more bacterial pathogens. Minimum inhibitory concentration (MIC) and Minimum bacterial concentration (MBC) determination with extracellular bioactive compounds from the associated bacteria reveals that, the strain ENC 5 showed inhibitory activity against all the bacterial pathogens with the maximum sensitivity against Pseudomonas aeruginosa at the MIC value of 500 µg ml-1.

Experimental Study on the Pathogenesis of Entamoeba gingivalis / 中国寄生虫学与寄生虫病杂志

Objective To study the pathogenesis of Entamoeba gingivalis ( E^g .) and its relation to periodontal diseases.\ Methods Rats were treated with immuno\|inhibitor for one week and the neck of incisor teeth of the rats was bound with steel wire. They were randomly divided into three groups: the first group was infected by E^g . in the periodontal tissue, the second group was infected by symbiotic bacteria (s.b.),and the third group was given physiological saline as control.Observation on the periodontal inflammation was made for each group of rats, and the purulent secretion from periodontal abscess was examined for living pathogens.\ Results The incidence of periodontal diseases in rats infected by E^g . was higher than that of symbiotic bacteria group and that of control ( P