Abstract:[Objective] The research aimed to screen the efficient, durable, safe and inexpensive molluscicidal microorganisms against Oncomelania hupensis and observe the molluscicidal effects. [Methods] The four strains (named as B8, B27, B36, B59) which were highly toxic to Oncomelania hupensis were isolated by preliminary screening from snail habitats. The colonial morphology and gram stain were observed by light microscope. The molluscicidal active fraction were analysed by different resolving gel concentration of SDS-PAGE. The ribosomal 16s rRNA of the dominant strain were amplified and the PCR products were sequenced. Sequence alignment was adopted for the identification of the dominant strain. [Results] the four strains were Gram-positive bacilli. According to the comprehensive comparison, molluscicidal effect of the four strains had significant differences in the fermented supernatant (FS) group (χ2=21.286, P=0.002); And then the fermented liquor group had also significant differences (χ2=17.298, P=0.008); The bacteria suspension group had not significant differences (χ2=7.579, P=0.271). In addition, B59 strain showed the higher molluscicidal activity than the other three strains. The snails mortalities in FS group was up to 73.3% and 96.7% by immersion in 48 h and 72 h respectively. SDS-PAGE analysis revealed that there did not exsit protein band in FS of B59 strain and molluscicidal active components might be other materials. Finally, molecula phylogenetic analysis based on ITS sequence showed that strain B59 (accession number in GenBank: KP146144) was the most homologus to 100% Bacillus cereus (accession number: CP001746) with bootstrap. [Conclusion] In summary, The effective molluscicidal components against Oncomelania hupensis exsited in the fermented supernatant of strain B59, which might not be protein. B59 strain was identified as a species of Bacillus cereus.

Abstract:[Objective] Isolation of marine actinobacteria with antagonistic activity against pathogenic Saprolegnia sp., and the antifungal stability of culture broth from the target strain. [Methods] Serial dilution and plating method was employed to isolate actinobacteria from marine sediments. The antagonistic strains were screened by confrontation assay on PDA plates. The anti-Saprolegnia effects were characterized using cell-free culture broth as references. The stability of antagonistic activity was analyzed upon physical and chemical factors changes including temperature, pH, and proteinase treatments. Phylogenetic tree was constructed using the Neighbor-Joining method based on the 16S rRNA gene sequences. [Results] Dozens of actinobacteria strains were isolated, and five of them presented antagonistic activity against Saprolegnia sp. The strain of S26, which showed the strongest activity, was found closely related to Streptomyces violaceus NBRC 13103T (98.6% similarity) based on the 16S rRNA gene sequence analysis. This showed that S26 should be assigned to genus Streptomyces. The inhibition zones were 32.00 mm±0.81 mm for S26 fermented broth against germination of Saprolegnia spores and 39.75 mm±0.50 mm for five times concentrated cell-free culture against growth of Saprolegnia hypha. The minimum to inhibit Saprolegnia spores germination was 3.125% of the total activity of the five times concentrated cell-free culture. The substance responsible for antagonism showed strong resistance to high temperatures and a clear inhibition zone (25.50 mm±0.58 mm in diameter) was still obtained by the fermented broth even after intense heating treatment of 100 °C for 30 min. The antifungal activity of fermented broth was sensitive to extreme acid or alkaline condition (pH<5.0 or pH>9.0), but it was sustained throughout the pH range between 5.0 and 9.0. The active substance was partially sensitive to proteinase treatments. These suggested that it was highly possible for the antagonisitic substances to be both proteinaceous and non-proteinaceous molecules. [Conclusion] The marine actinobacterium strain of S26 isolated in this study showed strong inhibitory effects to the spores germination and hypha growth of Saprolegnia sp., and the compounds with the antagonistic activity were resistant to some extent against temperature, pH and proteinase treatments. These suggested that S26 was a promising microbial strain to control saprolegniasis occurred in aquatic animals. The study implies marine actinobacteria will play an important role in biocontrol of aquatic animal diseases.

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Abstract:[Objective] This study was designed to investigate the binding of two Lactobacillus strains, i.e., L. acidophilus NCFM and L. paralimentarius 412, to plasticizers. Several factors which affect the ability of the bacteria to bind plasticizers were also detected. [Methods] HPLC was used to detect the binding efficiency of two lactobacillus strains to three phthalates plasticizers, namely DEP, DBP and DEHP, respectively. The adsorption conditions of two strains to DBP were optimized when the bacterial cells were subjected to heat, acid or NaCl treatment. [Results] Two Lactobacillus strains showed an adsorption to three phthalic acid esters plasticizers, but strain NCFM was better in binding plasticizers than strain 412, especially in adsorbing the plasticizer DBP. The binding percentages of strain NCFM to three phthalates DEP, DBP and DEHP was 21.48%, 43.32% and 9.62%, respectively. Strain NCFM bound the maximal DBP after incubation for 4 h at 37 °C. The efficiency of strain NCFM plasticizers-adsorbing was significantly improved via heat, acid and NaCl treatment. [Conclusion] L. acidophilus NCFM showed good ability to bind phthalic acid esters plasticizers. Strain NCFM should be a candidate as one of biological tools to remove plasticizers from the environments linked to food products.

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Abstract:[Objective] We studied the effect of Trichoderma viride on resolving Chlorella cell wall. [Methods] The cell wall of Chlorella was resolved by the secretion from free T. viride or immobilized T. viride in sodium alginate and calcium chloride. The activity of cellulases secreted by free T. viride or immobilized T. viride was determined by spectrophotometry. [Results] Cell wall of Chlorella was resolved by 86.5% by the secretion of free T. viride, 34.3% higher than that by cellulases R-10 containing only β-glucosidase. Compared to cellulases R-10, T. viride secretion contained three cellulases, namely, endo-glucanase, exo-glucanase and β-glucosidase. This was probably the reason why T. viride secretion had higher rate of resolving cell wall. Immobilized T. viride could be used repeatedly at least 5 times. The rate of resolving Chlorella cell wall by immobilized T. viride in the first time and the fifth time was 81.5% and 52.1% respectively. [Conclusion] Cell wall of Chlorella can be resolved by the secretion both from free T. viride and immobilized T. viride.

Abstract:[Objective] The aim of this study was to screen bagasse-cellulose degrading-bacteria from seawater environment and to research the influence on bagasse cellulose enzymatic activity by mixed-fermentation of strains. [Methods] Cellulose congo-red culture medium was used to screening, and extracellular enzyme activity as re-screening methods. [Results] Two strains (Z4 and S5) were isolated and identified as Bacillus licheniformis by 16S rRNA gene sequence similarity analysis. Strain S5 possessed the highest filter paper activity (FPA activity) and bagasse cellulose activity which were 1.16 U/mL and 2.80 U/mL respectively. Mixed-fermentation of Z4 and S5 could obviously increase in cellulose enzyme activity. FPA activity and bagasse cellulose activity increased by 40.60% and 14.21% compared to S5. Mixed-fermentation of S5 and Bacillus BZ5 increased FPA activity and bagasse cellulose activity by 6.23% and 25.92% respectively. [Conclusion] Mixed-fermentation can significantly improve the ability of cellulose degradation, Z-4 and S-5 have a potential application in mariculture.

Abstract:[Objective] The diversity and microflora composition of endophytic actinomycetes from Sophora alopecuroides L. in arid and desolate areas of Ningxia were analyzed, which could also provide research methods and theory on rational development and use of endophytic actinomycetes from Sophora alopecuroides L.. [Methods] The endophytic actinomycetes were separated and cultivated from 30 samples of healthy roots, stems, leaves and seeds of Sophora alopecuroides L. by tissue homogenate in six sample plots, where were sampled from different vegetations and soil types in Baijitan Nature Reserve of Ningxia. Endophytic actionmycetes were classified according to their morphological characteristics of culture, bacterial colonies and spores and 16S rRNA gene sequences analysis. Relative frequency (Rf), Shannon-wiener index (F), Margalef index (D) and Sorenson’s similarity coefficient (Cs) were calculated to analyze their characteristics of microflora composition. [Results] 111 endophytic actinomycetes were isolated from 30 samples, and they belong to Streptomyces, Nocardiopsis, Prauserella, Actinophytocola, Microbacterium, Actinosynnema, Thermoleophilum, Glycomyces and Saccharothrix respectively, Streptomyces and Nocardiopsis were dominant genera. The distribution of endophytic actinomycetes from Sophora alopecuroides L. has some degree of tissue preference. Quantities of endophytic actinomycetes from roots and seeds of Sophora alopecuroides L. were more than ones of stems and leaves for the same plant. In different vegetations types, Shannon-wiener index (H′) of endophytic actionmycetes from Sophora alopecuroides L. were most significantly in the sandy weeds (sample Ⅳ) and least in desert steppes (sample Ⅴ). The community of endophytic actinomycetes from Sophora alopecuroides L. of desert steppe (sample Ⅴ) and woodland (sample Ⅵ) has closely similarity. [Conclusion] From the experiment we can see that Sophora alopecuroides L. have abundant resources of endophytic actinomycetes, the species diversity of endophytic actinomycetes communities is affected both by its host preference and by its different habitats.

Abstract:[Objective] In order to solve the environmental pollution problem caused by total petroleum hydrocarbons (TPHs), the wild type strains’ degradation rate of TPHs was enhanced in this study. [Methods] Based on bioremediation technique, the strains, which can degrade TPHs effectively, were isolated from the oilfield produced water and selected out by enrichment culture, prescreening and rescreening. Then, the strains were identified through morphological, physiological, biochemical, and phylogenetic (16S rRNA gene) characterization. In order to obtain highly efficient THPs-degrading strains, after being mutated by UV-plasma and 96-pore plate fermentation, the isolated strains were screened by high-throughput screening method, with the use of multi-functional microplate reader based on the dual wavelength ultraviolet spectrum. At last, the mutants’ hereditary stability was tested by analysis of variance. [Results] The wild strain PW04, which was isolated from produced water, was identified as Sphingobacterium multivorum. After the compound mutation, three highly efficient THPs-degrading strains (S. multivorum PW04-H10, S. multivorum PW04-G9 and S. multivorum PW04-A6) were obtained, which the degradation rate of THPs can reach to 85.1%, 82.7% and 82.9% respectively. As was shown in the result of hereditary stability analysis, the three mutants all had stable genetic stability. [Conclusion] Through the isolation and mutation breeding, the TPHs degradation rate of the highly efficient THPs-degrading strain reached to 85.1%, increased by 48% compared with wild type strains. The highly efficient THPs-degrading strain can reduce the TPHs contents in the environment significantly and restore the oil-contaminated environment effectively.

Abstract:[Objective] The purpose of this study is to screen the fungus strain that can produce ochratoxin A (OTA). [Methods] To this end, 32 fungal samples in our laboratory were cultivated in CYA and YES media, and screened using the high performance liquid chromatography with fluorescence detection, then rescreened using high performance liquid chromatography-mass spectrometry; According to the colony morphology, mycelial and conidia morphology as well as nucleotide sequence analysis of ITS, β-Tubulin gene and Calmodulin gene, the target strain was identified. [Results] One strain which could grow well in CYA, YES and CA media at 25 °C was selected and named as strain 1062. Strain 1062 was identified as Aspergillus niger species by cultural and morphological characteristics and phylogenetic analysis based on ITS rDNA, β-tubulin and Calmodulin gene sequences. [Conclusion] The strain 1062 is A. niger which can produce OTA.

Abstract:[Objective] The aim of this study is to assess the effects of long-term (4 months) soil storage on the metabolic activity of soil microbial community. [Methods] Biolog? EcoPlateTM was used to test carbon source utilization patterns of the microbial communities in the arable and forest soils stored at 4 °C after air drying or at ?20 °C with field moisture, respectively. [Results] Compared with the fresh soil samples, the abilities of carbon source utilization of microbial communities in the stored soils were greatly reduced, with the microbial diversity index, evenness and Simpson index decreased as well. There was no significant difference in the influence on the abilities of carbon source utilization of microbial community between air dried samples and frozen samples. Two storage methods significantly decreased the metabolic activity of microbial community except for the metabolic activity of polymer-utilizing microbial group in air dried soil samples, with the reduction of 54.5%-99.8%. [Conclusion] Long-term storage of soil samples may lead to underestimation of the information about soil microbial community, and fresh soils are the best samples for exploring soil microbial metabolic activity.

Abstract:[Objective] The membrane proteins of Myxococcus xanthus, a model organism for studying prokaryotic development, remain an under-explored territory. [Methods] Putative outer membrane protein (OMP)-encoding ORFs were selected from Myxococcus xanthus genome using six computational algorithms. With lacZ as a reporter, we monitored the expression profiles of these genes during vegetative growth and development. [Results] Eleven putative OMPs have been identified based on bioinformatic analysis. Increased expression during development was found in two genes, MXAN3106 and MXAN3883, which were predicted to encode protein transporters of the secretin family and the fimbrial usher protein (FUP) family, respectively. The remaining nine genes that code for TonB-dependent receptors or efflux proteins exhibited a decreased expression or remained at a very low expression level after initiation of development. [Conclusion] Our data suggest that for M. xanthus, switching from growth to development is associated with a dramatic change in the expression pattern of membrane proteins.

Abstract:[Objective] In this study, ground phosphaterock was used as the undissolved phosphorus to select the high-efficient phosphate-solubilizing bacteria from the banana rhizosphere soil. [Methods] The methods of halo ring and Mo-Sb colorimetry were applied to isolate the phosphate-solubilizing bacteria. And a combination of morphologic alcharacteristics identification, physiological and biochemical test, 16S rRNA gene sequences analysis and phylogenic trees were employed to determine the genus of the phosphate-solubilizing bacteria. Various sources of carbon or nitrogen, the C/N value (40:1, 20:1, 8:1) and the pH value of culture medium which may affect the bacteria’s ability to dissolve the ground phosphate rock were studied with the single factor experimental method. [Results] Eight strains of phosphate-solubilizing bacteria (PSB) were isolated from the root soil, and three of them, B3-5-6, M-3-01, T1-4-01, were taken as representatives. The B3-5-6 was identified to be Bacillus aerophilus, M-3-01 Serratia nematodiphila and T1-4-01 Enterobacter asburiae. The phosphate-solubilizing ability of B3-5-6 and the pH of the culture medium was found to be linear negative correlated (|r|=0.949 66>0.735) and reached the extremely significant level. For strain B3-5-6, the phosphate-solubilizing ability was better when the carbon source was sucrose, nitrogen source was (NH4)2SO4 and C/N was 40:1. For strain T1-4-01, the phosphate-solubilizing ability was better when the carbon source was glucose, nitrogen source was (NH4)2SO4 and C/N was 20:1. For strain M-3-01, the phosphate-solubilizing ability was better when the carbon source was glucose, nitrogen source was (NH4)2SO4 and C/N was 20:1 for strain T1-4-01, the phosphate-solubilizing ability was better when the carbon source was lactose, nitrogen source was peptone and C/N was 20:1. The phosphate-solubilizing ability was raised 1.12 fold, 1.17 fold and 2.55 fold, respectively. [Conclusion] Various sources of carbon or nitrogen, and C/N could affect the phosphate-solubilizing ability of different strains. The phosphate-solubilizing ability of B3-5-6 and the pH of the culture medium was found to be linear negative correlated (|r|=0.949 66>0.735) and reached the extremely significant level. The phosphate-solubilizing mechanism of this strain needs to be furtherly investigated.

Abstract:[Objective] To isolate and screen actinomycetes with antimicrobial activity from Ginkgo biloba, and provide new resources for the application of actinomycetes in biological control. [Methods] The cultural method of plant tissue paste on medium were used to isolate actinomycetes. [Results] In total, we have isolated 156 endophytic actinomycetes from Ginkgo biloba. The fermentation broth of 47 strains could inhibit growth of the tested phant pathogenic fungi, and the strain KLBMP 5501 exhibited extensive antagonism on most of tested pathogens. Based on the morphological characteristics, cultural characteristics, physiological characteristics and 16S rRNA gene sequence similarity analysis, strain KLBMP 5501 was identified as Streptomyces violascens, a known species of Streptomyces. [Conclusion] Actinomycetes strains with high antimicrobial activity were obtained and showed potential for biological control of plant diseases. One of these strains, KLBMP 5501, was identified.

Abstract:[Objective] In recent years, there has been an increasing worldwide prevalence of bacterial resistance to a wide range of antibiotics, resulting in a focus of research interest in bacteriophage. Unfortunately, streptococcus suis (SS) bacteriophage is not easy to isolate, and the endolysin encoded by phage has been examined as a potential agent for SS control. [Methods] In this study, based on the analysis of genomic information of several streptococcus suis deposited in GenBank, we mined and analyzed one endolysin named Ly7917 encoded by a prophage harbored in Streptococcus suis serotype 7 (SS7) genome. The ly7917 gene was amplified by PCR using bacterial genome purified from a SS7 strain 7917 as template and then inserted into the pET28a(+) plasmid. The recombinant plasmid pET28a(+)-ly7917 was transformed into Escherichia coli DH5α, the sequencing of positive colony showed 100% homology with the target gene. The recombinant plasmid was then transformed into E. coli BL21 and induced with IPTG for expression. [Results] The result of plate analysis showed that Ly7917 has highly activity and can lysis Streptococcus suis serotype 2 strain HA9801. In addition, bacterial turbidity test showed that Streptococcus suis serotype 7, serotype 9, most of serotype 2 strains, Streptococcus equi subsp. zooepidemicus strain, Staphylococcus aureus (including Methicillin-resistant Staphylococcus aureus) were highly sensitive to Ly7917. [Conclusion] Effective and broad-spectrum characteristics of Ly7917 mined from prophage brings hope for mixed infection in clinical as an effective therapeutic.

Abstract:[Objective] To study the function of terC (SCO2366) in Streptomyces coelicolor M145. [Methods] Through knocking out the terC in S. coelicolor M145, we detected its effects on actinorhodin biosynthesis and mycelium development. [Results] After knocking out the terC in S. coelicolor M145, the synthesis of actinorhodin began earlier than the wild type strain, and the length of mutant’s mycelium got shorter. [Conclusion] terC in S. coelicolor M145 has negative effect on actinorhodin biosynthesis, meanwhile affects mycelium development.

Abstract:[Objective] To isolate and identify endophytic bacteria from the roots of Paeonia suffruticosa and evaluate antifungal activity of secondary metabolites of antagonistic strains in vitro. [Methods] The endophytic bacteria were screened against Botrytis paeoniae, Gloeosporium sp., Altenaria sp., Phyllosticta commonsii through the method of dual culture. The strains were indentified based on characteristics in morphology, physiology, biochemistry and phylogenetic analysis of 16S rRNA gene sequences. The lipopeptide biosynthetic genes fragments of antagonistic strains were amplified by polymerase chain reaction. The crude lipopeptides of strains were obtained through acid precipitate method. The inhibition ability of lipopeptides produced by antagonistic strains against pathogenic fungi was evaluated in vitro. [Results] The 62 endophytic bacterial isolates were isolated from the roots of Paeonia suffruticosa. The isolates Md31 and Md33 showed inhibitory activity against four pathogens. Md31 and Md33 were identified as Bacillus amyloliquefaciens. The genes fragments of bmyB, fenD, ituC, srfAA and srfAB were obtained in genomic DNA of the two strains. The crude lipopeptides prouduced by Md31 and Md33 were isolated from culture supernatants and exhibited inhibitory activity on mycelium growth of peony pathogens. [Conclusion] Two antagonistic B. amyloliquefaciens strains Md31 and Md33 were obtained, and their crude lipopeptides showed inhibitory activity against four peony pathogens in vitro, which will been provided a basis for the further development and application of peony endophytes.

Abstract:Cellulases can degrade cellulose and widely applied in bioremediation, food processing, chemical synthesis and other fields. Therefore, it is really significant to develop new types of cellulases that have high activity, broad substrate spectrum, high temperature and alkali resistance, and other anti-extreme-conditions capacity. The metagenomic technology focuses on the sum of microbial genomes in environmental samples, avoiding traditional process of microbial isolation and culture, and provides a new technology for the development and utilization of genetic resources. Combined with our own findings, this paper summarizes the strategies of gaining cellulases by use of metagenomic technology, and highlights advances in studying cellulases from animal gastrointestinal tract, soil and other environment with metagenomics.

Abstract:The secretome is a group of proteins secreted by cells and/or tissues at a given time and under a given condition. Most phytopathogenic fungi can secrete many proteins and metabolites during the plant-fungi interaction, and the secreted proteins and metabolites play important roles at different infection stages of fungal penetration, colonization, and lesion formation. In this review, we summarized recent advances in biological functions of secreted proteins in fungal pathogenicity, the secretome of important plant pathogenic fungi, and bioinformatics prediction of fungal secretomes, which will help to understand the mechanisms involved in fungal pathogenesis.

Abstract:Confocal laser scanning microscope (CLSM or LSCM) offers higher resolution than traditional optical microscopy due to use of laser illumination source, pinhole spatial filter and point scanning technology. In combination with other biological technologies, CLSM enables the qualitative and quantitative characterization of various biochemical ingredient in situ. As CLSM is a valuable tool for observing living cells, obtaining scan-images of thick specimens at various depths and three-dimensional reconstructions, it has great application in the research of antimicrobial and anti-biofilm. This paper concerns the applications of CLSM in the cellular distribution of microbicides and its effect on cell membrane, metabolic pathways, as well as the formation and structure of biofilm.

Abstract:Lignin as the most abundant aromatic compounds, its decomposition is closely related to the carbon cycle. The bio-conversion of lignocellulose to glucose is an important part of second generation biofuel production, but the resistance of lignin to breakdown is a bottleneck in this process, hence there is considerable interest in the microbial breakdown of lignin. The degradation of lignin by fungi has been well studied, but it is still not clear in bacteria. Recently, many researchers focus on the lignin degradation by bacteria, because a wide range of growth conditions and good environment adaptability for bacteria. In addition, the rapidly development of omics technique such as gemome, transcriptome, proteome and metabolomics promoted the study on the bacterial degradation of lignin. This review introduced the recent research about the diversity of bacteria in lignin degradation, the lignin metabolism pathway and involved enzymes.

Abstract:Phosphorylation is one of the most common post-translational modifications of viral proteins, which plays important roles in viral life cycle. The dynamic activities of viral proteins can be regulated by phosphorylation and dephosphorylation, which affect the cellular signal transduction for regulating some metabolism. Additionally, phosphorylation of viral proteins is involved in regulation of a series of viral metabolism, such as DNA replication, viral proliferation, assembly of virion and so on. Meanwhile, the phosphorylation of viral proteins has an effect on cellular signal transduction of hosts to inhibit DNA replication and gene expression of hosts. The phosphorylation sites, biological function and the molecular mechanism of its formation of various viral proteins were summarized in this review, which is helpful for controlling viral spread and development of new drug.

Abstract:Nitrogen is one of the most important substances on global biogeochemical processes which are driven by microorganisms. Due to anthropogenic disturbance in recent years, the nitrogen flux has increased and therefore disturbed the balance of nitrogen cycle and the community characteristics of functional microbes. Excessive activated nitrogen discharged into water body has lead to eutrophication which impairs the ecological function of river and coastal zone adjacent to estuary. The nitrogen transformation and removal by microorganism plays a vital role in improving river ecosystem, which is connecting link between terrestrial and marine ecosystems. This review focuses on ecological functions and community patterns of ammonia-oxidizing prokaryotes, nitrite-oxidizing bacteria, denitrifying bacteria and anaerobic ammonia oxidation bacteria in river sediment. Characteristics of community response to different environmental factors (e.g. ammonia, nitrate, dissolved oxygen, salinity and seasonal change), river management practices and effluent from wastewater treatment plant are reviewed. Further approach to a better understanding on ecological function of nitrogen cycling microbes in river ecosystem are suggested, including contribution of microbes to nitrogen cycle in urban rivers and development of bioremediation technology.

Abstract:As the long-time and unscientific use of biocide in power plant’s Cycling Cooling Water System, bacterial resistance to?biocides is becoming stronger and stronger. Research on the resistant mechanism has certain theoretical value and practical value. This paper reviews the recent research progress about the sulfate-reducing bacterial resistance and resistance mechanisms to various biocides. Main content: the concept of bacterial resistance to biocide, the status quo of bacterial drug-resistant, biocide’s bactericidal mechanisms and bacterial resistant mechanism.

Abstract:Along with the restriction and prohibition of use of highly toxic organophosphorus pesticides, the market share of the low toxic organophosphours pesticides represented by chlorpyrifos has increased in the recent years. However, the use of chlorpyrifos has led to generation of 3,5,6-trichloro-2-pyridinol (TCP) in the environment, because TCP is the main intermediate metabolite of chlorpyrifos and chlorpyrifos-methyl. It is more water soluble, more mobile in soil and more leachable into groundwater and surface water, which causes widespread contamination in soils and aquatic environment. TCP released into the environment not only inhibits the biodegradation of TCP and its parent compound chlorpyrifos and chlorpyrifos-methyl, but also inhibits the biodegradation of other organic pollutants and therefore further increases the residual of TCP and other organic pollutants. In this article, we summarize the chemical structure of TCP and its parent compound, the ecological toxicity of TCP, the diversity of microorganisms capable of degrading TCP, the latest research progress of the biodegradation of TCP, in order to provide the guidance for the economically feasible bioremediation strategy in chlorpyrifos and TCP contaminated area.

Abstract:[Objective] In order to establish an efficient cross breeding method assisted by molecular markers of Volvariella volvacea and apply it to monospore cross breeding for the cold-tolerant and high-yield Volvariella volvacea strain. [Methods] In this study, the high-yield strain Pingyou No. 1 tested by cultivation experiment and the cold-tolerant strain VH3 were chosen as crossing parent strains. Then used the molecular marker of mating-type genes in Volvariella volvacea to verify mating-type of Volvariella volvacea monospore strain and completed the cross breeding. At last part of the cold-intolerant hybrids were eliminated before cultivation experiment using techniques of fast screening of the cold-tolerant Volvariella volvacea strain and identification of the hybrid strains. [Results] The result of cultivation experiment showed that the strain Pingyou No. 1 got the highest biological efficiency, which would be chosen as the high-yield parent strain. The 172 cold-tolerant hybrid strains were screened out from the original 496 possible hybrid strains so that the workload of cultivation experiment in the late would get a 65% reduction. The result of hybrid strains cultivation experiment showed that VV093 got higher biological efficiency than Pingyou No. 1 or VH3 at 28 °C. [Conclusion] Establishment of an efficient cross breeding method assisted by molecular markers of Volvariella volvacea included selection of parental strains, identification of monospore strains’ mating-type genes, monospore cross breeding, screening and identification of possible hybrid strains, and it was applied to monospore cross breeding for the cold-tolerant and high-yield Volvariella volvacea strain successfully.

Abstract:[Objective] To establish a rapid, sensitive and effective method for screening of the fungi producing extracellular cellulases with high β-glucosidase activity. [Methods] Iodine vapor staining was used to replace Congo red or iodine dip dyeing in the screening methods of extracellular cellulase producing fungi by agarose plates complemented with avicel or CMC in order to reduce the consumption and pollution of gram’s iodine, and the screening method of β-glucosidase producing fungi by the agarose plates complemented with 4-Nitrophenyl-β-D-glucopyranoside (pNPG) was established. Finally, these two methods were used successively to screening the fungi producing extracellular cellulases with high β-glucosidase activity. [Results] The screening methods of both the avicel or CMC agarose plates with iodine vapor staining and the pNPG agarose plates were established successfully, and used successively to screening 8 strains of extracellular cellulase producing fungi with level ++++ cellulase activity out of 56 fungus strains, and from which 4 strains of extracellular cellulase producing fungi with high β-glucosidase activity were screening out. [Conclusion] It could be concluded that the method of avicel or CMC agarose plate with iodine vapor staining integrated with pNPG agarose plate assay would be a rapid, sensitive and effective method for screening of the fungi producing extracellular cellulases with high β-glucosidase activity.