He M.,Xiamen University |
He M.,Guangdong Institute of Microbiology |
Wang W.-X.,Xiamen University |
Wang W.-X.,Hong Kong University of Science and Technology
Food and Chemical Toxicology | Year: 2013
We conducted a large scale investigation of the bioaccessibility of 12 trace elements from 11 marine mollusc species (scallop, oyster, clam, abalone, snail, and mussel) collected from five locations in Chinese coastal waters. The bioaccessibility of all the 12 trace elements was generally high, with the average values ranging from 42.5% to 90.7%. The highest bioaccessibility was observed for As, Cu, Ni and Se, and the lowest for Fe, Co and Pb. Steaming decreased the bioaccessibility of all 12 trace elements and thus diminished their risks. No correlation was observed between the bioaccessibility and the total concentration of the 12 elements. However, there was a significant correlation between the bioaccessibility of the 12 elements and their subcellular distribution. For most trace elements, a significantly negative relationship was demonstrated between the bioaccessibility and the elemental partitioning in the metal-rich granule fraction or in the cellular debris fraction, and a significantly positive correlation was observed between the bioaccessibility and the elemental partitioning in the heat-stable protein fraction and in the trophically available fraction. Hence, the elemental subcellular distribution, especially the elemental partitioning in the trophically available fraction, might be a good predictor of the bioaccessibility and risks of trace elements in molluscs. © 2013 Elsevier Ltd.
Zhang X.,Guangdong Institute of Microbiology
Wei sheng wu xue bao = Acta microbiologica Sinica | Year: 2011
Bacteroidales has been proposed as a fecal pollution indicator. microbial source tracking (MST) based on Bacteroidales host-specific gene markers has recently been applied in the fecal pollution identification, which does not require culturing the fecal pollution indicator organisms. This method needs to design specific primers. The primers are designed based on Bacteroidales specific 16S rRNA gene. Once a pair of specific primers was amplified, the fecal pollution can be identified. In this paper, the progress of specific primers of Bacteroidales in human, swine, ruminant feces were reviewed and discussed. The advantages and disadvantages were put forward. Future researchers should be focused on the new biological markers and the combination of different MST methods.
Xu M.,Guangdong Institute of Microbiology
Wei sheng wu xue bao = Acta microbiologica Sinica | Year: 2010
Microbial eco-systems metabolic networks (MEMNs) are ubiquitous in nature and are the major drivers of biosphere processes. Here we try to define MEMNs and describe their significances in microbial ecology studies. We also review recent progresses and approaches of MEMNs including highlights of the major discoveries in these studies based on mixed-cultures, high-throughput sequencing and microarray data, computational approaches, and metabolic reconstruction. In addition, we discuss the potential shortcomings of current approaches and propose that the time is ripe to study the energy-based microbial metabolic networks in bioremediation systems, especially under the anaerobic conditions, which will reclaim the wastes to resources.
Chen X.,Guangdong Institute of Microbiology
Wei sheng wu xue bao = Acta microbiologica Sinica | Year: 2011
Zero-valent iron (Fe(0)) is very effective for the transformation of a wide variety of common environmental contaminants. No contaminant mineralization happened only by Fe(0) corrosion, but the pollutants would be completely detoxified and degraded by the integrated microbial-Fe(0) treatment, which represent a new generation of environmental remediation technologies. In this paper, the mechanism, microbial diversity and application of the integrated microbial-Fe(0) treatment processes were reviewed. In addition, we also discussed the main problems and challenges in this filed.
Chen M.-J.,Guangdong Institute of Microbiology |
Shi Q.-S.,Guangdong Institute of Microbiology
ACS Sustainable Chemistry and Engineering | Year: 2015
The major challenges for directly converting lignocellulosic biomass into available materials in place of synthetic polymer materials are the complex chemical-physical structure and the narrow processing windows of the resources. In the present study, homogeneous chemical modification of sugarcane bagasse with phthalic anhydride was taken to be an improved strategy to meet the challenges. FT-IR and liquid-state NMR spectra confirmed the chemical structure of the sugarcane bagasse phthalates. Sugarcane bagasse phthalates with weight percentage gain higher than 32.9% were readily dissolved in organic solvents, and film materials were prepared by solution casting from the sugarcane bagasse phthalates. Thermogravimetric analysis and differential scanning calorimetry was applied to study the thermal behaviors of the sugarcane bagasse phthalates. Scanning electron microscope, atomic force microscopy and tensile testing were applied to study the morphologies and mechanical properties of the films. The results indicated that sugarcane bagasse was plasticized by homogeneous chemical modification with phthalic anhydride. © 2015 American Chemical Society.
Sang Z.G.,Guangdong Institute of Microbiology
Zhong yao cai = Zhongyaocai = Journal of Chinese medicinal materials | Year: 2011
To study the secondary metabolites of Coriolopsis sp. G066. The compounds were isolated by various chromatographic methods (silica gel, reverse silica gel, Sephadex LH-20, preparative TLC and so on). Their structures were determined by extensive analysis of their spectroscopic data as well as by comparison with literature reports. Six compounds were isolated and identified as diaporthein A(1), tyrosol(2), eburicoic acid(3), ergosterol(4), ergosterol peroxide(5) and cerevisterol (6). All the compounds are isolated from the genus for the first time.
He Z.,University of Oklahoma |
Xu M.,University of Oklahoma |
Xu M.,Guangdong Institute of Microbiology |
Deng Y.,University of Oklahoma |
And 7 more authors.
Ecology Letters | Year: 2010
Understanding the responses of biological communities to elevated CO2 (eCO2) is a central issue in ecology, but little is known about the influence of eCO2 on the structure and functioning (and consequent feedbacks to plant productivity) of the belowground microbial community. Here, using metagenomic technologies, we showed that 10 years of field exposure of a grassland ecosystem to eCO2 dramatically altered the structure and functional potential of soil microbial communities. Total microbial and bacterial biomass were significantly increased at eCO2, but fungal biomass was unaffected. The structure of microbial communities was markedly different between ambient CO2 (aCO2) and eCO2 as indicated by detrended correspondence analysis (DCA) of gene-based pyrosequencing data and functional gene array data. While the abundance of genes involved in decomposing recalcitrant C remained unchanged, those involved in labile C degradation and C and N fixation were significantly increased under eCO2. Changes in microbial structure were significantly correlated with soil C and N contents and plant productivity. This study provides insights into potential activity of microbial community and associated feedback responses of terrestrial ecosystems to eCO2. © 2010 Blackwell Publishing Ltd/CNRS.
Zhang L.,Guangdong Institute of Microbiology
Zhong yao cai = Zhongyaocai = Journal of Chinese medicinal materials | Year: 2012
To study the secondary metabolites of the marine fungus Penicillium sp. FS60 from the South China Sea and their cytotoxicities. The compounds were isolated from the culture of strain FS60 by various chromatographic methods (silica gel, reverse silica gel, Sephadex-LH20, preparative TLC, HPLC and PTLC) and recrystallization. Their structures were identified by extensive analysis of their spectroscopic data. Compounds were tested for their cytotoxicities against SF-268, MCF-7, and NCI-H460 cell lines by SRB method. While, Compounds were tested for their antibacterial activities against S. aureus, E. coli and P. aeruginosa. Seven compounds were isolated from the culture and identified as methyl 2,4-dihydroxy-3,5,6-trimethylbenzoate (1), 4-hydroxyacetophenone (2), 5-hydroxymethyl-furoic acid (3), isochromophilones VIII (4), ergosterol (5), ergosterol peroxide (6), and cerevisterol (7). Compound 1 is isolated from the genus Penicillium for the first time. Compound 3 is demonstrated to have significant inhibition against S. aureus and P. aeruginosa. Compound 4 is demonstrated to have significant inhibition against the three cell lines.
Dong X.,Guangdong Institute of Microbiology
Wei sheng wu xue bao = Acta microbiologica Sinica | Year: 2013
This study aimed to detect and quantify Cronobacter in 300 powdered milk samples and 50 non-powdered milk samples. Totally, 24 Cronobacter (formerly Enterobacter sakazakii) strains isolated from powdered milk and other foods were identified and confirmed. Cronobacter strains were detected quantitatively using most probable number (MPN) method and molecular detection method. We identified 24 Cronobacter strains using biochemical patterns, including indole production and dulcitol, malonate, melezitose, turanose, and myo-Inositol utilization. Of the 24 strains, their 16S rRNA genes were sequenced, and constructed phylogenetic tree by N-J (Neighbour-Joining) with the 16S rRNA gene sequences of 17 identified Cronobacter strains and 10 non-Cronobacter strains. Quantitative detection showed that Cronobacter strains were detected in 23 out of 350 samples yielding 6.6% detection rate. Twenty-four Cronobacter strains were isolated from 23 samples and the Cronobacter was more than 100 MPN/100g in 4 samples out of 23 samples. The 24 Cronobacter spp. isolates strains were identified and confirmed, including 19 Cronobacter sakazakii strains, 2 C. malonaticus strains, 2 C. dubliensis subsp. lactaridi strains, and 1 C. muytjensii strain. The combination of molecular detection method and most probable number (MPN) method could be suitable for the detection of Cronobacter in powdered milk, with low rate of contamination and high demand of quantitative detection. 24 isolated strains were confirmed and identified by biochemical patterns and molecular technology, and C. sakazakii could be the dominant species. The problem of Cronobacter in powdered milk should be a hidden danger to nurseling, and should catch the government and consumer's attention.
Li Z.,Guangdong Institute of Microbiology |
Zhu H.,Guangdong Institute of Microbiology
International Journal of Systematic and Evolutionary Microbiology | Year: 2012
A Gram-reaction-negative bacterial strain, designated GIMN1.005T, was isolated from a forest soil sample in Vietnam. The isolate was yellow-pigmented, strictly aerobic, and unable to grow below 5 °C or above 37 °C and in the presence of more than 2.0% NaCl. Cells were non-motile, non-gliding and non-spore-forming. The yellow pigment was of the flexirubin type, non-diffusible and non-fluorescent. Analysis of 16S rRNA gene sequences showed that strain GIMN1.005Toccupied a distinct lineage within the genus Chryseobacterium, with sequence similarity values of 98.6, 98.5 and 98.3% to Chryseobacterium aquifrigidense KCTC 12894T, Chryseobacterium jejuense KACC 12501Tand Chryseobacterium indologenes GIFU 1347T, respectively. The level of DNA-DNA relatedness between strain GIMN1.005Tand C. jejuense KACC 12501Twas, 30 %. The DNA G+C content of strain GIMN1.005Twas 42.1 mol%. The predominant cellular fatty acids were iso-C15: 0, iso-C17: 03-OH and summed feature 3 (C16: 1ω7c and/or C16: 1ω6c); menaquinone 6 (MK-6) was the sole respiratory quinone. On the basis of phenotypic properties and phylogenetic distinctiveness, strain GIMN1.005Tis considered to represent a novel species of the genus Chryseobacterium, for which the name Chryseobacterium vietnamense sp. nov. is proposed. The type strain is GIMN1.005T(=CCTCC M 209230T=NRRL B-59550T). © 2012 IUMS.