scholarly journals Degradation of 2,3,7,8-TCDD by a consortium of bacterial strains isolated from heavil herbicide/dioxin contaminated soil in Bienhoa airbase

2020 ◽  
Vol 16 (4) ◽  
pp. 777-784
Author(s):  
Pham Quang Huy ◽  
Nguyen Kim Thoa ◽  
Dang Thi Cam Ha
Keyword(s):  
Contaminated Soil ◽  
Large Scale ◽  
Morphological Characteristics ◽  
Bacterial Consortium ◽  
Soil Extract ◽  
High Ratio ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Agrobacterium Strain ◽  
Microbial Strains

From two different soil sources in Bienhoa airbase (heavy herbicide/dioxin contaminated West-South region and bioremediated cell), five microbial strains were isolated and their 2,3,7,8-TCDD biodegrability in consortium was investigated. Based on the colony and cell morphological characteristics as well as 16S rRNA gene sequences, these strains were classified into 5 genera, including Methylobacterium (strain BHBi1), Hydrocarboniphaga (strain BHBi4), Agrobacterium (strain BHBi5), Bosea (strain BHBi7) and Microbacterium (strain BH09). Two strains BHBi7 and BHBi4 were the first representatives of the genera Bosea and Hydrocarboniphaga that were isolated from heavyly herbicide/dioxin contaminated soil. All five strains were able to grow well in mineral salt medium (MSM) supplemented with soil extract (SE) containing 2,3,7,8-TCDD (this congener is the main soil total compound toxicity) and other congeners, including PCDDs, PCDFs, 2,4,5-T, 2,4-D, PAHs and their intermediates. This microbial consortium degraded 2,537.34 ngTEQ/kg of 2,3,7,8-TCDD congener in soil, equivalent to 59.1% lost of total toxicity in comparison to the control without bacterial seeding (4,294.12 ng TEQ/kg). Such a high ratio of dioxin degradation by a bacterial consortium was reported here for the first time, contributing more evidences for convincing the successful dioxin bioremediation of “Active Landfill” technology at large scale in Z1 area at Bienhoa airbase, Dongnai, Vietnam.

scholarly journals Characterization, Phylogenetic Analyses, and Pathogenicity of Enterobacter cloacae on Rice Seedlings in Heilongjiang Province, China

Plant Disease ◽  
2020 ◽  
Vol 104 (6) ◽  
pp. 1601-1609
Author(s):  
Peng Cao ◽  
Chenxu Li ◽  
Kefei Tan ◽  
Chuanzeng Liu ◽  
Xi Xu ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Phylogenetic Analyses ◽  
Morphological Characteristics ◽  
Enterobacter Cloacae ◽  
Rrna Gene ◽  
Bacterial Disease ◽  
Heilongjiang Province ◽  
Rice Seedlings ◽  
Bacterial Strains ◽  
Gene Sequences

Rice is used as a staple food in different areas of world, especially in China. In recent years, rice seedlings have been affected seriously by symptoms resembling bacterial palea browning (BPB) in Heilongjiang Province. To isolate and identify the pathogenic bacteria responsible for the disease, 40 bacterial strains were isolated from diseased rice seedlings collected from the four major accumulative-temperature zones of rice fields cultivated in Heilongjiang Province, and these were identified as 13 species based on morphological characteristics and 16S ribosomal RNA (rRNA) gene sequences. Inoculation of all the isolates on healthy rice seedlings showed that the nine Enterobacter cloacae isolates were the pathogens causing typical symptoms of BPB, including yellowing to pale browning, stunting, withering, drying, and death. Moreover, the nine E. cloacae isolates could also cause symptoms of bacterial disease on the seedlings of soybean (Glycine max), maize (Zea mays L.), and tomato (Solanum lycopersicum). Phylogenetic analysis based on the 16S rRNA gene sequences and phenotypic and biochemical characteristics indicated that these nine pathogenic isolates were E. cloacae. In addition, analysis of the sequences of four housekeeping genes (rpoB, gyrB, infB, and atpD) from the selected strain SD4L also assigned the strain to E. cloacae. Therefore, E. cloacae is the pathogen causing disease of rice seedlings in Heilongjiang Province, which we propose to classify as a form of BPB. To the best of our knowledge, this is the first study to identify E. cloacae as a causal agent of BPB in rice.

scholarly journals Integrated Genomic and Metabolomic Approach to the Discovery of Potential Anti-Quorum Sensing Natural Products from Microbes Associated with Marine Samples from Singapore

Marine Drugs ◽  
2019 ◽  
Vol 17 (1) ◽  
pp. 72 ◽  
Author(s):  
Ji Ong ◽  
Hui Goh ◽  
Swee Lim ◽  
Li Pang ◽  
Joyce Chin ◽  
...  
Keyword(s):  
Drug Discovery ◽  
Quorum Sensing ◽  
Large Scale ◽  
Marine Ecosystem ◽  
Gene Clusters ◽  
Integrated Approach ◽  
Rrna Gene ◽  
Dependent Manner ◽  
Bacterial Strains ◽  
Reporter System

With 70% of the Earth’s surface covered in water, the marine ecosystem offers immense opportunities for drug discovery and development. Due to the decreasing rate of novel natural product discovery from terrestrial sources in recent years, many researchers are beginning to look seaward for breakthroughs in new therapeutic agents. As part of an ongoing marine drug discovery programme in Singapore, an integrated approach of combining metabolomic and genomic techniques were initiated for uncovering novel anti-quorum sensing molecules from bacteria associated with subtidal samples collected in the Singapore Strait. Based on the culture-dependent method, a total of 102 marine bacteria strains were isolated and the identities of selected strains were established based on their 16S rRNA gene sequences. About 5% of the marine bacterial organic extracts showed quorum sensing inhibitory (QSI) activity in a dose-dependent manner based on the Pseudomonas aeruginosa QS reporter system. In addition, the extracts were subjected to mass spectrometry-based molecular networking and the genome of selected strains were analysed for known as well as new biosynthetic gene clusters. This study revealed that using integrated techniques, coupled with biological assays, can provide an effective and rapid prioritization of marine bacterial strains for downstream large-scale culturing for the purpose of isolation and structural elucidation of novel bioactive compounds.

Assessment of zinc solubilization potential of zinc-resistant Pseudomonas oleovorans strain ZSB13 isolated from contaminated soil

2023 ◽  
Vol 83 ◽  
Author(s):  
H. F. Rehman ◽  
A. Ashraf ◽  
S. Muzammil ◽  
M. H. Siddique ◽  
T. Ali
Keyword(s):  
Contaminated Soil ◽  
Bacterial Strain ◽  
Bacterial Species ◽  
Resistant Bacteria ◽  
Zn Deficiency ◽  
Rrna Gene ◽  
Growth Enhancement ◽  
Pseudomonas Oleovorans ◽  
Human Beings ◽  
Bacterial Strains

Abstract Zinc is an essential micronutrient that is required for optimum plant growth. It is present in soil in insoluble forms. Bacterial solubilization of soil unavailable form of Zn into available form, is an emerging approach to alleviate the Zn deficiency for plants and human beings. Zinc solubilizing bacteria (ZSB) could be a substitute for chemical Zn fertilizer. The present study aimed to isolate and characterize bacterial species from the contaminated soil and evaluate their Zn solubilizing potential. Zn resistant bacteria were isolated and evaluated for their MIC against Zn. Among the 13 isolated bacterial strains ZSB13 showed maximum MIC value upto 30mM/L. The bacterial strain with the highest resistance against Zn was selected for further analysis. Molecular characterization of ZSB13 was performed by 16S rRNA gene amplification which confirmed it as Pseudomonas oleovorans. Zn solubilization was determined through plate assay and broth medium. Four insoluble salts (zinc oxide (ZnO), zinc carbonate (ZnCO3), zinc sulphite (ZnS) and zinc phosphate (Zn3(PO4)2) were used for solubilization assay. Our results shows 11 mm clear halo zone on agar plates amended with ZnO. Likewise, ZSB13 showed significant release of Zn in broth amended with ZnCO3 (17 and 16.8 ppm) and ZnO (18.2 ppm). Furthermore, Zn resistance genes czcD was also enriched in ZSB13. In our study, bacterial strain comprising Zn solubilization potential has been isolated that could be further used for the growth enhancement of crops.

scholarly journals Diversity and antibacterial activity of fungal endophytes from Eucalyptus exserta

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ziling Mao ◽  
Weihao Zhang ◽  
Chunyin Wu ◽  
Hao Feng ◽  
Yuanhang Peng ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Endophytic Fungi ◽  
Ralstonia Solanacearum ◽  
Large Scale ◽  
Antimicrobial Agents ◽  
Fungal Endophytes ◽  
Morphological Characteristics ◽  
Plant Diseases ◽  
Rrna Gene ◽  
Fungal Isolates

Abstract Background Eucalyptus bacterial wilt caused by Ralstonia solanacearum is an important eucalyptus disease. Endophytic fungi, an important source of natural active substances, provide a new breakthrough for the control of plant diseases. Results In the present study, 80 endophytic fungal isolates were obtained from the healthy branches and fruits of Eucalyptus exserta. Fifteen distinct isolates (MK120854-MK120868) were selected for further taxonomic identification through morphological trait assessments and internal transcribed spacer (ITS) region-rRNA gene sequence analysis. Thirteen genera, namely, Phyllosticta, Penicillium, Eutypella, Purpureocillium, Talaromyces, Lophiostoma, Cladosporium, Pestalotiopsis, Chaetomium, Fusarium, Gongronella, Scedosporium and Pseudallescheria, were identified on the basis of their morphological characteristics. Members of the genus Phyllosticta were the primary isolates, with a colonization frequency (CF) of 27.5 %. Most of the fungal isolates displayed antibacterial activity. The crude extracts obtained from Lophiostoma sp. Eef-7, Pestalotiopsis sp. Eef-9 and Chaetomium sp. Eef-10 exhibited strong inhibition on the test bacteria, and Lophiostoma sp. Eef-7 was further cultured on a large scale. Three known compounds, scorpinone (1), 5-deoxybostrycoidin (2) and 4-methyl-5,6-dihydro-2 H-pyran-2-one (3), were isolated from the endophytic fungus Lophiostoma sp. Eef-7 associated with E. exserta. The structures of these compounds were elucidated by analysis of 1D and 2D NMR and HR-ESI-MS spectra and a comparison of their spectral data with published values. Compounds 1 and 2 showed weak antimicrobial activity against Ralstonia solanacearum. Conclusions Endophytic fungi from Eucalyptus exserta may represent alternative sources of antimicrobial agents. Lophiostoma sp. Eef-7 can produce 2-azaanthraquinone derivatives and shows weak antibacterial activity against Ralstonia solanacearum.

scholarly journals Biodecolorization of Azo Dye Mixture (Remazol Brilliant Violet 5r and Reactive Red 120) by Indigenous Bacterial Consortium Obtained From Dye Contaminated Soil

2021 ◽  
Author(s):  
R Rajendran ◽  
S Kiruthika ◽  
P Saranya ◽  
Arunkumar Mohan ◽  
C V Vaishali
Keyword(s):  
Removal Efficiency ◽  
Contaminated Soil ◽  
Nitrogen Sources ◽  
Enterobacter Cloacae ◽  
Bacterial Consortium ◽  
Rrna Gene ◽  
Carbon And Nitrogen Sources ◽  
Carbon And Nitrogen ◽  
Reactive Red 120 ◽  
Remazol Brilliant Violet 5R

Abstract Discharge of the untreated wastewater containing dyestuff into the surrounding aquatic environment is of significant environmental concern. These dying effluents not only change the color of water bodies but also has many unfavorable conditions and release toxic by-products, which are mutagenic, carcinogenic, and hazardous to different life forms. The present study investigated the biodegradation and removal of dye mixture (Remazol Brilliant violet 5R and Reactive Red 120) using a new bacterial consortium isolated from dye contaminated soil. Among the total 15 isolates screened, the two most efficient bacterial species (SS07 and SS09) were selected and identified as Enterobacter cloacae (MT573884) and Achromobacter pulmonis (MT573885) through biochemical assays and 16S rRNA gene sequencing. The removal efficiency of dye mixture by Enterobacter cloacae and Achromobacter pulmonis at an initial concentration of 100 mg L− 1 was 82.78 and 84.96%, discretely. The bacterial consortium was developed using selected isolates, and the optimum conditions for the removal of dyes were investigated by studying the effects of pH, temperature, carbon and nitrogen sources, dye concentration, and inoculum size. The maximum decolorization efficiency was achieved at pH, 7; temperature, 37°C; dye concentration, 100 ppm; and initial inoculum concentration, 0.5 ml, respectively. Mannitol and Ammonium sulfate was identified as the most suitable carbon and nitrogen sources for better bacterial growth and decolorization. The maximum removal efficiency of 91.3% achieved at the optimal conditions after 72 h of incubation. Decolorization of azo dyestuff by the developed microbial consortia conforms to the zero-order reaction kinetics model. Consortia of Enterobacter cloacae and Achromobacter pulmonis was established as an effective decolorizer for the Remazol Brilliant violet 5R and Reactive Red 120 dye mixture with > 90% color removal.

scholarly journals New Strains of Bacteria that Degrade Aromatic Compounds Act as Antagonists of Highly Active Phytopathogens

Proceedings ◽  
2020 ◽  
Vol 66 (1) ◽  
pp. 2
Author(s):  
Tatiana O. Anokhina ◽  
Tatiana Z. Esikova ◽  
Tatiana N. Abashina ◽  
Nataliya E. Suzina ◽  
Inna P. Solyanikova
Keyword(s):  
Aromatic Compounds ◽  
Crop Yields ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Antifungal Effect ◽  
Highly Active ◽  
Benzoate Degradation ◽  
Development Cycle ◽  
Microbial Strains ◽  
Fungal Phytopathogens

The intensive development of agriculture leads to the depletion of land and a decrease in crop yields and in plant resistance to diseases. A large number of fertilizers and pesticides are currently used to solve these problems. Chemicals can enter the soil and penetrate into the groundwater and agricultural plants. Therefore, the primary task is to intensify agricultural production without causing additional damage to the environment. This problem can be partially solved using microorganisms with target properties. Microorganisms that combine several useful traits are especially valuable. The aim of this work was to search for new microbial strains that possess a complex, technologically significant potential, such as increasing the bioavailability of nutrients, phytostimulation, antifungal effect and degradation of pesticide residues and other xenobiotics. Few isolated Bacillus and Pseudomonas strains were characterized by high activity against fungal phytopathogens. One of the bacterial strains identified as Bacillus sp. on the basis of the 16S rRNA gene sequence was characterized by an unusual cellular morphology and development cycle, significantly different from all previously described bacteria of this genus. All isolated bacteria are capable of benzoate degradation, as a sign of the ability to degrade aromatic compounds. Isolated strains were shown to be perspective agents in biotechnologies.

scholarly journals Cupriavidus pampae sp. nov., a novel herbicide-degrading bacterium isolated from agricultural soil

2010 ◽  
Vol 60 (11) ◽  
pp. 2606-2612 ◽  
Author(s):  
Virginia Cuadrado ◽  
Margarita Gomila ◽  
Luciano Merini ◽  
Ana M. Giulietti ◽  
Edward R. B. Moore
Keyword(s):  
Agricultural Soil ◽  
Bacterial Consortium ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Systematic Analysis ◽  
Hybridization Data ◽  
Degrading Bacterium ◽  
History Of ◽  
Pampa Region ◽  
Herbicide Use

A bacterial consortium able to degrade the herbicide 4-(2,4-dichlorophenoxy) butyric acid (2,4-DB) was obtained from an agricultural soil of the Argentinean Humid Pampa region which has a history of long-term herbicide use. Four bacterial strains were isolated from the consortium and identified as members of the genera Cupriavidus, Labrys and Pseudomonas. A polyphasic systematic analysis was carried out on strain CPDB6T, the member of the 2,4-DB-degrading consortium able to degrade 2,4-DB as a sole carbon and energy source. The Gram-negative, rod-shaped, motile, non-sporulating, non-fermenting bacterium was shown to belong to the genus Cupriavidus on the basis of 16S rRNA gene sequence analyses. Strain CPDB6T did not reduce nitrate, which differentiated it from the type species of the genus, Cupriavidus necator; it did not grow in 0.5–4.5 % NaCl, although most species of Cupriavidus are able to grow at NaCl concentrations as high as 1.5 %; and it was able to deamidate acetamide, which differentiated it from all other species of Cupriavidus. DNA–DNA hybridization data revealed low levels of genomic DNA similarity (less than 30 %) between strain CPDB6T and the type strains of Cupriavidus species with validly published names. The major cellular fatty acids detected were cis-9-hexadecenoic (16 : 1ω7c) and hexadecanoic (16 : 0) acids. On the basis of phenotypic and genotypic characterizations, strain CPDB6T was recognized as a representative of a novel species within the genus Cupriavidus. The name Cupriavidus pampae sp. nov. is proposed, with strain CPDB6T (=CCUG 55948T=CCM-A-29:1289T) as the type strain.

scholarly journals ISOLATION AND SELECTION OF INDIGENOUS ANTIFUNGAL MICROORGANISMS AGAINST PATHOGENIC FUNGI OF PEPPER PLANT IN TAY NGUYEN

2018 ◽  
Vol 16 (2) ◽  
pp. 385-392
Author(s):  
Pham Thi Thuy Hoai ◽  
Ton That Huu Dat ◽  
Tran Thi Hong ◽  
Nguyen Thi Kim Cuc ◽  
Tran Dinh Man ◽  
...  
Keyword(s):  
Fungal Pathogens ◽  
Rapid Development ◽  
Control Plant ◽  
Morphological Characteristics ◽  
Pathogenic Fungi ◽  
Plant Diseases ◽  
Rrna Gene ◽  
Pepper Plant ◽  
Bacterial Strains ◽  
Genus Streptomyces

The pathogenic fungi often cause huge impacts on agricultural crops, and occupy over 80% of plant diseases. Fusarium oxysporum and Rhizoctonia solani are fungal pathogens that can lead to rapid development of plant diseases on important crops in Tay Nguyen (e.g., pepper, coffee, rubber, cashew). Therefore, the study of microorganisms with bioactivity against these pathogens is essential to control plant diseases. In this study, we isolated microorganisms from rhizospheres of pepper in Tay Nguyen and screened beneficial microbes against two pathogenic fungi using agar well diffusion assay. Obtained results showed that there are different about isolated microbial density between samples collected from diseased and healthy pepper. The bacterial population is higher in rhizosphere region of healthy pepper than in those of diseased plants. In contrast, fungal density is lower in rhizosphere region of healthy plants than in those of diseased ones. From isolation plates, we selected and purified 391 strains including 236 bacteria, 149 actinomycetes and 6 fungi for screening antifungal activity. Out of isolated microorganisms, 44 strains (36 bacteria, 6 actinomycetes, and 2 fungi) showed antagonistic activity against at least one of two pathogens (F. oxysporum and R. solani), of which 15 isolates showed activity against both fungi. Identification of isolates with highest activity using the 16S rRNA gene sequences showed bacterial strains belonged to different species Enterobacter ludwigii, Pseudomonas fulva, Bacillus subtilis, whereas 2 actinomycetes belonged to the genus Streptomyces: Streptomyces sp. and Streptomyces diastatochromogenes. Identification of the isolated fungus based on morphological characteristics and the 18S rRNA gene sequence revealed that this strain belonged to species Penicillium oxalicum. Our study revealed the potential of the indigenous microorganisms in preventing and controlling plant-pathogenic fungi.

scholarly journals Isolation and Screening of Pectinolytic Bacterial Strains using Rotten Apples from Lahore, Pakistan

2019 ◽  
Vol 01 (03) ◽  
pp. 23-36
Author(s):  
Amna Yaqoob ◽  
Fatima Amanat ◽  
Asif Ali ◽  
Muhammad Sajjad
Keyword(s):  
Large Scale ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Scale Production ◽  
Bacterial Strains ◽  
Large Scale Production ◽  
Pectinolytic Activity ◽  
Juice Extraction ◽  
Rrna Gene Sequencing ◽  
Pectinase Production

Pectinases are pectin degrading enzymes predominantly used as biocatalysts in various industries such as wine extraction, fruit juice extraction, and making of paper pulp. Large scale production of pectinases using biological systems (bacteria, fungi, plants) is a common method used in the industry. In the current study, different bacterial isolates obtained from rotten apples were used for pectinase production and their pectinolytic activity was investigated. Five bacterial strains were isolated on the growth medium containing 0.3% KH2PO4, 0.6% Na2HPO4, 0.2% NH4Cl, 0.5% NaCl, 1% Pectin, 1.5% Agar, 1mM CaCl2, and 10mM MgSO4. The isolates of five samples A, B, C, D and E were then biochemically characterized as Serratia marcescens, Klebseilla pneumoniea, Pseudomonas aeruginosa and Escherichia coli, respectively. They were also identified at the molecular level through 16S rRNA gene sequencing.

scholarly journals Rhodanobacter sp. Strain BPC1 in a Benzo[a]pyrene-Mineralizing Bacterial Consortium

2002 ◽  
Vol 68 (12) ◽  
pp. 5826-5833 ◽  
Author(s):  
Robert A. Kanaly ◽  
Shigeaki Harayama ◽  
Kazuya Watanabe
Keyword(s):  
Bacterial Consortium ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Competitive Pcr ◽  
Pcr Assay ◽  
Biochemical Tests ◽  
Supernatant Liquid ◽  
Gene Sequence Analysis ◽  
High Boiling Point ◽  
Fuel Distillate

ABSTRACT A bacterial consortium which rapidly mineralizes benzo[a]pyrene when it is grown on a high-boiling-point diesel fuel distillate (HBD) was recovered from soil and maintained for approximately 3 years. Previous studies have shown that mobilization of benzo[a]pyrene into the supernatant liquid precedes mineralization of this compound (R. Kanaly, R. Bartha, K. Watanabe, and S. Harayama, Appl. Environ. Microbiol. 66:4205-4211, 2000). In the present study, we found that sterilized supernatant liquid filtrate (SSLF) obtained from the growing consortium stimulated mineralization of benzo[a]pyrene when it was readministered to a consortium inoculum without HBD. Following this observation, eight bacterial strains were isolated from the consortium, and SSLF of each of them was assayed for the ability to stimulate benzo[a]pyrene mineralization by the original consortium. The SSLF obtained from one strain, designated BPC1, most vigorously stimulated benzo[a]pyrene mineralization by the original consortium; its effect was more than twofold greater than the effect of the SSLF obtained from the original consortium. A 16S rRNA gene sequence analysis and biochemical tests identified strain BPC1 as a member of the genus Rhodanobacter, whose type strain, Rhodanobacter lindaniclasticus RP5557, which was isolated for its ability to grow on the pesticide lindane, is not extant. Strain BPC1 could not grow on lindane, benzo[a]pyrene, simple hydrocarbons, and HBD in pure culture. In contrast, a competitive PCR assay indicated that strain BPC1 grew in the consortium fed only HBD and benzo[a]pyrene. This growth of BPC1 was concomitant with growth of the total bacterial consortium and preceded the initiation of benzo[a]pyrene mineralization. These results suggest that strain BPC1 has a specialized niche in the benzo[a]pyrene-mineralizing consortium; namely, it grows on metabolites produced by fellow members and contributes to benzo[a]pyrene mineralization by increasing the bioavailability of this compound.

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