Use Of Microbial Technology Research Articles

The characteristics of H6 against Microcystis aeruginosa.

Algal bloom caused by Microcystis aeruginosa has always been the focus of attention; microbial algal control has the advantages of significant effect, low investment cost, and environmental friendliness; the use of microbial technology to inhibit the bloom has a broad prospect for development. In this study, a strain of Enterobacterium algicidal bacteria screened from a river was used to study the algicidal characteristics against Microcystis aeruginosa using SEM, 3-D EEM and zeta potential. The results showed that the optimal dosage (v/v) of the strain was 5% and the removal rate of algal cells was 70% after 7 days. When the algal density was OD680nm = 0.3, the removal rate of algal cells reached 83% after 7 days. In the pH range of 5 ~ 11, the removal rate of algal cells was 70 ~ 80% after 7 days. Algicidal bacteria H6 is mainly indirect algae lysis and is supplemented by direct algae lysis. Algicidal bacteria H6 removes algicidal substances by secreting high temperature resistant algicidal substances and algicidal products are humic acids. Algicidal bacterium H6 was a strain of Enterobacterium with good algicidal effect in a wide pH range, which enriched the bacterial resources in the control of cyanobacteria bloom in water. The high temperature resistance of the algae-soluble substance secreted by the algae-soluble substance provided convenience for the subsequent preparation and application of bacterial powder.

Approaches in Bioremediation of Dioxins and Dioxin-Like Compounds – A Review on Current and Future Prospects

Waste generation is becoming increasingly prominent in the environmental arena due to the increase in population and living standards of life. Dioxin and Dioxin-related compounds are a set of hazardous chemicals that are ubiquitously distributed. Polychlorinated dioxins are introduced into our surroundings by both spontaneous and induced activities like combustion, incineration of waste, recycling of e-waste, and paper and pesticide manufacturing. They are chloroaromatic compounds that are found to be lethal and possess carcinogenic properties and are one of the primary examples of persistent environmental pollutants (POP). Removal of these compounds from the environment is very challenging due to their recalcitrant nature. An alternative technique is the use of microbial technology which includes the use of bacteria and fungi to detoxify the dioxins that are considered to be a more effective, economical, and environmentally sustainable alternative. Different microbial interactions were studied for their degradation potential. Polychlorinated dibenzo-p-dioxin and furans (PCDD/F) are found to be degraded by bacteria by adopting either aerobic or anaerobic pathways and the details regarding the diversity, distribution, bioremediation potential, metabolic pathway have been analyzed. This review provides an overview of the source of contamination, its potential toxicity assessment, and various bioremediation techniques that are employed are discussed in detail. It also highlights the nanoremediation technique - a promising tool in which nanoparticles are used in the treatment of toxic organic pollutants.

Responding to Future Earth's Biodiversity Goals: Implementing Ecological Services, Agricultural Diversity and Bioresource Sustainability of the Shallow Mountain Slope Ecosystem in Dongshan District

Climate change and the resultant extreme weather events have disrupted agricultural ecosystems. In South Taiwan, serious droughts and unpredictable, heavy rainfall have caused slope sliding at lowland areas and led to significant agricultural and economic loss. A team of researchers led by Professor Tzen-Yuh Chiang, that includes Dr Tsai-Wen Hsu and Professor Yu-Chung Chiang, and is based at the University Social Responsibility, National Cheng Kung University, Taiwan, wants to drive change in farming practices in the Dong Shan district, Taiwan. In work supported by the Ministry of Science and Technology in Taiwan, the team is introducing a combination of natural and microbial farming practices. As such, the researchers have isolated and reformulated microbial fertilisers in the lab and applied them to enforce the health of crop roots. They have found that many insects and birds are now back on the farm, acting as biological control, which removes the need for pesticides. The overall goal of the project is to rebuild the vegetation and natural ecosystem along the slopes of lowlands. Key to this is stopping slope exploration, along with using microbial farming practices to enforce and ensure the health of crops. The project's success also relies on the use of microbial technology to culture microbes with sterile medium, which can then be used as fertilisers. This important work will help to integrate knowledge and policy about the agricultural environment and the agricultural economy.

The Use of Microbial Technology to Soil Stabilization

Microbially exacerbate existing precipitation (MICP) is an emerging technique with great potential for enhancing soil quality. The study's overarching objective is to quantify MICP's contribution to black cotton soil's improved shear strength and reduced hydraulic conductivity. The findings of a laboratory study on the influence of microorganisms on the engineering properties of soil treated with MICP. The bacteria utilized in this study was called Bacillus megaterium. A mold was made with the same interior size as the vortex shear instrument, and soil samples were then tested using this setup. The presence of microbes in black cotton soil greatly improves its shear strength and decreases its hydraulic conductivity, as shown by vane shear and penetration tests.

Experimental investigation of the use of methanotrophs for the degradation of low-concentration methane

Methanotrophs (methane-oxidizing bacteria) can degrade methane into carbon dioxide and water. In this paper, several types of methanotrophs have been successfully cultivated and sorted out based on microbial technology, and the processes and approaches used are described in detail. By using several types of active methanotrophs, a few groups of experimental investigations have been carried out to determine their degradation effects on methane gas; these studies used different low methane concentrations that were less than 1.5%. The experimental results showed that the methanotrophs studied can still show the characteristics of normal activity under the conditions of a series of low methane concentrations that ranged from 0.25 to 1.5%. In the degradation process, with the increased methane concentrations in the mixed gas, more methane could ultimately be degraded to carbon dioxide. The decrease in methane and increase in carbon dioxide presented approximately linear relationships, and the numerical relationships between carbon dioxide and methane and the microbial degradation times could be described by exponential functions with high correlations. The conclusions in this paper attempt to forge a new path for the prevention of exceeding limited methane concentrations during coal mining by the use of microbial technology.

Rock-Solubilizing Microbial Inoculums Have Enormous Potential as Ecological Remediation Agents to Promote Plant Growth

Anthropogenic overexploitation poses significant threats to the ecosystems that surround mining sites, which also have tremendous negative impacts on human health and society safety. The technological capacity of the ecological restoration of mine sites is imminent, however, it remains a challenge to sustain the green restorative effects of ecological reconstruction. As a promising and environmentally friendly method, the use of microbial technologies to improve existing ecological restoration strategies have shown to be effective. Nonetheless, research into the mechanisms and influences of rock-solubilizing microbial inoculums on plant growth is negligible and the lack of this knowledge inhibits the broader application of this technology. We compared the effects of rock-solubilizing microbial inoculums on two plant species. The results revealed that rock-solubilizing microbial inoculums significantly increased the number of nodules and the total nodule volume of Robinia pseudoacacia L. but not of Lespedeza bicolor Turcz. The reason of the opposite reactions is possibly because the growth of R. pseudoacacia was significantly correlated with nodule formation, whereas L. bicolor’s growth index was more closely related to soil characteristics and if soil nitrogen content was sufficient to support its growth. Further, we found that soil sucrase activity contributed the most to the height of R. pseudoacacia, and the total volume of root nodules contributed most to its ground diameter and leaf area. Differently, we found a high contribution of total soil carbon to seedling height and ground diameter of L. bicolor, and the soil phosphatase activity contributed the most to the L. bicolor’ s leaf area. Our work suggests that the addition of rock-solubilizing microbial inoculums can enhance the supply capacity of soil nutrients and the ability of plants to take up nutrients for the promotion of plant growth. Altogether, our study provides technical support for the practical application of rock-solubilizing microbes on bare rock in the future.

Microbes as remediating agents in detoxification of dyes

Dyes are colored substances being used to color various types of fabrics and materials from ancient time. During their use in the coloring of various types of materials as well as during their synthesis; they come out in the environment as such or in the form of toxic by-products and by mixing in aqueous system generate various types of problems to organisms living in that aqueous environment as well as human beings using that polluted water in any way. Several techniques are being used in the present time to solve such environmental problems. In this direction, many researches are also running on the green use of microbial technology in bioremediation of toxic, carcinogenic and extremely harmful unused dye’s products as well as its by-products by elimination or degradation or de-colorization. This mini-review discusses about the some recent researches done in this field in order to solve this problem and future aspect of the use of this green technology

Overview of microbial technology in the utilization of rare earth resources

As an important resource for the development of modern industry, rare earth elements are widely used in nuclear technology, batteries, permanent magnet, electronic products, catalysis, and superconducting technology, and they have been mined at a considerable large scale. China’s rare earth resources are abundant, and their reserves account for approximately 36.7% of the world’s total reserves. Over the recent years, global rare earth resources are generally faced with over-exploitation, low utilization rates, and serious environmental pollution problems. Therefore, there is an urgent need for the development of recovery systems that are inexpensive and cause less pollution. Rare earth elements can be widely involved in the metabolism of compounds in various micro-organisms and may have mining capabilities. The use of microbial technology to mine and recover rare earth resources has provided a novel green and efficient method for the utilization of rare earth resources, and research in related fields has continued intensify. This paper primarily introduced the important role and utilization status of rare earth resources, summarized the distribution and characteristics of rare earth minerals in China, and identified the problems associated with rare earth mining and the advantages of microbial mining. Furthermore, it reviewed the development process of rare earth mining using micro-organisms, summarized its research progress, and introduced the research mechanism of microbial mining, primarily including related research on the mechanism of microbial leaching, adsorption and accumulation of rare earth elements, separation methods, species distribution, and mechanism action of rare earth ore mining microorganisms. Considering minerals of the Bayan Obo deposit in China and the Mount Weld deposit in Australia as examples, the extraction of rare earth elements from ore by microbes selected from the surrounding environment has been explained. Moreover, the recovery of rare earth elements in low-grade ore and waste by micro-organisms has been briefly described. Based on the current status of microbial mining of rare earth ore, future challenges and prospects of microbial utilization of rare earth elements have been proposed.

Improved Maize Growth in Condition Controlled by PGPR Inoculation on Ferruginous Soil in Central Benin

The use of microbial technologies in agriculture is rapidly expanding with the discovery of new bacterial strains effective in improving plant growth. In this study, we tested and highlighted the efficacy of PGPR (Plant Growth Promoting Rhizobacteria) alone or in a consortium on maize growth. For this purpose, a greenhouse experiment was carried out in pots containing sterilized ferruginous soil for 30 days. The corn seeds of the EVDT 97 SRT C1 variety were inoculated with bacterial suspensions of concentration 108 UFC/ml. The experimental device was a random block of 16 three-repeat treatments. The incidence of PGPR inoculated strains is assessed on the biomass growth and yield parameters of maize. At the end of the trial, the results showed that inoculation stimulated plant growth and development and resulted in a significant increase in the height, diameter at the collar, leaf surface and dry weight of aerial biomass of 20.15%, 21%, 32.77% and 37.73% respectively compared to controls, especially in corn plants inoculated with B. thurengiensis + B. panthéthonicus + S. marcescens and Pseudomonas cichorii + Pseudomonas putida + Pseudomonas syringae. These results show the potential of using these rhizobacteria as biological inoculants to improve maize productivity in Benin.

Improved Maize Growth in Condition Controlled by PGPR Inoculation on Ferruginous Soil in Central Benin

The use of microbial technologies in agriculture is rapidly expanding with the discovery of new bacterial strains effective in improving plant growth. In this study, we tested and highlighted the efficacy of PGPR (Plant Growth Promoting Rhizobacteria) alone or in a consortium on maize growth. For this purpose, a greenhouse experiment was carried out in pots containing sterilized ferruginous soil for 30 days. The corn seeds of the EVDT 97 SRT C1 variety were inoculated with bacterial suspensions of concentration 108 UFC/ml. The experimental device was a random block of 16 three-repeat treatments. The incidence of PGPR inoculated strains is assessed on the biomass growth and yield parameters of maize. At the end of the trial, the results showed that inoculation stimulated plant growth and development and resulted in a significant increase in the height, diameter at the collar, leaf surface and dry weight of aerial biomass of 20.15%, 21%, 32.77% and 37.73% respectively compared to controls, especially in corn plants inoculated with B. thurengiensis + B. panthéthonicus + S. marcescens and Pseudomonas cichorii + Pseudomonas putida + Pseudomonas syringae. These results show the potential of using these rhizobacteria as biological inoculants to improve maize productivity in Benin.

Isolation and Molecular Characterization of a Model Antagonistic Pseudomonas aeruginosa Divulging In Vitro Plant Growth Promoting Characteristics.

The use of microbial technologies in agriculture is currently expanding quite rapidly with the identification of new bacterial strains, which are more effective in promoting plant growth. In the present study 18 strains of Pseudomonas were isolated from soil sample of Balochistan coastline. Among isolated Pseudomonas strains four designated as SP19, SP22, PS24, and SP25 exhibited biocontrol activities against phytopathogenic fungi, that is, Rhizopus microsporus, Fusarium oxysporum, Aspergillus niger, Alternaria alternata, and Penicillium digitatum; PS24 identified as Pseudomonas aeruginosa by 16srRNA gene bank accession number EU081518 was selected on the basis of its antifungal activity to explore its potential as plant growth promotion. PS24 showed multiple plant growth promoting attributes such as phosphate solubilization activity, indole acetic acid (IAA), siderophore, and HCN production. In order to determine the basis for antifungal properties, antibiotics were extracted from King B broth of PS24 and analyzed by TLC. Pyrrolnitrin antibiotic was detected in the culture of strain PS24. PS24 exhibited antifungal activities found to be positive for hydrogen cyanide synthase Hcn BC gene. Sequencing of gene of Hcn BC gene of strain PS24 revealed 99% homology with the Pseudomonas aeruginosa strain PA01. The sequence of PS24 had been submitted in gene bank accession number KR605499. Ps. aeruginosa PS24 with its multifunctional biocontrol possessions can be used to bioprotect the crop plants from phytopathogens.

Study on Gas Control in Coal Mine by Methanotrophic Bacteria M02

Gas control technologies traditionally base on the physical properties of gas. However, making use of microbial technology is another way to deal with coal seam gas. This paper conducted the laboratory test firstly, selected a bacteria M02 to degrade methane efficiently, and the strains were identified as Methylophilus sp.; the conservation of matter experiment verified its ability of methane degradation; then the industrial experiment was implemented in the coal mine underground showed that by the use of methanotrophic bacteria, and the gas concentration of return air, gas content, gas pressure and the index of K1-value had been decreased in different degree. Hence large-scale use of microbial technology on gas control is feasible.

Isolation and Characterization of Plant Growth Promoting Traits of a Rhizobacteria: Pantoea agglomerans lma2

The use of microbial technology in agriculture is expanding quickly with the identification of new bacterial strains which are more effective in promoting the growth of plants. The rhizobacteria that promote the growth of plants can have a positive effect on the productivity of crops especially when subjected to salt stress. A nitrogen-fixing bacterium was isolated from the wheat rhizosphere of an arid region. The strain was identified on the basis of tests API20E and 16S rRNA sequencing, as Pantoea agglomerans lma2. This strain degraded several carbon sources: sugars (fructose, ribose, dextrin, salicin...), lipids (lecithin, tributyrin and tween 80), proteins (gelatin, casein), grew on KCN and could grow from pH 4 to 8 and had an optimum at pH 7. The growth temperature showed a maximum at 30 degrees C and the bacteria could tolerate from 4 to 41 degrees C and the growth rate was higher when the NaCl concentration was between 100 and 300 mM. The performance of activities enhancing the growth of plants of P. agglomerans lma2 was significantly better in the presence of salt. Rates of Indole Acetic Acid (IAA), siderophores production and solubilization of phosphate increased between 100 and 400 mM NaCl compared to the control without salt. The maximum values were saved to 300 mM for the production of siderophores (18.32%) and solubilization of phosphate (1061.49 microg mL(-1)) and 100 mM for the production of IAA (161 microg mL(-1)). A significant correlation existed between these three activities. These results showed that P. agglomerans lma2 with its Plant Growth Promoting Rhizobacteria (PGPR) and halophilic properties could constitute a good fertilizer in arid and saline zone.

Isolation and Characterization of Rhizobacteria for their Many Activities Improving the Plant Growth

The use of microbial technology in agriculture extends currently relatively quickly with the identification of new more efficient bacterial strains in the growth of plants. The rhizobacteria that promote the growth of plants (PGPR, plant growth promoting rhizobacteria) can have a positive effect on the productivity of crops( Chaiharn et al., 2008) especially when subjected to salt stress ( Tripathi et al., 1998). Indeed, the salinity considerably affects the crop yield. Inoculating PGPR can mitigate the effects of this type of stress by direct or indirect mechanisms (Ahmad et al., 2008). To select effective strains and having multiple activities, a total of 22 bacterial strains are isolated from different soils. These strains are characterized by their ability to fix nitrogen (nitrogen-free medium culture). They are also tested in vitro for their activities of improvement of plant growth such as the production of the indole acetic acid (IAA) of hydrogen cyanide (HCN), of the siderophore, ammonia (NH3), of solubilization of phosphates and antifungal activity. More than 70% of the strains produce NH3, 54% solubilized more P2O5 10µg/ml and the same rate and has antifungal activity against ≥ to three fungal strains. However, 36% produce more 80µg/ml of IAA, 27% produce siderophores and only two strains produced of HCN. The production of IAA of eight (08) strains is evaluated in the presence of 100, 200 and 300 mM NaCl. The remaining active strains with high concentration of NaCl would be the most effective and can be considered as biofertilizers for improving plant growth in areas affected by salinity.