Damage to DNA of effective microorganisms by heavy metals:Impact on wastewater treatment

The research is to test the damage to DNA of effective microorganisms(EMs)by heavy metal ions As3+,Cd2+,Cr3+,Cu2+,Hg2+, Pb2+,and Zn2+,as well as the effects of EM bacteria on wastewater treatment capability when their DNA is damaged.The approach applied in this study is to test with COMET assay the damage of EM DNA in wastewater with different concentrations of heavy metal ions As3+,Cd2+,Cr3+,Cu2+,Hg2+,Pb2+,Zn2+,as well as the effects of EM treated with As3+,Cd2+,Cr3+,Cu2+,Hg2+,Pb2+,and Zn2+ on COD degradin...

Responses of Soil Fauna Structure and Leaf Litter Decomposition to Effective Microorganism Treatments in Da Hinggan Mountains,China

Microorganisms are nutritious resources for various soil fauna.Although soil fauna grazing affects microorganism composition and decomposition rate,the responses of soil fauna and leaf litter decomposition to added microorganism is little understood.In this study,in the coniferous and broad-leaved mixed forest of Tahe County in the northern Da Hinggan Mountains,China,three sampling sites(each has an area of 10 m2) were selected.The first two sites were sprinkled with 250 times(EM1) and 1000 times(EM2) diluted effective microorganism(EM) preparations evenly,and the third site was sprinkled with the same volume of water as a control site.The responses of soil fauna structure and leaf litter decomposition to EM treatment were conducted during three years.The results revealed that EM treatment resulted in significant increase of soil organic matter.The number of soil fauna in the EM1 and EM2 sites increased by 12.88% and 2.23% compared to the control site,and among them springtails and mites showed the highest increase.However,the groups of soil fauna in the EM1 and EM2 sites decreased by 6 and 9,respectively.And the changes in the diversity and evenness index were relatively complicated.EM treatment slowed the decomposition of broad-leaved litter,but accelerated the decomposition of coniferous litter.However,the decomposition rate of broad-leaved litter was still higher than that of coniferous litter.The results of this study suggested that the added microorganisms could help individual growth of soil fauna,and this method led to a change in the process of leaf litter decomposition.This paper did not analyze the activity of soil microorganisms,thus it is difficult to clearly explain the complex relationships among litter type,soil fauna and soil microorganisms.Further research on this subject is needed.

Studies on Solubility and Stability of Oligochitosan in Effective Microorganisms

[Objective] This study aimed to explore the synergistic effect of oligochi- tosan and EM bacteria and provide a theoretical basis for its application in animal health, aquaculture, sewage treatment and other fields. [Method] Different concentrations of oligochitosan were added into EM bacteria liquid and the stability was preliminarily studied. [Result] Addition of oligochitosan with appropriate proportion had played a supporting role in the stable storage of EM bacteria liquid and had shown certain inhibition effect on flatulence of EM bacteria liquid. Addition of oligochitosan had no significant effect on the quality and re-fermentation of EM bacteria. [Conclusion] The study indicated that oligochitosan could be utilized in conjunction with EM bacteria liquid, having a promising practical potential application.

Effect of Inoculation with Effective Microorganisms and Leachate Recycle on Degradation of Municipal Refuse

Biodegradation of waste in landfill is a slow process requiring decades for completion. Accelerated degradation of municipal refuse in modulated landfill environments may alleviate or eliminate pollution to the land, water and air. In this work, nineteen effective microorganisms (EMs) were isolated from old landfill refuse by enrichment culturing techniques and used for the inoculum of municipal refuse. The preliminary experiments demonstrate that a combination of EMs inoculation in landfill with leachate recycle resulted in increased rates of decomposition and faster process stability. The concentrations of COD, VFA and SO4^2- in digester with EMs inoculation and leachate recycle decreased more rapidly than others. Gas production from digester with EMs inoculation and leachate recycle commenced around 32 days, which is a week shorter than with leachate recycle only. And peak cumulative gas production was obtained much earlier in digester with EMs inoculation and leachate recycle (150 days) compared to 180 days with leachate recycle only. Moreover, in the first two months, the rate of settlement in digester with EMs inoculation and leachate recycle was more rapid than others.

Effects of Synergy between Earthworms and Effective Microorganisms on Vermicomposting of Pig Manure

[ Objective] To explore the effects of synergy between earthworms （ Eisenia foetida） and effective microorganisms （EM） on vermicom. posting of pig manure and to provide a new idea for rational and effective utilization and treatment of animal manure. [Method] Four treatments were used to compost pig manure, namely, EM-inoculated manure, earthworms-inoculated manure, EM and earthworms-inoculated manure and control （CK） manure. The experiment lasted for 60 d. On Day 0, 15, 30, 45 and 60, the pig manure was collected, and the content of total organic carbon （TOC）, total Kjeldahl nitrogen （TKN）, ammonium nitrogen, nitrate nitrogen and water soluble carbon （WSC） was determined, respectively. [Resuit] Compared with the control, the EM and earthworms-inoculated manure had a decrease of 42.8% in the TOC content, an increase of 13.6% in the TKN content, a decrease of 49.5% in the carbon nitrogen ratio, the conversion rate of ammonium nitrogen of 98.1%, a 96 times increase in nitrate nitrogen, the ratio of nitrate nitrogen to ammonium nitrogen of 61, and a decrease of 58.9% in the WSC content. [ Conclusion] The synergy between earthworms and EM can accelerate maturation of pig manure and improve mineralization and stability of products.

In Vitro Antibacterial Effect of Effective Microorganisms( EM) on Aeromonas hydrophila

In order to understand in vitro antibacterial effect of antibiotics and EM on Aeromonas hydrophila,14 isolates of A. hydrophila were isolated from diseased fish and aquaculture in the study. PCR amplification results of aerolysin gene( Aero gene) of isolates indicated that 7 out of 14 isolates were pathogenic A.hydrophila. In vitro antibacterial test indicated that 14 isolates were resistance to penicillin G,ampicillin,cephradine,cefazolin,tetracycline,terimethoprim,lincomycin and cephalexin,but showed high sensitivity to cefotaxime and furazolidone. In vitro antibacterial effect of EM on 14 isolates of A. hydrophila was positively correlated with concentration,and EM with the concentration greater than 60% had antibacterial effect on 14 isolates.

Influence of Microorganisms Effective against Basal Rot and on Agronomic Parameters of Onion [Allium cepa L. (Amaryllidaceae)]

Onions are a horticultural crop of great economic, dietary and medicinal importance, and are highly prized by the Ivorian population. However, production remains low, due to a number of constraints, including parasitic attacks. The most frequent is fusariosis caused by Fusarium sp., a pathogen that causes enormous damage to onion crops. Faced with these attacks, chemical control appears to be ineffective, with consequences for human health and the environment. This is why the search for effective alternative methods that respect the environment and human health is so necessary. It is in this context that this study was carried out, with the general aim of controlling fusarium wilt in onion crops, with a view to improving onion production in Ivory Coast through the use of effective microorganisms. The experimental set-up used for this purpose was a fisher block with complete randomization, comprising three replicates. A fungal spore concentration of 106 spore/mL of Fusarium sp., three doses (1%;2.5% and 5% v/v) of EM and one dose of a chemical fungicide (30 mL/16L) were tested on young onion plants. Each block consisted of nine sub-plots with nine treatments. Health parameters (incidence and severity) and agronomic parameters (growth and yield) were assessed. Microbiological analysis of the EM revealed the presence of nine morphotypes of Trichoderma sp., Aspergillus clavatus, Aspergillus flavus, Aspergillus sp., Penicillium sp., Rhizopus sp., lactic acid bacteria of the Bacillus family and the yeast Saccharomyces cerevisiae. Field experimentation showed that the 5% EM microbial solution reduced the incidence and severity of fusariosis compared with the chemical fungicide, and proved to be the best. This dose reduced yield losses by 7.14%, while improving onion growth and yield by over 5%. The results demonstrated the ability of the EM solution to effectively control the causal agent of basal rot in onion crops.

Bioremediation of nitrogen-and phosphorus-polluted aquaculture sediment by utilizing combined immobilized effective microorganisms and sediment aeration technology

The endogenous release of nitrogen and phosphorus from aquaculture sediment can continuously pollute the water quality in aquaculture ponds.In this study,an integrated bioremediation approach that combined effective microorganisms(EM)with aeration techniques was designed to restore contaminated aquaculture sediment.Initially,a set of laboratory-scale experiments was designed to evaluate the feasibility of the technology for the bioremediation of nitrogen and phosphorus.The removal and transformation efficiency indexes of both the overlying water and sediment were measured.From the obtained results,the combination of sediment aeration and immobilized EM significantly improved the nitrogen and phosphorus removal rate from the overlying water and sediment when compared to other methods.Subsequently,a series of field-scale experiments was further implemented to assess the integrated technique in practical applications.In field experiments,the variation in the comprehensive trophic level index(TLI)and sediment biodegradation activities(G value)was used to assess the effect of sediment bioremediation.In pond II which promotes sediment biodegradation,the values of TLI varied from 70.13 to 54.16,and the classification level changed from Hypereutrophic to a Light eutrophic.In addition,the G value increased from 0.98 kg/(kg·h)to 2.12 kg/(kg·h).The organic matter(OM)and sediment thickness(ST)decreased by 17.4 g/kg and 2.3 cm,respectively.The obtained results indicated that the combination of EM and sediment aeration might be feasible and effective for the remediation of nitrogen-and phosphorus-polluted aquaculture sediment.

Heavy metals and community structure of microorganism changes during livestock manure composting with inoculation of effective microorganisms

Effective microorganisms(EM)is usually used in composting to improve the composting process.However,the effect of EM on heavy metals evolution was still unclear.This study was performed to illustrate the microbial community changes that occur during composting with the addition of EM and to determine the evolution of heavy metal speciation during this process.The requirement of harmlessness for pig manure was met after the addition of EM at a dosage of 0.5%,with a germination index of 96.42%.The bacterial and fungal diversity were both found to decrease during the composting process.Additionally,the bioavailability of Cu and Pb decreased significantly during composting.Significant correlations were observed between the microbial composition and the percentage of different heavy metals fractions;however,the mechanism responsible for this correlation requires further investigation.This study has the potential to contribute to control of heavy metal contamination during the process of recycling pig manure through the controlled addition of EM.

Composting MSW and sewage sludge with effective complex microorganisms

The effects of complex microorganisms in composting process of the municipal solid waste (MSW) and sludge were examined through inspecting biomass, temperature, oxygen consumption, organic mater, and C/N (the ratio of carbon and nitrogen). The experimental results shows: complex microorganisms are effective to compose organic matter and speedup composting change into humus.

Corn Leaf Water Retention as Affected by OrganicFertilizations and Effective Microbes Applications

Effects of organic fertilizers and effective microbes on leaf water retention of sweet corn (Zea mays L. cv.Honey-Bantam) were studied. Sweet corns were grown with organic or chemical fertilizers with or without effective microbes (EM). A water retention curve was obtained by drying the excised leaves under a light of 500 μmol (m2·s)-1. The curve shows two distinct phases. The initial steep slope indicates the water loss speed by stomatal transpiration (Est) and the gentle slope of the second phase indicates water loss speed by cuticular transpiration (Ecu). Both Est and Ecu were lower for leaves of plants grown with organic materials than for those with chemical fertilizers. Addition of EM to both organic and chemical fertilizers decreased Est but showed no effect on Ecu. The water retention ability of the excised leaves was proportional to photosynthetic maintenance ability under soil water deficit conditions as well as the solute concentration in leaves. The results suggested that organic fertilization and EM application increased water stress resistance both under in situ conditions and in excised leaves of sweet corn plants.

Preliminary Studies on Chlorimuron Degradation in Soil by Effective Microogranisms

A wheat （Triticum aestivurn L.） bioassay method was used for preliminary determination of chlorimuron degradation in soil by EM （effective microorganisms）. Under the conditions of this study, chlorimuron half-life was greater than 30-50 days in soil containing different initial concentrations of chlorimuron. After adding EM, chlorimuron degradation half-life ranged from 10-15 days, which was about 15-30 days shorter than without EM. Chlorimuron degradation was not significantly affected by EM populations applied at 50-200 mL·kg^-1. Both monopotassium phosphate and urea enhanced the ability of EM to degrade chlorimuron, but brown sugar had no significant effect.