1. Application of Kocuria flavus (Kocuria flavus) in treating heavy metal polluted wastewater.

2. Use according to claim 1, wherein the heavy metal contaminated wastewater is copper contaminated wastewater.

3. The application of claim 2, wherein the concentration of copper ions in the copper polluted wastewater is 100-1000 mg/L.

4. The use according to claim 3, wherein the copper ion concentration in the copper-contaminated wastewater is 100mg/L, or 250mg/L, or 500mg/L, or 750mg/L, or 1000 mg/L.

5. Use according to any one of claims 1 to 4, comprising: adding fermentation liquor of yellow curia flavus into the copper polluted wastewater to be treated;

wherein the culture medium of the fermentation liquor is NB culture medium or NBU culture medium; the NBU culture medium contains 2% urea and 25mM CaCl₂NB medium of (1).

6. The use according to claim 5, wherein the culture medium of the fermentation broth is NBU medium.

7. The use according to claim 5, wherein the formulation of NB medium is as follows: 10g/L of peptone, 3g/L of beef extract powder, 5g/L of sodium chloride and 8.0 of pH.

Background

Waste water containing a large amount of copper ions is often generated in the processes of chemical industry, printing and dyeing, electroplating, nonferrous smelting, mining of nonferrous metals, rinsing waste water of electronic materials, dye production and the like. The main treatment methods of the copper-containing wastewater include a chemical precipitation method, an ion exchange method, an electrolysis method and the like. However, these methods use energy and chemicals at high cost, and thus it is necessary to find a low-cost and environmentally friendly treatment method.

Microbial remediation is receiving increasing attention as an effective biotechnology for remediating contaminated environments. Microbial Induced Calcification (MICP) offers another option to solve this problem. Urea-decomposing bacteria in the environment are capable of decomposing urea and secreting one or more metabolites that react with ions and compounds in the environment and produce mineral particle deposits.

In view of this, the invention is particularly proposed.

Disclosure of Invention

In order to promote the biological treatment research of the heavy metal polluted wastewater (especially the copper polluted wastewater), the invention provides the application of the Kocuria flavus (Kocuria flavus) in the treatment of the heavy metal polluted wastewater.

Specifically, the invention provides the following technical scheme:

the invention provides an application of yellow curia flavus (Kocuria flavus) in treating heavy metal polluted wastewater.

Preferably, the heavy metal polluted wastewater is copper polluted wastewater.

In the present invention, the Kocuria flavus (Kocuria flavus) is particularly suitable for treating copper-contaminated wastewater.

Preferably, the concentration of copper ions in the copper polluted wastewater is 100-1000 mg/L.

Further, the concentration of copper ions in the copper polluted wastewater is 100mg/L, 250mg/L, 500mg/L, 750mg/L or 1000 mg/L.

Preferably, the application comprises: adding fermentation liquor of yellow curia flavus into the copper polluted wastewater to be treated;

wherein the culture medium of the fermentation liquor is NB cultureMedium or NBU medium; the NBU culture medium contains 2% urea and 25mM CaCl₂NB medium of (1).

Further, the culture medium of the fermentation broth is NBU culture medium.

Preferably, the formula of the NB medium is as follows: 10g/L of peptone, 3g/L of beef extract powder, 5g/L of sodium chloride and 8.0 of pH.

The invention has the beneficial effects that:

the invention discovers that the yellow-flowered skullcap (Kocuria flavus) has obvious effect in treating the copper-polluted wastewater, and the yellow-flowered skullcap (Kocuria flavus) can effectively remove more than 90% of copper ions in the copper-polluted wastewater; the strain is very environment-friendly, has strong adaptability, low propagation cost and great application potential.

Drawings

FIG. 1 is a graph showing the copper removal rate and urease activity of Kocuria flavus (Kocuria flavus) as a function of time;

FIG. 2 is a graph showing the growth of Xanthomonas campestris (Kocuria flavus) and the Cu removal rate as a function of Cu concentration.

Detailed Description

The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

The examples do not show the specific techniques or conditions, according to the technical or conditions described in the literature in the field, or according to the product specifications. The reagents or instruments used are conventional products available from regular distributors, not indicated by the manufacturer.

The formulation of NB medium used in the following examples is as follows: 10g/L of peptone, 3g/L of beef extract powder, 5g/L of sodium chloride and 8.0 of pH.

The formulation of the urea agar medium used in the following examples is as follows: 1.0g/L of gastrone, 1.0g/L of D-glucose, 5.0g/L of sodium chloride, 1.2g/L of disodium hydrogen phosphate, 0.8g/L of dipotassium hydrogen phosphate, 0.012g/L of red and 15.0g/L of agar; the preparation method comprises the following steps:

1) weighing 24g of urea agar base, and resuspending with 950ml of deionized water;

2) heating and boiling until the mixture is completely dissolved;

3) sterilizing at 115 deg.C for 20 min;

4) cooling to 50 deg.C, adding 50ml sterile 40% urea solution;

5) mixing, packaging 10ml into sterile test tube, and preparing agar slant.

NBU medium used in the following examples was 2% urea (filter sterilized) and 25mM CaCl₂NB medium of (1).

Example 1 isolation and screening of Xanthomonas campestris (Kocuria flavus)

1) Collecting a copper-polluted soil sample by using a screw cap disinfection bottle;

2) 1g of a copper-contaminated soil sample was inoculated into 50ml of a solution containing 100mg/L copper (CuSO)₄·5H₂O) in nutrient broth (NB medium) for 48 hours at 30 ℃ under shaking conditions (130 rpm);

3) bacteria were counted using serial dilution full plate counting method using nutrient agar with different copper concentrations (25, 50 and 100 mg/L);

4) the petri dish was incubated overnight at 30 ℃; subsequently, the colonies were transferred onto urea agar medium (urease selection medium) to check urease production (since urease is a key indicator of calcite production);

5) yellow kukoku fungus (Kocuria flavus) was finally selected in view of higher urease-producing ability and growth ability in a copper-containing medium; the strain and the extracts of the fermentation supernatant and the thallus thereof have obvious effect on treating the copper-polluted wastewater.

Example 2 identification of Xanthomonas campestris (Kocuria flavus)

1) The strain obtained by screening in the example 1 is cultured overnight, and the genome DNA is extracted by an alkaline lysis method;

2) amplifying the 16S rRNA gene in the genome DNA by PCR;

3) the 16S rRNA amplicon was gel eluted and ligated into pTZ57R/T vector (enzyme company, USA) according to the manufacturer' S instructions;

4) sequencing by using an automatic sequencer of an applied biological system; kuelia flava (Kocuria flavus) is gram-positive and belongs to the phylum Actinomyceta and Micrococcus;

5) phylogenetic analysis of 16S rDNA revealed that the gene of Kocuria flaviviruses (Kocuria flaviviruses) had 100% similarity to the commercial Kocuria flaviviruses (Kocuria flaviviruses).

Example 3 use of Coprinus flavus (Kocuria flavus) for treating copper-contaminated wastewater

1) To a 100ml flask, 50ml of NB medium containing 100mg/L of Cu ions and 50ml of NBU medium containing 100mg/L of Cu ions were added, respectively;

2) inoculating yellow curia flaviviridae (Kocuria flaviviridae) to the two culture mediums in step 1), as shown in fig. 1, wherein 95% of copper ions (100mg/L) are effectively removed in NBU culture medium within 120 hours; in NB medium, 68% of copper ions were effectively removed.

In this example, the selected Kocuria flaviviruses (Kocuria flavus) can be isolated according to the method of example 1, or commercially available Kocuria flaviviruses (Kocuria flavus) can be selected; that is, the isolated yellow Kurilla (Kocuria flavus) and the commercially available yellow Kurilla (Kocuria flavus) in example 1 can achieve the technical effects of the present invention.

Example 4 application of Kukukola (Kocuria flavus) to treatment of copper-contaminated wastewater

1) The effect on the growth of Kocuria flavus and the copper removal effect were examined using copper ion solutions of different concentrations (250mg/L, 500mg/L, 750mg/L and 1000 mg/L);

the method specifically comprises the following steps: 50ml of NBU medium containing 250mg/L of Cu ions, 50ml of NBU medium containing 500mg/L of Cu ions, 50ml of NBU medium containing 750mg/L of Cu ions, and 50ml of NBU medium containing 1000mg/L of Cu ions were added to 100ml of flasks, and then Cocuria flavus (Kocuria flavus) was inoculated to each medium;

2) as shown in fig. 2, the yellow curia (Kocuria flavus) effectively removed a higher amount of Cu at a high concentration of Cu; in the NBU culture medium containing 250mg/L, the removal rate of copper is 92 percent; in the NBU culture medium containing 500mg/L, the removal rate of copper is 95 percent; in NBU culture medium containing 750mg/L, the removal rate of copper is 96%; the removal rate of copper in NBU medium containing 1000mg/L was 97%.

In this example, the selected Kocuria flaviviruses (Kocuria flavus) can be isolated according to the method of example 1, or commercially available Kocuria flaviviruses (Kocuria flavus) can be selected; that is, the isolated yellow Kurilla (Kocuria flavus) and the commercially available yellow Kurilla (Kocuria flavus) in example 1 can achieve the technical effects of the present invention.

Although the invention has been described in detail hereinabove with respect to a general description and specific embodiments thereof, it will be apparent to those skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.