Screening method for petroleum degrading bacteria, method for preparing petroleum degrading bacteria inoculant from screened bacteria, and application of inoculant

Abstract

The invention relates to a screening method for petroleum degrading bacteria. An enrichment medium, a screening medium and a domestication medium, which are used in the method, are media employing petroleum as a unique carbon source, and specifically, petroleum polysorbate-80 solubilizing fluid is specifically added into the media. The method has the beneficial effects that a nonionic surfactant polysorbate-80 is used as a solubilizing agent, so that the dissolution effects of petroleum in water can be improved, and the problem of difficulty in the dissolution of petroleum in the media is solved; petroleum is actually the unique carbon source, and the petroleum polysorbate-80 solubilizing fluid is used as the carbon source of the media in processes of primary screening, domestication, purification and the like of the petroleum degrading bacteria; the screening of the petroleum degrading bacteria comprises the processes of primary screening, domestication, purification and the like, a strain is gradually domesticated to be adapted to growth and reproduction under the condition of employing petroleum as the unique carbon source in the domestication medium of which the petroleum concentration gradient gradually rises, and tolerance to petroleum and the degradation efficiency are improved.

Description

technical field [0001] The invention relates to the technical field of microbial remediation of petroleum-contaminated soil, in particular to a screening method for petroleum-degrading bacteria, a method for preparing a petroleum-degrading bacterial agent from the screened bacteria, and an application of the bacterial agent in oil-contaminated soil remediation. Background technique [0002] Petroleum is a complex mixture containing a variety of hydrocarbons (normal alkanes, branched alkanes, aromatic hydrocarbons, alicyclic hydrocarbons) and a small amount of other organic compounds (sulfides, nitrides, naphthenic acids, etc.), and is the most important chemical substance for human beings. One of energy. In the process of oil extraction and transportation, oil leakage is often accompanied, causing environmental pollution. Especially polycyclic aromatic hydrocarbons (Polycyclic Aromatic Hydrocarbon-bon, PAHs) have become a huge threat to human health due to their poor bioava...

AI Technical Summary

Problems solved by technology

Compared with liquid fermentation, solid-state fermentation has the following disadvantages: limited to microorganisms resistant to low water activity, less selection; slow fermentation rate and long cycle; complex natural raw material components, sometimes changing, affecting yield quality; difficult to detect and control process parameters; The operation consumes a lot of labor and is intensive

In this experiment, 1, 2, and 3 g of petroleum were added to 100ml of culture medium. In the absence of a solubilizer, the crude oil was almost insoluble. The concentration of petroleum in the medium was very low, and the petroleum basically hung on the wall of the culture vessel. Although oil is added to the medium, it is not dissolved, so oil plays a minor role

[0009] Most of the existing screening techniques for petroleum-degrading bacteria are based on laboratory research. A single-component petroleum hydrocarbon is used as a substrate to screen bacteria, and then the petroleum hydrocarbon is used as a substrate to evaluate the degradation effect of the screened bacteria. It is only a laboratory-scale bacterial culture, and there are few technical reports on the industrial production of bacterial agents by petroleum-degrading bacteria

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