JP2787015B2 - Fat-and-assimilating bacteria and method of treating fat and oil using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for treating fats and oils, particularly wastewater containing a high concentration of fats and oils, using microorganisms.

[0002]

BACKGROUND OF THE INVENTION Wastewater from meat centers, food processing plants, canteens or homes often contains animal and plant fats and oils.
That process is needed. In particular, since wastewater discharged from a meat center has a high concentration of fats and oils, the fats and oils harden into balls and form sludge-like scum on the surface of the wastewater, causing troubles at pumping stations. For this reason, fats and oils in wastewater are generally separated and removed using a natural levitation device or a pressure levitation device. By such processing, 10 to 20
% Fat remains without being removed and is biologically treated by the activated sludge method or the rotating disk method.

However, separation and removal of fats and oils by natural levitation or pressurized levitation have problems such as maintenance of the apparatus and generation of offensive odors due to spoilage of proteins contained together with the fats and oils. On the other hand, in recent years, from the viewpoint of environmental protection, an apparatus for rapidly reducing organic waste as an organic fertilizer using microorganisms without incineration of garbage has become widespread. However, this device also has a problem such as generation of tar-like substances due to decomposition of animal and vegetable waste oil.

[0004]

In order to solve the above-mentioned problems, a number of biological treatment methods have been developed and there are many reports related thereto, but most of them relate to the treatment of wastewater having a fat concentration of 1% or less. It is. For example, Japanese Unexamined Patent Publication
153922 discloses the decomposition of fats and oils in a wastewater treatment system using Pseudomonas sp. And Acinetobacter sp. In this case, the fat content of the treatment system is only 0.2% (v / v). . Japanese Patent Application Laid-Open No. 6-246295 discloses a method for treating oil-containing wastewater using lipase. In this case, however, the amount of fats and oils that can be treated is less than 1% (v / v).

An object of the present invention is to use wastewater containing a higher concentration of fats and oils or fats and oils per se,
It is an object of the present invention to provide a method for treating a bacterium more rapidly using a thermophilic bacterium, and a thermophilic bacterium.

[0006]

SUMMARY OF THE INVENTION The present invention provides a Burkholderia
A method for assimilating fats and oils, comprising a step of contacting the fats and oils with microorganisms belonging to the genus and capable of aerobically assimilating fats and oils at a high temperature, thereby achieving the above object.

[0007] In a preferred embodiment, the step of contacting the fat or oil is performed at 50 ° C.

[0008] In a preferred embodiment, the initial concentration of the fat or oil is 2% or more.

[0009] In a preferred embodiment, the microorganism is Burkholderia cepacia (FERMP-15034).

[0010] In a preferred embodiment, the microorganism is fixed.

In a preferred embodiment, the above fats and oils are added continuously to maintain a constant concentration.

In a preferred embodiment, the fat or oil is an animal or vegetable fat or oil contained in wastewater.

[0013] The present invention relates to Burkholderia cepacia (FERMP-1503) which utilizes fats and oils.
4), thereby achieving the above object.

[0014] The present invention relates to a Burkholderia.
ia) A fat and oil-containing wastewater treatment device having a device for contacting microorganisms belonging to the genus and capable of aerobically assimilating fats and oils at high temperature with fats and oils contained in wastewater, thereby achieving the above object. You.

[0015]

DETAILED DESCRIPTION OF THE INVENTION

(Explanation of terms) The term "oil" used in the present specification
Refers to glycerin esters of fatty acids, fatty acids, and animal and vegetable so-called fats and oils containing the same, and when these are edible oils, also include those modified by cooking or the like. "Oil-containing wastewater" refers to wastewater containing these oils and fats.

The term "assimilation" includes the breakdown of fats and oils and their assimilation. When the microorganism of the present invention is cultured at a high temperature in a medium containing fats and oils and the fats and oils in the medium are assimilated, the amount of fats and oils in the medium decreases from the amount of the fats and oils in the initial stage.

The terms "high temperature" and "thermophilic bacteria" refer to bacteria that can grow above 40 ° C and above 40 ° C, respectively.
When the microorganism of the present invention is cultured at a high temperature in a medium containing fats and oils, the culture temperature is 40 ° C or higher, and more preferably 40 ° C or higher.
60 ° C, more preferably 48 ° C to 52 ° C, most preferably 50 ° C.

The terms "including fats and oils" and "containing fats and oils"
The term refers to a state in which at least 0.5% or more, more preferably 1.0% or more, and most preferably 2% or more of fat or oil is present in a medium or wastewater.

The term "immobilized microorganisms" means that microorganisms are confined in a certain space or bound to a surface while preventing the assimilation ability of fats and oils from being impaired. Say. The reaction can be continuously performed by immobilization, and can be reused after the reaction.

(Search for Bacteria Utilizing Fats and Oils) It is generally said that the endogenous respiration rate of thermophilic bacteria is much higher than that of normal-temperature bacteria. It is considered that surplus sludge is hardly generated by the treatment of high-concentration organic wastewater by a high-temperature, aerobic method using a thermophilic bacterium. Then, this invention aimed at the fats-and-oils treatment by thermophilic bacteria. First, a test medium was cultured for 3 days in a liquid medium (50 ° C.) containing waste oil, and microorganisms which could sufficiently utilize the oil were searched. As a result, about 10 kinds of bacteria could be isolated. Next, flask culture was performed using a medium containing 3% oil, and the remaining oil was extracted with hexane to quantitatively examine the assimilation rate. As a result, one of them, Burkholderia cepacia (FERMP-1503)
4) Despite its low lipase-producing ability (10 units / ml or less), it was found that the strain was very high in assimilation of fats and oils and was suitable for treating wastewater containing oil.

(1) Morphology and Culture The fungus of the present invention is a fungus isolated from soil. The bouillon medium containing animal and vegetable oils secretes lipolytic enzymes and proliferates.

(Bouillon agar medium) 0.5% polypeptone, 0.5% bonito extract, 0.5% sodium chloride, 2%
% Agar (pH 7.0) was inoculated with the bacterium of the present invention and cultured at 30 ° C. for 24 hours to show the properties observed: Cell shape: Bacillus Gram staining: negative Spore presence: No movement Sex: yes Colony morphology: round, regular, uniform and smooth,
Shiny and slightly convex. Point-like, translucent, smaller than 1 mm in diameter, yellow in color.

The more detailed mycological properties of the fungus of the present invention are as follows: Growth temperature: 15 ° C. to 45 ° C., 40 ° C. when the medium contains fats and oils.
It is possible to grow above.

Catalase: + Oxidase: + OF test:-(oxidative) Nitrate reduction:-Indole formation: none Formation of acid from glucose: none Decomposition of arginine:-Urease:-Esculin decomposition: + Gelatin decomposition: + β-galactosidase: + glucose assimilation: + arabinose assimilation: + mannose assimilation: + mannitol assimilation: + N-acetylglucosamine assimilation: + maltose assimilation: (+) gluconic acid assimilation: + caprate assimilation: + adipic acid assimilation: + Malate assimilation: + Citric acid assimilation: (+) Phenyl acetate assimilation: + Cytochrome oxidase: + Lysine decarbonization: None Tween 80: + Tartaric acid alkalization: + Fluorescent dye King's A:-Fluorescent dye King's B :-Alkalization of acetamide: (+) Quartz in Simmon's medium Utilization of acid: + Levan:-Denitrification reaction: None Alkalinization of asparagine: + Oxidation of gluconic acid:-By having the above microbiological properties, the fat-and-acid assimilating bacterium of the present invention (hereinafter referred to as Is called Burgholderia (Bu
rholderia), a species of Burkholderia cepacia
lderia cepacia).

(Deposit of this bacterium) The bacterium was deposited on July 6, 1995 at the Research Institute of Biotechnology, Industrial Science and Technology, and the deposit number is FERMP-15034.

(Culture of the present bacterium) The present bacterium can be cultured in either liquid culture or solid culture. The medium for growing the present bacterium is not particularly limited, and a usual liquid medium or solid medium is used. Any carbon source can be used as long as it can be assimilated by the bacterium, and sugars such as glucose, sucrose, molasses, starch, and wood flour can be used. As the nitrogen source, an organic nitrogen source such as peptone, yeast extract, malt extract, meat extract, soybean decomposed product, and urea, and an inorganic nitrogen source such as ammonium nitrate and sodium nitrate can be used. If necessary, inorganic salts such as phosphates, magnesium sulfate, potassium sulfate, sodium, calcium, copper, manganese and zinc, vitamins and the like can be added. These medium components may be in any concentration that does not inhibit the growth of the present bacterium, and the carbon source is 0.1 to
20%, preferably 5-10%, nitrogen source 0.01-5
%, Preferably 0.1 to 2%.

The pH of the medium is adjusted to 2.0 to 12.0, preferably 4.0 to 8.0, more preferably 5.0 to 8.0, and used after sterilization. The culture temperature may be any temperature at which a bacterium belonging to the genus Burkholderia can grow. When the medium does not contain fats and oils, the temperature is 10 to 45 ° C., preferably 20 to 40 ° C., and when the medium contains fats and oils. Is 2
8 ° C to 60 ° C, preferably 40 ° C to 55 ° C. When this bacterium is liquid-cultured, aeration culture or shaking culture is desirable. The culturing time varies depending on various conditions, but in the case of aeration or shaking culturing, it is usually preferably 2 to 10 days.

(2) Utilization of fats and oils in the culture solution When the present bacterium is cultured in a medium containing fats and oils, the fat and fat content of the medium is at least 2% or more.

The present bacterium reduces oils and fats in the medium when cultured at a high temperature in a medium containing oils and fats.

The present bacterium can be used after being immobilized, but by using it without immobilization, obstacles such as clogging can be avoided.

The wastewater treatment using the present bacterium is performed by bringing the bacterium into contact with the wastewater containing oils and fats and culturing it at a high temperature. Such a method can be adopted.

(3) Calculation of assimilation rate After the present bacterium was cultured in a medium containing fats and oils, hydrochloric acid was added to the medium to adjust the pH to 4, and the remaining fats and oils were extracted using hexane or ether according to JIS KO102-1985. Calculate the assimilation rate.

(4) Apparatus for treating wastewater containing fats and oils The figure shows an embodiment of an apparatus for treating wastewater containing fats and oils using the present bacteria. FIG. 1 shows an aerobic assimilation tank. The aerobic assimilation tank 2 is for introducing oil / fat-containing wastewater 1 to remove oil, and is a conventional reactor such as a fixed bed utilizing the present bacteria. FIG. 2 shows an oil and fat removing apparatus having a packed bed filled with a carrier on which the present bacteria are immobilized. The fat / oil containing wastewater is sent to the fat / oil removing device 4, and the fat / oil is captured by the immobilization carrier 5. By injecting the air 6 into the device, the fats and oils trapped by the bacteria present in the carrier are aerobically utilized.

The present invention is described in more detail by the following examples, which do not limit the invention in any way.

[0035]

【Example】

(Example 1) Experiment of assimilation of fats and oils with Burkholderia cepacia (1) Peptone 0.5%, meat extract 0.5%, salt 0.1%.
One day (2 days) in a flask containing 100 ml of 5% (pH 7) medium
8 ° C) and 3, 6, 9 g (w /
v%) and forced aeration at 50 ° C. for 3 days. The reduced water was replenished as 0.5% peptone water. Thereafter, hydrochloric acid was added to adjust the pH to 4, and the remaining fats and oils were extracted with hexane according to JIS K0102-1985, and the assimilation rate was calculated.

[0036]

[Table 1]

Example 2 Assimilation of fats and oils was examined in the same manner as in Experiment (1). However, the same amount of waste oil was added every day, for a total of three times.

[0038]

[Table 2]

(Example 3) 8 L for jar fermenter
Medium, and inoculated with a seed bacterium cultured in a flask.
Cultivation for one day, and then, 320 g / day of waste tangle oil,
Peptone was administered at a rate of 8 g / day for 10 days. Meanwhile, tap water was replenished to keep the total volume at 8L.

As a result, the amount of residual waste oil was 416 g with respect to the total amount of waste oil input of 3200 g, and the assimilation rate of fats and oils was 87%.

Example 4 The same experiment as in (1) was performed using beef tallow. However, the remaining beef tallow was extracted using ether instead of hexane.

[0042]

[Table 3]

[0043]

Industrial Applicability According to the present invention, there is provided a genus Burkholderia which has a property of assimilating fats and oils at a high temperature, and a method for reducing fats and oils in wastewater containing fats and oils using the same. This method is Burk
The culture of holderia genus at a high temperature can suppress the growth of other germs, and can treat a much larger amount of fats and oils than the amount of fats and oils conventionally decomposed. Useful for solving problems. The present invention can be widely used in bioreactors for treating wastewater containing oils and fats using the genus Burkholderia of the present invention.

[Brief description of the drawings]

FIG. 1 is a diagram showing an aerobic assimilation tank utilizing the present bacterium.

FIG. 2 is a view showing an oil / fat removing apparatus having a bed filled with a carrier having a Burkholderia genus immobilized thereon.

[Explanation of symbols]

 1. Oil and wastewater 2. Aerobic assimilation tank 3. Treated water 4. Oil removal device 5. Burkholderia bacteria-immobilized carrier 6. air

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuji Shimada 1-6-50 Morinomiya, Joto-ku, Osaka-shi Inside the Osaka Municipal Industrial Research Institute (72) Inventor Yasunori Matsuba 2-824 Asahi, Nishinari-ku, Osaka-shi Shoei Denki (56) References JP-A-8-19970 (JP, A) JP-A-6-322742 (JP, A) JP-A-3-270781 (JP, A) (58) Fields surveyed (Int. Cl. ⁶ , DB name) C02F 3/34 C12N 1/00-7/08 C12R C12S

Claims (9)

(57) [Claims] 1. A method for assimilating fats and oils, comprising the step of contacting the fats and oils with microorganisms belonging to the genus Burkholderia and capable of aerobically assimilating fats and oils at a high temperature. 2. The method according to claim 1, wherein the step of contacting the fat or oil is performed at 50 ° C. or higher. 3. An initial concentration of the fat or oil is 2% or more,
The method of claim 1. 4. The microorganism is Burkholderia cepacia (FERMP-15034),
The method of claim 1. 5. The method according to claim 1, wherein the microorganism is immobilized. 6. The method according to claim 1, wherein the fat is continuously added to keep the fat concentration constant. 7. The method according to claim 1, wherein the fat is an animal or plant fat contained in wastewater. 8. Burkholderia cepacia (FERMP-1503) which assimilates fats and oils at high temperatures.
Four). 9. An oil / fat-containing wastewater treatment apparatus comprising: a microorganism belonging to the genus Burkholderia, which is capable of aerobically assimilating oil / fat at a high temperature, and an apparatus for contacting oil / fat contained in wastewater.