CN102197861A

CN102197861A - Use of candidaversitijis for removing aflatoxin B1 in high salinity environment

Info

Publication number: CN102197861A
Application number: CN2011100040077A
Authority: CN
Inventors: 周荣清; 李从虎; 黄著; 黄钧
Original assignee: Sichuan University
Current assignee: Sichuan University
Priority date: 2011-01-11
Filing date: 2011-01-11
Publication date: 2011-09-28
Anticipated expiration: 2031-01-11
Also published as: CN102197861B

Abstract

The invention relates to a strain of candidaversitijis, which can effectively remove aflatoxin B1 (AFB1) in a high salinity environment. Use of the candidaversitijis for removing the AFB1 in high salinity environment is characterized by: culturing a strain of activated candidaversitijis provided by the present invention in a malt wort liquid medium until the candidaversitijis is in a early logarithmic growth phase, then inoculating the resulting candidaversitijis in a high salinity liquid material system added the purified AFB1 toxin or a high salinity semisolid material system contaminated by the AFB1 to remove the AFB1; further inoculating the resulting candidaversitijis in a bean sauce contaminated by the AFB1, and culturing the bean sauce inoculated the candidaversitijis in a simulated factory environment. With the present invention, removing rate of the AFB1 through the candidaversitijis reaches 20.15%. The candidaversitijis provided by the present invention can be applicable for the traditional brewing industry, especially the condiment industry with the high salinity environment, and has good economic benefit and practical application value.

Description

AFB is removed in one strain in hypersaline environment 1The use of candidiasis

Technical field

The present invention relates to a strain and in hypersaline environment, remove AFB ₁Candidiasis, on April 29th, 2010 in China Committee for Culture Collection of Microorganisms common micro-organisms center (CGMCC) preservation, deposit number is CGMCC No.3790, belongs to microorganism field.

Background technology

Aflatoxin (AFT) is a class chemistry mechanism similar compounds, is the derivative of dihydrofuran cumarin.Aflatoxin be by aspergillus flavus ( Aspergillus flavus) and aspergillus parasiticus ( Aspergillus parasiticus) wait the secondary metabolite of generation, mainly be present in soil, animals and plants are in various nuts, particularly peanut and the walnut.Soybean, paddy, corn, macaroni, flavouring, milk, dairy produce is also often found aflatoxin in the edible wet goods goods.Aflatoxin is AFB especially ₁(hereinafter to be referred as AFB ₁) have stronger carcinogenesis, therefore, there is strict limitation standard various countries to its content in food, feed.

The measure of removal aflatoxin at present has a variety of, mainly comprises physical method, chemical method, biological method and enzymatic isolation method.Physical method mainly contains (1) and selects mould grain, and milling processing is washed by rubbing with the hands repeatedly; (2) absorption method: adsorbent commonly used has zeolite, alukalin, active carbon etc., when selecting endotoxin adsorbent, should notice that adsorption capacity must possess the laboratory and the dual data of zoopery can prove effectively on the one hand, consider the height adsorption capacity of adsorbent on the other hand.(3) radiation treatment: aflatoxin shines unstable under ultraviolet light, detoxification under the available UV-irradiation.Chemical method has (1) alkali treatment method: the lactonic ring of aflatoxin can be destroyed by alkali, forms the cumarin sodium salt; (2) organic solvent extractionprocess: aflatoxin is soluble in organic solvent, and available organic solvent extracts separation, detoxification; (3) oxidation removal method: oxidants such as bleaching powder, chlorine, hydrogen peroxide, ozone can be rapidly with the aflatoxin oxidation removal; (4) Chinese herbal medicine detoxification: China in 1976 finds that first the volatile oil in the fruit of a cubeb litsea tree can thoroughly remove the aflatoxin in the food.Some composition and aflatoxin in the volatile oil react, and change the structure of toxin, thereby reach the purpose of detoxification.Biological method is to reach the purpose of removing aflatoxin by action of microorganisms.Enzymatic isolation method is to utilize the selectivity of enzyme to reach the purpose of removing aflatoxin.

The objective of the invention is by a kind of microbiological method, separation screening obtains the candidiasis (deposit number is CGMCC No.3790) that a strain has than high-salt tolerance (it has the higher speed of growth under 6%～12% salt content) and is applied to AFB ₁Removal and biological restoration, this bacterial strain belongs to the probio class, not only can remove the AFB that pollutes in the sample ₁, and can improve the fragrance ingredient of product; Simultaneously, the present invention has proved the removal effect of this bacterial strain from actual production.

Summary of the invention

In order to reduce AFB ₁To the harm of humans and animals, reduce the pollution of mycotoxin to the traditional fermentation flavouring, guarantee food security, this paper is applied to AFB in the actual production with this bacterial strain ₁Biological restoration, AFB ₁Clearance reach 20.15%.

Technical problem to be solved by this invention provides a strain and removes AFB ₁Effect is candidiasis and at AFB preferably ₁Application on the contaminated samples.

The present invention require candidiasis ( C. versatilis) cell age be in and be the logarithm initial stage, the concentration of cell concentration in using object is 1.0 * 10 ⁶～3.0 * 10 ⁶Cfu/g (ml) is in wet basis.

The present invention removes AFB ₁Concrete grammar be: in pending soy sauce wine with dregs, beans sauce unstrained spirits or the thick broad-bean sauce unstrained spirits inoculation cell age be the logarithm initial stage candidiasis ( C. versatilis) suspension, initial cell concentration is 1.0 * 10 ⁶～3.0 * 10 ⁶Cfu/g (ml), in wet basis, mixing is placed on 25 ℃～35 ℃, ferments 10～30 days.

The present invention has following advantage:

1, the inventive method can effectively be removed AFB in hypersaline environment ₁, clearance reaches 20.15%.The present invention uses the Candida fungus strain to come from the soy sauce wine with dregs, is oriental traditional brewing seasonings microorganism fungus kind commonly used, and is safe through method validations such as Ames experiments.

2, the inventive method is to adopt to be fit to the salt-durable microbe bacterial strain that high salt fermented seasonings is produced, and removes AFB in the production process ₁Pollution, for its safety in production provides a kind of feasible, reasonable method.

The specific embodiment

Below in conjunction with the concrete example of implementing, further set forth the present invention.Should be understood that these embodiment only to be used to the present invention is described and be not used in and limit the scope of the invention.

Embodiment 1 removes AFB in the liquid material system of high salt ₁

In containing the malt juice liquid medium of 12%NaCl, add AFB ₁, make its concentration arrive 10ng/ml, the access candidiasis ( C. versatilis) suspension, initial cell concentration 1.0 * 10 ⁶Cfu/ml, nonvaccinated sample compares, place 30 ± 2 ℃ incubator to cultivate 72hr, and sample analysis, candidiasis of the present invention have been removed in the sample 52.97% AFB ₁

Embodiment 2 removes AFB in high salt semisolid material system ₁

To produce the bacterial strain of aflatoxin As3.4408(common micro-organisms research institute of the Chinese Academy of Sciences orders) be starting strain, be that raw material is produced the lobe song with the broad bean lobe, adopt the thick broad-bean sauce production technology to add salt solution and make its salt be divided into 13.5%, moisture is 55.0%.With in advance the breeding enter the logarithm initial stage candidiasis ( C. versatilis) suspension access lobe unstrained spirits, initial cell concentration is 1.0 * 10 ⁶Cfu/g (ml) places 30 ± 2 ℃ of incubator heat insulating culture 30d, AFB in the lobe unstrained spirits ₁The rate of removing reach 55.65%.

Embodiment 3 employing this method are removed the AFB in the contaminated sample ₁

With a certain amount of AFB that polluted ₁Thick broad-bean sauce be research object.With breed in advance candidiasis to the logarithm initial stage ( C. versatilis) thick broad-bean sauce that suspension insert to pollute, initial cell concentration is 1.0 * 10 ⁶Cfu/g (ml), simulation plant produced environment is cultivated 30d, AFB down for 25 ℃～35 ℃ ₁The rate of removing reach 20.15%.

The 26SrDNA sequence is:

TTACGCCAACATCCTTGCATAAAGCGCGGTCCTCAATCCCGCCGGGACGTATTTGATAAAGCTATAACACATTCGAAAATGCCACTTTCTTTACCATTTA TCCATCCGGCAAAACTGATGTTAGCCCCTTCCGAAGAAGGTGTGTAGCTTTAAGCCCTTCCACTTCAACGATTTCACGTGCTATTTCACTCTCTTTTCA A AGTGCTTTTCATCTTTCCTTTACAGTACTTGTTCGCTATCGGTCTCTCGCCAATATTTAGCCTTAGATGGAATTTACCACCCACTTAGCGCTGCATTC CC AAACAACGCGACTCGTAGAAAGAGTACTACACAGACACAGGACCTCCGTGGCACGGGGCTATCACCCTCCAAGGCGCGGCTTTCCAGCCAACTTCCA CAG AGCTGAGTCCAGCACTCCATCTCCAAATTACAACTCCTCAAAAGAGGATTTCAAATTTGGGCTTTTGCCGCTTCACTCGCCGTTACTAGGGCAATC

The ITS regional sequence:

TTCAGCGGGTAGTCTTGCCTGATACGAGGTCTTTTAAAGAAAGCTTGGTGTACAAGTTTCACTAACGTGTACATCTCCATTCTTTTCGACACTCTGCATAGCGTCAGCAACCACCATTGGTGAGAAAGATAGACGCTCGCACAGGCATGCTGTTAGGAGAACCTAACAGCGCAATGTGCGTTCAAAGATTCAATGACTCACGTCTGCAATTCGCATTACCTATCGCGCTTTGCTGCGTTCTTCATCGATGCGAGAACCGAGAGATCCGTCGTTGAAGCTTGTATAATTTATAGTTAATCTGAATAAATAATAATGGTTGAGTTTTGTATGATTGGCGGCTTGCTATAAAAGCGCCCCGCCAAAACACAATGAGAAGGTTCACAGAAATGTGATAGTAATCTCAGAAATGATCCTTC。

Claims

1. a strain salt tolerance candidiasis is applied to AFB in the traditional fermentation flavouring ₁(AFB ₁) removal, its content comprises: at first strain culturing of the present invention to the cell age with activation is the logarithm initial stage, is applied to AFB in liquid material system of high salt and the soft solid materials system then respectively ₁Removal, initial cell concentration is 1.0 * 10 ⁶～3.0 * 10 ⁶Cfu/g (ml) is applied to bacterial strain of the present invention in the actual production at last, proves the feasibility of this bacterial strain practical application.

2. require Liquid Culture based formulas of the present invention to be according to right 1:

Candidiasis fluid nutrient medium (malt juice liquid medium):

6～10Be ° of brewer's wort liquid, 12%NaCl, pH5.0～5.5.

The candidiasis that screening obtains according to the described method of claim 1 ( C. versatilis), deposit number is: CGMCC No.3790.

According to the candidiasis of claim 1 ( C. versatilis) application, the present invention is applicable in all kinds of traditional fermentation products, as bean cotyledon, fermented bean curd, fermented soya bean etc.

5. according to right 1 requirement, the AFB that removes of the present invention ₁Method, it is characterized in that: be used to remove AFB ₁The cell age of bacterial strain of the present invention be the logarithm initial stage, be inoculated into by AFB ₁Candidiasis in soy sauce wine with dregs, beans sauce unstrained spirits or the thick broad-bean sauce unstrained spirits that pollutes ( C. versatilis), its initial cell concentration is respectively 1.0 * 10 ⁶～3.0 * 10 ⁶Cfu/g (ml), in wet basis, the fermented and cultured temperature is 25 ℃～35 ℃, incubation time is 10d～30d.