TWI519642B - Novel dekkera bruxellensis - Google Patents

Description

Novel Brussels Dirk yeast

The present invention relates to a process for producing resveratrol, and in particular to a process for producing resveratrol by microbial conversion.

Resveratrol (resveratrol) is a plant polyphenol, mainly caused by environmental stress, such as: external damage, UV over-irradiation. The defense mechanism generated by insects and microbial invasion infections is a phytoalexins (Anastasiadi et al., 2012; Burns et al., 2002; Fremont, 2000; Potrebko and Resurreccion, 2009). The chemical name of resveratrol is 3,5,4'-trihydrozystibene (Abbott et al.), the earliest in 1940 scholar Takaoka by the root of white hellebore (Veratrum grandiflorum O.Loes) The identification was isolated, and then in 1963, the resveratrol component was also isolated from the rhizome of the traditional Chinese herbal medicine Polygonum cuspidatum . In addition to being found in the above plants, resveratrol also exists in certain plants, such as certain berries such as grapes and blueberries, or peanuts and pomegranates (Burns et al., 2002; Counet et al. , 2006; Jerkovic et al., 2010; Manach et al., 2004; Tome-Carneiro et al., 2012; Wang, 2012), however, the resveratrol content of these plants varies widely, and In some plants, resveratrol is present in the form of a glycidid (polydatin).

Resveratrol is currently known to have anti-aging, reduce diabetes, liver The risk of illness, heart disease, cancer and other metabolic syndrome-related diseases, however, due to its low content in plants and difficult extraction, its price and application are limited.

Resveratrol compounds have two isoforms, cis and trans, respectively. The trans structure has physiological activity, and the trans structure becomes cis-structure and loses its physiology after UV irradiation. Activity (Potrebko and Resurreccion, 2009), in plants, resveratrol binds to sugars to form a more stable glycoside form, with glycosides in different positions (Counet et al., 2006; Jerkovic et al., 2010) ; Sun et al., 2010; Wang et al., 2007; Zhang et al., 2007), also in the form of two monosaccharides, but in the knotweed, the monosaccharide is mainly attached to the 3'-position. The hydroxy form is predominant (Sun et al., 2010; Wang et al., 2007; Wu Jiaying, 2007). These different forms of glycosylation are mainly to stabilize resveratrol in living organisms, and the organism can be directly transformed at an appropriate timing. Generate resveratrol application.

At present, the methods for producing resveratrol include plant extraction, chemical synthesis, plant transformation, and microbial genetic engineering. However, resveratrol in plants is mainly synthesized by tyrosine and phenylalanine pathways. The step is to synthesize stilbene synthase (Donnez et al., 2009). The current literature lists microbial genetic engineering to produce resveratrol, which can be divided into yeast and bacteria (Donnez et Al., 2009).

Literature research indicates that there are currently five methods for extracting resveratrol from Polygonum cuspidatum, which are Alkaline extraction, Solvent extraction, Ultrasonic extraction, and cable reflux extraction. Soxhlet extraction) and CO ₂ supercritical fluid extraction (SFE-CO2) (Benova et al., 2010; Cho et al., 2006; Du et al., 2007; Lei et al., 2007; Wu Jiaying, 2007). All extraction methods have their advantages and disadvantages, but ultrasonic extraction is the best in terms of extraction (Lei et al., 2007).

The present invention provides a method for producing resveratrol by microbial transformation, comprising: (a) providing a yeast of the genus Dekkera or a mutant thereof and a substrate, wherein the substrate comprises a white gourd An alcohol precursor or a plant substrate comprising a resveratrol precursor; (b) adding the yeast of the genus D. cerevisiae or the mutant thereof to the medium to form a mixture; and (c) The mixture is subjected to fermentation such that the resveratrol precursor present in the mixture is biotransformed by the yeast of the genus Dacillus or a mutant thereof to produce resveratrol.

The present invention also provides a novel mutant strain of Dekkera bruxellensis , which was deposited on January 9, 102, in the Center for Biological Resource Conservation and Research of the Republic of China Food Industry Development Institute, under the registration number BCRC 920084. Brussels Dick yeast.

Figure 1A shows the results of experiments in which the initially selected strains were transformed with polygonum cuspidatum to form resveratrol.

Figure 1B shows the experimental results of the initial selection of each strain using pomegranate peel as a substrate to produce resveratrol.

Figure 2 shows the results of experiments in which different D. brucei were converted to resveratrol using the Polygonum cuspidatum substrate.

Figure 3 shows the amount of β-glucosidase produced by the 12 mutant strains selected at different culture time points.

Figure 4A shows the use of a 5 liter fermenter with a Polygonum cuspidatum as the plant substrate and culture of the No. 72 mutant with water, acetic acid buffer solution or Vogel minimal salts medium (VMSM) for the white squash. The result of alcohol conversion.

Fig. 4B shows the results of reconstitution of resveratrol by using a 20 liter fermentation tank and using a Polygonum cuspidatum as a plant substrate and culturing a mutant strain No. 72 with an acetic acid buffer solution.

In one embodiment of the invention, the invention provides a method for the production of resveratrol by the above microorganisms. The method for producing resveratrol by microbial transformation of the present invention may include the following steps, but is not limited thereto.

First, a yeast of the genus Dekkera or a mutant thereof and a substrate are provided. The above substrate may include, but is not limited to, a resveratrol precursor or a plant substrate containing a resveratrol precursor.

The yeast of the genus Decobacteria or a mutant thereof may include, but is not limited to, Dekkera bruxellensis or a mutant thereof. Examples of the above-mentioned D. cerevisiae or a mutant thereof may include, but are not limited to, D. brucei BCRC 21440 or a mutant thereof. Further, examples of the mutant strain of D. brucei BCRC 21440 may include, but are not limited to, deposited in the Bioresource Conservation and Research Center of the Republic of China Food Industry Development Institute on January 9, 102, the registration number of BCRC 920084 of D. serrata and the like.

In one embodiment, the yeast of the genus D. cerevisiae or the mutant thereof used in the method for producing resveratrol by microbial transformation of the present invention may be D. brucei BCRC 21440. In another embodiment, the yeast of the genus Dirkweed or the mutant thereof used in the method for producing resveratrol by microbial transformation of the present invention may be deposited on January 9, 102, the Republic of China. Bioresource Conservation and Research Center of the Republic of China Food Industry Development Institute, registered D. serrata of BCRC 920084 (this bacterium was also deposited with the German Collection of Microbial Species on July 11, 2013 (Deutsche Sammlung von Mikroorganismen und Zellkulturen, DSMZ), registration number DSM 27483).

In the method for producing resveratrol by microbial transformation of the present invention, the above resveratrol precursor may include resveratrol glycoside or the like, but is not limited thereto, and examples of the resveratrol glycoside may include, but not Limited to Polygonum glycosides and the like. Further, in the method of the present invention for producing resveratrol by microbial transformation, examples of the plant substrate containing the resveratrol precursor may include, but are not limited to, knotweed, grape or grape skin, pomegranate or pomegranate peel. , peanuts, cocoa, blueberries, mulberries, cranberries or bolognese. In one embodiment, the plant substrate containing the resveratrol precursor may be a Polygonum cuspidatum, and the resveratrol glycoside contained in Polygonum cuspidatum is a Polydatin.

In a particular embodiment, in the method of the invention for producing resveratrol by microbial transformation, the substrate is a plant substrate comprising a resveratrol precursor. Further, an example of a plant substrate containing a resveratrol precursor in this embodiment may be a knotweed.

Next, after providing a yeast of the genus Decobacterium or a mutant thereof and a substrate, the above-mentioned yeast of the genus D. cerevisiae or a mutant thereof and the above-mentioned substrate It is added to a medium to form a mixture.

The yeast of the genus Decobacteria or a mutant thereof is added in an amount of from 1 to 65% by volume of the medium. In one embodiment, the yeast of the genus Decobacteria or a mutant thereof is added in an amount of from 1 to 40% by volume of the medium. Further, the substrate is added in an amount of from 1 to 65% by volume of the medium. In one embodiment, the substrate is added in an amount of from 1 to 40% by volume of the medium.

Further, examples of the medium suitable for the present invention may include, but are not limited to, water, an acetic acid buffer solution, and a Vogel minimal salt medium (VMSM).

Then, after the above-mentioned yeast of the genus D. cerevisiae or the mutant thereof is added to a medium to form a mixture, the mixture is fermented so that the resveratrol precursor present in the mixture is obtained by the above-mentioned German The yeast of the genus Saccharomyces or its mutant is biotransformed to produce resveratrol.

The fermentation can be carried out for a period of about 12 to 72 hours. In one embodiment, the fermentation can be carried out for a period of from about 18 to 48 hours. Further, the above fermentation can be carried out at a temperature of about 20 to 35 °C. In one embodiment, the above fermentation can be carried out at a temperature of about 23-30 °C.

Alternatively, the above fermentation can be carried out in a shake flask or fermentation tank.

In one embodiment, in the method for producing resveratrol by microbial transformation according to the present invention, the fermentation is carried out in a fermenting tank, and the yeast of the genus Decobacter is added in an amount of 1-65% by volume of the medium. And the substrate is added in an amount of from 1 to 65% by volume of the medium. In still another embodiment, the fermentation may be carried out for a period of about 18 to 48 hours, and the fermentation may be carried out at a temperature of about 23 to 30 °C. Further, in this embodiment, the substrate is the plant substrate containing the resveratrol precursor, and the plant substrate It can be a knotweed or a pomegranate peel.

Furthermore, in another embodiment, the present invention uses a method for microbial conversion to produce resveratrol, and the mixture is fermented as described above so that the resveratrol precursor present in the mixture is subjected to the above-mentioned D. After the step of biotransformation of the yeast or its mutant to produce resveratrol, a step of extracting resveratrol from the mixture may be further included.

The above step of extracting resveratrol from the mixture may include the following steps, but is not limited thereto.

Alcohol is first added to the above-mentioned post-fermentation mixture and subjected to ultrasonic vibration to form an extract. The above alcohol may include 1-80% alcohol, and in one embodiment, the above alcohol is 80% alcohol. Further, the volume ratio of the alcohol used to the above mixture is 1:5-1:20. In one embodiment, the volume ratio of alcohol used to the above mixture is 1:10.

Next, after the formation of the above extract, the above extract was dried, and then water and diethyl ether were further added to form an aqueous layer and a diethyl ether layer. The weight ratio of water used to the above dried extract is 1:5-1:20. In one embodiment, the weight ratio of water used to the dried extract described above is 1:10. Further, the weight ratio of the diethyl ether to the above-mentioned dried extract is 1:5-1:20. In one embodiment, the weight ratio of diethyl ether used to the dried extract described above is 1:10.

Then, the above ether layer was collected and the above ether layer was dried to obtain a resverat product.

In addition, in another embodiment of the present invention, the present invention provides a novel mutant strain of D. brucei, which was deposited on January 9, 2003 in the Republic of China Food Industry Development Institute for biological resources conservation and researching Heart, registered D. serrata, BCRC 920084.

Example

A. Materials and methods

(A) material

1. Standard product:

Resveratrol and glycosides were purchased from Aldrich.

2. Reagents and culture media:

Yeast extract peptone dextrose medium (YPD), acetic acid, sodium acetate, ethanol, chloroform, ethyl acetate, benzene ), ethyl ether, toluene, hexane, acetonitrile, pNP, pNPG, NaCl, NH ₄ Cl, Na ₂ CO ₃ , glucose, maltose, lactose ( _{lactose), KNO 3, NH 4} NO 3, (NH 4) 2 SO 4, aspirate yeast (yeast extract), peptone _{(peptone), MgSO 4, KCl} , Tween 80 , etc. available from the company Merck.

3. Instrument

Incubator of various temperatures, electromagnetic heating stirrer, high-performance liquid chromatography (HPLC), spectrophotometer, 5 liter fermentation tank, 20 liter fermentation tank, freeze dryer, cyclone concentrator, large steam Concentrator, frame filter press, vertical filter press, etc.

(B) method

1. Shake flask culture:

The bacteria were inoculated into a yeast extract peptone glucose medium, and cultured at 150 rpm and 25 ° C to form a bacterial solution. When the OD ₆₀₀ value of the bacterial solution reaches 10, in the medium (for example, acetate buffer (1M ~ 5mM, pH 4.5 ~ 6.5)), the above bacterial solution (added amount is 5% of the medium volume) and chalk A ruthenium precursor or a plant substrate containing a resveratrol precursor (added in an amount of 5% by volume of the medium) was subjected to fermentation at 150 rpm, 25 ° C for 24 hours. After the culture solution was lyophilized and extracted with 80% alcohol, the glycosidic and resveratrol contents were analyzed by high performance liquid chromatography.

2. Determination of β-glucosidase activity of the strain

(1) pNP was formulated into different concentrations with 1 M Na ₂ CO ₃ , and the absorbance of each concentration of pNP at OD 405 nm was measured spectrophotometrically as a calibration curve.

(2) The strain to be tested is cultured and sampled and analyzed at different times.

(3) Dividing the bacterial liquid into two parts. After a part of the enzyme was deactivated by heating at 100 ° C for 5 minutes, it was cooled and centrifuged, and 1 mL of the supernatant was taken to a transparent glass tube as a blank control group; and the other part was centrifuged and 1 mL of the supernatant was taken to a transparent glass tube as an experimental group.

(4) The control group and the experimental group were separately added with 10 mM of pNPG (dissolved in 20 mM acetate buffer, pH 5) 1 mL, followed by heating at 50 ° C and stirring for 30 minutes to carry out a reaction to form a reaction solution. Thereafter, 2 mL of ice 1 M Na ₂ CO ₃ was added to the reaction solution to terminate the reaction. Then, after the reaction solution was uniformly mixed, a part thereof was measured for its absorbance at OD 405 nm. If the measured absorbance exceeds the range of the calibration curve, the control is diluted and measured, and the enzyme activity is pushed according to the calibration curve.

3. N-methyl-N ' -nitro-N-nitrosoguanidine (NTG) mutation

According to previous experiments, it was found that the strain was treated with 100 ppm of methylnitronitrosoguanidine for 5 minutes to produce a mutation with better results, so that Dekkera bruxellensis BCRC 21440 was first treated with different concentrations of methyl nitrate. The nitrosoguanidine was treated for 5 minutes to generate a mutation. The results showed that the lethality rate of D. cerevisiae BCRC 21440 treated with 100 ppm of methylnitronitroguanidine for 5 minutes was about 58%. The D. sclerophylla BCRC 21440 was then re-treated with 100 ppm of methylnitronitroguanidine for various lengths of time. The results showed that the mortality of the strain increased with the increase of the treatment time of methylnitronitroguanidine. After 20 minutes of treatment, the lethality of the strain reached 70%, but then the mortality rate slowed down as the treatment time prolonged. In addition, different concentrations of methylnitronitroguanidine were reconfigured and D. brucei BCRC 21440 was treated with different concentrations of methylnitronitroguanidine for 5 minutes for mutation. The results showed that as the concentration of methylnitronitroguanidine increased, the lethality of the strain increased. When the concentration of methylnitronitroguanidine was 300 ppm, the lethality of the strain reached 70%, but then the mortality rate slowed down as the treatment concentration increased.

The experimental method of methylnitronitroguanidine mutation is as follows: (i) activation of the strain; (ii) transfer of the activated strain to the culture solution; (iii) culture for 16-24 hours, culture at 8000 rpm The solution was centrifuged for 5 minutes to collect bacteria; (iv) the supernatant was removed, and the precipitate was washed back three times with an equal amount of PBS buffer solution; (v) the concentration of the bacterial solution was adjusted to about 10 ⁶ CFU/mL; (vi) Mixing the bacterial solution with methylnitronitroguanidine (different concentrations of methylnitronitroguanidine or different treatment time); (vii) centrifuging the bacterial liquid to remove the supernatant, and then depositing the precipitate An equal amount of PBS buffer solution was washed 3 times; (viii) the bacterial solution was diluted in an appropriate amount and applied to the plate medium for culture; (ix) the strain was selected for its β-glucosidase activity assay; The strain with better β-glucosidase activity is further mutated or subjected to stability analysis.

The selected methylnitronitroguanidine-treated mutant was adjusted to the bacterial concentration, and then inoculated into a 96-well ELISA plate and cultured for 24 hours. Then, the supernatant was taken out and added with pNPG and Na ₂ CO ₃ color, and the value of OD 405 nm was read by an ELISA reader, and this value was compared with the original strain to select β-glucosidase production. A better strain. The strain with better β-glucosidase yield was analyzed by ELISA reader for β-glucosidase stability. If the same sample was measured multiple times, the ELISA reading value was stable, indicating that the strain was secreted and secreted. The β-glucosidase trait is stable.

4. Preparation of plant substrate, microbial conversion production of resveratrol and calculation of conversion rate

(1) Plant bases such as Polygonum cuspidatum and pomegranate peel are grounded in a juice machine for use.

(2) The strain was activated with yeast extract peptone glucose medium. The strain is then added to the plant-containing substrate medium to allow the matrix to be transformed, and samples are collected at different time points.

(3) The sample was lyophilized, followed by addition of 50% ethanol and ultrasonically assisted extraction at 70 ° C for 30 minutes. The extracted extract was cooled and filtered through a 0.22 um filter.

(4) The content of piceid and resverotrol in the filtrate was analyzed by high performance liquid chromatography, and the conversion rate of polydatin to resveratrol was calculated.

M: Moir number

5. Extraction of resveratrol:

(1) The lyophilized medium containing the transformed plant substrate was added to 1:10 of 80% alcohol (w/w) and subjected to ultrasonic (40 kHz) shaking for 30 minutes. Two extractions were carried out in this step; (2) the extracts were combined and dried. The solution was formed by water (w/w) at 1:10, and then diethyl ether was added to the solution in a ratio of 1:1, and then the ether layer was collected, and the extraction was carried out twice; (3) the ether layer was dried. Resveratrol product.

6. Analysis of glycosides and resveratrol:

(1) Take the glycosidic and resveratrol standards, respectively, and prepare them at concentrations of 0.5, 5, 25, 75, 100, 150 and 175 mg/L with 50% alcohol and analyze them by HPLC to obtain their respective The calibration curve; (2) diluting the sample after extraction into the concentration of the calibration line, filtering with 0.22 μm filter, analyzing the content of resveratrol and glycoside by HPLC; (3) HPLC analysis with C ₁₈ column 4.6×250 nm 5 μm (Waters ODS II) was analyzed as a separation column; (4) the mobile phase was A: 0.1% acetic acid; B: acetonitrile. Initially with 95% A and 5% B, after 25.3 minutes, it is converted to 55% A and 45% B, 31 minutes to 100% B, and after 33 minutes, the initial value is 95% A and 5% B , maintained to 45 minutes; (5) mobile phase flow rate of 1.5mL / min, sample injection volume of 20μL.

B. Experiments and results

1. Analysis of the ability of strain transformation matrix to produce resveratrol

(1) Preliminary screening of strains

Firstly, preliminary screening was carried out by the microbial resource pool of the Biomass Center, and the bacteria, yeast and filamentous fungi as shown in Table 1 were initially screened. They were separately cultured and tested for β -glucosidase activity.

After measuring the β-glucosidase performance of each strain, a strain of microorganisms exhibiting high β-glucosidase was selected, which were respectively 2 yeasts, which were Dekkera bruxellensis BCRC 21440 and brewed with beer. Saccharomyces cerevisiae BCRC 20855 , and 9 strains of fungi, Aspergillus niger BCRC 32734 and BCRC 30883, Stemphylium loti BCRC 31890, Myrothecium verrucaria BCRC 31545, Aspergillus oryzae BCRC 30230 and BCRC 32271, and Sporotrichum thermophile BCRC 31852.

2. Analysis of the ability of strain transformation matrix to produce resveratrol

The following experiments were carried out for each of the selected strains. A powder of a Polygonum cuspidatum or pomegranate peel as a plant substrate and a strain are added to water and fermented. After the fermentation, the culture solution was added to 80% ethanol for extraction. The obtained extract was analyzed for the content of resveratrol and glycoside by HPLC. The experimental results of each strain using the Polygonum cuspidatum as the substrate are shown in Fig. 1A, and the experimental results of the respective strains using the pomegranate peel as the substrate are shown in Fig. 1B.

According to the results of Figures 1A and 1B, it can be clearly seen that the same strain has different ability to increase or decrease the resveratrol and glycoside content of different plant substrates, and different strains for the same plant substrate of white gourd The increase and decrease of alcohol and glycoside content are also different. According to the results of the whole experiment, it is preliminarily that the yeast Dekkera bruxellensis BCRC21440 has a better effect of transforming resveratrol to produce resveratrol.

3. Analysis of the ability of different transformation substrates of Dekkera bruxellensis strain to produce resveratrol

The results of the above-mentioned strain transformation test showed that the yeast D. cerevisiae BCRC 21440 had a better effect of producing resveratrol for the production of resveratrol, and therefore attempted to collect different strains of D. serrata, They are D. brucei BCRC 21440, D. serrata BCRC 20932, D. serrata BCRC 21518, D. serrata BCRC 21519 and D. serrata BCRC 21517, and the collected strains The test of transforming resveratrol with Polygonum cuspidatum as a plant substrate. The conversion results are shown in Figure 2.

According to Fig. 2, the collected D. serrata has a good ability to transform the matrix to produce resveratrol for the Polygonum cuspidatum substrate, and the subsequent mutation with D. brucei BCRC 21440 strain to enhance its transformation matrix production. The ability of resveratrol.

The content of glycosides in Polygonum cuspidatum is about 2-4 times higher than that of resveratrol, which is much higher than other plant substrates. Therefore, using Polygonum cuspidatum as the plant substrate transformed by the strain can obtain better yield of resveratrol and facilitate subsequent purification. Resveratrol is recovered.

4. N-methyl-N ' -nitro-N-nitrosoguanidine (NTG) mutation of Dick's yeast BCRC 21440

A total of 226 mutant strains were selected and analyzed by a series of NTG mutations. The results of 12 strains were better, which were number 11, 16, 34, 39, 41, 53, 58 respectively. The mutants of 61, 63, 67, 70 and 72 were further analyzed for the amount of β-glucosidase produced by the 12 mutant strains at different culture time points. The result is shown in Figure 3.

According to Fig. 3, the β-glucose of the above 12 mutant strains is known. The glycosidase yield was better than that of the original strain, and the mutant strains numbered 11, 53, 61 and 72 were preferred.

Thereafter, the β-glucosidase produced by the mutants of the above Nos. 11, 53, 61 and 72 was subjected to stability analysis. After selecting 23 colonies per plant and adjusting to the same OD value, the cells were cultured for 48 hours. Thereafter, the OD ₄₀₅ absorbance of the cultured bacteria was measured, and the stability was analyzed. The results showed that the ability of the four strains to produce β-glucosidase was not much different, while the mutant strain No. 11 had a greater variability in the production of β-glucosidase (>10%), and the other three strains were all below 10%. Since the β-glucosidase production of the No. 72 mutant was slightly higher, it was used as a strain for the subsequent medium, and it was named Dekkera bruxellensis NTG-72, and it was in the Republic of China. Deposited at the Bioresource Conservation and Research Center of the Republic of China Food Industry Development Institute on January 9, 102, with the registration number BCRC 920084, and deposited at the German Collection of Microbial Species (Deutsche Sammlung von Mikroorganismen und) on July 11, 2013 Zellkulturen, DSMZ), registration number DSM 27483.

Analysis of the ability of the transformed substrate of continuous culture to produce resveratrol

Subsequent experiments were carried out with the above-mentioned No. 72 mutant strain through a series of screening and mutation screening. The inoculum activation was carried out in YPD medium, and then the activated inoculum was inoculated and cultured, and when it was measured at an OD ₆₀₀ of 10, a subsequent transformation test was carried out.

(1) Continuous fermentation of a 5 liter fermentation tank

The mutant strain No. 72 was cultured using a 5 liter fermenter and using Polygonum cuspidatum as a plant substrate to produce resveratrol, and the culture conditions were: 25 ° C, 100 to 200 Rpm, aeration volume of 1 vvm, 5% inoculation amount (relative to the body base of the medium). 2% Polygonum cuspidatum (relative to the body base of the medium) was added as a medium for conversion of resveratrol with Vogel minimal salts medium (VMSM), 20 mM acetate buffer pH 5.0 and water as the production medium. The plant substrate was used to culture the mutant No. 72, and the results are shown in Fig. 4A.

Figure 4A shows that the highest yield of resveratrol was obtained with acetate buffer as the medium. Highest concentrations of resveratrol of 7455.6 μ g / g, and then gradually decreases with increasing time, but this time only the content of glycosides Polygonum 198.6 μ g / g, and followed by water as a medium, the worst For Fogel's smallest salt medium.

(2) Continuous fermentation of 20 liter fermentation tank

The mutant strain No. 72 was cultured using a 20-liter fermentation tank and a Polygonum cuspidatum as a plant substrate to produce resveratrol, and cultured at 100-200 rpm and 0.2 vvm. 20 mM acetate buffer pH 5.0 was used as the medium, and 2% of Polygonum cuspidatum (relative to the body base of the medium) was added as a substrate, and the results are shown in Fig. 4B.

Figure 4B shows that resveratrol content increased over time, tended to be flat until 40 hours, increasing from 2177.6 ug/g to a maximum of 7266.4 ug/g, while the trend of polydatin was reversed. In addition, the conversion rate of polydatin to resveratrol was calculated, and the conversion rate was 95% or more.

Based on the above results, it was found that a yeast having a high yield of β-glucosidase (a mutant strain No. 72) was fermented with Polygonum cuspidatum as a plant substrate to transform a polydatin to form resveratrol. The initial conversion rate of the shake flask, the test speed of the 5 liter fermentation tank and the aeration parameter, and the conversion rate of the 20 liter fermentation tank test amplification process are all possible, including multiple fermentations (including 5 liters, 20 liters, 250 liters, and 2000). The liters are carried out more than three times). The results show that in all experiments of fermentation volume, in culture During the 30-72 hour period, the glycoside content decreased to 0.5 mg/g or less, and resveratrol gradually stabilized after 30 hours, about 8-12 mg/g, and the conversion rate was 95%. the above.

【Biomaterial Storage】

Domestic registration information [please note according to the registration authority, date, number order]

Center for the Conservation and Research of Biological Resources of the Republic of China Food Industry Development Institute, 102/1/9, BCRC 920084 (the registration certificate has been filed in the parent of this application, application number 103107359)

Foreign deposit information [please note according to the registration authority, date, number order]

German microbial strain preservation center (Deutsche Sammlung von Mikroorganismen und Zellkulturen, DSMZ), 2013/7/11, DSM 27483 (the proof of deposit has been filed in the application of this application, application number 103107359)

Claims (1)

A novel D. serrata, deposited in the Bioresource Conservation and Research Center of the Republic of China Food Industry Development Institute on January 9, 102, and registered D. serrata, BCRC 920084.