阅读说明：本技术 浅白隐球酵母菌保鲜剂 (Cryptococcus albidus antistaling agent ) 是由 王傲雪 吕游 刘佳音 陈秀玲 张瑶 张贺 冯明芳 郭兰 于 2019-10-08 设计创作，主要内容包括：本发明公开了一种浅白隐球酵母菌保鲜剂,所述保鲜剂由浅白隐球酵母菌和抗坏血酸复合而成,其可用于油豆角采后保鲜。贮藏试验表明：相比于对照各处理的腐烂率、锈斑指数及失重率都有所降低,维生素C含量、叶绿素含量和可溶性蛋白含量下降幅度缓慢,对油豆角采后品质有积极的影响。in vitro和in vivo试验说明浅白隐球酵母菌可通过快速繁殖的方式与病原菌竞争营养和空间,竞争作用是酵母菌抑菌机制之一。浅白隐球酵母菌保鲜剂处理的油豆角在贮藏期间,超氧化物歧化酶、苯丙氨酸解氨酶、过氧化氢酶活性在前期均表现为升高,豆荚内的丙二醛含量的升高得到抑制,表明浅白隐球酵母菌对油豆角抗病性有诱导作用。(The invention discloses a cryptococcus albidus preservative which is compounded by cryptococcus albidus and ascorbic acid and can be used for preserving picked oil beans. The storage test shows that: compared with the control, the rotting rate, the rust spot index and the weight loss rate of each treatment are reduced, the vitamin C content, the chlorophyll content and the soluble protein content are reduced slowly, and the quality of the picked oil kidney beans is positively influenced. The in vitro and in vivo tests show that the cryptococcus albidus can compete with pathogenic bacteria for nutrition and space in a rapid propagation mode, and the competition effect is one of yeast bacteriostasis mechanisms. During the storage period of the green beans treated by the cryptococcus albidus preservative, the activities of superoxide dismutase, phenylalanine ammonia lyase and catalase are increased at the early stage, and the increase of the malondialdehyde in the bean pods is inhibited, which indicates that the cryptococcus albidus has an induction effect on the disease resistance of the green beans.)

1. The cryptococcus albidus preservative is characterized by being compounded by cryptococcus albidus and ascorbic acid, wherein the cryptococcus albidus preservative comprises the following components in parts by weight: the concentration of Cryptococcus albidus is 1 × 10²～1×10⁸cfu/mL。

2. The cryptococcus albidus antistaling agent according to claim 1, characterized in that the concentration of the cryptococcus albidus is 1 x 10⁸cfu/mL。

3. The use of the cryptococcus albidus antistaling agent of claim 1 or 2 in the postharvest preservation of the kidney beans.

Technical Field

The invention relates to a yeast preservative.

Background

During the storage and transportation of picked fruits and vegetables, the phenomena of wilting, mildew and decay often occur due to respiratory metabolism activity, microbial action and water loss. The rot caused by the microbial infection is not rare, pathogenic microorganisms invade through necrotic tissues and wounds on the surfaces of fruits and vegetables and propagate by using nutrition and space around an invasion site, so that the fruits and vegetables are infected and rotted, the quality of the fruits and vegetables is reduced, even the commodity value is lost, and the loss is serious.

For a long time, different methods for inhibiting postharvest diseases are gradually applied to the storage and preservation processes of fruits and vegetables, wherein the most common method is a chemical method with low cost and simple and convenient operation, but the method has the defects that the residue of chemical agents threatens human health, causes adverse effects on the environment and causes resistance to postharvest disease pathogenic bacteria after long-term use. The low-temperature storage and other modes also have the problems of large energy consumption, high cost, unstable fruit and vegetable quality and the like. More and more postharvest disease control methods are applied to fruit and vegetable preservation, and aim to make up for the defects of other modes. Along with the development of biotechnology, the mode of controlling postharvest diseases by using a biological means and reducing fruit and vegetable rot gradually appears in the visual field of people, and the development of a novel biological agent for safely and effectively inhibiting postharvest diseases to be applied to fruit and vegetable fresh-keeping has received wide attention.

At present, many biocontrol bacteria and fungi are applied to disease control, wherein the yeast is concerned because of the characteristics of high safety, wide antibacterial spectrum, rapid growth, high genetic stability, low requirement on nutrition, high tolerance to chemical drugs, capability of being used in combination with other methods and the like.

The antagonistic yeast as one of antagonistic bacteria for preventing and treating postharvest diseases of fruits and vegetables has the main advantages of low requirement on environment, strong stress resistance, rapid propagation, no toxin, small influence by chemical substances, wide antibacterial spectrum and obvious antagonistic effect, and can improve the biocontrol effect by composite application, combination with other antibacterial methods or means of genetic engineering. It is found that antagonistic yeast can produce substances for decomposing mycotoxin or reduce accumulation of toxin on fruit, so that the antagonistic yeast becomes a main strain for biological prevention and treatment of postharvest disease research. There are about more than 600 kinds of yeasts reported at present, and dozens of kinds of yeasts having biocontrol ability have been found, and the kinds of these biocontrol yeasts are mainly concentrated on Cryptococcus (Cryptococcus), Candida (Candida), Rhodotorula (Rhodotorula) and Pichia (Pichia).

Disclosure of Invention

The invention provides a cryptococcus albidus preservative by researching the inhibition effect of saccharomycetes on postharvest diseases of snap beans, the preservation effect of saccharomycetes on snap beans and the biocontrol mechanism of postharvest pathogenic bacteria. The invention firstly researches the fresh-keeping effect of the microzyme in the snap beans, has obvious fresh-keeping effect when the cryptococcus albidus and the fresh-keeping auxiliary agent are used together, can reduce the postharvest diseases of the snap beans, and provides a theoretical basis for better applying the yeast-preventing bacteria to postharvest fresh-keeping of horticultural products.

The purpose of the invention is realized by the following technical scheme:

a cryptococcus albidus antistaling agent is compounded by cryptococcus albidus and ascorbic acid, wherein: the concentration of Cryptococcus albidus is 1 × 10²～1×10⁸cfu/mL, preferably at a concentration of 1X 10⁸cfu/mL。

The cryptococcus albidus preservative can be used for preserving picked oil beans.

In the invention, the Cryptococcus albidus is Cryptococcus albidus WY-1 (Ca 64 for short) and is preserved in the China general microbiological culture Collection center of the China Committee for culture Collection of microorganisms with the preservation number of CGMCC No. 1976.

Compared with the prior art, the invention has the following advantages:

1. the storage test shows that: compared with the control, the rotting rate, the rust spot index and the weight loss rate of each treatment are reduced, the vitamin C content, the chlorophyll content and the soluble protein content are reduced slowly, and the quality of the picked oil kidney beans is positively influenced.

2. The in vivo test shows that: the cryptococcus albidus can be well colonized on the surfaces of the pods, and can be rapidly propagated in a short time, and then the flora reaches a stable level. The cryptococcus albidus and the ascorbic acid have an inhibiting effect on the occurrence of gray mold, and the prevention and treatment effect is obvious. The in vitro and in vivo tests show that the cryptococcus albidus can compete with pathogenic bacteria for nutrition and space in a rapid propagation mode, and the competition effect is one of yeast bacteriostasis mechanisms.

3. During the storage period of the oil beans treated by the cryptococcus albidus and ascorbic acid compound dosage form, the activities of superoxide dismutase (SOD), Phenylalanine Ammonia Lyase (PAL) and Catalase (CAT) are all shown to be increased in the early period, and the increase of the content of Malondialdehyde (MDA) in bean pods is inhibited, which indicates that the cryptococcus albidus has an induction effect on the disease resistance of the oil beans.

Drawings

FIG. 1 shows the antagonistic action of Cryptococcus albidus and Botrytis cinerea, wherein A is Cryptococcus albidus and B is a control.

FIG. 2 shows the inhibition rate of Cryptococcus albidus on Botrytis cinerea hyphae.

FIG. 3 shows the growth dynamics of Cryptococcus albidus on the pod surface.

FIG. 4 shows the effect of Cryptococcus albidus antistaling agent on the weight loss rate of the kidney bean.

FIG. 5 shows the effect of Cryptococcus albidus antistaling agent on Vc content of semen Phaseoli Radiati.

FIG. 6 shows the effect of Cryptococcus albidus antistaling agent on chlorophyll content of semen Phaseoli Radiati.

FIG. 7 shows the effect of Cryptococcus albidus antistaling agent on the soluble protein content of the kidney bean.

FIG. 8 shows the change of malondialdehyde content in the processed oil bean using Cryptococcus albidus antistaling agent.

FIG. 9 shows the effect of Cryptococcus albidus antistaling agent on the SOD activity of the kidney beans.

FIG. 10 is a graph of the effect of Cryptococcus albidus preservative on the PAL activity of vigna unguiculata.

FIG. 11 shows the effect of Cryptococcus albidus antistaling agent on CAT activity of vigna radiata.

Detailed Description

The technical solution of the present invention is further described below with reference to the accompanying drawings, but not limited thereto, and any modification or equivalent replacement of the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention shall be covered by the protection scope of the present invention.

The cryptococcus albidus preservative provided by the invention is compounded by cryptococcus albidus and ascorbic acid, wherein:

the biological control effect of the cryptococcus albidus preservative on postharvest diseases of the kidney beans is as follows:

1. preparation of Cryptococcus albidus suspension

Inoculating the Cryptococcus albidus seed liquid into 50mL YPD culture medium (the inoculation amount is 2%), performing shake culture at 28 ℃ and 200r/min for 36h to obtain Cryptococcus albidus fermentation liquid, centrifuging at 5000r/min for 10min, collecting thalli, and blending with sterile physiological saline (0.9%) to obtain Cryptococcus albidus suspension with the concentration required by the test for later use.

2. Isolation of pathogenic bacteria and preparation of bacterial suspension

The method comprises the steps of transferring and purifying botrytis cinerea separated from naturally-occurring green beans for multiple times, culturing for 10 days at 26 ℃, adding 2mL of sterile water into a culture dish, gently scraping cultured spores and thalli by using a sterile blade, washing the thalli by using sterile water, fully vibrating, filtering hyphae by using four layers of gauze to obtain a pathogenic spore suspension, and then blending to the concentration required by the test.

3. Antagonistic test against pathogenic bacteria

(1) A filter paper sheet method: placing Botrytis cinerea fungus cake with diameter of 5mm on one side of PDA plate at equal distance from midpoint, placing filter paper sheet with diameter of 1mm on one side, and dripping 15 μ L of 110⁸The light cryptococcus albidus suspension. Culturing at 25 deg.C for 7d, observing growth of Botrytis cinerea with plate inoculated with Botrytis cinerea and sterile water as control, and repeating treatment for 3 times.

(2) Coating method: taking 100 μ L of 1 × 10⁸The method comprises the following steps of inoculating cfu/mL of shallow cryptococcus albidus suspension on a PDA solid culture medium, uniformly coating the PDA solid culture medium with a coating rod, inoculating a circular Botrytis cinerea cake with the diameter of 5mm on the culture medium after air drying, performing static culture at 25 ℃ for 7d, observing the growth condition of the Botrytis cinerea by taking the PDA solid culture medium coated with sterile water and inoculated with the Botrytis cinerea as a control, and repeating the treatment for 3 times in each group.

4. Inhibition of shallow cryptococcus albidus suspension on pathogenic bacteria hyphae

Inoculating a botrytis cinerea cake with the diameter of 5mm into a 50mLPDB culture medium, respectively inoculating the cryptococcus albidus suspension with the inoculation amount of 2% (V: V), shaking the flask at 25 ℃ for 7d at 200r/min, taking the non-inoculated yeast as a control, recording the growth condition of botrytis cinerea hyphae, filtering the obtained hyphae with gauze, drying and weighing, and determining the inhibition degree of the cryptococcus albidus on the growth of the botrytis cinerea hyphae, wherein each treatment is repeated for 3 times.

Prevention and treatment effect of cryptococcus albidus on green bean diseases

Selecting semen Phaseoli Radiati with consistent color and no mechanical injury or disease, cutting 5mm (width) and 12mm (depth) wound with aseptic blade at equal distance on bean pod, and treating with Cryptococcus albidus antistaling agent with yeast concentration of 1 × 10⁸cfu/mL。

Naturally drying the processed green beans, and inoculating spore with concentration of 1 × 10 after 12h⁶cfu/mL of Botrytis cinerea, bagging the Botrytis cinerea, keeping the humidity at 90%, storing the Botrytis cinerea at room temperature, recording and observing the incidence of the pods from the next day, and counting every three days. The experiment was repeated three times.

The disease stage of the kidney bean: grade 0, no disease occurs in the fruit;

grade 1, the disease area is less than 10% of the fruit area;

grade 2, the disease area accounts for 10 to 30 percent of the fruit area;

grade 3, the area of attack is more than 30% of the area of the fruit.

Disease index is 100 × Σ (number of fruits affected at each stage × corresponding stage number)/(total number of surveys × highest number of disease stages)

The prevention and treatment effect is (contrast disease index-treatment disease index)/contrast disease index multiplied by 100 percent

Growth dynamics of Cryptococcus albidus on surface of semen Phaseoli vulgaris

Treating semen Phaseoli Radiati with 2% sodium hypochlorite solution for 3min, washing with sterile water, and air drying. By 1X 10⁸Uniformly spraying cfu/mL of light cryptococcus albidus suspension on the surfaces of the bean pods, taking out the bean pods, airing the bean pods, bagging the bean pods to keep a certain relative humidity, storing the bean pods at room temperature, taking the number of yeast strains measured after 1 hour of inoculation as an initial value (0 hour), measuring the number of the yeast strains once every 12 hours, and measuring the dynamic bacteria quantity within 96 hours. The method for measuring the number of yeasts on the surfaces of the pods comprises the following steps: soaking the processed green beans in 500mL of sterile water, ultrasonically cleaning for 5min, and then measuring the number of the Cryptococcus albidus in the cleaning solution by a coating method and microscopic examination. The experiment was repeated 3 times.

Storage test of extracted green beans

Selecting the oil kidney beans with consistent sizes and no diseases or mechanical damages, and treating the oil kidney beans after purchase for postharvest fruit storage tests. Mixing semen Phaseoli Radiati with 1 × 10⁸Uniformly spraying the cfu/mL cryptococcus albidus preservative on the surfaces of the bean pods, taking out the bean pods, naturally airing the bean pods, keeping 90% of relative humidity by using a preservative film and bagging mode, and storing the bean pods at room temperature. The rotting condition of the green beans in different treatment groups is observed every 3d by taking untreated green beans as a control group and 12d as a storage period, various quality indexes of fruits are measured (referring to physiological and biochemical experiment guidance after fruit and vegetable harvest and slightly changing), and the experiment is repeated for 3 times.

1. And (4) adopting a weighing method to determine. The weight loss of the kidney beans was measured from the beginning of storage, and every 3 days.

Weight loss rate (fruit original weight-weight at the time of measurement)/original weight × 100%.

2. Rate of decay

Dividing the rotten area size of the fruit into 4 grades:

grade 0, no rot;

grade 1, the rotten area is less than 20% of the fruit area;

grade 2, the rotten area accounts for 20 to 50 percent of the area of the fruits;

grade 3, the rotten area is 50-70% larger than the area of the fruit.

The decay index was calculated by the following formula:

the rotting rate is ∑ (rotting grade x number of pods of that grade)/(highest rotting grade x number of total pods) × 100%

3. The rust spot index is divided into 0-3 grades according to the occurrence degree of rust spots on the surfaces of the green beans:

grade 0-no rust;

grade 1-less rust, having commercial value;

grade 2-more rust spots, no commercial value;

grade 3-severe rust spots, loss of eating quality.

Rust index ═ Σ (rust grade × number of grades)/(highest grade × total number of samples) × 100

4. Chlorophyll content

Weighing 0.5g of sample, shearing, adding 1mL of distilled water, adding a small amount of calcium carbonate, grinding, adding 10mL of an extracting solution consisting of absolute ethyl alcohol and acetone in a ratio of 1:2(V: V), leaching for 3h in a dark place until the residue turns white, and operating according to the kit instructions.

5. Ascorbic acid content

A proper amount of the kidney bean sample is weighed, a small amount of 1% oxalic acid is respectively added to the kidney bean sample, the kidney bean sample is ground into slurry by a mortar, gauze is used for filtering, the filtrate is transferred to a 50mL volumetric flask, and then 2% oxalic acid is used for metering the volume. 1.0mL of standard ascorbic acid solution (0.1mg/mL) was added to 9.0mL of oxalic acid solution (1% concentration), and the mixture was titrated with 0.1% of 2, 6-dichlorophenol indophenol by a microtitre tube to be reddish, and the end point was reached after no discoloration within 15 seconds. The value of T (mean) was calculated from the volume of dye used, i.e.1 mL of dye corresponds to how many mg of Vc. Exactly 10.0mL of the prepared sample filtrate were pipetted in duplicate into two 50mL Erlenmeyer flasks, as before.

Resist to damageContent of ascorbic acid: m is VT/m₀×100

In the formula, m: the mass (mg) of Vc contained in 100g of sample;

v: volume of dye used for titration (mL);

t: mass Vc (mg/mL) can be oxidized by dye per milliliter;

m₀: 10mL of the sample solution contained the mass number (g) of the sample.

6. Soluble proteins

Sample 0.5g was weighed, and the weight (g): grinding with 1:9 (mL) physiological saline, homogenizing in ice water bath, centrifuging at 2500r/min for 10min, collecting supernatant, diluting with 1:4 physiological saline, and determining according to kit instructions.

7. Malondialdehyde content

Sample 0.5g was weighed, and the weight (g): normal saline is added into the mixture with the volume (mL) of 1:9, a 10% tissue homogenate is prepared in an ice water bath, and the MDA content is measured by adopting a kit.

8. Superoxide dismutase (SOD) Activity

According to the weight (g): adding physiological saline solution in a volume (mL) of 1:4 to prepare 20% tissue homogenate, centrifuging at 3500r/min for 10min, and taking supernatant to measure according to the kit instructions.

9. Catalase (CAT) Activity

Weighing a kidney bean sample by 0.5g, adding physiological saline, and weighing (g): volume (mL) ═ 1:9, ice water bath prepared 10% homogenate, 2500r/min centrifuged 10min, supernatant was taken, and 1: and 4, adding physiological saline for dilution, and operating according to the kit instructions.

10. Phenylalanine Ammonia Lyase (PAL)

According to the weight (g): adding the extractive solution at volume (mL): 1:9, homogenizing in ice water bath, 10000r/min, centrifuging for 10min, and performing according to kit instructions.

Fifth, result and analysis

1. Biological control effect of cryptococcus albidus on postharvest diseases of oil beans

(1) Confrontation test

The results of the plate confrontation test filter paper method show that the cryptococcus albidus does not have obvious inhibition zone on botrytis cinerea, but compared with the control, the growth of botrytis cinerea hyphae does not cover the filter paper, which shows that the inhibition mechanism of the cryptococcus albidus does not directly produce strong and effective bactericidal substances to inhibit pathogenic bacteria. In the coating method inhibition test, the growth of botrytis cinerea is obviously inhibited when the plate inoculated with the shallow cryptococcus albidus is coated, only a very small amount of hyphae can be seen, but the shallow cryptococcus albidus grows well, which indicates that the shallow cryptococcus albidus can effectively utilize nutrition and space for propagation. The results of the plate-aligning of the filter paper sheet method and the coating method are shown in FIG. 1.

(2) Influence of Cryptococcus albidus on growth of pathogenic bacteria hyphae after oil bean picking

After the cryptococcus albidus and the botrytis cinerea are subjected to symbiotic culture at 25 ℃ for seven days, the hypha inhibition effect is shown in figure 2. After hyphae are dried and weighed, the inhibition rate of the cryptococcus albidus on the botrytis cinerea hyphae is found to reach 94.74%.

(3) Control effect of different treatments on fruit with postharvest disease of green beans

The cryptococcus albidus inhibits the growth of pathogenic bacteria on bean pods, the disease index is 24.77, and the prevention and treatment effect reaches 65.66%. The cryptococcus albidus has good adhesion capacity on the surface of the fruits, and the propagation speed of the cryptococcus albidus is higher than that of pathogenic bacteria, so that the cryptococcus albidus can occupy nutrition and propagation space on the surfaces of the fruits in advance, and a dry mycoderm is formed on the wounds of the fruits to limit the growth and propagation of the pathogenic bacteria.

(4) Growth dynamics of Cryptococcus albidus on pods

FIG. 3 shows the dynamic change of Cryptococcus albidus colonies on pods, and the results show that Cryptococcus albidus can colonize on the surface of the green beans and has an increasing process, the maximum value is reached in 36-48 h, the bacterial quantity is slightly reduced after 48h, but the colony number is stable within the investigation time.

2. Storage test of post-harvest oil beans

(1) Influence on storage quality of green beans

a. Effect on rotting and rusty spots during storage of green beans

The cryptococcus albidus + ascorbic acid-treated kidney beans were reduced in rot and rust compared to the controls, with a rot rate and rust index of 25.35% and 20.44%, respectively, significantly lower than the controls (P <0.05), 49.58% and 54.12%, respectively, for the cryptococcus albidus + ascorbic acid-treated kidney beans.

b. Influence on Water content during storage of the beans

The transpiration and respiration of the fruit during storage cause a large amount of water loss, which is a factor of weight reduction during storage of the beans. As can be seen from FIG. 4, the weight loss rate of Cryptococcus albidus + ascorbic acid treatment was 6.04% at 6 days of storage, which is 53.8% of the control. When the edible oil is stored for the 9 th day, the weight loss ratio of the cryptococcus albidus and the ascorbic acid is 16.9 percent, which is 66 percent of the comparison, and the weight loss ratio is obviously lower than the comparison (P is less than 0.05), and the water loss of the oil kidney beans can be reduced.

c. Influence on vitamin C content of green beans

As can be seen from FIG. 5, the content of vitamin C in Cryptococcus albidus + ascorbic acid gradually decreased with the number of days of storage. The vitamin C content of the oil beans in the first three days of storage is reduced to some extent, but the difference between the oil beans and the control is small, the vitamin content of the control treatment from 3d to 6d is reduced quickly, and the loss of the vitamin C of the oil beans in the storage period is delayed. The results after 9 days storage showed that the vitamin C content was significantly different from the control.

d. Influence on chlorophyll content of green beans

Changes in chlorophyll content during storage of the green beans are shown in fig. 6, showing a tendency to decrease throughout the storage period, and the rate of decrease increases from 3d after storage. The reduction rate of the chlorophyll content of the cryptococcus albidus and the ascorbic acid treated in 3-6 days is smaller than that of the control, which indicates that the cryptococcus albidus and the ascorbic acid can relieve pod yellowing in different degrees, wherein the cryptococcus albidus and the ascorbic acid are reduced by 30.5% compared with the initial content, keep a higher level during storage, and have a significant difference (p is less than 0.05) with the control.

e. Influence on soluble protein content of vigna unguiculata

FIG. 7 shows the change in soluble protein content of Cryptococcus albidus + ascorbic acid-treated locust beans during storage. The content of soluble protein is slightly reduced in the early storage period, and the content is rapidly increased in the middle storage period along with the extension of the storage time and is rapidly reduced in the final storage period. The reduction in storage 9d was 21.8%. The increase of the content of the soluble protein in the storage process is probably related to the change of the content of the defensive enzyme in the storage process, and the content of the soluble protein at the end stage of the storage is rapidly reduced because the rapid reduction of the soluble protein is related to the degradation of each defensive enzyme along with the aging of fruit tissues, indicates that the quality of the kidney beans is qualitatively changed, and the storage value is gradually lost.

(2) Effect on MDA content during storage of Glycine max

MDA is the product of cellular membranization or lipidization. When plants are stressed or in the process of aging, the generation and elimination mechanism of free radicals in vivo is damaged, and the generation of the free radicals can damage cell membranes, so that the cell membranes are gradually degraded into MDA, and the content of the MDA can reflect the aging degree of the plants. FIG. 8 shows the change of MDA content of Cryptococcus albidus antistaling agent in storage period, the change of MDA content in storage period is not big, and the MDA content is lower than the control in 9d storage.

(3) Effect on SOD Activity during storage of Glycine max

As can be seen from FIG. 9, the SOD enzyme activity tended to increase and then decrease with the increase of the storage time. The SOD enzyme activity of the cryptococcus albidus treated by the cryptococcus albidus and the ascorbic acid is improved in the early storage period, and the SOD enzyme activity of the cryptococcus albidus treated by the cryptococcus albidus and the ascorbic acid is higher than that of a control at the 6 th day of storage, which shows that the SOD enzyme activity of the cryptococcus albidus treated by the cryptococcus albidus and the ascorbic acid has a certain promotion effect in the storage period. The SOD activity of the control group, which was slightly increased at the end of storage, was correlated with infection by pathogenic bacteria at the end of storage.

(4) Effect on PAL Activity during storage of Glycine max

FIG. 10 shows the effect of Cryptococcus albidus preservative on the PAL activity of the storage period of the beans. As can be seen from the figure, the PAL activity of the oil bean is increased by the Cryptococcus albidus + ascorbic acid treatment in the early storage period, which is mainly related to the fruit resistance induced by the Cryptococcus albidus. The cryptococcus albidus + ascorbic acid treatment still maintained higher PAL activity at the end of storage, which is significantly different from the control (P < 0.05).

(5) Effect on CAT Activity during storage of Glycine max

Cryptococcus albidus + ascorbic acid treatment during storage had an effect on the CAT activity of the green beans. CAT activity continuously rises 6 days before storage, and reaches a peak value on the 6 th day, while a peak value on the 9 th day is reached by a contrast, which shows that the CAT activity of the green beans can be promoted by the cryptococcus albidus and the ascorbic acid in the early storage period to different degrees.