Application of 1-octen-3-ol in detecting potato dry rot

Abstract

The present invention provides an application of 1-octen-3-ol in detecting potato dry rot. The 1-octen-3-ol compound of the present invention monitors potato tuber tissues in different disease processes, and based on the detected volatile component 1-octen-3-ol, can effectively distinguish healthy potato samples and potato samples with different degrees of corruption, so the compound can be used to identify potato tubers infected by three-line Fusarium F.tricinctum. The results of the present invention will effectively identify the specific volatile components of dry rot potatoes, and provide a theoretical basis for the diagnosis and identification of potato dry rot based on odor sensing information.

Description

Technical Field

[0001] The invention relates to application of 1-octen-3-ol in detecting potato dry rot. Background Art

[0002] Potatoes are the fourth largest food crop in the world. They can be eaten as a staple food and are also an important source of high-quality starch. They are vigorous, have high yields, and are widely planted. They are an important source of carbohydrates in the diet. During storage, potatoes are extremely susceptible to infection by Fusarium, which causes dry rot, causing tubers to dehydrate and shrink, and cavities to appear inside, causing serious economic losses. It has become an important disease during tuber storage. As the infection time increases, the skin and internal tissues of potatoes have changed to varying degrees, and produce an odor different from that of normal potatoes. In recent years, odor signals have been used as "odor fingerprint markers" to monitor whether fruits and vegetables have rotted during post-harvest storage. It is crucial for the early diagnosis and prevention of potato dry rot.

[0003] At present, the methods used to analyze volatile compounds include gas chromatography-mass spectrometry (GC-MS) and gas phase ion mobility spectrometry (GC-IMS). This technology has the characteristics of high sensitivity, accurate qualitative analysis, and simple sample preparation. At present, this method has been widely used in the detection of flavor substances in foods such as wine, fruits and vegetables, and meat, and has also been used in the identification of Chinese herbal medicine varieties and components. However, there are no reports on the use of solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) technology to analyze the specific volatile substances in potato dry rot tubers. Summary of the invention

[0004] In order to solve the problems existing in the prior art, the present invention provides the use of 1-octen-3-ol in detecting potato dry rot.

[0005] 1-Octen-3-ol is also known as mushroom alcohol; Vinylpentylcarbinol; 1-vinylhexano, molecular formula C8H 16O, with the structural formula of CH2=CHCH(OH)CH2CH2CH2CH2CH3, CAS number: 3391-86-4, is an aliphatic unsaturated alcohol, with the appearance of a colorless to light yellow oily liquid, with the aroma of mushrooms, lavender, roses and hay. In nature, it is mainly found in mint, thyme and fresh mushrooms, and is a natural equivalent spice. It is also contained in trace amounts in many foods such as bananas and berries, beer, pork, river shrimp, soybeans, etc. It is insoluble in water, but soluble in organic solvents such as ethanol. 1-Octene-3-ol is prepared industrially by synthesis rather than separation from natural products. Its main uses are in the preparation of fragrances and pharmaceutical raw materials. However, the inventors of this application unexpectedly discovered that 1-Octene-3-ol detected from potato dry rot tubers can be used to detect whether dry rot occurs in potatoes during postharvest storage.

[0006] The chemical structure of 1-octen-3-ol is as follows:

[0007]

[0008] The present invention selects potato tubers infected by pathogens for 0d, 7d and 14d as test materials, adopts SPME-GC-MS technology to detect volatile components of dry rot potatoes with different disease degrees, and performs statistical analysis in combination with principal component analysis and cluster heat map. On this basis, by analyzing the volatile substances of potato tubers with different infection degrees, a specific volatile compound produced by potato dry rot tubers, 1-octen-3-ol, is identified, providing theoretical support for potato dry rot disease diagnosis based on odor fingerprint information.

[0009] The first object of the present invention is to provide the use of 1-octen-3-ol in detecting potato dry rot.

[0010] Preferably, the potato dry rot is caused by Fusarium thunbergii.

[0011] Preferably, when the relative percentage content of 1-octen-3-ol in the volatile components of potatoes is ≥5%, it is determined that the potatoes have dry rot; preferably, when the relative percentage content of 1-octen-3-ol in the volatile components of potatoes is ≥6.5%, it is determined that the potatoes have dry rot.

[0012] The second object of the present invention is to provide a method for detecting dry rot of potato, which detects the content of 1-octen-3-ol in the potato to be tested, and when the relative percentage content of 1-octen-3-ol in the volatile components of the potato is ≥5%, it is determined that the potato has dry rot; preferably, when the relative percentage content of 1-octen-3-ol in the volatile components of the potato is ≥6.5%, it is determined that the potato has dry rot.

[0013] Preferably, the potato dry rot is caused by Fusarium thunbergii.

[0014] Preferably, the solid phase microextraction-gas chromatography-mass spectrometry method is used to detect the content of 1-octen-3-ol in the potato to be tested.

[0015] Preferably, the solid phase microextraction method is: transferring the potato sample to be tested into an extraction bottle, quickly sealing it, placing the extraction bottle into a solid phase microextractor for preheating; inserting the solid phase microextraction head into the top cavity of the extraction bottle to perform headspace extraction.

[0016] Preferably, the detection conditions of the gas chromatography are:

[0017] The chromatographic column is DB-WAX (30.0m×250μm, 0.25μm); the initial temperature is 40℃ and maintained for 3min, then increased to 200℃ at a rate of 5℃ / min, and then increased to 240℃ at a rate of 10℃ / min and maintained for 5min; the vaporization chamber temperature is 250℃; the transfer line temperature is 240℃; the carrier gas is He; the carrier gas flow rate is 1.0mL / min; no splitting.

[0018] Preferably, the detection conditions of the mass spectrometer are: EI source; electron energy 70eV; ion source temperature 230°C; quadrupole 150°C; scanning mode is Scan; and the scanning mass range is 20 to 500u.

[0019] The beneficial effects of the present invention are as follows:

[0020] In production practice, it is generally necessary to cut open potato tubers to determine whether a disease has occurred. For large potato storage warehouses, this method can easily cause waste of raw materials. However, the present invention does not require the destruction of tubers, but only requires the detection of changes in the content of volatile organic compounds (1-octen-3-ol) generated during storage to determine whether dry rot has occurred in potatoes, thereby greatly improving the detection efficiency and making the detection results more accurate.

[0021] The volatile compound (1-octen-3-ol) for monitoring potato dry rot caused by infection of Fusarium thunbergii provided by the present invention is produced by the fungus during the interaction with potato tubers and can be used to monitor whether dry rot occurs in potato tubers during post-harvest storage.

[0022] The 1-octen-3-ol compound of the present invention monitors potato tuber tissues in different disease processes, and based on the detected volatile component 1-octen-3-ol, can effectively distinguish healthy potato samples and potato samples with different degrees of corruption, so the compound can be used to identify potato tubers infected by F. tricinctum. The results of the present invention will effectively identify the specific volatile components of dry rot potatoes, and provide a theoretical basis for the diagnosis and identification of potato dry rot based on odor sensing information. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0024] Figure 1 This is a bar graph showing the changes in the content of 1-octen-3-ol in potato tubers after being infected by F.tricinctum.

[0025] Figure 2 The gas chromatography-mass spectra of 1-octen-3-ol when potato tubers were infected with F.tricinctum at different times.

[0026] Among them, Figure A shows the infection at 0 days, Figure B shows the infection at 7 days, and Figure C shows the infection at 14 days. DETAILED DESCRIPTION

[0027] The following examples are provided to facilitate a better understanding of the present invention, but are not intended to limit the present invention. The experimental methods in the following examples are conventional methods unless otherwise specified. The experimental materials used in the following examples are purchased from conventional biochemical reagent companies unless otherwise specified.

[0028] Example 1

[0029] 1. Potato preparation

[0030] The Longshu '10' miniature potato of the present invention was obtained from the virus-free seedling shed in Huichuan Town, Dingxi City, Gansu Province, China in October 2023. The harvested potato tubers were individually packaged in foam plastic clean bags at physiological maturity, and transported to the laboratory on the day of harvest. The potato tubers with uniform size, no obvious visible defects and rot were screened, totaling 180. All potato tubers were surface disinfected, first soaked in 0.2% sodium hypochlorite solution for 2 minutes, then rinsed with distilled water and naturally air-dried at room temperature. After drying, the miniature potato tubers were randomly divided into two groups, each with 90, which were used as the simulated inoculation group (W-control) of sterile water and the experimental group (F.tricinctum) of Fusarium.

[0031] 2 Pathogen and spore suspension

[0032] The strain of F. tricinctum was obtained from the Postharvest Laboratory of the School of Food Science and Engineering, Gansu Agricultural University. The preparation of the spore suspension was based on the method of Tahir et al. The conidia of the pathogen were obtained from PDA medium cultured at 25°C for 7 days. The culture was soaked in sterile water containing 0.05% Tween-80 by volume, gently rubbed with a glass rod, and then filtered through two layers of sterile cheesecloth, and the concentration of conidia was adjusted to 1×10 using a hemocytometer. 6 CFU·mL -1 .

[0033] 3. Fruit inoculation

[0034] A 1 mm wide and 2 mm deep hole was punched around the equator of each surface-sterilized potato using a sterile punch pin and inoculated with 20 μL of 1 × 10 6 CFU·mL -1 The three-line Fusarium F.tricinctum spore suspension was used as the experimental group (marked as F.tricinctum in the bar graph), while the potatoes inoculated with 20μL sterile water after artificial injury were used as the control group for simulated inoculation (marked as W-control in the bar graph). After natural drying, 10 tubers were randomly selected from each treatment group and placed in a perforated fresh-keeping bag. Each treatment group was divided into 9 bags in total and placed in the same polyethylene fresh-keeping box (40cm×30cm×15cm), a total of two fresh-keeping boxes, packed with black polyethylene plastic bags and stored in an environment of 20±1℃, and maintained at a relative humidity of 85-90%. Tubers were sampled and evaluated at three time points: 0, 7 and 14d after inoculation.

[0035] The sampling method is as follows: sampling is carried out at each detection time point, 3 bags of samples are randomly taken out from each treatment group as 3 biological replicates for each treatment, and samples are taken from the damaged inoculation site of 10 tubers in each group, and the diseased tissue and potato flesh tissue at the junction of diseased and healthy tissue (only potato flesh tissue is collected) are taken from the circumference of the damaged inoculation site at a radius of about 2mm×2mm from the damaged inoculation site. 3.0g of samples are collected from each group for the determination of volatile compounds.

[0036] 4 Analysis of volatile compounds

[0037] 4.1 Determination of volatile compounds. Weigh 3.0g of sample and transfer it into a 15mL extraction bottle, then quickly seal it. Aging the SPME extraction fiber head at 250℃ in the GC-MS injection port until there are no impurity peaks. Place the extraction bottle on the solid phase microextraction device and set the temperature to 80℃; preheat the extraction bottle in the extraction device for 15min; insert the SPME extraction head into the headspace of the sample through the bottle cap, push out the fiber head, the extraction head is about 1.0cm above the upper surface of the sample, and the headspace extraction is 40min; withdraw the fiber head and pull the extraction head out of the extraction bottle; then insert the extraction head into the GC-MS injection port, push out the fiber head, analyze at 250℃ for 3min, and inject and analyze.

[0038] The detection conditions of gas chromatography are:

[0039] The chromatographic column was DB-WAX (30.0m×250μm, 0.25μm); the initial temperature was 40℃ and maintained for 3min, then increased to 200℃ at a rate of 5℃ / min, and increased to 240℃ at a rate of 10℃ / min and maintained for 5min; the vaporization chamber temperature was 250℃; the transfer line temperature was 240℃; the carrier gas was He; the carrier gas flow rate was 1.0mL / min; no splitting.

[0040] The detection conditions of mass spectrometry are: EI source; electron energy 70 eV; ion source temperature 230°C; quadrupole 150°C; scanning mode is Scan; scanning mass range is 20 to 500u.

[0041] 4.2 Qualitative analysis: The detected compounds were qualitatively analyzed using the NIST11 mass spectrometry database. When screening the database, interfering peaks must be eliminated.

[0042] 4.3 Quantitative analysis: The peak area normalization method was used for relative quantification. The formula is:

[0043]

[0044] Where: C i ——Content of a certain identified component, %;

[0045] A i ——Peak area of ​​a certain identified component;

[0046] n——indicates the total number of identified components.

[0047] The quantitative analysis results are shown in Table 1 and Figure 1 , Figure 2 From Table 1 and Figure 1 , Figure 2It can be seen that at different stages of infection with Fusarium thaliana, the relative content of the characteristic volatile compound 1-octen-3-ol in potato tubers gradually increased with the extension of infection time. After 7 days of infection, the relative percentage of 1-octen-3-ol was 6.7307%; after 14 days of infection, the relative percentage of 1-octen-3-ol reached 41.5341%, showing a statistically significant difference. In the control group, the relative percentage of 1-octen-3-ol in potato volatile components remained almost unchanged at different times.

[0048] Therefore, it can be inferred that when the relative percentage of 1-octen-3-ol in the volatile components of potatoes is ≥5%, it can be determined that dry rot has occurred in potatoes.

[0049] Figure 1 This is a bar graph showing the changes in the content of 1-octen-3-ol in potato tubers after being infected by F.tricinctum.

[0050] Figure 2 The gas chromatography-mass spectra of 1-octen-3-ol when potato tubers were infected with F.tricinctum at different times.

[0051] Among them, Figure A shows the infection at 0 days, Figure B shows the infection at 7 days, and Figure C shows the infection at 14 days.

[0052] Table 1 Relative percentage content of all volatile compounds detected in potato dry rot tubers by the present invention

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. Application of 1-octen-3-ol in detecting potato dry rot; the potato dry rot is caused by Fusarium thunbergii.

2. The use according to claim 1, characterized in that: When the relative percentage of 1-octen-3-ol in the volatile components of potatoes is ≥5%, it is determined that the potatoes have dry rot.

3. The use according to claim 2, characterized in that: When the relative percentage of 1-octen-3-ol in the volatile components of potatoes is ≥6.5%, it is determined that the potatoes have dry rot.

4. A method for detecting potato dry rot, characterized in that: The content of 1-octen-3-ol in the tested potato is detected. When the relative percentage content of 1-octen-3-ol in the volatile components of the potato is ≥5%, it is determined that the potato has dry rot; the dry rot is caused by Fusarium trilineatum.

5. The method according to claim 4, characterized in that: When the relative percentage of 1-octen-3-ol in the volatile components of potatoes is ≥6.5%, it is determined that the potatoes have dry rot.

6. The method according to claim 4 or 5, characterized in that: Solid phase microextraction-gas chromatography-mass spectrometry was used to detect the content of 1-octen-3-ol in the potatoes.

7. The method according to claim 6, characterized in that: The solid phase microextraction method is as follows: a potato sample to be tested is transferred into an extraction bottle, which is quickly sealed, and the extraction bottle is placed in a solid phase microextractor for preheating; a solid phase microextraction head is inserted into the top cavity of the extraction bottle to perform headspace extraction.

8. The method according to claim 6, characterized in that: The detection conditions of the gas chromatography are: The chromatographic column was DB-WAX; the initial temperature was 40 °C and maintained for 3 min, then increased to 200 °C at a rate of 5 °C / min, and then increased to 240 °C at a rate of 10 °C / min and maintained for 5 min; the vaporization chamber temperature was 250 °C; the transfer line temperature was 240 °C; the carrier gas was He; Carrier gas flow rate: 1.0 mL / min; no splitting.

9. The method according to claim 6, characterized in that: The detection conditions of the mass spectrometer are: EI source; electron energy 70 eV; ion source temperature 230°C; quadrupole 150°C; scanning mode is Scan; scanning mass range is 20-500u.

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