A sesame oil fingerprint construction method, sesame oil fingerprint and sesame oil quality control method

Abstract

This application relates to the field of analytical detection technology, specifically disclosing a method for constructing a fingerprint spectrum of sesame oil, a fingerprint spectrum of sesame oil, and a method for quality control of sesame oil. The method for constructing a fingerprint spectrum of sesame oil provided in this application includes the following steps: (1) preparing a reference solution and a test solution; (2) injecting the reference solution and the test solution into a liquid chromatograph, and performing high-performance liquid chromatography separation and detection using a mobile phase gradient elution method; the mobile phase gradient elution program is as follows: during 0-50 min, dichloromethane 20%, acetonitrile 80%; during 50-51 min, dichloromethane 60%, acetonitrile 40%; during 51-65 min, dichloromethane 20%, acetonitrile 80%; the flow rate of the mobile phase is 0.8-1.2 mL / min. The method for constructing a fingerprint spectrum of sesame oil in this application can scientifically, accurately, and comprehensively evaluate the quality of sesame oil from different producing areas, and is of great significance for the quality control and adulteration identification of sesame oil.

Description

Technical Field

[0001] This application relates to the field of analytical testing technology, specifically to a method for constructing a fingerprint spectrum of sesame oil, a fingerprint spectrum of sesame oil, and a method for quality control of sesame oil. Background Technology

[0002] Sesame oil is a fatty oil obtained by pressing and refining the mature seeds of Sesamum indicum L., a plant in the family Sesamumceae. Sesame oil is a clear, pale yellow or brownish-yellow liquid with a faint odor or a aroma reminiscent of roasted sesame seeds, and a mild taste. Current research indicates that the main components of sesame oil include sesamol, sesamin, sesaminol, triglycerides, etc., and it is also rich in various amino acids and minerals. Therefore, it is widely used in food, traditional Chinese medicine, and health products.

[0003] Currently, there is limited literature on the quality evaluation of sesame oil, and existing methods are insufficient to comprehensively assess the quality of sesame oil from different origins. While the 2020 edition of the Chinese Pharmacopoeia specifies the content of sesame oil, it does not address the fingerprinting of sesame oil. Furthermore, the current method is complex to prepare and consumes significant energy, making it unsuitable for widespread use.

[0004] Therefore, it is necessary to establish a scientific, accurate, and comprehensive method to evaluate the quality of sesame oil from different producing areas in order to achieve quality control and adulteration identification of sesame oil. Summary of the Invention

[0005] In order to scientifically, accurately and comprehensively evaluate the quality of sesame oil, this application provides a method for constructing a fingerprint spectrum of sesame oil, a fingerprint spectrum of sesame oil, and a method for quality control of sesame oil.

[0006] Firstly, the method for constructing the sesame oil fingerprint spectrum provided in this application adopts the following technical solution:

[0007] A method for constructing a sesame oil fingerprint spectrum includes the following steps:

[0008] (1) Prepare reference solution and test solution;

[0009] (2) The reference solution and the test solution were injected into a liquid chromatograph, and high performance liquid chromatography separation and detection were performed using an octadecylsilane-bonded silica gel column, a mobile phase gradient elution method and an evaporative light detector to obtain a fingerprint spectrum. The mobile phase gradient elution program was as follows: 20% dichloromethane and 80% acetonitrile during the period from 0 to 50 min; 60% dichloromethane and 40% acetonitrile during the period from 50 to 51 min; and 20% dichloromethane and 80% acetonitrile during the period from 51 to 65 min. The flow rate of the mobile phase was 0.8-1.2 mL / min.

[0010] This application provides a method for constructing a fingerprint spectrum of sesame oil. By detecting the fingerprint spectrum of the sample to be tested, the sequential order and interrelationship of fingerprint characteristic peaks are obtained. By comparing it with a standard fingerprint spectrum, the similarity between the sesame oil sample and the reference standard is obtained, thereby monitoring the quality of sesame oil and achieving authenticity identification. The method provided in this application can effectively avoid the one-sidedness of judging the overall quality of sesame oil based on the determination of individual chemical components. It has the advantages of simple operation, high detection accuracy and precision, and good reproducibility.

[0011] In some embodiments, the flow rate of the mobile phase can be 0.8-1.0 mL / min or 1.0-1.2 mL / min.

[0012] In one specific implementation, the flow rate of the mobile phase may also be 0.8 mL / min, 1.0 mL / min, or 1.2 mL / min.

[0013] Optionally, in the high-performance liquid chromatography separation and detection, the drift tube temperature is 75-85℃, the column temperature is 25-35℃, and the injection volume is 4.5-5.5μL.

[0014] In some implementations, the column temperature can be 25-30°C or 30-35°C.

[0015] In one specific implementation, the column temperature may also be 25°C, 30°C, or 35°C.

[0016] Optionally, the test solution is prepared by extracting the sesame oil sample using an organic solvent, wherein the organic solvent is acetone, a mixture of acetone and dichloromethane, or a mixture of acetone and trichloromethane.

[0017] Optionally, the organic solvent is acetone and dichloromethane in a volume ratio of 1:1.

[0018] Optionally, the extraction method is selected from ultrasound, vibration and reflux; the extraction time is 10-20 min.

[0019] Optionally, the extraction method is ultrasound, wherein the power of the ultrasound is 400-600W and the frequency is 35-45kHz. In a specific embodiment, the power of the ultrasound is 500W, the frequency is 40kHz, and the duration is 10min.

[0020] Optionally, the reference standard is 1,2-dioleoyl-3-linoleic acid glyceride; the concentration of 1,2-dioleoyl-3-linoleic acid glyceride in the reference standard solution is 0.1-0.2 mg / mL.

[0021] Secondly, this application provides a sesame oil fingerprint spectrum.

[0022] A sesame oil fingerprint spectrum is obtained using the aforementioned method for constructing sesame oil fingerprint spectra. The sesame oil fingerprint spectrum contains 14 characteristic peaks, with peak number 4 as the reference peak. The relative retention time of each peak is within ±10% of a specified value. The specified values ​​for each peak are as follows:

[0023] Peak 1: Relative retention time 0.8237; Peak 2: Relative retention time 0.92; Peak 3: Relative retention time 0.943; Peak 4: Relative retention time 1.000; Peak 5: Relative retention time 1.013; Peak 6: Relative retention time 1.023; Peak 7: Relative retention time 1.047; Peak 8: Relative retention time 1.077; Peak 9: Relative retention time 1.09; Peak 10: Relative retention time 1.102; Peak 11: Relative retention time 1.113; Peak 12: Relative retention time 1.127; Peak 13: Relative retention time 1.165; Peak 14: Relative retention time 1.189.

[0024] In this application, a standard fingerprint spectrum is obtained by detecting the sesame oil test solution and the reference solution. Then, based on the principles of stability of relative retention time, resolution, and good peak shape, 14 fingerprint characteristic peaks are selected. The standard fingerprint spectrum established in this application has 14 common peaks, which contain a large amount of information. Therefore, it can completely retain the chemical components in the test solution and achieve accurate monitoring of sesame oil quality.

[0025] In the sesame oil fingerprint spectrum provided in this application, peak 2 is a characteristic peak of 1,2-dilinoleic acid-3-oleic acid glyceride (OLL), peak 3 is a characteristic peak of 1,2-dilinoleic acid-3-palmitoyl glyceride (PLL), peak 4 is a characteristic peak of 1,2-dilinoleic acid-3-linoleic acid glyceride (OOL)(S), peak 6 is a characteristic peak of 1-palmitoyl-2-oleic acid-3-linoleic acid glyceride (POL), peak 8 is a characteristic peak of trioleic acid glyceride (OOO), peak 9 is a characteristic peak of 1-linoleic acid-2-oleic acid-3-stearic acid glyceride (SOL), and peak 10 is a characteristic peak of 1,2-oleic acid-3-palmitoyl glyceride (POO).

[0026] Thirdly, this application provides a method for quality control of sesame oil.

[0027] A method for quality control of sesame oil includes detecting the fingerprint spectrum of sesame oil samples using a method for constructing sesame oil fingerprint spectra, comparing the fingerprint spectrum of sesame oil samples with standard fingerprint spectra, identifying the number of common absorption peaks, and calculating the similarity.

[0028] In summary, this application has the following beneficial effects:

[0029] 1. The method for constructing sesame oil fingerprint spectrum provided in this application can effectively characterize the quality of sesame oil and achieve authenticity identification by determining the sequential order and interrelationship of fingerprint feature peaks.

[0030] 2. The method provided in this application can effectively avoid the one-sidedness of judging the overall quality of sesame oil by measuring individual chemical components. It has the advantages of simple operation, high detection accuracy and precision, and good reproducibility. Attached Figure Description

[0031] Figure 1 It is the standard fingerprint spectrum of sesame oil;

[0032] Figure 2 These are the fingerprint spectra (S2-S30) of 29 batches of sesame oil samples. Detailed Implementation

[0033] This application provides a method for constructing a sesame oil fingerprint spectrum, specifically including the following steps:

[0034] (1) Preparation of reference solution: Take 1,2-dioleoyl-3-linoleic acid glyceride, add acetone and dichloromethane in a volume ratio of 1:1 to prepare a reference solution containing 0.2 mg OOL per 1 mL;

[0035] Preparation of the test solution: Accurately weigh 0.1 g of sesame oil and place it in an Erlenmeyer flask. Accurately add 50 mL of acetone and dichloromethane in a volume ratio of 1:1, seal tightly, weigh, and sonicate at 500 W and 40 kHz for 10 min. Cool, shake well, and filter through a 0.22 μm microporous membrane. Take the filtrate to obtain the test solution.

[0036] (2) Accurately pipette 5 μL each of the test solution and the reference solution into the high performance liquid chromatograph and perform detection under the following chromatographic conditions;

[0037] The chromatographic conditions were as follows: the column was packed with octadecylsilane-bonded silica gel (two identical columns connected in series or columns of equivalent performance); the mobile phase gradient elution program was as follows: 20% dichloromethane and 80% acetonitrile during the 0-50 min period; 60% dichloromethane and 40% acetonitrile during the 50-51 min period; and 20% dichloromethane and 80% acetonitrile during the 51-65 min period. The mobile phase flow rate was 0.8-1.2 mL / min, the drift tube temperature was 75-85℃, the column temperature was 25-35℃, and the injection volume was 4.5-5.5 μL.

[0038] This application provides a quality control method for sesame oil, including detecting the fingerprint spectrum of a sesame oil sample using the sesame oil fingerprint spectrum construction method, comparing the fingerprint spectrum of the sesame oil sample with a standard fingerprint spectrum, identifying the number of common absorption peaks, and calculating the similarity.

[0039] In this application, the batch number of 1,2-dioleoyl-3-linoleic acid glyceride is 110712-201614, purchased from the China National Institutes for Food and Drug Control; the batch numbers of the sesame oil are: PCMM-MY-21.05-61, PCMM-MY-21.07-62, PCMM-MY-21.07-63, PCMM-MY-21.07-64, PCMM-MY-21.07-65, PCMM-MY-21.07-66, PCMM-MY-21.07-67, PCMM-MY-21.07-68, PCMM-MY-21.07-69, PCMM-MY-21.08-70, PCMM-MY-21.08-73, PCMM-MY-21.08-74, PCMM-MY-21.08-75, PC... MM-MY-21.08-76, PCMM-MY-21.09-77, PCMM-MY-21.09-78, PCMM-MY-21.09-79, PCMM- MY-21.09-80, PCMM-MY-21.09-81, PCMM-MY-21.09-82, PCMM-MY-21.10-83, PCMM-MY- 21.10-84, PCMM-MY-21.10-85, PCMM-MY-21.10-86, PCMM-MY-21.10-87, PCMM-MY-21. 10-88, PCMM-MY-21.11-89, PCMM-MY-21.11-90, PCMM-MY-21.11-91; the column is C18Inertsil The ODS-3 chromatographic column has dimensions of 4.6 mm × 250 mm and a diameter of 5 μm. The raw materials, reagents, solvents, etc. used in this application are all commercially available.

[0040] The present application will be further described in detail below with reference to the embodiments, test results and accompanying drawings.

[0041] Example 1

[0042] Example 1 provides a method for constructing a sesame oil fingerprint spectrum, specifically including the following steps:

[0043] (1) Preparation of reference solution: Take 1,2-dioleoyl-3-linoleic acid glyceride, add acetone and dichloromethane in a volume ratio of 1:1 to prepare a reference solution containing 0.2 mg OOL per 1 mL;

[0044] Preparation of the test solution: Accurately weigh 0.1 g of sesame oil and place it in an Erlenmeyer flask. Accurately add 50 mL of acetone and dichloromethane in a volume ratio of 1:1, seal tightly, weigh, and sonicate at 500 W and 40 kHz for 10 min. Cool, shake well, and filter through a 0.22 μm microporous membrane. Take the filtrate to obtain the test solution.

[0045] (2) Accurately pipette 5 μL each of the test solution and the reference solution into the high performance liquid chromatograph and perform detection under the following chromatographic conditions;

[0046] The chromatographic conditions were as follows: two C18 Inertsil ODS-3 columns (4.6 mm × 250 mm, 5 μm) were used in series, and the mobile phase gradient elution program was as follows: 20% dichloromethane and 80% acetonitrile during the 0-50 min period; 60% dichloromethane and 40% acetonitrile during the 50-51 min period; and 20% dichloromethane and 80% acetonitrile during the 51-65 min period.

[0047] The flow rate of the mobile phase was 1 mL / min, the temperature of the drift tube was 80℃, the column temperature was 30℃, and the injection volume was 5 μL.

[0048] The test sample and reference solution were tested using the above method. Based on the principles of relative stability (including retention time), resolution, and good peak shape, 14 characteristic peaks were selected. This characteristic chromatogram serves as the standard fingerprint chromatogram. Figure 1 As shown, there are 14 characteristic peaks. Taking peak 4 as the reference peak, the relative retention time of each characteristic peak is within ±10% of the specified value. The specified values ​​are: 0.837 (peak 1), 0.92 (peak 2), 0.943 (peak 3), 1.000 (peak 4), 1.013 (peak 5), 1.023 (peak 6), 1.047 (peak 7), 1.077 (peak 8), 1.09 (peak 9), 1.102 (peak 10), 1.113 (peak 11), 1.127 (peak 12), 1.165 (peak 13), and 1.189 (peak 14).

[0049] The characteristic chromatograms of 29 batches of sesame oil test solutions were obtained by testing them using the above method. Then, the chromatograms were analyzed using the "Traditional Chinese Medicine Chromatographic Fingerprint Similarity Evaluation System (2012 Edition)" software. Using peak 4 as the reference peak, after multi-point correction, the superimposed chromatograms of the 29 batches of samples were automatically obtained. Figure 1 ) and its comparative feature map ( Figure 2 Fourteen common peaks were identified. The similarity evaluation results of the superimposed spectra of 29 batches of samples and the characteristic spectra of the control are shown in Table 1. The similarity values ​​of the 29 batches of sesame oil test samples are in the range of 0.99-1.000.

[0050] Table 1. Similarity evaluation results of 29 batches of sesame oil

[0051]

[0052]

[0053] Precision

[0054] Accurately weigh sesame oil (batch number: PCMM-MY-21.12-91) and prepare a test solution; then, determine the test solution according to the method provided in Example 1, injecting it 6 times consecutively to obtain characteristic spectra; using peak 4 as the reference peak, calculate the relative retention time RRT and relative peak area RA of each characteristic peak, as shown in Tables 2 and 3.

[0055] Table 2 Precision assessment - Relative Retention Time (RRT) test results

[0056]

[0057]

[0058] Table 3 Precision Examination - Relative Peak Area (RA) Detection Results

[0059]

[0060] According to the test results in Tables 2 and 3, for the same test solution, after 6 consecutive injections, the RSD value of the relative retention time (RRT) of each characteristic peak is less than 1%, which meets the requirements; the RSD% of the relative peak area (RA) of characteristic peaks 1, 2, 4, 6, and 8 is less than 3%, which meets the requirements.

[0061] Repeatability

[0062] Accurately weigh sesame oil (batch number: PCMM-MY-21.12-91) and prepare 6 test solutions in parallel. Then, measure the test solutions according to the method provided in Example 1 to obtain characteristic spectra. Using peak 4 as the reference peak, calculate the relative retention time RRT and relative peak area RA of each characteristic peak, as shown in Tables 4 and 5.

[0063] Table 4 Repeatability Test - Relative Retention Time (RRT) Results

[0064]

[0065]

[0066] Table 5 Repeatability Test - Relative Peak Area (RA) Detection Results

[0067]

[0068] According to the test results in Tables 4 and 5, for the fingerprint spectra of the six test solutions, the relative retention time RSD of the 14 characteristic peaks was between 0.0% and 0.1% (<1%), and the relative peak area RSD was between 0.0% and 1% (<3%). Therefore, this indicates that the method for constructing the sesame oil fingerprint spectra provided in this application has good reproducibility and meets the requirements for method reproducibility in the 2020 edition of the Chinese Pharmacopoeia, Part IV, 9101 (Guiding Principles for Validation of Analytical Methods for Drug Quality Standards).

[0069] Examples 2-5

[0070] Examples 2-5 each provide a method for constructing a sesame oil fingerprint spectrum.

[0071] Examples 2-5 were performed according to the method of Example 1, except that the detection conditions in the high performance liquid chromatography separation and detection were as shown in Table 6 below.

[0072] Comparative Examples 1-2

[0073] Comparative Examples 1-2 provide a method for constructing a sesame oil fingerprint spectrum.

[0074] Comparative Examples 1-2 were performed according to the method of Example 1, except that the detection conditions in the high performance liquid chromatography separation and detection were as shown in Table 6 below.

[0075] Table 6. Detection conditions in Examples 2-5 and Comparative Examples 1-2

[0076]

[0077] Comparative Example 3

[0078] Comparative Example 3 provides a method for constructing a fingerprint spectrum of sesame oil.

[0079] Comparative Example 3 was performed following the method of Example 1, except that the gradient elution program of the mobile phase in the high-performance liquid chromatography (HPLC) separation and detection was as follows:

[0080] The mobile phase gradient elution program for Comparative Example 3 was as follows: 20% hexane and 80% acetonitrile during the period of 0-50 min; 60% hexane and 40% acetonitrile during the period of 50-51 min; and 20% hexane and 80% acetonitrile during the period of 51-65 min; with a mobile phase flow rate of 1 mL / min.

[0081] Comparative Example 4

[0082] Comparative Example 4 provides a method for constructing a sesame oil fingerprint spectrum.

[0083] Comparative Example 4 was performed following the method of Example 1, except that the gradient elution program of the mobile phase in the high-performance liquid chromatography (HPLC) separation and detection was as follows:

[0084] The mobile phase gradient elution program for Comparative Example 4 was as follows: 30% dichloromethane and 70% acetonitrile during the period of 0-45 min; 50% dichloromethane and 50% acetonitrile during the period of 45-50 min; and 30% dichloromethane and 70% acetonitrile during the period of 50-60 min.

[0085] Test results

[0086] Fingerprint chromatograms were constructed using the methods provided in Examples 1-5 and Comparative Examples 1-4, and analyzed using the "Traditional Chinese Medicine Chromatographic Fingerprint Similarity Evaluation System (2012 Edition)" software. Peak 4 was used as the reference peak for similarity evaluation, and the results are shown in Table 7 below.

[0087] Table 7. Similarity between fingerprint spectra obtained in Examples 1-5 and Comparative Examples 1-4 and standard fingerprint spectra.

[0088]

[0089]

[0090] According to the detection results of Examples 1-5 and Comparative Examples 1-2, at a flow rate of 0.8-1.2 mL / min and a column temperature of 25-35℃, the similarity values ​​of the sesame oil test samples were between 0.999 and 1.000. Therefore, this demonstrates that the method for constructing the sesame oil fingerprint spectrum provided in this application has good robustness.

[0091] The detection results of Examples 1 and Comparative Examples 3-4 show that the fingerprint spectrum obtained using the mobile phase gradient elution program of Example 1 has a similarity of 1 with the standard fingerprint spectrum, while the fingerprint spectrum obtained using the mobile phase gradient elution program of Comparative Examples 3-4 has a similarity of only 0.484-0.672 with the standard fingerprint spectrum. Therefore, this demonstrates that the mobile phase elution program provided in this application has good separation effect and excellent accuracy in detecting sesame oil quality.

[0092] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A method for constructing a sesame oil fingerprint spectrum, characterized in that, Includes the following steps: (1) Preparation of reference solution and test solution; The reference standard is 1,2-dioleoyl-3-linoleic acid glyceride; the concentration of 1,2-dioleoyl-3-linoleic acid glyceride in the reference standard solution is 0.1-0.2 mg / mL; The preparation method of the test solution is as follows: the sesame oil sample to be tested is extracted with an organic solvent, wherein the organic solvent is acetone and dichloromethane with a volume ratio of 1:1; the extraction method is ultrasound, wherein the power of the ultrasound is 400-600W, the frequency is 35-45kHz, and the extraction time is 10-20min. (2) The reference solution and the test solution were injected into a liquid chromatograph, and high performance liquid chromatography separation and detection were performed using a chromatographic column with octadecylsilane bonded silica gel packing, a mobile phase gradient elution method and an evaporative light detector to obtain a fingerprint spectrum; The mobile phase gradient elution program was as follows: 20% dichloromethane and 80% acetonitrile during the 0-50 min period; 60% dichloromethane and 40% acetonitrile during the 50-51 min period; and 20% dichloromethane and 80% acetonitrile during the 51-65 min period. The flow rate of the mobile phase was 0.8-1.2 mL / min. The sesame oil fingerprint spectrum contains 14 characteristic peaks; peak 2 is a characteristic peak of 1,2-dilinoleic acid-3-oleic acid glyceride, peak 3 is a characteristic peak of 1,2-dilinoleic acid-3-palmitic acid glyceride, peak 4 is a characteristic peak of 1,2-dioleic acid-3-linoleic acid glyceride, peak 6 is a characteristic peak of 1-palmitic acid-2-oleic acid-3-linoleic acid glyceride, peak 8 is a characteristic peak of trioleic acid glyceride, peak 9 is a characteristic peak of 1-linoleic acid-2-oleic acid-3-stearic acid glyceride, and peak 10 is a characteristic peak of 1,2-oleic acid-3-palmitic acid glyceride.

2. The construction method according to claim 1, characterized in that, In the high-performance liquid chromatography separation and detection, the drift tube temperature is 75-85℃, the column temperature is 25-35℃, and the injection volume is 4.5-5.5μL.

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