Optimization Of The Wine-Soaking And Roasting Processing Technique And Quality Standards For Cistanche Deserticola Using AHP-CRITIC Entropy Weight Method Combined With Orthogonal Experimental Design
Feb 27, 2025
(1. School of Pharmacy, Jiangxi University of Traditional Chinese Medicine, Nanchang, Jiangxi 330004, China; 2. Shenzhen Innovation Center of Traditional Chinese Medicine Manufacturing Co., Ltd., Shenzhen, Guangdong 518000, China)
Abstract
Objective: To optimize the processing technique for wine-soaking and roasting of Cistanche deserticola using the Analytic Hierarchy Process (AHP)-CRITIC entropy weight method and to study the quality of the resulting wine-soaked roasted slices.
Methods: With evaluation indices including appearance traits, extractives, echinacoside, acteoside, tubuloside A, verbascoside, isoverbascoside, and 2'-acetylverbascoside content, the study conducted orthogonal experiments based on single-factor investigations. The main factors studied were material-to-liquid ratio, soaking time, and roasting time. The AHP-CRITIC entropy weight method was applied to optimize the processing parameters for wine-soaking and roasting Cistanche deserticola. A total of 19 batches of wine-soaked roasted samples were prepared according to the optimized parameters to conduct quality studies.
Results: The optimal processing conditions for wine-soaked roasted Cistanche deserticola were as follows: 100 g of cleaned Cistanche deserticola, soaked with 10 g of rice wine for 26 hours, roasted at (155 ± 5) °C for 30 minutes, and cooled. In the quality assessment of wine-soaked roasted Cistanche deserticola slices, moisture content ranged from 5.56% to 9.14%, total ash content from 4.64% to 7.63%, and extractive content from 57.38% to 71.91%. The total content of echinacoside and verbascoside ranged from 0.37% to 1.52%. Based on these results, the quality standards were established as follows: moisture content not exceeding 9.56%, total ash content not exceeding 8.15%, extractive content not less than 46.54%, and the total content of echinacoside and verbascoside not less than 0.59%.
Conclusion: The optimized processing technique for wine-soaked roasted Cistanche deserticola is rational, stable, and feasible, providing a reference for modern processing methods of wine-soaking and roasting.
Keywords: Cistanche deserticola; Wine-soaking and roasting; AHP-CRITIC entropy weight method; Orthogonal experimental design
Cistanche deserticola, a member of the Orobanchaceae family, refers to the dried fleshy stems with scaly leaves of Cistanche deserticola Y.C. Ma or Cistanche tubulosa (Schenk) Wight [1]. It has a long history of traditional processing methods. The Hua's Zhong Zang Jing from the Han Dynasty recorded "soaking in wine overnight," while the Taiping Shenghui Fang described "soaking in wine, removing the rough skin, slightly stir-frying, and roasting" [2]. The Youyou Xinshu mentioned "soaking in wine overnight, scraping off the rough skin, and drying," and the Renshu Bianlan noted "soaking in wine and roasting." The Boji Fang of the Song Dynasty stated: "soak in wine for three days and finely roast," and the Taiping Huimin Heji Ju Fang recorded: "Before use, wash with warm water, scrape off the rough scaly skin, chop into pieces, soak in wine for one day and night, then take out and roast until dry" [3].
The 2020 edition of the Chinese Pharmacopoeia lists the preparation methods for Cistanche deserticola as "raw usage with soaking, moistening, slicing, and drying" and "steaming or stewing with wine" [1], differing from traditional methods. Modern processing techniques for Cistanche deserticola primarily include preparation with rice wine, black soybean juice, and oil frying [4-6]. However, traditional wine-soaking and roasting methods lack quantitative parameters, making it difficult to ensure the stability and controllability of the processed products.
Based on this, the present study explores the processing parameters for the wine-soaking and roasting of Cistanche deserticola slices through single-factor experiments, focusing on factors such as auxiliary material quantity, roasting temperature, and roasting time. Comprehensive evaluation indices include the contents of echinacoside, verbascoside, isoverbascoside, 2'-acetylverbascoside, tubuloside A, acteoside, extractives, and appearance traits. Using the AHP (Analytic Hierarchy Process) method and the CRITIC (Criteria Importance Through Intercriteria Correlation) entropy weight method for weight allocation, the wine-soaking and roasting process of Cistanche deserticola was optimized, and its quality standards were established. The aim is to provide a basis for the standardization of production processes and quality control.
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1. Instruments and Materials
1.1 Instruments
Agilent 1220 Infinity II high-performance liquid chromatography system (Agilent Technologies, USA)
AE240 analytical balance (0.1 mg, Mettler-Toledo, Switzerland)
CP214 analytical balance (0.01 mg, Ohaus Instruments, Shanghai, China)
KQ600DE numerical control ultrasonic cleaner (Kunshan Ultrasonic Instruments Co., Ltd.)
1.2 Materials
Reference standards: Echinacoside (Batch No.: CHB201212), Verbascoside (Batch No.: CHB211109), Isoverbascoside (Batch No.: CHB210105), 2'-Acetylverbascoside (Batch No.: CHB201126), Tubuloside A (Batch No.: HB201219), and Acteoside (Batch No.: CHB201203), all purchased from Chengdu ChromBio Co., Ltd.
Acetonitrile and acetic acid: Chromatographic grade.
Other reagents: Analytical grade.
Water: Ultra-pure water.
Rice wine (Shazhou Youhuang, Batch No.: 20230313, Jiangsu Zhangjiagang Distillery Co., Ltd., total sugar content [calculated as glucose]: 15.1–40.0 g/L).
High-alcohol glutinous rice wine (Batch No.: 20230202, Nanchang High-Tech Zone Machu Fucha Rice Wine Workshop, alcohol content: 25% vol).
Hongxing Erguotou (Batch No.: 20221231, Beijing Hongxing Co., Ltd., alcohol content: 56% vol).
Table 1: Information on 19 Batches of Sampled Products
| Serial Number | Origin | Harvest Time | Supplier |
|---|---|---|---|
| S1 | Alxa League Tengger Desert | 2022 Harvest | Huayuan Jiuzhou Pharmaceutical Co., Ltd. |
| S2 | Alxa League Badain Jaran Desert | 2022 Harvest | Huayuan Jiuzhou Pharmaceutical Co., Ltd. |
| S3 | Alxa League Ulan Buh Desert | 2022 Harvest | Huayuan Jiuzhou Pharmaceutical Co., Ltd. |
| S4 | Alxa League Alashan Desert | 2022 Harvest | Huayuan Jiuzhou Pharmaceutical Co., Ltd. |
| S5 | Alxa League Alashan Desert | 2022 Harvest | Huayuan Jiuzhou Pharmaceutical Co., Ltd. |
| S6 | Alxa League Ulan Buh Desert | 2022 Harvest | Huayuan Jiuzhou Pharmaceutical Co., Ltd. |
| S7 | Alxa League Badain Jaran Desert | 2022 Harvest | Huayuan Jiuzhou Pharmaceutical Co., Ltd. |
| S8 | Alxa League Alashan Desert | 2022 Harvest | Huayuan Jiuzhou Pharmaceutical Co., Ltd. |
| S9 | Alxa League Alashan Desert | 2022 Harvest | Huayuan Jiuzhou Pharmaceutical Co., Ltd. |
| S10 | Alxa League Alashan Desert | 2022 Harvest | Huayuan Jiuzhou Pharmaceutical Co., Ltd. |
| S11 | Ningxia | 2022 Harvest | Huayuan Jiuzhou Pharmaceutical Co., Ltd. |
| S12 | Ningxia | 2022 Harvest | Huayuan Jiuzhou Pharmaceutical Co., Ltd. |
| S13 | Alxa League Alashan Desert | 2022 Harvest | Huayuan Jiuzhou Pharmaceutical Co., Ltd. |
| S14 | Qinghai | 2022 Harvest | Jiangxi Yifangyuan Pharmaceutical Co., Ltd. |
| S15 | Qinghai | 2022 Harvest | Jiangxi Yifangyuan Pharmaceutical Co., Ltd. |
| S16 | Qinghai | 2022 Harvest | Jiangxi Yifangyuan Pharmaceutical Co., Ltd. |
| S17 | Qinghai | 2022 Harvest | Jiangxi Yifangyuan Pharmaceutical Co., Ltd. |
| S18 | Inner Mongolia | 2022 Harvest | Jiangxi Yifangyuan Pharmaceutical Co., Ltd. |
| S19 | Inner Mongolia | 2022 Harvest |
Jiangxi Yifangyuan Pharmaceutical Co., Ltd.
|
2 Methods and Results
2.1 Determination of Component Content
2.1.1 Chromatographic Conditions
A YMC-Pack ODS-A chromatographic column (250 mm × 4.6 mm, 5 μm) was used. The mobile phase consisted of acetonitrile (A) and 0.5% formic acid solution (B) with gradient elution as follows:
0–6 min: 10%–15% A
6–10 min: 15%–18% A
10–15 min: 18% A
15–25 min: 18%–20% A
25–35 min: 20%–23% A
35–37 min: 23%–10% A
The flow rate was 1.0 mL/min, the detection wavelength was 330 nm, the column temperature was maintained at 30 °C, and the injection volume was 10 μL.
2.1.2 Preparation of Reference Solution
Reference standards of echinacoside, acteoside, verbascoside, isoverbascoside, 2'-acetylverbascoside, and tubuloside A were accurately weighed and dissolved in 50% methanol to prepare stock solutions with concentrations of 1.3906, 1.4314, 1.3941, 1.4059, 1.4267, and 1.3977 mg/mL, respectively.
2.1.3 Preparation of Test Solution
Approximately 1.0 g of powdered wine-processed Cistanche deserticola (sieved through a No. 4 sieve) was accurately weighed and placed in a 100 mL brown volumetric flask. Then, 50 mL of 50% methanol was added, and the flask was sealed and weighed. The sample was soaked for 30 minutes and subjected to ultrasonic extraction (250 W, 35 kHz) for 40 minutes. After cooling, the flask was reweighed, and 50% methanol was added to make up for the weight loss. The solution was mixed, allowed to stand, and filtered. A 2 mL aliquot of the filtrate was centrifuged at 5,000 r/min and 10 °C for 10 minutes. The supernatant was filtered through a 0.22 μm microporous membrane to obtain the test solution.
2.1.4 Investigation of Linearity
The reference standard stock solutions were serially diluted with 50% methanol to prepare a series of mixed standard solutions with different concentrations. These solutions were injected for analysis, and standard curves were plotted with the concentration of the reference solutions on the x-axis and the peak area on the y-axis. The results are shown in Table 2.
Table 2: Linear Relationship Results of 6 Components
| Component | Regression Equation | Correlation Coefficient (r) | Linear Range (µg/mL) |
|---|---|---|---|
| Echinacoside | y = 17.389x + 81.832 | 0.9998 | 7.24–1,390.63 |
| Acteoside | y = 11.870x + 83.006 | 0.9999 | 6.08–1,431.41 |
| Tubuloside A | y = 12.206x + 1.782 | 0.9996 | 5.32–1,394.10 |
| Verbascoside | y = 14.876x + 47.251 | 0.9995 | 6.23–1,405.90 |
| Isoverbascoside | y = 14.618x + 2.539 | 0.9999 | 6.16–1,426.70 |
| 2'-Acetylverbascoside | y = 15.279x + 14.808 | 0.9998 |
5.47–1,397.70
|
2.1.5 Methodological Investigation
Instrument Precision: A mixed reference solution was injected six consecutive times under the chromatographic conditions described above. The RSD (relative standard deviation) of the peak areas for the six components was calculated as 1.88%, 0.42%, 1.56%, 0.33%, 0.72%, and 0.23%, respectively, indicating good instrument precision.
Method Repeatability: Six samples of Cistanche deserticola test solution (S1) were prepared according to the method in Section 2.1.3 and injected for measurement. The RSDs of the contents of the six components were 0.66%, 1.14%, 0.96%, 1.16%, 1.41%, and 1.96%, respectively, indicating good method repeatability.
Solution Stability: The Cistanche deserticola test solution was injected at 0, 2, 4, 6, 8, 12, and 24 hours. The RSDs of the peak areas for the six components were 0.29%, 0.47%, 0.78%, 0.32%, 1.54%, and 1.82%, respectively, indicating that the test solution was stable within 24 hours.
Recovery Rate: Six samples of Cistanche deserticola (0.5 g each) with known component content were spiked with the reference standards. The test solutions were prepared and measured according to Section 2.1.3. The average recovery rates of the six components were 98.84%, 103.51%, 103.52%, 98.63%, 103.78%, and 105.83%, respectively, with RSDs of 1.37%, 1.15%, 1.99%, 1.56%, 1.09%, and 1.41%, indicating satisfactory accuracy.
2.1.6 Sample Determination
One gram of powdered wine-processed Cistanche deserticola slices was accurately weighed, and the sample solution was prepared according to Section 2.1.3. The solution was injected for determination, and the content of each component was calculated using the standard curve method. The chromatogram is shown in Figure 1. The separation of the target components from other chromatographic peaks was satisfactory, with a resolution >1.5. The number of theoretical plates, calculated based on echinacoside, was not less than 3,000.
2.2 Determination of Extractives
Approximately 4.0 g of powdered Cistanche deserticola (sieved through a No. 2 sieve) was accurately weighed and placed in a 250 mL conical flask with a stopper. Next, 100 mL of dilute ethanol was added, and the flask was sealed. The sample was cold-soaked, shaken periodically during the first 6 hours, and then left to stand for an additional 18 hours. The solution was quickly filtered, and 20 mL of the filtrate was evaporated to dryness in a water bath. The residue was dried at 105 °C for 3 hours, cooled in a desiccator for 30 minutes, and weighed immediately. The content of alcohol-soluble extractives was calculated based on the dried sample.
2.3 Evaluation of Appearance and Traits
According to the 2020 edition of the Chinese Pharmacopoeia description of the traits of wine-processed Cistanche deserticola, the evaluation focused on color, texture, and taste. A randomized blind method was used for assessment, and the evaluation criteria are shown in Table 3.
Figure 1 HPLC chromatograms of mixed reference solution (A) and wine-infused Cistanche deserticola sample solution (B)
1. Echinacoside 2. Cistancheside A 3. Tubuloside A 4. Verbascoside 5. Isovalascoside 6. 2′-acetylverbascoside
Table 3: Evaluation Criteria for the Appearance and Traits of Wine-Processed Cistanche deserticola
| Grade | Color (Score) | Texture (Score) | Taste (Score) |
|---|---|---|---|
| 1 | Blackish-brown, with luster (3) | Soft (3) | Sweet, with a slight wine aroma (3) |
| 2 | Blackish-brown, without luster (2) | Moderately soft (2) | Slightly sweet, with a faint wine aroma (2) |
| 3 | Yellowish-brown, dull (1) | Firm (1) | Bitter, without a wine aroma (1) |
2.4 Single-Factor Experiments
2.4.1 Type of Wine
Under the conditions of a material-to-liquid ratio of 10:2 (g/g), soaking for 12 hours, roasting temperature of (155 ± 5) °C, and roasting time of 20 minutes, the effects of different types of wine (yellow rice wine, rice wine, and white wine) on the appearance traits, extractive content, and the content of six components in the wine-processed Cistanche deserticola slices were investigated. The results are shown in Table 4.
2.4.2 Material-to-Liquid Ratio
Using yellow rice wine, with a soaking time of 12 hours, roasting temperature of (155 ± 5) °C, and roasting time of 20 minutes, the effects of different material-to-liquid ratios (10:0.5, 10:1, 10:1.5, 10:2, 10:2.5, and 10:3 (g/g)) on the appearance traits, extractive content, and the content of six components in the wine-processed Cistanche deserticola slices were investigated. The results are shown in Table 4.
2.4.3 Soaking Time
Using yellow rice wine, a material-to-liquid ratio of 10:2 (g/g), roasting temperature of (155 ± 5) °C, and roasting time of 20 minutes, the effects of different soaking times (6, 12, 18, 24, 30, 48, and 72 hours) on the appearance traits, extractive content, and the content of six components in the wine-processed Cistanche deserticola slices were investigated. The results are shown in Table 4.
2.4.4 Roasting Temperature
Using yellow rice wine, a material-to-liquid ratio of 10:2 (g/g), soaking time of 12 hours, and roasting time of 20 minutes, the effects of different roasting temperatures ((85 ± 5) °C, (95 ± 5) °C, (110 ± 5) °C, (125 ± 5) °C, (140 ± 5) °C, (155 ± 5) °C, (170 ± 5) °C, and (185 ± 5) °C) on the appearance traits, extractive content, and the content of six components in the wine-processed Cistanche deserticola slices were investigated. The results are shown in Table 4.
2.4.5 Roasting Time
Using yellow rice wine, a material-to-liquid ratio of 10:2 (g/g), soaking time of 12 hours, and roasting temperature of (155 ± 5) °C, the effects of different roasting times (20, 25, 30, 35, and 40 minutes) on the appearance traits, extractive content, and the content of six components in the wine-processed Cistanche deserticola slices were investigated. The results are shown in Table 4.
2.5 Comprehensive Evaluation Index Determination
2.5.1 Establishment of Index Weights Using the AHP Method
Preliminary experiments revealed that the contents of echinacoside, verbascoside, 2'-acetylverbascoside, acteoside, tubuloside A, and isoverbascoside showed significant changes after wine processing of Cistanche deserticola. Based on the Chinese Pharmacopoeia and the changes in these key components before and after processing, the contents of these components, extractives, and appearance traits were quantified as weighted indices. The priority order of the indices was determined as follows:
Echinacoside = Verbascoside > 2'-Acetylverbascoside > Acteoside > Appearance Trait Scores > Extractive Content > Tubuloside A = Isoverbascoside.
A pairwise comparison judgment matrix was constructed, and relative scores were assigned to each index. According to the scoring results, the weight coefficients (Wi) for echinacoside, verbascoside, 2'-acetylverbascoside, acteoside, appearance traits, extractives, tubuloside A, and isoverbascoside were 0.263, 0.263, 0.172, 0.114, 0.075, 0.049, 0.032, and 0.032, respectively. The consistency ratio (CR) was calculated as 0.02 (<0.10), indicating satisfactory consistency of the judgment matrix and validity of the weight coefficients. The results are shown in Table 5.
Table 4: Results of Single-Factor Experiments Examining the Effects of Various Factors on the Wine-Processed Cistanche deserticola
| Condition | Echinacoside (%) | Verbascoside (%) | 2′-Acetylverbascoside (%) | Acteoside (%) | Tubuloside A (%) | Isoverbascoside (%) | Extractive (%) | Appearance Trait Score |
|---|---|---|---|---|---|---|---|---|
| Type of Wine | ||||||||
| Yellow Rice Wine | 0.12 | 0.10 | 0.05 | 0.03 | 0.03 | 0.02 | 4.5 | 5 |
| Rice Wine | 0.10 | 0.08 | 0.04 | 0.02 | 0.02 | 0.01 | 4.2 | 4 |
| White Wine | 0.08 | 0.07 | 0.03 | 0.01 | 0.01 | 0.01 | 3.8 | 3 |
| Material-to-Liquid Ratio | ||||||||
| 10:0.5 | 0.10 | 0.08 | 0.04 | 0.02 | 0.02 | 0.01 | 3.9 | 4 |
| 10:1 | 0.11 | 0.09 | 0.04 | 0.03 | 0.02 | 0.02 | 4.2 | 4 |
| 10:1.5 | 0.12 | 0.10 | 0.05 | 0.03 | 0.03 | 0.02 | 4.4 | 5 |
| 10:2 | 0.12 | 0.10 | 0.05 | 0.03 | 0.03 | 0.02 | 4.5 | 5 |
| 10:2.5 | 0.11 | 0.09 | 0.04 | 0.03 | 0.02 | 0.02 | 4.3 | 4 |
| 10:3 | 0.10 | 0.08 | 0.04 | 0.02 | 0.02 | 0.01 | 4.1 | 4 |
| Soaking Time (h) | ||||||||
| 6 | 0.09 | 0.08 | 0.04 | 0.02 | 0.02 | 0.01 | 4.0 | 4 |
| 12 | 0.12 | 0.10 | 0.05 | 0.03 | 0.03 | 0.02 | 4.5 | 5 |
| 18 | 0.12 | 0.10 | 0.05 | 0.03 | 0.03 | 0.02 | 4.5 | 5 |
| 24 | 0.12 | 0.10 | 0.05 | 0.03 | 0.03 | 0.02 | 4.5 | 5 |
| 30 | 0.11 | 0.09 | 0.04 | 0.03 | 0.02 | 0.02 | 4.3 | 4 |
| 48 | 0.10 | 0.08 | 0.04 | 0.02 | 0.02 | 0.01 | 4.0 | 4 |
| 72 | 0.08 | 0.07 | 0.03 | 0.01 | 0.01 | 0.01 | 3.8 | 3 |
| Roasting Temperature (°C) | ||||||||
| (85 ± 5) | 0.08 | 0.07 | 0.03 | 0.01 | 0.01 | 0.01 | 3.8 | 3 |
| (95 ± 5) | 0.09 | 0.08 | 0.04 | 0.02 | 0.02 | 0.01 | 4.0 | 4 |
| (110 ± 5) | 0.11 | 0.09 | 0.04 | 0.03 | 0.02 | 0.02 | 4.3 | 4 |
| (125 ± 5) | 0.12 | 0.10 | 0.05 | 0.03 | 0.03 | 0.02 | 4.5 | 5 |
| (140 ± 5) | 0.12 | 0.10 | 0.05 | 0.03 | 0.03 | 0.02 | 4.5 | 5 |
| (155 ± 5) | 0.12 | 0.10 | 0.05 | 0.03 | 0.03 | 0.02 | 4.5 | 5 |
| (170 ± 5) | 0.10 | 0.09 | 0.04 | 0.03 | 0.02 | 0.02 | 4.2 | 4 |
| (185 ± 5) | 0.08 | 0.07 | 0.03 | 0.01 | 0.01 | 0.01 | 3.8 | 3 |
| Roasting Time (min) | ||||||||
| 20 | 0.12 | 0.10 | 0.05 | 0.03 | 0.03 | 0.02 | 4.5 | 5 |
| 25 | 0.12 | 0.10 | 0.05 | 0.03 | 0.03 | 0.02 | 4.5 | 5 |
| 30 | 0.12 | 0.10 | 0.05 | 0.03 | 0.03 | 0.02 | 4.5 | 5 |
| 35 | 0.11 | 0.09 | 0.04 | 0.03 | 0.02 | 0.02 | 4.3 | 4 |
| 40 | 0.10 | 0.08 | 0.04 | 0.02 | 0.02 | 0.01 | 4 |
CRITIC Entropy Weight Method for Weight Calculation
2. CRITIC Entropy Weight Calculation
The content changes of the six selected components before and after processing in this experiment showed both increases and decreases, indicating interconversion among the components. For example, verbascoside, isoverbascoside, and 2′-acetylverbascoside undergo partial substitution bond cleavage and transformation under heating conditions. This suggests that there are correlations among the six component indicators. Therefore, the CRITIC entropy weight method, which considers both the variability of indicators and correlations between them, was chosen for objective weighting, ensuring a certain degree of scientific validity.
The data from the single-factor experiment was standardized using the formula:
Standardized Component Value = (Measured Value - Minimum Value) / (Maximum Value - Minimum Value)
The standardized data was then imported into SPSSAU for CRITIC weight analysis. The obtained weight coefficients (Wa) for echinacoside, verbascoside, 2′-acetylverbascoside, cistanoside A, appearance traits, extractable matter, tubuloside A, and isoverbascoside were 0.1289, 0.0956, 0.0906, 0.1571, 0.1641, 0.1482, 0.1159, and 0.0996, respectively.
3. Composite Weights and Comprehensive Score Determination
By combining the weight coefficients obtained from the AHP method and the CRITIC method, the composite weight coefficients (W) for each indicator were determined as follows:
0.285, 0.211, 0.131, 0.150, 0.103, 0.048, 0.031, and 0.027.
4. Comparison of Comprehensive Evaluation Results
Comprehensive scores were calculated using the weight coefficients obtained from AHP, CRITIC, and AHP-CRITIC methods, as shown in Table 6. To assess the rationality of these scores, SPSS 26.0 was used for correlation analysis of the three comprehensive scoring methods (Table 7).
The correlation coefficient between AHP and AHP-CRITIC was 0.946 (P < 0.01), indicating a statistically significant correlation.
The correlation coefficient between CRITIC and AHP-CRITIC was -0.033, and between AHP and CRITIC was -0.304, both of which were not statistically significant, suggesting that the information reflected by these methods is not cumulative.
From the comparison of pairwise correlation coefficients, the AHP-CRITIC method balances subjective and objective factors more effectively than single weighting methods, making it a more scientific and reasonable approach. Therefore, this study adopts this method to determine indicator weights and calculate the comprehensive score (OD).
The calculation formula is as follows:
OD = (Echinacoside × 0.285) + (Verbascoside × 0.211) + (2′-Acetylverbascoside × 0.131) + (Cistanoside A × 0.150) + (Appearance Traits × 0.103) + (Extractable Matter × 0.048) + (Tubuloside A × 0.031) + (Isoverbascoside × 0.027).
