Method for identifying silkworm cocoon silk bred by feed

Abstract

The invention relates to the technical field of textile raw material identification, in particular to an identification method of feed-bred silkworm cocoon silks, the free radical scavenging capacity of the feed-bred silkworm cocoon silks is remarkably different from that of common mulberry leaf-bred silkworm cocoon silks, and the feed-bred silkworm cocoon silks and the mulberry leaf-bred silkworm cocoon silks are identified by measuring the ABTS free radical scavenging rate. The detection method provided by the invention is superior to a conventional detection method, and has high accuracy and strong practicability.

Description

Technical Field

[0001] The invention relates to the technical field of textile raw material identification, in particular to a method for identifying silkworm cocoon silk bred with feed. Background Art

[0002] There are significant differences in the physical properties of silk cocoons raised on feed and silk cocoons raised on mulberry leaves. Silk cocoons raised on mulberry leaves usually have better gloss, fiber strength and toughness. This makes silk cocoons raised on mulberry leaves more suitable for reeling high-grade raw silk, becoming the first choice for high-end silk raw materials and suitable for application scenarios that require high-quality materials. However, traditional silkworm breeding with mulberry leaves is highly seasonal and limited by the varying quality of mulberry leaves, making it difficult to ensure large-scale production throughout the year. The use of artificial feed factory-based silkworm breeding can achieve large-scale production throughout the year, the feed environment and feed ingredients can be precisely controlled, and the production has higher quality stability. Therefore, many unscrupulous merchants use silk cocoons raised on feed to impersonate silk cocoons raised on mulberry leaves to obtain more economic benefits, which is not conducive to the standardization of raw silk market transactions and the control of raw silk product quality.

[0003] At present, the distinction between silkworm cocoons raised with mulberry leaves and silkworm cocoons raised with feed has become a difficult problem that needs to be solved in the silk industry. The significance of distinguishing between silkworm cocoons raised with mulberry leaves and silkworm cocoons raised with feed is to facilitate silk weaving companies to select materials on demand to meet different market demands, standardize market transactions, and promote the long-term sustainable development of the full-age feed factory silkworm industry.

[0004] The methods reported in China that can distinguish between silkworms raised on mulberry leaves and silkworms raised on feed are mainly based on the differences in physical properties such as cocoon quality and silk properties. These methods are scientific to a certain extent, but the relevant properties of raw silk reeled from different origins and manufacturers vary greatly, especially the subsequent processing of cocoons. Therefore, the detection methods for silkworms raised on feed and silkworms raised on mulberry leaves based on these physical properties are not universal and not practical. Summary of the invention

[0005] Traditionally, mulberry leaves have been the main food source for silkworms. Mulberry leaves are rich in a variety of natural antioxidant substances that can remove free radicals. These substances can be partially transferred to silkworm cocoons after being eaten by silkworms. Mulberry leaf-grown silkworm cocoons contain rich polyphenol antioxidant substances, which give them strong antioxidant capacity. Their antioxidant properties are far superior to those of feed-grown silkworm cocoons. Based on this, the present invention proposes a method for identifying mulberry leaf-grown silkworm cocoons. By measuring ABTS +· The free radical scavenging rate value is used to identify the type of silk.

[0006] A method for identifying cocoon silk produced by silkworms raised on feed, comprising cocoon silk produced by silkworms raised on feed, wherein the cocoon silk produced by silkworms raised on feed is produced by silkworms of all ages eating feed, and the content of polyphenol antioxidants in the cocoon silk produced by silkworms raised on feed is lower than that in the cocoon silk produced by silkworms raised on mulberry leaves.

[0007] Preferably, the identification method is to detect the scavenging performance of the sample to be tested on ABTS free radicals to reflect the antioxidant performance of the sample to be tested, and determine whether the sample to be tested is mulberry leaf silk or feed silk by the scavenging performance of ABTS free radicals.

[0008] Preferably, the content of the polyphenol antioxidant substances is detected by ABTS free radical scavenging ability, and the detection steps of the ABTS free radical scavenging ability are as follows:

[0009] S1, prepare 7mmol / L ABTS solution and 2.45mmol / L potassium persulfate solution with deionized water respectively, and mix them in a volume ratio of 1:1. The resulting mixed solution is stored in the dark at room temperature for 14±2h to obtain ABTS + Storage solution;

[0010] S2, prepare a 0.1 mol / L phosphate buffer solution with a pH of 7.4 using disodium hydrogen phosphate dihydrate and sodium dihydrogen phosphate. + Dilute the stock solution 45 ± 5 times so that its absorbance at 733 nm is 0.700 ± 0.025 to obtain ABTS + ·Assay solution;

[0011] S3, add 1 mL of anhydrous ethanol to 60 mg of the sample to be tested, and then add 20 mL of ABTS in the dark. +· The test solution was sealed and ultrasonically vibrated for 30 seconds, stored in a constant temperature water bath at 30°C in the dark for 6 minutes, taken out and filtered, and the supernatant was retained;

[0012] S4, calibrate to zero with deionized water, measure the absorbance of the supernatant at 734nm, measure each sample 3 times, take the average value and record it as A 样品 ;

[0013] S5, the blank control group used the same treatment conditions and experimental methods, by adding 20mL ABTS to 1mL anhydrous ethanol + The mixed solution without silkworm cocoons was obtained by measuring the absorbance at 734 nm and recorded as A 空白 ;

[0014] S6, calculate the sample ABTS according to the following formula + Clearance rate.

[0015] ABTS + · Clearance rate / % = (A 空白 -A 样品 ) / A 空白 ×100 (1)

[0016] Preferably, the ABTS of the sample to be tested+ When the removal rate is within the range of 45-58%, the sample is determined to be feed-raised silkworm cocoon silk; otherwise, the sample is determined to be mulberry leaf-raised silkworm cocoon silk.

[0017] Compared with the prior art, the present invention determines ABTS + The free radical scavenging rate can quickly distinguish between mulberry leaf-reared silkworm cocoons and feed-reared silkworm cocoons, making it easier for silk weaving companies to select materials on demand to meet different market demands, standardize market transactions, and promote the long-term sustainable development of the full-age feed factory silkworm industry. Especially when the relevant properties of raw silk reeled from different origins and manufacturers are quite different, and the antioxidant properties of silk are affected, the ABTS test can still be used to determine the free radical scavenging rate. +· The free radical scavenging rate can accurately distinguish the cocoons of silkworms raised with mulberry leaves from those raised with feed. The detection method of the invention is superior to conventional detection methods, has high accuracy and strong practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a graph showing the antioxidant activity of silkworm cocoons grown on feed and silkworm cocoons grown on mulberry leaves. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Potassium persulfate (analytical grade, Shanghai McLean Biochemical Technology Co., Ltd.), deionized water, anhydrous ethanol (Hangzhou Gaojing Fine Chemical Co., Ltd.), disodium hydrogen phosphate dihydrate, sodium dihydrogen phosphate, and 2,2-azino-bis(3-ethyl-benzothiazole-6-sulfonic acid) diammonium salt (ABTS) used in the present invention are all analytical grade (Aladdin Reagent Co., Ltd.).

[0021] Example 1

[0022] The samples to be tested are mulberry leaf cocoon silk from any of Guangxi, Yunnan and Sichuan, and the feed cocoon silk is produced by the Babe Group. The steps of identifying feed cocoon silk by the method of the present invention are as follows:

[0023] S1, prepare 7mmol / L ABTS solution and 2.45mmol / L potassium persulfate solution with deionized water respectively, and mix them in a volume ratio of 1:1. The resulting mixed solution is stored in the dark at room temperature for 14±2h to obtain ABTS + Storage solution;

[0024] S2, prepare a 0.1 mol / L phosphate buffer solution with a pH of 7.4 using disodium hydrogen phosphate dihydrate and sodium dihydrogen phosphate. + Dilute the stock solution 45 ± 5 times so that its absorbance at 733 nm is 0.700 ± 0.025 to obtain ABTS + ·Assay solution;

[0025] S3, add 1 mL of anhydrous ethanol to 60 mg of the sample to be tested, and then add 20 mL of ABTS in the dark. +· The test solution was sealed and ultrasonically vibrated for 30 seconds, stored in a constant temperature water bath at 30°C in the dark for 6 minutes, taken out and filtered, and the supernatant was retained;

[0026] S4, calibrate to zero with deionized water, measure the absorbance of the supernatant at 734nm, measure each sample 3 times, take the average value and record it as A 样品 ;

[0027] S5, the blank control group used the same treatment conditions and experimental methods, by adding 20mL ABTS to 1mL anhydrous ethanol + The mixed solution without silkworm cocoons was obtained by measuring the absorbance at 734 nm and recorded as A 空白 ;

[0028] S6, calculate the sample ABTS according to the following formula + Clearance rate,

[0029] ABTS + · Clearance rate / % = (A 空白 -A 样品 ) / A 空白 ×100 (1)

[0030] Since ABTS was not added to the sample + ·The absorbance of the measurement solution gradually decreases, so a solvent blank is used in each measurement.

[0031] from Figure 1 The test results show that the antioxidant properties of mulberry leaf cocoon silk are significantly better than those of feed cocoon silk, and there are obvious differences between the two components. The identification method of the present invention is superior to the conventional detection method, has high accuracy and strong practicality. The identification method of the present invention improves the accuracy of cocoon silk quality identification and enhances the reliability of identification, which is greatly beneficial to the standardization of raw silk market transactions and the control of raw silk product quality.

[0032] Example 2

[0033] The samples to be tested are mulberry leaf cocoon silk from any of Guangxi, Yunnan and Sichuan, and the feed cocoon silk is produced by Yashilin Changsha (International). The steps of identifying feed cocoon silk by the method of the present invention are as follows:

[0034] S1, prepare 7mmol / L ABTS solution and 2.45mmol / L potassium persulfate solution with deionized water respectively, and mix them in a volume ratio of 1:1. The resulting mixed solution is stored in the dark at room temperature for 14±2h to obtain ABTS + Storage solution;

[0035] S2, prepare a 0.1 mol / L phosphate buffer solution with a pH of 7.4 using disodium hydrogen phosphate dihydrate and sodium dihydrogen phosphate. + Dilute the stock solution 45 ± 5 times so that its absorbance at 733 nm is 0.700 ± 0.025 to obtain ABTS + ·Assay solution;

[0036] S3, add 1 mL of anhydrous ethanol to 60 mg of the sample to be tested, and then add 20 mL of ABTS in the dark. +· The test solution was sealed and ultrasonically vibrated for 30 seconds, stored in a constant temperature water bath at 30°C in the dark for 6 minutes, taken out and filtered, and the supernatant was retained;

[0037] S4, calibrate to zero with deionized water, measure the absorbance of the supernatant at 734nm, measure each sample 3 times, take the average value and record it as A 样品 ;

[0038] S5, the blank control group used the same treatment conditions and experimental methods, by adding 20mL ABTS to 1mL anhydrous ethanol + The mixed solution without silkworm cocoons was obtained by measuring the absorbance at 734 nm and recorded as A 空白 ;

[0039] S6, calculate the sample ABTS according to the following formula + Clearance rate,

[0040] ABTS + · Clearance rate / % = (A 空白 -A 样品 ) / A 空白 ×100 (1)

[0041] Since ABTS was not added to the sample + ·The absorbance of the measurement solution gradually decreases, so a solvent blank is used in each measurement.

[0042] From the test results, it can be concluded that the antioxidant value of mulberry leaf cocoon silk is higher than that of feed cocoon silk, and there is a significant difference between the two components. From the tests in Example 1 and Example 2, it can be seen that the mulberry leaf cocoon silk and the feed cocoon silk are different in origin and the feed cocoon silk can also be quickly identified. The identification method of the present invention is superior to the conventional detection method, with high accuracy and strong practicality.

[0043] The above are only preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be based on the scope defined by the claims. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A method for identifying silkworm cocoons grown with feed, characterized in that: The invention comprises cocoon silks grown on feed, wherein the cocoon silks grown on feed are spun by silkworms of all ages that have eaten feed, and the content of polyphenol antioxidants in the cocoon silks grown on feed is lower than that in the cocoon silks grown on mulberry leaves.

2. The method for identifying silkworm cocoons raised with feed according to claim 1, characterized in that: The identification method is to detect the scavenging performance of the sample to be tested on ABTS free radicals to reflect the antioxidant performance of the sample to be tested, and to determine whether the sample to be tested is mulberry leaf silkworm cocoon silk or feed silkworm cocoon silk according to the scavenging performance of ABTS free radicals.

3. The method for identifying silkworm cocoons raised with feed according to claim 2, characterized in that: The content of the polyphenol antioxidant substances is detected by ABTS free radical scavenging ability, and the detection steps of the ABTS free radical scavenging ability are as follows: S1, prepare 7mmol / L ABTS solution and 2.45mmol / L potassium persulfate solution with deionized water respectively, and mix them in a volume ratio of 1:

1. The resulting mixed solution is stored in the dark at room temperature for 14±2h to obtain ABTS + Storage solution; S2, prepare a 0.1 mol / L phosphate buffer solution with a pH of 7.4 using disodium hydrogen phosphate dihydrate and sodium dihydrogen phosphate. + Dilute the stock solution 45 ± 5 times so that its absorbance at 733 nm is 0.700 ± 0.025 to obtain ABTS + ·Assay solution; S3, add 1 mL of anhydrous ethanol to 60 mg of the sample to be tested, and then add 20 mL of ABTS in the dark. +· The test solution was sealed and ultrasonically vibrated for 30 seconds, stored in a constant temperature water bath at 30°C in the dark for 6 minutes, taken out and filtered, and the supernatant was retained; S4, calibrate to zero with deionized water, measure the absorbance of the supernatant at 734nm, measure each sample 3 times, take the average value and record it as A 样品 ; S5, the blank control group used the same treatment conditions and experimental methods, by adding 20mL ABTS to 1mL anhydrous ethanol + The mixed solution without silkworm cocoons was obtained by measuring the absorbance at 734 nm and recorded as A 空白 ; S6, calculate the sample ABTS according to the following formula + Clearance rate. ABTS + · Clearance rate / % = (A 空白 -A 样品 ) / A 空白 ×100 (1) 。 4. The method for identifying silkworm cocoons raised with feed according to claim 3, characterized in that: ABTS of the sample to be tested + When the removal rate is within the range of 45-58%, the sample is judged to be feed silkworm cocoon silk; Otherwise, the sample to be tested is determined to be mulberry leaf-grown cocoon silk.

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