Summary of the invention
To be solved by this invention is the technical matters that current Cordyceps sinensis herb is difficult to minute true and false.
The technical scheme that the present invention solves the problems of the technologies described above is to provide a kind of method of quick and precisely differentiating Cordyceps sinensis herb, comprises the following steps:
A, Cordyceps sinensis herb standard spectrum are drawn: the standard Cordyceps sinensis herb sample in a plurality of different places of production is pressed into respectively thin slice and carries out transmission test, and the averaged spectrum of all samples is Cordyceps sinensis herb standard spectrum;
The collection of b, the indispensable characteristic peak of Cordyceps sinensis herb infrared spectrum and the common characteristic peak of Cordyceps sinensis herb infrared spectrum;
The diffuse reflectance infrared spectroscopy peak comparison of c, tested Cordyceps sinensis herb sample and the comparison of infrared spectrum similarity: in the infrared spectrum of sample, comprise the indispensable characteristic peak of whole Cordyceps sinensis herb infrared spectrums and the more than 60% of the common characteristic peak of Cordyceps sinensis herb infrared spectrum, and the level of significance between sample spectrum and Cordyceps sinensis herb standard spectrum is that the related coefficient lower threshold of 0.01 o'clock is 0.95, and this sample is genuine piece Cordyceps sinensis herb.
Wherein, in the step a of the Infrared spectroscopy authentication method of above-mentioned Cordyceps sinensis herb, described Cordyceps sinensis herb sample is to be selected from Yushu district, Qinghai state, national main producing region, Forage Land In Guoluo Prefecture, state, Hainan and Tibet, Sichuan and area, 6, Gansu, and each provenance selection is not less than 8 uniform samples.
Wherein, in the step a of the Infrared spectroscopy authentication method of above-mentioned Cordyceps sinensis herb, described Cordyceps sinensis herb sample is by the natural drying rear pulverizing of the polypide part of Cordyceps sinensis, gets fine powder after 200 mesh sieves for examination of infrared spectrum.
Wherein, in the step a of said method, the standard Cordyceps sinensis herb sample in a plurality of different places of production is pressed into respectively thin slice and carries out transmission when test, carries out under the same conditions compressing tablet test, as spectral background with the pure potassium bromide that does not add any sample.
Wherein, in the step a of said method, the transmitance maximal value of every sample infrared spectrum and minimum value differ and should be not less than 60%.
Wherein, in the step a of said method, each sample replication 3~5 times, gets its averaged spectrum as the spectrum of this sample.
Wherein, in the step a of said method, Infrared spectrum scanning scope is 4000~400cm
-1, spectral resolution is 4cm
-1, every spectrum cumulative scan 16 times or 32 times, deducts in real time carbon dioxide and water vapor and disturbs.
Wherein, in the step b of said method, the indispensable characteristic peak of described Cordyceps sinensis herb infrared spectrum refers to the infrared spectrum absorpting peak position of comparison all samples, the indispensable characteristic peak using the absorption peak all occurring in all samples as Cordyceps sinensis herb infrared spectrum.The indispensable characteristic peak of described Cordyceps sinensis herb infrared spectrum is as shown in table 1:
The indispensable characteristic peak of table 1 Cordyceps sinensis herb infrared spectrum
Peak numbering |
Peak position mean value (cm
-1)
|
Deviation (cm in peak position under 99% degree of confidence
-1)
|
A01 |
3292 |
6.2 |
A02 |
2926 |
2.6 |
A03 |
1657 |
3.6 |
A04 |
1547 |
4.1 |
A05 |
1457 |
7.2 |
A06 |
1083 |
2.6 |
A07 |
1024 |
3.4 |
A08 |
930 |
2.1 |
A09 |
888 |
4.1 |
A10 |
626 |
6.5 |
Wherein, in the step b of said method, the described common characteristic peak of Cordyceps sinensis herb infrared spectrum refers in the infrared spectrum absorpting peak of all samples, except indispensable characteristic peak, probability of occurrence is not less than to 80% absorption peak, as the common characteristic peak of Cordyceps sinensis herb infrared spectrum.The common characteristic peak of described Cordyceps sinensis herb infrared spectrum is as shown in table 2:
The common characteristic peak of table 2 Cordyceps sinensis herb infrared spectrum
Peak numbering |
Peak position mean value (cm
-1)
|
Deviation (cm in peak position under 99% degree of confidence
-1)
|
B01 |
2854 |
1.3 |
B02 |
1745 |
3.9 |
B03 |
1378 |
1.3 |
B04 |
1249 |
5.2 |
B05 |
1202 |
2.6 |
B06 |
1152 |
4.9 |
B07 |
574 |
4.9 |
B08 |
528 |
8.5 |
B09 |
416 |
4.4 |
Wherein, in the step c of said method, described related coefficient is calculated by following formula:
(formula 1)
In formula 1, R
ijrepresent the related coefficient of infrared spectrum i and infrared spectrum j, x
ikand x
jkrepresentative sample i and sample j are at the absorbance at wave number k place respectively.
The present invention uses AssureID software to calculate 1800~800cm
-1in scope, the related coefficient of each sample infrared spectrum and standard spectrum, adds up the distributed area of the related coefficient of each sample infrared spectrum and standard spectrum, determines that level of significance is the related coefficient lower threshold of 0.01 o'clock.
The present invention chooses the typical sample in the different places of production, national main producing region, has determined the common characteristic peak of Cordyceps sinensis herb, has set up Cordyceps sinensis herb standard infrared spectrum, and has determined the correlation coefficient threshold of genuine piece and standard spectrum.Integrated using diffuse reflectance infrared spectroscopy peak differential method and similarity differential method, can be objective, accurate, easy, rapidly Cordyceps sinensis herb is differentiated.
In recent years, infrared spectrum extensively and the true and false that is successfully used to various Chinese crude drugs differentiate, have objective quantification, result accurate, easy and simple to handle, test the plurality of advantages such as rapid, with low cost.The present invention utilizes infra-red sepectrometry to set up the finger-print of Cordyceps sinensis herb, for the Cordyceps sinensis true and false, differentiates objective, accurate, easy, analytical approach is fast provided.
Embodiment
The Infrared spectroscopy authentication method of Cordyceps sinensis herb provided by the invention, comprises the following steps:
A, Cordyceps sinensis herb standard spectrum draw: choose 15 parts of Yushu district, Qinghai states |, the Cordyceps sinensis herb sample in 15 parts of Forage Land In Guoluo Prefectures, 15 parts of Hai Nanzhou, 15 parts of Tibet, 15 parts of Sichuan and 8 parts of Gansu, the uniform sample of each provenance selection, adopt pellet technique to carry out transmission test, the averaged spectrum of all samples is Cordyceps sinensis herb standard spectrum.
The mid-infrared spectral data processing of the present invention and Spectrum (v6) and AssureID (v4) software of analyzing use U.S. PerkinElmer company.The sample infrared spectrum initially recording is transmitance figure, comprises the spectrum baseline wander that scattering causes, the spectral intensity difference error factors that amount of samples causes, and need to be eliminated by spectrogram pre-service measures such as baseline correction, normalization.Therefore, use successively the ordinate of Spectrum software to change (transmitance is converted to absorbance), automatic baseline correction, normalization (in full spectral range, high absorbance is 1, and minimum absorbance is 0) function is processed original transmitance spectrogram.The spectrum computing function of use Spectrum software obtains the averaged spectrum of 3~5 replication spectrum of each sample, as the spectrum of this sample.According to the infrared spectrum of all samples, can calculate its averaged spectrum, as the standard spectrum of Cordyceps sinensis herb.
The collection of b, the indispensable characteristic peak of Cordyceps sinensis herb infrared spectrum and the common characteristic peak of Cordyceps sinensis herb infrared spectrum.
Use Spectrum software to read each sample diffuse reflectance infrared spectroscopy peak position, peak intensity threshold value is the strength difference minimum value of the adjacent peak valley of 0.01A(and both sides), use maximum value process (Interpolated Peak) is determined in peak position.Use the characteristic peak positions of Excel or other software analysis all samples.
The diffuse reflectance infrared spectroscopy peak comparison of c, tested Cordyceps sinensis herb sample and the comparison of infrared spectrum similarity: in the infrared spectrum of sample, comprise the indispensable characteristic peak of whole Cordyceps sinensis herb infrared spectrums and the more than 60% of the common characteristic peak of Cordyceps sinensis herb infrared spectrum, and the level of significance between sample spectrum and Cordyceps sinensis herb standard spectrum is that the related coefficient lower threshold of 0.01 o'clock is 0.95, and this sample is genuine piece Cordyceps sinensis herb.
Wherein, in the step a of the Infrared spectroscopy authentication method of above-mentioned Cordyceps sinensis herb, described Cordyceps sinensis herb sample is by the natural drying rear pulverizing of the polypide part of Cordyceps sinensis, gets fine powder after 200 mesh sieves for examination of infrared spectrum.
Wherein, in the step a of said method, the standard Cordyceps sinensis herb sample in a plurality of different places of production is pressed into respectively thin slice and carries out transmission when test, carries out under the same conditions compressing tablet test, as spectral background with the pure potassium bromide that does not add any sample.
Wherein, in the step a of said method, the transmitance maximal value of every sample infrared spectrum and minimum value differ and should be not less than 60%.
Wherein, in the step a of said method, each sample replication 3~5 times, gets its averaged spectrum as the spectrum of this sample.
Wherein, in the step a of said method, Infrared spectrum scanning scope is 4000~400cm
-1, spectral resolution is 4cm
-1, every spectrum cumulative scan 16 times or 32 times, deducts in real time carbon dioxide and water vapor and disturbs.
Wherein, in the step b of said method, the indispensable characteristic peak of described Cordyceps sinensis herb infrared spectrum refers to the infrared spectrum absorpting peak position of comparison all samples, the indispensable characteristic peak using the absorption peak all occurring in all samples as Cordyceps sinensis herb infrared spectrum.
Further, in the step b of said method, the indispensable characteristic peak of Cordyceps sinensis herb infrared spectrum has 10.
Wherein, in the step b of said method, the described common characteristic peak of Cordyceps sinensis herb infrared spectrum refers in the infrared spectrum absorpting peak of all samples, except indispensable characteristic peak, probability of occurrence is not less than to 80% absorption peak, as the common characteristic peak of Cordyceps sinensis herb infrared spectrum.
Further, in the step b of said method, the common characteristic peak of Cordyceps sinensis herb infrared spectrum has 9.
Wherein, in the step c of said method, described related coefficient is calculated by following formula:
(formula 1)
In formula 1, R
ijrepresent the related coefficient of infrared spectrum i and infrared spectrum j, x
ikand x
jkrepresentative sample i and sample j are at the absorbance at wave number k place respectively.
In step b, the indispensable characteristic peak of Cordyceps sinensis herb infrared spectrum is in Table 3.
The indispensable characteristic peak of infrared spectrum of table 3 Cordyceps sinensis herb
In step b, the common characteristic peak of Cordyceps sinensis herb infrared spectrum is in Table 4.
The common characteristic peak of infrared spectrum of table 4 Cordyceps sinensis herb
The present invention uses AssureID software to calculate 1800~800 cm
-1in scope, the related coefficient of each sample infrared spectrum and standard spectrum, adds up the distributed area of the related coefficient of each sample infrared spectrum and standard spectrum, determines that level of significance is the related coefficient lower threshold of 0.01 o'clock.
Characteristic peak is differentiated the position of only having considered common characteristic peak, does not relate to intensity and the shape information at common characteristic peak, does not also relate to the information of other absorption peaks outside the common characteristic peak that the frequency of occurrences is higher, and needs characteristic peak number relatively more.Therefore, except above-mentioned according to common characteristic peak, differentiate, also need to differentiate according to infrared spectrum similarity, namely with correlation coefficient process, the global similarity degree between sample spectra and standard spectrum is carried out to single quantification comparison.
In the present invention, standard spectrum used is the averaging spectrum of all samples spectrum, because position and the intensity change of some absorption peaks in different samples are larger, when carrying out the discriminating of infrared spectrum similarity, has only chosen 1800~800 cm
-1spectrum in scope, this district inclusion the topmost characteristic peak of sample, and spectrum change is subject to ectocine less.Related coefficient between sample spectra and Cordyceps sinensis herb standard spectrum is carried out to statistical study, determine that level of significance is that the related coefficient lower threshold of 0.01 o'clock is 0.95.That is to say, 99% in the situation that, if testing sample is genuine piece Cordyceps sinensis herb, the related coefficient of its infrared spectrum and standard spectrum is not less than 0.95.
Embodiment 1 Cordyceps sinensis herb standard spectrum drafting, the indispensable characteristic peak of Cordyceps sinensis herb infrared spectrum and the collection of the common characteristic peak of Cordyceps sinensis herb infrared spectrum and determining of related coefficient lower threshold
1) sample source and processing
Choose 15 parts of Yushu district, Qinghai states |, the Cordyceps sinensis sample in 15 parts of Forage Land In Guoluo Prefectures, 15 parts of Hai Nanzhou, 15 parts of Tibet, 15 parts of Sichuan and 8 parts of Gansu, the uniform sample of each provenance selection.
Sample preparation is with reference to Pharmacopoeia of People's Republic of China relevant regulations, by the natural drying rear pulverizing of sample polypide part, gets fine powder after 200 mesh sieves for examination of infrared spectrum.
2) infrared spectrum instrument
In the present invention, U.S. PerkinElmer(platinum Ai Ermo is all used in all samples test) the Spectrum One Fourier transformation infrared spectrometer of company.
Sample test parameter: spectral scan scope 4000~400cm
-1, spectral resolution 4cm
-1, every spectrum cumulative scan 16 times or 32 times, deducts in real time carbon dioxide and water vapor and disturbs.
3) examination of infrared spectrum method
Sample test adopts potassium bromide (KBr) pressed disc method.Get 1~2 milligram of sample powder and 100 milligrams of spectroscopic pure potassium bromide broken grains ground and mixed in agate mortar is even, with sheeter, mixed-powder is pressed into thin rounded flakes, put into sample holder of Infrared spectrometer and carry out transmission test.With the pure potassium bromide that does not add any sample, carry out under the same conditions compressing tablet test, as spectral background.
The transmitance maximal value of every sample infrared spectrum and minimum value differ and should be not less than 60%.
Each sample replication 3~5 times, gets its averaged spectrum as the spectrum of this sample.
4) ir data is processed
This is studied mid-infrared spectral data processing and analyzes Spectrum (v6) and AssureID (v4) software that uses U.S. PerkinElmer company.
The sample infrared spectrum initially recording is transmitance figure, comprises the spectrum baseline wander that scattering causes, the spectral intensity difference error factors that amount of samples causes, and need to be eliminated by spectrogram pre-service measures such as baseline correction, normalization.Therefore, use successively the ordinate of Spectrum software to change (transmitance is converted to absorbance), automatic baseline correction, normalization (in full spectral range, high absorbance is 1, and minimum absorbance is 0) function is processed original transmitance spectrogram.
5) standard spectrum is drawn
The spectrum computing function of use Spectrum software obtains the averaged spectrum of 3~5 replication spectrum of each sample, as the spectrum of this sample.According to the infrared spectrum of all 30 samples, can calculate its averaged spectrum, as the standard spectrum of Cordyceps sinensis herb.
6) collection of the indispensable characteristic peak of Cordyceps sinensis herb infrared spectrum and the common characteristic peak of Cordyceps sinensis herb infrared spectrum
Use Spectrum software to read each sample diffuse reflectance infrared spectroscopy peak position in embodiment 1, peak intensity threshold value is 0.01 absorbance (with the strength difference minimum value of the adjacent peak valley in both sides), and use maximum value process (Interpolated Peak) is determined in peak position.Use the characteristic peak positions of Excel or all 30 samples of other software analysis.
Relatively the diffuse reflectance infrared spectroscopy peak position of all samples, has 14 absorption peaks all to occur in all samples, can be used as the indispensable characteristic peak of genuine piece Cordyceps sinensis herb infrared spectrum, as shown in table 1.
In the diffuse reflectance infrared spectroscopy peak of all samples, have 9 absorption peak probabilities of occurrence to be not less than in 24~29 sample infrared spectrums in 80%(30 sample and occur), can be used as the common characteristic peak of genuine piece Cordyceps sinensis herb infrared spectrum, as shown in table 2.
7) related coefficient lower threshold determines
Use AssureID software to calculate 1800~800cm
-1the related coefficient of each sample infrared spectrum and standard spectrum in scope, formula is as follows:
(formula 1)
In formula, R
ijrepresent the related coefficient of infrared spectrum i and infrared spectrum j, x
ikand x
jkdistinguish representative sample i and sample j at the absorbance at wave number k place,
Add up the distributed area of the related coefficient of each sample infrared spectrum and averaged spectrum, determine that level of significance is the related coefficient lower threshold of 0.01 o'clock.
Related coefficient between sample spectra and Cordyceps sinensis herb standard spectrum is carried out to statistical study, determine that level of significance is that the related coefficient lower threshold of 0.01 o'clock is 0.95.That is to say, 99% in the situation that, if testing sample is genuine piece Cordyceps sinensis polypide herb, the related coefficient of its infrared spectrum and standard spectrum is not less than 0.95.
Embodiment 2 experiment of discerning the false from the genuine
1) sample source and processing
Commercially available Cordyceps gunnii (Berk.) Berk, numbering is respectively G1, G2, G3, G4.
Sample preparation is with reference to Pharmacopoeia of People's Republic of China relevant regulations, by the natural drying rear pulverizing of sample herb part, gets fine powder after 200 mesh sieves for examination of infrared spectrum.
2) infrared spectrum instrument
The Spectrum One Fourier transformation infrared spectrometer of U.S. PerkinElmer company is all used in all samples test.
Sample test parameter: spectral scan scope 4000~400cm
-1, spectral resolution 4cm
-1, every spectrum cumulative scan 16 times, deducts in real time carbon dioxide and water vapor and disturbs.
3) examination of infrared spectrum method
Sample test adopts potassium bromide (KBr) pressed disc method.Get 1~2 milligram of sample powder and 100 milligrams of spectroscopic pure potassium bromide broken grains ground and mixed in agate mortar is even, with sheeter, mixed-powder is pressed into thin rounded flakes, put into sample holder of Infrared spectrometer and carry out transmission test.With the pure potassium bromide that does not add any sample, carry out under the same conditions compressing tablet test, as spectral background.
The transmitance maximal value of every sample infrared spectrum and minimum value differ and should be not less than 60%.
Each sample replication 3~5 times, gets its averaged spectrum as the spectrum of this sample.
4) ir data is processed
This is studied mid-infrared spectral data processing and analyzes Spectrum (v6) software that uses U.S. PerkinElmer company.
The sample infrared spectrum initially recording is transmitance figure, comprises the spectrum baseline wander that scattering causes, the spectral intensity difference error factors that amount of samples causes, and need to be eliminated by spectrogram pre-service measures such as baseline correction, normalization.Therefore, use successively the ordinate of Spectrum software to change (transmitance is converted to absorbance), automatic baseline correction, normalization (in full spectral range, high absorbance is 1, and minimum absorbance is 0) function is processed original transmitance spectrogram.
5) Cordyceps gunnii (Berk.) Berk herb diffuse reflectance infrared spectroscopy peak gather, with the comparison of Cordyceps sinensis herb standard spectrum characteristic peak
Use Spectrum software to read each sample diffuse reflectance infrared spectroscopy peak position in embodiment 2, peak intensity threshold value is 0.01 absorbance (with the strength difference minimum value of the adjacent peak valley in both sides), use maximum value process (Interpolated Peak) is determined in peak position, and result is as shown in table 5.
Table 5 Cordyceps gunnii (Berk.) Berk herb diffuse reflectance infrared spectroscopy peak
6) Cordyceps gunnii (Berk.) Berk and the comparison of Cordyceps sinensis herb standard spectrum characteristic peak
Table 6 Cordyceps gunnii (Berk.) Berk and the peak comparison of Cordyceps sinensis herb diffuse reflectance infrared spectroscopy
Table 6 is depicted as in Cordyceps gunnii (Berk.) Berk herb diffuse reflectance infrared spectroscopy peak the part of conform to Cordyceps sinensis herb standard spectrum characteristic peak (in table 1 and table 2 characteristic peak 99% fiducial interval).As can be seen from Table 6, all there is not the indispensable characteristic peak of whole Cordyceps sinensis herbs in four Cordyceps gunnii (Berk.) Berk herbs, illustrates that method of the present invention can effectively carry out true and false discriminating.