The use of Chromatography and Mass Spectrometry to assess … · 2016. 9. 4. · The use of...
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The use of Chromatography and Mass Spectrometry to assess quality and authenticity of naturally charged foods and dietary supplements Part 1: Herbal Commodities Given by: John Lee Global Food Market Manager at Agilent Technologies
Transcript of The use of Chromatography and Mass Spectrometry to assess … · 2016. 9. 4. · The use of...
The use of Chromatography and Mass Spectrometry to assess quality and authenticity of naturally charged foods and dietary supplements
Part 1: Herbal Commodities
Given by: John LeeGlobal Food Market Manager at Agilent Technologies
The use of Chromatography and Mass Spectrometry to assess quality and authenticity of naturally charged foods and dietary supplements………..(20 minutes)• Key active compounds are valued and should be tested
• Liquid chromatography is an important tool in herbal commodities
• Assessment of authenticity and freshness is also increasingly important.• Analysing the fingerprint of the whole sample is often also required
- Mass spec is an important tool for holistic authenticity assessment.
Consideration of oil based
commodities such as olive oil and fish oil will
be addressed in a separate
presentation
Active Compound assessment in Herbals
Extracts from herbal commodities are
complexNeed for high
selectivity Gradient LC is a
common tool
Reference methods can have long run
times
Agilent 1290 UHPLCZorbax Sub 2 micron
Zorbax Poroshell
Faster run timesNo compromise
Increased resolution
New levels of flow precision
and mixing
Presenter
Presentation Notes
Gradient elution with LC is of particular help in the complex matrices of Botanicals. The seeds of the Mediterranean Milk Thistle contain active components called silymarins that our conferring this anti-inflamatory/anti oxidant effects. Milk Thistle has been used for over 2000 years to treat liver and bladder problems protecting these organs from toxins and encouraging new growth. Here we see a their analysis using 1290 UHPLC and UV detection using a method with a total run time of 15 minutes. This compares to a reference methods of 50 minutes but selectivity here is un compromised with key compounds seperated from other matrix components and separation between critical pairs like silybinin A and B maintained. Ginkgo Biloba extract improves memory, treats depression, blood circulation. But regukations in US state that active compounds need to be controlled to around 6%. Here we see an analysis (this time with the Agilent 385 an evaporative light scattering detector) which has a total run time less than 13 minutes which as before is nearly 4 times faster that the reference method. Once gain this is possible due to the efficiencies of UHPLC technology which delivers the excellent selectivity to matrix and to critical pairs of compounds that must be all be quantified. USP methods offer well characterized methods for botanical activity but are slow & with high solvent consumption. New developments in STM and porous shell technologies require a new generation of LC systems which can realize the full potential of these columns to reduce run times whilst improving resolution of active compounds from background peaks. Pumps must have lower dead volumes and more stable flow delivery to deliver super-fast gradient elution that will start instantaneously and resets promptly for the next sample. Need for a flexible choice of new LC detectors with the higher frequency detection necessary for high resolution chromatography increasingly important tool because
Active Compound assessment in Herbals
Application Note Link
Data courtesy of
Presenter
Presentation Notes
Gradient elution with LC is of particular help in the complex matrices of Botanicals. The seeds of the Mediterranean Milk Thistle contain active components called silymarins that our conferring this anti-inflamatory/anti oxidant effects. Milk Thistle has been used for over 2000 years to treat liver and bladder problems protecting these organs from toxins and encouraging new growth. Here we see a their analysis using 1290 UHPLC and UV detection using a method with a total run time of 15 minutes. This compares to a reference methods of 50 minutes but selectivity here is un compromised with key compounds seperated from other matrix components and separation between critical pairs like silybinin A and B maintained. Ginkgo Biloba extract improves memory, treats depression, blood circulation. But regukations in US state that active compounds need to be controlled to around 6%. Here we see an analysis (this time with the Agilent 385 an evaporative light scattering detector) which has a total run time less than 13 minutes which as before is nearly 4 times faster that the reference method. Once gain this is possible due to the efficiencies of UHPLC technology which delivers the excellent selectivity to matrix and to critical pairs of compounds that must be all be quantified. USP methods offer well characterized methods for botanical activity but are slow & with high solvent consumption. New developments in STM and porous shell technologies require a new generation of LC systems which can realize the full potential of these columns to reduce run times whilst improving resolution of active compounds from background peaks. Pumps must have lower dead volumes and more stable flow delivery to deliver super-fast gradient elution that will start instantaneously and resets promptly for the next sample. Need for a flexible choice of new LC detectors with the higher frequency detection necessary for high resolution chromatography increasingly important tool because
Active Compound assessment in Herbals
Application Note Link Application Note Link
Data courtesy of
Presenter
Presentation Notes
Gradient elution with LC is of particular help in the complex matrices of Botanicals. The seeds of the Mediterranean Milk Thistle contain active components called silymarins that our conferring this anti-inflamatory/anti oxidant effects. Milk Thistle has been used for over 2000 years to treat liver and bladder problems protecting these organs from toxins and encouraging new growth. Here we see a their analysis using 1290 UHPLC and UV detection using a method with a total run time of 15 minutes. This compares to a reference methods of 50 minutes but selectivity here is un compromised with key compounds seperated from other matrix components and separation between critical pairs like silybinin A and B maintained. Ginkgo Biloba extract improves memory, treats depression, blood circulation. But regukations in US state that active compounds need to be controlled to around 6%. Here we see an analysis (this time with the Agilent 385 an evaporative light scattering detector) which has a total run time less than 13 minutes which as before is nearly 4 times faster that the reference method. Once gain this is possible due to the efficiencies of UHPLC technology which delivers the excellent selectivity to matrix and to critical pairs of compounds that must be all be quantified. USP methods offer well characterized methods for botanical activity but are slow & with high solvent consumption. New developments in STM and porous shell technologies require a new generation of LC systems which can realize the full potential of these columns to reduce run times whilst improving resolution of active compounds from background peaks. Pumps must have lower dead volumes and more stable flow delivery to deliver super-fast gradient elution that will start instantaneously and resets promptly for the next sample. Need for a flexible choice of new LC detectors with the higher frequency detection necessary for high resolution chromatography increasingly important tool because
Active Compound assessment of a spice
Application Note Link
Data courtesy of
Presenter
Presentation Notes
Gradient elution with LC is of particular help in the complex matrices of Botanicals. The seeds of the Mediterranean Milk Thistle has been used for over 2000 years to treat liver and bladder problems protecting these organs from toxins and encouraging new growth Fast analysis of silymarins that our conferring this anti-inflamatory/anti oxidant effect Ginkgo Biloba extract improves memory, treats depression, blood circulation. But regulation requires that active compounds need to be controlled to around 6%. USP methods offer well characterized methods for botanical activity but are slow & with high solvent consumption. New developments in STM and porous shell technologies require a new generation of LC systems which can realize the full potential of these columns to reduce run times whilst improving resolution of active compounds from background peaks. Pumps must have lower dead volumes and more stable flow delivery to deliver super-fast gradient elution that will start instantaneously and resets promptly for the next sample. Need for a flexible choice of new LC detectors with the higher frequency detection necessary for high resolution chromatography increasingly important tool because Turmeric comes from Curcuma Longa plant and contains curcumin, Arthritis, digestive problems, urinary issues, skin conditions, low energy, even alzheimers and diabetes
Active Compound assessment by Gradient UHPLC
Mass Profiler Professional
DeconvolutionUsing Molecular feature extraction
Application Note LinkJournal Publication Link
Presenter
Presentation Notes
Here is another example of gradient UHPLC in action which has been validated for quantification monacolins. In this new research the team…..were able to show how in dietary supplements based on red rice the ratios of monacolins differed significantly from sample to sample. This discovery clearly has implications both for efficacy of such tablets and as a tool for assessing identity of different products or the red rice used to make them. Indeed the team also discovered significant variation in shipments of red rice commodity they also tested with this method. However this variation was more worrying since in many case monocolins were infact totally absent. Whether red rice is destined for a dietary supplements or other food products, this is the sort of discovery which suggest that a more sophisticated authenticity test might be helpful for such a commodity particularly given that the rice is often reduced to a powder before shipment. With this in mind the team added a Mass spectrometer to their system to help see more. Through the added selectivity of mass differentiation the MS was able to see many more peaks because it was able to deconvolute peaks within peaks. These were assesed with chemometrics and this proved to allow classification of different classes of red rice commodity including an association with non monocolin containing raw materials. The team were even able to identify many of these marker compounds through their accurate mass and accurate mass MS/MS fragments. Infact with so much complexity in such a sample the MS was also considered an important supporting tool for the quantitation itself since it was able to verify peaks being quantified with the UV. including 12monacolins, 13 pigments and citrinin The method revealed Citrinin (a mycotoxin) was detected in six of these raw materials at levels from 10 to 80 μg/g Levels of quantified monocolins in raw materials were highly variable and absent in many cases. MS: identification of the right peak. Worth having with the UV? Quant reveals that recommended dose of these active compounds per tablet or serving is difficult to predict. There is some variation between actives. However MS reveals that the certain raw materials are naturally low in those anyway. , citrinin and sudan redG) authentic samples monacolin K monacolin K acid 1-3mg/g Citrinin not detected raw material varied widely from none to very high 24.3 mg/g Of the 31 RYRraw materials analyzed, only 21 contained monacolins Citrinin (a mycotoxin) was detected in six of these samples at levels from 10 to 80 μg/g DS monacolin K from 0.03 to 2.62 but not citrinin ratios of monacolins that differed significantly from the authentic samples Those raw materials with no monocolin later showed they could be modelled according to their pigment Again The method described herein is highly sensitive and suitable for qualitative analysis of wide range of compounds including 12monacolins, 13 pigments and citrinin.
Saponin in Yams: UHPLC QTOF……..
• QTOF MS detection • More selectivity
• opportunity to simplify sample prep.• opportunity to verify results.
• Database can be created to streamline workflow• active searching increases sensitivity. • active searching means knowing the right ions.
• MSMS Library• further verification
PCDLPersonal
Compound Database
and Library
Mass Profiler Professional
Find my formula searchingMSMS spectral verification
Application Note LinkJournal Publication Link
Presenter
Presentation Notes
In this example the UV detector has been dispensed with entirely because the research group in question considered previous UV methods not to be sensitive enough for measurement in the appropriate range for Saponins. Indeed this selectivity allowed this group to avoid the long and laborious purification of these compounds from crude extracts that other methods. This selectivity is driven by the a library driven deconvolution & verification strategy that is possible with a QTOF. Agilent use a tool called PCDL Manager which allows spectra to be curated in a library Entries made by the group involved buying standards and injecting them. But others where not available as standards and were discovered simply by looking for the characteristic fragmentation patterns of steroidal saponins in the data. And as with the previous example the complete data that full scan mass spec like a QTOF provides was not wasted. This data was assesed with chemometrics and this proved to allow differentiation of two Yam species and various different dietary supplements. The diversity of saponins that can be found in certain species of Yams allows the same analysis to also be used to differentiate between species through use of Chemometric modelling and so to facilitate identification and quality control of those species prized for their medicinal activity. This control is of particular importance given that many of these yams are also a key feed for the ever growing dietary supplements market.
Identity Fingerprinting using GC Single Quad MS
Deconvolution Mass Profiler Professional
80 identified compounds used in model
Application Note LinkJournal Publication Link
Presenter
Presentation Notes
Another full scan technique which can allow powerful chemometric based differentiation is the GCMSD which was used by the team from Missisipi…….. At this point in the presentation we have now moved entirely away from thinking about active compounds and simply to focus on differentiating commodioties. That’s an important question for Chamomile for which there is no universally accepted characterization test, making it difficult to determine and control the quality, safety, and efficacy of herbal medicines containing such a poorly defined natural product. In fact, one of the most serious obstacles to the promotion of herbal chamomile products is adulteration. Partial Least Squares Discriminant Analysis (PLS-DA) was used to construct a model that classifies and discriminates samples of interest. Since this type of model enables assignment of new samples into previously determined groups in an unbiased fashion, it would be very useful for the quality control of many natural products and dietary supplements. The batch samples can be automatically acquired, processed, and class predicted. And as before it was possible to identify these compounds through a library. In this case no acc mass but rich fragmentation and a huge repository --------------- there is no universally accepted characterization of chamomile, making it difficult to determine and control the quality, safety, and efficacy of herbal medicines containing such a poorly defined natural product. In fact, one of the most serious obstacles to the promotion of herbal chamomile products is adulteration. Partial Least Squares Discriminant Analysis (PLS-DA) was used to construct a model that classifies and discriminates samples of interest. Since this type of model enables assignment of new samples into previously determined groups in an unbiased fashion, it would be very useful for the quality control of many natural products and dietary supplements. The batch samples can be automatically acquired, processed, and class predicted. Sin e this is MS EI compounds were also indidtified.
LC/MS & GC/MS profiling at NCNPR, Mississippi
• Can be an effective approach for authenticity assessments.
• Applicable to both raw materials and dietary supplement extracts and tablets.
• Chemical information collected can also give other insights• Freshness of a product.• Safety of a product
Some insights to Deconvolution & Identification with Mass Hunter
Deconvoluted spectrum
Selected feature
Deconvoluted chromatogram
GC/MS analysis with
Electron Ionization
Mass spectral library from NIST
Total Ion Chromatogram
Presenter
Presentation Notes
Here we see how the a mass spec finds the molecular features that are used to feed chemomtric modelling. In this example we again show EI data from a GC/MS and we see how the deconvoluted chromatogram reveals far more compounds than is evident simply by viewing a total ion chromatogram. Mass spec data is also helpful because a set of ions identified to be eluting together can be reconstructed as a mass spectrum and searched against a library. Identifying features in particular the ones used as markers of difference is considerede important when creating differentiating models so there is confidence that the chosen markers of difference are reliable and endogenous to the food. Custom libraries has been mentioned for the previous LC/MS illustrations but for GC/MS there are much greater repository publically available spectral libraries that can be applied. In our example here you can see in the bottom right a deconvoluted spectrum and proposed library match from NIST. In this case the match is for a compound for which the common name if safranal. In fact this file comes from a Saffron study at Institute of Technology in Prague and Safranal is a key component in that product.
Some insights to Deconvolution & Identification with Mass Hunter
Deconvoluted spectrum
Selected feature
Deconvoluted chromatogram
GC/MS analysis with
Electron Ionization
Mass spectral library from NIST
Safranal
Presenter
Presentation Notes
Here we see how the a mass spec finds the molecular features that are used to feed chemomtric modelling. In this example we again show EI data from a GC/MS and we see how the deconvoluted chromatogram reveals far more compounds than is evident simply by viewing a total ion chromatogram. Mass spec data is also helpful because a set of ions identified to be eluting together can be reconstructed as a mass spectrum and searched against a library. Identifying features in particular the ones used as markers of difference is considerede important when creating differentiating models so there is confidence that the chosen markers of difference are reliable and endogenous to the food. Custom libraries has been mentioned for the previous LC/MS illustrations but for GC/MS there are much greater repository publically available spectral libraries that can be applied. In our example here you can see in the bottom right a deconvoluted spectrum and proposed library match from NIST. In this case the match is for a compound for which the common name if safranal. In fact this file comes from a Saffron study at Institute of Technology in Prague and Safranal is a key component in that product.
The benefits of QTOF mass spec. 3x10
0
0.1
0.20.3
0.4
0.5
0.60.7
0.8
0.9
11.1
1.2
Cpd 100: + Compound Spectrum (14.886 min)
107.0852[C8 H11]+
121.101291.0547
150.1054[C10 H14 O]+79.0544
[C6 H7]+
65.0389[C5 H5]+ 135.0808
[C9 H11 O]+51.0236[C4 H3]+
15.0259
29.0056
59.0521
Counts vs. Mass-to-Charge (m/z)40 50 60 70 80 90 100 110 120 130 140 150 160
Accurate massSpectrum
Measured m/z 150.1054 ► [C10 H14 O]+ ► SAFRANALCalculated [C10 H14 O]+ m/z 150.1039 ►Δ -9.88 ppm
Isotope pattern135.0808 ►[C9 H11 O]+
107.0852 ►[C8 H11]+
91.0547 ►[C7 H7 ]+
65.0389 ► [C5 H5 ]+
17
5x10
01234567
150.1054[C10 H14 O]+
151.1080
Mass-to-Charge (m/z)149.5 150 150.5 151 151.5
Fragments?
Mass spectral fit from NIST
Presenter
Presentation Notes
The data from the previous slide was in fact produced by a GC QTOF . It is typical to search GC QTOF data in the same way is GC single quad data would be searched because it is unit mass resolution spectra that dominate in the publicly available libraries like NIST. However the accurate mass component of GC QTOF data is not wasted in this process because once a proposed asignment is made it is then possible to asses the likelihood of this assignment, by investigating if the accurate mass measurements coming from the QTOF are consistent with the formulae of the molecule and it’s likely fragments.
The benefits of QTOF mass spec
5x10
00.20.40.60.8
11.21.4 151.1114
([C10 H14 O]+H)+
123.1161([C9 H14]+H)+
107.082181.0697
([C6 H8]+H)+
Mass-to-Charge (m/z)70 80 90 100 110 120 130 140 150
Measured m/z 151.1114 ► ([C10 H14 O]+H)+ ► SAFRANALCalculated ([C10 H14 O]+H)+ m/z 151.1117 ►Δ 2.26 ppm
Positive Chemical Ionization with accurate mass MS and MS/MS
spectra.
Presenter
Presentation Notes
When investigating natural compounds it’s not always so easy to then buy such a compound for further confirmation but the GC QTOF offers additional capabilities to increase confidence in an assignment. Firstly it offer the analyst a chance to see the molecule under an alternative ionization mechanism such as Chemical Ionization and secondly it offer the analyst a chance to perform MSMS experiments using chemically induced fragmentation. This orthogonal information adds further confidence to an identification especially because all data is once again collected with accurate mass.
The benefits of QTOF mass spec
40
Unknown compound identification: Full spectral information → Mass spectral library search Exact mass Molecular ion (PCI) Product ion spectra → Identity confirmation
GC –QTOF MS
SAFRON AUTENTICATIONAgilent 7200 GC-QTOFMS
Differentiation according to country of origin
Link
Hosted by
Presenter
Presentation Notes
These are the conclusions from ICT based on the Saffrom study used in this illustration. A full explanation of their work can be found at the link shown which is a presentation by Professor Jana Hajslova who leads the group in question
Identity Fingerprinting using DART QTOF
• 6530 Agilent Q-TOF + DART source• Fast analysis• Differentiation possible between
different types of cinnamon• Markers of difference were identified
PCA plot derived from 7 compounds below.
C. verum=True Cinnamon Various varieties of cassia cinnamon
Mass spectrum for one type of Cassia cinnamon called Cinnamon burmannii
Journal Publication Link
Presenter
Presentation Notes
We’ve talked about LCMS and GCMS but there is a 3rd approach in organic mass spectrometry which is proving increasingly popular for authenticity testing of botanicals. It’s called ambient Mass spectrometry and it doesn’t involve any chromatography. In this example we are looking at a cinnamon study. Due to the high cost of what is called true cinnamon, cassia cinnamon is often used as a substitute and it is therefore necessary to discriminate between these two main types and to detect food adulteration. Cassia cinnamon contains up to 1% coumarin, whereas true cinnamon contains only trace quantities at about 0.004%. But methods for this and associated compounds are often time-consuming. All the marker compounds are present in all the authentic samples of each species. Their differentiation is determined by the relative concentration of the markers in each species. This approach will be very useful to predict whether ‘true cinnamon’ has been adulterated with other cinnamons. Knowing the identity of these compounds, routine analysis of cinnamon could be done by DART with a single quadruple MS
Some other publications on active component assesment in functional foods and dietary supplements. – Look below in this webinar console for the direct links… • Rapid Simultaneous Analysis of Valerenic Acids UHPLC
Application Note Link
• Quantitation of Amygdalin in almonds LC/MS.. Journal Link
• Quantitation of Mitragynine & Other Alkaloids in Mitragyna speciosa (or Kratom product ) using SFC/MS……..Application Note Link Journal Link
• Quantitation of Bioactive Polyphenols & Secoiridoids in Black Olives from different de-bittering processes using LC/MS. Journal Link
• Characterization and quantitation of yohimbine and its analogs in botanicals and dietary supplements using LC/MS for determination product adulteration.Journal Link
For more information visit:www.agilent.com
