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Terpin production according to nutrients

Chimera

Genetic Resource Management
Veteran
That's nonsense that UPLC-MS is the best method for terps, we've run a fully validated protocol with spike recovery using standards and GC-FID is the method. And we do have UPLC and MS, but MS is not needed unless you are trying to identify compounds for which you don't have a standard. Which method do you use in your laboratory OO, do you use UPLC-MS? Or are you simply speaking generalities?

As far as genes regulating terps, it's true that genes control the terpene finger print (overall profile), but specific terps fluctuate to a degree depending on epigenetic factors.

Even on a single table, where all plants are fed the same nutrients, there is some variation of levels of specific terps, whereas other terps are more stable.

You can't gain these results from a few tests, the true story comes out when you test batches of the same flowers grown in standardized conditions, time and time again, and start to compare results of the same cultivars between runs. Overall plants will retain the same fingerprint, but do show some variation between the relative components.

It's more about environment and consistent conditions- light exposure and intensity is just a single factor. Also running a single sample of bud from a crop is not really indicative of the average of the flowers across the whole crop. Testing can be manipulated if a sound sampling protocol and validated methodology is not used, so beware of this when interpreting single results from a lab... there is much more to the story.

-Chimera
 
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Only Ornamental

Spiritually inspired agnostic mad scientist
Veteran
That's nonsense that UPLC-MS is the best method for terps, we've run a fully validated protocol with spike recovery using standards and GC-FID is the method. And we do have UPLC and MS, but MS is not needed unless you are trying to identify compounds for which you don't have a standard. Which method do you use in your laboratory OO, do you use UPLC-MS? Or are you simply speaking generalities?...
My answer was a response to FatherEarth's statement who's looking for a sophisticated no-heat method for, as I understand, also unknown terpenes (could be sterols FWIW).
Regarding known mono- and not too highly 'functionalised' sesquiterpenes, you're mostly right and regarding cannabis, where I have no personal experience with, I believe you instantaneously that GC-FID is a better way to go in many aspects (ease of manipulation, cost etc.).
Certainly, everything highly depends on the column but also all the other instruments and methods used, MS isn't MS. Besides, the commonly used LC columns aren't usually that great for small hydrocarbons and I wouldn't start with UPLC for those, it certainly isn't the smartest idea and there has to be an MS coupled to it; coupling two instruments is also more work and effort than a GC-FID that 'comes in one piece'.
The labs I work/-ed with use/-d UPLC-MS as standard for screening, profiling, and 'omics' whereas GC becomes more and more secondary or even obsolete. Though, essential oils aren't usually on the menu but if so, then GC-FID was/is still valuable.
There is not one perfect method for everything and there's always an exception for every rule...

I didn't specify that my response was hypothetical as I was under the assumption that this is quite obvious... guess it wasn't. Thanks for pointing that out!
 
Chimera is right...UPLC is for heat degradable organic compounds such as THCA (acid) since GC MS decarboxylates the acid to THC.
 
Ohh snap!! Just realized this is Chimera the breeder who popped into the conversation. What a coincidence...got some oxacan highland mexican gear heading this way as we speak.Can't wait to see how it performs in my island. Back in the 90's and till the early 2000's much of the cannabis available here was outdoor "bricks" imported from mexico. I miss the giggly,uplifted,cerebral,long-lasting buzz and the notes of spice, roasted coffee and berries that predominated during those days. Now a days it all seems to have been replaced by the sleepy head kush hybrids grown locally.I am all for variety, so hopefully these can spice things up a bit. Kind regards, and thanks for taking your time to put your "gold nuggets" worth of knowledge.
 
Why do most people want to discuss theory and not how to grow the best weed in reality?​

Probably the biggest reason for that is they don't think they can anyway.​

It's a selffullfilling prophecy.​
 

Sam_Skunkman

"RESIN BREEDER"
Moderator
Veteran
Hey Chimera,
I was talking with a proton NMR guy who says that proton NMR is the best way to determine terpenes as all the analysis is done with zero sample destruction and all the terpenes retain their original forms while a GC alters the forms into other compounds? As I have told you we used GC-FID for 2 decades for terpene analysis.
I told hin that a GC is closer to people smoking the herb or resin, and that is what we wanted. If heat alters the analysis then heat is altering what people smoke, not many people consume Cannabis in a way that does not use heat. People use to also tell me to use HPLC for Cannabinoid analysis but I was more interested in the neutral forms of Cannabinoids not the acid forms and neutral side by side.
I understand that folks that eat Cannabis products are interested in the neutral forms and the acid forms.
-SamS

That's nonsense that UPLC-MS is the best method for terps, we've run a fully validated protocol with spike recovery using standards and GC-FID is the method. And we do have UPLC and MS, but MS is not needed unless you are trying to identify compounds for which you don't have a standard. Which method do you use in your laboratory OO, do you use UPLC-MS? Or are you simply speaking generalities?

As far as genes regulating terps, it's true that genes control the terpene finger print (overall profile), but specific terps fluctuate to a degree depending on epigenetic factors.

Even on a single table, where all plants are fed the same nutrients, there is some variation of levels of specific terps, whereas other terps are more stable.

You can't gain these results from a few tests, the true story comes out when you test batches of the same flowers grown in standardized conditions, time and time again, and start to compare results of the same cultivars between runs. Overall plants will retain the same fingerprint, but do show some variation between the relative components.

It's more about environment and consistent conditions- light exposure and intensity is just a single factor. Also running a single sample of bud from a crop is not really indicative of the average of the flowers across the whole crop. Testing can be manipulated if a sound sampling protocol and validated methodology is not used, so beware of this when interpreting single results from a lab... there is much more to the story.

-Chimera
 
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Only Ornamental

Spiritually inspired agnostic mad scientist
Veteran
Hey Chimera,
I was talking with a proton NMR guy who says that proton NMR is the best way to determine terpenes as all the analysis is done with zero sample destruction and all the terpenes retain their original forms while a GC alters the forms into other compounds? ...
Hi Sam,
Out of curiosity, can he do that with a complex mixture of similar constituents and accurately determine their concentration? I mean, theoretically it's feasible (especially with high end machines) and I've seen conceptual work with sugars and phenolics but how does it look with everyday life samples such as essential oils?
It's quite funny that every expert thinks his 'strategy X' is the best; being unbiased in such a situation isn't always easy... (dam, did I just fail regarding UPLC-MS?)
 

Sam_Skunkman

"RESIN BREEDER"
Moderator
Veteran
He has worked with NMR for 30 years and says yes. And in solid, liquid or gas state, he can sample them all with no damage or changes to the samples. He also said the peaks will overlap and you may need to use the equivalent of MS to separate them.
Here is a paper using NMR for Cannabis not sure if others posted:

http://cannabisinternational.org/info/bio-active-cannabinoids.pdf

My friend says:
The ability to identify the trace components depends on the signal/noise ratio in the NMR. Certain peaks in the NMR correspond to more protons such as the peak for a methyl group which will be three times larger than a peak for a single hydrogen atom in the same molecule. So the larger peaks can be used to id the compound if "you can see the forest thru the trees". Multidimensional NMR techniques can be used to deconvolute mixtures resulting in overlapping signals. Furthermore, NMR provides information on bond connectivity between atoms by looking at coupling between resonances of different spin systems (protons and carbons).

All 80+ cannabinoids and 140 terpenoids, if they are present in the extract or concentrate, will be visible but the level of sensitivity of NMR can be limited due to the amount on the component present and it's relative concentration to the other major components present. That means that there could be a window in the spectrum where a trace component has a peak (resonance) and that single peak could be used to id that particular compound even if the other peaks corresponding to that compound are obscured by that larger peaks of the major components present.



I get the feeling that NMR use with Cannabis is really just starting and folks using NMR will find uses for analysis of certain Cannabis compounds, if that includes terpenes like I hope then I welcome it. To allow the sample to be unchanged by the analysis is interesting.

-SamS


Hi Sam,
Out of curiosity, can he do that with a complex mixture of similar constituents and accurately determine their concentration? I mean, theoretically it's feasible (especially with high end machines) and I've seen conceptual work with sugars and phenolics but how does it look with everyday life samples such as essential oils?
It's quite funny that every expert thinks his 'strategy X' is the best; being unbiased in such a situation isn't always easy... (dam, did I just fail regarding UPLC-MS?)
 

Only Ornamental

Spiritually inspired agnostic mad scientist
Veteran
He has worked with NMR for 30 years and says yes. And in solid, liquid or gas state, he can sample them all with no damage or changes to the samples. He also said the peaks will overlap and you may need to use the equivalent of MS to separate them. That's the interesting part IMO.
Here is a paper using NMR for Cannabis not sure if others posted:

http://cannabisinternational.org/info/bio-active-cannabinoids.pdf
They only used NMR for structure elucidation of isolated pure compounds...
My friend says:
...
All 80+ cannabinoids and 140 terpenoids, if they are present in the extract or concentrate, will be visible but the level of sensitivity of NMR can be limited due to the amount on the component present and it's relative concentration to the other major components present. That means that there could be a window in the spectrum where a trace component has a peak (resonance) and that single peak could be used to id that particular compound even if the other peaks corresponding to that compound are obscured by that larger peaks of the major components present.
That's the point I wonder about: What I've seen so far is that it works in theory but the applicability for a specific sample has to be shown first and the way you put it, he hasn't tested cannabis either.

I get the feeling that NMR use with Cannabis is really just starting and folks using NMR will find uses for analysis of certain Cannabis compounds, if that includes terpenes like I hope then I welcome it. To allow the sample to be unchanged by the analysis is interesting.
Likely all published structures of cannabis constituents and most natural compounds have, at some point, been determined with NMR (a few might have been elucidated with X-ray crystallography). I doubt that NMR will become a part of 'lab testing' but things change fast in this environment...
-SamS
Thanks for elaborating!
 
NMR machines are very,very,very expensive, not to mention the helium gas needed to run the damn thing. I don't know of a single lab that does cannabis analysis that owns one of those.Besides, NMR is used to determine the electronic environment of specific nuclei in order to elucidate structure. You might find them in academia research labs and pharma industry labs, not in lab testing for cannabinoids and terpenes. Terpenoids are volatile,meaning they go into gas phase at relatively low temperatures but they don't degrade under GC conditions.They boil off and evaporate and in the gaseous phase then they get separated by their affinity to the stationary phase which is the column they travel through.On their way out they are broken down into fragments and the ions are identified by their mass to charge ratio.
 

Only Ornamental

Spiritually inspired agnostic mad scientist
Veteran
...in the gaseous phase then they get separated by their affinity to the stationary phase which is the column they travel through.On their way out they are broken down into fragments and the ions are identified by their mass to charge ratio.
Guess you just mixed GC and MS up a little bit ;) .
Besides, unlike other chromatographic methods it's usually (with exceptions) not primarily the affinity for the column but the difference in gas pressure that separates sample constituents...
 
A

acridlab

I don't have any science to back it up,, but I have grown my house strain with at least 8 different nute lines,, and I have gotten 8 different flavors..so I would say,, yes,, dif nutes can change things..
 
GC is a separation method and MS is a qualitative/quantitative identification method. Think of these things as modules different techniques get combined into one same piece of equipment. First you separate then you identify.
Acridlab…how would you rate those differences??Subtle...like in a bit more/less piney ext..….or drastic like it went from pine to mango? I doubt the latter was the case.Were you growing that strain from seed or clone>Where the clones from the same mother? I am pretty sure that if you grew a strain from clones, from the same mother, under homogeneous environmental conditions, with different nutrient concoctions ( assuming that they all contain the necessary micro/macro nutrients) you would only get different ratios of the same terpenoids, not completely different terpenoids on each.
 
A

acridlab

GC is a separation method and MS is a qualitative/quantitative identification method. Think of these things as modules different techniques get combined into one same piece of equipment. First you separate then you identify.
Acridlab…how would you rate those differences??Subtle...like in a bit more/less piney ext..….or drastic like it went from pine to mango? I doubt the latter was the case.Were you growing that strain from seed or clone>Where the clones from the same mother? I am pretty sure that if you grew a strain from clones, from the same mother, under homogeneous environmental conditions, with different nutrient concoctions ( assuming that they all contain the necessary micro/macro nutrients) you would only get different ratios of the same terpenoids, not completely different terpenoids on each.
oh,, all clones from same mothers, too


I would say subtle for the most part... For instance,, my og18 with advanced, tastes super piney, while h&g makes it taste more chemmy funk... And my sour kush is straight gasoline/green apple with advanced,and just green apple/cleaner with h&g.. The only time things changed a lot, was when I tried gh Lucas with flora nectar.. Made my sour smelll and taste like just like the flora nectar".. The berry one..
 

Only Ornamental

Spiritually inspired agnostic mad scientist
Veteran
Ok,teach me….difference in pressure of what gas????
Vapour pressure of the sample ;) . It's just an equilibrium between adhesion/desorption and usually not an actual interaction with the stationary phase as seen in liquid chromatography between sample and silica.
 
Yeah,those are very reasonable variations.Chimera summed it up by using the term epigenetics...most living things tend to be ruled by pretty complex systems with lots of modularity and cascading mechanisms that give way to lots of variation and diversity as means to achieve evolution.
 
Vapour pressure of the sample ;) . It's just an equilibrium between adhesion/desorption and usually not an actual interaction with the stationary phase as seen in liquid chromatography between sample and silica.
Stop it now... your'e just making a fool of yourself. Do you know anything about what you're copy/pasting????
 

Only Ornamental

Spiritually inspired agnostic mad scientist
Veteran
FWIW, assuming I were a granny sitting in her rocking chair in a basement with the Encyclopaedia Britannica on her lap copy-pasting stuff, at least I'd be doing it correctly and not stuff like
GC conditions.They boil off and evaporate and in the gaseous phase then they get separated by their affinity to the stationary phase which is the column they travel through.On their way out they are broken down into fragments and the ions are identified by their mass to charge ratio
;) . A GC hasn't m/z as readout. Sure, you can talk your way out by ignoring that we were talking about GC-FID and saying that in your case it's a GC-MS...
Small advice: Don't try to outsmart me, you'd utterly fail (cause even I have difficulties doing so ROFL).

And now, please get back to topic!
You could for example prove that you're actually able to read the instruction manual for your brain by explaining to the users here how epigenetic regulation links plant nutrients with mono-/sesquiterpene biosynthesis.
 
Just read before you copy/paste cause if you look back through my posts I've not mentioned anything else other than GC-MS, which is the standard for organic molecules. You show your ignorance just mentioning FID for terpene analysis. Where did you get your Ph.D., did it come with your happy meal? I won't waste any more of my time with you dude, I just hope that people that are interested in learning about these subjects realize that listening to you they might end regurgitating a lot of nonsense.
 
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