It happens that plant extract obtained by methanol /ethanol/ extraction contains not only organic moieties /monosaccharides, pigments, phenolics, lignols, water soluble fation of lignin, tannins, aminoacids, disaccharides, some polar derivatives of terpenes, low molecular weight hemicellulose fractions and oligosaccharides, organic acids, vitamins glycosides, etc./ but also some inorganic ones. Most of oganic compounds are reversibly soluble after solvent evaporation.

Wood, leafs and needles contain also inorganic compounds /Na+, K+, Ca2+, Mg2+, P5+, Si2+...., and salts of inorganic and organic acids, as well. The crystals insoluble in methanol might belong to this category.These moieties are the main case of ash formation on plants burning.

If your sample was fresh and not dried prior to extractin, the water in it dissolved in methanol thus increasing its ability to dissolve inorganic compouns. When the solution of extractives was getting colder, the less soluble compounds crystallized.

After drying, when methanol and water evaporated, you obtained crystals insoluble in CH3OH.

You should determine dry weight of your sample and water content and try to dissolve the crystals in corresponding methanol water solvent at methanol boiling p. temperature.

To know wether cystals are inorganics, try melting point /should be much over 100 oC, or burn it over flame. If crystals burn without leaving ash they are organic moiety. If they do not burn or burn with an ash formation, the crystals are most probably inorganics or salts of carboxylic acids..

You could get the crystals analysed for more relevant information, finally.

R.S.

Most of time crystal are observed in case of pure compounds. You can get more crystal with treatment with methanol and put overnight without disturbing it. You will get crystals.

Gudluck

:)

I ever observed the same case. I washed the crystal in methanol. May it the major compound in that plant.

It happens that plant extract obtained by methanol /ethanol/ extraction contains not only organic moieties /monosaccharides, pigments, phenolics, lignols, water soluble fation of lignin, tannins, aminoacids, disaccharides, some polar derivatives of terpenes, low molecular weight hemicellulose fractions and oligosaccharides, organic acids, vitamins glycosides, etc./ but also some inorganic ones. Most of oganic compounds are reversibly soluble after solvent evaporation.

Wood, leafs and needles contain also inorganic compounds /Na+, K+, Ca2+, Mg2+, P5+, Si2+...., and salts of inorganic and organic acids, as well. The crystals insoluble in methanol might belong to this category.These moieties are the main case of ash formation on plants burning.

If your sample was fresh and not dried prior to extractin, the water in it dissolved in methanol thus increasing its ability to dissolve inorganic compouns. When the solution of extractives was getting colder, the less soluble compounds crystallized.

After drying, when methanol and water evaporated, you obtained crystals insoluble in CH3OH.

You should determine dry weight of your sample and water content and try to dissolve the crystals in corresponding methanol water solvent at methanol boiling p. temperature.

To know wether cystals are inorganics, try melting point /should be much over 100 oC, or burn it over flame. If crystals burn without leaving ash they are organic moiety. If they do not burn or burn with an ash formation, the crystals are most probably inorganics or salts of carboxylic acids..

You could get the crystals analysed for more relevant information, finally.

R.S.

Dr Rastislav SOLÁR has provided a possible answer to your question. Thank you Sir for the detailed explanation. A lot to learn from that