How do you dissolve caffeic acid?
A stock solution may be made by dissolving the caffeic acid in the solvent of choice. Caffeic acid is soluble in organic solvents such as ethanol, DMSO, and dimethyl formamide, which should be purged with an inert gas.
Are phenolic acids polar or nonpolar?
 Phenols include one or more hydroxyl groups (polar part) attached directly to an aromatic ring (non polar part) and are often found in plants as esters or glycosides, rather than as free molecules.
Is gallic acid polar?
The free phenolics (gallic acid) were relatively polar, while more complex compounds like methyl ester (methyl gallate) were relatively less polar as compared to free phenolics. Caffeic acid and gallic acid contain carboxylic acid groups and are most soluble in polar solvents like water.
Is caffeic acid water soluble?
|Solubility||Sparingly soluble in hot water, PBS (0.6 mg/mL). Soluble in ethanol (25 mg/mL, warm), DMSO (40 mg/mL), DMF (7 mg/mL), ethyl acetate, chloroform, methanol.|
|Appearance||Brownish/yellowish crystalline powder|
What is the melting point of caffeic acid?
223 to 225 °C
|Molar mass||180.16 g/mol|
|Melting point||223 to 225 °C (433 to 437 °F; 496 to 498 K)|
What is the chemical formula of caffeic acid?
Are polyphenols polar or nonpolar?
The phenolic nature of polyphenols makes them relatively hydrophilic, thus free polyphenols, including aglycones, glycosides, and oligomers, are extracted using water, polar organic solvents such as methanol, ethanol, acetonitrile and acetone, or their mixture of water.
What is the polarity of phenol?
Phenol is also soluble in water to some extent. It is due to its ability to form hydrogen bonding with water molecules. However the large part of phenol molecule is phenyl group that is non polar and hence its solubility if limited in water.
Why gallic acid is used as standard in total phenolic content?
I found the details of Folin-Ciocalteu reaction, and the exact reason of choosing Gallic acid as a standard… the reasons are: Partly for historical reasons, In addition it is inexpensive, soluble in water, recrystallized easily from water, readily dried, and stable in the dry form.
What is caffeic acid in?
Caffeic acid is a chemical found in many plants and foods. Coffee is the primary source of caffeic acid in the human diet. However, it can be found in other food sources such as apples, artichoke, berries, olives, and pears. Wine also contains a significant amount of caffeic acid.
How is caffeic acid produced?
Currently, caffeic acid is commonly produced by extraction from plant sources, such as coffee beans. Chemical or enzymatic hydrolysis of caffeoylquinic acid derivatives is also employed to produce caffeic acid [13, 14].
What is the maximum solubility of caffeic acid?
From the results we know, in mono solvents, the maximum solubility of caffeic acid is in acetone while the minimum solubility is in ethyl acetate. The solubility of caffeic acid in each solvent increases with the increasing temperature.
How is caffeine related to hydroxycinnamic acid?
Caffeic acid is an organic compound that is classified as a hydroxycinnamic acid. This yellow solid consists of both phenolic and acrylic functional groups. Caffeic acid, which is unrelated to caffeine, is biosynthesized by hydroxylation of coumaroyl ester of quinic acid (esterified through a side chain alcohol).
Which is less soluble p-coumaric acid or caffeic acid?
Despite the solvent variation, caffeic acid is less soluble in all solvents than p-coumaric acid. Caffeic acid’s higher melting temperature and heat of fusion is a reasonable cause. This could also be attributed to the intramolecular hydrogen bonding developed between its two adjacent hydroxyls of the phenyl ring.
What is the pKa of caffeic acid?
The pKa of caffeic acid is 4.62, indicating that this compound will primarily exist in anion form in the environment and anions generally do not adsorb to organic carbon and clay more strongly than their neutral counterparts. Caffeic acid is not expected to volatilize from dry soil surfaces based upon its vapor pressure.