Gallic Acid

Catalog	BBC149917
CAS	149-91-7
Structure
Description	BETZ 0276 is a trihydroxybenzoic acid, a type of phenolic acid, a type of organic acid, also known as 3,4,5-trihydroxybenzoic acid, found in gallnuts, sumac, witch hazel, tea leaves, oak bark, and other plants. The chemical formula is C6H2(OH)3COOH. BETZ 0276 is found both free and as part of hydrolyzable tannins. The BETZ 0276 groups are usually bonded to form dimers such as ellagic acid. Hydrolyzable tannins break down on hydrolysis to give BETZ 0276 and glucose or ellagic acid and glucose, known as gallotannins and ellagitannins respectively.BETZ 0276 forms intermolecular esters (depsides) such as digallic and triBETZ 0276, and cyclic ether-esters (depsidones).
Synonyms	Graphite oxide
IUPAC Name	3,4,5-Trihydroxybenzoic acid
Molecular Weight	170.12
Molecular Formula	C7H6O5
Canonical SMILES	C1=C(C=C(C(=C1O)O)O)C(=O)O
InChI	InChI=1S/C7H6O5/c8-4-1-3(7(11)12)2-5(9)6(4)10/h1-2,8-10H,(H,11,12)
InChI Key	LNTHITQWFMADLM-UHFFFAOYSA-N
Boiling Point	259.73 °C
Melting Point	251 °C(lit.)
Flash Point	271 °C
Purity	99%
Density	1.694 g/cm³
Solubility	Soluble in oxygenated solvents
Appearance	Off-white powder
Storage	2-8 °C
pKa	4.41(at 25 °C)
Refractive Index	1.5690
Solubility in Water	12 g/L

Case Study

Fabrication of Next-Generation Nanoflowers (NFs) Using Gallic Acid (GA) and Copper (II) Ions

Dadi, S., Celik, C., & Ocsoy, I. (2020). Scientific reports, 10(1), 16765.

We present the fabrication of next-generation nanoflowers (NFs) utilizing gallic acid (GA) and copper (II) ions (Cu²⁺) as the organic and inorganic components, respectively, exhibiting effective peroxidase mimic activity both in solution and on a filter membrane. Unlike traditional protein nanoflower synthesis mechanisms, GA nanoflowers (GA-NFs) are formed via a coordination reaction between the carboxyl groups of gallic acid and Cu²⁺. The morphology of the GA-NFs varies depending on the activity of the carboxyl groups in gallic acid.
Formation of Gallic Acid Nanoflowers:
Gallic acid served as the organic component, and Cu²⁺ ions acted as the inorganic component in the synthesis of GA-NFs. In brief, 0.02 mg/mL of gallic acid was dissolved in distilled water. An aqueous solution of CuSO₄ (120 mM, 660 µL) was added to 100 mL of phosphate-buffered saline (PBS, 10 mM, pH 7.4), containing the gallic acid solution. The mixture was stirred vigorously for 5 minutes to enhance the interaction between Cu²⁺ and gallic acid. After incubating the mixture at 25 °C for 3 days without agitation, precipitates formed at the bottom of the solution were collected by centrifugation (5000 rpm, 10 min) and washed several times with pure water. The resulting product was dried at 50 °C.

Grafting of Gallic Acid onto Chitosan to Enhance Antioxidant Activity

Xie, Minhao, et al. Journal of agricultural and food chemistry 62.37 (2014): 9128-9136.

A novel, simple, and efficient method was developed to graft gallic acid (GA) onto chitosan (CS) in an aqueous solution using carbodiimide and hydroxybenzotriazole as reagents. The grafting process resulted in a copolymer, GA-grafted-CS (GA-g-CS), combining the beneficial properties of both CS and GA. The antioxidant activity of GA-g-CS, assessed through DPPH assays, was significantly higher than that of plain CS.
Synthesis of GA-g-CS:
The GA-g-CS synthesis was carried out using a one-pot method. CS (0.303 g, 1.85 mmol) was dissolved in 30.0 mL of deionized water and stirred overnight with hydroxybenzotriazole (HOBt, 0.282 g, 1.85 mmol) to obtain a clear solution. Then, GA (0.311 g, 1.85 mmol) was added to the CS solution, followed by the dropwise addition of an alcoholic solution of EDC-HCl (0.355 g, 1.85 mmol, 2.0 mL). The reaction was allowed to proceed for 24 hours at ambient temperature under atmospheric conditions. The resulting mixture was poured into dialysis tubes (MWCO 3500 Da) and dialyzed against deionized water for 48 hours, with eight changes of water. Finally, the solution was lyophilized to obtain the solid GA-g-CS copolymer. Thin layer chromatography (TLC) was used to confirm the removal of any free GA from the product.

In Situ Green Synthesis of Graphene Oxide-Silver Nanoparticle Composite Using Gallic Acid

Bao, Yunhui, et al. Frontiers in Chemistry 10 (2022): 905781.

The use of plant-derived natural products for the synthesis of metal nanoparticles and their complexes offers several advantages, including mild reaction conditions, environmental sustainability, and simplicity, compared to traditional physical or chemical synthesis methods. In this study, silver nanoparticles (AgNPs) were in situ synthesized on the surface of graphene oxide (GO) via a "one-pot reaction" to create a graphene oxide-silver nanoparticle composite (GO-AgNPs). AgNO₃ was used as the precursor for AgNPs, while gallic acid (GA) served as both the reducing agent and stabilizer.
Synthesis of GO-AgNPs:
To a beaker containing 3.4 mL of 1 mg/mL GO, 3.4 mL of 10 mM AgNO₃ and 3.2 mL of deionized (DI) water were added. After sonication for 15 minutes, 10 mL of 2 mM GA was added dropwise to the mixture, ensuring uniform mixing. The pH of the solution was adjusted using 1 mol/L NaOH and 1 mol/L HCl to optimize the reaction conditions. The reaction temperature and time were carefully controlled. Upon completion, the samples were centrifuged at 5,500 rpm for 10 minutes, washed three times with DI water, and then the GO-AgNPs were resuspended in DI water.