Antioxidant Activity Of Gallic Acid Research Articles

Antioxidant activates of new carbohydrate based gallate derivatives: A DFT study

Biocompatibility, biodegradability, low-cost and rich chemistry of carbohydrates is among the most important features that make them promising materials for biomedical applications. Nowadays many research focused on exploring new polymeric antioxidant based on natural and synthetic carbohydrates. In this context, the antioxidant activity of Gallic Acid (Ga), Glucose Gallate (GG) and Glucose conjugated gallic acid by inverse ester bond (GGI) as two types of glucose conjugated derivatives of gallic acid containing, respectively, electron with-drawing and electron-donating groups as model molecules for polysaccharide gallate were studied using DFT (density functional theory) method. The radical scavenging capability of the compounds was exploded through BDE, SET-PT and SPLET mechanisms. Moreover, the solvent effects on antioxidant activities were investigated. It found that BDE mechanism is the best descriptor for evaluation of antioxidant activities in both gas phase as well as in the presence of solvents and GG is the most reactive antioxidant compound. Also, it was concluded that the antioxidant activities do not reduce by derivation, dramatically. In addition to the above mentioned mechanisms, the HOMO and LUMO energies and electrostatic potential maps for the compounds were computed and applied to predict the antioxidant activity of the compounds.

Comparing the antioxidant activity of gallic acid and its alkyl esters in emulsion gel and non-gelled emulsion

In this study, antioxidant capacity of gallic acid and its alkyl esters in emulsion gel was compared with non-gelled emulsion to determine the role of mass transport on their efficiency. Lauryl gallate exhibited higher antioxidant activity than gallic acid and ethyl gallate in emulsion gel and non-gelled emulsion. In emulsion gel, the synergistic effects in the initiation stage for gallic acid + ethyl gallate, gallic acid + lauryl gallate, and ethyl gallate + lauryl gallate were 78.28 %, 68.46 %, and 60.04 %, respectively. In non-gelled emulsion, the synergistic effects were 52.78 %, 39.02 %, and 22.30 %, respectively. In both emulsion gel and non-gelled emulsion, the longest induction period and propagation period was observed in samples containing gallic acid + lauryl gallate. The effectiveness of antioxidants in emulsion gel was lower than non-gelled emulsion. This reduction in antioxidant activity can be due to the limited ability of antioxidants to be transferred to the interfacial area.

Polyethylene Glycol-Stabilized Zein Nanoparticles Containing Gallic Acid

SUMMARYResearch backgroundGallic acid is a polyphenol with antioxidant and antitumor activities; however, its use as a nutraceutical or drug is hindered by its low bioavailability. Zein is a natural protein found in corn and has been applied as nanoparticle drug carrier. In this study, zein nanoparticles were obtained and stabilized with polyethylene glycol (PEG) as gallic acid carriers.Experimental approachNanoparticles were obtained by the liquid-liquid method and characterized in terms of mean size, polydispersity index, zeta potential, morphology, solid-state interactions and encapsulation efficiency/drug loading. The stability of nanoparticles was evaluated in simulated gastrointestinal fluids and food simulants, and the antioxidant activity was determined by the scavenging of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical.Results and conclusionsZein nanoparticles containing gallic acid were obtained and stabilized only in the presence of PEG. Under optimal conditions, nanoparticles with mean size <200 nm, low polydispersity index (<0.25) and negative zeta potential (−20 mV) were obtained. The gallic acid encapsulation efficiency was about 40%, loading about 5%, and it was encapsulated in an amorphous state. Fourier transform infrared spectroscopy (FTIR) did not identify chemical interactions after gallic acid nanoencapsulation. Zein nanoparticles were more prone to release the gallic acid in gastric than intestinal simulated medium; however, more than 50% of drug content was protected from premature release. In food simulants, the gallic acid release from nanoparticles was prolonged and sustained. Moreover, the nanoencapsulation did not reduce the antioxidant activity of gallic acid.Novelty and scientific contributionThe results show the importance of PEG in the formation and its effect on the properties of zein nanoparticles obtained by the liquid-liquid dispersion method. This study indicates that PEG-stabilized zein nanoparticles are potential carriers for oral intake of gallic acid, preserving its antioxidant properties and enabling its use in the pharmaceutical and food industries.

Gallic acid-loaded microemulsion and microemulsion gel: Development, characterization, and evaluation of antioxidant effectiveness

In this study, it was aimed to develop, characterize, and improve the antioxidant activity of gallic acid (GA) by formulating it into microemulsion (ME) and microemulsion gel (MEg). Blank MEs were prepared using different proportions of oil/water/surfactant, which provide stable and transparent ME production. Their droplet sizes, zeta potentials and stabilities after holding, centrifugation, and freeze-thawing processes were determined. F2 and F5 coded MEs were selected among the blank MEs and GA was loaded into these formulations. Besides the characterization studies, pH and viscosity measurement, in vitro release, cytotoxicity test, cell permeation, and antioxidant activity studies were performed. In vitro released amount of GA was enhanced by formulating it into ME and MEg at the end of six hours and it showed a scavenging effect of DPPH ● and ABTS ●+ radicals. In conclusion, increased efficacy, reduced toxicity, and prolonged antioxidant activity have been achieved with the use of new, non-toxic, and stable ME and MEg loaded with GA and it is thought that these formulations create the potential for topical application.

3,4,5-trihydroxycyclohexyl methanol - a new reduced derivative from structural activity relationship studies (SARS) on gallic acid

Gallic acid or 3,4,5-trihydroxybenzoic acid is a poly-hydroxyl compound with potential therapeutic effects in the treatment/management of oxidative stress implicated in cancers, cardiovascular and neurodegenerative diseases amongst many others. The identity, purity, integrity and suitability of the acid were ascertained and established prior to the preparation of derivatives. Furthermore, a simple titrimetric method for its assay was designed. The esterification and selective reduction of the acid led to two derivatives coded ME and MA whose identities have been established to be ethyl gallate and 3,4,5-trihydroxycyclohexylmethanol (possibly a new reduction derivative) respectively using the IR spectral technique. Gallic acid and MA demonstrated minimal antioxidant activity at IC 50 of 0.76 and 0.89 µg mL -1 , respectively. However, ME was remarkably active at 0.37 µg mL -1 which compare favourably with 0.34 µg mL -1 elicited by Vitamin C (a standard antioxidant drug). The obtained results indicate that esterification enhances the antioxidant activity of gallic acid.

PENENTUAN KADAR FENOLAT TOTAL DAN AKTIVITAS ANTIOKSIDAN DARI EKSTRAK DAUN DADAP MERAH (Erythrina fusca Lour) SECARA SPEKTROFOTOMETRI UV-Vis

Determination of total phenolate and antioxidant activity of red leaf extract (Erythrina fusca Lour) was done by UV-Vis spectrophotometry. This study aims to determine the total phenolic content and antioxidant activity of hexane, ethyl acetate and ethanol extract. The extracts were prepared using a non-polar-maseration method with hexane, ethyl acetate and ethanol solvents. The results showed total phenolic concentration using the Folin-Ciocalteu method were 0.412 g/100 g in the hexane extract, 1.782 g/100 g in the ethyl acetate extract and 5.455 g/100 g in the ethanol extract. Antioxidant activity conducted by using FRAP method (Ferric Reducing Antioxidant Power) were obtained 0,682 mmol Fe (II)/100 g at hexane extract, 5,186 mmol Fe (II)/100 g at ethyl acetate extract and 10,591 mmol Fe (II)/100 g on the ethanol extract. The antioxidant activity of gallic acid as standard was 44.356 g mmol Fe (II)/100g.

PENENTUAN KADAR FENOLAT TOTAL DAN AKTIVITAS ANTIOKSIDAN DARI EKSTRAK DAUN DADAP MERAH (Erythrina fusca Lour) SECARA SPEKTROFOTOMETRI UV-Vis

Determination of total phenolate and antioxidant activity of red leaf extract (Erythrina fusca Lour) was done by UV-Vis spectrophotometry. This study aims to determine the total phenolic content and antioxidant activity of hexane, ethyl acetate and ethanol extract. The extracts were prepared using a non-polar-maseration method with hexane, ethyl acetate and ethanol solvents. The results showed total phenolic concentration using the Folin-Ciocalteu method were 0.412 g/100 g in the hexane extract, 1.782 g/100 g in the ethyl acetate extract and 5.455 g/100 g in the ethanol extract. Antioxidant activity conducted by using FRAP method (Ferric Reducing Antioxidant Power) were obtained 0,682 mmol Fe (II)/100 g at hexane extract, 5,186 mmol Fe (II)/100 g at ethyl acetate extract and 10,591 mmol Fe (II)/100 g on the ethanol extract. The antioxidant activity of gallic acid as standard was 44.356 g mmol Fe (II)/100g.

Antioxidant Activity of Gallic Acid as Affected by an Extra Carboxyl Group than Pyrogallol in Various Oxidative Environments

Antioxidant Activity of Gallic Acid as Affected by an Extra Carboxyl Group than Pyrogallol in Various Oxidative Environments

How does the presence of an oxyradical influence the behavior of polyphenolic antioxidant? A case study on gallic acid.

Polyphenolic antioxidants are an integral component of the present-day lifestyle due to growing environmental and pollution-related issues. Gallic acid (GA), a popular polyphenolic antioxidant, is widely distributed in different fruits and vegetables. It scavenges free radicals mostly through the hydrogen atom transfer (HAT) mechanism. The present work reports a fundamental understanding of the atom transfer involved in the antioxidant activity of GA in the presence of prototype oxyradicals. In this article, the behavior of GA in the presence of three prototype oxyradicals, based on the availability in biological systems, viz. hydroxyl (•OH), hydroperoxyl (•OOH), and methyl peroxyl (•OOMe) is studied. On radical scavenging, a sharp change in the structural, electronic, and thermodynamic properties of GA is observed. Finally, a new descriptor based on chemical hardness, which describes the stability of the antioxidant molecule during a HAT reaction, is also proposed. Graphical abstract The present work reports a fundamental understanding of the atom transfer involved in antioxidant activity of gallic acid in presence of prototype oxyradicals.

Modulating the interfacial concentration of gallates to improve the oxidative stability of fish oil-in-water emulsions

Distributions of a homologous series of gallic acid (GA) derivatives of increasing lipophilicity were determined in stripped fish oil-in-water emulsions. The distribution was determined by employing a kinetic method based on the reaction between the hydrophobic 4-hexadecylbenzenediazonium ions (16-ArN2+) and the antioxidants (AOs), that allows to determine the partition constants between the oil-interfacial, POI, and water-interfacial, PWI, regions of the emulsion. Results showed that the antioxidant activity of gallic acid and its derivatives was positively correlated with the percentage of AO at the interface. The percentage of butyl, octyl and dodecyl gallates in the interfacial region is similar but much higher than that of the other derivatives, showing the highest AO efficiency. When increasing the surfactant fraction, the percentage of all compounds at the interface increased but the emulsion stability decreased due to the dilution of AO at the interface region. Both butyl and octyl gallates were found the most suitable AOs to carry out fish oil-in-water emulsions protection. For maximum effectiveness, butyl and octyl gallate should be used with the lowest emulsifier volume fraction necessary to physically stabilize emulsions.

GALLIC ACID FROM PODS OF JIRINGA (ARCHIDENDRON JIRINGA [JACK] I.C. NIELSEN) AND ITS ANTIOXIDANT

Objective: This study was aimed to isolate and investigate antioxidant activity of gallic acid in pods of jiringa (Archidendron jiringa [Jack] I.C. Nielsen).Methods: Pods of jiringa were extracted by maceration. Phenolic compounds were tested using FeCl3. Identification of pure compound was obtained from spectra data from nuclear magnetic resonance of proton H (1H NMR), NMR of carbon (13C NMR), infra-red, and mass spectrometry. Antioxidant activity was investigated using 1,1-diphenyl-2-picrylhydrazyl method.Results: The IC50 of gallic acid from jiringa’s pods (A. jiringa [Jack] I.C. Nielsen) was 3.65 μg/ml. This value showed that gallic acid from jiringa’s pods (A. jiringa [Jack] I.C. Nielsen) had high antioxidant activity.Conclusions: Gallic acid presents in pods of jiringa (A. jiringa [Jack] I.C. Nielsen) and has high antioxidant activity.

Polyphenols of Salix aegyptiaca modulate the activities of drug metabolizing and antioxidant enzymes, and level of lipid peroxidation

BackgroundSalix aegyptiaca is known for its medicinal properties mainly due to the presence of salicylate compounds. However, it also contains other beneficial phytochemicals such as gallic acid, quercetin, rutin and vanillin. The aim of the study was to examine the redox potential, antioxidant and anti-inflammatory activity of these phytochemicals along with acetylsalicylic acid.MethodsThe redox potential and antioxidant activity of gallic acid, quercetin, rutin, vanillin and acetylsalicylic acid were determined by oxidation-reduction potential electrode method and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, respectively. In ex vivo studies, antioxidant activity of these phytochemicals was determined by lipid peroxidation and carbonyl content assay in the liver of mice. Anti-inflammatory activity was determined by protein denaturation method. Six-week old C57BL/6 mice treated with gallic acid (100 mg/kg body weight) and acetylsalicylic acid (25 and 50 mg/kg body weight) to investigate their in vivo modulatory effects on the specific activities of drug metabolizing phase I and phase II enzymes, antioxidant enzymes and level of lipid peroxidation in liver.ResultsThe order of ability to donate electron and antioxidant activity was found to be: gallic acid > quercetin > rutin > vanillin > acetylsalicylic acid. In ex vivo studies, the similar pattern and magnitude of inhibitory effects of these phytochemicals against peroxidative damage in microsomes and protein carbonyl in cytosolic fraction were observed. In in vivo studies, gallic acid and acetylsalicylic acid alone or in combination, enhanced the specific activities of drug metabolizing phase I and phase II enzymes as well as antioxidant enzymes and also inhibited lipid peroxidation in liver.ConclusionsThese findings show a close link between the electron donation and antioxidation potential of these phytochemicals, and in turn their biological activity. Gallic acid, quercetin, rutin and vanillin were found to be better electron donors and antioxidants and therefore, might be mainly responsible for the antioxidant properties of S. aegyptiaca, while acetylsalicylic acid provided its maximum anti-inflammatory activity.

Influence of intrinsic and extrinsic factors on the antiradical activity of Gallic acid: a theoretical study

The factors responsible for the potent antioxidant activity of gallic acid (GA) are explored by employing density functional theory (DFT). It is found that the intrinsic characteristic features of the molecule play a significant role in its overall effectiveness as an antioxidant. The arrangement of the three hydroxyl groups with respect to each other imparts efficient antioxidant and antiradical property to GA. The external factors, such as polarity and pH of the reaction medium, also have a significant role to play. The polarity of the medium substantially affects the electron donating ability of GA, whereas the hydrogen atom donating ability is only marginally influenced. GA is a poor electron donor, but it can efficiently donate the hydrogen atom from its para hydroxyl group and effectively quench free radicals. It proves to be a better antiradical agent at the physiological pH, wherein it exists in the monoanionic form. Further, a comparison with other phenolic acids substantiates the importance of the carboxyl and hydroxyl groups in the antiradical activity of GA.

Post-Stroke Depression Modulation and in Vivo Antioxidant Activity of Gallic Acid and Its Synthetic Derivatives in a Murine Model System.

Gallic acid (3,4,5-trihydroxybenzoic acid, GA) is a plant secondary metabolite, which shows antioxidant activity and is commonly found in many plant-based foods and beverages. Recent evidence suggests that oxidative stress contributes to the development of many human chronic diseases, including cardiovascular and neurodegenerative pathologies, metabolic syndrome, type 2 diabetes and cancer. GA and its derivative, methyl-3-O-methyl gallate (M3OMG), possess physiological and pharmacological activities closely related to their antioxidant properties. This paper describes the antidepressive-like effects of intraperitoneal administration of GA and two synthetic analogues, M3OMG and P3OMG (propyl-3-O-methylgallate), in balb/c mice with post-stroke depression, a secondary form of depression that could be due to oxidative stress occurring during cerebral ischemia and the following reperfusion. Moreover, this study determined the in vivo antioxidant activity of these compounds through the evaluation of superoxide dismutase (SOD) and catalase (Cat) activity, thiobarbituric acid-reactive substances (TBARS) and reduced glutathione (GSH) levels in mouse brain. GA and its synthetic analogues were found to be active (at doses of 25 and 50 mg/kg) in the modulation of depressive symptoms and the reduction of oxidative stress, restoring normal behavior and, at least in part, antioxidant endogenous defenses, with M3OMG being the most active of these compounds. SOD, TBARS, and GSH all showed strong correlation with behavioral parameters, suggesting that oxidative stress is tightly linked to the pathological processes involved in stroke and PSD. As a whole, the obtained results show that the administration of GA, M3OMG and P3OMG induce a reduction in depressive symptoms and oxidative stress.

Encapsulation of gallic acid/cyclodextrin inclusion complex in electrospun polylactic acid nanofibers: Release behavior and antioxidant activity of gallic acid

Cyclodextrin-inclusion complexes (CD-ICs) possess great prominence in food and pharmaceutical industries due to their enhanced ability for stabilization of active compounds during processing, storage and usage. Here, CD-IC of gallic acid (GA) with hydroxypropyl-beta-cyclodextrin (GA/HPβCD-IC) was prepared and then incorporated into polylactic acid (PLA) nanofibers (PLA/GA/HPβCD-IC-NF) using electrospinning technique to observe the effect of CD-ICs in the release behavior of GA into three different mediums (water, 10% ethanol and 95% ethanol). The GA incorporated PLA nanofibers (PLA/GA-NFs) were served as control. Phase solubility studies showed an enhanced solubility of GA with increasing amount of HPβCD. The detailed characterization techniques (XRD, TGA and 1H-NMR) confirmed the formation of inclusion complex between GA and HPβCD. Computational modeling studies indicated that the GA made an efficient complex with HPβCD at 1:1 either in vacuum or aqueous system. SEM images revealed the bead-free and uniform morphology of PLA/GA/HPβCD-IC-NF. The release studies of GA from PLA/GA/HPβCD-IC-NF and PLA/GA-NF were carried out in water, 10% ethanol and 95% ethanol, and the findings revealed that PLA/GA/HPβCD-IC-NF has released much more amount of GA in water and 10% ethanol system when compared to PLA/GA-NF. In addition, GA was released slowly from PLA/GA/HPβCD-IC-NF into 95% ethanol when compared to PLA/GA-NF. It was also observed that electrospinning process had no negative effect on the antioxidant activity of GA when GA was incorporated in PLA nanofibers.

Antioxidant activity of alkyl gallates and glycosyl alkyl gallates in fish oil in water emulsions: Relevance of their surface active properties and of the type of emulsifier

The antioxidant activity of gallic acid and a series of alkyl gallates (C4–C18) and glycosylated alkyl gallates (C4–C18) on fish oil-in-water emulsions was studied. Three types of emulsifiers, lecithin, Tween-20 and sodium dodecyl sulphate (SDS) were tested. A nonlinear behavior of the antioxidant activity of alkyl gallates when increasing alkyl chain length was observed for emulsions prepared with lecithin. Medium-size alkyl gallates (C6–C12) were the best antioxidants. In contrast, for emulsions prepared with Tween-20, the antioxidants seem to follow the polar paradox. Glucosyl alkyl gallates were shown previously to be better surfactants than alkyl gallates. Nevertheless, they exhibited a worse antioxidant capacity than their corresponding alkyl gallates, in emulsions prepared with lecithin or Tween-20, indicating the greater relevance of having three OH groups at the polar head in comparison with having improved surfactant properties but just a di-ortho phenolic structure in the antioxidant.

Antioxidant activity of gallic acid and methyl gallate in triacylglycerols of Kilka fish oil and its oil-in-water emulsion

The anti-DPPH radical effect as well as anti-peroxide activity of gallic acid, methyl gallate, and α-tocopherol in a bulk Kilka fish oil and its oil-in-water emulsion stabilized by soy protein isolate at 55°C were investigated. Gallic acid with the lowest hydrophobicity (log P=−0.28) was found to be the most active antiradical agent (IC50=29.5μM), followed by methyl gallate (IC50=38.0μM, log P=−0.23) and α-tocopherol (IC50=105.3μM, log P=0.70). The anti-peroxide activity in the bulk oil system decreased in the order of methyl gallate>gallic acid>α-tocopherol. In the emulsion system, methyl gallate still behaved better than gallic acid, but the highest activity belonged to α-tocopherol. Based on the calculation of a number of kinetic parameters, the antioxidants, in general, showed better performances in the bulk oil system than in the emulsion system.

Investigation on Anticataract Activity of Triphala Ghrita

Lab prepared Triphala ghrita was studied for its possible anticataract activity on galactose induced cataract in Swiss albino rats. Administration of Triphala ghrita at a dose of 216 mg/200 g, 1080 mg/200 g and 2160 mg/200 g of rat orally offered significant dose dependent protection against galactose induced cataract and delayed the onset and progression of cataract. It was seen that the dose of 1080 mg of Triphala ghrita did not show stage II cataract in 14 days and stage III in 21 days. It did not show even stage III and stage IV cataract after 30 days whereas group B and group C showed stage III and stage IV cataracts. Dose of 2160 mg did not showed stage IV cataract after 30 days but showed stage III cataract. Dose of 1080 mg of Triphala ghrita offered significant protection against delaying the onset and progression of cataract in comparison to other doses. This effect may be attributed to the antioxidant activity of gallic acid, ellagic acid and ascorbic acid which shows their presence in Triphala ghrita. This preliminary study was encouraging but further studies are required to extrapolate the clinical usefulness of this formulation.

ANTIOXIDANT ACTIVITY OF WHITE WINE EXTRACTS AND SOME PHENOLIC ACIDS TOWARD CORN OIL OXIDATION

ABSTRACT The ability of white wine extracts and some phenolic acids to inhibit corn oil oxidation was evaluated by monitoring the absorbance at 234 nm and the p-anisidine value. Wine extracts, each at 120 mg/L total phenolics, were tested in corn oil stripped of tocopherols kept at 50C. Two extracts rich in phenolic acids significantly inhibited oil oxidation, the most active being equivalent to butylated hydroxyanisol (BHA) at 200 mg/L. Moreover, four phenolic acids were tested in corn oil stripped of tocopherols kept at 50C and in edible corn oil kept at 110C. Gallic acid and caffeic acid, each at 80 mg/L, appeared to be stronger antioxidants than BHA at 200 mg/L. The present results indicate that some white wine phenolics, such as phenolic acids, may be strong antioxidants in corn oil. Moreover, the antioxidant activity of gallic acid and caffeic acid indicates their potential application in corn oil. PRACTICAL APPLICATIONS The antioxidant activity of white wine phenolic extracts toward corn oil oxidation and the characterization of active phenolic compounds may be useful in developing nutrient antioxidants for corn oil. Moreover, the antioxidant activity of gallic acid and caffeic acid indicates their potential application in corn oil.

Antioxidant activity of gallic acid from rose flowers in senescence accelerated mice

The activities of the antioxidant enzymes catalase (CAT) and glutathione peroxidase (GPx) in the blood and liver of the aging model induced by injection of different doses of D-gal into normal mice, and in senescence accelerated mice (SAM) of different ages, were determined. The results showed that the enzyme activities in the D-gal treated mice did not alter appreciably but the enzyme activities in blood of the SAM declined significantly with the increase in age, especially in the 9-month-old SAM. When gallic acid purified from rose flowers was used to treat the 9-month-old male SAM, it not only reinstated the activities of CAT and GPx but also significantly reduced the amount of malondialdehyde (MDA) in the liver, brain and kidney. The results demonstrated that 9-month-old male SAM represent an appropriate animal model to evaluate the antioxidant activities of natural products.