The qualitative analysis of the green tea extract using ESI-MS method

Savić, Ivan; Nikolić, Vesna; Savić, Ivana; Nikolić, Ljubiša; Jović, Marko D.; Jović, Maja D.

doi:10.5937/savteh1401030s

Cited by 18 publications

(12 citation statements)

References 42 publications

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“…Peaks 12 and 13 were identified as kaempferol derivatives. For instance, Peak 12 (Rt = 31.95 min) shows a negative molecular ion peak [M − H] − at m / z 593.1487, and it was identified as kaempferol-3- O -rutinoside ( 12 ) [ 29 ]; and peak 13 (Rt = 32.22 min), which shows a negative molecular ion peak [M − H] − at m / z 447.0917, was identified as kaempferol-3- O -hexoside ( 13 ) [ 30 ]. Fragmentation for both molecules show the loss of glycosides generating signals that correspond to kaempferol ( m / z 284 and 285), as shown in Figure 8 .…”

Section: Resultsmentioning

confidence: 99%

Flavonoids and Ellagitannins Characterization, Antioxidant and Cytotoxic Activities of Phyllanthus acuminatus Vahl

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Arnáez

et al. 2017

Plants

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The phenolic composition of leaves from Phyllanthus acuminatus L., a plant commonly used in Costa Rica as traditional medicine, was studied using UPLC-ESI-MS on an enriched phenolic extract. A total of 20 phenolic compounds were identified, comprising eight flavonoids (two flavanones—pinocembrin isomers and six derivatives from apigenin, chrysin, quercetin, and kaempferol); seven ellagitannins, two flavan-3-ols (prodelphinidin B dimer and (epi)gallocatechin); and three phenolic acids (ellagic acid, trimethylellagic acid, and ferulic acid). All of these compounds are reported for the first time in P. acuminatus, while previously reported in the genus Phyllanthus. Antioxidant evaluation was performed for P. acuminatus phenolic extract obtaining DPPH results with a remarkably low IC50 value of 0.15 μg/mL. Also, cytotoxicity on gastric AGS and colon SW20 adenocarcinoma cell lines was evaluated, and highly promising results were obtained, with IC50 values of 11.3 μg/mL and 10.5 μg/mL, respectively. Furthermore, selectivity index values obtained when comparing cytotoxicity on normal Vero cells was SI > 20 for both cancer cell lines, indicating a particularly high selectivity. Additionally, Justicidin B, a metabolite extensively studied for its antitumoral activity, was isolated from a non-polar extract of P. acuminatus, and comparatively evaluated for both bioactivities. The DPPH value obtained for Justicidin B was moderate (IC50 = 14.28 μg/mL), while cytotoxicity values for both AGS (IC50 = 19.5 μg/mL) and SW620 (IC50 = 24.8 μg/mL) cell lines, as well as selectivity when compared with normal Vero cells (SI = 5.4 and 4.2 respectively), was good, but lower than P. acuminatus extract. These preliminary results suggest that P. acuminatus enriched phenolic extract containing flavonoids, ellagitannins, flavan-3-ols, and phenolic acids, reported for the first time in this plant, could be of interest for further cancer cytotoxicity studies to elucidate structure–bioactivity relationships, and the molecular mechanisms and pathways.

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Section: Resultsmentioning

confidence: 99%

Flavonoids and Ellagitannins Characterization, Antioxidant and Cytotoxic Activities of Phyllanthus acuminatus Vahl

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Moreira

Arnáez

et al. 2017

Plants

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“…In similitude to the increase in patronage and consumption, a lot of research is on-going on the nutritional composition as well as the health benefits associated with the consumption of same (Khan and Mukhtar 2007;Shi et al 2011). Therapeutically, tea has been studied due to its richness in phenolic compounds and its acclaimed health benefits to the neglect of other vital constituents such as proteins, carbohydrates and oils (Savić et al 2014;Zaveri 2006). The frequency and quantity of waste generated in the form of residue (after infusion of tea leaves) from the tea industry is high (Zhang et al 2014), extensively unexploited and uncharacterized.…”

Section: Introductionmentioning

confidence: 99%

Influence of ultrasound pretreatment on enzymolysis kinetics and thermodynamics of sodium hydroxide extracted proteins from tea residue

Ayim

Alenyorege

et al. 2018

J Food Sci Technol

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The effect of ultrasound pretreatment using Single Frequency Counter Current Ultrasound (SFCCU) on the enzymolysis of tea residue protein (TRP) extracted with sodium hydroxide was investigated. The concentration of TRP hydrolysate, enzymolysis kinetics and thermodynamic parameters after SFCCU pretreatment were determined and compared with traditional enzymolysis. The results indicated that both ultrasound assisted and traditional enzymolysis conformed to first-order kinetics within the limits of the studied parameters. Temperature and sonication had affirmative effect on the enzymolysis of TRP with temperature yielding greater impact. Michaelis constant ( ) in ultrasonic pretreated enzymolysis decreased by 32.7% over the traditional enzymolysis. The highest polypeptide concentration of 24.12 mg ml was obtained with the lowest energy requirement at improved conditions of 50 g L of TRP, alcalase concentration of 2000 U g, time of 10 min and temperature of 50 °C for the ultrasonic treated enzymolysis. The values of reaction rate constant () for TRP enzymolysis increased by 78, 40, 82 and 60% at 20, 30, 40 and 50 °C, respectively. The thermodynamic properties comprising activation energy (), change in enthalpy ) and entropy) were reduced by ultrasound pretreatment whereas Gibbs free energy ) was increased.

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“…The following conditions were identified as optimal: pH 2.8, confirmed the identity of all eluted analytes and their elution order on the C 8 column. Identification of analytes was performed by comparing our mass spectral data with the literature (Fabre, Rustan, de Hoffmann, & Quetin-Leclerc, 2001;March et al, 2006;Plazonic et al, 2009;Savic, Savic-Gajic, & Jovic, 2014).…”

Section: Optimization Of the Hplc Methodsmentioning

confidence: 99%

Statistical optimization of an RP‐HPLC method for the determination of selected flavonoids in berry juices and evaluation of their antioxidant activities

Ćirić

Jelikić-Stankov

Cvijović

et al. 2017

Biomedical Chromatography

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An isocratic RP-HPLC method for the separation and identification of selected flavonoids (quercetin, rutin, luteolin-7-O-glucoside, kaempferol and kaempferol-3-O-glucoside) in commercial berry juices (blackcurrant, blueberry, red raspberry and cherry) was developed with the aid of central composite design and response surface methodology. The optimal separation conditions were a mobile phase of 85:15 (% v/v) water-acetonitrile, pH 2.8 (adjusted with formic acid), flow rate 0.5 mL min and column temperature 35°C. The obtained levels of bioflavonoids (mg per 100 mL of juice) were as follows: for quercetin, ca. 0.21-5.12; for kaempferol, ca. 0.05-1.2; for rutin, ca. 0.4-6.5; for luteolin-7-O-glucoside, ca. 5.6-10.2; and for kaempferol-3-O-glucoside, ca. 0.02-0.12. These are considerably lower than the values in fresh fruits. Total phenolic, flavonoid and anthocyanin contents were determined spectrophotometrically. Total flavonoid content varied as follows: blackcurrant > blueberry > red raspberry > cherry. The antioxidant activity of juice extracts (DPPH and ABTS methods) expressed as IC values varied from 8.56 to 14.05 mg L . These values are ~2.5-3 times lower than quercetin, ascorbic acid and Trolox®, but compared with rutin and butylhydroxytoluene, berries show similar or better antioxidant activity by both the DPPH and ABTS methods.

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The qualitative analysis of the green tea extract using ESI-MS method

Cited by 18 publications

References 42 publications

Flavonoids and Ellagitannins Characterization, Antioxidant and Cytotoxic Activities of Phyllanthus acuminatus Vahl

Flavonoids and Ellagitannins Characterization, Antioxidant and Cytotoxic Activities of Phyllanthus acuminatus Vahl

Influence of ultrasound pretreatment on enzymolysis kinetics and thermodynamics of sodium hydroxide extracted proteins from tea residue

Statistical optimization of an RP‐HPLC method for the determination of selected flavonoids in berry juices and evaluation of their antioxidant activities

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