scholarly journals Comparison of antioxidant activity and bioavailability of tea epicatechins with their epimers

2004 ◽  
Vol 91 (6) ◽  
pp. 873-881 ◽  
Author(s):  
Jin Ze Xu ◽  
Sai Ying Venus Yeung ◽  
Qi Chang ◽  
Yu Huang ◽  
Zhen-Yu Chen
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Green Tea ◽  
Ldl Oxidation ◽  
Preparative Hplc ◽  
Epicatechin Gallate ◽  
Frap Assay ◽  
Antioxidant Power ◽  
Isolation And Purification ◽  
Plasma Antioxidant Capacity

Canned and bottled tea drinks contain not only green tea epicatechins (GTE), namely (−)-epigallocatechin gallate (EGCG), (−)-epicatechin gallate (ECG), (−)-epigallocatechin (EGC) and (−)-epicatechin (EC), but also four GTE epimers, namely (−)-gallocatechin gallate (GCG), (−)-catechin gallate (CG), (−)-gallocatechin (GC) and (−)-catechin (C). In the present study we examined the antioxidant activity and bioavailability of these epimers compared with their corresponding precursors. The epimerisation reaction was induced by autoclaving GTE extract derived from longjing green tea at 120°C for 20 min. Isolation and purification of each GTE and epimer were accomplished by various column chromatographic and semi-preparative HPLC techniques. The antioxidant activity of each epimer with its corresponding GTE precursor was conducted in the three in vitro systems, namely human LDL oxidation, ferric reducing–antioxidant power (FRAP), and anti-2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical assays. The results of all three assays demonstrated that CG had similar antioxidant activity with its precursor ECG, while GC was less potent as an antioxidant than its precursor EGC. Regarding EGCG and GCG, the antioxidant potency was similar for both LDL oxidation and DPPH free radical assays, but GCG was statistically less effective than EGCG in the FRAP assay. For EC and C, the latter had less anti-free radical activity in the DPPH assay, but in LDL oxidation and FRAP assays the antioxidant activity was similar. Oral and intravenous dosing of GTE–epimer mixture led to increase in total plasma antioxidant capacity in rats. In general, both epicatechins and epimers had low bioavailability (0·08–0·31) and most of the observed differences between epicatechins and their corresponding epimers were small, even if they were statistically significant in some cases. It was concluded that the epimerisation reaction occurring in manufacturing canned and bottled tea drinks would not significantly affect antioxidant activity and bioavailability of total tea polyphenols.

Antioxidant and anticancer activities of an Aporphine alkaloid isolated from Alphonsea sclerocarp

2018 ◽  
Vol 7 (1) ◽  
pp. 51-55
Author(s):  
Suman Joshi DSD ◽  
◽  
Chander Amgoth ◽  
Surya Narayana S ◽  
Padmavathi CH ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Medicinal Plant ◽  
Chronic Myeloid Leukaemia ◽  
Mtt Assay ◽  
Preparative Hplc ◽  
Spectroscopic Techniques ◽  
Anticancer Activities ◽  
Frap Assay ◽  
Aporphine Alkaloid ◽  
Dose Dependent

Herein, we report on the anticancer and antioxidant activity of an Aporphine alkaloid isolated from medicinal plant Alphonsea sclerocarpa. Conventional column chromatography and preparative HPLC methods were used to isolate and purify the alkaloid. Based on NMR, FTIR and MS/MS spectroscopic techniques the compound was identified as Crebanine. This is the first report on the presence of Crebanine from the leaves of Alphonsea sclerocarpa. Antioxidant activity was evaluated using DPPH and FRAP assay. The antioxidant activity was dose-dependent and activity increased with the increase in the concentration. The cytotoxicity assay was carried out using MTT assay. The results showed remarkable cytotoxic activity against K562 (CML-chronic myeloid Leukaemia blood cancer) cells with a % inhibition of 37.545 at 500µm concentration after an incubation of 24h

scholarly journals EVALUATION OF ANTIOXIDANT AND FREE RADICAL SCAVENGING ACTIVITIES OF DIFFERENT SOLVENT EXTRACTS OF LEAVES OF PIPER UMBELLATUM

2017 ◽  
Vol 10 (2) ◽  
pp. 274
Author(s):  
Sethupandian Geetha ◽  
Kokkaiah Irulandi ◽  
Palanichamy Mehalingam
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Ethyl Acetate ◽  
Methanol Extract ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Reducing Power ◽  
Free Radical Scavenging ◽  
Frap Assay ◽  
Radical Scavenging Properties

Objective: This study was designed to determine the Total phenol, flavonoid content, antioxidant and free radical scavenging properties of different solvent extracts of Piper umbellatum.  Methods: Different solvent extracts evaluated with DPPH radical scavenging activity and Reducing power activity.Results: The presence of phenol and flavonoid showed highly in the methanol extracts than ethyl acetate and acetone extracts. All the extracts have various level of antioxidant activity. Methanol solvent extract have good extraction and show significant antioxidant activity. The effect of reducing power of methanol extract revealed good antioxidant activity compare with other tested extracts.Conclusion: On the basis of the above results we concluded that methanol extract of Piper umbellatum whole plant extracts shows significant antioxidant activity than ethyl acetate and acetone extracts.Keywords: Piper umbellatum, Antioxidant, DPPH, FRAP assay, Polar, Non polar solvents

scholarly journals COMPARISION OF ANTIOXIDANT ACTIVITY OF ACTINIDIA DELICIOSA AND PSIDIUM GUAJAVA USING FERRIC REDUCING ANTIOXIDANT POWER ASSAY METHOD

2020 ◽  
pp. 175-178
Author(s):  
CAROLINE JEBA R ◽  
INDHUJA D
Keyword(s):  
Antioxidant Activity ◽  
Room Temperature ◽  
Psidium Guajava ◽  
Actinidia Deliciosa ◽  
Assay Method ◽  
Frap Assay ◽  
Antioxidant Power ◽  
Hot Air ◽  
Ferric Reducing Antioxidant Power ◽  
Dried Extract

Objectives: Antioxidant activity was studied in naturally dried seed extract and hot air oven dried extract of Actinidia deliciosa and Psidium guajava using ferric reducing antioxidant power (FRAP) assay method. Methods: The dried powdered seed of A. deliciosa and P. guajava 10 g was dissolved in 100 ml of ethanol in four different conical flasks S1 (for naturaly dried seeds of A. deliciosa), S2 (for hot air oven-dried seeds of A. deliciosa), S3 (for naturally dried seeds of P. guajava), and S4 (for hot air oven-dried seeds of P. guajava). The extract was carried out in shaker at 120 rpm for 72 h at room temperature by mild shaking. The extract was taken out and centrifuged at 4000 rpm for 10 min, the supernatant was taken out. The supernatant was placed in a water bath at 95°C for the solvent to evaporate and stored at room temperature. Results: According to the FRAP results, P. guajava which was naturally dried and extracted has shown the highest antioxidant activity (sample 3) then followed by the samples S4, S1, and S2. The least activity is observed in the sample (S2). Conclusion: By comparing the antioxidant activity between the A. deliciosa and P. guajava with the help of FRAP assay results, P. guajava has the highest amount of vitamin C (responsible for antioxidant activity) when compared to that of the A. deliciosa.

Synthesis and Antioxidant Activity of Resin of Chitosan Cerium Encapsulated Green Tea Extract Microspheres

2011 ◽  
Vol 194-196 ◽  
pp. 734-741
Author(s):  
Li Na Yu ◽  
Dong Feng Wang ◽  
Qing Li Yang ◽  
Hai Yan Li ◽  
Bing Jie Liu ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Green Tea ◽  
Polyphenolic Compounds ◽  
Green Tea Extract ◽  
Emission Spectrometry ◽  
Narrow Particle Size Distribution ◽  
Human Beings ◽  
Free Radical Damage ◽  
Tea Extract

The purpose of this paper is to investigate a new type of resin of chitosan cerium encapsulated green tea extract microspheres (RCCM-GTE) prepared by the reversed-phase suspension cross-linking polymerization and study the scavenging activity against DPPH free radical. The results showed that RCCM-GTE was a type of deep brown-yellow spherical resin with smooth surface and it presented uniform and narrow particle size distribution as determined by the Laser Particles Sizer. The Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES), Fourier Transform Infrared Spectroscopy (FT-IR) and differential scanning calorimetry (DSC) study demonstrated that there was cerium existing in RCCM-GTE. The polyphenolic compounds existed in RCCM-GTE and the total content of polyphenolic compounds encapsulated in RCCM-GTE was found to be 92.550±1.145 μg/g. It is considered that the good antioxidant activity of RCCM-GTE was the comprehensive results of the action of tea polysaccharide-protein conjugate, polyphenolic compounds, cerium and Schiff base chitosan. Investigation showed that a lot of extracts coming from agriculture and food industry contain reactive components of polyphenolic compounds and polysaccharides. It can be effective in protection of human beings from free radical damage if these extracts are directly or after the extraction and purification added to food as natural food antioxidant or they are prepared micospheres reacted with some biopolymers through coordination as a health food. Then the emerging area of research on encapsulating GTE in chitosan cerium resin must have a broad developing prospect.

scholarly journals The Free Radical Scavenging and Anti-Isolated Human LDL Oxidation Activities of Pluchea indica (L.) Less. Tea Compared to Green Tea (Camellia sinensis)

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Kittipot Sirichaiwetchakoon ◽  
Gordon Matthew Lowe ◽  
Griangsak Eumkeb
Keyword(s):  
Free Radical ◽  
Green Tea ◽  
Camellia Sinensis ◽  
Hypochlorous Acid ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Free Radical Scavenging ◽  
Ldl Oxidation ◽  
Caffeoylquinic Acid ◽  
Dicaffeoylquinic Acid

Tea is one of the most popular beverages in the world. Camellia sinensis tea (CST) or green tea is widely regarded as a potent antioxidant. In Thailand, Pluchea indica (L.) Less. tea (PIT) has been commercially available as a health-promoting drink. This study focused on free radical scavenging activities of PIT, and its ability to protect isolated human low-density lipoproteins (LDL) from oxidation by chemical agents. A preliminary study to investigate the antioxidant nature of PIT was undertaken. These included common antioxidant assays involving 2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS), hypochlorous acid (HOCl), and its potential to scavenge peroxynitrite. In separated experiments, isolated human LDL was challenged with either 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH), copper (Cu2+), or 3-Morpholinosydnonimine hydrochloride (SIN-1) to induce LDL oxidation. PIT exhibited antioxidant activity in all test systems and performed significantly better than CST in both DPPH (P<0.05; IC50PIT=245.85±15.83 and CST=315.41±24.18 μg/ml) and peroxynitrite scavenging assays. PIT at 75 μg/ml almost fully prevented the peroxynitrite over a 5 h period. Moreover, it displayed similar properties to CST during the antioxidation of isolated human LDL using AAPH, Cu2+, SIN-1, and hypochlorous acid scavenging assays. However, it revealed a significantly lower ABTS scavenging activity than CST (P<0.05; IC50PIT=30.47±2.20 and CST=21.59±0.67 μg/ml). The main constituents of the PIT were identified using LC-MS/MS. It contained 4-O-caffeoylquinic acid (4-CQ), 5-O-caffeoylquinic acid (5-CQ), 3,4-O-dicaffeoylquinic acid (3,4-CQ), 3,5-O-dicaffeoylquinic acid (3,5-CQ), and 4,5-O-dicaffeoylquinic acid (4,5-CQ). In conclusion, caffeoyl derivatives in PIT could play an important role in potent antioxidant properties. So, it may be further developed to be antioxidant beverages for preventing atherosclerosis and cardiovascular diseases associated with oxidative stress.

scholarly journals ANTIOXIDANT ACTIVITIES OF FRACTIONS FROM ETHYL ACETATE EXTRACTS OF GARCINIA FRUTICOSA LAUTERB. LEAVES

2018 ◽  
Vol 10 (1) ◽  
pp. 44 ◽  
Author(s):  
Riza Shabrina ◽  
Berna Elya ◽  
Arikadia Noviani
Keyword(s):  
Antioxidant Activity ◽  
Ethyl Acetate ◽  
Antioxidant Activities ◽  
Radical Scavenging Activity ◽  
Group Identification ◽  
Radical Scavenging ◽  
Dpph Radical ◽  
Frap Assay ◽  
Antioxidant Power ◽  
Dpph Radical Scavenging

Objective: This study aimed to fractionate the antioxidant activity of the ethyl acetate leaf extract and to characterize the most active fractionsaccording to compound groups.Methods: The ethyl acetate extract was fractionated with column chromatography using a gradient elution system. Fractions were first screenedqualitatively for antioxidant activity before active fractions were quantified with respect to in vitro antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and the ferric-reducing antioxidant power (FRAP) assay. The compound groups were identifiedfollowing separation by thin-layer chromatography.Results: Fraction 11 exhibited the greatest DPPH radical-scavenging activity, with an IC50 value of 6.58 μg/mL, while the fraction with the greatestantioxidant activity according to the FRAP assay was fraction 10, with a ferric ion equivalent antioxidant activity value of 1015.34 μmol/g.Conclusion: Compound group identification revealed that Fractions 10 and 11 contained flavonoids, with two common to both fractions, whilefraction 10 also contained one specific flavonoid.

scholarly journals PENGARUH WAKTU FERMENTASI TERHADAP AKTIVITAS ANTIOKSIDAN DAN KADAR BETASIANIN MINUMAN FUNGSIONAL DARI BUAH NAGA (Hylocereus polyrhizus) DAN UMBI BIT (Beta vulgaris)

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Yati Maryati ◽  
Agustine Susilowati ◽  
Nina Artanti ◽  
Puspa Dewi Narij Lotulung ◽  
Aspiyanto Aspiyanto
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Antioxidant Activities ◽  
Iron Ions ◽  
Antioxidant Power ◽  
Fermentation Time ◽  
Reduction Of Iron ◽  
Dragon Fruit ◽  
Functional Beverages ◽  
Ferric Reducing Antioxidant Power

Effect of Fermentation on Antioxidant Activities and Betacyanin Content of Functional Beverages from Dragon Fruit and BeetrootKombucha is a traditional beverage prepared by fermenting polyphenol-rich tea using a consortium of bacteria and yeast (SCOBY). Dragon fruit and beetroot contain a significantly high amount of polyphenols and betacyanin as antioxidants which are beneficial in reducing the risk of cardiovascular disease, cancer, and the body's natural degeneration related to the early-aging process. This study aims to determine changes in antioxidant activity and levels of betacyanin from fermented dragon fruit and beetroot as functional drinks during different fermentation times. The results showed that there was a correlation between fermentation time and antioxidant activity in its ability to counteract free radicals, ferric reducing antioxidant power (FRAP), and the levels of betacyanin produced. Longer fermentation time caused an increase in free radical inhibition and reduction of iron ions but reduced the levels of betacyanin. The optimum value of free radical inhibitory activity (DPPH) was obtained in the 12-day fermented dragon fruit drink with an inhibitory value of 80.76%, ability to reduce iron ions by 197.94 µg ascorbic acid mL-1, and betacyanin level of 0.055 mg L-1Keywords: antioxidants, dragon fruit, betacyanin, beetroot, functional beverages ABSTRAKKombucha merupakan minuman tradisional hasil olahan fermentasi teh yang kaya polifenol dengan konsorsium bakteri dan yeast (SCOBY). Buah naga dan umbi bit memiliki polifenol dan senyawa betasianin yang cukup tinggi sebagai antioksidan yang bermanfaat dalam menurunkan risiko penyakit kardiovaskular, penyakit kanker dan degenerasi alami tubuh terkait proses penuaan dini. Penelitian ini bertujuan untuk mengetahui perubahan aktivitas antioksidan dan kadar betasianin dari fermentasi buah naga maupun umbi bit sebagai minuman fungsional selama waktu fermentasi yang berbeda. Hasil penelitian menunjukkan bahwa adanya korelasi antara waktu fermentasi terhadap aktivitas antioksidan dalam kemampuannya menangkal radikal bebas, kemampuan mereduksi ion besi (FRAP), dan kadar betasianin yang dihasilkan. Semakin lama waktu fermentasi menyebabkan peningkatan penghambatan radikal bebas dan reduksi ion besi, namun menurunkan kadar betasianin. Nilai aktivitas penghambatan radikal bebas (DPPH) optimum diperoleh dari minuman fermentasi buah naga selama waktu fermentasi 12 hari dengan nilai penghambatan sebesar 80,76%, kemampuannya dalam mereduksi ion besi sebesar 197,94 µg asam askorbat mL–1, dan kadar betasianin sebesar 0,055 mg L–1

scholarly journals EVALUASI SEDIAAN MASKER ANTIOKSIDAN DARI EKSTRAK DAUN TEH HIJAU (CAMELLIA SINENSIS)

2019 ◽  
Vol 10 (2) ◽  
pp. 119-128
Author(s):  
Desi Nawangsari
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Green Tea ◽  
Camellia Sinensis ◽  
Ethanol Extract ◽  
Tea Leaves ◽  
Strong Activity ◽  
Reduction Activity ◽  
Radical Reduction ◽  
Green Tea Leaves

Abstract Green tea (Camellia sinensis L.) has the main efficacy as an antioxidant and contains polyphenol compounds in green tea leaves with the main component of polyphenol fraction namely Epigallocatechin-3-gallate (EGCG) which has strong activity to prevent free radicals that cause premature aging. Research has been carried out on the formulation of maskantioxidant preparations containing green tea leaf extract. The study begins with testing the antioxidant activity of ethanol extract of green tea leaves with a free radical reduction method of 1,1-diphenyl-2-picrylhydrazyl using visible spectrophotometry. Testing of antioxidant activity showed that the ethanol extract of green tea leaves gave an IC50 value of 3.17µg / mL. Formulations of gel masks made were F0 (base without active substances), F1 (base + concentration of ethanol extract of green tea leaves for IC50 (0,000317%)), F2 (base + concentration of ethanol extract of green tea leaves for 50xIC50 (0, 0158%)), F3 (base + concentration of ethanol extract of green tea leaves for 100xIC50 (0.0317%)), F4 (base + concentration of ethanol extract of green tea leaves for IC50), F5 (base + concentration of ethanol extract of green tea leaves worth IC50), F6 (base + concentration of ethanol extract of green tea leaves for IC50. Evaluation of gel mask preparations include, organoleptic examination and homogeneity, pH, viscosity, dry time of preparation and testing of antioxidant stability. F2 provides better and higher free radical reduction activity than products on the market. F4, F5, F6 shows an increase in free radical reduction activity.   Keywords: Green tea leaves (Camellia sinensis L.), DPPh, IC50 gel mask.

scholarly journals UJI AKTIVITAS SEDIAAN MASKER ANTIOKSIDAN DARI EKSTRAK DAUN TEH HIJAU (CAMELLIA SINENSIS)

2019 ◽  
Vol 10 (2) ◽  
pp. 129-134
Author(s):  
Desi Nawangsari
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Green Tea ◽  
Camellia Sinensis ◽  
Ethanol Extract ◽  
Tea Leaves ◽  
Strong Activity ◽  
Reduction Activity ◽  
Radical Reduction ◽  
Green Tea Leaves

Abstract   Green tea (Camellia sinensis L.) has the main efficacy as an antioxidant and contains polyphenol compounds in green tea leaves with the main component of polyphenol fraction namely Epigallocatechin-3-gallate (EGCG) which has strong activity to prevent free radicals that cause premature aging. Research has been carried out on the formulation of maskantioxidant preparations containing green tea leaf extract. The study begins with testing the antioxidant activity of ethanol extract of green tea leaves with a free radical reduction method of 1,1-diphenyl-2-picrylhydrazyl using visible spectrophotometry. Testing of antioxidant activity showed that the ethanol extract of green tea leaves gave an IC50 value of 3.17µg / mL. Formulations of gel masks made were F0 (base without active substances), F1 (base + concentration of ethanol extract of green tea leaves for IC50 (0,000317%)), F2 (base + concentration of ethanol extract of green tea leaves for 50xIC50 (0, 0158%)), F3 (base + concentration of ethanol extract of green tea leaves for 100xIC50 (0.0317%)), F4 (base + concentration of ethanol extract of green tea leaves for IC50), F5 (base + concentration of ethanol extract of green tea leaves worth IC50), F6 (base + concentration of ethanol extract of green tea leaves for IC50. Evaluation of gel mask preparations include, organoleptic examination and homogeneity, pH, viscosity, dry time of preparation and testing of antioxidant stability. F2 provides better and higher free radical reduction activity than products on the market. F4, F5, F6 shows an increase in free radical reduction activity.   Keywords: Green tea leaves (Camellia sinensis L.), DPPh, IC50 gel mask.

scholarly journals Chemopreventative Potential of Plant-Based Extracts Coffee (Coffea) and Mauby (Colubrina Arborescens) using the Global Antioxidant Response (GAR) Method via in vitro Simulated Digestion

2021 ◽  
Vol 10 (3) ◽  
pp. 43
Author(s):  
Hannah Gross ◽  
Cheryl Rock ◽  
Yada Treesukosol ◽  
Virginia Gray
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Radical Scavenging ◽  
Reducing Power ◽  
Antioxidant Response ◽  
Free Radical Scavenging ◽  
Antioxidant Power ◽  
Simulated Digestion ◽  
Radical Scavenging Capacity ◽  
Scavenging Capacity

Plant-based extracts such as coffee (coffea) and Mauby (Colubrina Arborescens) were tested for chemopreventative potential by measuring their antioxidant activity (i.e., reducing power and free radical scavenging capacity) conventionally using chemical assays 1, 1-Diphenyl-2-picryl-hydrazyl (DPPH) and Ferric Reducing Antioxidant Power (FRAP). Alternately, extracts were also analyzed for their chemopreventative potential via a novel method (Global Antioxidant Response [GAR]), where they were subjected to simulated digestion before their antioxidant activity was determined via conventional methods previously mentioned. Next, the antioxidant capacities of the extracts, conventional versus the novel (GAR) method were compared. Overall, the analysis indicated that the reducing power (FRAP) and free radical scavenging capacity (DPPH) of coffee and Mauby were reduced (~16%) after undergoing simulated digestion. It was also observed that while the antioxidants in Mauby scavenged radicals at a significantly higher capacity than those in coffee (95.7% &plusmn; 0.67 and 90% &plusmn; 2.1 before digestion, and 77.7% &plusmn; 2.2 and 74.6% &plusmn; 2.3 after digestion, respectively), antioxidants in coffee exhibited higher reducing power compared to those in Mauby. Specifically, after undergoing simulated digestion, 1.12 mM FeSO4/mL &plusmn; 0.05 to 0.68 mM FeSO4/mL &plusmn; 0.07 ions were reduced before digestion, and 0.73 mM FeSO4/mL &plusmn; 0.09 to 0.48 mM FeSO4/mL &plusmn; 0.04 ions were reduced after digestion for coffee and Mauby, respectively. These findings suggest that while the antioxidants in coffee may have been more powerful in their ability to reduce ions, the antioxidants in Mauby may have been more effective in scavenging and neutralizing radicals.

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