Antioxidant and free radical-scavenging properties of ethanolic extracts of defatted borage (Borago officinalis L.) seeds

1999 ◽  
Vol 67 (4) ◽  
pp. 399-414 ◽  
Author(s):  
Mahinda Wettasinghe ◽  
Fereidoon Shahidi
2008 ◽  
Vol 51 (6) ◽  
pp. 1225-1232 ◽  
Author(s):  
Lilian Regina Barros Mariutti ◽  
Gisela Pizarro de Mattos Barreto ◽  
Neura Bragagnolo ◽  
Adriana Zerlotti Mercadante

Ethanolic extracts from 23 different dried herbs and spices commercialized in Brazil were investigated for their free radical scavenging properties using the stable free radicals 2,2'-diphenyl-β-picrylhydrazyl (DPPH•) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS•+), and Trolox as reference (TEAC) for both radicals. The kinetic curves for both radicals showed to follow the first order kinetics model and the decay rate constant (k obs) was calculated. For all the samples, the two methods showed a good linear TEAC correlation, indicating that the average reactivity of the compounds present in the ethanolic extracts was similar. Sage and rosemary extracts showed the highest free radical scavenging capacities, while onion showed negligible activity and colorifico, one of the most consumed spices in Brazil, showed low ABTS•+ scavenging activity. Three distinct situations were found for the extracts concerning the DPPH• scavenging capacities: (1) extracts, like rosemary and laurel, that presented the same efficient concentrations (EC50 ) but differed in the TEAC values and velocities of action (k obs), (2) extracts, such as garlic and basil, that showed similar EC50 and TEAC values, but different k obs values and (3) extracts that reacted at the same velocities but completely differed in the free radical scavenging capacities, like black pepper, savory, nutmeg, rosemary and sage. Similar considerations could be done for the ABTS•+ results. For the first time the ABTS•+ scavenging activity for allspice, basil, cardamom, chives, colorifico, cumin, dill, laurel, marjoram, parsley and tarragon was reported.


Medicina ◽  
2008 ◽  
Vol 44 (9) ◽  
pp. 706 ◽  
Author(s):  
Jurga Bernatonienė ◽  
Rūta Masteikova ◽  
Daiva Majienė ◽  
Arūnas Savickas ◽  
Egidijus Kėvelaitis ◽  
...  

The aim of this study was to investigate antiradical activity of aqueous and ethanolic hawthorn fruit extracts, their flavonoids, and flavonoid combinations. Material and methods. Total amount of phenolic compounds and the constituents of flavonoids were determined using a high-performance liquid chromatography. The antioxidant activity of Crataegus monogyna extracts and flavonoids (chlorogenic acid, hyperoside, rutin, quercetin, vitexin-2O-rhamnoside, epicatechin, catechin, and procyanidin B2) quantitatively was determined using the method of spectrophotometry (diphenyl-1-picrylhydrazyl (DPPH·) radical scavenging assay and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid)(ABTS·+) radical cation decolorization assay). The level of tyrosine nitration inhibition was determined using a highperformance liquid chromatography. Results. Ethanolic hawthorn fruit extract contained 182±4 mg/100 mL phenolic compounds, i.e. threefold more, as compared to aqueous extract. The antioxidant activity according to DPPH· reduction in the ethanolic extracts was higher 2.3 times (P<0.05). The ABTS·+ technique showed that the effect of ethanolic extracts was by 2.5 times stronger than that of aqueous extracts. Tyrosine nitration inhibition test showed that the effect of ethanolic extracts was by 1.4 times stronger than that of aqueous extracts. The investigation of the antiradical activity of the active constituents in aqueous and ethanolic extracts revealed that epicatechin and catechin contribute to radical-scavenging properties more than other components. Procyanidin B2 only insignificantly influenced the antiradical activity of the extracts. Conclusion. Both aqueous and ethanolic hawthorn extracts had antiradical activity, but ethanolic extract had stronger free radical-scavenging properties, compared to the aqueous extract. The antioxidant activity of the studied preparations was mostly conditioned by epicatechin and catechin. The individual constituents of both extracts had weaker free radical-scavenging properties than the combination of these substances did.


Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4169
Author(s):  
Nuntouchaporn Hutachok ◽  
Pimpisid Koonyosying ◽  
Tanachai Pankasemsuk ◽  
Pongsak Angkasith ◽  
Chaiwat Chumpun ◽  
...  

We aimed to analyze the chemical compositions in Arabica coffee bean extracts, assess the relevant antioxidant and iron-chelating activities in coffee extracts and instant coffee, and evaluate the toxicity in roasted coffee. Coffee beans were extracted using boiling, drip-filtered and espresso brewing methods. Certain phenolics were investigated including trigonelline, caffeic acid and their derivatives, gallic acid, epicatechin, chlorogenic acid (CGA) and their derivatives, p-coumaroylquinic acid, p-coumaroyl glucoside, the rutin and syringic acid that exist in green and roasted coffee extracts, along with dimethoxycinnamic acid, caffeoylarbutin and cymaroside that may be present in green coffee bean extracts. Different phytochemicals were also detected in all of the coffee extracts. Roasted coffee extracts and instant coffees exhibited free-radical scavenging properties in a dose-dependent manner, for which drip coffee was observed to be the most effective (p < 0.05). All coffee extracts, instant coffee varieties and CGA could effectively bind ferric ion in a concentration-dependent manner resulting in an iron-bound complex. Roasted coffee extracts were neither toxic to normal mononuclear cells nor breast cancer cells. The findings indicate that phenolics, particularly CGA, could effectively contribute to the iron-chelating and free-radical scavenging properties observed in coffee brews. Thus, coffee may possess high pharmacological value and could be utilized as a health beverage.


2009 ◽  
Vol 114 (1) ◽  
pp. 276-281 ◽  
Author(s):  
Ilkay Orhan ◽  
Murat Kartal ◽  
Mahmoud Abu-Asaker ◽  
F. Sezer Şenol ◽  
Gülderen Yilmaz ◽  
...  

2013 ◽  
Vol 141 (1) ◽  
pp. 153-159 ◽  
Author(s):  
Rong He ◽  
Adeola Alashi ◽  
Sunday A. Malomo ◽  
Abraham T. Girgih ◽  
Dongfang Chao ◽  
...  

Author(s):  
Sethupandian Geetha ◽  
Kokkaiah Irulandi ◽  
Palanichamy Mehalingam

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


Author(s):  
Dakshayini P. N. ◽  
Mahaboob Basha P.

Objective: This study aimed to investigate the antioxidants and free radicals scavenging properties of ethanolic extracts from Tribulus terrestris fruit (TTF) and Mesua ferrea flower (MFF).Methods: The antioxidant and free radical scavenging activities were measured by using standard protocols against phytoextracts used at 50, 100, 150, 200 and 250 µg/ml concentration. Total phenolic and flavonoid content were estimated using Folin-Ciocalteu and aluminium-chloride reagent assay methods.Results: Among the extracts, MFF showed the highest total antioxidant ability followed by TTF. With regard to various scavenging activities, MFF had the highest radical scavenging activity than TTF extract closely resembled the standards. Also, the reducing capacity on ferrous ion was high in MFF than TTF. The quantified phenolic contents of TTF and MFF ethanolic extracts were 27.0±0.36 and 57.0±0.32 mg gallic acid equivalent per gram extract respectively. A positive correlation (p value<0.001) was observed between phenolic content and free radical scavenging efficiencies.Conclusion: The results confirm that both MFF and TTF are important sources of natural antioxidants and serves as an effective free radical scavengers and/or inhibitors. Hence, both extracts are suitable plant-based pharmaceutical products can be used to handle 'free radical-mediated diseases.


2010 ◽  
Vol 87 (6) ◽  
pp. 615-620 ◽  
Author(s):  
Jérôme Lecomte ◽  
Luis Javier López Giraldo ◽  
Mickaël Laguerre ◽  
Bruno Baréa ◽  
Pierre Villeneuve

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