Phenolic content and antioxidant activity of rooibos food ingredient extracts

Joubert, Elizabeth; Beer, Dalene de

doi:10.1016/j.jfca.2012.03.011

Cited by 49 publications

(53 citation statements)

References 24 publications

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“…The shoot (stem and leaves) of this plant is used to produce an herbal infusion (Rooibos tea) internationally ascribed with important health promoting properties [21], including the potential to lower glucose levels in animals [22]. The plant is a member of the legume family and indigenous to the Cederberg region, in the northwest of Cape Town, South Africa, where the local communities have been using it to brew tea for centuries.…”

Section: Desalination and Water Treatmentmentioning

confidence: 99%

Biosorption of Pb(II) from aqueous solution using Rooibos shoot powder (RSP)

Kanu

Moyo

Zvinowanda

et al. 2016

Desalination and Water Treatment

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A B S T R A C TRooibos (Aspalathus linearis) plants are cultivated for the production of the Rooibos tea. In this work, biosorption process of Pb(II) from aqueous solution on Rooibos shoot powder (RSP) was studied in a batch process. The effect of experimental parameters such as solution pH (2-9), contact time (30-180 min) and initial Pb(II) concentration (25-400 mg L −1 ), adsorbent dosage (0.2-2.1 g), and temperature (25-80˚C) on biosorption process was examined. In an attempt to determine the biosorption capacity and rate of Pb(II) removal, isotherm and kinetic data were modeled using different equations. To this end, the biosorption process by RSP followed the Langmuir model for Pb(II) ions (R 2 = 0.9907), with maximum monolayer adsorption capacity of 18.90 mg g −1 . Kinetic data were properly fitted with the pseudo-second order kinetic model, and it can be seen that the calculated q e (cal) value (11.31 mg g −1 ) agrees with the experimental value (12.80 mg g −1 ). Furthermore, the biosorbent showed good removal of Pb(II) from industrial wastewaters.

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Section: Desalination and Water Treatmentmentioning

confidence: 99%

Biosorption of Pb(II) from aqueous solution using Rooibos shoot powder (RSP)

Kanu

Moyo

Zvinowanda

et al. 2016

Desalination and Water Treatment

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“…The vitexin, isovitexin, orientin, and rhoifolin are efficient antioxidants. For example, the antioxidant activity of rhoifolin was measured using the oxygen radical absorbance capacity which is an acknowledged method for antioxidant assessment [23][24][25][26] . The anticancer and antiviral effect of J. curcas may then be related to vitexin, isovitexin, orientin and rhoifolin.…”

Section: Lc-dad-ms (Esi-) Analysis Of the Collected Fractionsmentioning

confidence: 99%

Antioxidant activity of flavonoids from leaves of Jatropha curcas

Huang¹,

Guo²,

Fu³

et al. 2014

ScienceAsia

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The objective of this study was to characterize the antioxidant properties of ethanol extracted from leaves of Jatropha curcas and to determinate the compounds. The IC 50 values of DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2 -azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt) were found to be 7.47 and 6.6 µg/ml, respectively, for the extracts. The reducing power of the extracts increased from 0.09 to 0.16, respectively, for 1-32 µg/ml of standard reagent. The assignment of the flavone compounds using HPLC-DAD-MS n was based on the evaluation of their UV-Vis absorption maxima (λmax) and mass spectral analyses. Tentatively, 4 compounds (orientin, vitexin, isovitexin, rhoifolin) were identified.

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“…*mg/mL content was calculated from the soluble solids [33], see Experimental, soluble solid values determined for green and fermented rooibos infusions were 1.0 and 0.8 mg/mL, respectively.…”

Section: Figurementioning

confidence: 99%

Anti-Peroxyl Radical Quality and Antibacterial Properties of Rooibos Infusions and Their Pure Glycosylated Polyphenolic Constituents

et al. 2013

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Abstract:The anti-peroxyl radical quality of two aqueous rooibos infusions and solutions of their most abundant glycosylated polyphenols was evaluated using pyrogallol red and fluorescein-based oxygen radical absorbance ratios. It was observed that the artificial infusions, prepared using only the most abundant polyphenols present in rooibos and at concentrations similar to those found in the natural infusions, showed greater antioxidant OPEN ACCESSMolecules 2013, 18 11265 quality than the latter infusions, reaching values close to those reported for tea infusions. Additionally, the antimicrobial activity of the natural and artificial infusions was assessed against three species of bacteria: Gram (+) Staphylococcus epidermidis and Staphylococcus aureus and Gram (−) Escherichia coli. When compared to the natural infusions the artificial beverages did not demonstrate any bacterostatic/cidal activity, suggesting that the antibacterial activity of rooibos is related to compounds other than the glycosylated polyphenols employed in our study.

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Phenolic content and antioxidant activity of rooibos food ingredient extracts

Cited by 49 publications

References 24 publications

Biosorption of Pb(II) from aqueous solution using Rooibos shoot powder (RSP)

Biosorption of Pb(II) from aqueous solution using Rooibos shoot powder (RSP)

Antioxidant activity of flavonoids from leaves of Jatropha curcas

Anti-Peroxyl Radical Quality and Antibacterial Properties of Rooibos Infusions and Their Pure Glycosylated Polyphenolic Constituents

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