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Investigation of the antioxidant activity of Illicium verum extracts

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Illicium verum has been widely used in many Asian countries as a spice and pharmaceutical treatment for many diseases. In this study, the antioxidant properties of the ethanol extracts fractionated by hexane, ethyl ether, chloroform and ethyl acetate, and supercritical CO 2 extracts of the plant were evaluated using 1,1-diphenyl-2-picryhydrazyl (DPPH) radical scavenging effect, the total equivalent antioxidant capacity and a reducing power assay. In addition, the amount of total phenolic content and the flavonoid content were also determined. The ethyl acetate fractions contained substantially higher levels of total phenolics (4.5 g gallic acid / 100 g dry weight) and total flavonoids (6.9 g quercetin/100 g dry weight) than the other extracts, and possessed significant antioxidant activities. The chemical components of the various extracts were analyzed by gas chromatography-mass spectrometry (GC-MS); anisyl acetone and anisyl aldehyde were evidenced to provide the slight antioxidant activities. Based on the results, it can be concluded that the ethyl acetate extracts of I. verum show a marked antioxidant potential and that they could be developed as a natural source of antioxidants.
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Illicium verum Hook f. (star anise) is considered an important species in Traditional Chinese Medicine and is also used in contemporary medicine in East Asian countries. It occurs in natural habitats in southeastern parts of China and Vietnam, and is cultivated in various regions in China. The raw materials - Anisi stellati fructus and Anisi stellati aetheroleum obtained from this species exhibit expectorant and spasmolytic activities. The European Pharmacopoeia (4th edition) indicates that these raw materials have been used in allopathy since 2002. The biological activities of the above-mentioned raw materials are determined by the presence of valuable secondary metabolites such as monoterpenoids, sesquiterpenoids, phenylpropanoids, and flavonoids. Recent pharmacological studies on fruit extracts and the essential oil of this species have confirmed their antibacterial, antifungal, anti-inflammatory, and antioxidant activities and thus their medicinal and cosmetic value. The aim of this review was to examine the progress of phytochemical and pharmacological studies that focused on possible cosmetic applications. In addition to fruit extracts and essential oil, the current consensus on the safety of trans-anethole, which is the main compound of essential oil used in cosmetology, is underlined here.
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... This classification of I. verum ensures low toxicity to humans 14 . Padmashree et al. 15 and Cheng Hong et al. 16 reported that star anise -both plant and its extract -is an effective source of natural antioxidants. It contains high amounts of polyphenols such as anethole 17 . ...
... It was concluded in this study that I. verum possesses effective prevention ability against H 2 O 2 induced cell death and DNA protection. Cheng et al [29] conducted a study in which results showed that the ethyl acetate fractions of I. verum have free radical scavenging effects and reducing power effect. The strong correlation between its DPPH and TEAC values with those obtained from the reducing power assay implied that the antioxidants in the extracts were capable of scavenging free radicals and reducing oxidants. ...
... It was concluded in this study that I. verum possesses effective prevention ability against H 2 O 2 induced cell death and DNA protection. Cheng et al [29] conducted a study in which results showed that the ethyl acetate fractions of I. verum have free radical scavenging effects and reducing power effect. The strong correlation between its DPPH and TEAC values with those obtained from the reducing power assay implied that the antioxidants in the extracts were capable of scavenging free radicals and reducing oxidants. ...
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