Search results for "ANTIOXIDANT ACTIVITY"
showing 10 items of 123 documents
Antioxidant activity and chemical composition of three Tunisian Cistus: Cistus monspeliensis Cistus villosus and Cistus libanotis
2015
The chemical composition of three rockrose Cistus species, Cistus monspeliensis, Cistus libanotis and Cistus villosus, collected in Tunisia, was studied by HPTLC, focusing on the terpenes and phenols constituents. Diterpenes of Cistus are important as the main constituents of the leaf sticky aromatic resin, known as labdanum, which are highly appreciated in perfumery. Polyphenols in the methanolic extracts of each species were identified, quantified as total and as flavonoids and tannins, and tested for antioxidant activity. Diterpenes were evident in C. libanotis and C. monspeliensis, whereas they were practically absent in C. villosus; C. libanotis had higher phenolic amount, whereas anti…
Emulsions based on fatty acid from vegetable oils for cosmetics
2022
Vegetable oils are sources of saturated, monounsaturated and polyunsaturated fatty acids. In this work, we studied the suitability of a mixture of vegetable oils and some fatty acids (similar to the those of the human skin) as a cosmetic emulsion. Hypericum (Hypericum perforatum L.) – 1 %, thistle (Silybum marianum (L.) Gaertn.) – 42 %, linen (Línum usitatíssimum L.) – 1.1 %, wheat germ (Triticum aestivum L.) – 1 %, sesame (Sésamum índicum L.) – 1 %, mustard (Sinápis álba L.) – 2%, pumpkin (Cucúrbita p é po L.) – 5 %, – were selected as vegetable oils. The emulsion based on the proposed mixture of vegetable oils has a higher antioxidant activity (1.623 OD) compared with that based on minera…
The antioxidant capacity of red wine in relationship with its polyphenolic constituents
2008
The aim of this study is evaluate either the antioxidant or pro-oxidant behaviour of some typical polyphenolic compounds of red wine, to investigate the influence of two different pH levels on the antioxidant properties and to clarify their activity–structure relationship. The antioxidant activity of compounds in hydrophilic solutions at pH 3.5 and pH 7.4 were measured by a competition kinetic test, based on the crocin bleaching. The position and the number of substitution groups influence the magnitude of the antioxidant activity of the polyphenolic compounds, but their antioxidant properties are also strongly influenced by the pH conditions. Increasing the pH, a considerable increase in a…
The influence of two different pH levels on the antioxidant properties of flavonols, flavan-3-ols, phenolic acids and aldehyde compounds analysed in …
2011
Abstract The aim of this study is evaluate either the antioxidant or pro-oxidant behaviour of some typical polyphenolic compounds of red wine, to investigate the influence of two different pH levels on the antioxidant properties and to clarify their activity–structure relationship. The antioxidant activity of compounds in hydrophilic solutions at pH 3.5 and pH 7.4 were measured by a competition kinetic test, based on the crocin bleaching. The position and the number of substitution groups influence the magnitude of the antioxidant activity of the polyphenolic compounds, but their antioxidant properties are also strongly influenced by the pH conditions. Increasing the pH, a considerable incr…
Antimicrobial, Antibiofilm, and Antioxidant Properties of Essential Oil of Foeniculum vulgare Mill. Leaves
2022
Foeniculum vulgare (Apiaceae) is an aromatic fennel with important practices in medicinal and traditional fields, used in the treatment of digestive complications, and gastrointestinal and respiratory disorders. Its leaves and stems, tender and fresh, are used in the production of pasta dressing and main courses, while its seeds, with a strong smell of anise, are excellent flavoring for baked goods, meat dishes, fish, and alcoholic beverages. The aim of this work is concerning the extraction of essential oil (EO) from the leaves of F. vulgare subsp. vulgare var. vulgare, investigating antimicrobial, antibiofilm, and antioxidant efficacy. In particular, GC-MS analysis showed how the chemical…
Commercial essential oils: sustainable alternatives in the agri-food industry
2019
Essential oils have enjoyed great popularity from ancient times to today due to agreeable scent and widely known beneficial properties. As a result, nowadays they have become valuable natural ingredients in perfume and cosmetics, food and beverages, agricultural, pharmaceutical and other industries for employment in human health, agriculture and environment, representing potentially safer and more sustainable alternatives to synthetic substances. This Doctoral Thesis has been developed with the aim of corroborating that essential oils are safer and more sustainable alternatives to synthetic products used in the agri-food industry, and consequently promoting their use as “bio” products to ma…
A study of the chemical composition and biological activity of extracts from wild carrot (Daucus carota l.) seeds waste
2015
Waste (wild carrot seeds, Daucus carota L.) formed after the industrial extraction of 96% ethanol were re-extracted with 40% and 70% ethanol in order to recover of valuable substances for potential use as a safe food additives and functional food ingredients or nutraceuticals. In this study we compared chemical composition and activity of two obtained extracts (70% EtOH and 40% EtOH). The results indicated that the 70% EtOH extract has a higher total phenol and flavonoid content than 40% EtOH extract. The antioxidant activity of 70% EtOH extract was 86.88 % ± 3.018, whereas of 40% EtOH extract scavenging activity was 78.72% ± 3.276. The extracts were also active against bacteria with MIC ag…
Antioxidant Activity and Release Kinetics of Caffeic and p-Coumaric Acids from Hydrocolloid-Based Active Films for Healthy Packaged Food
2017
International audience; Sustainable hydrocolloid-based films containing natural antioxidants, caffeic and p-coumaric acids at different concentrations of 0.5%, 1%, 5%, and 10% w/w of polymers, were designed for packing fatty foods. Antioxidant activities and kinetics for all film formulations were assessed using radical scavenging activity (DPPH), reducing power, and iron chelating ability. Release kinetics of the antioxidants from the films into a food simulant (96% ethanol) were analyzed. The intermolecular interactions between antioxidants and polymers chains were assessed by Fourier transform infrared attenuated total reflectance (FTIR-ATR) and related to the film properties. Antioxidan…
Untargeted metabolomics of rind essential oils allowed to differentiate two closely related clementine varieties
2021
[EN] Chemical characterization of clementine varieties (Citrus clementina Hort. ex Tan.) essential oils (EO) can lead to variety identification and valorization of their potential use in food and aroma industries. The goal of this study was the chemometric discrimination between two very closely related and morphologically identical clementine varieties, Clemenules (NL) and Clemenpons (PO), based on their rind EO, to identify the differential volatile organic compounds (VOCs) and to determine their antioxidant capacity. EO rind volatile profile was determined by gas chromatography coupled to mass spectrometry in Citrus fruit at different ripening stages grown two independent years in two di…
Daphne striata Tratt. and D. mezereum L.: a study of anti-proliferative activity towards human cancer cells and antioxidant properties
2018
In this study, we investigated for the first time the anti-proliferative and antioxidant properties of D. mezereum and D. striata. The aerial parts were extracted by maceration with n-hexane, dichloromethane, and methanol. MPLC, GC, and GC-MS were used for the phytochemical study. The anti-proliferative activity was tested against MCF-7, A549, LNCaP, ACHN, and C32 cancer human cells. The antioxidant activity was measured by employing β-carotene bleaching, ABTS, DPPH, and FRAP tests. The Relative Antioxidant Capacity Index (RACI) was applied from the perspective of statistics. D. mezereum dichloromethane extract showed a remarkable anti-proliferative with an IC50 of 6.08 μg/mL against LNCaP …