Search results for "Active components"
showing 10 items of 13 documents
ChemInform Abstract: 1H-Naphtho(2,1-b)thiete and 2H-Naphtho(2,3-b)thiete - Synthesis and Reactivity.
2010
Abstract The title compounds 4 and 8 are obtained by flash vacuum pyrolysis of the corresponding hydroxymethylthionaphthols 3 and 7. Whereas 4 shows a smooth ring opening on heating, 8 is thermally stable but reacts photochemically. The different behavior is explained on the basis of an MNDO calculation. The valence isomers 4′ and 8′ represent thioquinonemethides, which are highly reactive components in [12π + 2π]cycloaddition processes (4 → 9, 10, 11; 8 → 12).
Prophylaxis of Non-communicable Diseases: Why fruits and vegetables may be better chemopreventive agents than dietary supplements based on isolated p…
2019
The World Health Organization (WHO) report from 2014 documented that non-communicable socalled civilization diseases such as cardiovascular disease, chronic respiratory diseases, cancer or type 2 diabetes are responsible for over 50% of all premature deaths in the world. Research carried out over the past 20 years has provided data suggesting that diet is an essential factor influencing the risk of development of these diseases. The increasing knowledge on chemopreventive properties of certain food ingredients, in particular, those of plant origin, opened the discussion on the possibility to use edible plants or their active components in the prevention of these chronic diseases. Health-pro…
Variation in contents of main active components and antioxidant activity in leaves of different pigeon pea cultivars during growth.
2013
Pigeon pea is an important and multiuse grain legume crop, and its leaves are a very valuable natural resource. To obtain a high-quality biological resource, it is necessary to choose the excellent cultivar and determine the appropriate harvest time. In this study, the variation in contents of main active components and antioxidant activity in leaves of six pigeon pea cultivars during growth were investigated. The level of each individual active component significantly varied during growth, but with a different pattern, and this variation was different among cultivars. Flavonoid glycosides orientin, vitexin, and apigenin-6,8-di-C-α-L-arabinopyranoside showed two peak values at mid-late and …
Screening and authentication of herbal formulations based on microextraction-assisted voltammetry of microparticles
2015
A simple solid state electrochemical methodology for screening and authentication of herbal formulations is described. The proposed method is based on the recording of the voltammetric response, in contact with aqueous buffers, of microparticulate films of antioxidant compounds resulting from micro-extraction of dried herbal samples with ethanol or acetone. The obtained voltammetric responses led us to differentiate between diverse active components upon application of bivariate and multivariate chemometric techniques. Resolution of herbal preparations containing two or more components is possible when well-separated voltammetric signals are recorded. In favorable cases, such characteristic…
Evaluation of antioxidant properties and assessment of genetic diversity of Capparis spinosa cultivated in Pantelleria Island.
2017
Capparis spinosa is a wild and cultivated bush, which grows mainly in the Mediterranean Basin. Unopened flower buds, called capers are used in the Mediterranean cuisine as flavoring for meat, vegetable and other foods. Several studies evaluated bioactive component and antioxidant activity of Capparis spinosa, increasing the market demand and the economic importance of capers.The aim of this work was to evaluate the contents of bioactive compounds in floral buds fermented in salt of C. spinosa collected from different areas of Pantelleria Island (Italy), testing the effect on healthy function as total antioxidant compounds. Hydrophilic extracts of C. spinosa from Pantelleria Island were char…
Comparative Antiproliferative and Antiangiogenic Activity of Cacao Preparations (P06-048-19)
2019
OBJECTIVES: Multiple lines of evidence show the benefits of cacao on inflammation and cardiovascular disease. The relationship between cacao and cancer is less well defined. Cacao contains bioactive compounds with antiangiogenic properties, such as procyanidins and catechins. Angiogenesis, blood vessel formation, is critical for tumor growth and validated target in cancer therapy. We studied the antiangiogenic and anti-tumorigenic potential of two commercially available 100% cacaos (Valrhona and De Zaan). METHODS: L5178y mouse lymphoma cells were incubated with different concentrations of cacao (0, 0.1, 0.3, 1, 3, and 10 µl/ml). The calorimetric methylthiazolyldiphenyl-tetrazolium bromide (…
UV-Induced Changes of Active Components and Antioxidant Activity in Postharvest Pigeon Pea [Cajanus cajan (L.) Millsp.] Leaves
2013
In this study, the effect of UV irradiation (UV-A, UV-B, and UV-C) on phytochemicals, total phenolics, and antioxidant activity of postharvest pigeon pea leaves was evaluated. The response of pigeon pea leaves to UV irradiation was phytochemical specific. UV-B and UV-C induced higher levels of phytochemicals, total phenolics, and antioxidant activity in pigeon pea leaves compared with UV-A. Furthermore, UV-B irradiation proved to possess a long-lasting effect on the levels of phenolics and antioxidant activity. After adapting for 48 h at 4 °C following 4 h UV-B irradiation, total phenolics and antioxidant activity were approximately 1.5-fold and 2.2-fold increased from 39.4 mg GAE/g DM and …
1H-naphtho[2,1-b]thiete and 2H-naphtho[2,3-b]thiete- synthesis and reactivity
1994
Abstract The title compounds 4 and 8 are obtained by flash vacuum pyrolysis of the corresponding hydroxymethylthionaphthols 3 and 7. Whereas 4 shows a smooth ring opening on heating, 8 is thermally stable but reacts photochemically. The different behavior is explained on the basis of an MNDO calculation. The valence isomers 4′ and 8′ represent thioquinonemethides, which are highly reactive components in [12π + 2π]cycloaddition processes (4 → 9, 10, 11; 8 → 12).
Spectrophotometry: Pharmaceutical Applications
2013
Pharmaceutical analysis is mainly focussed in drug analyses, in raw materials and pharmaceutical formulations, involving the determination of active components, impurities, excipients, content uniformity, solubility, dissolution rate and stability.
Selected plant essential oils and their main active components, a promising approach to inhibit aflatoxigenic fungi and aflatoxin production in food.
2018
Recent research has showed that Aspergillus flavus and Aspergillus parasiticus are aflatoxigenic species that can become very competitive in the framework of climate change. Aflatoxins show carcinogenic, mutagenic, immunotoxic and teratogenic effects on human and animals. Effective and sustainable measures to inhibit these species and aflatoxins in food are required. Origanum vulgare and Cinnamomum zeylanicum essential oils (EOs) and their major active constituents, carvacrol and cinnamaldehyde, respectively, were assayed for inhibiting these species and aflatoxin production in maize extract medium under different environmental conditions. Doses of 10-1000 mg l