The leaves of Mediterranean mandarin could be used as an important source of hesperidin, nobiletin and tangeretin. : S20P04

Citrus are rich in flavonoids such as flavones and flavanones. Recent studies have shown that these phytonutrients play a beneficial role for human health. Citrus plants can contain high levels of hesperidin, a flavanone which is effective in the treatment of chronic venous insufficiency. Nobiletin and tangeretin are two polymethoxylated flavones. Nobiletin has been shown to increase hepatic insulin sensitivity and decrease atherosclerosis. Tangeretin may have antiproliferative and anticarcinogenic effects by blocking MAPKs activation and ROS generation. Studies on flavonoids from citrus are generally focussed on ripe fruits and on one group of metabolites. The aim of this study is to quantify accurately all groups of flavonoid from leaves of mandarin (Citrus deliciosa). Flavones and flavanones analysis was carried out by liquid chromatography and mass spectrometry (LC-MS) using a new generation column. Moreover, a specific gradient was designed to evaluate both flavanones and methoxylated flavones. This method was applied to leaves from mandarin tree. All leaves were fully-expanded, and were about one-year-old from the spring flush of the previous season. They were of similar height above the ground, had the same east orientation and experienced similar exposure to light. Comparison of metabolite levels revealed that mandarin leaves were rich in hesperidin, nobiletin and tangeretin. Interestingly, nobiletin and tangeretin also accumulated in high level. (Texte integral

chemotaxis of rhizobium phaseoli towards flavones and other related compounds

The formation of nitrogen-fixing nodules on leguminous plants is the result of a highly specific interaction between the host plant and the soil bacterium Rhizobium. Two observations suggest that chemotaxis may play a role in the establishment of the legume-Rhizobium symbiosis: 1) The widespread occurence of Rhizobium species with flagella (Gotz, 1982; Carlile. 1980)2) The copious exudation into the soil surrounding legume roots of a wide variety of potentially chemotactic compounds which include amino acids, sugars and sugar-acids. (Beringer et.al.,1979). Recently the plant flavones luteolin (3,44,7 - Tetra - hydroxyflavone) and apigenin (4,5,7 - Trihydroxy-flavone) have been reported as inducers of Rhizobium nodulation genes (Peters, 1986, Rolfe 1986). We report here that R. phaseoli (RP8002) exhibits positive chemotaxis toward both flavones. Other diverse compounds tested elicited different responses. An understanding of the influence of flavones in two events such as chemotaxis and nodulation efficiency can be valuable to clarify their action in the intricate legume-rhizobia interaction

Influence of Processing on Bioactive Substances Content and Antioxidant Properties of Apple Purée from Organic and Conventional Production in Poland

The organic food market is developing dynamically in many European countries and therefore studies concerning the nutritive value of organically produced foods are becoming increasingly important. It was found appropriate to conduct studies on selected bioactive substances and antioxidant properties of apple preserves prepared from organic vs. conventional apples. Three apple cultivars, Lobo, Boskoop and Cortland, were grown in organic and conventional orchards in the Mazovia region in Poland. Dry matter, total phenols, vitamin C, total flavones and antioxidant activity were determined in fresh and pasteurized apple purée. The apple purée prepared from the organic apples contained significantly more total phenols, vitamin C, total flavones and showed a higher antioxidant capacity than the preserves prepared from conventional apples. Processing had a negative effect on both antioxidant capacity and bioactive substances. After pasteurization, the content of vitamin C, total phenols and flavones and antioxidant properties have decreased in the apple purée from both agricultural systems (organic and conventional)

Comparison of the Nutritive Quality of Tomato Fruits from Organic and Conventional Production in Poland

Organic horticulture is generally accepted as friendly to the environment, good for crop quality and also for the consumer’s health. Recent research data has shown that organic crops under organic farming practices contained more bioactive substances such as flavones, vitamin C, carotenoids; they also contain less pesticides residues, nitrates and nitrites. Five tomato cultivars: four large – fruit (Rumba, Juhas, Kmicic, Gigant) and one cherry cultivar (Koralik) were selected for study. The organic tomato fruits contained more dry matter, total and reducing sugars, vitamin C, total flavones and beta-carotene, but less lycopene in comparison to conventionally grown tomatoes

Flavonoid intake and the risk of age-related cataract in China’s Heilongjiang Province

Background/Objectives: Epidemiological evidence suggests that diets rich in flavonoids may reduce the risk of developing age-related cataract (ARC). Flavonoids are widely distributed in foods of plant origin and the objective of this study was to evaluate retrospectively the association between the intakes of the five flavonoid subclasses and the risk of ARC.  Subjects/Methods: A population-based case-control study (249 cases and 66 controls) was carried out in Heilongjiang province, which is located in the Northeast of China, and where intakes and availability of fresh vegetables and fruits can be limited. Dietary data gathered by food-frequency questionnaire (FFQ) were used to calculate flavonoid intake. Adjusted odds ratio (OR) and 95% confidence interval (CI) were estimated by logistic regression.  Results: No linear associations between risk of developing ARC and intakes of total dietary flavonoids, anthocyanidins, flavon-3-ol, flavanone, total flavones or total flavonols were found, but quercetin and isorhamnetin intake was inversely associated with ARC risk (OR 11.78, 95% CI: 1.62-85.84, P<0.05, and OR 6.99, 95% CI:1.12-43.44, P<0.05, quartile 4 vs quartile 1, respectively).  Conclusion: As quercetin is contained in many plant foods and isorhamnetin is only contained in very few foods, we concluded that higher quercetin intake may be an important dietary factor in the reduction of risk of age-related cataract

Mechanism and Application of Baker–Venkataraman O→C Acyl Migration Reactions

This literature review focuses on the O→C acyl migration of aryl esters to yield the corresponding 1,3-dicarbonyl products—a reaction known as the Baker–Venkataraman rearrangement—and outlines their subsequent transformations. The purpose of the review is to highlight the utility of the rearrangement which provides a key step in the synthesis of various heterocyclic motifs. The scope of the Baker–Venkataraman rearrangement is illustrated by way of numerous examples of its application, and in doing so, the review contains over 100 references and covers just over 100 years of the literature, from the first report of the rearrangement by Auwers in 1910 up to more recent examples in the past few years. 1 Introduction 2 Historical Perspective 3 Mechanism 4 Applications: General Routes to Heterocycles 4.1 Flavones and Flavanones 4.2 Xanthones 4.3 Chromones 4.4 Coumarins 4.5 Anthrapyran and Anthracyclin Antibiotics 4.6 Benzopyrans 5 The Retro-Baker–Venkataraman Rearrangement 6 Summary and Outloo

Habitual intake of flavonoid subclasses and risk of colorectal cancer in two large prospective cohorts

Background: Flavonoids inhibit the growth of colon cancer cells in vitro. In a secondary analysis of a randomized controlled trial, the Polyp Prevention Trial, a higher intake of one sub-class, flavonols, was significantly associated with reduced risk of recurrent advanced adenoma. Most previous prospective studies on colorectal cancer evaluated only a limited number of flavonoid sub-classes and intake ranges, yielding inconsistent results.  Objective: To examine whether higher habitual dietary intakes of flavonoid subclasses (flavonols, flavones, flavanones, flavan-3-ols and anthocyanins) are associated with lower risk of colorectal cancer.  Design: Using data from validated food frequency questionnaires administered every four years and an updated flavonoid food composition database flavonoid intakes were calculated for 42,478 male participants from the Health Professionals Follow-up Study and for 76,364 female participants from the Nurses’ Health Study.  Results: During up to 26 years of follow-up, 2,519 colorectal cancer cases (1,061 in men, 1,458 in women) were documented. Intakes of flavonoid subclasses were not associated with risk of colorectal cancer in either cohort. Pooled multivariable adjusted relative risks (95% confidence interval) comparing the highest with the lowest quintile were 1.04 (0.91, 1.18) for flavonols; 1.01 (0.89, 1.15) for flavones; 0.96 (0.84, 1.10) for flavanones; 1.07 (0.95, 1.21) for flavan-3-ols; and 0.98 (0.81, 1.19) for anthocyanins (all p-values for heterogeneity by sex >0.19). In subsite analyses, flavonoid intake was also not associated with colon or rectal cancer risk.  Conclusion: Our findings do not support the hypothesis that a higher habitual intake of any flavonoid sub-class decreases the risk of colorectal cancer

Betalains and phenolic compounds of leaves and stems of Alternanthera brasiliana and Alternanthera tenella

Betacyanins and phenolic compounds from acetonitrile:acidified water extracts of Alternanthera brasiliana and Alternanthera tenella were characterized and quantified using a high-performance liquid chromatography system coupled with diode array and electrospray mass spectrometry detection. Four betacyanins (amaranthine, isoamaranthine, betanin and isobetanin) were tentatively identified and quantified. Twenty eight phenolic compounds of four different families (hydroxybenzoic and hydroxycinnamic acids, flavones and flavonols) were separated and characterized on the basis of their accurate MS and MS/MS information out of which ten compounds were confirmed by authentic standards. These plant species could be considered as an especially rich source of natural bioactive compounds and potential food colorants. A. brasiliana showed the highest betacyanin and polyphenols content (89 μg/g and 35,243 μg/g, respectively). Among polyphenols, flavonols were the more abundant (kaempferol-glucoside, kaempferol-rutinoside and kaempferol-rhamnosyl-rhamnosyl-glycoside). Meanwhile, A. tenella showed a different polyphenols profile with flavones as major compounds (glucopyranosil-vitexin and vitexin). As a novelty, pentosyl-vitexin and pentosyl-isovitexin were detected for the first time in Alternanthera plants. Both A. brasiliana and A. tenella leaves showed high total polyphenol content and in vitro antioxidant activity (FRAP). These results provide an analytical base concerning the phenolic and betalains composition and the antioxidant properties of two members of the promising Alternanthera gender, for subsequent applications, such as functional food ingredients.Fil: Deladino, Lorena. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Alvarez, I.. Consejo Superior de Investigaciones Científicas. Instituto de Ciencia y Tecnologia de Alimentos y Nutrición; EspañaFil: De Ancos, B.. Consejo Superior de Investigaciones Científicas. Instituto de Ciencia y Tecnologia de Alimentos y Nutrición; EspañaFil: Sánchez Moreno, C.. Consejo Superior de Investigaciones Científicas. Instituto de Ciencia y Tecnologia de Alimentos y Nutrición; EspañaFil: Molina García, A. D.. Consejo Superior de Investigaciones Científicas. Instituto de Ciencia y Tecnologia de Alimentos y Nutrición; EspañaFil: Schneider Teixeira, Aline. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina. Consejo Superior de Investigaciones Científicas. Instituto de Ciencia y Tecnologia de Alimentos y Nutrición; Españ

Diversity of secondary metabolites from Genus Artocarpus (Moraceae)

Abstrak. Hakim A. 2010. Keanekaragaman metabolit sekunder Genus Artocarpus (Moraceae). Nusantara Bioscience 2:146-156. Beberapa spesies dari genus Artocarpus (Moraceae) telah diteliti kandungan bahan alamnya. Metabolit sekunder yang berhasil diisolasi dari genus Artocarpus terdiri dari terpenoid, flavonoid, stilbenoid, arilbenzofuran, neolignan, dan adduct Diels-Alder. Kelompok flavonoid merupakan senyawa yang paling banyak ditemukan dari tumbuhan Artocarpus. Senyawa flavonoid yang telah berhasil diisolasi dari tumbuhan Artocarpus memiliki kerangka yang beragam seperti calkon, flavanon, flavan-3-ol, flavon sederhana, prenilflavon, oksepinoflavon, piranoflavon, dihidrobenzosanton, furanodihidrobenzosanton, piranodihidrobenzosanton, kuinonosanton, siklolopentenosanton, santonolid, dihidrosanton. Kata kunci: Artocarpus, Moraceae, flavonoid, Diels-Alder, metabolit sekunder

Antioxidant activity of thyme waste extract in O/W emulsions

Thymus vulgaris (thyme) is an aromatic plant and its essential oil has been applied as antimicrobial and antioxidant due to the presence of phenolic compounds. However, after steam distillation, the deodorized plant material is rejected, despite the possible presence of bioactive compounds. Ethanolic thyme waste extract revealed the presence of benzoic acid, 4-hydroxybenzoic acid, ferulic acid, caffeic acid, and sinapic acid. This waste thyme extract had the capacity for preventing the formation of primary and secondary lipid oxidation products in emulsions O/W (oil in water), constituted by diverse proportions of wheat and almond oils, without interfering with the viscosity parameters, for 10 weeks, at 37 °C. The increasing proportion of almond oil (≥50%) in the emulsion increases its resistance to oxidation, which is improved with the presence of an optimal concentration of tested thyme waste extract (0.02% and 0.04%). The waste thyme extract can, therefore, be used as an antioxidant either in food or pharmaceutical emulsions O/W, replacing the synthetic antioxidants.Agência financiadora Fundacao para a Ciencia e Tecnologia-FCT; Portugal UID/BIA/04325/2013-MEDTBIO UID/MAR/00350/2013info:eu-repo/semantics/publishedVersio