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Bioactive compounds are widely distributed in plant sources and are the most abundant secondary metabolites of the plants. Based on chemical characterization, they include: glycosides, flavonoids, tannins, terpenoids, lignans, alkaloids, peptides, and others. The extraction of bioactive molecules has drawn increasing attention due to their antioxidant and therapeutic potential through their interactions with vascular endothelial cells to prevent cardiovascular disorders and cancer. Although the development in chromatographic and spectrometric analytical techniques has significant contribution in the detection of bioactive components, the success depends on the method of extraction as two-third part of analytical work is required to get these components. In conventional extraction methods, several combinations of temperature, solvent, agitation speed, and extraction time have been optimized to get maximum yields, but these conventional proposals are creating burden on environment due to high temperatures for a long time and secondly, affect the 4heat-sensitive bioactive components. Alternatively, application of novel techniques like ultrasound, microwave, high pressure, pulsed electric field, supercritical fluid, and others is more welcoming due to less environmental burden in the form of lessened usage of organic solvents, low working temperatures, short duration, and improved quality and yield with high selectivity to compounds of interest. The efficiencies of both either conventional or novel extraction methods are typically based on the input parameters, complexity of plant source, structural conformation of bioactive components, and skill to up-scale them. This chapter aims to discuss basic mechanisms involved in the extraction of bioactive molecules from plant material through conventional as well as novel extraction techniques.

The present study was conducted to evaluate the cytotoxic activity of different extracts of root bark of Capparis decidua (Capparidaceae). The root barks of Capparis decidua were collected from village Kirri khaisore Tehsil Pahar pur, Dera Ismail Khan; shade dried and ground into fine powder. The weighed plant material was then extracted with dichloromethane and methanol in triplicate for 72 hours by the process of successive maceration. The filtrate obtained was concentrated under reduced pressure at 30 °C using rotary evaporator. Brine shrimp lethality bioassays and MTT colorimetric assay were carried out on the extracts to assess the cytotoxic activity. Dichloromethane extract showed moderate brine shrimp lethality activity, while this activity was not shown by methanol extract. Both extract showed no cytotoxic activity. Keywords: Capparis decidua, cytotoxicity, Brine Shrimp

Flavanones are found specifically and abundantly in citrus fruits. Their beneficial effect on vascular function is well documented. However, little is known about their cellular and molecular mechanisms of action in vascular cells. The goal of the present study was to identify the impact of flavanone metabolites on endothelial cells and decipher the underlying molecular mechanisms of action. We investigated the impact of naringenin and hesperetin metabolites at 0.5, 2 and 10 mu M on monocyte adhesion to TNF-alpha-activated human umbilical vein endothelial cells (HUVEC) and on gene expression. Except hesperetin-7-glucuronide and naringenin-7-glucuronide (N7G), when present at 2mM, flavanone metabolites (hesperetin-3'-sulphate, hesperetin-3'-glucuronide and naringenin-4'-glucuronide (N4'G)) significantly attenuated monocyte adhesion to TNF-alpha-activated HUVEC. Exposure of both monocytes and HUVEC to N4'G and N7G at 2 mu M resulted in a higher inhibitory effect on monocyte adhesion. Gene expression analysis, using TaqMan Low-Density Array, revealed that flavanone metabolites modulated the expression of genes involved in atherogenesis, such as those involved in inflammation, cell adhesion and cytoskeletal organisation. In conclusion, physiologically relevant concentrations of flavanone metabolites reduce monocyte adhesion to TNF-alpha-stimulated endothelial cells by affecting the expression of related genes. This provides a potential explanation for the vasculoprotective effects of flavanones

A bunch of epidemiological studies provides good evidence on the inverse relationship associated with the consumption of fruits and vegetables and the chronic diseases importantly cardiovascular diseases and some types of cancers. After the long years of study on phytomacronutrients, the role of phytomicronutrients such as polyphenols is now highly studied and appreciated in the control of such degenerative diseases. The present study combines the extraction, synthetic and analytical studies on the major polyphenols of citrus fruits, FLAVANONES.Awareness of nutritional and health facts has increased the production of citrus fruits from last few decades. These higher productions generate higher by-products. For their alternative utilisation to have antioxidants rich extracts, the ultrasound-assisted extraction (UAE) of polyphenols especially flavanones from orange (Citrus sinensis L.) peel by using ethanol as afood grade solvent has been proved its efficiency when compared with the conventional method. A central composite design (CCD) approach revealed that the optimized conditions for UAE were a temperature of 40°C, a sonication power of 150W and a 4:1 (v/v) ethanol:water ratio. Furthermore, the antioxidant activity determined by the DPPH and ORAC tests confirmed the suitability of UAE for the preparation of antioxidant-rich plant extracts. Flavanone glucuronides are the major phenolic metabolites detected in human plasma after consumption of citrus fruits. Up to now all cell studies related to cancer or cardiovascular diseases were conducted either on the aglycones or on their glycosides. Hence, there is great need of pure flavanone glucuronides to demonstrate the real potential of flavanones in the prevention of these diseases. In this work, glucuronides of naringenin (4′- and 7-O-β-D-glucuronides) and hesperetin (3′- and 7-O-β-D-glucuronides), the major flavanone aglycones in grapefruit and orange respectively, have been chemically synthesized by selective protection and deprotection of flavanone and glucuronic acid moieties. The complete structural characterisation of purified compounds were realised by nuclear magnetic resonance and mass spectrometry.The affinity of the four glucuronides for human serum albumin (HSA) was tested via their ability to quench the intrinsic fluorescence of HSA (single Trp residue in sub-domain IIA). Their binding constants (K) were estimated in the range of 30 – 60 × 103 M-1 and compared with those of the aglycones (70 – 90 × 103 M-1). Investigations of competitive or noncompetitive binding of the glucuronides in the presence of fluorescent probes (dansyl sarcosine) allowed us to get some insight in the binding sites. The study was also extended to the hesperetin and naringenin chalcones (synthesised using optimized alkaline conditions), which are the biosynthetic precursors of flavanones., Un groupe d'études épidémiologiques fournit une bonne preuve de la relation inverse associé à la consommation de fruits et légumes et les maladies chroniques important comme maladies cardiovasculaires et certains types de cancers. Après les longues années d'études sur phytomacronutrients, le rôle de phytomicronutrients tels que les polyphénols est désormais très étudiée et appréciée dans le contrôle de ces maladies dégénératives. La présente étude combine les études d'extraction, de synthèse et d'analyse sur les principaux polyphénols des fruits d'agrumes, FLAVANONES. Connaissance de nutritionnels et de santé a augmenté la production d'agrumes en provenance des dernières décennies. Ces productions plus générer des bye-produits. Pour leur utilisation alternative à des antioxydants extraits riches, l'extraction assistée par ultrasons (UAE) des polyphénols en particulier flavanones de l'orange (Citrus sinensis L.) par son peau en utilisant l'éthanol comme solvant de qualité alimentaire a été prouvé son efficacité en comparaison avec la méthode conventionnelle . Un plan composite central (CCD) a révélé que l'approche des conditions optimisées pour UAE ont une température de 40 ° C, une puissance de 150W sonication et un 4:1 (v / v) d'éthanol: ratio de l'eau. En outre, l'activité antioxydante déterminée par les tests DPPH et ORAC a confirmé la pertinence des UAE pour la préparation d'extraits de plantes riches en antioxydants.Les glucuronides de flavanone sont les principaux métabolites phénoliques détectés dans le plasma humain après la consommation d'agrumes. Jusqu'à maintenant, toutes les études sur les cellules liées au cancer ou les maladies cardiovasculaires ont été réalisées soit sur les aglycones ou sur leurs glycosides. Par conséquent, il ya grand besoin de glucuronides flavanone pure pour démontrer le potentiel réel de flavanones dans la prévention de ces maladies. Dans ce travail, glucuronides de naringénine (4'- et 7-O-β-D-glucuronides) et de hespérétine (3'- et 7-O-β-D-glucuronides), les aglycones flavanone majeur dans le pamplemousse et d'orange, respectivement, ont été synthétisés chimiquement par une protection et la déprotection sélective des groupements d'acide glucuronique et de flavanone. La caractérisation structurale complète de composés purifiés a été réalisée par résonance magnétique nucléaire et spectrométrie de masse.L'affinité des quatre glucuronides pour l'albumine sérum d’humaine (HSA) a été testée par leur capacité à éteindre la fluorescence intrinsèque de HSA (Trp, seul résidu de sous-domaine IIA). Leurs constantes de fixation (K) ont été estimées de l'ordre de 30 à 60 × 103 M-1 et comparées à celles de l'aglycones (70 à 90 × 103 M-1). Les enquêtes de la liaison compétitive ou non compétitive de la glucuronides dans la présence de sondes fluorescentes (sarcosine dansyl) nous a permis d'obtenir un aperçu dans les sites de liaison. L'étude a également été étendue aux chalcones hespérétine et naringénine (synthétisés en utilisant des conditions alcalines optimisée), qui sont les précurseurs de biosynthèse des flavanones.

Diet is a pivotal contributing factor to the onset and progression of some chronic ailments nowadays. The conjugated linoleic acid (CLA), a bioactive component of ruminant fat, introduces more elucidates what we know polyunsaturated fats and diseases. CLA, a mixture of isomers c9, t11 and t10, c12, is the most abundant ranging from 80 to 90% of total CLA isomers and account for most known health benefits. Dairy milk and meat are the major dietary sources of CLA, and its concentration is of great interest to human health. The biofunctionalities of CLA from enriched dairy products are major attributes in the context of a substance present in our everyday diet. Thus, dietary modifications in animal feed, synthetic and microbial production have been made to increase CLA intake to enhance its clinical manifestations. However, the bioavailability and distribution of enriched or supplemented CLA has not been fully elucidated because of its response variation in different animal models. This chapter deals with different dietary sources, availability, enhancement of CLA in dairy products and its positive manifestation against different maladies. In conclusion, it is feasible to produce CLA-enriched dairy products with acceptable storage and sensory characteristics while deriving its nutritional benefits.