Francisco Delgado-Vargas

Natural Pigments: Carotenoids, Anthocyanins, and Betalains — Characteristics, Biosynthesis, Processing, and Stability

Pigments are present in all living matter and provide attractive colors and play basic roles in the development of organisms. Human beings, like most animals, come in contact with their surroundings through color, and things can or cannot be acceptable based on their color characteristics. This review presents the basic information about pigments focusing attention on the natural ones; it emphasizes the principal plant pigments: carotenoids, anthocyanins, and betalains. Special considerations are given to their salient characteristics; to their biosynthesis, taking into account the biochemical and molecular biology information generated in their elucidation; and to the processing and stability properties of these compounds as food colorants.

Natural Colorants for Food and Nutraceutical Uses

Colorants: From the Physical Phenomenon to their Nutraceutical Properties: An Overview The Color Phenomenon Definition Human Perception Measurement Pigments Definition A World of Colorless Compounds Pigments in Biology Molecular Affinities of Pigments Natural Distribution of Pigments Classification of Food Colors Choice and Application of Colors Pigments as Food Colorants Colorants as Food Additives Safety of Food Colorants Inorganic and Synthetic Pigments: History, Sources and Uses Inorganic Synthetic Analytical Techniques and the Evaluation of Color Purity Natural Pigments: A Global Perspective Distribution Functions Carotenoids Definition Classification and Nomenclature Distribution Biosynthesis: Biochemistry and Molecular Biology Functions Methodological Aspects Carotenoids as Food Colors Processing and Stability Production of Carotenoids in Bioreactors Anthocyanins and Betalains Anthocyanins Betalains Other Natural Pigments Chlorophylls Caramel Turmeric Cochineal, Carmine and other Natural Pigments from Insects Monascus Iridoids Chemicals and Colorants as Nutraceuticals Fundamentals Nutraceuticals and Related Terms: Definitions Food Items as Nutraceuticals Natural Colorants as Nutraceuticals Nutraceuticals: The Perspective Appendix: List of Abbreviations

Effects of enzymatic treatments on carotenoid extraction from marigold flowers (Tagetes erecta)

Three techniques were used to quantitate total carotenoids extracted from fresh marigold flowers previously treated with a commercial enzyme; the shortest technique, based on carotenoid extraction with hexane, was selected to evaluate the efficiency of five commercial enzymes in the carotenoid extraction process. Fresh marigold treated with enzymes showed a higher susceptibility to pigment extraction than untreated samples, and the highest carotenoid yields were obtained using the enzyme ECONASE-CEP. This enzyme at 0.1% w/w increased extraction from 1.7 to 7.4 g/kg of marigold flower in dry weight; such treatments may enhance carotenoid extraction at the industrial level as well.

Correlation of HPLC and AOAC Methods to Assess the All-trans-Lutein Content in Marigold Flowers

A reversed-phase C 30 high-performance liquid chromatography (HPLC) method was used to separate the lutein isomers of marigold flowers. The pigments were extracted from marigold meal by an Association of Official Analytical Chemists (AOAC) modified method. The unsaponified extract showed the presence of several lutein ester isomers and after saponification four major lutein isomers were detected. The relationship between all-trans-lutein, assessed by HPLC, and total xanthophylls, assessed by AOAC, was determined. A regression equation, with a high correlation coefficient (r 2 = 0.972), which allows for the calculation of all-trans-lutein from total xanthophylls content is proposed.

Solution-phase parallel synthesis of substituted chalcones and their antiparasitary activity against Giardia lamblia

A library of 25-membered chalcones was prepared by parallel synthesis. Substituted acetophenones and benzaldehydes were condensed using the Claisen-Schmidt base-catalyzed aldol condensation. Several chalcones showed in vitro antiparasitic activity against Giardia lamblia. The highest activity observed for the IC(50) values were 12.72, 15.05 and 15.31 microg/mL, respectively; these are potential leads for the development of antigiardial compounds.

Enzymatic treatment to enhance carotenoid content in dehydrated marigold flower meal

The effect of enzymatic treatments using a commercial enzyme (Econase-cep at pH 5.0 and 0.1% w/w concentration) at different levels of dehydrated marigold meal (5, 10, 15 and 20% dry weight), to enhance carotenoid extraction, was evaluated. The AOAC method consisting of a simultaneous extraction and saponification by using hexane-ethanol-acetonetoluene (10:6:7:7 v/v) and metanolic KOH (40% w/v) was used to evaluate the carotenoid content. The measurement of carotenoids was also carried out in samples in which the water soluble compounds were previously eliminated (AOAC-H2O). Total carotenoids ranged from 11.4 to 17. 4 g/kg and 18 to 24.7 g/kg of control and treated marigold meal, respectively. Highest amount of carotenoids were noted when 5% level of treated meal was used.

Phenolic Content and Antioxidant and Antimutagenic Activities in Tomato Peel, Seeds, and Byproducts

The phenolic content and antioxidant and antimutagenic activities from the peel and seeds of different tomato types (grape, cherry, bola and saladette type), and simulated tomato industrial byproducts, were studied. Methanolic extracts were used to quantify total phenolic content, groups of phenolic compounds, antioxidant activities, and the profile of phenolic compounds (by HPLC-DAD). Antimutagenic activity was determined by Salmonella typhimurium assay. The total phenolic content and antioxidant activity of tomato and tomato byproducts were comparable or superior to those previously reported for whole fruit and tomato pomace. Phenolic compounds with important biological activities, such as caffeic acid, ferulic acid, chlorogenic acids, quercetin-3-β-O-glycoside, and quercetin, were quantified. Differences in all phenolic determinations due to tomato type and part of the fruit analyzed were observed, peel from grape type showing the best results. Positive antimutagenic results were observed in all samples. All evaluated materials could be used as a source of potential nutraceutical compounds.

Microwave-assisted synthesis of hydropyridines and study of the DPPH-scavenging activity

A series of hydropyridines (HPs) were synthesized using dimedones, ethyl acetoacetate, ammonium acetate and appropriate aldehydes under solvent-free conditions and microwave-irradiation through Hantzsch reaction. All the synthesized HPs were tested in vitro for the 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity and structure–activity relationship was discussed; only 12 out of the 36 HPs showed antioxidant activity. Polyhydroquinolines (PHQs) were the most active compounds among the studied HPs, they were characterized by the lack of an ester-like structure substituent at carbon 5.

Antifungal activity of fruit pulp extract from Bromelia pinguin

The methanol extract of the fruit pulp of Bromelia pinguin was evaluated for its antifungal activity. The extract showed a significant activity against some Trichophyton strains, although Candida strains were generally insensitive.

Potential of vegetated ditches to manage organic pollutants derived from agricultural runoff and domestic sewage: A case study in Sinaloa (Mexico)

This case study presents the fate of selected organic, priority and emerging pollutants along a 3.6km sector of a vegetated, agricultural ditch situated in Sinaloa (Mexico). The ditch receives runoff of agriculture and domestic wastewater from an adjacent community. During 2013, the occurrence of 38 organic pollutants (pesticides, polycyclic aromatic hydrocarbons (PAHs), artificial sweeteners and pharmaceutical residues) was monitored monthly at five selected points in the ditch water. Additionally, sediment and Typha domingensis (cattail) plants were collected in March, June, and September 2013 and investigated concerning their ability to absorb and accumulate pollutants. The concentrations of the selected pollutants in the ditch water ranged from sub ngL-1 (metolachlor, atrazine) to μgL-1 (metalaxyl, acesulfame). The metabolites endosulfan sulfate and endosulfan lactone exceeded mostly the concentration of the precursor insecticide endosulfan. Sorption on sediments was of minor relevance for accumulation of pollutants in the ditch system. Concentrations in the sediments varied seasonally and ranged from 0.2 to 12,432μgkg-1 dry weight (d.w.). T. domingensis accumulated ten of the studied pollutants mainly in roots (5-1065μgkg-1 d.w.). Overall, the monitoring results of the ditch compartments indicated that downstream the concentrations of the target pollutants decreased. Under no-flow conditions in the hot season, the ditch revealed a noticeable potential to mitigate pollutants. Among the high microbial activity in the water and the subtropical climate conditions, the ditch vegetation contributed to natural attenuation of the selected pollutants.