betalains and betalamic-acid

Currently, the demand for natural colorants is increasing instead of synthetic colorants for foodstuff, because they are harmless to human health. Betalain is group of compounds containing nitrogen and water soluble pigment. Betalain is classified into two main classes, betacyanin which is the condensation of betalamic acid with cyclo-DOPA and betaxanthin which is the conjugation of amino acid or amines with betalamic acid. They are used to color various foods and medicines. Betalain is different from anthocyanin because betalains contain nitrogen in their structures. It is interesting to hear that betalains and anthocyanins are individually significant but they have not seen together in the same plant. Their stability influenced by various factors such as, temperature, pH, water activity and light. In this review basic chemistry of betalains, classes, subclasses, their sources and biosynthesis, factors affecting their stability, health and food industry applications are discussed. Moreover, mentioned work signifies the potent anticancer, antioxidant and antimalarial activities of betalains, furthermore provides a help to do more scientific work on it.

Topics: Antimalarials; Antioxidants; Betacyanins; Betalains; Dihydroxyphenylalanine; Food Coloring Agents; Humans; Picolinic Acids; Pyridines

Betalains are vacuolar pigments composed of a nitrogenous core structure, betalamic acid [4-(2-oxoethylidene)-1,2,3,4-tetrahydropyridine-2,6-dicarboxylic acid]. This compound consists of a chromophore substructure 1,7-diazaheptamethin. Betalamic acid condenses with imino compounds (cyclo-DOPA or its glucosyl derivatives), or amines and/or their derivatives to form a variety of betacyanins (violet) and betaxanthins (yellow), respectively. These pigments exhibit absorption maxima in between 532-550 nm and 457-485 nm, respectively. These colors are currently in use as food additives as they are bioactive and completely safe to consume. However, owing to poor stability, their potential application in pharmaceuticals and cosmetics is severely compromised. There is a lack of scientific reports highlighting their superior tinctorial strength including fluorescence, and their excellent water solubility. For widening the color spectrum and their usage, various betalain-rich extracts have been reviewed here, focusing on their matrix effects on stability vis-a-vis purified pigments of different structural make-up. This review also encompasses work carried out in the past related to stability/stabilization of betalains and future research direction for the same.

Topics: Betacyanins; Betalains; Fluorescence; Protein Stability; Pyridines

Natural products are an excellent source of inspiration for the development of new drugs. Among them, betalains have been extensively studied for their antioxidant properties and potential application as natural food dyes. Herein, we describe the seven-step synthesis of new betalamic acid analogs without carboxy groups in the 2- and 6-position with an overall yield of ~70%. The Folin-Ciocalteu assay was used to determine the antioxidant properties of protected intermediate

Topics: Antioxidants; Betalains; Pyridines; Pyrrolidines

With two compounds first discovered in quinoa, an entire novel family of betalain pigments derived from dopamine is obtained and characterized. Betalains are nitrogenous water-soluble pigments and bioactive molecules with health-promoting effects and nutraceutical potential. It was assumed that all betalains contained betalamic acid as a structural unit derived from l-dihydroxyphenylalanine (l-DOPA). However, hitherto ignored compounds derived from dopamine have recently been discovered in nature. Here an entire family of betalains is described as decarboxylated pigments where 6-decarboxy-betalamic acid is the chromophoric and structural unit. This paper shows for the first time the production, purification and characterization of color and fluorescent properties of this novel family of pigments. Antioxidant and anti-aging effects of the just discovered betalains were tested in vivo using the animal model Caenorhabditis elegans. Some of them presented extraordinary properties, being glutamic acid-6-decarboxy-betaxanthin the most fluorescent molecule among both families of betalains. Methionine sulfoxide-6-decarboxy-betaxanthin is described as the most potent betalain in the reduction of oxidative stress in vivo in C. elegans (99.5 % at 25 µM) and dopa-6-decarboxy-betaxanthin increased the lifespan of the animal model up to 7.0 % at 25 µM. These results open new research lines in the search for molecules from plants with health-promoting properties and bioactivities.

Topics: Animals; Betalains; Betaxanthins; Caenorhabditis elegans; Coloring Agents; Disease Models, Animal; Dopamine

Betalains are water-soluble nitrogen-containing pigments with multiple bioactivities. Pitayas are the only at large-scale commercially grown fruit containing abundant betalains for consumers. Currently, the key genes involved in betalain biosynthesis remain to be fully elucidated. Moreover, genome-wide analyses of these genes in betalain biosynthesis are not available in betalain-producing plant species. In this study, totally 53 genes related to betalain biosynthesis were identified from the genome data of

Topics: Betalains; Cactaceae; Fruit; Gene Expression Regulation, Plant; Genes, Plant; Genome-Wide Association Study; Pigmentation; Pyridines

Diverse arrays of naturally occurring compounds in plants are synthesized by specialized metabolic enzymes, many of which are distributed taxonomically. Although anthocyanin pigments are widely distributed and ubiquitous, betalains have replaced anthocyanins in most families in Caryophyllales. Anthocyanins and betalains never occur together in the same plant. The formation of betalamic acid, catalyzed by 3,4-dihydroxyphenylalanine (DOPA) 4,5-extradiol dioxygenase (DOD), is a key step in betalain biosynthesis. DODs in betalain-producing plants are coded by LigB genes, homologs of which have been identified in a wide range of higher plant orders, as well as in certain fungi and bacteria. Two classes of LigB homologs have been reported: those found in anthocyanin-producing species and those found in betalain-producing species, which contain DOD. To gain insight into the evolution of specialized metabolic enzymes involved in betalain biosynthesis, we performed a comparative biochemical analysis of Arabidopsis LigB, an extradiol ring-cleavage dioxygenase in anthocyanin-producing Arabidopsis and Phytolacca DOD1 of betalain-producing Phytolacca americana. We show that Arabidopsis LigB catalyzes 2,3-extradiol cleavage of DOPA to synthesize muscaflavin, whereas Phytolacca DOD1 converts DOPA to betalamic acid via 4,5-extradiol cleavage. Arabidopsis LigB also converts caffeic acid, a ubiquitous phenolic compound in higher plants, to iso-arabidopic acid in vitro via 2,3-extradiol cleavage of the aromatic ring. Amino-acid substitution in Arabidopsis LigB and Phytolacca DOD1 led to variable extradiol ring-cleavage function, supporting the suggestion that catalytic promiscuity serves as a starting point for the divergence of new enzymatic activities.

Topics: Amino Acid Substitution; Arabidopsis Proteins; Betalains; Dihydroxyphenylalanine; Dioxygenases; Phytolacca americana; Plant Proteins; Pyridines

Although betanin is commonly used as a water-soluble red colorant in foods, it is unstable when heated. In this study, the discoloration of betanin in a buffer solution was kinetically studied in the pH range of 2.6 to 7.6 at 40 °C to 80 °C. The absorption spectrum of betanin was deconvoluted into the spectra of betanin and its degradation product, betalamic acid. Subsequently, a reversible consecutive reaction, in which betanin was reversibly degraded to betalamic acid, and betalamic acid was further degraded, was assumed to calculate the first-order rate constant of each step. The apparent reaction mechanism varied depending on the pH values. Based on these rate constants, the activation energy of each process, as well as the equilibrium constant and enthalpy change for the reversible reaction between betanin and betalamic acid were evaluated.

Topics: Betacyanins; Betalains; Food Coloring Agents; Hydrogen-Ion Concentration; Kinetics; Pyridines; Spectrophotometry

A purple cactus pear (Opuntia ficus-indica) extract (CP) was encapsulated in double emulsions (DE) gelled with gelatin (DE-CP-G) and with gelatin and transglutaminase (DE-CP-GT), as well as in a DE with a liquid external aqueous phase (DE-CP), in order to study the retention of betanin as colorant agent. Both gelled DEs showed a predominantly elastic behavior, in contrast with DE-CP. The degradation rate constant of betanin was significantly higher in DE-CP-GT (90.2 x 10-3 days-1) than in DE-CP-G (11.0 x 10-3 days-1) and DE-CP (14.6 x 10-3 days-1) during cold-storage (4 °C). A shift towards yellow color was found in all the systems during cold-storage (4 °C) and after thermal treatment (70°C/30 min), especially in DE-CP-GT, denoting a higher degradation of betanin. Betalamic acid, cyclo-Dopa 5-O-β-glucoside, 17-decarboxy-betanin and neobetanin were identified by UHPLC-MS/MS as degradation products of betanin.

Topics: Betacyanins; Betalains; Chromatography, High Pressure Liquid; Emulsions; Fruit; Gels; Opuntia; Pigments, Biological; Plant Extracts; Pyridines; Tandem Mass Spectrometry; Transglutaminases

The biosynthesis of antioxidant pigments, namely, betalains, was believed to be restricted to Caryophyllales plants. This paper changes this paradigm, and enzyme mining from bacterial hosts promoted the discovery of bacterial cultures producing betalains. The spectrum of possible sources of betalain pigments in nature is broadened by our description of the first betalain-forming bacterium,

Topics: Betalains; Coloring Agents; Dioxygenases; Gluconacetobacter; Levodopa; Metabolic Networks and Pathways; Molecular Weight; Pigmentation; Pigments, Biological; Pyridines

The recent interest in plant pigment betalains as bioactive compounds and chemopreventive agents has led to the search for a reliable and scalable process to obtain them. The cloning of the novel and efficient enzyme 4,5-DOPA-extradiol dioxygenase from Gluconacetobacter diazotrophicus in an expression vector, and the subsequent heterologous expression in Escherichia coli cultures has led to the start-up of a biotechnological production system of individual pigments. The aim of this study was to search for the optimal conditions for the production of betalamic acid in microbial factories and the scaled-up obtention of the derived pigments. Four different betaxanthins and two betacyanins were obtained after the addition of non-transformable amines and amino acids and their condensation with the betalamic acid produced by the dioxygenase. The scaled-up obtention and purification of betalains improved the yields of the previous methodologies reaching quantities by up to 150 mg of pure compounds.

Topics: Betalains; Biotechnology; Biotransformation; Cloning, Molecular; Coloring Agents; Dioxygenases; Escherichia coli; Gene Expression; Gluconacetobacter; Metabolic Engineering; Pyridines

The key enzymatic step in betalain biosynthesis involves conversion of l-3,4-dihydroxyphenylalanine (l-DOPA) to betalamic acid. One class of enzymes capable of this is 3,4-dihydroxyphenylalanine 4,5-dioxygenase (DODA). In betalain-producing species, multiple paralogs of this gene are maintained. This study demonstrates which paralogs function in the betalain pathway and determines the residue changes required to evolve a betalain-nonfunctional DODA into a betalain-functional DODA. Functionalities of two pairs of DODAs were tested by expression in beets, Arabidopsis and yeast, and gene silencing was performed by virus-induced gene silencing. Site-directed mutagenesis identified amino acid residues essential for betalamic acid production. Beta vulgaris and Mirabilis jalapa both possess a DODA1 lineage that functions in the betalain pathway and at least one other lineage, DODA2, that does not. Site-directed mutagenesis resulted in betalain biosynthesis by a previously nonfunctional DODA, revealing key residues required for evolution of the betalain pathway. Divergent functionality of DODA paralogs, one clade involved in betalain biosynthesis but others not, is present in various Caryophyllales species. A minimum of seven amino acid residue changes conferred betalain enzymatic activity to a betalain-nonfunctional DODA paralog, providing insight into the evolution of the betalain pigment pathway in plants.

Topics: Arabidopsis; Arabidopsis Proteins; Beta vulgaris; Betalains; Caryophyllales; Dioxygenases; Evolution, Molecular; Gain of Function Mutation; Gene Expression Regulation, Plant; Levodopa; Mirabilis; Phylogeny; Pigmentation; Pigments, Biological; Plant Proteins; Plants, Genetically Modified; Pyridines; Yeasts

Health benefits of dietary phytochemicals have been suggested in recent years. Among 1000s of different compounds, Betalains, which occur in vegetables of the Cariophyllalae order (cactus pear fruits and red beet), have been considered because of reducing power and potential to affect redox-modulated cellular processes. The antioxidant power of Betalains is strictly due to the dissociation rate of the acid moieties present in all the molecules of this family of phytochemicals. Experimentally, only the pK a values of betanin were determined. Recently, it was evidenced it was evidenced as the acid dissociation, at different environmental pHs, affects on its electron-donating capacity, and further on its free radical scavenging power. The identical correlation was studied on another Betalains family compound, Betalamic Acid. Experimental evidences showed that the free radical scavenging capacity of this compound drastically decreases at pH > 5, but pK a values were experimentally not measured. With the aim to justify the Betalamic Acid behavior as free radical scavenger, in this paper we tried to predict in silico the pK a values by means different approaches. Starting from the known experimental pK as of acid compounds, both phytochemicals and small organic, two empirical approaches and quantum-mechanical calculation were compared to give reliable prediction of the pK as of Betalamic Acid. Results by means these computational approaches are consistent with the experimental evidences. As shown herein, in silico, the totally dissociated species, at the experimental pH > 5 in solution, is predominant, exploiting the higher electron-donating capability (HOMO energy). Therefore, the computational estimated pK a values of Betalamic Acid resulted very reliable.

Topics: Antioxidants; Betalains; Free Radical Scavengers; Models, Chemical; Pyridines

The comparative analysis of two Phytolacca americana DOPA dioxygenases (PaDOD1 and PaDOD2) that may be involved in betalain biosynthesis was carried out. The recombinant protein of PaDOD catalyzed the conversion of DOPA to betalamic acid, whereas DOD activity was not detected in PaDOD2 in vitro. The role of DOD genes is discussed in the evolutionary context using phylogenetic analysis, suggesting that DOD might have been duplicated early in evolution and that accumulation of base substitutions could have led to the different characteristics of DODs within the betalain-producing Caryophyllales.

Topics: Betalains; Dihydroxyphenylalanine; Dioxygenases; Phylogeny; Phytolacca americana; Plant Proteins; Plants; Pyridines

The biochemical analysis of Phytolacca americana DOPA dioxygenases (PaDOD1 and PaDOD2) was carried out. The recombinant protein of PaDOD1 catalyzed the conversion of DOPA to betalamic acid, whereas DOD activity was not detected in PaDOD2 in vitro. While the reported motif conserved in DODs from betalain-producing plants was found in PaDOD1, a single amino acid residue alteration was detected in PaDOD2. A mutated PaDOD1 protein with a change of 177 Asn to Gly showed reduced specific activity compared with PaDOD1, while DOPA dioxygenase activity was not observed for a mutated PaDOD2 protein which had its conserved motif replaced with that of PaDOD. A three-dimensional (3D) structural model of PaDOD1 and PaDOD2 showed that the conserved motif in DODs was located in the N-terminal side of a loop, which was found close to the putative active site. The difference in stability of the loop may affect the enzymatic activity of PaDOD2.

Topics: Amino Acid Motifs; Betalains; Dihydroxyphenylalanine; Dioxygenases; Models, Molecular; Phytolacca americana; Plant Proteins; Protein Structure, Tertiary; Pyridines

Betalains are plant pigments with high antioxidant and cancer chemopreventive properties used by the food industry as safe colorants. Betalains are restricted to species of the order Caryophyllales, and difficulty in obtaining individual molecules has limited their structural identification and application. This study was designed to develop a betalamic acid derivatized support generated from a primary amine polymer. The novel material presents color properties of a pseudobetaxanthin, and it is stable for at least 6 months. The bond formed can be displaced at mild conditions by the addition of amines in aqueous solutions over a broad pH range and at 25 °C. This releases the betalamic acid while forming the corresponding pigment. This one-step procedure significantly simplifies the process of obtaining semisynthetic betalains, and it is optimized here for the formation of betaxanthins and betacyanins derived from tyramine, dopamine, pyrrolidine, and indoline. The new method makes access to single betalains available to the entire scientific community and could stimulate research and applications in the field.

Topics: Antioxidants; Betalains; Pigments, Biological; Pyridines

A model betalainic dye was semisynthesized from betanin, the magenta pigment of the red beet, and was effective for live-cell imaging of Plasmodium-infected red blood cells. This water-soluble fluorescent probe is photostable, excitable in the visible region and cell membrane-permeable, and its photophysical properties are not notably pH-sensitive. Fluorescence imaging microscopy of erythrocytes infected with Plasmodium falciparum, a causative agent of malaria in humans, showed that only the parasite was stained. Z-stacking analysis suggested that the probe accumulates proximal to the nucleus of the parasite. Indicaxanthin, one of the natural fluorescent betalains found in the petals of certain flowers, did not stain the parasite or the red blood cell.

Topics: Animals; Betalains; Biomimetic Materials; Cell Survival; Coumarins; Erythrocytes; Fluorescent Dyes; Mice; Microscopy, Fluorescence; Molecular Imaging; Plasmodium falciparum; Pyridines

Betalains are synthesized in flowers, fruits and other tissues of the plant order Caryophyllales. Betalamic acid is the chromophore of betalain pigments synthesized by a ring-cleaving enzyme reaction on l-dihydroxyphenylalanine (DOPA). Although reverse genetic evidence has proven that DOPA 4,5-dioxygenase (DOD) is a key enzyme of betalain biosynthesis, all attempts to detect recombinant plant DOD activity in vitro have failed. Here, we report on the formation of betalamic acid from DOPA under suitable assay conditions using recombinant MjDOD produced by Escherichia coli. This is the first report showing biochemical evidence for DOD activity in vitro.

Topics: Betalains; Cloning, Molecular; DNA, Complementary; Escherichia coli; Gene Expression Regulation, Plant; Mirabilis; Molecular Sequence Data; Oxygenases; Plant Proteins; Pyridines; Recombinant Proteins

Betaxanthins are natural water-soluble yellow pigments present in plants of the order Caryophyllales. The native fluorescence of these compounds is extensively characterized in this work, with study of the fluorescent properties of 14 different betaxanthins. All the species showed a similar behavior, with excitation maxima between 463 and 475 nm and emission maxima between 506 and 515 nm. Thus, betaxanthins absorb light corresponding to the blue color and emit visible green light. Similarities in excitation and emission spectra point to the responsibility of betalamic acid in fluorescence. The influence of the amine moiety is discussed. For the first time fluorescent properties of betaxanthins are applied to the detection of these pigments after separation by high-performance liquid chromatography. Wavelengths used were 460 nm for excitation and 510 nm for emission, which were suitable for detecting the native fluorescence of all the pigments assayed. Calibration was performed in each case and it exhibited linearity within the range considered, at least 20 microM. The lowest detection limit was 100 nM, corresponding to betaxanthins derived from methionine sulfoxide and leucine. Fluorescence detection was applied to the quantification of betaxanthins present in Carpobrotus acinaciformis. The present work opens up new possibilities for the analysis of betaxanthins by improving existing protocols through fluorescence detection.

Topics: Betacyanins; Betalains; Caryophyllaceae; Chromatography, High Pressure Liquid; Indoles; Magnoliopsida; Picolinic Acids; Pyridines; Spectrometry, Fluorescence

Betaxanthins, the yellow-orange water-soluble pigments from yellow beet (Beta vulgaris ssp. vulgaris cv. Bejo Zaden) and cactus pear (Opuntia ficus-indica cv. Gialla) have been investigated using an HPLC system compatible with mass spectrometry. Five novel betaxanthins were found and characterized as the immonium adducts of betalamic acid with serine, gamma-aminobutyric acid, valine, isoleucine, and phenylalanine. To enable concentration of betalain samples, desalting was performed by solid-phase extraction. With this technique, betacyanins could be separated from the betaxanthins using the pH-dependent retention characteristics of red and yellow betalains. The betaxanthin fraction was taken for the preparation of betalamic acid as a precursor for semisynthetic standards. The HPLC method was applied to yellow beet and cactus pear, revealing a more complex betalain profile than described earlier, thus proving its suitability for screening of betaxanthin-containing plants as potential sources for natural food colors.

Topics: Beta vulgaris; Betacyanins; Betalains; Chromatography, High Pressure Liquid; Food Coloring Agents; Indoles; Opuntia; Pigments, Biological; Pyridines; Quaternary Ammonium Compounds; Spectrometry, Mass, Electrospray Ionization