Betalains, the nature-inspired pigments, in health and diseases

5-Hydroxymaltol Derived from Beetroot Juice through Lactobacillus Fermentation Suppresses Inflammatory Effect and Oxidant Stress via Regulating NF-kB, MAPKs Pathway and NRF2/HO-1 Expression

Inflammation is the first response of the immune system against bacterial pathogens. This study isolated and examined an antioxidant derived from Lactobacillus fermentation products using cultured media with 1% beet powder. The antioxidant activity of the beet culture media was significantly high. Antioxidant activity-guided purification and repeated sample isolation yielded an isolated compound, which was identified as 5-hydoxymaltol using nuclear magnetic resonance spectrometry. We examined the mechanism of its protective effect on lipopolysaccharide (LPS)-induced inflammation of macrophages. 5-Hydroxymaltol suppressed nitric oxide (NO) production in LPS-stimulated RAW 264.7 cells. It also suppressed tumor necrosis factor α (TNF-α), interleukin (IL)-1β, and inducible nitric oxide synthase (iNOS) in the messenger RNA and protein levels in LPS-treated RAW 264.7 cells. Moreover, it suppressed LPS-induced nuclear translocation of NF-κB (p65) and mitogen-activated protein kinase activation. Furthermore, 5-hydroxymaltol reduced LPS-induced reactive oxygen species (ROS) production as well as increased nuclear factor erythroid 2-related factor 2 and heme oxygenase 1 expression. Overall, this study found that 5-hydroxymaltol has anti-inflammatory activities in LPS-stimulated RAW 264.7 macrophage cells based on its inhibition of pro-inflammatory cytokine production depending on the nuclear factor κB signaling pathway, inhibition of LPS-induced reactive oxygen species production, inhibition of LPS-induced mitogen-activated protein kinase induction, and induction of the nuclear factor erythroid 2-related factor 2/heme oxygenase 1 signaling pathway. Our data showed that 5-hydroxymaltol may be an effective compound for treating inflammation-mediated diseases.

Ability of Yeast Metabolic Activity to Reduce Sugars and Stabilize Betalains in Red Beet Juice

To lower the risk of obesity, diabetes, and other related diseases, the WHO recommends that consumers reduce their consumption of sugars. Here, we propose a microbiological method to reduce the sugar content in red beet juice, while incurring only slight losses in the betalain content and maintaining the correct proportion of the other beet juice components. Several yeast strains with different metabolic activities were investigated for their ability to reduce the sugar content in red beet juice, which resulted in a decrease in the extract level corresponding to sugar content from 49.7% to 58.2%. This strategy was found to have the additional advantage of increasing the chemical and microbial stability of the red beet juice. Only slight losses of betalain pigments were noted, to final concentrations of 5.11% w/v and 2.56% w/v for the red and yellow fractions, respectively.

Betalain exerts cardioprotective and anti-inflammatory effects against the experimental model of heart failure

Betalain is a natural plant pigment known to elicit various biological activities. However, studies on the protective effect of betalain against heart failure have not reported yet. The experimental model of heart failure was created in Wistar rats using isoproterenol (ISO). The animals were randomly assigned into four groups such as sham-control, ISO-induced heart failure, betalain pretreated before ISO induction (50 mg/kg/day), and betalain drug control group were maintained for 6 weeks. At the end of the experimental period, anti-oxidant enzymes, inflammatory markers, matrix proteins, cardiac-specific markers, and micro RNAs were elucidated using RT-PCR, and ELISA analysis. The results demonstrated that the rats induced with ISO displayed an abnormality in cardiac functions, increased oxidative stress markers (p < 0.01), inflammatory cytokines (p < 0.01) while abrogated the expression of miR-18a, and increased miR-199a. While betalain pre-treated rats prevented the cardiac failure significantly (p < 0.01) with improved anti-oxidant enzymes, abrogated the inflammatory signals with restored matrix proteins, cardiac biomarker genes, and attenuated miR-423 and miR-27 compared to heart failure rats. The results of the study suggest that the betalain treatment protected the hearts from failing via microRNA mediated activation the anti-inflammatory signaling and restoring the matrix protein modulation.

Current Knowledge on Beetroot Bioactive Compounds: Role of Nitrate and Betalains in Health and Disease

An increase in the prevalence of noncommunicable chronic diseases has been occurring in recent decades. Among the deaths resulting from these conditions, cardiovascular diseases (CVD) stand out as the main contributors. In this regard, dietary patterns featuring a high content of vegetables and fruits, such as the Mediterranean and the DASH diets, are considered beneficial, and thus have been extensively studied. This has resulted in growing interest in vegetable-derived ingredients and food-supplements that may have potential therapeutic properties. Among these supplements, beetroot juice, which is obtained from the root vegetable Beta vulgaris, has gained much attention. Although a significant part of the interest in beetroot juice is due to its nitrate (NO₃^-) content, which has demonstrated bioactivity in the cardiovascular system, other ingredients with potential beneficial properties such as polyphenols, pigments and organic acids are also present. In this context, the aim of this review article is to analyze the current knowledge regarding the benefits related to the consumption of beetroot and derived food-supplements. Therefore, this article focuses on nitrate and betalains, which are considered to be the major bioactive compounds present in beetroot, and thus in the derived dietary supplements.

Effects of raw red beetroot consumption on metabolic markers and cognitive function in type 2 diabetes patients

OBJECTIVES

This study aimed to investigate the effects of raw red beetroot consumption on metabolic markers and cognitive function in type 2 diabetes patients.

METHODS

In a quasi-experimental study, 44 type 2 diabetes patients (57 ± 4.5 years) consumed raw red beetroot (100 g, daily), for 8 weeks. Metabolic markers including body weight, glucose and lipid profile parameters, inflammatory and oxidative stress markers, paraoxonase-1 activity, hepatic enzymes, blood pressure and cognitive function were measured at the beginning and end of 8 weeks.

RESULTS

Raw red beetroot consumption resulted in a significant decrease in fasting blood sugar (FBS) levels (-13.53 mg/dL), glycosylated hemoglobin (HbA1c)(-0.34%), apolipoproteinB100 (ApoB100) (-8.25 mg/dl), aspartate aminotransferase (AST) (-1.75 U/L), alanine aminotransferase (ALT) (-3.7 U/L), homocysteine (-7.88 μmol/l), systolic (-0.73 mmHg) and diastolic blood pressure (-0.34 mmHg), anda significant increase in total antioxidant capacity (TAC) (105 μmol/L) and cognitive function tests (all P values <0.05). Other variables did not change significantly after the intervention.

CONCLUSIONS

Raw red beetroot consumption for 8 weeks in T2DM patients has beneficial impacts on cognitive function, glucose metabolism and other metabolic markers.

A bioinspired nitrone precursor to a stabilized nitroxide radical

Nitrones derived from natural antioxidants are emerging as highly specific therapeutics against various human diseases, including stroke, neurodegenerative pathologies, and cancer. However, the development of useful pseudo-natural nitrones requires the judicious choice of a secondary metabolite as the precursor. Betalains are nitrogen-containing natural pigments that exhibit marked antioxidant capacity and pharmacological properties and, hence, are ideal candidates for designing multifunctional nitrones. In this work, we describe the semisynthesis and properties of a biocompatible and antioxidant betalain-nitrone called OxiBeet. This bio-based compound is a better radical scavenger than ascorbic acid, gallic acid, and most non-phenolic antioxidants and undergoes concerted proton-coupled electron transfer. The autoxidation of OxiBeet produces a persistent nitroxide radical, which, herein, is studied via electron paramagnetic resonance spectroscopy. In addition, femtosecond transient absorption spectroscopy reveals that excited state formation is not required for the oxidation of OxiBeet. The results are compared with those obtained using betanin, a natural betalain, and pBeet, the imine analog of OxiBeet. The findings of this study will enable the development of antioxidant and spin-trap nitrones based on the novel N-oxide 1,7-diazaheptamethinium scaffold and betalain dyes with enhanced hydrolytic stability in aqueous alkaline media.

Comparative evaluation of different methods for determining phytochemicals and antioxidant activity in products containing betalains - Verification of beetroot samples

This study presents methods that can be used to assess the health quality of products containing betalains. The paper compares and verifies data on the phytochemical composition of three different pigmented beetroot cultivars using spectrophotometric, HPLC-DAD, HPTLC and LC-Q-Orbitrap-HRMS techniques. Additionally, we compared the total antioxidant activity in both the cell-free and cellular systems. Betalain contribution to antioxidant activity was also determined using post-column derivatization and it was found that in the case of red beetroot it is about 50%. Photometric measurements are recommended for a simple and inexpensive analysis of the total betacyanin and betaxanthin content. Liquid chromatography techniques produced more precise information on phytochemical composition in the tested samples. The combination of liquid chromatography with high-resolution mass spectrometry produced the largest amount of quantitative and qualitative data; in beetroot samples sixty-four phytochemicals have been identified therefore, this approach is recommended for more detailed metabolomics studies.

Biological Properties and Applications of Betalains

Betalains are water-soluble pigments present in vacuoles of plants of the order Caryophyllales and in mushrooms of the genera Amanita, Hygrocybe and Hygrophorus. Betalamic acid is a constituent of all betalains. The type of betalamic acid substituent determines the class of betalains. The betacyanins (reddish to violet) contain a cyclo-3,4-dihydroxyphenylalanine (cyclo-DOPA) residue while the betaxanthins (yellow to orange) contain different amino acid or amine residues. The most common betacyanin is betanin (Beetroot Red), present in red beets Beta vulgaris, which is a glucoside of betanidin. The structure of this comprehensive review is as follows: Occurrence of Betalains; Structure of Betalains; Spectroscopic and Fluorescent Properties; Stability; Antioxidant Activity; Bioavailability, Health Benefits; Betalains as Food Colorants; Food Safety of Betalains; Other Applications of Betalains; and Environmental Role and Fate of Betalains.

Imine chemistry in plant metabolism

Imine chemistry represents an important category of chemical reactions involved in the biosynthesis of plant natural products, ranging from the newly discovered mobile defense hormone N-hydroxy-pipecolic acid to the red-to-yellow tyrosine-derived betalain pigments. Spontaneous imine formation reactions have also served as the basis for the evolution of numerous plant metabolic enzymes, such as specialized Pictet-Spenglerases that produce the backbone structures of benzylisoquinoline and monoterpene indole alkaloids and pyridoxal 5'-phosphate-dependent enzymes of diverse functions. Here, we review occurrences of imine chemistry in plant metabolism and their chemical and biochemical mechanisms. A better understanding of plant imine chemistry will ultimately facilitate synthetic biology approaches to further expand the scope of imine natural product biosynthesis for broad biotechnological applications.

Recent developments in emerging technologies for beetroot pigment extraction and its food applications

Beetroot is well known for its deep red-purple colouring pigments called betalains. Betalains also found its application in the preparation of functional foods and drinks. Therefore, extraction of pigments with higher recovery and stability is the prime need for the industry. Conventional extraction techniques such as maceration, grinding or pressing have reported low yield of betalains and required large volume of solvent and energy. On the other hand, emerging technologies such as ultrasound, microwave and pulse electric field techniques are highly efficient processes and can achieve higher recovery. In this regard, this review provides an in-depth discussion on the various extraction methods and factors affecting the stability of betalains using conventional and emerging technologies. The recent applications of pigments in various food systems are also presented. Finally, challenges and future prospects of extraction and application of beetroot pigment have been identified and discussed.

Functional relationship of vegetable colors and bioactive compounds: Implications in human health

Vegetables are essential protective diet ingredients that supply ample amounts of minerals, vitamins, carbohydrates, proteins, dietary fiber, and various nutraceutical compounds for protection against various disease conditions. Color is the most important quality parameter for the farmers to access the harvest maturity while for the consumer's reliable indices to define acceptability or rejection. The colored vegetables contain functional compounds like chlorophylls, carotenoids, betalains, anthocyanins, etc. well recognized for their antioxidant, antimicrobial, hypolipidemic, neuroprotective, antiaging, diuretic, and antidiabetic properties. Recently, there has been a shift in food consumption patterns from processed to semi-processed or fresh fruits and vegetables to ensure a healthy disease-free life. This shifted the focus of agriculture scientists and food processors from food security to nutrition security. This has resulted in recent improvements to existing crops like blue tomato, orange cauliflower, colored and/or black carrots, with improved color, and thus enriched bioactive compounds. Exhaustive laboratory trials though are required to document and establish their minimum effective concentrations, bioavailability, and specific health benefits. Efforts should also be directed to breed color-rich cultivars or to improve the existing varieties through conventional and molecular breeding approaches. The present review has been devoted to a better understanding of vegetable colors with specific health benefits and to provide in-hand information about the effect of specific pigment on body organs, the effect of processing on their bioavailability, and recent improvements in colors to ensure a healthy lifestyle.

Red beet (Beta vulgaris) betalains and grape (Vitis vinifera) anthocyanins as colorants in white currant juice - Effect of storage on degradation kinetics, color stability and sensory properties

Red beet betalains, grape anthocyanins, and their mixtures were used as colorants in white currant juice. Storage stability of the compounds was evaluated using liquid chromatography and the degradation kinetic order and parameters were calculated. Degradation of betalains followed first-order kinetics, while the degradation of anthocyanins did not have any trend toward any order kinetics. The coexisting anthocyanins and their concentration affected the rate constant of betalains. Betalains degraded faster than anthocyanins, their mixtures promoted respective degradation. Pyruvate derivatives of anthocyanins showed better stability. During storage, all samples became more yellowish with CIELab method and lighter in color. In the projective mapping sensory test, samples were distinguished by the colorant type as the main criteria and the storage time as the second criteria. Anthocyanin (described as 'dark' and 'natural') was preferred by sensory panelists over betalain (described as 'pink' and 'unnatural'), as were the fresh samples over stored samples.

Red Beetroot Betalains: Perspectives on Extraction, Processing, and Potential Health Benefits

In recent years, red beetroot has received a growing interest due to its abundant source of bioactive compounds, particularly betalains. Red beetroot betalains have great potential as a functional food ingredient employed in the food and medical industry due to their diverse health-promoting effects. Betalains from red beetroot are natural pigments, which mainly include either yellow-orange betaxanthins or red-violet betacyanins. However, betalains are quite sensitive toward heat, pH, light, and oxygen, which leads to the poor stability during processing and storage. Therefore, it is necessary to comprehend the impacts of the processing approaches on betalains. In this review, the effective extraction and processing methods of betalains from red beetroot were emphatically reviewed. Furthermore, a variety of recently reported bioactivities of beetroot betalains were also summarized. The present work can provide a comprehensive review on both conventional and innovative extraction techniques, processing methods, and the stability of betalains.

Cactus: Chemical, nutraceutical composition and potential bio-pharmacological properties

Cactus species are plants that grow in the arid and semiarid regions of the world. They have long fascinated the attention of the scientific community due to their unusual biology. Cactus species are used for a variety of purposes, such as food, fodder, ornamental, and as medicinal plants. In the last regard, they have been used in traditional medicine for eras by the ancient people to cure several diseases. Recent scientific investigations suggest that cactus materials may be used as a source of naturally-occurring products, such as mucilage, fiber, pigments, and antioxidants. For this reason, numerous species under this family are becoming endangered and extinct. This review provides an overview of the habitat, classification, phytochemistry, chemical constituents, extraction and isolation of bioactive compounds, nutritional and pharmacological potential with pre-clinical and clinical studies of different Cactus species. Furthermore, conservation strategies for the ornamental and endangered species have also been discussed.

Betanin as a multipath oxidative stress and inflammation modulator: a beetroot pigment with protective effects on cardiovascular disease pathogenesis

Oxidative stress is a common physiopathological condition enrolled in risk factors for cardiovascular diseases. Individuals in such a redox imbalance status present endothelial dysfunctions and inflammation, reaching the onset of heart disease. Phytochemicals are able to attenuate the main mechanisms of oxidative stress and inflammation and should be considered as supportive therapies to manage risk factors for cardiovascular diseases. Beetroot (Beta vulgaris L.) is a rich source of bioactive compounds, including betanin (betanidin-5-O-β-glucoside), a pigment displaying the potential to alleviate oxidative stress and inflammantion, as previously demonstrated in preclinical trials. Betanin resists gastrointestinal digestion, is absorbed by the epithelial cells of intestinal mucosa and reaches the plasma in its active form. Betanin displays free-radical scavenger ability through hydrogen or electron donation, preserving lipid structures and LDL particles while inducing the transcription of antioxidant genes through the nuclear factor erythroid-2-related factor 2 and, simultaneously, suppressing the pro-inflammatory nuclear factor kappa-B pathways. This review discusses the anti-radical and gene regulatory cardioprotective activities of betanin in the pathophysiology of endothelial damage and atherogenesis, the main conditions for cardiovascular disease. In addition, betanin influences on these multipath cellular signals and aiding in reducing cardiovascular disorders is proposed.

Therapeutic Application of Betalains: A Review

Anthocyanins, betalains, riboflavin, carotenoids, chlorophylls and caramel are the basic natural food colorants used in modern food manufacture. Betalains, which are composed of red–violet betacyanin and yellow betaxanthins, are water-soluble pigments that color flowers and fruits. Betalains are pigments primarily produced by plants of the order Caryophyllales. Because of their anti-inflammatory, cognitive impairment, anticancer and anti-hepatitis properties, betalains are useful as pharmaceutical agents and dietary supplements. Betalains also exhibit antimicrobial and antimalarial effects, and as an example, betalain-rich Amaranthus spinosus displays prominent antimalarial activity. Studies also confirmed the antidiabetic effect of betalains, which reduced glycemia by 40% without causing weight loss or liver impairment. These findings show that betalain colorants may be a promising alternative to the synthetic dyes currently used as food additives.

Relationship between color and betalain content in different thermally treated beetroot products

Several health benefits are currently attributed to natural pigments that give fruit and vegetables their inherently colorful properties. Color measurements might therefore serve as quick indicators of the potential health-promoting properties of such foods. Nevertheless, the relationship between color and pigment content depends on the type of matrix and pigment, as well as the factors affecting their interaction, which calls for further investigation. Hence, the aim of the present study is to investigate the relationship between color parameters and betalain content in three commonly consumed beetroot products (beetroot juice, beetroot puree and whole beetroot), subjected to thermal treatment. Our results showed a negative correlation between the total betalain content and the color parameters L*, a*, b*, chroma, and hue angle in beetroot juice, beetroot puree and whole beetroot. Two chromatic parameters, a* and chroma, are proposed as the best descriptors for the betalain concentrations of these products. Likewise, the tristimulus L/ab combination for the juice is also suggested as a good descriptor. Our findings highlighted that the relationship between color and total betalain content depended on the beetroot product under assessment, with the strongest correlations found for the juice. Squeezed beetroot was therefore suggested as an alternative to improve this relationship in more complex matrices such as whole cooked beetroots. Useful information from color determination sheds light on the relationship between color and betalain pigments in beetroot, suggesting that color determination could be used as an indicator of betalain content.

Metabolic Engineering of Escherichia coli for de Novo Production of Betaxanthins

Betalains are emerging natural pigments with high tinctorial strength and stability, physiological activities, and fluorescent properties for potential application in food, cosmetic, and pharmaceutical industries. Betalains including yellow betaxanthins and red betacyanins are mainly restricted in the Caryophyllales plants. To expand the availability of individual betaxanthins, here, we constructed an Escherichia coli BTA6 for de novo biosynthesis of betalamic acid. Using this strain as a monoculture platform, 14 yellow and 2 red betaxanthins were produced by feeding amino acids and amines. Furthermore, we constructed an l-histidine overproducing strain using chromosome engineering to deattenuate regulation and established a coculture system. After optimization of the initial inoculation ratios and fermentation conditions, the compatible and robust coculture system produced 287.69 mg/L of histidine-betaxanthin. This is the first report on de novo production of betaxanthins in engineered E. coli using glucose as a carbon source. Our work highlights the feasibility of microbial cell factories to produce individual betalains.

The effects of betalain-rich cacti (dragon fruit and cactus pear) on endothelial and vascular function: a systematic review of animal and human studies

Dragon fruit (Hylocereus) and cactus pear (Opuntia) are cacti species that have been widely used globally as a reliable source of food as well as traditional folk remedies. They have become of scientific interest recently due to their high levels of bioactive phytochemical compounds, in particular betalains. Earlier systematic reviews have explored the impact of supplementation of these cactus species on obesity, type-2 diabetes mellitus and cardiovascular risk factors: body weight and composition, serum triglycerides, cholesterol, blood glucose and blood pressure. However, effects on vascular health and endothelial function have yet to be reviewed. In order to address this gap in the literature, a systematic review has been conducted to evaluate the physiological effects of Hylocereus and Opuntia cacti on endothelial and vascular function in in vivo animal models and human studies. An electronic search was performed in the following databases: PubMed (MEDLINE), EMBASE (via Ovid), CINAHL, Scopus, Web of Science®, and The Cochrane Library (CENTRAL). All journals were searched since inceptions up to January 2020 without language restriction. Outcomes of interest were blood pressure, arterial stiffness, vascular reactivity and biochemical markers of endothelial dysfunction. Two investigators independently performed the study selection and data extraction. From 394 references, only 16 studies (9 animal and 7 human) fulfilled the eligibility criteria. Animal studies suggested a potential increase in vasodilation and serum nitric oxide and a reduction in vascular stiffness and blood pressure. The small number of human studies showed a reduction in heart rate as well as an increase in heart rate variability. Although these findings appear to indicate improvement in vascular health, there is a severe lack of robust, randomised human intervention studies to identify underlying mechanisms, optimal dose and long-term effects of cacti consumption.

Antitumoral Drug Potential of Tryptophan-Betaxanthin and Related Plant Betalains in the Caenorhabditis elegans Tumoral Model

Betalains are plants pigments identified as potent antioxidant molecules, naturally present in foods like beetroot and prickly pears. Although activities described for betalain-containing formulations include cancer prevention and treatment, the use of extracts instead of purified pigments has avoided the investigation of the real chemopreventive and chemotherapeutic potential of these phytochemicals. Three betalain-rich extracts and six individual pure betalains were used in this work to characterize the activity and to explore possible molecular mechanisms. The animal model Caenorhabditis elegans (tumoral strain JK1466) was used to evaluate the effect of betalains as chemotherapeutics drugs. An objective evaluation method of tumor growth in C. elegans has been developed to assess the possible antitumoral activity of the different treatments. This protocol allowed a fast and reliable screening of possible antitumoral drugs. Among the betalains tested, tryptophan-betaxanthin reduced tumor size by 56.4% and prolonged the animal’s lifespan by 9.3%, indicating high effectiveness and low toxicity. Structure–activity relationships are considered. Assays with mutant strains of C. elegans showed that the mechanism underlying these effects was the modulation of the DAF-16 transcription factor and the insulin signaling pathway. Our results indicate that tryptophan-betaxanthin and related betalains are strong candidates as antitumoral molecules in cancer treatment.

Inhibitory Effect of Betanin FromHylocereus ocamponisAgainst Steatohepatitis in Mice Fed a High-Fat Diet

Betanin is a phytocompound whose effect in steatohepatitis has not yet been tested. Betanin was extracted from the fruits of Hylocereus ocamponis, and its effects were evaluated in a mice model for non-alcoholic fatty liver disease. Six-week-old male BALB/c mice fed with a high-fat diet received 9.6 mg of betanin per day during 40 days. Body, liver, and epididymal fat pad weights and the levels of blood serum total cholesterol, triglycerides, high-density lipoproteins, alanine aminotransferase, blood nitrogen urea, creatinine, and total antioxidant capacity were measured. Hepatosteatosis and inflammatory infiltration were categorized, and the relative cell area of hepatocytes was determined. Betanin inhibited the inflammatory infiltration of the liver ( P = 4.000 × 10−6) and the necrosis of hepatocytes ( P = 9.634 × 10−7); it also produced a predominance of microvesicular steatosis ( P = 9.634 × 10−7), decreased epididymal fat pad weight ( P = 8.250 × 10−4), and increased blood serum total cholesterol ( P = 0.011). Betanin is a promising compound for fatty liver, steatohepatitis, and chronic liver disease.

Betalain exerts a protective effect against glaucoma is majorly through the association of inflammatory cytokines

The present research aimed at evaluating the protective role of betalain on the in vitro glaucoma model using PC12 neuronal cells. The cultured neuronal cells in a customized pressurized chamber were analyzed for the onset of glutathione, myeloperoxidase (MPO), cathepsin, expression of inflammatory enzymes such as cyclooxygenase (COX-1), lipoxygenase (5- LOX), sPLA2 caveolin-1, glaucoma markers and other inflammatory cytokines in the presence and absence of betalain. The results have shown that a significant increase in the expression of oxidative stress with increased activity of cathepsin B and D. On the other hand, the activity of inflammatory enzymes such as COX-1, 5- LOX, sPLA2 were significantly increased in pressure exposed cells. In addition, glaucoma simulated cells demonstrated a significant increase in the VEGF, TGF-β, BDGF, and neuroserpin compared to control. Moreover, cells predisposed to hydrostatic pressure demonstrated an increase in (p < 0.01) inflammatory cytokines such as IL-6, CXCR4, IL-17, IL-1β, and TNF-α levels. However, cells pre-treated with betalain improved the glutathione levels with attenuated MPO activity. Simultaneously, the levels of inflammatory cytokines and other glaucoma marker genes found restored in drug pre-treated cells. Thus, the results of the present study demonstrate that the use of betalain on ocular cells can prevent the progression of the disease that can be a suggestive therapeutic for controlling glaucoma like conditions.

Betavulgarin Isolated from Sugar Beet (Beta vulgaris) Suppresses Breast Cancer Stem Cells through Stat3 Signaling

Breast cancer is a major health problem that affects lives worldwide. Breast cancer stem cells (BCSCs) are small subpopulations of cells with capacities for drug resistance, self-renewal, recurrence, metastasis, and differentiation. Herein, powder extracts of beetroot were subjected to silica gel, gel filtration, thin layer chromatography (TLC), and preparatory high-pressure liquid chromatography (HPLC) for isolation of one compound, based on activity-guided purification using tumorsphere formation assays. The purified compound was identified as betavulgarin, using nuclear magnetic resonance spectroscopy and electrospray ionization (ESI) mass spectrometry. Betavulgarin suppressed the proliferation, migration, colony formation, and mammosphere formation of breast cancer cells and reduced the size of the CD44⁺/CD24⁻ subpopulation and the expression of the self-renewal-related genes, C-Myc, Nanog, and Oct4. This compound decreased the total level and phosphorylated nuclear level of signal transducer and activator of transcription 3 (Stat3) and reduced the mRNA and protein levels of sex determining region Y (SRY)-box 2 (SOX2), in mammospheres. These data suggest that betavulgarin inhibit the Stat3/Sox2 signaling pathway and induces BCSC death, indicating betavulgarin might be an anticancer agent against breast cancer cells and BCSCs.

Identification of Novel Low-Weight Sulfhydryl Conjugates of Oxidized 5-O- and 6-O-Substituted Betanidin Pigments

The formation of conjugates of oxidized betacyanin pigments with selected low-weight sulfhydryl scavengers was studied. Short-lived quinonoids, quinone methides, and aminochromes derived from oxidized betacyanins are able to form adducts with different efficiencies. In this report, mass spectrometric and NMR identifications of CS-linked conjugates of cysteine, cysteamine, N-acetylcysteine, and dl-dithiolthreitol with quinonoid forms generated through oxidation of betanidin, betanin, and gomphrenin is presented. An adduct that formed between cysteine and quinonoid generated from betanin by its oxidation and decarboxylation (2-decarboxy-xanbetanin) was detected and reported for the first time. The most stable gomphrenin CS-conjugate, N-acetylcysteinylated gomphrenin, was isolated by semipreparative chromatography and its structure was established by NMR analysis. This enabled to confirm the conjugation position at carbon C-4 and to indicate the presence of a dopachromic intermediate during oxidation of gomphrenin. Conjugation of betacyanins with thiol-bearing moieties may generate new molecules with modified chemical and biological properties. Obtained results confirm that gomphrenin is capable of forming CS-conjugates with higher efficiency than betanin.

Natural Pigments of Anthocyanin and Betalain for Coloring Soy-Based Yogurt Alternative

The aim of this work was to evaluate the color stability of betalain- and anthocyanin-rich extracts in yogurt-like fermented soy, in order to develop a preliminary understanding of how these pigments behave in this type of food system during storage for 21 days at 4 °C. Thus, the extracts of red beetroot, opuntia, hibiscus and red radish were integrated into the yogurt-like fermented soy in two different ways-directly after lyophilization, and encapsulated in nanosystems based in soybean lecithin-as this approach has never been used to further increase the value and potential of the dairy-free alternatives of yogurt-like fermented soy. The results showed that non-encapsulated betalain-rich extracts from red radish are the most promising for coloring yogurt-like fermented soy. However, encapsulated opuntia extracts can also be an alternative to supplement the soy fermented beverages with betalains, without changing significantly the color of the system but giving all its health benefits, due to the protection of the pigments by nanoencapsulation.

A review on bioactive compounds of beet (Beta vulgaris L. subsp. vulgaris) with special emphasis on their beneficial effects on gut microbiota and gastrointestinal health

This review discusses the available literature concerning the bioactive compounds of beet (Beta vulgaris L.) and their ability to modulate the gut microbiota and parameters indicative of gastrointestinal health. Data of published literature characterize beet as a source of a variety of bioactive compounds (e.g. diet fiber, pectic-oligosaccharides, betalains and phenolics) with proven beneficial effects on human health. Beet extracts and pectin and pectic-oligosaccharides from beet have shown able to modulate positively gut microbiota composition and activity, with noticeable bifidogenic effects, in addition to stimulate the growth and metabolism of probiotics. Beet betalains and phenolics seem to increase the production of metabolites (e.g. short chain fatty acids) by gut microbiota and probiotics, which are linked with different beneficial effects on host health. The outstanding contents of betalains and phenolics with antioxidant, anti-inflammatory and anti-carcinogenic properties have been linked to the positive effects of beet on gastrointestinal health. Beet should be a healthy choice for use in domestic meal preparations and a source of ingredients to formulate added-value functionalized food products.

Effects of betalains on atherogenic risk factors in patients with atherosclerotic cardiovascular disease

This study evaluated the potential impacts of supplementation with betalain-rich extracts of foods on some atherosclerotic risk factors in coronary artery disease patients. During an acute phase, 48 male patients received about 50 mg betalain/betacyanin, and their blood and urine samples were collected at 3, 8, and 24 hours after supplementations. Also, in a pilot randomized crossover trial, these participants were allocated to two-week interventions (a betacyanin-rich supplement of Opuntia stricta, a betalain-rich supplement of red beetroot and a placebo) with two-week washout periods. Then, their plasma samples were collected at the baseline after a two-week period. The concentrations of betanin in plasma and urine samples were determined using HPLC. Also, homocysteine and glucose levels, lipid profile, and blood pressure were analyzed. Additionally, quality of life and dietary intake were assessed. After these interventions, minimal amounts of betanin were found in plasma and about 0.13-0.93% in urine. Also, both supplements significantly decreased the concentration of homocysteine, glucose, total cholesterol, triglyceride, and LDL. Also, betalain-rich supplements lowered both systolic and diastolic blood pressures. Nevertheless, the clinically meaningful changes were only found in the case of Hcy, LDL, and non-HDL-c concentrations. It seems that food sources of betalains can be considered as functional foods because they improve the lipid profile and levels of homocysteine, glucose, blood pressure, and quality of life to some extent.

Effect of Betanin, a Beetroot Component, on Vascular Tone in Isolated Porcine Arteries

BACKGROUND

Beetroot has attracted much attention because of its blood pressure-lowering properties. Although beetroot contains various nutritional compounds, including inorganic nitrate, some of their physiological properties are not fully understood. In this study, we examined whether betanin, a beetroot component, has a regulatory effect on vascular tone.

METHODS

Mechanical responses of isolated porcine coronary, mesenteric, and pulmonary arteries were assessed by organ chamber technique. In some cases, the vascular reactivity was observed in the presence of a physiological concentration of betanin (10 µM).

RESULTS

Betanin did not induce vasorelaxation at physiological concentrations both in endothelium-intact and -denuded coronary, mesenteric, and pulmonary arteries. The endothelium-dependent agonists, bradykinin and A23187 induced vasorelaxation of endothelium-intact coronary arteries, both of which were not affected by exposure to betanin. Likewise, endothelium-independent vasorelaxation induced by sodium nitrite and sodium nitroprusside was also not affected by the presence of betanin. In addition, exposure of endothelium-intact coronary arteries to betanin did not attenuate prostaglandin F2α- and endothelin-1-induced vasocontraction.

CONCLUSIONS

These findings suggest that betanin does not have a vasorelaxant activity. It is unlikely that betanin is a component directly responsible for the beetroot-induced acute blood pressure-lowering effect in a nitrate-independent manner.

Biological effects of red beetroot and betalains: A review

Over the past few years, the use of natural substances as protective or therapeutic agents has gained much attention worldwide. Recent modern studies have shown a variety of health benefits for red beetroot and its active compounds betalains (also betanin) such as antioxidative, anti-inflammation, anticancer, blood pressure and lipid lowering, also antidiabetic and anti-obesity effects. Betanin, the main component of the red beetroot, is a betalain glycosidic pigment, which is used as a food additive. This review summarizes findings in the literature and shows the therapeutic potential of red beetroot and its active compounds (betalains) as promising alternatives for supplemental therapies in multiple diseases.

Metabolic engineering of rice endosperm for betanin biosynthesis

Betanin has been widely used as an additive for many centuries, and its use has increased because of its market application as an additive, high free radical scavenging activity, and safety, health-promoting properties. The main source of betanin is red beet, but many factors notably affect the yield of betanin from red beets. Betanin is not produced in cereal grains. Thus, developing biofortified crops with betanin is another alternative to health-promoting food additives. Here, rice endosperm was bioengineered for betanin biosynthesis by introducing three synthetic genes (meloS, BvDODA1S, and BvCYP76AD1S). The overexpression of these genes driven by rice endosperm-specific promoter established the betanin biosynthetic pathways in the endosperm, resulting in new types of germplasm - 'Betanin Rice' (BR). The BR grains were enriched with betanin and had relatively high antioxidant activity. Our results proved that betanin can be biosynthesized de novo in rice endosperm by introducing three genes in the committed betanin biosynthetic pathway. The betanin-fortified rice in this study can be used as a functional grain to promote health and as a raw material to process dietary supplements.

Antioxidant and Antimicrobial Properties of Semi-Processed Frozen Prickly Pear Juice as Affected by Cultivar and Harvest Time

Consumer interest toward natural ingredients is creating a growing trend in the food industry and research for the development of natural products such as colorants, antimicrobials and antioxidants. Semi-processed frozen prickly pear (Opuntia ficus-indica (L.) Mill.) juices (PPJs), obtained from three cultivars with white, red and yellow pulp, with different harvest times ("Agostani" and "Bastardoni"), were characterized for betalains, total phenolics, flavonoids, carotenoids, antioxidant capacity (by 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH)) and antimicrobial potential against foodborne pathogenic bacteria. Through chemical assays, PPJs showed high contents of total polyphenols, flavonoids and betalains and marked antioxidant capacity. PPJs from the first harvest ("Agostani") revealed the significantly highest amount of polyphenols in white cultivar and of betacyanin and betaxanthin in yellow and red cultivars; antioxidant capacity was significantly higher in "Agostani" PPJs than in "Bastardoni" ones. Regarding antimicrobial potential, all PPJs revealed good antibacterial activity, particularly against Salmonella enterica as evidenced by the widest inhibition haloes. These results encourage the suitability of the first flowering prickly pear fruits, with low market value as fresh fruit but with high nutritional features, to be processed as semi-finished product. In particular, its use as ingredient in foods with high risk of Salmonella contamination may act as a natural preservative.

Grown to be Blue-Antioxidant Properties and Health Effects of Colored Vegetables. Part I: Root Vegetables

During the last few decades, the food and beverage industry faced increasing demand for the design of new functional food products free of synthetic compounds and artificial additives. Anthocyanins are widely used as natural colorants in various food products to replenish blue color losses during processing and to add blue color to colorless products, while other compounds such as carotenoids and betalains are considered as good sources of other shades. Root vegetables are well known for their broad palette of colors, and some species, such as black carrot and beet root, are already widely used as sources of natural colorants in the food and drug industry. Ongoing research aims at identifying alternative vegetable sources with diverse functional and structural features imparting beneficial effects onto human health. The current review provides a systematic description of colored root vegetables based on their belowground edible parts, and it highlights species and/or cultivars that present atypical colors, especially those containing pigment compounds responsible for hues of blue color. Finally, the main health effects and antioxidant properties associated with the presence of coloring compounds are presented, as well as the effects that processing treatments may have on chemical composition and coloring compounds in particular.

Protective Effects of Betanin against Oxidative Stress in a Peripheral Artery Vasospasm Model in Rat

Objective: The aim of this study is to determine protective/modulatory effects of betanin in a femoral artery vasospasm model in rats. Materials and Methods: Sprague-Dawley rats were divided into three groups. Group 1: sham (n = 7), group 2: vasospasm model only (n = 7), group 3: postoperative betanin treatment in the vasospasm model (n = 7). 100 mg/kg betanin was administered orally to group 3 for 7 days, postoperatively. Peripheral blood malondialdehyde (MDA) and nitric oxide (NO) levels were measured for the quantification of oxidative stress, lumen diameter and wall thickness of femoral artery segments were determined to assess vasodilator effects of betanin. Results: Femoral artery vasospasm formation significantly increased both MDA (13.54 ± 3.09 mmol/mL) and NO levels (0.61 ± 0.06 µmol/mL) relative to the sham (9.07 ± 1.09 and 0.48 ± 0.1, respectively). Upon betanin administration, both MDA and NO approached baseline levels (9.95 ± 0.92 and 0.5 ± 0.06, respectively). Pathological examination of lumen diameter and wall thickness of the femoral arteries also revealed that betanin administration resulted in significant increase in lumen diameter when compared to vasospasm group (614.15 ± 245.77 versus 117.40 ± 46.19 µm) and decrease in wall thickness (64.68 ± 14.13 versus 96.73 ± 9.20 µm). Conclusion: Betanin was shown to have protective effect against oxidative stress in a peripheral artery vasospasm model in rats. It may also have a role in mitigating maladaptive changes in arterial structure, as shown in pathological examination.

A Review of the Science of Colorful, Plant-Based Food and Practical Strategies for "Eating the Rainbow"

Over the past decades, thousands of published studies have amassed supporting recommendations to consume fruits and vegetables for physiological and psychological health. Newer research has emerged to suggest that these plant-based foods contain a plethora of not only vitamins and minerals, but perhaps, most importantly, phytonutrients. These phytonutrients have known pleiotropic effects on cellular structure and function, ultimately resulting in the modulation of protein kinases and subsequent epigenetic modification in a manner that leads to improved outcomes. Even though eating fruits and vegetables is a well-known feature of a healthy dietary pattern, population intakes continue to be below federal recommendations. To encourage consumers to include fruits and vegetables into their diet, an “eat by color” approach is proposed in this review. Although each individual food may have numerous effects based on its constituents, the goal of this simplified approach was to identify general patterns of benefits based on the preponderance of scientific data and known mechanisms of food-based constituents. It is suggested that such a consumer-oriented categorization of these plant-based foods may lead to greater recognition of their importance in the daily diet throughout the lifespan. Other adjunctive strategies to heighten awareness of fruits and vegetables are discussed.

Red Beetroot and Betalains as Cancer Chemopreventative Agents

Carcinogenesis is the process whereby a normal cell is transformed into a neoplastic cell. This action involves several steps starting with initiation and followed by promotion and progression. Driving these stages are oxidative stress and inflammation, which in turn encompasses a myriad of aberrant gene expressions, both within the transforming cell population and the cells within the surrounding lesion. Chemoprevention of cancer with bioreactive foods or their extracted/purified components occurs via normalizing these inappropriate gene activities. Various foods/agents have been shown to affect different gene expressions. In this review, we discuss whereby the chemoprevention activities of the red beetroot itself may disrupt carcinogenesis and the activities of the water-soluble betalains extracted from the plant.

Indicaxanthin from Opuntia ficus indica (L. Mill) Inhibits Oxidized LDL-Mediated Human Endothelial Cell Dysfunction through Inhibition of NF-κB Activation

Oxidized low-density lipoproteins (oxLDL) play a pivotal role in the etiopathogenesis of atherosclerosis through the activation of inflammatory signaling events eventually leading to endothelial dysfunction and senescence. In the present work, we investigated the effects of indicaxanthin, a bioavailable, redox-modulating phytochemical from Opuntia ficus indica fruits, with anti-inflammatory activity, against oxLDL-induced endothelial dysfunction. Human umbilical vein cord cells (HUVEC) were stimulated with human oxLDL, and the effects of indicaxanthin were evaluated in a range between 5 and 20 μM, consistent with its plasma level after a fruit meal (7 μM). Pretreatment with indicaxanthin significantly and concentration-dependently inhibited oxLDL-induced cytotoxicity; ICAM-1, VCAM-1, and ELAM-1 increase; and ABC-A1 decrease of both protein and mRNA levels. From a mechanistic perspective, we also provided evidence that the protective effects of indicaxanthin were redox-dependent and related to the pigment efficacy to inhibit NF-κB transcriptional activity. In conclusion, here we demonstrate indicaxanthin as a novel, dietary phytochemical, able to exert significant protective vascular effects in vitro, at nutritionally relevant concentrations.