Betalains in Some Species of the Amaranthaceae Family: A Review

Enhancing betacyanin stability: Comparison of dragon fruit (Hylocereus polyrhizus) pulp and peel powders through encapsulation technology during storage

Betacyanin can be found in the peel or pulp of dragon fruit. As a natural pigment, betacyanin is unstable, so it requires encapsulation technology to maintain its quality. The stability of encapsulated betacyanin from dragon fruit peel compared to dragon fruit pulp has yet to be discovered. This study aims to compare the stability of encapsulated betacyanin (with maltodextrin and gum Arabic) from dragon fruit peel and pulp dried with vacuum drying. Dragon fruit peel extraction utilized a 50% aqueous ethanol solvent, while pulp juice extraction was performed. The ratio of dragon fruit extract to coating materials was set at 1:3 (solid/solid). Research shows that dragon fruit juice powder had higher stability and phytochemical concentrations than the ethanol extract of dragon fruit peel powder during 30 days of storage. Despite similar color stability (similar range value of ΔE), the color from dragon fruit juice powder more closely resembled the natural fruit, albeit with weaker antioxidant activity than the peel powder. Betacyanin concentration in juice powder was notably higher (82.56-156.82 μg/g) than in the ethanol extract of dragon fruit peel powder (52.51-75.12 μg/g). A combination of maltodextrin and Arabic gum (1:1) as coating materials demonstrated the highest concentrations of total phenolic and total betacyanin (81.15-95.87 mg/g and 121.91-156.82 μg/g, respectively) during the storage period. These findings contribute to our comprehension of betacyanin stability and functionality, facilitating precise applications in industrial processing environments based on their source attributes.

The amount of antioxidants in honey has a strong relationship with the plants selected by honey bees

As one of the main sources of natural antioxidants, flowering plants play a role in the prevention and treatment of many diseases directly and indirectly. Honey is considered as an important nutrient in the supply of natural antioxidants, the amount of which is directly dependent on the plant origin and geographical location of the bee feeding place. The existence of valuable communities of native and endemic plant species has turned Alborz, Zagros and Azerbaijan into the most important hubs of honey production in Iran. In this study, we collected samples of honey from more than 90 regions in Alborz, Zagros and Azerbaijan during the years 2020 to 2021. We evaluated the samples using melissopalynology method and measuring the amount of antioxidant activity. The rise of antioxidant activity in honey is dependent on the abundance of some plant families as well botanical origins. The abundance of plant families Rosaceae, Amaranthaceae, Fabaceae and Asteraceae showed a higher influence on the amount of antioxidants in honey than other plant families. Also, the abundance of plant families Rosaceae and Fabaceae increased with increasing altitude. In general, the amount of antioxidant activity of honey samples shows a different percentage under the influence of ecological and geographical changes.

Microencapsulation of Betaxanthin Pigments from Pitahaya (Hylocereus megalanthus) By-Products: Characterization, Food Application, Stability, and In Vitro Gastrointestinal Digestion

The yellow pitahaya peels generated as by-products during the consumption and processing of the fresh fruit are a rich and underutilized source of betaxanthins (natural yellow-orange pigment with antioxidant activity) and mucilage (structuring material used in the spray-drying process), molecules of high interest for the food industry. In this work, the betaxanthin-rich extract (BRE) obtained from this by-product was microencapsulated by spray drying (SD) using pitahaya peel mucilage (MPP) and maltodextrin (MD) as wall materials. Both types of microencapsulates (i.e., SD-MPP and SD-MD) retained high betaxanthin content (as measured by UV-vis) and antioxidant activity (ORAC). These microencapsulates were characterized structurally (FTIR and zeta potential), morphologically (SEM and particle size/polydispersity index), and thermally (DSC/TGA). The powdered microencapsulates were incorporated into the formulation of candy gummies as a food model, which were subjected to an in vitro gastrointestinal digestion process. The characterization study (FTIR and antioxidant activity) of the microcapsules showed that the fruit peel mucilage favors the retention of betaxanthins, while the SEM analysis revealed a particle size of multimodal distribution and heterogeneous morphology. The addition of SD-MPP microcapsules in the candy gummy formulation favored the total dietary fiber content as well as the gumminess and chewiness of the food matrix; however, the inhibition of AAPH^• (%) was affected. The stability of the yellow color in the gummies after 30 days of storage indicates its suitability for storage. Consequently, the microencapsulation of betaxanthins with pitahaya peel mucilage can be used as a food additive colorant in the food industry, replacing synthetic colorants, to develop products with beneficial qualities for health that can satisfy the growing demand of consumers.

Betalains as promising natural colorants in smart/active food packaging

Betalains are water-soluble nitrogen pigments with beneficial effects, including antioxidant, antimicrobial, and pH-indicator properties. The development of packaging films incorporated with betalains has received increasing attention because of pH-responsive color-changing properties in the colorimetric indicators and smart packaging films. As such, intelligent and active packaging systems based on biodegradable polymers containing betalains have been recently developed as eco-friendly packaging to enhance the quality and safety of food products. Betalains could generally improve the functional properties of packaging films, such as higher water resistance, tensile strength, elongation at break, and antioxidant and antimicrobial activities. These effects are dependent on betalain composition (about its source and extraction), content, and the kind of biopolymer, film preparation method, food samples, and storage time. This review focused on betalains-rich films as pH- and ammonia-sensitive indicators and their applications as smart packaging to monitor the freshness of protein-rich foods such as shrimp, fish, chicken, and milk.

Recent advancements in natural colorants and their application as coloring in food and in intelligent food packaging

Colorants are widely employed in the food industry as an essential ingredient in many products since color is one of the most valued attributes by consumers. Furthermore, the utilization of colorants is currently being extended to the food packaging technologies. The objective of this review was to compile recent information about the main families of natural coloring compounds, and to describe their real implications in food coloring. In addition, their technological use in different food systems (namely, bakery products, beverages, meat and meat products, and dairy products) and their utilization in intelligent packaging to monitor the freshness of foodstuffs with the aim of extending food shelf life and improving food properties was discussed. The potential of using natural colorant in different food to improve their color has been demonstrated, although color stability is still a challenging task. More interestingly, the application of intelligent colorimetric indicators to exhibit color changes with variations in pH can enable real-time monitoring of food quality.

Pleiotropic Functions of Nitric Oxide Produced by Ascorbate for the Prevention and Mitigation of COVID-19: A Revaluation of Pauling's Vitamin C Therapy

Linus Pauling, who was awarded the Nobel Prize in Chemistry, suggested that a high dose of vitamin C (l-ascorbic acid) might work as a prevention or treatment for the common cold. Vitamin C therapy was tested in clinical trials, but clear evidence was not found at that time. Although Pauling's proposal has been strongly criticized for a long time, vitamin C therapy has continued to be tested as a treatment for a variety of diseases, including coronavirus infectious disease 2019 (COVID-19). The pathogen of COVID-19, SARS-CoV-2, belongs to the β-coronavirus lineage, which includes human coronavirus, severe acute respiratory syndrome (SARS), and Middle East respiratory syndrome (MERS). This review intends to shed new light on vitamin C antiviral activity that may prevent SARS-CoV-2 infection through the chemical production of nitric oxide (NO). NO is a gaseous free radical that is largely produced by the enzyme NO synthase (NOS) in cells. NO produced by upper epidermal cells contributes to the inactivation of viruses and bacteria contained in air or aerosols. In addition to enzymatic production, NO can be generated by the chemical reduction of inorganic nitrite (NO₂^-), an alternative mechanism for NO production in living organisms. Dietary vitamin C, largely contained in fruits and vegetables, can reduce the nitrite in saliva to produce NO in the oral cavity when chewing foods. In the stomach, salivary nitrite can also be reduced to NO by vitamin C secreted from the epidermal cells of the stomach. The strong acidic pH of gastric juice facilitates the chemical reduction of salivary nitrite to produce NO. Vitamin C contributes in multiple ways to the host innate immune system as a first-line defense mechanism against pathogens. Highlighting chemical NO production by vitamin C, we suggest that controversies on the therapeutic effects of vitamin C in previous clinical trials may partly be due to less appreciation of the pleiotropic functions of vitamin C as a universal bioreductant.

Dissociation Mode of the O-H Bond in Betanidin, pKa-Clusterization Prediction, and Molecular Interactions via Shape Theory and DFT Methods

Betanidin (Bd) is a nitrogenous metabolite with significant bioactive potential influenced by pH. Its free radical scavenging activity and deprotonation pathway are crucial to studying its physicochemical properties. Motivated by the published discrepancies about the best deprotonation routes in Bd, this work explores all possible pathways for proton extractions on that molecule, by using the direct approach method based on pK_a. The complete space of exploration is supported by a linear relation with constant slope, where the pK_a is written in terms of the associated deprotonated molecule energy. The deprotonation rounds 1, …, 6 define groups of parallel linear models with constant slope. The intercepts of the models just depend on the protonated energy for each round, and then the pK_a can be trivially ordered and explained by the energy. We use the direct approximation method to obtain the value of pK_a. We predict all possible outcomes based on a linear model of the energy and some related verified assumptions. We also include a new measure of similarity or dissimilarity between the protonated and deprotonated molecules, via a geometric-chemical descriptor called the Riemann-Mulliken distance (RMD). The RMD considers the cartesian coordinates of the atoms, the atomic mass, and the Mulliken charges. After exploring the complete set of permutations, we show that the successive deprotonation process does not inherit the local energy minimum and that the commutativity of the paths does not hold either. The resulting clusterization of pK_a can be explained by the local acid and basic groups of the BD, and the successive deprotonation can be predicted by using the chemical explained linear models, which can avoid unnecessary optimizations. Another part of the research uses our own algorithm based on shape theory to determine the protein's active site automatically, and molecular dynamics confirmed the results of the molecular docking of Bd in protonated and anionic form with the enzyme aldose reductase (AR). Also, we calculate the descriptors associated with the SET and SPLET mechanisms.

Antioxidant and Antimicrobial Effects of Baby Leaves of Amaranthus tricolor L. Harvested as Vegetable in Correlation with Their Phytochemical Composition

Amaranth is used as a spinach replacement; therefore, it is sometimes called Chinese Spinach. So far, the activity of the plant has not been associated with the presence of specific compounds. Three cultivars of Amaranthus tricolor L. were investigated for their antioxidant and antimicrobial activities. The correlation between the bioactivity and metabolite profiles was investigated in order to indicate active compounds in A. tricolor. The phytochemical profile of a total of nine extracts was studied by HPLC-DAD-ESI/HRMS, revealing the presence of 52 compounds. The highest antioxidant activity was noticed in the Red cultivar (0.06 mmol TE/g DE (Trolox Equivalent/Dry Extract Weight) and was related to the presence of amino acids, flavonoids and phenolic acids, as well as individual compounds such as tuberonic acid hexoside. All studied extracts revealed antimicrobial activity. Gram-positive bacteria were more susceptible to N-(carboxyacetyl) phenylalanine, phenylalanine, tuberonic acid and succinic acid and Gram-negative bacteria to dopa, tryptophan, norleucine, tuberonic acid hexoside, quercetin-O-hexoside, luteolin-O-rhamnosylhexoside, luteolin-6-C-hexoside succinic acid, gallic acid-O-hexoside, dihydroxybenzoic acid and hydroxybenzoic acid. Maleic acid showed promising antifungal activity. In summary, A. tricolor is a good source of antioxidant and antimicrobial compounds.

Molecular and Antioxidant Characterization of Opuntia robusta Fruit Extract and Its Protective Effect against Diclofenac-Induced Acute Liver Injury in an In Vivo Rat Model

A molecular characterization of the main phytochemicals and antioxidant activity of Opuntia robusta (OR) fruit extract was carried out, as well as an evaluation of its hepatoprotective effect against diclofenac (DF)-induced acute liver injury was evaluated. Phenols, flavonoids and betalains were quantified, and antioxidant characterization was performed by means of the ABTS^•+, DPPH and FRAP assays. UPLC-QTOF-MS/MS was used to identify the main biocompounds present in OR fruit extract was carried out via. In the in vivo model, groups of rats were treated prophylactically with the OR fruit extract, betanin and N-acteylcysteine followed by a single dose of DF. Biochemical markers of oxidative stress (MDA and GSH) and relative gene expression of the inducible antioxidant response (Nrf2, Sod2, Hmox1, Nqo1 and Gclc), cell death (Casp3) and DNA repair (Gadd45a) were analyzed. Western blot analysis was performed to measure protein levels of Nrf2 and immunohistochemical analysis was used to assess caspase-3 activity in the experimental groups. In our study, the OR fruit extract showed strong antioxidant and cytoprotective capacity due to the presence of bioactive compounds, such as betalain and phenols. We conclude that OR fruit extract or selected components can be used clinically to support patients with acute liver injury.

Salt Eustress Induction in Red Amaranth (Amaranthus gangeticus) Augments Nutritional, Phenolic Acids and Antiradical Potential of Leaves

Earlier researchers have highlighted the utilization of salt eustress for boosting the nutritional and phenolic acid (PA) profiles and antiradical potential (ARP) of vegetables, which eventually boost food values for nourishing human diets. Amaranth is a rapidly grown, diversely acclimated C4 leafy vegetable with climate resilience and salinity resistance. The application of salinity eustress in amaranth has a great scope to augment the nutritional and PA profiles and ARP. Therefore, the A. gangeticus genotype was evaluated in response to salt eustress for nutrients, PA profile, and ARP. Antioxidant potential and high-yielding genotype (LS1) were grown under four salt eustresses (control, 25 mM, 50 mM, 100 mM NaCl) in a randomized completely block design (RCBD) in four replicates. Salt stress remarkably augmented microelements, proximate, macro-elements, phytochemicals, PA profiles, and ARP of A. gangeticus leaves in this order: control < low sodium chloride stress (LSCS) < moderate sodium chloride stress (MSCS) < severe sodium chloride stress (SSCS). A large quantity of 16 PAs, including seven cinnamic acids (CAs) and nine benzoic acids (BAs) were detected in A. gangeticus genotypes. All the microelements, proximate, macro-elements, phytochemicals, PA profiles, and ARP of A. gangeticus under MSCS, and SSCS levels were much higher in comparison with the control. It can be utilized as preferential food for our daily diets as these antiradical compounds have strong antioxidants. Salt-treated A. gangeticus contributed to excellent quality in the end product in terms of microelements, proximate, macro-elements, phytochemicals, PA profiles, and ARP. A. gangeticus can be cultivated as an encouraging substitute crop in salt-affected areas of the world.

Antimicrobial betalains

Betalains are nitrogen-containing plant pigments that can be red-violet (betacyanins) or yellow-orange (betaxanthins), currently employed as natural colourants in the food and cosmetic sectors. Betalains exhibit antimicrobial activity against a broad spectrum of microbes including multidrug-resistant bacteria, as well as single-species and dual-species biofilm-producing bacteria, which is highly significant given the current antimicrobial resistance issue reported by The World Health Organization. Research demonstrating antiviral activity against dengue virus, in silico studies including SARS-CoV-2, and anti-fungal effects of betalains highlight the diversity of their antimicrobial properties. Though limited in vivo studies have been conducted, antimalarial and anti-infective activities of betacyanin have been observed in living infection models. Cellular mechanisms of antimicrobial activity of betalains are yet unknown; however existing research has laid the framework for a potentially novel antimicrobial agent. This review covers an overview of betalains as antimicrobial agents and discussions to fully exploit their potential as therapeutic agents to treat infectious diseases.

Starter culture-related changes in free amino acids, biogenic amines profile, and antioxidant properties of fermented red beetroot grown in Poland

Fermentation of two red beet cultivars (Wodan and Alto) with single-strain starter cultures consisting of selected strains of lactic acid bacteria (LAB) of plant origin (Weissella cibaria KKP2058, Levilactobacillus brevis ZF165) and a multi-strain culture (containing W. cibaria KKP2058, L. brevis ZF165, Lactiplantibacillus plantarum KKP1822, Limosilactobacillus fermentum KKP1820, and Leuconostoc mesenteroides JEIIF) was performed to evaluate their impact on betalains, free amino acids, formation of biogenic amines, and antioxidative properties of the juice formed. Next-generation sequencing data analysis used to identify the microbial community revealed that the starter cultures promoted the dominance of the genus Lactobacillus, and decreased the proportion of spoilage bacteria compared to spontaneously fermented juices. Generally, the fermentation process significantly influenced the amount of the analyzed compounds, leading in most cases to their reduction. The observed changes in the studied parameters depended on the starter culture used, indicating different metabolic activities of the LAB strains towards bioactive compounds. The use of multi-strain starter cultures allowed to largely prevent the reduction of betacyanins and histamine formation.

Alternanthera sessilis: Uncovering the nutritional and medicinal values of an edible weed

ETHNOPHARMACOLOGICAL RELEVANCE

Weeds are often considered undesirable as they interfere with the habitat of native plants, and therefore they are underestimated and underutilised. In fact, some edible weeds have beneficial nutritional and medicinal values. Alternanthera sessilis (L.) R. Br. ex DC., an edible medicinal weed is a species of the Amaranthaceae family that consists of two cultivars: green and red. Local communities in different regions have traditionally consumed the plants as food and medicine, with the green cultivar being applied to relieve pain, treat wound healing, dysentery, asthma and hypertension, while the red cultivar is applied to prevent cardiovascular and liver diseases in general.

AIM OF THE STUDY

The present review intends to provide an in-depth discussion and scientific basis of A. sessilis green and red's health-promoting properties in relation to their ethnobotanical use, nutritional components and bioactive compounds.

MATERIALS AND METHODS

The literature search was conducted using relevant keywords on scientific search engines such as the Web of Science, Google Scholar, Medline and Scopus.

RESULTS

A. sessilis shows potent antioxidant activity as a result of its diverse phytochemical constituents, such as polyphenols, terpenes, alkaloid and carotenoids in addition to its nutritional components: vitamin C, E and unsaturated fatty acids, which contribute to its various bioactive properties: anti-microbial and anthelmintic, anti-diabetic, lipid lowering, anti-inflammatory and analgesic activities, anti-cancer and other biological activities. Toxicity evaluation revealed the absence of adverse effect of A. sesslis extracts.

CONCLUSION

A. sessilis has a great potential to be used as complementary medicine and ingredients for pharmaceuticals, nutraceuticals and functional foods, instead of being regarded as a pest. Prospects for enhancing the development and commercialisation of this edible medicinal weed as a high value health-promoting product are suggested.

Betalains: colours for human health

In the last years, the use of natural phytochemical compounds as protective agents in the prevention and treatment of obesity and the related-metabolic syndrome has gained much attention worldwide. Different studies have shown health benefits for many vegetables such Opuntia ficus-indica and Beta vulgaris and their pigments collectively referred as betalains. Betalains exert antioxidative, anti-inflammation, lipid lowering, antidiabetic and anti-obesity effects. This review summarizes findings in the literature and highlights the therapeutic potential of betalains and their natural source as valid alternative for supplementation in obesity-related disorders treatment. Further research is needed to establish the mechanisms through which these natural pigments exert their beneficial effects and to translate the promising findings from animal models to humans.

Colorant Pigments, Nutrients, Bioactive Components, and Antiradical Potential of Danta Leaves (Amaranthus lividus)

In the Indian subcontinent, danta (stems) of underutilized amaranth are used as vegetables in different culinary dishes. At the edible stage of the danta, leaves are discarded as waste in the dustbin because they are overaged. For the first time, we assessed the colorant pigments, bioactive components, nutrients, and antiradical potential (AP) of the leaves of danta to valorize the by-product (leaf) for antioxidant, nutritional, and pharmacological uses. Leaves of danta were analyzed for proximate and element compositions, colorant pigments, bioactive constituents, AP (DPPH), and AP (ABTS⁺). Danta leaves had satisfactory moisture, protein, carbohydrates, and dietary fiber. The chosen danta leaves contained satisfactory magnesium, iron, calcium, potassium, manganese, copper, and zinc; adequate bioactive pigments, such as betacyanins, carotenoids, betalains, β-carotene, chlorophylls, and betaxanthins; and copious bioactive ascorbic acid, polyphenols, flavonoids, and AP. The correlation coefficient indicated that bioactive phytochemicals and colorant pigments of the selected danta leaves had good AP as assessed via ABTS⁺ and DPPH assays. The selected danta leaves had good ROS-scavenging potential that could indicate massive possibilities for promoting the health of the nutraceutical- and antioxidant-deficit public. The findings showed that danta leaves are a beautiful by-product for contributing as an alternate origin of antioxidants, nutrients, and bioactive compounds with pharmacological use.

The Impact of the Fermentation Method on the Pigment Content in Pickled Beetroot and Red Bell Pepper Juices and Freeze-Dried Powders

The beetroot and red bell pepper are vegetables rich in active ingredients, and their potential for health benefits are crucial. Both presented raw materials are rich in natural pigments, but are unstable and seasonal; thus, it was decided to take steps to extend their durability. Lactic fermentation has been recognized as a food preservation method, requiring minimal resources. The activities undertaken were also aimed at creating a new product with a coloring and probiotic potential. For this reason, the study aimed to evaluate the impact of the method of fermentation on the content of active compounds (pigments) in pickled juices and freeze-dried powders. The lactic acid fermentation guided in two ways. The second step of the research was to obtain powders in the freeze-drying process. For fermentation, Levilactobacillus brevis and Limosilactobacillus fermentum were used. In juices and powders, pigments, color, and dry matter were tested. In this research, no differences in fermented juice pigment contents were seen; however, the color coefficient differed in raw juices. The freeze-drying process resulted in lowering the pigment content, and increasing dry matter and good storage conditions (glass transition temperatures 48–66 °C). The selection of vegetable methods suggested the use of fermentation and mixing it with a marinade (higher pigments and lactic acid bacteria content). All powders were stable and can be used as a colorant source, whereas for probiotic properties, a higher number of bacteria is needed.

Phytonutrients, Colorant Pigments, Phytochemicals, and Antioxidant Potential of Orphan Leafy Amaranthus Species

The underutilized Amaranthus leafy vegetables are a unique basis of pigments such as β-cyanins, β-xanthins, and betalains with radical scavenging capacity (RSC). They have abundant phytonutrients and antioxidant components, such as pigments, vitamins, phenolics, and flavonoids. Eight selected genotypes (four genotypes from each species) of underutilized Amaranthus leafy vegetables were evaluated for phytonutrients, pigments, vitamins, phenolics, flavonoids, and antioxidants in a randomized complete block design under ambient field conditions with three replicates. The studied traits showed a wide range of variations across eight genotypes of two species of Amaranthus leafy vegetables. The highest fat, β-xanthins, K, dietary fiber, Mg, β-cyanins, Mn, chlorophyll ab, Zn, TP, TF, betalains, chlorophyll a content, and (RSC) (DPPH) and RSC (ABTS+) were obtained from A. tricolor accessions. Conversely, the highest protein, Cu, carbohydrates, Ca, and chlorophyll b content were obtained from A. lividus accessions. The highest dry matter, carotenoids, Fe, energy, and ash were obtained from A. tricolor and A. lividus. The accession AT2 confirmed the highest vit. C and RSC (DPPH) and RSC (ABTS+); AT5 had the highest TP content; and AT12 had the highest TF content. A. tricolor accessions had high phytochemicals across the two species, such as phytopigments, vitamins, phenolics, antioxidants, and flavonoids, with considerable nutrients and protein. Hence, A. tricolor accessions can be used as high-yielding cultivars comprising ample antioxidants. The correlation study revealed that vitamin C, pigments, flavonoids, β-carotene, and phenolics demonstrated a strong RSC, and showed a substantial contribution to the antioxidant potential (AP) of A. tricolor. The investigation exposed that the accessions displayed a plentiful origin of nutritional values, phytochemicals, and AP with good quenching ability of reactive oxygen species (ROS) that provide enormous prospects for nourishing the mineral-, antioxidant-, and vitamin-threatened community.

Current Trends in Computational Quantum Chemistry Studies on Antioxidant Radical Scavenging Activity

The antioxidative nature of chemicals is now routinely studied using computational quantum chemistry. Scientists are constantly proposing new approaches to investigate those methods, and the subject is evolving at a rapid pace. The goal of this review is to collect, consolidate, and present current trends in a clear, methodical, and reference-rich manner. This paper is divided into several sections, each of which corresponds to a different stage of elaborations: preliminary concerns, electronic structure analysis, and general reactivity (thermochemistry and kinetics). The sections are further subdivided based on methodologies used. Concluding remarks and future perspectives are presented based on the remaining elements.

Red pitaya (Hylocereus costaricensis) peel as a source of valuable molecules: Extraction optimization to recover natural colouring agents

Hylocereus costaricensis peel contains large amounts of betacyanins and can be exploited as a source of natural colorants. This work aimed the chemical characterization and evaluation of bioactive properties of this by-product and the optimization of the ultrasound-assisted extraction (UAE) of betacyanins using the response surface methodology (RSM). Oxalic and malic acids and traces of fumaric acid were detected, as well as the four tocopherol isoforms, predominantly γ-tocopherol. Four betacyanins were identified and used as response criteria for UAE optimization, namely phyllocactin, isobetanin, isophyllocactin, and betanin. Sample processing at 487 W for 38 min result in the maximum betacyanin content (36 ± 1 mg/g dw). The peel extract inhibit the oxidative haemolysis, with IC₅₀ values of 255 and 381 μg/mL for Δt of 60 and 120 min, respectively, and the growth of pathogenic bacteria, with minimum inhibitory concentrations ranging from 5 to 20 mg/mL. Furthermore, no toxicity was observed for normal cells.

Influence of Fermentation Beetroot Juice Process on the Physico-Chemical Properties of Spray Dried Powder

Picking vegetables is, along with salting and drying, one of the oldest ways to preserve food in the world. This is the process of decomposition of simple sugars into lactic acid with the participation of lactic bacteria. The aim of the study was to obtain powders from fermented red beet juice with the highest possible amount of lactic acid bacteria (LAB) and active ingredients. For the analysis, juices were squeezed from the vegetables and two types of fermentation were used: a spontaneous fermentation and a dedicated one. After inoculation, samples were taken for analysis on a daily basis. Extract, pH, total acidity, pigments, and color were measured. In addition, microbiological tests were also carried out. The juices from the fifth day of fermentation was also spray dried, to obtain fermented beetroot powder. Juices from 3–5th day were characterized by a high content of LAB and betanin, had also a low pH, which proves that the lactic fermentation is working properly. The exception was the juice from spontaneous fermentation. According to the observations, the fermentation process did not run properly, and further analysis is needed. The powders were stable; however, results obtained from the pigment content and the LAB content are not satisfactory and require further analysis.

Expression of apple MdMYB10 transcription factor in sugar beet with a screenable marker role and antimicrobial activity

Selection of transgenic plants by using genes encoding screenable markers of plant origin with health benefit properties, such as anthocyanin is an important aim in plant genetic engineering. In this study, Malus domestica MYB10 (MdMYB10) gene, was used for Agrobacterium tumefaciens-mediated transformation of two SBS-02 and SBS-04 sugar beet lines. The impact of different light regimes on plant tissue culture from a combination of light, dark/light and dark was investigated. The results of this study showed that the MdMYB10 gene was successfully integrated into the selected purple transgenic lines, suggesting that the expression of MdMYB10 gene in sugar beet shoots can be used as a screenable markers for transformation, possibly replacing antibiotic resistant genes. Furthermore, the results of the antibacterial activity of transgenic plants extracts showed that the total extract obtained from transgenic lines significantly (P < 0.01) inhibited the growth and development of Enterococcus faecium and Enterococcus faecalis bacteria compared to the non-transgenic plants. The results of this study showed that the combination of betalain with vancomycin demonstrated a synergistic antimicrobial effect, also, suggesting that the expression of MdMYB10 may play a dual role by accumulating betalain and exhibiting a screenable markers function.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13205-022-03120-7.

Bioactives and extracts affect the physico-chemical properties of concentrated whey protein isolate dispersions

Non-covalent complexation interactions are known to occur between bioactive compounds and proteins. While formulating with these components can have positive outcomes such as stabilization of colors and actives, it can also result in changes to the structures and physical properties of proteins, affecting product functionality and sensory attributes. Previous experiments reported measurable changes in the physico-chemical properties of whey protein isolate (WPI) dispersions upon formulation with Aronia berry extract, ascribing changes to protein-polyphenol (PP) interactions in the systems. Pure gallotannin, beet extract, and cranberry extract, providing a diverse variety structures and sizes, were selected for further experimentation and comparison with the effects of Aronia extract. Concentrated dispersions with varying WPI:sucrose ratios, formulated with several bioactives contents from multiple different sources were analyzed to identify the effects of different bioactives on physico-chemical properties of dispersions. Dispersions formulated with cranberry extract demonstrated the largest increases in surface tensions, viscosities, and particle sizes, while those formulated with beet extract were the least affected by the presence of bioactives, suggesting that different bioactives and extracts had varying propensities for complexation interactions with WPI, despite their relatively low levels of addition (0, 0.5, and 1%).

Graphical Abstract

Comprehensive Betalain Profiling of Djulis (Chenopodium formosanum) Cultivars Using HPLC-Q-Orbitrap High-Resolution Mass Spectrometry

Betalains are water-soluble pigments that may be used as alternatives to artificial colorants in the food industry. In addition, the betalain profile may be of taxonomic significance to some higher plants. Djulis (Chenopodium formosanum) is an emerging crop grown by Taiwan aboriginal communities, and its various cultivars contain different betalain compositions. To develop an authenticity method for evaluating djulis cultivars, we performed comprehensive betalain profiling with HPLC-Q-Orbitrap high-resolution mass spectrometry (HRMS). An HRMS method for betalain annotation was developed and used to identify 68 betalains, including 10 betacyanins, 24 betacyanin derivatives, and 34 betaxanthins. The profile of betacyanins and their derivatives could be utilized to classify different cultivars of djulis, while betaxanthins were less informative. Furthermore, the betalain profiles were indicative of the geographic origin of djulis. This HRMS method and analytical platform for betalains may be helpful to guide further investigations of natural pigments in other plants.

Preparation, characterization and application of smart packaging films based on locust bean gum/polyvinyl alcohol blend and betacyanins from cockscomb (Celosia cristata L.) flower

Cockscomb (Celosia cristata L.) is an edible and ornamental plant rich in natural pigments of betacyanins. In this study, smart packaging films were developed based on locust bean gum (LBG), polyvinyl alcohol (PVA) and betacyanins from cockscomb flower. Effect of cockscomb flower extract content (4 wt%, 8 wt% and 12 wt%) on the structural, physical and functional properties of LBG/PVA blend films was investigated. The addition of cockscomb flower extract elevated the immiscibility between LBG and PVA. Cockscomb flower extract interacted with LBG and PVA through hydrogen bonds, resulting in reduced film crystallinity. The film containing 8 wt% of cockscomb flower extract showed the lowest water vapor permeability (10.34 × 10^-11 g m^-1 s^-1 Pa^-1) and the highest tensile strength (23.63 MPa). The film containing 12 wt% cockscomb flower extract exhibited the lowest light transmittance and the highest elongation at break (41.12%) and antioxidant activity. Cockscomb flower extract made the films become reddish-purple and endowed the films with pH-sensitivity and ammonia-sensitivity. The films containing cockscomb flower extract showed obvious color changes from reddish-purple to brown/yellow when shrimp spoiled. Our results suggested LBG/PVA blend films with cockscomb flower extract were suitable smart packaging films for indicating shrimp freshness.

The Compositional Aspects of Edible Flowers as an Emerging Horticultural Product

Edible flowers are becoming very popular, as consumers are seeking healthier and more attractive food products that can improve their diet aesthetics and diversify their dietary sources of micronutrients. The great variety of flowers that can be eaten is also associated with high variability in chemical composition, especially in bioactive compounds content that may significantly contribute to human health. The advanced analytical techniques allowed us to reveal the chemical composition of edible flowers and identify new compounds and effects that were not known until recently. Considering the numerous species of edible flowers, the present review aims to categorize the various species depending on their chemical composition and also to present the main groups of compounds that are usually present in the species that are most commonly used for culinary purposes. Moreover, special attention is given to those species that contain potentially toxic or poisonous compounds as their integration in human diets should be carefully considered. In conclusion, the present review provides useful information regarding the chemical composition and the main groups of chemical compounds that are present in the flowers of the most common species.

Evaluation of Bioactive Metabolites and Antioxidant-Rich Extracts of Amaranths with Possible Role in Pancreatic Lipase Interaction: In Silico and In Vitro Studies

Fat/carbohydrate-rich diet consumption or elevated secretion of pancreatic lipase (PL) in pancreatic injury results in increased fat digestion and storage. Several metabolites in plant-based diets can help achieve the requirements of nutrition and fitness together. Presently, nutritional metabolites from Amaranthus tricolor, A. viridis, and Achyranthes aspera were assessed and predicted for daily intake. The volatile-metabolite profiling of their extracts using GC-MS revealed various antioxidant and bioactive components. The implication of these specialized components and antioxidant-rich extracts (EC₅₀ free radical scavenging: 34.1 ± 1.5 to 166.3 ± 14.2 µg/mL; FRAP values: 12.1 ± 1.0 to 34.0 ± 2.0 µg Trolox Equivalent/mg) in lipolysis regulation by means of interaction with PL was checked by in silico docking (Betahistine and vitamins: ΔGbind -2.3 to -4.4 kcal/mol) and in vitro fluorescence quenching. Out of the various compounds and extracts tested, Betahistine, ATRA and AVLA showed better quenching the PL fluorescence. The identification of potential extracts as source of functional components contributing to nutrition and fat regulation can be improved through such study.

Plant-Derived Colorants for Food, Cosmetic and Textile Industries: A Review

This review provides a report on properties and recent research advances in the application of plant-derived colorants in food, cosmetics and textile materials. The following colorants are reviewed: Polyphenols (anthocyanins, flavonol-quercetin and curcumin), isoprenoids (iridoids, carotenoids and quinones), N-heterocyclic compounds (betalains and indigoids), melanins and tetrapyrroles with potential application in industry. Future aspects regarding applications of plant-derived colorants in the coloration of various materials are also discussed.

Antiradical Activity of Beetroot (Beta vulgaris L.) Betalains

Flavonoids, phenolic acids, and anthocyanidins are widely studied polyphenolics owing to their antiradical activity. Recently, beetroot dyes have drawn an attention as possible radical scavengers, but scant information can be found on this topic. In this study selected compounds were investigated using computational chemistry methods. Implicit water at physiological pH was chosen as the environment of interest. Betalains' dissociation process and electronic structure were examined, as well as the reactivity in six pathways against some common radicals, such as hydroxyl, hydroperoxide, superoxide, and nitric oxide. The study showed that all carboxyl groups are dissociated in the given conditions. The dissociation process impacts the electronic structure, which has consequences for the overall activity. Highly stabilized conjugated structures favor the electron-accepting type of scavenging reactions, primarily by a radical adduct formation mechanism. Betanidin and indicaxanthin were found to be the most promising of the compounds studied. Nevertheless, the study established the role of betalains as powerful antiradical dietary agents.

Chemical and Bioactive Features of Amaranthus caudatus L. Flowers and Optimized Ultrasound-Assisted Extraction of Betalains

The vibrant colours of many plants are due to secondary metabolites, such as nitrogen-containing compounds, where betacyanins are included. These compounds can be found in plants such as Amaranthus caudatus L. that, due to their high nutritional benefits, have been overproduced, which leads to the accumulation of large amounts of bio-residues. Among these bio-residues, the flowers which have a very intense pink colour and present no economic value or subsequent destination can be exploited as sources of natural colouring agents (betacyanins). This work aimed at characterising the flower’s extract in terms of bioactive molecules such as tocopherols, organic acids, but essentially in terms of betacyanins, in order to obtain a natural colouring agent. For the extraction, ultrasound-assisted extraction (UAE) ideal conditions were obtained using the Response Surface Methodology (RSM), allowing the attainment of an enriched extract of betacyanins in high yields and purity. The obtained extracts were analysed for their bioactive potential, namely antioxidant, antimicrobial and cytotoxic properties. From the obtained results, three isoforms of tocopherols were detected, β-tocopherol (0.884 ± 0.003 mg/100 g dry weight (dw)) being the most abundant one. Regarding the organic acids, oxalic (2.48 ± 0.05 mg/100 g dw), shikimic (0.170 ± 0.003 mg/100 g dw) and traces of fumaric acid were found. Four betacyanins were identified and quantified, namely: amaranthine (171 ± 1 mg/g extract), isoamaranthine (38 ± 1 mg/g extract), betanin (1.6 ± 0.1 mg/g), and isobetanin (1.3 ± 0.1 mg/g extract). The obtained extract also presented antioxidant activity with inhibition concentration (IC₅₀ values) of 29.0 ± 0.4 μg/mL and 114 ± 4 μg/mL for Δt of 60 min and 120 min, respectively in the oxidative haemolysis inhibition assay (OxHLIA) assay. The obtained extract also presented an interesting antibacterial activity with minimum inhibitory concentrations ranging from 5 to 20 mg/mL against pathogenic bacteria and revealed no toxicity for normal cells.

Elucidation of the core betalain biosynthesis pathway in Amaranthus tricolor

Amaranthus tricolor L., a vegetable Amaranthus species, is an economically important crop containing large amounts of betalains. Betalains are natural antioxidants and can be classified into betacyanins and betaxanthins, with red and yellow colors, respectively. A. tricolor cultivars with varying betalain contents, leading to striking red to green coloration, have been commercially produced. However, the molecular differences underlying betalain biosynthesis in various cultivars of A. tricolor remain largely unknown. In this study, A. tricolor cultivars with different colors were chosen for comparative transcriptome analysis. The elevated expression of AmCYP76AD1 in a red-leaf cultivar of A. tricolor was proposed to play a key role in producing red betalain pigments. The functions of AmCYP76AD1, AmDODAα1, AmDODAα2, and AmcDOPA5GT were also characterized through the heterologous engineering of betalain pigments in Nicotiana benthamiana. Moreover, high and low L-DOPA 4,5-dioxygenase activities of AmDODAα1 and AmDODAα2, respectively, were confirmed through in vitro enzymatic assays. Thus, comparative transcriptome analysis combined with functional and enzymatic studies allowed the construction of a core betalain biosynthesis pathway of A. tricolor. These results not only provide novel insights into betalain biosynthesis and evolution in A. tricolor but also provide a basal framework for examining genes related to betalain biosynthesis among different species of Amaranthaceae.

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.

Synergistic protective effect of Beta vulgaris with meso-2,3-dimercaptosuccinic acid against lead-induced neurotoxicity in male rats

Lead (Pb) toxicity is one of the most prevalent causes of human neurotoxicity. The available chelator drugs used now have many adverse effects. So, in this study, the protective role of Beta vulgaris juice (BVJ) on rat neurotoxicity induced by Pb was evaluated and the results were compared with the results of dimercaptosuccinic acid (DMSA, as used drug). Additionally, the synergistic effect of BVJ and DMSA against Pb-induced neurotoxicity was assessed. The study focused on the determination of the antioxidant, anti-inflammatory, and neurological potential of BVJ (alone, and with DMSA) towards lead-induced neurotoxicity. Also, the characterization of BVJ was studied. The results showed that BVJ contains considerable quantities of polyphenols, triterpenoids, and betalains which play an important role as antioxidants and anti-inflammatory. BVJ exhibited a protective effect against neurotoxicity via the reduction of Pb levels in blood and brain. Moreover, BVJ decreased the oxidative stress, inflammation, and cell death induced by Pb. Also, BVJ regulated the activities of acetylcholine esterase and monoamine oxidase-A which changed by Pb toxicity. BVJ and DMSA combination displayed a synergistic antineurotoxic effect (combination index ˂ 1). These results were in harmony with brain histopathology. Conclusion: BVJ has a powerful efficacy in the protection from brain toxicity via diminishing Pb in the brain and blood circulation, resulting in the prevention of the oxidative and inflammatory stress. Treatment with BVJ in combination with DMSA revealed a synergistic effect in the reduction of neurotoxicity induced by Pb. Also, the antioxidant and anti-inflammatory effects of the BVJ lead to the improvement of DMSA therapy.

A Review of Recent Studies on the Antioxidant Activities of a Third-Millennium Food: Amaranthus spp

Amaranth (Amaranthus spp.) plant commonly refers to the sustainable food crop for the 21st century. The crop has witnessed significant attention in recent years due to its high nutritional value and agronomic advantages. It is a relatively well-balanced cosmopolitan food that is a protector against chronic diseases. Usually, the antioxidant activities of amaranth are held responsible for its defensive behavior. Antioxidant activity of plants, generally, is attributed to their phytochemical compounds. The current interest, however, lies in hydrolysates and bioactive peptides because of their numerous biological functions, including antioxidant effect. While the importance of bioactive peptides has been progressively recognized, an integrated review of recent studies on the antioxidant ability of amaranth species, especially their hydrolysates and peptides has not been generated. Hence, in this review, we summarize studies focused on the antioxidant capacity of amaranth renewal over the period 2015-2020. It starts with a background and overall image of the amaranth-related published reviews. The current research focusing on in vitro, in vivo, and chemical assays-based antioxidant activity of different amaranth species are addressed. Finally, the last segment includes the latest studies concerning free radical scavenging activity and metal chelation capacity of amaranth protein hydrolysates and bioactive peptides.

Betacyanins and Betaxanthins in Cultivated Varieties of Beta vulgaris L. Compared to Weed Beets

There are 11 different varieties of Beta vulgaris L. that are used in the food industry, including sugar beets, beetroots, Swiss chard, and fodder beets. The typical red coloration of their tissues is caused by the indole-derived glycosides known as betalains that were analyzed in hypocotyl extracts by UV/Vis spectrophotometry to determine the content of betacyanins (betanin) and of betaxanthins (vulgaxanthin I) as constituents of the total betalain content. Fields of beet crops use to be also infested by wild beets, hybrids related to B. vulgaris subsp. maritima or B. macrocarpa Guss., which significantly decrease the quality and quantity of sugar beet yield; additionally, these plants produce betalains at an early stage. All tested B. vulgaris varieties could be distinguished from weed beets according to betacyanins, betaxanthins or total betalain content. The highest values of betacyanins were found in beetroots ‘Monorubra’ (9.69 mg/100 mL) and ‘Libero’ (8.42 mg/100 mL). Other beet varieties contained less betacyanins: Sugar beet ‘Labonita’ 0.11 mg/100 mL; Swiss chard ‘Lucullus,’ 0.09 mg/100 mL; fodder beet ‘Monro’ 0.15 mg/100 mL. In contrast with weed beets and beetroots, these varieties have a ratio of betacyanins to betaxanthins under 1.0, but the betaxanthin content was higher in beetcrops than in wild beet and can be used as an alternative to non-red varieties. Stability tests of selected varieties showed that storage at 22 °C for 6 h, or at 7 °C for 24 h, did not significantly reduce the betalain content in the samples.

Tailoring the Functional Potential of Red Beet Purées by Inoculation with Lactic Acid Bacteria and Drying

This study was focused on a comparative analysis of two drying methods, such as convective and infrared drying, on the red beetroot purées with lactic acid bacteria, as a strategy for tailoring the health benefits of the selected plant. For both varieties, the total betalain contents varied from 13.95 ± 0.14 mg/g dry weight in Beta vulgaris var. cylindra when compared with 11.09 ± 0.03 mg/g dry weight in Beta vulgaris var. vulgaris, whereas significant differences were found in total phenolic and flavonoid contents. Significant drying induced changes were found in selected bioactives, in terms of total betalains, flavonoids, and polyphenols, which influenced the antioxidant activities of the purées, structure, and color parameters. In general, infrared technology was more protective, leading to an increase of 20% in flavonoids content. One logarithmic decrease in cell viability was observed in all powders samples. After the in vitro digestion, the betalains decreased, in both gastric and intestinal simulated juices, with a more pronounced profile in infrared processed purées. Textural and rheological analysis of the dried purées highlighted that the infrared drying is milder compared to the conventional one, allowing us to obtain powders with enhanced functional properties, in terms of bioactives content, cell viability, color, and structural and rheological behavior.

Three Types of Red Beetroot and Sour Cherry Based Marmalades with Enhanced Functional Properties

The importance of bioactive compounds such as betalains and anthocyanins was highlighted in the present study by the valorization of red beetroot and sour cherry as an attempt to develop healthy products. The aim of the study was to obtain and characterize three types of marmalade based on red beetroot, sour cherry and both in 1:1 combination, obtained by heating at 95 °C for 30 min. Changes in total phenolic content, total flavonoids, betalains, anthocyanins and antioxidant activity were evaluated before and after the thermal treatment. Several other analyses such as color, rheological and textural analyses and confocal laser microscopy were performed to provide further information about the quality of the added-value food products. A significant decrease of 34% in betalains content was registered in the red beetroot marmalade due to the chemical changes in bioactives induced by the temperature. A satisfactory ABTS radical scavenging activity of 8.12 ± 0.38 mMol Trolox/g dry weight (dw) was obtained for the red beetroot and sour cherry based marmalade. The gelled structure was validated by the rheological and textural characteristics. The results highlighted the potential use of red beetroot and sour cherry as food raw materials, due to their particular profile of bioactive compounds.

Natural colourants analysis and biological activities. Association to molecular markers to explore the biodiversity of Opuntia species

INTRODUCTION

Synthetic colourants are subject to various allergies. As a result, the use of plant-based additives has proved promising.

OBJECTIVE

It is in this perspective that our objective was undertaken to investigate natural colourants from edible cactus. Opuntia species populations were single-sequence repeat (SSR) fingerprinted, the analysis of betalains and phenolic compounds and the evaluation of their biological potentials were also characterised.

RESULTS

Photometric quantification of betalains and phenols showed an interspecific variation across Opuntia species. Opuntia ficus indica fruits showed the highest betalain [betaxanthins; 843.67 and betacyanins; 1400 mg/100 g dry weight (DW)] and polyphenol contents. Reversed-phase high-performance liquid chromatography (RP-HPLC) analysis showed that the variation of individual phenols profile was influenced by interspecific and genetic factors. Isorhamnetin-O-(di-deoxyhexosyl-hexoside) was the major compound and its content varied according to Opuntia species, while catechol was the predominant phenolic compound in O. humifusa with 1.88 μg/g DW. Concerning cactus species, Opuntia colourants exhibited a potent antiradical activity [half maximal inhibitory concentration (IC₅₀ ) up to 1 μg/mL]. Opuntia species were effective against Gram-positive and Gram-negative bacterial strains [inhibition zone (IZ) up to 27 mm]. A high genetic diversity within Opuntia genotypes based on SSR markers was revealed. UPGMA (unweighted pair group method with arithmetic mean) dendrogram and PCoA (principal coordinate analysis) based on natural pigments and antimicrobial profiles indicated significant variation. The correlation approach proved the presence of a probably metabolic relationship between genetic markers, pigments and their biological activities.

CONCLUSION

A possible association between molecular approach and metabolic profile analysis of Opuntia allows tracing the relationship among species for its genetic conservation.

Identification and Determination of Betacyanins in Fruit Extracts of Melocactus Species

Betacyanin pigments were studied in edible fruits of four Melocactus species, M. violaceus Pfeiff., M. bahiensis (Britton & Rose) Luetzelb, M. amoenus (Hoffm.) Pfeiff., and M. curvispinus Pfeiff., by means of chromatographic and mass spectrometric techniques. The main pigment constituent, melocactin, endogenously present in the Melocactus species, was identified as betanidin 5-O-β-sophoroside betacyanin, previously known as "bougainvillein-r-I". The highest total concentration of betacyanins was found in fruits of M. amoenus (∼0.08 mg/g). Except for melocactin being the most abundant betacyanin (34.8-38.8%) in the analyzed species, a presence of its malonylated derivative, mammillarinin (15.2-19.9%), as well as more hydrophobic feruloyled and sinapoyled melocactins was confirmed by additional co-chromatographic experiments with authentic reference betacyanins. The acyl migration isomers of the malonylated betacyanins as well as a presence of 5''-O-E-sinapoyl-2'-O-apiosyl-betanin (2.3-3.0%) found frequently in light-stressed cacti was also acknowledged.

Leaves of White Beetroot As a New Source of Antioxidant and Anti-Inflammatory Compounds

The white beetroot cv. Śnieżna Kula is the first betanin-free beetroot registered in the European Union. The aim of this study was to compare the phenolic acids profile and antioxidant capacity of leaves of white (SK) and red (CC) beetroots and red (LC) and white (BL) Swiss chard growing in Poland. LC leaves were the richest source of total phenolics (16.55 mg GAE/g FW) and phenolic acids (1.81 mg/g FW), while the highest content of flavonoids was determined in CC leaves (1.6 mg QE/g FW). The highest antiradical activity was observed for LC, whereas CC extract exhibited the highest chelating power. BL and CC leaf extracts demonstrated high LOX inhibitory potential (EC50 = 53.23 and 56.97 mg FW/mL, respectively). An uncompetitive type of LOX inhibition was obtained for all extracts. SK extracts demonstrated the highest XO inhibitory activity (EC50 = 81.04 mg FW/mL). A noncompetitive type of XO inhibition was obtained in both extracts from red leaves (CC and LC), whereas an uncompetitive mode of inhibition was observed in the case of white leaf (SK and LC) extracts. Thus, it can be assumed that the presence of betanin influences the XO inhibition mechanism.