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

Extraction, stabilization, and health application of betalains: An update

Betalains are nitrogenous compounds principally produced by a select group of plants of the Caryophyllales order, characterized by the vibrant coloration on bracts, flowers, leaves, seeds, and fruits. Betalains are produced by tyrosine metabolism and derived from a common precursor: betalamic acid. They are categorized into two principal groups: betacyanins and betaxanthins. Their technological importance is of great interest to the food industry due to their role as a natural pigment. Still, in recent years, it also relied on its high biological potential such as free-radical scavenging, anti-inflammatory, anti-cancer, and anti-diabetic, among other applications. However, challenges related to their bioavailability and low stability have to be addressed. The review summarizes and analyses the most current advances in extraction methods to preserve their structure, the novel trends that guarantee their stability, and the most explored health applications of betalain extracts from various plant sources.

Development of stimuli-responsive cellulose textile finished with natural extract for detection of ammonia

The aim of this study is to develop an eco-friendly, flexible, sensitive, rapid-response, reversible, portable, cost-effective, and straightforward solid-state colorimetric smart cotton fabric (CF) designed as a vapochromic sensor for detecting ammonia. The natural Betalain (BTL) dye can be derived from Beta vulgaris L. (beetroot). The BTL dye was directly applied to cotton fibers in the presence of a mordant, resulting in the formation of a mordant/BTL coordinated complex nanoparticles. The molecular size, water solubility, sensitivity, and rapid response of BTL make them suitable indicator dyes for cellulose fibers, facilitating the development of diagnostic tests (BTL@CF) for gaseous and aqueous ammonia. The BTL-dyed fabric demonstrated a fast response within a fraction of a second, exhibiting a detection limit ranging from 5 to 400 mg/L. The BTL receptor exhibited ratiometric alterations in the absorption spectra, demonstrating hypsochromism from 574 to 403 nm with an isosbestic point of 477 nm when the ammonia concentration level increased in aqueous solutions. The diameters of the mordant/BTL nanoparticles were found to be 15-55 nm. No significant flaws were noticed in air permeability and bending length during the textile finishing process. The treated cotton fibers exhibited satisfactory colorfastness.

Inkjet-printed colorimetric indicators from the peels of red pitaya and Kyoho grape for the detection of food spoilage gases

The development of intelligent packaging materials can be alternative means to monitor food freshness and showcase real-time quality decline during storage. Colorimetric indicators are commonly employed as such examples due to their capability to exhibit chemically-responsive color changes triggered by the in-package headspace change during food deterioration. Different food-grade indicator dyes or pigments were investigated in literature, but one challenge was to incorporate the colorant into packaging materials with easy manipulation of indicator compositions. In this study, betanin extracted from red pitaya peel and anthocyanin extracted from Kyoho grape peel were developed into inks and subsequently printed as colorimetric indicators through piezoelectric inkjet printing. The formulated ink solution containing indicator compounds exhibited Newtonian fluid characteristic and was confirmed as printable fluid. The developed indicators showed detectable color responses upon the exposure of increasing levels of different food volatile gases including acetic acid, butyric acid, trimethylamine, ammonia and hexanoic acid. For each gas analyte present at low and high doses, the indicator's color responses can be differentiated by conducting the principal component analysis and hierarchical cluster analysis, with high sensitivity. A preliminary study on seafood freshness monitoring was conducted and visible color changes were observed during shrimp deterioration.

Valorization of Fruit and Vegetable Waste: An Approach to Focusing on Extraction of Natural Pigments

The increasing demand for functional foods has spurred interest in bioactive compounds, particularly their role in health promotion and disease prevention. This review comprehensively explores the bioavailability, mechanisms of action, and potential applications of bioactive compounds derived from natural food sources. We have systematically compiled and synthesized data from the recent scientific literature, including peer-reviewed journal articles, clinical studies, and meta-analyses, to present an in-depth evaluation of these compounds' physicochemical properties, stability, and interactions within food matrices. Furthermore, this review discusses advanced delivery systems, such as nanoencapsulation and emulsification, for enhancing bioavailability and targeted release. By addressing critical gaps in the understanding of the functional and technological aspects of bioactive compounds, this review underscores their relevance in formulating novel nutraceuticals and functional foods. The insights presented herein provide a foundation for future research and practical applications in the food industry, ultimately contributing to improving human health and well-being. Although recovering bioactive compounds from food waste is a sustainable way to reduce waste and use resources, additional research is required to make these procedures more efficient for use on an industrial scale.

Extraction and Analysis of Natural Color From Beetroot (Beta vulgaris L.) Using Different Techniques, and Its Utilization in Ice Cream Manufacturing

A rich source of natural color, beetroot (Beta vulgaris L. subsp. vulgaris) extracts and colorants offer deep red color to the dishes and boost their nutritional and antioxidant value. This research extracted beetroot color using Soxhlet, cold press, and ultrasonic methods. After testing the extracts for yield %, color (L*, a*, and b*), betalains, total polyphenols, and antioxidant activity, the colorant was used to make ice cream. The results of three techniques revealed that the extract obtained from Soxhlet extraction (SE) has more total phenolic content (244.11 mg GAE/100 g), DPPH free radical scavenging activity (23.41%), significantly higher yield (48.05%), and better color results, as compared to the other extraction techniques. However, the contents of betalains (399.47 mg/L) were observed more in the extract obtained from ultrasonic extraction (UE). The extract obtained after the SE technique was further utilized in the ice cream manufacturing to check its acceptability in this product, compared to the artificial color. Six samples of ice cream were developed having different ratios of beetroot-derived color and artificial color. Control ice cream (T0) contained artificial color, whereas ice cream (T5) was developed by replacing complete artificial color with beetroot-derived color. The other treatments (T1), (T2), (T3), and (T4) contained a combination of both natural and artificial colors with different proportions. Various quality parameters of these ice cream formulations, such as pH, acidity, brix, melting rate, overrun, and specific gravity, were studied. The result signified that the addition of beetroot color did not have a considerable effect on these attributes. The result of color analysis of ice cream suggested that the mean value of L* is higher in T5 (73.16), which only contains 0.1% beetroot color, and is lowest in T0 (65.24), which contains 0.1% artificial color. The addition of natural colorant resulted in a higher L* value. Sensory characteristics including color, mouth coating, flavor, aroma, texture, and overall acceptability of T5 showed more acceptance and significant results as compared to other treatments that contained artificial colors. Therefore, the beetroot-derived natural colorants could be employed to develop nutritional, healthy, and acceptable ice cream.

Exploring the Biochemical Profile of Beta vulgaris L.: A Comparative Study of Beetroots and Swiss Chard

In this study, leaves and roots from three beetroot cultivars (cv. Albina Vereduna (white roots), cv. Burpee's Golden (golden roots), and cv. Pablo F1 (red roots)), as well as Swiss chard leaves (also known as "rhubarb chard", or Beta vulgaris subsp. cicla var. flavescens) were evaluated in terms of their chemical profile and bioactive properties. Roots were characterized by high carbohydrate content, which also contributed to greater energy values. In contrast, fibers were the predominant macronutrient in leaves, followed by carbohydrates. In both leaves and roots, the most abundant organic acids were quinic and oxalic, while the major free sugar was sucrose. The profile of fatty acid varied between the studied plant parts, with saturated fatty acids prevailing in root samples, while leaves exhibited higher levels of polyunsaturated fatty acids. Regarding phenolic composition, a total of 19 compounds were tentatively identified in leaves (including derivatives of vitexin, isorhamnetin, quercetin, and ferulic, sinapic, and p-coumaric acids), while the roots exhibited a less diverse composition, with a total of eight compounds identified (e.g., derivatives of ferulic, sinapic, p-coumaric and caffeic acids). A total of eight betalains were also identified, out of which seven were classified as betacyanins and one as betaxanthin. The leaves of Swiss chard presented compounds from both classes, while the roots and leaves of cv. Pablo F1 were characterized only by the presence of betacyanins, and those of cv. Burpee's Golden only by betaxanthin. All samples exhibited relevant activity against Y. enterocolitica, L. monocytogenes, and S. aureus, although leaf samples demonstrated better antioxidant capacity. In conclusion, beetroot leaves outperformed their corresponding roots in terms of chemical composition, antioxidant, and antimicrobial activity, suggesting their high potential as nutrient-rich and functional ingredients in a diverse and well-balanced diet.

Microneedles as Modern Carriers of Plant Extracts

Recently, intensive research has been conducted on effective and simple systems for delivering active substances deep into the epidermis, e.g., for the treatment of skin inflammation. One possibility can be the use of soluble microneedles in which active compounds are encapsulated. This article describes the preparation of modern carriers, namely microneedles with encapsulated extracts of red beet or parsley leaves, that are rich in active substances with antioxidant and anti-inflammatory properties, specifically betanin and apigenin. The concentration of hyaluronic acid sodium salt, the method of preparing the solution, and the technique of the complete filling of molds were optimized. Plant extracts were obtained with sonication or maceration. In order to characterize the extracts obtained, several techniques were employed, such as UV-Vis, LC-MS, GC-MS, and FTIR-ATR. The analyses performed allowed for confirmation of the presence of selected active substances in the extracts. The most optimal solution of the microneedles' precursor turned out to be the one with a concentration of 10 wt.% of sodium hyaluronate, prepared by stirring and sonication. The most efficient extraction method for each plant was chosen, and the extracts were introduced into a solution of hyaluronic acid sodium salt. The resulting soluble microneedle patches can be used as an alternative to the traditional methods of delivering anti-inflammatory and antioxidant substances of plant origin.

Acute effects of beetroot extract and resveratrol ingestion on cardiovascular and cardiac autonomic modulation recovery after moderate-intensity aerobic exercise in individuals with coronary artery disease: a triple-blinded, randomized, placebo-controlled trial

PURPOSE

This study aimed to evaluate the acute effects of beetroot extract and resveratrol supplementation (isolated and combined) on cardiac autonomic modulation and cardiovascular parameters recovery after exercise in individuals with coronary artery disease (CAD).

METHODS

14 males with CAD were submitted to 4 protocols consisting of 30 min (min) of rest, 30 min of aerobic exercise on a treadmill (60% of the heart rate reserve HRR), followed by 30 min of recovery. Before each protocol, the subjects consumed 500 mg of starch (placebo protocol), 500 mg of beetroot (beetroot protocol), or 500 mg of resveratrol (resveratrol protocol), or 500 mg of beetroot and 500 mg of resveratrol (combined protocol). Heart rate variability (HRV) indices and cardiorespiratory parameters were determined at different times during the protocols.

RESULTS

Regarding HR, significantly higher values about rest in the placebo protocol at all recovery moments (1st to 30th min) were observed. Significant differences were observed in the other protocols (beetroot, resveratrol and combined) from the first to the 20th min recovery. For SBP, significantly higher values concerning rest were observed at the first minute of recovery for all protocols. No differences were found for the HRV index between time and protocols.

CONCLUSIONS

The single supplementation of beetroot and resveratrol (isolated and combined) did not alter HRV and cardiovascular parameter responses between protocols. The consumption of beetroot extract and resveratrol enhanced vagal modulation and heart rate recovery compared to rest.

Atriplex hortensis var. 'rubra' extracts and purified amaranthin-type pigments reduce oxidative stress and inflammatory response in LPS-stimulated RAW264.7 cells

The use of direct injection ion mobility mass spectrometry (DI-IM-MS) to detect and identify betacyanin pigments in A. hortensis 'rubra' extracts was explored for the first time, with results compared to conventional LC-MS/MS analysis. The anti-inflammatory activities of leaf and seed extracts, alongside purified amaranthin and celosianin pigments, were investigated using a model of lipopolysaccharide (LPS)-activated murine macrophages. Extracts and purified pigments significantly inhibited the production of prostaglandin E2 and NO by up to 90% and 70%, respectively, and reduced the expression of Il6, Il1b, Nos2, and Cox2. Leaf and seed extracts also decreased secretion of Il6 and Il1b cytokines and reduced protein levels of Nos2 and Cox2. Furthermore, extracts and purified pigments demonstrated potent dose-dependent radical scavenging activity in a cellular antioxidant activity assay (CAA) without any cytotoxic effects. Our research highlights the promising biological potential of edible, climate-resilient A. hortensis 'rubra' as a valuable source of bioactive compounds.

Bioactive compound encapsulation: Characteristics, applications in food systems, and implications for human health

Nanotechnology plays a pivotal role in food science, particularly in the nanoencapsulation of bioactive compounds, to enhance their stability, bioavailability, and therapeutic potential. This review aims to provide a comprehensive analysis of the encapsulation of bioactive compounds, emphasizing the characteristics, food applications, and implications for human health. This work offers a detailed comparison of polymers such as sodium alginate, gum Arabic, chitosan, cellulose, pectin, shellac, and xanthan gum, while also examining both conventional and emerging encapsulation techniques, including freeze-drying, spray-drying, extrusion, coacervation, and supercritical anti-solvent drying. The contribution of this review lies in highlighting the role of encapsulation in improving system stability, controlling release rates, maintaining bioactivity under extreme conditions, and reducing lipid oxidation. Furthermore, it explores recent technological advances aimed at optimizing encapsulation processes for targeted therapies and functional foods. The findings underline the significant potential of encapsulation not only in food supplements and functional foods but also in supportive medical treatments, showcasing its relevance to improving human health in various contexts.

Betalains: A Narrative Review on Pharmacological Mechanisms Supporting the Nutraceutical Potential Towards Health Benefits

Betalains are naturally occurring pigments sourced mainly from Beta vulgaris (beetroot), Hylocereus spp. (dragon fruit), Amaranthus spp., and Opuntia spp. Betalains are widely used for their vibrant colors and health-promoting properties. These nitrogenous, water-soluble pigments are crucial colorants in the food industry, responsible for the red, purple, and yellow plant tissues, predominantly in the order Caryophyllales. They are grouped into betacyanins, with reddish-violet hues, and betaxanthins, yellow to orange. Examples include beetroot stems for betacyanins and yellow pitaya pulp for betaxanthins. Several pharmacological activities were reviewed in the scientific literature, describing their potential implications for human health. In this review, we focused on the main and latest studies on the pharmacological effects and mechanisms of betalains, including antioxidant, anti-inflammatory, antihypertensive, hypolipidemic, antidiabetic, hepatoprotective, neuroprotective, anticancer, and antimicrobial properties, in both in vitro and in vivo studies. Overall, betalain consumption is considered safe, with no major adverse effects or allergic reactions reported. We also approached topics such as the pharmacokinetics, bioavailability, stability, and enhanced stabilization of betalains. This article provides a comprehensive overview of bioactive potential of betalains, highlighting the biochemical mechanisms involved. The current knowledge broadens the clinical applicability of betalains, making them potential sources of nutraceutical compounds that can be used to develop functional foods.

Beet Root Peel Extract as a Natural Cost-Effective pH Indicator and Food Preservative in Edible Film: Shelf Life Improvement of Cold-Stored Trout Fillet

In this study, chitosan (C)-polyvinyl alcohol (P) edible film containing bio-fabricated nanosilver particles (nAg) (as antimicrobial agent) and beetroot peel extract (BRPE) (as antioxidant agent and pH indicator) was used as spoilage indicator in cold-stored rainbow trout fillets. DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity (43.02%), reducing power (2.87), and total phenolic content (360.50 mg GAE/g) of ethanolic BRPE were higher than aqueous extract. Silver nanoparticles were biosynthesized using silver nitrate reduction by chitosan, confirmed by UV-Visible spectroscopy, optical and scanning electron microscope images, and X-ray diffraction analysis. The highest tensile strength (4.20 MPa) and elongation at break (118%) belonged to the CP-BRPE film, and the lowest water vapor permeability (2.45 10-5 g/s/m/P) was related to the CP-nAg film. Also, the lowest total viable count (6.17 log CFU/g), psychrotrophic bacteria (6.27 log CFU/g), Enterobacteriaceae (4.9 log CFU/g), pH (5.66), total volatile basic-nitrogen (TVB-N) (22.1 mg/100 g of fish), and thiobarbituric acid reactive substances (TBARS) (0.705 mg MDA/kg of fish) values of the packaged trout fillets were significantly (p ≤ 0.05) observed in CP-BRPE-gnAg treatment among the other treatments at the end of the storage period, and CP-gnAg, CP-BRPE, and CP treatments were in the next ranks, respectively. Colorimetric analysis of the used films showed that the films containing BRPE depicted color spectra of red to yellow at the same time as the spoilage symptoms initiated in the packaged fillets. It is concluded that BRPE not only increased the preservative effects of chitosan-polyvinyl alcohol film containing green silver nanoparticles but also can be considered as a natural cost-effective spoilage indicator of the rainbow trout fillets during cold storage time.

Pre-harvest application of sodium nitroprusside enhances storage root quality in red beet cultivated under normal and drought conditions

BACKGROUND

The role of nitric oxide (NO) in plant stress tolerance, as well as in increasing post-harvest quality, has been extensively demonstrated in several fruits and vegetable crops; however, the effects of its pre-harvest application on post-harvest quality are still poorly documented. Therefore, the pre-harvest application of NO in red beet (Beta vulgaris subsp. vulgaris) plants cultivated under well-watered and drought conditions was evaluated to assess whether it improves the post-harvest quality of their storage roots. Red beet plants cultivated under well-watered (80% of water holding capacity) or drought condition (15% of water holding capacity) were sprayed weekly with water (control) or 100 μmol L-1 sodium nitroprusside (SNP), an NO donor. Sixty-six days after sowing, red beet roots were harvested, and root yield, total sugar yield, reducing sugars, non-reducing sugars, proteins, lipids, root ashes, root moisture, soluble solids, titratable acidity, pH, vitamin C, total phenolics, total betalains, betacyanins, betaxanthins and antioxidant capacity were determined.

RESULTS

While drought led to a reduction in root yield, sugars, lipids and titratable acidity, it increased phenolic compounds, betalains and the antioxidant capacity of beets. SNP reversed the negative effects of drought on sugar, lipid and organic acid contents and increased antioxidant capacity independent of stress.

CONCLUSION

Pre-harvest SNP treatment reversed drought-induced yield reductions in beets, while boosting bioactive compounds and antioxidant capacity. It also enhanced vitamin C content independently, indicating its dual role in stress mitigation and beet quality improvement. Future research should explore other crops and stress conditions. © 2024 Society of Chemical Industry.

Recent Advances of Cellulose-Based Hydrogels Combined with Natural Colorants in Smart Food Packaging

Due to the frequent occurrence of food safety problems in recent years, healthy diets are gradually receiving worldwide attention. Chemical pigments are used in smart food packaging because of their bright colors and high visibility. However, due to shortcomings such as carcinogenicity, people are gradually looking for natural pigments to be applied in the field of smart food packaging. In traditional smart food packaging, the indicator and the packaging bag substrate have different degrees of toxicity. Smart food packaging that combines natural colorants and cellulose-based hydrogels is becoming more and more popular with consumers for being natural, non-toxic, environmentally friendly, and renewable. This paper reviews the synthesis methods and characteristics of cellulose-based hydrogels, as well as the common types and characteristics of natural pigments, and discusses the application of natural colorants and cellulose-based hydrogels in food packaging, demonstrating their great potential in smart food packaging.

Impact of thermal processing on phytochemical profile and cardiovascular protection of Beta vulgaris L. in hyperlipidemic rats

Beetroot (Beta vulgaris L.) is globally recognized for its outstanding color and flavor. It has been acknowledged for its therapeutic value since the ancient Romans. It is used to treat cardiovascular disorders. The therapeutic benefits of red beetroot are due to the substantial amounts of various bioactive metabolites, such as ascorbic acid, carotenoids, nitrates, phenolics, and betalains. However, the bioavailability and shelf life of these substances are significantly affected by the considerable variations in their processing methods among different countries. The longevity of the extracts is prolonged by employing well-established preservation techniques, such as boiling and steaming, which involve the application of heat. Our study aimed to analyze and compare the phytochemical composition of raw and heat processed beetroot using UPLC-QTOF-MS/MS. In addition, the study aimed to assess the effectiveness of processed beetroot in protecting against cardiovascular complications in a rat model of obesity induced by high-fat diet (HFD). UPLC-QTOF-MS/MS phytochemical profiling revealed the presence of 51 compounds, including organic acids, flavonoids, phenolics, betanins, and saponins. All the extracts demonstrated a significant decline in MDA, TNF- α, and IL-6 levels, suppressed the TGF-β expression, and restored the serum catalase level to normal. Among all the tested extracts, the steamed extract exhibited the slightest percentage change in body weight (10.2 ± 6.4) and effectively lowered the TNF-α level to normal levels. In contrast, the normal histological structure of heart muscle fibers was notably preserved in the cardiac sections of rats pretreated with steamed and boiled beetroot extracts. Additionally, mild caspase-3 immunoreactivity was observed in the cardiac muscles. The current study demonstrated that the steamed beetroot extract showed improved cardioprotective properties compared to the fresh and boiled extracts.

Betalains from vegetable peels: Extraction methods, stability, and applications as natural food colorants

Betalains are hydrophilic pigments naturally present in a limited number of plants and fungi. In addition to providing pigmentation, ranging from yellow to red, they show potential for replacing artificial food colorings. Betalains can be obtained from agri-food waste like vegetable peels through conventional and emerging extraction methods; however, they are susceptible to chemical changes due to various degradation factors, such as the presence of oxygen, light, and increased temperature. In this context, encapsulation can be used as a strategy to stabilize and reduce the pigment degradation rate for later industrial application in processed foods. This study reviews data from the last five years on the production and relevance of valuing agri-food waste, in addition to research carried out on betalains obtained from vegetable peels, such as extraction methods, encapsulation as a method of controlling stability and applications as colorant in food matrices, highlighting news insights for the field of pigments from plant sources. This review shows that encapsulation techniques using mixtures of wall materials offer superior protection than isolated materials. Despite advances in applicability, gaps still persist regarding stability in food matrices, especially on an industrial scale. However, future investigations should focus on filling the gaps regarding the maintenance of the properties of betalains for application in food industries as natural food coloring based on the precepts of circular economy and sustainable technology.

Studying the Influence of Salt Concentrations on Betalain and Selected Physical and Chemical Properties in the Lactic Acid Fermentation Process of Red Beetroot

This study emphasizes the significance of optimizing salt content during the fermentation of red beetroot to produce healthier and high-quality fermented products. It investigates the impact of different salt levels on fermentation, analyzing various parameters such as pH levels, dry matter content, total acidity, salt content, color changes, pigment content, and lactic acid bacteria count. This study identifies the most favorable salt concentration for bacterial growth during fermentation and storage as 2-3%. It was evaluated that salt levels fluctuated significantly during fermentation, with nearly 50% of the added salt absorbed by the beetroot tissues, mainly when lower salt concentrations were used. The fermentation process had a negative effect on the content of betalain pigments, as well as yellow pigments, including vulgaxanthin-I. It was also found that fermentation and storage affected the proportions of red pigments, with betacyanins proving to be more stable than betaxanthins, and that salt addition affected negatively pH and total acidity while causing an increase in yellow color. The pH was negatively correlated with the duration of the process, the amount of red pigment, and bacterial count. The results indicate that lower salt levels can lead to favorable physicochemical and microbiological parameters, allowing for the production of fermented red beetroot with reduced salt content without compromising quality.

Research Progress on Bioactive Substances of Beets and Their Functions

As a globally cultivated and economic crop, beets are particularly important in the cane sugar and feed industries. Beet pigments are among the most important natural pigments, while various chemical components in beets display beneficial biological functions. Phenolic substances and betalains, as the main bioactive compounds, determine the functional characteristics of beets. This review categorizes the basic types of beets by the chemical composition of bioactive substances in their leaves, stems, and roots and emphatically summarizes the research progress made on the functions of two major substances in different types of beets: phenolic compounds and betalain pigments. This study provides useful insights for the comprehensive and effective application of beets in the health food and pharmaceutical industries.

Evaluating Biocompounds in Discarded Beetroot (Beta vulgaris) Leaves and Stems for Sustainable Food Processing Solutions

The current trend focuses on reducing food waste, with scientific studies exploring the nutritional value of discarded food components to identify potential health benefits. Beetroot (Beta vulgaris L.) is highly consumed, but its stems and leaves are often discarded. This work aims to characterize the chemical properties and bioactive compounds in beet stems and leaves and assess their applicability in food products. The stems and leaves were subjected to different drying temperatures (50 to 70 °C) to determine the optimal temperature for preserving their bioactive compounds. They are then nutritionally and physiochemically characterized and incorporated into a food matrix. The optimal drying temperature was 60 °C. The leaves and stems contain approximately 30 and 15 g/100 g of protein, 30 and 32 g/100 g of dietary fiber, 4 and 0.45 g/100 g of lipids, and 24 and 25 g/100 g of ash, respectively. Both provide approximately 50% of the amino acid requirements established by the WHO/FAO/UNU and are rich in iron and potassium. The stems presented 53% more betalainic compounds (0.58 mg/g) and a higher nitrate content (359 mg/kg) than did the leaves, which presented a higher polyphenol content. The incorporation of flour from beet stems and leaves into food products is economical, reduces food waste, and enhances nutrition and health.

Beta vulgaris Betalains Mitigate Parasitemia and Brain Oxidative Stress Induced by Plasmodium berghei in Mice

Although many drugs have been discovered to treat malaria infection, many of them face resistance from the host's body with long-term use. Therefore, this study aimed to evaluate the activity of betalains (from Beta vulgaris) and chloroquine (a reference drug) against brain oxidative stress induced by Plasmodium berghei in male mice. Two protocols were applied in this study: the therapeutic and prophylactic protocols. The results of the therapeutic protocol revealed a significant decrease in the level of parasitemia caused by P. berghei. Additionally, the histopathological changes in various brain regions were markedly improved after treatment with betalains. Regarding the prophylactic protocol, betalains were able to protect the brain tissues from oxidative stress, inflammation, and disrupted neurotransmitters expected to occur as a result of infection by P. berghei. This was demonstrated by modulating the activities of brain antioxidants (SOD and GSH), inflammatory cytokines (IL-6, IL-10, IL-12, TNF-α, and INF-γ), and neurotransmitters (serotonin, epinephrine, and norepinephrine). This study has proven that using betalains as a treatment or as a preventive has a vital and effective role in confronting the brain histopathological, oxidative stress, and inflammatory changes induced by P. berghei infection.

Natural Pigments Recovery from Food By-Products: Health Benefits towards the Food Industry

Given the health risks associated with synthetic colorants, natural pigments have emerged as a promising alternative. These renewable choices not only provide health benefits but also offer valuable technical and sensory properties to food systems. The effective application of natural colorants, however, requires the optimization of processing conditions, exploration of new sources, and development of novel formulations to ensure stability and maintain their inherent qualities. Several natural pigment sources have been explored to achieve the broad color range desired by consumers. The purpose of this review is to explore the current advances in the obtention and utilization of natural pigments derived from by-products, which possess health-enhancing properties and are extracted through environmentally friendly methods. Moreover, this review provides new insights into the extraction processes, applications, and bioactivities of different types of pigments.

Protecting meat color: The interplay of betanin red and myoglobin through antioxidation and coloration

Myoglobin (Mb) responsible for meat color is easily oxidized resulting in meat discoloration. Here, betanin red (BR), as a natural pigment and antioxidant, was chosen for enhancing redness and inhibiting oxidation. Multiple spectroscopies, isothermal titration calorimetry and molecular docking demonstrated that BR changed the microenvironment of heme group and amino acid residues of Mb, inhibited the oxidation of oxymyoglobin. The main interaction force was hydrogen bond and one variable binding site provided a continuous protective barrier to realize antioxidation. The combination of antioxidation with the inherent red color of BR offered dual color protection effect on processed beef with the addition amount of 0.2 % BR. BR treatment enhanced the redness by 25.59 ∼ 53.24 % and the sensory acceptance by 4.89 ∼ 14.24 %, and decreased the lipid oxidation by 0.58 ∼ 15.92 %. This study paves a theoretical basis for the application of BR and its structural analogues in meat color protection and other quality improvement.

pH-dependent stability of major betalains in the encapsulated beetroot extracts (Beta vulgaris L.)

Betalain is a water-soluble pigment contained in Caryophyllales plants. It not only holds potential as a natural food colorant but also offers various health benefits, acting as an antioxidant. This study focused on analyzing the pH-dependent stability of encapsulated betalain pigments extracted from red beetroot (Beta vulgaris L.) using methods such as absorption spectroscopy, HPLC, and LC-MS. The major pigments identified were vulgaxanthin I, betanin, isobetanin, and neobetanin, alongside minor components, including three betaxanthin species and a degradation product known as betalamic acid. Spectrophotometric analyses revealed that above pH 8, the betalain peak at 435 nm decreased and red-shifted to a peak at 549 nm, a shift that could be reversed through neutral pH treatment. At pH 11, a new broad peak appeared at 410 nm and was identified as betalamic acid. To assess the pH-dependency of each betalain, the targeted betalains were separated and quantified through HPLC after incubation across a wide pH range of 2-11 and during storage. After 3 days of storage in highly alkaline conditions (pH 10-11), major betalains, with the exception of neobetanin, underwent significant degradation. Conversely, these pigments displayed relative stability in acidic conditions. In contrast, neobetanin showed vulnerability to acidic conditions but exhibited tolerance to alkaline pH levels of 10-11. The degradation product, betalamic acid, demonstrated a similar susceptibility to alkaline pH as betanins. In conclusion, the significant stability decrease under highly alkaline conditions results not only from the hydrolytic reaction of betalains but also from the degradation of betalamic acid itself. PRACTICAL APPLICATION: Encapsulation methods are used to enhance the stability of betalains against temperature variations; however, the effects of pH, especially when considering individual betalain species, are not well understood. Despite betalains exhibiting similar features and being suitable for a wide pH range from acid to alkaline conditions, they are significantly affected by alkaline pH levels exceeding 10, as well as by storage duration. This study demonstrated the application of encapsulation to pH-dependent stability, and the findings offer valuable insights and a fresh perspective on betalains as red biocolorants, extending their potential application to a wide range of pH-controlled food products.

A review on mechanisms and impacts of cold plasma treatment as a non-thermal technology on food pigments

Food characteristics like appearance and color, which are delicate parameters during food processing, are important determinants of product acceptance because of the growing trend toward more diverse and healthier diets worldwide, as well as the increase in population and its effects on food consumption. Cold plasma (CP), as a novel technology, has marked a new trend in agriculture and food processing due to the various advantages of meeting both the physicochemical and nutritional characteristics of food products with minimal changes in physical, chemical, nutritional, and sensorial properties. CP processing has a positive impact on food quality, including the preservation of natural food pigments. This article describes the influence of CP on natural food pigments and color changes in vegetables and fruits. Attributes of natural pigments, such as carotenoids, chlorophyll, anthocyanin, betalain, and myoglobin, are presented. In addition, the characteristics and mechanisms of CP processes were studied, and the effect of CP on mentioned pigments was investigated in recent literature, showing that the use of CP technology led to better preservation of pigments, improving their preservation and extraction yield. While certain modest and undesirable changes in color are documented, overall, the exposure of most food items to CP resulted in minor loss and even beneficial influence on color. More study is needed since not all elements of CP treatment are currently understood. The negative and positive effects of CP on natural food pigments in various products are discussed in this review.

Investigating the effect of red beetroot powder concentration and processing time on the bioactive compounds composition and antioxidant capacity of beetroot dark chocolate

BACKGROUND

The development of functional foods is receiving increased recognition as a result of the general interest in healthy diets as part of a healthier lifestyle. This project sought to incorporate red beetroot in dark chocolate and investigate the effect of beetroot powder concentration and processing time on the chocolates' bioactive compound composition, antioxidant capacity, and sugar content.

RESULTS

The results showed the presence of bioactive compounds such as betalains and vitamin C in the red beetroot with relatively high antioxidant capacity. The addition of beetroot powder to dark chocolate increased the majority of the bioactive compounds (e.g. catechin, epicatechin, betalains, vitamin C) while at the same time increasing the antioxidant capacity. It also resulted in a decrease in sugar content. Except for vitamin C, processing for more than 12 h had an increasing effect on the majority of the bioactive compounds. Beetroot powder incorporation at a maximum of 30% and processing for 24 h was regarded as optimal.

CONCLUSION

Overall, the present study suggests that red beetroot powder could be added to dark chocolates and processed for more than 12 h to increase the bioactive compounds and overall antioxidant capacity. This research would help to diversify beetroot utilization, reduce post-harvest losses, and improve the overall health-promoting properties of dark chocolate for improved consumer well-being. © 2023 Society of Chemical Industry.

Identification, expression analysis of quinoa betalain biosynthesis genes and their role in seed germination and cold stress

Betalains provide Chenopodium quinoa bright color, and the key enzyme genes for betalain biosynthesis include CYP76AD, DODA, and GTs. In this study, 59 CqCYP76AD, CqDODA and CqGTs genes in quinoa were identified and characterized by gene structural characteristics, phylogenetic relationships and gene expression patterns. The CqCYP76AD genes were divided into ɑ, β and γ types, CqDODA into ɑ and β types, and CqGTs into CqcDOPA5GT, CqB5GT and CqB6GT types according to phylogenetic relationships. The analysis of co-linearity identified eight pairs of duplicated genes which were subjected to purifying selection during evolution. CqCYP76AD and CqDODA, as well as CqcDOPA5GT and CqB5GT may have been evolutionarily linked in genetic inheritance, based on gene location and gene structure study. The tissue expression specificity of CqCYP76AD, CqDODA, and CqGTs genes in response to seed germination and cold stress was studied by RNA-Seq data. The genes CqCYP76AD, CqDODA, and CqGTs were involved in betalain biosynthesis and cold stress. CqCYP76AD, CqDODA, CqcDOPA5GT and CqB5GT gene sequences were consistent in the eight quinoa samples and showed significant variations in expression. In contrast, the inconsistency between changes in gene expression and betalain accumulation indicates that other factors may influence betalain biosynthesis in quinoa. This study offers the theoretical basis for the roles of the CqCYP76AD, CqDODA, and CqGTs genes in betalain biosynthesis and cold stress in quinoa, as well as a guide for the full utilization of betalains in quinoa plants.

Novel ammonia-sensitive sodium alginate-based films containing Co-Imd microcrystals for smart packaging application

Currently, there is an urgent requirement for the fabrication of smart packaging materials that can be applied for the real-time visual monitoring of food freshness. In this research, cubic Co-MOF (Co-Imd) microcrystal with ammonia-sensitivity and antibacterial activity was manufactured and then anchored within sodium alginate (NaAlg) matrix to construct smart packaging materials. The structure, physical and functional performances of NaAlg-based films with different content of Co-Imd (0.5, 1.0 and 2.0 wt% on NaAlg basis) were then evaluated in detail. Results reveal that the incorporated Co-Imd fillers are equally anchored within the NaAlg matrix due to the generation of new hydrogen-bonding interaction, which make an obvious improvement in mechanical strength, toughness, oxygen/water barrier, and UV-blocking ability of the NaAlg film. Moreover, the constructed NaAlg/Co-Imd blend films show superior antibacterial capability, ammonia-sensitivity function as well as color stability. Ultimately, the NaAlg/Co-Imd blend films were successfully utilized for indicating the deterioration of shrimp based on noticeable color alteration, suggesting their tremendous prospects for utilization in smart active packaging. This work offers a facile and efficient method for fabricating novel ammonia-sensitive and long-term color-stable NaAlg-based film materials with improved mechanical strength, toughness, oxygen/water barrier, UV-blocking, and antibacterial performances for smart active packaging application.

Co-production of pigment and high value-added bacterial nanocellulose from Suaeda salsa biomass with improved efficiency of enzymatic saccharification and fermentation

This study evaluated the co-production of pigment and bacterial nanocellulose (BNC) from S. salsa biomass. The extraction of the beet red pigment reduced the salts and flavonoids contents by 82.7%-100%, promoting the efficiencies of enzymatic saccharification of the biomass and the fermentation of BNC from the hydrolysate. SEM analysis revealed that the extraction process disrupted the lignocellulosic fiber structure, and the chemical analysis revealed the lessened cellulase inhibitors, consequently facilitating enzymatic saccharification for 10.4 times. BNC producing strains were found to be hyper-sensitive to NaCl stress, produced up to 400.4% more BNC from the hydrolysate after the extraction. The fermentation results of BNC indicated that the LDU-A strain yielded 2.116 g/L and 0.539 g/L in ES-M and NES-M, respectively. In comparison to the control, the yield in ES-M increased by approximately 20.0%, while the enhancement in NES-M was more significant, reaching 292.6%. After conducting a comprehensive characterization of BNC derived from S. salsa through Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Thermogravimetric Analysis (TGA), the average fiber diameter distribution of these four BNC materials ranges from 22.23 to 33.03 nanometers, with a crystallinity range of 77%-90%. Additionally, they exhibit a consistent trend during the thermal degradation process, further emphasizing their stability in high-temperature environments and similar thermal properties. Our study found an efficient co-production approach of pigment and BNC from S. salsa biomass. Pigment extraction made biomass more physically and chemically digestible to cellulase, and significantly improved BNC productivity and quality.

The Antioxidant Activity of Betanin protects MRC-5 cells Against Cadmium Induced Toxicity

Cadmium (Cd) can induce both acute and chronic effects in the lungs depending on the time and the exposure route. Betanin is a component derived from the roots of red beets and it is well-known for its antioxidant and anti-apoptosis effects. The current study aimed to survey the protective effects of betanin on cell toxicity induced by Cd. Different concentration of Cd alone and in combination with betanin was assessed in MRC-5 cells. The viability and oxidative stress were measured using resazurin and DCF-DA methods respectively. Apoptotic cells were assessed by PI staining of the fragmented DNA and western blot analysis detected the activation of caspase 3 and PARP proteins. Cd exposure for 24 h declined viability and increased ROS production in MRC-5 cells compared to the control group (p < 0.001). Also, Cd (35 μM) elevated DNA fragmentation (p < 0.05), and the level of caspase 3-cleaved and cleaved PARP proteins in MRC-5 cells (p < 0.001). Co-treatment of cells with betanin for 24 h significantly enhanced viability in concentrations of 1.25 and 2.5 μM (p < 0.001) and 5 μM (p < 0.05) and declined ROS generation (1.25 and 5 μM p < 0.001, and 2.5 μM p < 0.01). As well as, betanin reduced DNA fragmentation (p < 0.01), and the markers of apoptosis (p < 0.001) compared to the Cd-treated group. In conclusion, betanin protects lung cells against Cd-induced toxicity through antioxidant activity and inhibition of apoptosis.

Unveiling Alternative Oxidation Pathways and Antioxidant and Cardioprotective Potential of Amaranthin-Type Betacyanins from Spinach-like Atriplex hortensis var. 'Rubra'

A comprehensive oxidation mechanism was investigated for amaranthin-type betacyanins with a specific glucuronosylglucosyl moiety isolated from Atriplex hortensis 'rubra' using liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (LC-DAD-ESI-MS/MS) and LC-Quadrupole-Orbitrap-MS (LC-Q-Orbitrap-MS). By employing one-dimensional (1D) and two-dimensional (2D) NMR, this study elucidates the chemical structures of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS)-oxidized celosianins for the first time. These findings demonstrate alternative oxidation pathways for acylated betacyanins compared to well-known betanidin, betanin, and gomphrenin pigments. Contrary to previous research, we uncover the existence of 17-decarboxy-neo- and 2,17-bidecarboxy-xanneo-derivatives as the initial oxidation products without the expected 2-decarboxy-xan forms. These oxidized compounds demonstrated potent free radical scavenging properties. Celosianin (IC50 = 23 μg/mL) displayed slightly higher antioxidant activity compared to oxidized forms, 17-decarboxy-neocelosianin (IC50 = 34 μg/mL) and 2,17-bidecarboxy-xanneocelosianin (IC50 = 29 μg/mL). The oxidized compounds showed no cytotoxic effects on H9c2 rat cardiomyoblasts (0.1-100 μg/mL). Additionally, treatment of H9c2 cells with the oxidized compounds (0.1-10 μg/mL) elevated glutathione levels and exhibited protective effects against H2O2-induced cell death. These findings have significant implications for understanding the impact of oxidation processes on the structures and biological activities of acylated betalains, providing valuable insights for future studies of the bioavailability and biological mechanism of their action in vivo.

Combining Conventional Organic Solvent Extraction, Ultrasound-Assisted Extraction, and Chromatographic Techniques to Obtain Pure Betanin from Beetroot for Clinical Purposes

Red beetroot extract (E162) is a natural colorant that owes its color to betanin, its major red pigment. Betanin displays remarkable antioxidant, anti-inflammatory, and chemoprotective properties mediated by its structure and influence on gene expression. However, the betanin employed in most preclinical assays is a beetroot extract diluted in dextrin, not pure betanin, as no isolated compound is commercially available. This makes its use inaccurate concerning product content estimates and biological effect assessments. Herein, a combination of conventional extraction under orbital shaking and ultrasound-assisted extraction (UAE) to purify betanin by semi-preparative HPLC was performed. The employed methodology extracts betalains at over a 90% yield, achieving 1.74 ± 0.01 mg of pure betanin/g beetroot, a 41% yield from beetroot contents increasing to 50 %, considering the betalains pool. The purified betanin exhibited an 85% purity degree against 32 or 72% of a commercial standard evaluated by LC-MS or HPLC methods, respectively. The identity of purified betanin was confirmed by UV-Vis, LC-MS, and 1H NMR. The combination of a conventional extraction, UAE, and semi-preparative HPLC allowed for betanin purification with a high yield, superior purity, and almost three times more antioxidant power compared to commercial betanin, being, therefore, more suitable for clinical purposes.

Chitosan-Based Nanogels Designed for Betanin-Rich Beetroot Extract Transport: Physicochemical and Biological Aspects

Nanotechnology has emerged as a possible solution to improve phytochemicals' limitations. The objective of the present study was to encapsulate beetroot extract (BR Ext) within a chitosan (CS)-based nanogel (NG) designed via ionic crosslinking with tripolyphosphate (TPP) for betanin (Bet) delivery, mainly in the ophthalmic environment. BR Ext is rich in betanin (Bet) according to thin layer chromatography (TLC), UV-visible spectroscopy, and HPLC analysis. NG presented a monodisperse profile with a size of 166 ± 6 nm and low polydispersity (0.30 ± 0.03). ζ potential (ζ-Pot) of +28 ± 1 is indicative of a colloidally stable system. BR Ext encapsulation efficiency (EE) was 45 ± 3%. TEM, with the respective 3D-surface plots and AFM, showed spherical-elliptical-shaped NG. The BR Ext release profile was biphasic with a burst release followed by slow and sustained phase over 12 h. Mucoadhesion assay demonstrated interactions between NG with mucin. Moreover, NG provided photoprotection and pH stability to BR Ext. FRAP and ABTS assays confirmed that BR Ext maintained antioxidant activity into NG. Furthermore, in vitro assays using human retinal cells displayed absence of cytotoxicity as well as an efficient protection against injury agents (LPS and H2O2). NGs are a promising platform for BR Ext encapsulation, exerting controlled release for ophthalmological use.

Multipronged Approach to Profiling Metabolites in Beta vulgaris L. Dried Pulp Extracts Using Chromatography, NMR and Other Spectroscopy Methods

Beetroot (Beta vulgaris L.) is known for being a rich source of phytochemicals, minerals and vitamins. This study aims to show how the combination of extraction/chromatography/mass spectrometry and NMR offers an efficient way to profile metabolites in the extracts of beetroot. Such combination may lead to the identification of more nutritional or medicinal compounds in natural products, and it is essential for our ongoing investigation to study the selective adsorption/desorption of these metabolites' on/off nanoparticles. The aqueous and organic extracts underwent analyses using UV-vis spectroscopy; GC-MS; LC-MS; 1H, 13C, 31P, TOCSY, HSQC, and selective TOCSY NMR experiments. Polar Extract: The two forms of betalain pigment were identified by UV-vis and LC MS. Fourteen amino acids, sucrose, and other compounds, among which is riboflavin, were identified by LC-MS. Two-dimensional TOCSY showed the spin coupling correlations corresponding to some of these compounds. The HSQC spectrum showed 1H/13C spin correlation in sucrose, confirming its high abundance in beetroot. Organic Extract: GC-MS data enabled the identification of several compounds including six fatty acid methyl esters (FAME) with higher than, on average, 90% similarity score. Selective TOCSY NMR data showed the spin coupling pattern corresponding to oleic, linoleic, and linolenic fatty acids. 31P NMR spectra indicate that phospholipids exist in both the organic and aqueous phase.

Encapsulation of betalain-rich extract from beetroot postharvest waste using a binary blend of gum Arabic and maltodextrin to promote a food circular bioeconomy

Introduction

The present study evaluated the potential of maltodextrin (MT), gum Arabic (GA), and their blends to produce functional beetroot waste extract powder (BWEP).

Methods

The beetroot waste extracts were produced using 50% ethanol and encapsulated using 10% (1:10, w/v) of the GA and MT carriers at different blending ratios, namely, GA:MT 1:0, GA:MT 0:1, GA:MT 1:1, GA:MT 2:1, and GA:MT 1:2, respectively. The BWEP were analyzed for physicochemical, technofunctional, morphological, crystallinity, and antioxidant properties.

Results

BWEP produced using either GA or MT exhibited better color, solubility, encapsulation efficiency, and betalain content. Powders from the blends of GA and MT showed better oil holding capacity and total phenolic content. On the other hand, powder yield, total soluble solids, titratable acidity, bulk density, and DPPH radical scavenging activity did not significantly differ (p > 0.05) among the powders. BWEP produced using GA and MT separately was relatively smaller and more regular compared to the powders from the blended biopolymers. All powders showed signs of agglomeration, which was more pronounced in the powders from the blended biopolymers. A total of 16 metabolites, including betalains (9), phenolic acids (2), and flavonoids (5), were tentatively identified. The majority of the metabolites were entrapped in the BWEP produced using GA and MT separately. The quantified metabolites included gallic acid (33.62-44.83 μg/g DM), (+)-catechin (32.82-35.84 μg/g DM), (-)-epicatechin (37.78-45.89 μg/g DM), and myricetin (30.07-35.84 μg/g DM), which were significantly higher in the BWEP produced from GA or MT separately.

Discussion

The study showed that although blending GA and MT has the potential to improve the quality of BWEP, using these biopolymers separately showed a promise to promote a food circular bioeconomy.

Development of a multifunctional food packaging for meat products by incorporating carboxylated cellulose nanocrystal and beetroot extract into sodium alginate films

Consumers' pursuit for safe meat products is challenging to develop smart food packaging with proper mechanical properties and multifunctional properties. Therefore, this work attempted to introduce carboxylated cellulose nanocrystal (C-CNC) and beetroot extract (BTE) into sodium alginate (SA) matrix films to enhance their mechanical properties and endow them with antioxidant properties and pH-responsive capacity. The rheological results showed the C-CNC and BTE were consistently dispersed in the SA matrix. The incorporation of C-CNC made the surface and cross-section of the films rough but still dense, thus significantly improving the mechanical properties of the films. The integration of BTE provided antioxidant properties and pH responsiveness without significantly changing the thermal stability of the film. The highest tensile strength (55.74 ± 4.52 MPa) and strongest antioxidant capacities were achieved for the SA-based film with BTE and 10 wt% C-CNC. Additionally, the films possessed higher UV-light barrier properties after incorporating BTE and C-CNC. More notably, the pH-responsive films discolored when TVB-N value exceeded 18.0 mg/100 g during storage of pork at 4 °C and 20 °C, respectively. Therefore, the SA-based film with enhanced mechanical and functional properties has a high potential for quality detection in smart food packaging applications.

Preparation, Characterization, and Application of pH-Response Color-Changeable Films Based on Pullulan, Cooked Amaranth (Amaranthus tricolor L.) Juice, and Bergamot Essential Oil

Pullulan-based smart packaging films were prepared by mixing cooked amaranth juice and bergamot essential oil. The impact of cooked amaranth juice and bergamot essential oil on the color-changeability, structural characterization, and barrier, antioxidant, mechanical and thermal properties of pullulan-based films was determined. Results showed the cooked amaranth juice contained pH-response color-changing betacyanins. The pullulan films containing cooked amaranth juice were color-changeable in pH 9-12 buffers and in ammonia vapor. The color-changeable property of betacyanins in cooked amaranth juice was unaffected by bergamot essential oils. The inner structure of pullulan films was greatly affected by cooked amaranth juice, forming big and ordered humps in film cross-sections. The crystallinity of pullulan films was improved by the combined addition of cooked amaranth juice and bergamot essential oil. Among the films, the pullulan film containing cooked amaranth juice and 6% bergamot essential oil showed the highest UV-vis light barrier property, antioxidant activity, and tensile strength; while the pullulan film containing cooked amaranth juice and 4% bergamot essential oil showed the highest oxygen barrier property and thermal stability. Moreover, the pullulan films containing cooked amaranth juice were able to monitor the freshness of shrimp by presenting color changes from reddish purple to dark red.

A comprehensive review of recent development in extraction and encapsulation techniques of betalains

Betalains are attractive natural pigments with potent antioxidant activity, mainly extracted from the roots, tubers, leaves, flowers, and fruits of certain plants and some fungi. They constitute a reliable alternative to synthetic dyes used in the food industry and are considered toxic for consumers. In addition, there is convincing evidence of their health benefits for consumers. However, betalains are highly unstable to environment factors, such as light, heat, oxygen, water activity, and pH change which can be degraded during food processing, handling, storage, or delivery. Therefore, newly developed extraction methods and micro/nano-encapsulation techniques are currently applied to enhance the extraction yield, solve their instability problems, and improve their application in the food industry. This article aims to summarize the new advanced extraction methods of betalains, discussing the recent encapsulation techniques concerning the different encapsulating materials utilization. Betalains, natural pigments with potent antioxidant activity, are increasingly extracted from the roots, tubers, leaves, flowers, and fruits of certain plants and some fungi as safe alternatives to synthetic food dyes used in the food industry. However, their susceptibility to degradation during food processing, storage, and delivery poses challenges. Recent developments in extraction methods (e.g., supercritical fluid, pressurized liquid, ultrasound- and microwave-assisted, and enzyme-assisted) enhance betalain recovery, minimizing degradation. Encapsulation techniques using biopolymers, proteins, lipids, and nanoparticles protect betalains from environmental factors, extending shelf life and enabling controlled release. These advancements offer improved extraction efficiency, reduced solvent use, shorter processing times, and enhanced stability. Integration of these techniques in the food industry presents opportunities for incorporating betalains into various products, including functional foods, beverages, and dietary supplements. By addressing stability challenges, these developments support the production of innovative, healthier food items enriched with betalains. This article provides an overview of recent advancements in betalain extraction and encapsulation, highlighting their potential applications in the food industry.

Azo dyes in the food industry: Features, classification, toxicity, alternatives, and regulation

Azo dyes, including Tartrazine, Sunset Yellow, and Carmoisine, are added to foods to provide color, but they have no value with regard to nutrition, food preservation, or health benefits. Because of their availability, affordability, stability, and low cost, and because they provide intense coloration to the product without contributing unwanted flavors, the food industry often prefers to use synthetic azo dyes rather than natural colorants. Food dyes have been tested by regulatory agencies responsible for guaranteeing consumer safety. Nevertheless, the safety of these colorants remains controversial; they have been associated with adverse effects, particularly due to the reduction and cleavage of the azo bond. Here, we review the features, classification, regulation, toxicity, and alternatives to the use of azo dyes in food.

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.

Metabolic Biomarkers of Red Beetroot Juice Intake at Rest and after Physical Exercise

BACKGROUND

Red beetroot is known to be a health-promoting food. However, little attention is placed on intestinal bioactive compound absorption. The aim of the study was to assess the urinary red beetroot juice (RBJ) intake biomarkers and possible differences in RBJ's micronutrient absorption at rest or after physical exercise.

METHODS

This is a three-armed, single-blind study, involving seven healthy volunteers which were randomly divided into three groups and alternatively assigned to three experimental sessions: RBJ intake at rest, RBJ intake with physical activity, and placebo intake with physical activity. For each session, urine samples were collected before and 120, 180, and 240 min after the intake of RBJ or placebo. The same sampling times were employed for the experimental session at rest. The RBJ metabolic composition was also characterized to identify the urinary biomarkers derived from the intake.

RESULTS

4-methylpyridine-2-carboxylic acid, dopamine-3-O-sulfate, glutamine, and 3-hydroxyisobutyrate were identified as RBJ intake biomarkers. Physical activity significantly increased only the dopamine-3-O-sulfate excretion 120 min after RBJ intake.

CONCLUSIONS

Urinary dopamine-3-O-sulfate is related to RBJ dopamine content, while 4-methylpyridine-2-carboxylic acid is a betanin or betalamic acid catabolite. The different excretions of these metabolites following physical activity suggest a possible effect on the RBJ uptake depending on different transport processes through the mucosa, namely diffusion-mediated transport for dopamine and saturable transcellular transport for betalamic acid derivatives. These results open new perspectives in improving the absorption of natural bioactive molecules through physical activity.

Antioxidant Capacity, Nitrite and Nitrate Content in Beetroot-Based Dietary Supplements

Due to the high content of bioactive substances, beetroot and its preserves might be a valuable constituent of a diet. Research into the antioxidant capacity and content of nitrate (III) and (V) in beetroot-based dietary supplements (DSs) worldwide is limited. The Folin-Ciocalteu method, CUPRAC, DPPH, and Griess methods were used to determine total antioxidant capacity, total phenolic content, nitrites, and nitrates content in fifty DSs and twenty beetroot samples. Moreover, the safety of products was evaluated because of the concentration of nitrites, nitrates, and the correctness of labelling. The research showed that a serving of fresh beetroot provides significantly more antioxidants, nitrites, and nitrates than most daily portions of DSs. Product P9 provided the highest dose of nitrates (169 mg/daily dose). However, in most cases, the consumption of DSs would be associated with a low health value. The acceptable daily intake was not exceeded in the cases of nitrites (0.0015-0.55%) and nitrates (0.056-48%), assuming that the supplementation followed the manufacturer's recommendation. According to European and Polish regulations, 64% of the products tested did not meet all the requirements for labelling food packaging. The findings point to the need for tighter regulation of DSs, as their consumption might be dangerous.

Food Wastes and Microalgae as Sources of Bioactive Compounds and Pigments in a Modern Biorefinery: A Review

The United Nations 2030 Agenda for Sustainable Development has created more pressure on countries and society at large for the development of alternative solutions for synthetic and fossil fuel derived products, thus mitigating climate change and environmental hazards. Food wastes and microalgae have been studied for decades as potential sources of several compounds that could be employed in various fields of application from pharmaceutical to textile and packaging. Although multiple research efforts have been put towards extracting rich compounds (i.e., phenolic compounds, tocopherols, and tocotrienols) from these sources, they still remain overlooked as two major sources of bioactive compounds and pigments, mainly due to inefficient extraction processes. Hence, there is a growing need for the development of optimized extraction methods while employing non-organic solvent options following the main principles of green chemistry. This review will focus on delivering a clear and deep analysis on the existing procedures for obtaining bioactive compounds and pigments from food wastes derived from the most consumed and produced fruit crops in the world such as apples, oranges, cherries, almonds, and mangoes, and microalgal biomass, while giving light to the existing drawbacks in need to be solved in order to take full advantage of the rich properties present in these two major biorefinery sources.

Complexation of anthocyanins, betalains and carotenoids with biopolymers: An approach to complexation techniques and evaluation of binding parameters

Natural pigments are bioactive compounds that can present health-promoting bioactivities in the human body. Due to their strong coloring properties, these compounds have been widely used as color additives as an alternative to artificial colorants. However, since these pigments are unstable under certain conditions, such as the presence of light, oxygen, and heat, the use of complexation and encapsulation techniques with biopolymers is in demand. Moreover, some functional properties can be achieved by using natural pigments-biopolymers complexes in food matrices. The complexation and encapsulation of natural pigments with biopolymers consist of forming a complex with the aim to make these compounds less susceptible to oxidative and degrading agents, and can also be used to improve their solubility in different media. This review aims to discuss different techniques that have been used over the last years to create natural pigment-biopolymers complexes, as well as the recent advances, limitations, effects, and possible applications of these complexes in foods. Moreover, the understanding of thermodynamic parameters between natural pigments and biopolymers is very important regarding the complex formation and their use in food systems. In this sense, thermodynamic techniques that can be used to determine binding parameters between natural pigments and potential wall materials, as well as their applications, advantages, and limitations are presented in this work. Several studies have shown an improvement in many aspects regarding the use of these complexes, including increased thermal and storage stability. Nonetheless, data regarding the biological effects on the human body and the sensory acceptance of natural pigments-biopolymers complexes in food systems are scarce in the literature.

The Generation of Nitric Oxide from Aldehyde Dehydrogenase-2: The Role of Dietary Nitrates and Their Implication in Cardiovascular Disease Management

Reduced bioavailability of the nitric oxide (NO) signaling molecule has been associated with the onset of cardiovascular disease. One of the better-known and effective therapies for cardiovascular disorders is the use of organic nitrates, such as glyceryl trinitrate (GTN), which increases the concentration of NO. Unfortunately, chronic use of this therapy can induce a phenomenon known as "nitrate tolerance", which is defined as the loss of hemodynamic effects and a reduction in therapeutic effects. As such, a higher dosage of GTN is required in order to achieve the same vasodilatory and antiplatelet effects. Mitochondrial aldehyde dehydrogenase 2 (ALDH2) is a cardioprotective enzyme that catalyzes the bio-activation of GTN to NO. Nitrate tolerance is accompanied by an increase in oxidative stress, endothelial dysfunction, and sympathetic activation, as well as a loss of the catalytic activity of ALDH2 itself. On the basis of current knowledge, nitrate intake in the diet would guarantee a concentration of NO such as to avoid (or at least reduce) treatment with GTN and the consequent onset of nitrate tolerance in the course of cardiovascular diseases, so as not to make necessary the increase in GTN concentrations and the possible inhibition/alteration of ALDH2, which aggravates the problem of a positive feedback mechanism. Therefore, the purpose of this review is to summarize data relating to the introduction into the diet of some natural products that could assist pharmacological therapy in order to provide the NO necessary to reduce the intake of GTN and the phenomenon of nitrate tolerance and to ensure the correct catalytic activity of ALDH2.

Sustainable Production and Characteristics of Dried Fermented Vegetables

The current fashion for healthy food and the increasing number of people with lactose intolerance make fermented vegetables increasingly important. On top of this, surpluses unused in the vegetable harvest can become a potential source of “green waste”. The use of fermentation and freeze-drying can result in a valuable, sustainable product that can solve the problems of spoiled vegetables and the need for refrigerated storage. Therefore, this study aimed to obtain sustainable dried fermented vegetables and to compare their selected physical and structural properties. Beetroot, carrot, and red pepper were selected for this purpose. These vegetables were subjected to a spontaneous lactic fermentation process. After the process, the vegetables were freeze-dried, and their structure and selected properties (color, dry weight, and the number of lactic acid bacteria) were determined. Fermented vegetables were found to differ from their raw sources in structure and color, the main discrepancies being shown by the b* factor (yellow-blue). Root vegetables had smaller pores of structure in the freeze-dried samples than red peppers. The freeze-drying process did not affect the number of bacteria. It can be concluded that both the fermentation and the freeze-drying processes affected the structure of the selected vegetables. All tested vegetables can be fermented and freeze-dried without major changes in color and microbiological properties and can be used as a potential source of lactic acid bacteria and health-promoting pigments, e.g., in the form of chips. In addition, their shelf life is extended.