Metabolic engineering of betacyanin in vegetables for anti-inflammatory therapy.

Betalains, which consist of the subgroups betaxanthins and betacyanins, are hydrophilic pigments that have classically been used for food colorants. Owing to their strong antioxidant property, their usefulness for application for therapeutic use is also expected. In addition, as betalains are mainly naturally available from plants of the order Caryophyllales, including beet (Beta vulgaris), metabolic engineering for betalain production in crops such as vegetables, fruits and cereals may provide new food resources useful for healthcare. Here we conducted metabolic engineering of betacyanins in tomato fruits and potato tubers. The transgenic tomato fruits and potato tubers with coexpression of betacyanin biosynthesis genes, CYP76AD1 from B. vulgaris, DOD (DOPA 4,5-dioxygenase) and 5GT (cyclo-DOPA 5-O-glucosyltransferase) from Mirabilis jalapa, under control of suitable specific promoters, possessed dark red tissues with enriched accumulation of betacyanins (betanin and isobetanin). The anti-inflammatory activity of transgenic tomato fruit extract was superior to that of wild-type fruit extract on macrophage RAW264.7 cells stimulated with lipopolysaccharide (LPS), as a result of decreased LPS-stimulated transcript levels of proinflammatory genes. These findings were in accord with the observation that administration of the transgenic tomato fruits ameliorated dextran sulfate sodium (DSS)-induced colitis as well as body weight loss and disease activity index in mice, via suppression of DSS-stimulated transcript levels of pro-inflammatory genes, including Tnf (encoding TNF-alpha), Il6, and Ptgs2 (encoding cyclooxygenae 2). Intriguingly, given the fact that the transgenic potato tuber extract failed to enrich the anti-inflammatory activity of macrophage cells, it is likely that metabolic engineering of betacyanins will be a powerful way of increasing the anti-inflammatory property of ordinary foods such as tomato.

Influence of High-Pressure Homogenization on the Physicochemical Properties and Betalain Pigments of Red Beetroot (Beta vulgaris L.) Juice.

High-pressure homogenization (HPH) is considered an innovative and modern method of processing and preserving liquid and semi-liquid foods. The aim of this research was to examine the impact of HPH processing on the content of betalain pigments and physicochemical properties of beetroot juice. Combinations of the following HPH parameters were tested: the pressure used (50, 100, 140 MPa), the number of cycles (1 and 3) and the applied cooling or no cooling. The physicochemical analysis of the obtained beetroot juices was based on the determination of the extract, acidity, turbidity, viscosity and color values. Use of higher pressures and a greater number of cycles reduces the turbidity (NTU) of the juice. Moreover, in order to maintain the highest possible extract content and a slight color change of the beetroot juice, it was crucial to perform sample cooling after the HPH process. The quantitative and qualitative profiles of betalains have been also determined in the juices. In terms of the content of betacyanins and betaxanthins, the highest values were found in untreated juice at 75.3 mg and 24.8 mg per 100 mL, respectively. The high-pressure homogenization process resulted in a decrease in the content of betacyanins in the range of 8.5-20.2% and of betaxanthins in the range of 6.5-15.0%, depending on the parameters used. Studies have shown that that the number of cycles was irrelevant, but an increase in pressure from 50 MPa to 100 or 140 MPa had a negative effect on pigment content. Additionally, juice cooling significantly limits the degradation of betalains in beetroot juice.

Bioaccessibility of Betalains in Beetroot (Beta vulgaris L.) Juice under Different High-Pressure Techniques.

The influence of high hydrostatic pressure (HHP) and supercritical carbon dioxide (SCCD) on the bioaccessibility of betalains in beetroot (Beta vulgaris L.) juice was investigated. Freshly squeezed juice (FJ) was treated at a mild temperature of 45 °C for 10 min (T45), pasteurization at 85 °C for 10 min (T85), HHP at 200, 400, and 500 MPa at 20 °C for 5 min (HHP200, HHP400, HHP500) and SCCD at 10, 30 and 60 MPa at 45 °C for 10 min (SCCD10, SCCD30, SCCD60). The juice was subjected to an in vitro digestion system equipped with dialysis. The content of betalains was measured with the aid of a High-Performance Liquid Chromatography (HPLC), the antioxidant capacity (AC) (ABTS•+, DPPH•) was analyzed during each digestion step, and the bioaccessibility of betacyanins and betaxanthins was assessed. The SCCD at 30 and 60 MPa significantly increased pigments' bioaccessibility compared with other samples. The 30 MPa proved particularly advantageous, as it increased the bioaccessibility of the total betacyanins and the betaxanthins by 58% and 64%, respectively, compared to the T85 samples. Additionally, higher bioaccessibility of betacyanins was noted in HHP200 and HHP400, by 35% and 32%, respectively, compared to FJ, T45, and T85 samples. AC measured by ABTS•+ and DPPH• assays were not unequivocal. However, both assays showed significantly higher AC in SCCD60 compared to T85 (21% and 31%, respectively). This research contributed to the extended use of the HHP and/or SCCD to design food with higher health-promoting potentials.

Betacyanin as Bioindicator Using Time-Temperature Integrator for Smart Packaging of Fresh Goat Milk.

Smart packaging is a packaging system with embedded sensor or indicator technology, which provides information on the quality of the product, especially perishable foods such as goat milk. One application of smart packaging is to use a time-temperature bioindicator. The purpose of this study was to determine the quality of fresh goat milk during storage at freezing temperatures (-20 ± 2°C) for 31 days and room temperature (25 ± 3°C) for 24 hours using a time-temperature indicator by utilizing a natural dye betacyanin. The method used was descriptive analysis, and the data obtained were processed using the correlation regression test. The samples were observed at freezing temperature every 24 hours and room temperature at 0, 1, 2, 3, 4, 5, 6, 8, 10, and 24 hours. The observation criteria consisted of changes in bioindicator color, milk pH, and total microbes. The results showed that color changes of the bioindicator film at room temperature were more noticeable than at freezing temperature. Based on changes in color of the bioindicator at room temperature, the sample was safe for consumption until the 5th hour with pH 6.51, and the biofilm color characteristics were L∗ = 82.49, a∗ = 21.46, and b∗ = -7.33, but the total number of microbes did not fulfil Indonesian National Standard at the 24th hour, i.e., 1.36 × 106 CFU/ml. At freezing temperatures, fresh goat milk was still safe for consumption until the 31st day with pH 6.51 and total microbe of 1.89 × 105 CFU/ml, and the biofilm color characteristics were L∗ = 80.52, a∗ = 24.15, and b∗ = -7.91. The results of this study concluded that the milk expiration limit based on the betacyanin indicator was 5 hours at room temperature and 31 days at freezing temperature.

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.

Application of Natural Pigments in Ordinary Cooked Ham.

The possibility of obtaining a carmine or pink color on ordinary cooked ham by applying natural dyes from three plant species, namely red radish (Raphanus sativus L.), hibiscus (Roselle sabdariffa L.) and red beetroot (Beta vulgaris L.), was investigated. The extracts were evaluated for the stability at physical-chemical parameters and subjected to cytotoxicity assays in the gastric cell line AGS Encapsulation of the extracts in soybean lecithin liposomes and maltodextrin microcapsules was performed. Lyophilized extracts before and after encapsulation in maltodextrin were applied in the formulation of ordinary cooked ham and used in a pilot scale of production. The color of cooked ham samples from different assays was evaluated visually and by colorimetry. The results suggest that the coloration of ordinary cooked ham obtained with extracts of red beetroot is very promising for future applications in this type of meat product.

Implications of the Red Beet Ripening on the Colour and Betalain Composition Relationships.

The evolution during ripening of Beta vulgaris (var. Pablo) on colour and betalain composition, not previously conducted in conjunction in red beets, has been examined. According to the results, it could be asserted that the ripening stage significantly (p < 0.05) influenced on all the studied parameters. On the basis of the betalain content, the optimum ripening stage corresponded to a medium weigh-to-calibre ratio, in the light of the significantly (p < 0.05) higher content of betalains, especially betanin and vulgaxanthin I. Moreover, colour attributes also differed during ripening, having the medium-ripened beetroots a significantly (p < 0.05) more reddish hue (hab) and lower lightness (L*), probably due to the higher content of betaxanthins in this stage. The colour differences among red beets in the stage II and the rest of stages were visually appreciable (ΔE*ab > 3) and mainly qualitative. A new range of opportunities for diversification of colorant market, from a nutritional and colorimetric point of view, could be possible by employing red beets with different stages of ripening.

Comparative Study of Betacyanin Profile and Antimicrobial Activity of Red Pitahaya (Hylocereus polyrhizus) and Red Spinach (Amaranthus dubius).

Betacyanins are reddish to violet pigments that can be found in red pitahaya (Hylocereus polyrhizus) and red spinach (Amaranthus dubius). This study investigated the impact of sub-fractionation (solvent partitioning) on betacyanin content in both plants. Characterization of betacyanins and evaluation of their antimicrobial activities were also carried out. Betanin was found in both plants. In addition, isobetanin, phyllocactin and hylocerenin were found in red pitahaya whereas amaranthine and decarboxy-amaranthine were found in red spinach. Sub-fractionated red pitahaya and red spinach had 23.5 and 121.5 % more betacyanin content, respectively, than those without sub-fractionation. Sub-fractionation increased the betanin and decarboxy-amaranthine content in red pitahaya and red spinach, respectively. The betacyanin fraction from red spinach (minimum inhibitory concentration [MIC] values: 0.78-3.13 mg/mL) demonstrated a better antimicrobial activity profile than that of red pitahaya (MIC values: 3.13-6.25 mg/mL) against nine Gram-positive bacterial strains. Similarly, the red spinach fraction (MIC values: 1.56-3.13 mg/mL) was more active than the red pitahaya fraction (MIC values: 3.13-6.25 mg/mL) against five Gram-negative bacterial strains. This could be because of a higher amount of betacyanin, particularly amaranthine in the red spinach.

Exploring the potential of red pitaya pulp (Hylocererus sp.) as a plant-based matrix for probiotic delivery and effects on betacyanin content and flavoromics.

This study evaluated the potential of red pitaya pulp fermented with Lacticaseibacillus paracasei subsp. paracasei F-19 (F-19) as a base for probiotic products. Physicochemical parameters, sugar, betacyanin, and phenolic contents, and antioxidant activity were analyzed over 28 days at 4 °C and compared to a non-fermented pulp, and to a pulp fermented with Bifidobacterium animalis subsp. lactis BB-12 (BB-12). Volatile compounds were identified using HS-SPME/GC-MS. Probiotic viability during storage and survival through in vitro-simulated gastrointestinal tract (GIT) stress were assessed. Red pitaya pulp, rich in moisture (85.83 g/100 g), carbohydrates (11.65 g/100 g), and fibers (2.49 g/100 g), supported fermentation by both strains. F-19 and BB-12 lowered pH, with F-19 showing stronger acidification, and maintained high viability (8.85-8.90 log CFU/mL). Fermentation altered sugar profiles and produced unique volatile compounds, enhancing aroma and sensory attributes. F-19 generated 2-phenylethanol, a unique flavor compound, absent in BB-12. Phenolic content initially increased but antioxidant activity decreased during storage. Betacyanin remained stable for up to 14 days. Red pitaya improved F-19 viability through the simulated GIT, while BB-12 populations significantly decreased (p < 0.05). These results suggest red pitaya pulp is a promising plant-based matrix for F-19, offering protection during digestion and highlighting its potential as a functional food with enhanced bioactive compound bioavailability and sensory attributes.

Physical, chemical, and antioxidant activity characterization of pitaya (Stenocereus pruinosus) fruits.

Fruits with red and orange flesh of the columnar cactus pitaya (Stenocereus pruinosus) were studied to evaluate physical characteristics, total soluble solids, betalains and soluble phenols content, and antioxidant activity. Fruits had, in average, weight of 179.0 g, 9.8 °Brix, 9.4 % carbohydrates, 1.25 % protein, 0.11 % ethereal extract, 0.60 % crude fiber, and 0.62 % ash. Also, fruits resulted rich in Fe (22.8-27.8 mg/kg). Hue angle and contents of betacyanins, betaxanthins (µg/g dry sample), and total soluble phenols (mg GAE/g fresh sample) were 19.8°, 2860.0, 3210.0, and 1.6 in the red material, and 28.9°, 470.0, 2670.0, and 1.2, respectively, in the orange fruit. The antioxidant capacity was higher in the red material, since the ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)) technique reported 1090.6 and 735.4 µmol of Trolox equivalents/g fresh flesh in red and orange fruits, respectively, while the oxygen radical absorbance capacity (ORAC) assay reported 7.84 and 5.16 µmol of Trolox equivalents/g fresh flesh, respectively. The chromatographic profile showed five betalains in red fruits, but only four of them were observed in those orange fleshed.

Characterization of betalain-loaded liposomes and its bioactive potential in vivo after ingestion.

Betalains are plant pigments characterized by showing a wide range of beneficial properties for health. Its bioactive potential has been studied for the first time after its encapsulation in liposomes and subsequent administration to the animal model Caenorhabditis elegans. Phenylalanine-betaxanthin and indoline carboxylic acid-betacyanin encapsulated at concentrations of 25 and 500 µM managed to reduce lipid accumulation and oxidative stress in the nematodes. Highly antioxidant betalains dopaxanthin and betanidin were also included in the survival analyses. The results showed that phenylalanine-betaxanthin was the most effective betalain by increasing the lifespan of C. elegans by 21.8%. In addition, the administration of encapsulated natural betanidin increased the nematodes' survival rate by up to 13.8%. The preservation of the bioactive properties of betalains manifested in this study means that the stabilization of the plant pigments through encapsulation in liposomes can be postulated as a new way for administration in pharmacological and food applications.

Chemical characterization of yellow-orange and purple varieties of Opuntia ficus-indica fruits and thermal stability of their betalains.

Betalains are plant pigments with biological properties and can be used instead of synthetic colorants to confer color and functional properties to foods. The objective of this work was to carry out the chemical characterization of two varieties of prickly pear of Opuntia ficus-indica, one of yellow-orange coloration (Mandarina) and the other of purple coloration (Vigor), through measurements of chemical parameters and color in pulp, antioxidant activity, total phenolic compounds, and betalain content. Considering the thermolability of betalains and their potential applications in food, the thermal stability and activation energy of betacyanins from Vigor variety and betaxanthins from the Mandarina variety were also evaluated and compared with those from beetroot, the main source of betalains. Results for chemical characterization agreed with previous prickly pear reports of other regions, while the thermal degradation kinetics of betalains showed a first-order degradation pattern with respect to time and temperature treatment. Betacyanins from Vigor prickly pear showed similar thermal stability to those from beetroot, which was reflected in similar values of activation energy, while betaxanthins from Mandarina prickly pear showed a higher stability, and therefore a higher activation energy, than those from beetroot. Based on the results, the prickly pear varieties used in this study can be considered as a good source of betalains with potential applications in food and, in addition, the methodology for the evaluation of thermostability can be used to compare the stability of betalains from different sources in a temperature range of 50-90°C. PRACTICAL APPLICATION: The varieties of prickly pear used in this study can be considered a good source of red-purple and yellow-orange easily extractable pigments. In addition, we report a methodology that can be used for the evaluation of the thermal stability of these pigments and to compare this stability between different plant sources. Gaining knowledge on betalain thermal stability will make it possible to propose specific applications, for example, in processed foods requiring different pigment stabilities.

Bioactive compounds and antioxidant activity in garambullo fruit (Myrtillocactus geometrizans) at different ripening stages.

Garambullo (Myrtillocactus geometrizans) is endemic in México, and although popularly consumed locally, its nutritional characteristics and value have not been studied in details. The objective of this work was to investigate the bioactive compounds and antioxidant activity in garambullo fruit from different sites at three ripening stages. Fruit from the three ripening stages (red, purple, and dark purple) were investigated for their physicochemical characteristics, hydrophilic (phenolic compounds, betalains, and ascorbic acid), and lipophilic (carotenoids, tocopherols, and fatty acids) bioactive compounds, using spectrophotometry, gas chromatography (GC-FID), and high-pressure liquid chromatography coupled to mass spectrometry (HPLC/DAD-ESI-MS). The antioxidant capacity was measured with the 2,2'-diphenyl-1-picrylhydrazyl and the ferric-ion-reducing antioxidant power assays. The color components of the fruit, chroma and a* values increased, whereas lightness (L*) and b* significantly decreased during ripening. Five betacyanins and four betaxanthins were tentatively identified with HPLC/DAD-ESI-MS, and betacyanins were more abundant than betaxanthins. Betalains content and antioxidant capacity of hydrophilic extracts significantly increased during ripening. Ten phenolic compounds were identified, with ferulic acid being the most abundant. Tocopherols were low (0.023-0.033 mg/100 g fw). Five fatty acids were abundant, and linoleic acid was the most important. Phenolic compounds, ascorbic acid, total carotenoids, and fatty acids decreased during fruit ripening. Garambullo fruit is rich in phytochemical compounds of importance for human nutrition and health. PRACTICAL APPLICATION: The physicochemical and bioactive compounds characterization in garambullo fruit is important to establish maturation and harvesting indices, postharvest strategies to preserve fruit quality and prolong postharvest life, promote the consumption and utilization of the fruit, and the designing of proper functional foods. In addition, the knowledge on the bioactive components might be useful to include this fruit in personalized nutritional approaches for patients with risks of certain chronic diseases. The methodology used in this study could be useful for the study of other fruits, especially those from the Cactaceae family.

Blood pressure-lowering effects of beetroot juice and novel beetroot-enriched bread products in normotensive male subjects.

A number of vegetables have a high nitrate content which after ingestion can be reduced to nitrite by oral bacteria, and further to vasoprotective NO endogenously. In the present study, two separate randomly controlled, single-blind, cross-over, postprandial studies were performed in normotensive volunteers. Ambulatory blood pressure (BP) was measured over a 24 h period following consumption of either four doses of beetroot juice (BJ), 0, 100, 250 and 500 g (n 18), or three bread products, control bread (0 g beetroot), red beetroot- and white beetroot-enriched breads (n 14). Total urinary nitrate/nitrite (NO(x)) was measured at baseline, and at 2, 4 and 24 h post-ingestion. BJ consumption significantly, and in a near dose-dependent manner, lowered systolic BP (SBP, P < 0·01) and diastolic BP (DBP, P < 0·001) over a period of 24 h, compared with water control. Furthermore, bread products enriched with 100 g red or white beetroot lowered SBP and DBP over a period of 24 h (red beetroot-enriched bread, P <0·05), with no statistical differences between the varieties. Total urinary NO(x) significantly increased following the consumption of 100 g (P < 0·01), 250 g (P <0·001) and 500 g BJ (P <0·001) and after red beetroot-enriched bread ingestion (P <0·05), but did not reach significance for white beetroot-enriched bread compared with the no-beetroot condition. These studies demonstrated significant hypotensive effects of a low dose (100 g) of beetroot which was unaffected by processing or the presence of betacyanins. These data strengthen the evidence for cardioprotective BP-lowering effects of dietary nitrate-rich vegetables.

Betacyanin and other antioxidants production during growth of Opuntia stricta (Haw.) fruits.

Mature cactus pears from Opuntia stricta have a dark purple color due to high betacyanin concentration, whose biosynthesis is initiated with the amino acid L-tyrosine as a primary precursor. This study followed the maturation and ripening processes of Opuntia stricta fruits to harvest them at high betacyanin and other antioxidant concentrations. Fruits lasted 9 months for final ripening. Physical and compositional changes at different maturation and ripening stages have been determined. Thus, ripe fruits were around 4.72 ± 0.10 cm length, 2.94 ± 0.05 cm diameter and 22.71 ± 0.20 g weight; moisture and pH were maintained at 87.05 ± 0.19 % and 3.37 ± 0.12, respectively. Purple pigment production started in the ovary of immature fruits four months after anthesis (MAA). Concentration of all analyzed metabolites increased from immature (4 MAA) until ripe (9 MAA) stage. In ripe fruits, reducing sugars were 4.72 ± 0.54 g/100 g ff and total phenols 135.17 ± 0.68 mg gallic acid/100 g ff. Metabolites identified by HPLC were the betacyanins: betanin (60.17 ± 1.08 mg/100 g ff), isobetanin (7.58 ± 0.94 mg/100 g ff) and betanidin (13.48 ± 0.87 mg/100 g ff). Also, L-ascorbic acid (35.03 ± 1.06 mg/100 g ff) and L-tyrosine (4.43 ± 0.73 mg/100 g ff) were determined. Furthermore, the addition of L-tyrosine or L-dopa to fruit pulp of moderately ripe fruits, increased betacyanin concentrations 17 (103.3 ± 3.8 mg/100 g) and 32 % (114.3 ± 4.1 mg/100 g), respectively.

Studies on the storage stability of betacyanins from fermented red dragon fruit (Hylocereus polyrhizus) drink imparted by xanthan gum and carboxymethyl cellulose.

Red dragon fruit is rich in health-benefited betacyanins that are susceptible to degradation. The present study was to improve the fermented red dragon fruit drink (FRDFD) betacyanins stability by incorporating hydrocolloids solution of xanthan gum (XG, 0.15-0.30%, w/v) and carboxymethyl cellulose (CMC, 0.3-0.5%, w/v) to produce Improved-FRDFD-dH2O. Results revealed the viscosities of all samples were significantly increased as the hydrocolloids concentration increased. All the samples' pH, aw, total soluble solids (TSS) and betacyanins content were not significantly affected by the hydrocolloids solution added. After four-week storage (25 °C), the formulation of 0.3% XG and 0.5% CMC had significantly reduced the betacyanins degradation from 60.55% to 30.66%. Meanwhile, all samples added with 0.3% XG and 0.3-0.5% CMC remained no significant change in viscosity, pH, aw and TSS after storage. These conclude the hydrocolloids solution of 0.3% XG and 0.5% CMC successfully stabilise the betacyanins in the FRDFD at 25 °C over four-week storage.

Betalains nanodispersions: Effects on betalains stability and on rheological properties of Greek yogurt.

Red beetroot (Beta vulgaris L.) is a great source of betalains. The main betalains are the betacyanins, responsible for the purple color, and betaxanthins, which present a brownish color. These pigments can present antioxidant activity and are very unstable under certain conditions, such as temperature, extreme ranges of pH, and exposure to light. The aim of this work was to obtain beetroot extract (BE) via ultrasound and transform it into nanoparticles by using polyethylene glycol (PBE) and polyethylene glycol with low molecular weight chitosan (PCBE) as dispersants. The stability of the main betalains in the nanodispersions and the effects of the nanodispersions on the color and rheological properties of commercial Greek yogurt were evaluated. Compared to pristine BE, PCBE nanoparticles presented increased stability for the main betalains in acidic conditions (pH 3.0 and 5.0) of 56% and 22%, respectively. Both PBE and PCBE showed enhanced relative thermal stability compared to pristine BE. Furthermore, PCBE improved commercial Greek yogurt's rheological properties and color parameters. PCBE nanodispersions can be successfully applied as a color additive to commercial Greek yogurt.

The impacts of peel inclusion and fermentation temperature on the bioactive compounds, antioxidant activity, and sensory properties of dragon fruit wines.

BACKGROUND: Even though dragon fruit peel has more health benefits than its pulp, it is considered to be waste after fruit processing. In this study, dragon fruit peel was explored as an additional ingredient in winemaking. METHODS: The contents of total phenolic compounds, betacyanins and ascorbic acid, the antioxidant capacity by DPPHz method, and the level of consumer acceptability of the wines prepared from two species with and without peel were compared. RESULTS: The wines of the H. polyrhizus species contained much higher total phenolics (1.4-1.6 times), betacyanins (75-81 times), and vitamin C (2.8-3.8 times), as well as higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (1.2 times) than the wines of H. undatus. Although the fermentation process led to the degradation of betacyanins, it increased the total phenolics (up to 17%), vitamin C (up to 24%), and DPPHz scavenging activity (up to 19%) as compared with the control when fermentation was conducted at 25°C, which was found as the most suitable fermentation temperature to produce wines with the highest quality in terms of antioxidant content and activity. At this temperature, peel inclusion also increased these values in the wine. In addition, the sensory properties in terms of appearance and aroma could be improved in the final fermented product. CONCLUSIONS: H. polyrhizus wine might have higher antioxidant properties than H. undatus wine. With a suitable fermentation temperature, peel inclusion as an ingredient could enhance these characteristics of the wine without compromising its sensory quality. This study may provide insights into fruit winemaking with higher health benefits.

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

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

Characterization of the profile and concentration of betacyanin in the gastric content, blood and urine of rats after an intragastric administration of fermented red beet juice.

The aim of the study was to evaluate the profile and level of betacyanins in the gastric content, blood (portal and main veins) and urine of rats after an intragastric administration of fermented red beet juice with various betacyanin doses. Samples were collected within 2 h after juice administration into the stomachs, separated from the digestive tract of a living rat. In the gastric content, betacyanins administered underwent intensive degradation and changes in their profile, as a result of the conditions prevailing in the stomach and the intensity of the absorption process. Detection of 19 betacyanins (8 native compounds and 11 metabolites) in rats' physiological fluids with the HPLC-MS/MS method proves betacyanin absorption from the stomach. In addition, the study results suggest that betacyanin dose affects the rate and extent of betacyanin degradation in the gastric content, as well as the intensity of absorption, metabolism and excretion of these pigments.