Betalain Content Research Articles

Pigment pattern and expression of colour in fruits from different Hylocereus sp. genotypes

Pigment profiles, betalain contents, colour and pH-values were studied in fruits from five Hylocereus sp. genotypes originating from Costa Rica. Significant colour differences between fruit pulps from “Nacional” and “San Ignacio” were found for C⁎-values and “Lisa” exhibited the most reddish tint h°. Whereas highest betalain contents were registered in “San Ignacio” and “Orejona”, lowest values were found in “Nacional”. Additionally, pigment patterns of the genotypes were found to differ: While “Lisa”, “Nacional” and “Orejona” were characterised by a similar betalain pattern, “Rosa” and “San Ignacio” were significantly different offering a valuable tool for genotype comparison. Moreover, “Rosa” showed the highest betanin and isobetanin contents, whereas phyllocactin and hylocerenin were predominant in “San Ignacio”. Apart from the newly reported betalains neobetanin and gomphrenin I, indicaxanthin was the first betaxanthin so far detected in pitaya fruits. Natural substitutes for synthetic colourants are increasingly gaining importance on the global market. In particular, the so-called colouring foodstuffs representing aqueous or oily plant extracts extend their market share with red-coloured preparations being particularly requested. In this regard, pitaya fruits from the genotype Hylocereus have been proposed as promising colour sources, recently. To secure the authenticity of the plant material, a reliable differentiation of pitayas from different origins is required. In addition, Hylocereus fruits may differ in their colour quality and pigment content, the knowledge of which is crucial for the selection of appropriate plants for an emerging pitaya market.

Aqueous two phase extraction for purification and concentration of betalains

As a natural food colorant, betalains are finding increased importance. The presence of free sugars accelerates the degradation of betalains, hence it is desirable to separate the sugars from the beet extract. Aqueous two-phase extraction was employed for the first time as an attractive alternative for the downstream processing of betalains, mainly for the removal of sugars without the need of additional steps. The effect of different parameters such as tie line length, phase volume ratio, concentration of phase forming components on the partitioning behavior of betalains was studied. The differential partitioning of betalains and sugars was achieved in aqueous two phase extraction at higher tie line length (34%), wherein betalains (about 70–75%) and sugars (about >90%) are partitioned in the top and bottom phases, respectively. Further, the betalains was successfully separated from the polymer employing organic–aqueous extraction resulting in 3.4 fold increase in concentration.

Colour studies on fruit juice blends from Opuntia and Hylocereus cacti and betalain-containing model solutions derived therefrom

The visual appearance and pigment stability of fruit juice blends from Opuntia and Hylocereus cacti and of betalain-containing model solutions derived therefrom were investigated at pH values ranging from 3 to 7. All samples were found to be stable as indicated by betalain contents as well as hue and chroma values over the complete pH range monitored. Both the juice and the purified betaxanthin solution from Opuntia ficus-indica cv. ‘Gialla’ were characterised by yellowish hues, while the juice and the purified betacyanin solution from Hylocereus polyrhizus displayed purplish tonalities. By blending the betaxanthin and betacyanin stock solutions, tailor-made hues covering the entire spectrum from bright yellow ( h° = 84) to purplish-blue ( h° = 333) were successfully produced. Since mixtures from purified betalains did not provide colour shades different from those obtained with raw cactus fruit juices, the use of the latter should be preferred both because of consumer-friendly labelling and improved pigment stability.

Pigment Distribution and Total Dissolved Solids of Selected Cycles of Table Beet from a Recurrent Selection Program for Increased Pigment

Half-sib recurrent selection programs were initiated at the University of Wisconsin-Madison in 1978 and 1995 to increase betalain (betacyanin and betaxanthin) concentration in red and yellow table beets (Beta vulgaris L. ssp. vulgaris), respectively. Cycles of selection from both the red and yellow table beet breeding programs were evaluated for pigment and total dissolved solids (TDS) distribution in five tissue sections (outer, middle and center zones of the root; leaf and petiole) in two environments (early and late planting) during 2002. Betaxanthin concentration increased with the later planting date in the majority of the tissue zones in the yellow and red table beet populations. Absolute pigment concentration of the outer root zone increased the most over cycles of selection: 46.6 mg/100 g fresh weight (FW) betaxanthin and 201 mg/100 g FW betacyanin for yellow and red populations, respectively. However, the greatest rate of gain was in the center and middle tissue zones. Selection based on the outer 2 cm of root tissue has effectively increased pigmentation of the entire beet plant. A correlated response to selection in leaf and petiole tissue was measured for pigment concentration in both populations. The contribution of each tissue zone to total pigment concentration of the beet plant remained constant throughout cycles of selection averaging 39%, 25%, 25%, 6%, and 5% for outer, middle, center, petiole and leaf tissue zones, respectively. Across all table beet populations, pigment concentration of the outer root zone was 55% and 62% higher than middle and center zones, respectively. TDS of the outer root zone was 10% and 12% higher than middle and center zones, respectively.

Color, Betalain Pattern, and Antioxidant Properties of Cactus Pear (Opuntiaspp.) Clones

Total phenolics, ascorbic acid, and betalain contents of differently colored cactus pear clones (nine Opuntia ficus-indica [L.] Mill. clones and one O. robusta Wendl. clone) were investigated and related to their respective antioxidant potential assessed by Trolox-equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity (ORAC) assays. TEAC and ORAC values were very highly correlated with each other and also with values for total phenolics, betalain contents, and ascorbic acid concentrations. Total phenolics had the greatest contribution to ORAC and TEAC values. High-performance liquid chromatography (HPLC)-diode array detector (DAD)-tandem mass spectrometry (MS/MS) measurements of cactus pear juices permitted the differentiation of the clones based on variations in pigment patterns and betalain concentrations. The red and yellow betalains were absent in lime green colored cactus fruits. The ratio and concentration of these pigments were responsible for the yellow, orange, red, and purple colors in the other clones. Progeny of purple and lime green colored parents were characterized by 12% and 88% of plants bearing lime green and purple fruit, respectively. This implies that the genes for betalain production were lacking in the lime green fruits but could be provided by a parent with a complete set of genes, that is, purple fruits. Besides known pigments typical of Cactaceae, two unexpected betalains were identified. Whereas gomphrenin I was found for the first time in tissues of cactus plants, methionine-betaxanthin has never been described before as a genuine betalain. In addition to their alleged health-promoting properties, various combinations of yellow betaxanthins and red-purple betacyanins may allow the development of new food products without using artificial colorants.

Betacyanins and phenolic compounds from Amaranthus spinosus L. and Boerhavia erecta L.

Stem bark extracts of Boerhavia erecta L. (erect spiderling) and Amaranthus spinosus L. (spiny amaranth), two wild growing weed plants used in traditional African medicine, were characterized with respect to their phenolic profile including the betalains. While the main betalains in A. spinosus were identified as amaranthine and isoamaranthine, the major betacyanins in B. erecta were betanin, isobetanin together with neobetanin. The latter showed higher betalain concentrations amounting to 186 mg/100 g, while the former contained 24 mg betacyanins in 100 g of the ground plant material. Extracts of A. spinosus were found to contain hydroxycinnamates, quercetin and kaempferol glycosides, whereas catechins, procyanidins and quercetin, kaempferol and isorhamnetin glycosides were detected in B. erecta. The amounts of these compounds ranged from 305 mg/100 g for A. spinosus to 329 mg/100 g for B. erecta.

Selection of LAB strains for fermented red beet juice production

Authentic LAB strains were investigated for their lactic acid, H2O2, and biogenic amine production, and their effect on red beet betalains. There was no significant difference between the strains in respect of cell propagation in beet juice. Lb. curvatus 2770 provided the best pH drop. None of the investigated LAB excreted either histamine or tyramine, but in the spontaneously fermented juice both amines were present and the total amine level was high. H2O2 synthesis was similar and not higher than 1 mg l−1. The betalain content showed greatest reduction in the case of spontaneous fermentation and similar values for the LAB strains.

Variation in betalain content and factors affecting the biosynthesis in Portulaca sp. 'Jewel' cell cultures.

Sixteen colored cell lines of Portulaca sp. ‘Jewel’ forming betalain were established, seven cultured on modified Murashige and Skoog (mMS) medium and nine on modified Girod and Zryd (mJ1). Each line was different in term of betalain content. Both betacyanin and betaxanthin widely varied in quality and quantity from line to line. A magenta-colored phenotype contained the maximum betacyanin and an orange-colored phenotype contained the maximum betaxanthin. Modified MS medium was optimal for betacyanin synthesis whereas modified J1 medium synthesized more betaxanthin. Betacyanin and betaxanthin both accumulated in a positive correlation to the cell growth in our culture system, and the highest contents were recorded during the logarithmic phase. The addition of natural auxin, indole-3-acetic acid (IAA), to both types of culture media instead of synthetic auxin, 2, 4-dichloro-phenoxyacetic acid (2, 4-D) inhibited the growth and reduced betalain synthesis. But a few subcultures after transfer to IAA-containing medium, two cell lines were established one producing betacyanin and one betaxanthin. Different cell phenotypes (either magenta or yellow colored cells) exhibit same responses in their requirement of light. Cellular betacyanin and betaxanthin drastically increased under continuous illumination, particularly with blue light irradiation along with the increasing number of growth cycles.

Induction of Betacyanin Synthesis and Pigment Accumulation in Cell Suspension Cultures of Portulaca.

The establishment of betalain-producing cell suspension cultures in Portulaca is reported for the first time. Addition of ascorbic acid (AsA) and sufficient osmotica to the culture medium was critical to the success. Betacyanin production was best at 1×103mgl-1 AsA. Small cell aggregates, formed in MS-AsA medium supplemented with 150mM mannitol and 150mM sorbitol, accumulated the highest relative amounts of betacyanins. The growth rate of cell suspension cultures increased 3- to 4- fold within 14 days in modified MS-AsA medium supplemented with 5μM 2, 4-D. The betalain content of suspended cells increased during the first 2 day in liquid culture, thereafter decreased slightly and increased again during the logarithmic phase of cellular growth. A lower concentration of 2, 4-D inhibited the growth of cultures but did not significantly affect betacyanin accumulation. Addition of cytokinin inhibited growth and also resulted in decreased betacyanin accumulation. The pigmentation of cultured cells decolourized upon transfer to dark conditions but was regained in decolourized cells at 12 to 24 hours after light exposure. The levels of endogenous free tyrosine and DOPA, precursors of betalains, decreased in response to light and slightly increased again after 24 hours of light treatment. Betanin, the main pigment component, as well as other betacyanins present, dramatically increased after 24 hours under light conditions in our Portulaca cell suspension culture system.

039 The Blotchy Gene, bl, is Linked to the R and Y Loci in Table Beet

The primary pigments in red beet are the betalains, which are comprised of the red-violet betacyanins and the yellow betaxanthins. Modification of betalain content and distribution in table beet has been practiced by breeders for many years, although little is known about the genetic control of these traits. The presence of dominant alleles at two linked loci (R and Y) condition production of betalain pigment in the beet plant. Red-pigmented roots are observed only in the presence of dominant alleles at the R and Y loci, while white roots are conditioned by recessive alleles at both loci and yellow roots by the genotype rrY-. A newly described gene, `blotchy' (bl), conditions a blotchy or irregular pigment patterning in either red or yellow roots. The objective of this investigation was to characterize the linkage relationships between the R and Y loci and the bl gene by evaluating segregating progenies developed from a series of matings of colored and white table beets. Segregation data indicate the bl gene is independent from R and Y and that this locus is linked to R and Y. The two-point linkage estimate between the R and Y loci pooled over eight crosses was 7.4 (1.7 cM) Linkage between R and Bl was estimated from a pooled sample of four crosses at 16.7 (10.8 cM). The most likely gene order was R-Y-Bl. These data suggest the RYBl genomic region plays a critical role in the genetic control of betalain biosynthesis in table beet.

Estabilidad de las betalaínas extraídas del garambullo (Myrtillocactus geometrizans) / Stability of betalains extracted from garambullo (Myrtillocactus geometrizans)

The garambullo is a cactus that grows in arid and semiarid zones; it bears a purple fruit which contains pigments belonging to the betalain family. Several extractions of the pigment were performed using different solvents and its stability was evaluated in the presence of stabilizing agents. The major concentration of betalains was extracted with ethanol-HCl (99:1); however, these pigments were more unstable (ΔE = 14.6) as compared with the pigment obtained by an aqueous extraction (ΔE = 12.3). The results showed that the pigment is stable at pH 4.8-5.2 and low temper atures, this was confirmed by the half-life: at 25 °C the half-life was 11 413.6 min in comparison with 83.5 min at 60 °C. In the presence of 0.1% ascorbic acid the half-life was doubled and the energy of activation was 25.78 kcal/mol compared to 22.07 kcal/mol for the control. Ascorbic acid 0.1% was the best stabilizing agent among the compounds used in the present study of Myrtillocactus geometrizans pigment in aqueous solution at pH 4.8 and 5.2.

Growth and productivity of Beta vulgaris cell culture in fluidized bed reactors

Beta vulgaris cells were cultured in specially constructed fluidized bed reactors on Murashige and Skoog medium with 3% sucrose as a carbon source. Biomass density levels of approximately 17–18 g dry cell weight liter−1 for 5 liter fermenters and 9–10 g dry cell weight liter−1 for 50 liter reactor were observed. Depending on particular cell line, cell content of betalains reached levels ranging from 12 to 25 mg g dry cell weight−1, representing the productivities of 14 to 17 mg of pigments per liter and day.

Patent invention

Physical features, bioactive compounds and total antioxidant capacity (TAC) of coloured quinoa varieties (Chenopodium quinoa Willd.) from Peruvian Altiplano were studied. Quinoa seeds did not show a pure red colour, but a mixture which corresponded to different fractal colour values (51.0–71.8), and they varied from small to large size. Regarding bioactive compounds, total phenolic (1.23–3.24 mg gallic acid equivalents/g) and flavonol contents (0.47–2.55 mg quercetin equivalents/g) were highly correlated (r = 0.910). Betalains content (0.15–6.10 mg/100 g) was correlated with L colour parameter (r = −0.569), total phenolics (r = 0.703) and flavonols content (r = 0.718). Ratio of betaxanthins to betacyanins (0.0–1.41) was negatively correlated with L value (r = −0.744). Whereas, high TAC values (119.8–335.9 mmol Trolox equivalents/kg) were negatively correlated with L value (r = −0.779), but positively with betalains (r = 0.730), as well as with free (r = 0.639), bound (r = 0.558) and total phenolic compounds (r = 0.676). Unexploited coloured quinoa seeds are proposed as a valuable natural source of phenolics and betalains with high antioxidant capacity.