Extraction and Stabilization of Betalains from Beetroot (Beta vulgaris) Wastes Using Deep Eutectic Solvents.

Deep eutectic solvents (DES) using magnesium chloride hexahydrate [MgCl2·6H2O] and urea [U] proportions (1:1) and (2:1), were prepared for their use as extracting and stabilizer agents for red and violet betalains from beetroot (Beta vulgaris) waste. The synthetized DES [MgCl2·6H2O] [U] showed similar properties to eutectic mixtures, such as, liquid phase, low melting points and conductivity, thermal stability, and variable viscosity. In turn, betalain DES extracts (2:1) exhibited compatibility in the extraction and recovery of betalains from beetroot wastes, showing a betalain content comparable to that of betalain extracts. Betalain stability was determined by degradation tests; the exposure conditions were visible light (12 h), molecular oxygen from atmospheric air and environmental temperature (20-27 °C) for 40 days. The kinetic curves of the betalain degradation of water samples depicted a first-order model, indicating the alteration of a violet colouration of betalains from beetroot waste for 5-7 days. However, betalains from DES extracts were kept under visible light for 150 days, and for 340 days in storage (amber vessels), achieving a stability of 75% in comparison with initial beet extracts.

Clarification Processes of Orange Prickly Pear Juice (Opuntia spp.) by Microfiltration.

In this study, fresh orange prickly pear juice (Opuntia spp.) was clarified by a cross-flow microfiltration (MF) process on a laboratory scale. The viability of the process-in terms of productivity (permeate flux of 77.80 L/h) and the rejection of selected membranes towards specific compounds-was analyzed. The quality of the clarified juice was also analyzed for total antioxidants (TEAC), betalains content (mg/100 g wet base), turbidity (NTU) and colorimetry parameters (L, a*, b*, Croma and H). The MF process permitted an excellent level of clarification, reducing the suspended solids and turbidity of the fresh juice. In the clarified juice, a decrease in total antioxidants (2.03 TEAC) and betalains content (4.54 mg/100 g wet basis) was observed as compared to the fresh juice. Furthermore, there were significant changes in color properties due to the effects of the L, a*, b*, C and h° values after removal of turbidity of the juice. The turbidity also decreased (from 164.33 to 0.37 NTU).

A bioinspired nitrone precursor to a stabilized nitroxide radical.

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

Natural colorants improved the physicochemical and sensorial properties of frozen Brazilian sausage (linguiça) with reduced nitrite

The use of natural colorants in meat products can keep its coloring attractive as well as meet the demand from consumers interested in products that are healthier. Nitrite is added as a preservative to these products and it is also a precursor of the generation of a specifically desired color in meat products. However, its use has been associated with the development of certain kinds of cancer. The objective of this study was to evaluate the effect of reduced levels of nitrite in Brazilian sausage (linguiça) with natural colorants on the physicochemical and sensorial properties following frozen storage. Nine treatments were tested: 0.015 % nitrite (C150), 0.0075 % nitrite (C75) and 0 % nitrite (C0), 0.0075 % nitrite and 1.5 % microencapsulated betalain (BME75), 0 % nitrite and 1.5 % microencapsulated betalain (BME0), 0.0075 % nitrite and 0.19 % commercial betalain (BCP75), 0 % nitrite and 0.19 % commercial betalain (BCP0), 0.0075 % nitrite and 0.02 % of cochineal carmine (CC75) and 0 % nitrite and 0.02 % of cochineal carmine (CC0). Oxidative stability, residual nitrite and instrumental color were the determinant factors. Sensory analysis was directed at color, texture, taste and global acceptance. Natural colorants did not have any antioxidant effect. Sausages prepared with betalain and 0.0075 % nitrite showed the highest a* values. The addition of colorants improved both color and overall acceptance. The addition of betalain and cochineal carmine with 0.0075 % nitrite proved to be effective in achieving high acceptability in Brazilian sausage (linguiça).

Natural colorants improved the physicochemical and sensorial properties of frozen Brazilian sausage (linguiça) with reduced nitrite

The use of natural colorants in meat products can keep its coloring attractive as well as meet the demand from consumers interested in products that are healthier. Nitrite is added as a preservative to these products and it is also a precursor of the generation of a specifically desired color in meat products. However, its use has been associated with the development of certain kinds of cancer. The objective of this study was to evaluate the effect of reduced levels of nitrite in Brazilian sausage (linguiça) with natural colorants on the physicochemical and sensorial properties following frozen storage. Nine treatments were tested: 0.015 % nitrite (C150), 0.0075 % nitrite (C75) and 0 % nitrite (C0), 0.0075 % nitrite and 1.5 % microencapsulated betalain (BME75), 0 % nitrite and 1.5 % microencapsulated betalain (BME0), 0.0075 % nitrite and 0.19 % commercial betalain (BCP75), 0 % nitrite and 0.19 % commercial betalain (BCP0), 0.0075 % nitrite and 0.02 % of cochineal carmine (CC75) and 0 % nitrite and 0.02 % of cochineal carmine (CC0). Oxidative stability, residual nitrite and instrumental color were the determinant factors. Sensory analysis was directed at color, texture, taste and global acceptance. Natural colorants did not have any antioxidant effect. Sausages prepared with betalain and 0.0075 % nitrite showed the highest a* values. The addition of colorants improved both color and overall acceptance. The addition of betalain and cochineal carmine with 0.0075 % nitrite proved to be effective in achieving high acceptability in Brazilian sausage (linguiça).(AU)

Rationale on the High Radical Scavenging Capacity of Betalains.

Betalains are water-soluble natural pigments of increasing importance as antioxidants for pharmaceutical use. Although non-phenolic betalains have lower capacity to scavenge radicals compared to their phenolic analogues, both classes perform well as antioxidants and anti-inflammatory agents in vivo. Here we show that meta-hydroxyphenyl betalain (m-OH-pBeet) and phenylbetalain (pBeet) show higher radical scavenging capacity compared to their N-methyl iminium analogues, in which proton-coupled electron transfer (PCET) from the imine nitrogen atom is precluded. The 1,7-diazaheptamethinium system was found to be essential for the high radical scavenging capacity of betalains and concerted PCET is the most thermodynamically favorable pathway for their one-electron oxidation. The results provide useful insights for the design of nature-derived redox mediators based on the betalain scaffold.

Microencapsulation of betanin in monodisperse W/O/W emulsions.

Betanin is the main pigment of the food color beetroot red (E162). Due to the fair heat and light stability of E162, this pigment is mainly used in minimally processed packaged food products. Encapsulation increases the stability of betanin, but detailing on the effect of different sources of betanin on the properties and stability of multiple emulsions are scarce. Here we describe the encapsulation of E162, spray-dried beetroot juice and betanin in a monodisperse food-grade water-in-oil-in-water (W/O/W) emulsions by using microchannel emulsification. We compare the tinctorial strength of the encapsulated pigments and investigate the effect of temperature, storage period and pigment concentration on emulsion stability and color. Betanin increases the overall stability of the W/O/W emulsion, reduce the oil droplet size and improve size distribution when compared to the negative control without pigment and to emulsions containing betanin from other sources.

Production of pigments in Alternanthera sessilis calli mediated by plant growth regulators and light / Produção de pigmentos em calos de Alternanthera sessilis mediados por reguladores de crescimento e luz

Among the compounds produced by plants, pigments such as betalains have received attention from both food and pharmaceuticals industries. The Alternanthera sessilis species produces these pigments, though in small quantities, and so it is necessary to increase production. Thus, many studies use elicitors that are capable of triggering physiological or morphological responses in plants. The objective was to establish callus production in A. sessilis grown under different combinations of growth regulators and light qualities and to assess whether these factors can increase betalain and flavonoid production. Leaf and internodal explants in MS medium with different growth regulators were used to obtain calli, which were subsequently transferred to a betacyanin induction medium remaining for 40 days under different light qualities (white, blue, red, and dark). The most suitable treatment for callus formation and subsequent betalain and flavonoid induction was to combine a medium containing 6.7 µmol L-1 2,4-D and 9.0 µmol L-1 BAP and blue light. Physical elicitation by light combined with appropriate concentration of growth regulators on calli can increase production of commercially important metabolites.(AU) 

Dentre os compostos produzidos pelas plantas, os pigmentos, como as betalaínas, vêm recebendo destaque tanto pela indústria alimentícia como farmacêutica. A espécie Alternanthera sessilis produz esses pigmentos, porém em pequenas quantidades, sendo necessário incrementar a produção. Para isso, muitos estudos utilizam elicitores que são capazes de desencadear respostas fisiológicas ou morfológicas nas plantas. O objetivo do trabalho foi estabelecer a produção de calos de A. sessilis crescidos quando submetidos a diferentes combinações de reguladores de crescimento e qualidades de luz, e avaliar se esses fatores são capazes de incrementar a produção de betalaínas e flavonoides. Foram utilizados explantes foliares e internodais em meio MS com diferentes reguladores de crescimento para obtenção dos calos que, posteriormente, foram transferidos para meio de indução de betacianina, onde permaneceram por 30 dias sob diferentes qualidades de luz (branca, azul, vermelha e escuro). O tratamento mais propício para formação de calos e consequente indução de betalaínas e flavonoides foi a combinação do meio contendo 6,7 μmol L-1 2,4-D e 9,0 μmol L-1 BAP e a luz azul. Conclui-se que a elicitação física pela luz em conjunto com a concentração adequada de reguladores de crescimento em calos é capaz de incrementar a produção de metabólitos de interesse comercial.(AU)

Production of pigments in Alternanthera sessilis calli mediated by plant growth regulators and light / Produção de pigmentos em calos de Alternanthera sessilis mediados por reguladores de crescimento e luz

Among the compounds produced by plants, pigments such as betalains have received attention from both food and pharmaceuticals industries. The Alternanthera sessilis species produces these pigments, though in small quantities, and so it is necessary to increase production. Thus, many studies use elicitors that are capable of triggering physiological or morphological responses in plants. The objective was to establish callus production in A. sessilis grown under different combinations of growth regulators and light qualities and to assess whether these factors can increase betalain and flavonoid production. Leaf and internodal explants in MS medium with different growth regulators were used to obtain calli, which were subsequently transferred to a betacyanin induction medium remaining for 40 days under different light qualities (white, blue, red, and dark). The most suitable treatment for callus formation and subsequent betalain and flavonoid induction was to combine a medium containing 6.7 µmol L-1 2,4-D and 9.0 µmol L-1 BAP and blue light. Physical elicitation by light combined with appropriate concentration of growth regulators on calli can increase production of commercially important metabolites.

Dentre os compostos produzidos pelas plantas, os pigmentos, como as betalaínas, vêm recebendo destaque tanto pela indústria alimentícia como farmacêutica. A espécie Alternanthera sessilis produz esses pigmentos, porém em pequenas quantidades, sendo necessário incrementar a produção. Para isso, muitos estudos utilizam elicitores que são capazes de desencadear respostas fisiológicas ou morfológicas nas plantas. O objetivo do trabalho foi estabelecer a produção de calos de A. sessilis crescidos quando submetidos a diferentes combinações de reguladores de crescimento e qualidades de luz, e avaliar se esses fatores são capazes de incrementar a produção de betalaínas e flavonoides. Foram utilizados explantes foliares e internodais em meio MS com diferentes reguladores de crescimento para obtenção dos calos que, posteriormente, foram transferidos para meio de indução de betacianina, onde permaneceram por 30 dias sob diferentes qualidades de luz (branca, azul, vermelha e escuro). O tratamento mais propício para formação de calos e consequente indução de betalaínas e flavonoides foi a combinação do meio contendo 6,7 µmol L-1 2,4-D e 9,0 µmol L-1 BAP e a luz azul. Conclui-se que a elicitação física pela luz em conjunto com a concentração adequada de reguladores de crescimento em calos é capaz de incrementar a produção de metabólitos de interesse comercial.

Microencapsulation of betalains obtained from cactus fruit (Opuntia ficus-indica) by spray drying using cactus cladode mucilage and maltodextrin as encapsulating agents.

The microencapsulation of betalains from cactus fruit by spray drying was evaluated as a stabilization strategy for these pigments. The betalains used as active agent were extracted from purple fruits of Opuntia ficus-indica (BE) and encapsulated with maltodextrin and cladode mucilage MD-CM and only with MD. The microcapsulates were characterized by scanning electron microscopy (SEM), thermal analysis (TGA-DSC), tristimulus colorimetry, as well as, their humidity, water activity and dietary fiber content were also determined. The active agent content was measured by UV-Vis spectrophotometry and its composition confirmed by HPLC-ESIMS. A pigment storage stability test was performed at 18 °C and different relative humidities. The addition of CM in the formulation increased the encapsulation efficiency, diminished the moisture content, and allowed to obtain more uniform size and spherical particles, with high dietary fiber content. These microencapsulates are promising functional additive to be used as natural colorant in the food industry.

Produção de betacianina em erva-de-jacaré cultivada in vitro com diferentes concentrações de sulfato de cobre / Betacyanin production in alligator weed, grown in vitro, with different concentrations of copper sulfate

A manipulação da concentração dos microelementos no meio de cultura representa uma boa estratégia para aumentar a produção de metabólitos secundários em cultura de tecidos. Este trabalho teve por objetivo demonstrar a influência do sulfato de cobre na produção de betacianina e na multiplicação de plantas de Alternanthera philoxeroides (erva-de-jacaré) cultivadas in vitro. Segmentos nodais, obtidos de plantas pré-estabelecidas e após três subcultivos, foram inoculados em meio MS, com diferentes concentrações de CuSO4 (0; 25; 75; 125; 175; 200µM). O delineamento experimental utilizado foi inteiramente casualizado, com seis concentrações de CuSO4 e cinco repetições representadas por um frasco contendo quatro explantes. Os resultados foram submetidos à análise de variância, à regressão polinomial e a análises de correlação entre as variáveis morfológicas e a produção de betacianina. Concentrações acima de 75µM diminuíram a altura das plantas, o número de brotos e gemas e o crescimento radicular, enquanto que, na concentração de 125µM, houve a maior produção de massa fresca. A produção de betacianina aumentou 60 por cento em relação ao controle com 175µM de CuSO4. Ocorreu crescimento das plantas em todas as concentrações de CuSO4 testadas, com exceção de 200µM, sendo esta considerada tóxica.

The manipulation of concentration of trace elements in the culture medium represents a good strategy to increase the production of secondary metabolites in tissue culture. This study aimed to demonstrate the influence of copper sulphate in the production of betacyanin and the multiplication of plants of Alternanthera philoxeroides (alligator weed) cultured in vitro. Nodal segments, obtained from plants pre-stablished and after three subcultures, were inoculated in basic MS with different concentrations of CuSO4 (0, 25, 75, 125, 175, 200µM). The results were subjected to analysis of variance, polynomial regression and correlation analysis between the morphological variables and the production of betacyanin. The experimental design was completely randomized with six concentration of CuSO4 and five replicates represented by a bottle containing four explants. Concentrations above 75µM decreased the height of the plant, number of shoots and buds and root growth, while the concentration of 125µM resulted in the highest fresh mass production. Betacyanin production increased 60 percent over control with 175µM CuSO4. Plant growth occurred in all tested concentrations of CuSO4, with the exception of 200µM which was toxic.

Produção de betacianina em erva-de-jacaré cultivada in vitro com diferentes concentrações de sulfato de cobre

The manipulation of concentration of trace elements in the culture medium represents a good strategy to increase the production of secondary metabolites in tissue culture. This study aimed to demonstrate the influence of copper sulphate in the production of betacyanin and the multiplication of plants of Alternanthera philoxeroides (alligator weed) cultured in vitro. Nodal segments, obtained from plants pre-stablished and after three subcultures, were inoculated in basic MS with different concentrations of CuSO4 (0, 25, 75, 125, 175, 200µM). The results were subjected to analysis of variance, polynomial regression and correlation analysis between the morphological variables and the production of betacyanin. The experimental design was completely randomized with six concentration of CuSO4 and five replicates represented by a bottle containing four explants. Concentrations above 75µM decreased the height of the plant, number of shoots and buds and root growth, while the concentration of 125µM resulted in the highest fresh mass production. Betacyanin production increased 60% over control with 175µM CuSO4. Plant growth occurred in all tested concentrations of CuSO4, with the exception of 200µM which was toxic.

A manipulação da concentração dos microelementos no meio de cultura representa uma boa estratégia para aumentar a produção de metabólitos secundários em cultura de tecidos. Este trabalho teve por objetivo demonstrar a influência do sulfato de cobre na produção de betacianina e na multiplicação de plantas de Alternanthera philoxeroides (erva-de-jacaré) cultivadas in vitro. Segmentos nodais, obtidos de plantas pré-estabelecidas e após três subcultivos, foram inoculados em meio MS, com diferentes concentrações de CuSO4 (0; 25; 75; 125; 175; 200µM). O delineamento experimental utilizado foi inteiramente casualizado, com seis concentrações de CuSO4 e cinco repetições representadas por um frasco contendo quatro explantes. Os resultados foram submetidos à análise de variância, à regressão polinomial e a análises de correlação entre as variáveis morfológicas e a produção de betacianina. Concentrações acima de 75µM diminuíram a altura das plantas, o número de brotos e gemas e o crescimento radicular, enquanto que, na concentração de 125µM, houve a maior produção de massa fresca. A produção de betacianina aumentou 60% em relação ao controle com 175µM de CuSO4. Ocorreu crescimento das plantas em todas as concentrações de CuSO4 testadas, com exceção de 200µM, sendo esta considerada tóxica.

Produção de betacianina em erva-de-jacaré cultivada in vitro com diferentes concentrações de sulfato de cobre

The manipulation of concentration of trace elements in the culture medium represents a good strategy to increase the production of secondary metabolites in tissue culture. This study aimed to demonstrate the influence of copper sulphate in the production of betacyanin and the multiplication of plants of Alternanthera philoxeroides (alligator weed) cultured in vitro. Nodal segments, obtained from plants pre-stablished and after three subcultures, were inoculated in basic MS with different concentrations of CuSO4 (0, 25, 75, 125, 175, 200µM). The results were subjected to analysis of variance, polynomial regression and correlation analysis between the morphological variables and the production of betacyanin. The experimental design was completely randomized with six concentration of CuSO4 and five replicates represented by a bottle containing four explants. Concentrations above 75µM decreased the height of the plant, number of shoots and buds and root growth, while the concentration of 125µM resulted in the highest fresh mass production. Betacyanin production increased 60% over control with 175µM CuSO4. Plant growth occurred in all tested concentrations of CuSO4, with the exception of 200µM which was toxic.

A manipulação da concentração dos microelementos no meio de cultura representa uma boa estratégia para aumentar a produção de metabólitos secundários em cultura de tecidos. Este trabalho teve por objetivo demonstrar a influência do sulfato de cobre na produção de betacianina e na multiplicação de plantas de Alternanthera philoxeroides (erva-de-jacaré) cultivadas in vitro. Segmentos nodais, obtidos de plantas pré-estabelecidas e após três subcultivos, foram inoculados em meio MS, com diferentes concentrações de CuSO4 (0; 25; 75; 125; 175; 200µM). O delineamento experimental utilizado foi inteiramente casualizado, com seis concentrações de CuSO4 e cinco repetições representadas por um frasco contendo quatro explantes. Os resultados foram submetidos à análise de variância, à regressão polinomial e a análises de correlação entre as variáveis morfológicas e a produção de betacianina. Concentrações acima de 75µM diminuíram a altura das plantas, o número de brotos e gemas e o crescimento radicular, enquanto que, na concentração de 125µM, houve a maior produção de massa fresca. A produção de betacianina aumentou 60% em relação ao controle com 175µM de CuSO4. Ocorreu crescimento das plantas em todas as concentrações de CuSO4 testadas, com exceção de 200µM, sendo esta considerada tóxica.

Armazenamento refrigerado de beterraba minimamente processada em diferentes tipos de corte

Fresh cut beetroot showed low shelf life, even under refrigeration, and the main quality depreciative factor is the superficial discoloration (white blush) that depreciates the quality of the product. The objective of this research was to verify the effect of three cut types on quality of the minimally processed beetroot during cold storage. The cut types used were slice, cube and shred. After processing, the beetroots were stored at 5°C during ten days and the evaluations were carried out each two days. Sliced beetroots showed higher respiratory rate and higher losses of betalains and soluble solids during cold storage. Visual quality of minimally processed beetroot was preserved up to four days of storage in both cut type. The main factor that has caused loss of quality of this vegetable was the incidence of white blush. It can be concluded that the beet minimally processed in slices or cube presents conservation of, at the most 4 days to 5°C, while minimally processed in shred it presents 6 days of conservation.

Beterrabas minimamente processadas apresentam vida de prateira curta, mesmo sob refrigeração, devido à descoloração superficial que deprecia a qualidade do produto. O objetivo do trabalho foi verificar o efeito de três tipos de corte em beterraba minimamente avaliando sua qualidade durante a conservação refrigerada. Os cortes utilizados foram: fatia, cubo e retalho. Após o processamento as beterrabas foram armazenadas a 5°C e as avaliações sendo realizadas durante dez dias a cada dois dias. Beterrabas em fatias apresentaram maior respiração e maiores perdas dos pigmentos betalaínas e de sólidos solúveis durante o armazenamento. Através de análise sensorial, verificou-se que a qualidade visual do produto foi mantida por até quatro dias, independente do tipo de corte. O fator que mais depreciou a qualidade de beterraba minimamente processada foi a perda de coloração das raízes (esbranquiçamento). Pode-se concluir que a beterraba minimamente processada em fatias ou cubo apresenta conservação de, no máximo 4 dias, a 5°C, enquanto minimamente processada em retalho apresenta 6 dias de conservação.

Armazenamento refrigerado de beterraba minimamente processada em diferentes tipos de corte

Fresh cut beetroot showed low shelf life, even under refrigeration, and the main quality depreciative factor is the superficial discoloration (white blush) that depreciates the quality of the product. The objective of this research was to verify the effect of three cut types on quality of the minimally processed beetroot during cold storage. The cut types used were slice, cube and shred. After processing, the beetroots were stored at 5°C during ten days and the evaluations were carried out each two days. Sliced beetroots showed higher respiratory rate and higher losses of betalains and soluble solids during cold storage. Visual quality of minimally processed beetroot was preserved up to four days of storage in both cut type. The main factor that has caused loss of quality of this vegetable was the incidence of white blush. It can be concluded that the beet minimally processed in slices or cube presents conservation of, at the most 4 days to 5°C, while minimally processed in shred it presents 6 days of conservation.

Beterrabas minimamente processadas apresentam vida de prateira curta, mesmo sob refrigeração, devido à descoloração superficial que deprecia a qualidade do produto. O objetivo do trabalho foi verificar o efeito de três tipos de corte em beterraba minimamente avaliando sua qualidade durante a conservação refrigerada. Os cortes utilizados foram: fatia, cubo e retalho. Após o processamento as beterrabas foram armazenadas a 5°C e as avaliações sendo realizadas durante dez dias a cada dois dias. Beterrabas em fatias apresentaram maior respiração e maiores perdas dos pigmentos betalaínas e de sólidos solúveis durante o armazenamento. Através de análise sensorial, verificou-se que a qualidade visual do produto foi mantida por até quatro dias, independente do tipo de corte. O fator que mais depreciou a qualidade de beterraba minimamente processada foi a perda de coloração das raízes (esbranquiçamento). Pode-se concluir que a beterraba minimamente processada em fatias ou cubo apresenta conservação de, no máximo 4 dias, a 5°C, enquanto minimamente processada em retalho apresenta 6 dias de conservação.