Volatile, Microbial, and Sensory Profiles and Consumer Acceptance of Coffee Cascara Kombuchas.

Given the substantial world coffee production, tons of coffee fruit cascara rich in bioactive compounds are discarded annually. Using this by-product to produce potentially healthy and acceptable foods is a sustainable practice that aggregates value to coffee production and may help improve people's lives. This study aimed to elaborate kombuchas from coffee cascara tea, evaluate their microbial profile, and monitor the changes in the volatile profile during fermentation, together with sensory attributes and acceptance by consumers from Rio de Janeiro (n = 113). Arabica coffee cascaras from Brazil and Nicaragua were used to make infusions, to which black tea kombucha, a Symbiotic Culture of Bacteria and Yeasts (SCOBY), and sucrose were added. Fermentation of plain black tea kombucha was also monitored for comparison. The volatile profile was analyzed after 0, 3, 6, and 9 days of fermentation via headspace solid phase microextraction GC-MS. A total of 81 compounds were identified considering all beverages, 59 in coffee cascara kombuchas and 59 in the black tea kombucha, with 37 common compounds for both. An increase mainly in acids and esters occurred during fermentation. Despite the similarity to black tea kombucha, some aldehydes, esters, alcohols, and ketones in coffee cascara kombucha were not identified in black tea kombucha. Potential impact compounds in CC were linalool, decanal, nonanal, octanal, dodecanal, ethanol, 2-ethylhexanol, ethyl acetate, ethyl butyrate, ethyl acetate, ß-damascenone, γ-nonalactone, linalool oxide, phenylethyl alcohol, geranyl acetone, phenylacetaldehyde, isoamyl alcohol, acetic acid, octanoic acid, isovaleric acid, ethyl isobutyrate, ethyl hexanoate, and limonene. The mean acceptance scores for cascara kombuchas varied between 5.7 ± 0.53 and 7.4 ± 0.53 on a nine-point hedonic scale, with coffee cascara from three-day Nicaragua kombucha showing the highest score, associated with sweetness and berry, honey, woody, and herbal aromas and flavors. The present results indicate that coffee cascara is a promising by-product for elaboration of fermented beverages, exhibiting exotic and singular fingerprinting that can be explored for applications in the food industry.

Black Tea Extracts/Polyvinyl Alcohol Active Nanofibers Electrospun Mats with Sustained Release of Polyphenols for Food Packaging Applications.

The efficiency in the capabilities to store and release antioxidants depends on the film morphology and its manufacturing process, as well as on the type and methodology used to obtain the polyphenol extracts. Here, hydroalcoholic extracts of black tea polyphenols (BT) were obtained and dropped onto different polyvinyl alcohol (PVA) aqueous solutions (water or BT aqueous extract with and without citric acid, CA) to obtain three unusual PVA electrospun mats containing polyphenol nanoparticles within their nanofibers. It was shown that the mat obtained through the nanoparticles precipitated in BT aqueous extract PVA solution presented the highest total polyphenol content and antioxidant activity, and that the addition of CA as an esterifier or PVA crosslinker interfered with the polyphenols. The release kinetics in different food simulants (hydrophilic, lipophilic and acidic) were fitted using Fick's diffusion law and Peppas' and Weibull's models, showing that polymer chain relaxation is the main mechanism in all food simulants except for the acidic, which presented an abrupt release by Fick's diffusion mechanism of about 60% before being controlled. This research provides a strategy for the development of promising controlled-release materials for active food packaging, mainly for hydrophilic and acidic food products.

Kombucha: A review of substrates, regulations, composition, and biological properties.

Kombucha has been gaining prominence around the world and becoming popular due to its good health benefits. This beverage is historically obtained by the tea fermentation of Camellia sinensis and by a biofilm of cellulose containing the symbiotic culture of bacteria and yeast (SCOBY). The other substrates added to the C. sinensis tea have also been reported to help kombucha production. The type as well as the amount of sugar substrate, which is the origin of SCOBY, in addition to time and temperature of fermentation influence the content of organic acids, vitamins, total phenolics, and alcoholic content of kombucha. The route involved in the metabolite biotransformation identified in kombucha so far and the microorganisms involved in the process need to be further studied. Some nutritional properties and benefits related to the beverage have already been reported. Antioxidant and antimicrobial activities and antidiabetic and anticarcinogenic effects are some of the beneficial effects attributed to kombucha. Nevertheless, scientific literature needs clinical studies to evaluate these benefits in human beings. The toxic effects associated with the consumption of kombucha are still unclear, but due to the possibility of adverse reactions occurring, its consumption is contraindicated in infants and pregnant women, children under 4-years-old, patients with kidney failure, and patients with HIV. The regulations in place for kombucha address a number of criteria, mainly for the pH and alcohol content, in order to guarantee the quality and safety of the beverage as well as to ensure transparency of information for consumers.

Effects of Breaking up Deskwork with Physical Activity Combined with Tea Consumption on Cerebrovascular Function, Mood, and Affect

Abstract Background: Prolonged sitting, typical of desk work, decreases cerebral blood flow (CBF), mood and affect. Conversely, short physical activity breaks from sitting may prevent these detrimental effects and provide cardiometabolic benefits. Objective: We evaluated the effect of interrupting prolonged sitting with short breaks of light physical activity combined with tea consumption on CBF, cerebral autoregulation (CA), mood, and affect in desk workers. Methods: Nineteen healthy desk workers (ten male, 27±10 years) performed desk work in a laboratory for six hours on two separate intervention days: tea breaks (TEA-BREAK: short walk combined with ingestion of one cup of tea every hour) and sedentary (SED: ingestion of one cup of water every hour, while seated). Before and after desk work, we assessed mean arterial pressure (MAP), middle cerebral artery blood velocity (MCAv) and CA. Questionnaires were used to assess mood (Bond & Lader, PANAS) and affect (Affect grid) before and after the intervention. Data are expressed as mean ± standard deviation. Two-way ANOVA with repeated measurements followed by Sidak post hoc test was used for data analysis. Paired Student's t-test was also used to compare changes (Δ) between trials. Statistical significance was at p<0.05. Results: Desk work increased MAP (4.6±4.6 Δ mmHg; P<0.05), and decreased MCAv (-5.2±7.0 Δ cm/s; P<0.05), with no difference between interventions in these parameters. TEA-BREAKS, but not SED, decreased gain (-0.08±0.12 Δ cm.s−1.mmHg.−1) and increased phase (5.26±8.84 Δ radians) at very low frequency (P<0.05), but not at low frequency. Small changes in positive affect were found after the six hours of desk work (-5.5±7.3 Δ scale; P<0.05), with no differences between interventions. Conclusion: Changes in MCAv and positive affect induced by prolonged desk work could not be prevented by TEA-BREAKS. However, TEA-BREAKS improved CA, suggesting a higher efficiency in maintaining MCAv in response to blood pressure fluctuations.

Comparative evaluation of antimicrobial potential of herbal extracts on Streptococcus mutans and Enterococcus faecalis An in vitro study / Avaliação comparativa do potencial antimicrobiano de extratos de ervas em Streptococcus mutans e Enterococcus faecalis: estudo in vitro

Though aloe vera extract, green tea extract and coriander oil are proven antimicrobial agents, very little information is available regarding its effects on oral bacteria, Streptococcus mutans, which is responsible for initiating caries and Enterococcus faecalis, responsible for failure of root canal treatment. Objective: To find the antimicrobial activity of aloe vera extract, black tea extract and coriander oil against S. mutans and E. faecalis. Materials and Methods: The agar well diffusion method was used to determine the antibacterial activity of Aloe vera extract, black tea extract and coriander oil. Different concentration of prepared plant extracts and coriander seed oil (50 & 100 µl) was incorporated into the wells and the plates containing S. mutans and E. faecalis were incubated at 37 °C for 24 h. The antibiotic (amoxicillin 30 µl) was used as positive control. Zone Of Inhibition (ZOI) was recorded in each plate. Results: For S. mutans, the maximum ZOI was created by coriander oil with a diameter of 25.00±0.58 mm at 50 µl and for E. faecalis, maximum ZOI was created by aloe vera extract 16.00±0.58 mm at 100 µl concentration which were far better than the control: amoxicillin 30 µl concentration. Conclusion: The extracts of Aloe vera, black tea and coriander oil, showed significant activity against the investigated microbial strains, Streptococcus mutans and Enterococcus faecalis which further helps in the development of new topical agents that help in reducing the numbers of these organisms present in the oral cavity. (AU)

Embora o extrato de aloe vera, extrato de chá verde e óleo de coentro sejam agentes antimicrobianos comprovados, há pouca informação disponível sobre seus efeitos nas bactérias orais, Streptococcus mutans, que é responsável por iniciar cáries e Enterococcus faecalis, responsável pela falha do tratamento de canal radicular. Objetivo: Avaliar a atividade antimicrobiana do extrato de aloe vera, extrato de chá preto e óleo de coentro contra S. mutans e E. faecalis. Materiais e Métodos: O método de difusão em agar foi usado para determinar a atividade antibacteriana do extrato de Aloe vera, extrato de chá preto e óleo de coentro. Diferentes concentrações dos extratos de plantas e óleo de semente de coentro (50 e 100 µl) foram preparados e colocados nos poços e nas placas contendo S. mutans e E. faecalis e foram incubadas a 37°C por 24 h. O antibiótico (amoxicilina 30 µl) foi utilizado como controle positivo. A zona de inibição (ZOI) foi registrada em cada placa. Resultados: Para S. mutans, a ZOI máxima foi obtida com o óleo de coentro com um diâmetro de 25,00 ± 0,58 mm a 50 µl e para E. faecalis, a ZOI máxima foi obtiada pelo extrato de aloe vera 16,00 ± 0,58 mm na concentração de 100 µl, as quais foram melhores do que o controle: concentração de 30 µl de amoxicilina. Conclusão: Os extratos de Aloe vera, chá preto e óleo de coentro apresentaram atividade significativa contra as cepas microbianas investigadas, Streptococcus mutans e Enterococcus faecalis auxiliando no desenvolvimento de novos agentes tópicos visando a redução do número desses organismos presentes no cavidade oral. (AU)

Effect of Black and Green Tea on Salivary pH: a Double Blinded Cross-Over Study / Efeito do Chá Preto e Verde no pH Salivar: um Estudo Duplo Cego Cross-Ove

Introdução: Alguns produtos à base de plantas podem afetar o pH salivar e a prevenção da cárie dentária. O consumo de chá tem efeitos inibidores sobre algumas bactérias orais. Objetivo: O objetivo deste estudo foi avaliar o efeito dos chás verde e preto sobre o pH salivar. Material e Métodos: neste estudo duplo-cego cruzado, amostras salivares de 50 estudantes saudáveis do sexo masculino da Faculdade de Odontologia de Zahedan, com idades entre 20-22 anos, foram coletadas para avaliação do pH salivar. Todos os voluntários foram solicitados a consumir chá preto comercial no primeiro dia e, em seguida, amostras de saliva foram coletadas antes de beber o chá, imediatamente após beber o chá, 5 e 10 minutos após o consumo do chá. Alternando com o consumo do chá verde, no segundo dia, as amostras de saliva foram coletadas novamente. Em seguida, o pH salivar foi estimado com um medidor de pH digital. Os dados foram analisados por meio de teste t independente e teste t de amostras pareadas. Resultados: O pH salivar médio antes e após o consumo de chá verde foi de 7,15 ± 0,05 e 7,56 ± 0,09, respectivamente, o que apresentou uma diferença notável (p <0,001). Foi de 7,14 ± 0,05 e 7,51 ± 0,10, respectivamente, para o chá preto, com diferença significativa (p <0,0001). O pH salivar médio após o consumo de chá verde foi significativamente maior do que o chá preto (p = 0,006). Conclusão: A ingestão de chá verde e preto levou a um aumento significativo no pH salivar, que foi maior após o consumo de chá verde em comparação com o chá preto. Este estudo sugere os efeitos benéficos de beber chá em fornecer um ambiente alcalino na cavidade oral (AU)

Background: Some herbal products could affect on salivary pH and prevention of dental caries. Tea consumption has inhibition effects on some oral bacteria. Objective: The aim of this study was to evaluate the effect of green and black tea on salivary pH. Material and Methods: In this double blinded cross-over trial, salivary samples of 50 healthy male students of Zahedan Faculty of Dentistry, aged 20-22 years old were collected for evaluation of salivary pH. All volunteers were asked to consume commercially black tea on the first day and then saliva samples were collected before drinking tea and immediately after drinking tea and 5 and 10 minutes after tea consumption. With replacing consumption of green tea, at the second day, saliva samples were collected again. Then the salivary pH was estimated with a digital pH-meter. Data were analyzed through independent t-test and paired samples t-test. Results: Mean salivary pH before and after green tea consumption were 7.15±0.05 and 7.56±0.09, respectively, which showed a remarkable difference (p<0.001). It was 7.14±0.05 and 7.51 ± 0.10, respectively, for black tea, with significant difference (p<0.001). Mean salivary pH after green tea consumption was significantly higher than black tea (p= 0.006). Conclusion:Both green and black tea intake led to a significant rise in salivary pH, which was higher after green tea consumption compared to black tea. This study suggests the beneficial effects of drinking tea in providing an alkaline environment in oral cavity (AU)

Comparative effect of Camellia sinensis teas on object recognition test deficit and metabolic changes induced by cafeteria diet.

Objectives: Consumption of high-fat and high-sugar diets in Western countries has increased significantly causing major global health problems including metabolic syndrome and obesity. In addition, studies have suggested that obesity can lead to learning and memory deficits. In this context, the use of natural compounds with low costs, minor side effects and increased antioxidant activity, such as teas, could reduce the damages induced by obesity. We investigated the effect of white, green, red, and black teas (Camellia sinensis) and their possible neuroprotective mechanisms in an experimental obesity model induced by a cafeteria diet (CD). Methods: Female Swiss mice (20-30 g) were used; they received a normal diet or a hypercaloric diet (CD) during 8 weeks. Concomitantly, some mice received orally white, green, red, or black teas (1% dose) or water. Results: The mice subjected to CD showed weight gain, body fat accumulation, increased glucose, cholesterol, and triglycerides, associated to recognition memory deficits and increased reactive species (RS) levels and acetylcholinesterase (AChE) activity in the hippocampus. All teas significantly reduced AChE activity and partially reduced fat accumulation. Green and red teas reduced memory deficit. White, green, and black teas reduced RS levels, while only green and black tea reduced plasma triglyceride levels. Discussion: According to the results obtained it is possible to conclude that green tea was better than other teas in reducing effects of the CD model, being able to protect a greater number of parameters.

Influence of preparation procedures on the phenolic content, antioxidant and antidiabetic activities of green and black teas

The influence of common tea preparation procedures (temperature, infusion time, consumption time interval and tea bag/loose-leaf) and the type of water used, on the total phenolic content (TPC), the radical scavenging activity and the α-glucosidase inhibitory activity were assessed. Higher TPC and antioxidant activity were obtained when using lower mineralized waters. Tea bags also evidenced higher antioxidant activity than loose-leaf samples. Under the same conditions (90 ºC and five minutes of infusion time) green tea contains almost twice the quantity of polyphenols and the free radical scavenging ability of black tea. In the α-glucosidase assay all infusions were active (97-100 %). Furthermore, HPLC allowed to identify some of the polyphenols present in both teas and to monitor their composition change with time. After twenty-four hours, the antioxidant activity was maintained without significant changes, but a small decrease in enzyme inhibition was observed, although this activity was still very high

Black and white teas as potential agents to combine with amphotericin B and protect red blood cells from amphotericin B-mediated toxicity / Chá preto e branco de Camellia sinensis como potenciais agentes para associar com anfotericina B

Amphotericin B is a fungicidal substance that is treatment of choice for most systemic fungal infections affecting immunocompromised patients. However, severe side effects have limited the utility of this drug. The aim of this study was to evaluate the antifungal effect of the combination of amphotericin B with black tea or white tea and protective of citotoxic effect. The present study shows that white and black teas have additive effects with amphotericin B against some species Candida. In addition, the combination of white and black tea with amphotericin B may reduce the toxicity of amphotericin B to red blood cells. Our results suggest that white and black tea is a potential agent to combine with amphotericin for antifungal efficacy and to reduce the amphotericin dose to lessen side effects.(AU)

A anfotericina B é o tratamento de escolha para a maioria das infecções fúngicas sistémicas que afetam os doentes imunocomprometidos. No entanto, efeitos secundários graves têm limitado a utilidade desta droga. O objetivo deste estudo foi avaliar o efeito antifúngico da combinação de anfotericina B com chá preto ou chá branco, bem como o efeito citotóxico desta combinação sobre hemáceas. O presente estudo demonstra que o chá branco e preto de Camellia sinensis têm efeitos aditivos com anfotericina B contra algumas espécies de Candida sp. Além disso, a combinação de chá branco e preto com anfotericina B pode reduzir a toxicidade da anfotericina B em hemáceas. Nossos resultados sugerem que o chá branco e preto são agentes potenciais para associação com anfotericina B contribuindo para eficácia antifúngica, bem como redução de toxicidade.(AU)

Black and white teas as potential agents to combine with amphotericin B and protect red blood cells from amphotericin B-mediated toxicity / Chá preto e branco de Camellia sinensis como potenciais agentes para associar com anfotericina B

Abstract Amphotericin B is a fungicidal substance that is treatment of choice for most systemic fungal infections affecting immunocompromised patients. However, severe side effects have limited the utility of this drug. The aim of this study was to evaluate the antifungal effect of the combination of amphotericin B with black tea or white tea and protective of citotoxic effect. The present study shows that white and black teas have additive effects with amphotericin B against some species Candida. In addition, the combination of white and black tea with amphotericin B may reduce the toxicity of amphotericin B to red blood cells. Our results suggest that white and black tea is a potential agent to combine with amphotericin for antifungal efficacy and to reduce the amphotericin dose to lessen side effects.

Resumo A anfotericina B é o tratamento de escolha para a maioria das infecções fúngicas sistémicas que afetam os doentes imunocomprometidos. No entanto, efeitos secundários graves têm limitado a utilidade desta droga. O objetivo deste estudo foi avaliar o efeito antifúngico da combinação de anfotericina B com chá preto ou chá branco, bem como o efeito citotóxico desta combinação sobre hemáceas. O presente estudo demonstra que o chá branco e preto de Camellia sinensis têm efeitos aditivos com anfotericina B contra algumas espécies de Candida sp. Além disso, a combinação de chá branco e preto com anfotericina B pode reduzir a toxicidade da anfotericina B em hemáceas. Nossos resultados sugerem que o chá branco e preto são agentes potenciais para associação com anfotericina B contribuindo para eficácia antifúngica, bem como redução de toxicidade.

Black and white teas as potential agents to combine with amphotericin B and protect red blood cells from amphotericin B-mediated toxicity

Abstract Amphotericin B is a fungicidal substance that is treatment of choice for most systemic fungal infections affecting immunocompromised patients. However, severe side effects have limited the utility of this drug. The aim of this study was to evaluate the antifungal effect of the combination of amphotericin B with black tea or white tea and protective of citotoxic effect. The present study shows that white and black teas have additive effects with amphotericin B against some species Candida. In addition, the combination of white and black tea with amphotericin B may reduce the toxicity of amphotericin B to red blood cells. Our results suggest that white and black tea is a potential agent to combine with amphotericin for antifungal efficacy and to reduce the amphotericin dose to lessen side effects.

Resumo A anfotericina B é o tratamento de escolha para a maioria das infecções fúngicas sistémicas que afetam os doentes imunocomprometidos. No entanto, efeitos secundários graves têm limitado a utilidade desta droga. O objetivo deste estudo foi avaliar o efeito antifúngico da combinação de anfotericina B com chá preto ou chá branco, bem como o efeito citotóxico desta combinação sobre hemáceas. O presente estudo demonstra que o chá branco e preto de Camellia sinensis têm efeitos aditivos com anfotericina B contra algumas espécies de Candida sp. Além disso, a combinação de chá branco e preto com anfotericina B pode reduzir a toxicidade da anfotericina B em hemáceas. Nossos resultados sugerem que o chá branco e preto são agentes potenciais para associação com anfotericina B contribuindo para eficácia antifúngica, bem como redução de toxicidade.

GC-MS based metabolite profiling and angiotensin I-converting enzyme inhibitory property of black tea extracts

Abstract Angiotensin I-converting enzyme inhibitors are used as therapeutic agents for the treatment of hypertension. Regular consumption of black tea (Camellia sinensis (L.) Kuntze, Theaceae) has been reported to lower blood pressure. The aims of the present work were to compare chemical composition and angiotensin I-converting enzyme inhibitory properties of infusion and decoction of four samples of black tea. GC/MS based metabolomics approach helped in identification of fifty-one metabolites including ten organic acids, one inorganic acid, sixteen amino acids, two sugars, five sugar alcohols, fifteen phenols and flavonoids, two fatty acids from infusions and decoctions of four black tea samples. Partial least squares discriminant analysis and orthogonal partial least squares discriminant analysis models showed good classification among the two groups, diffusion and infusion, based on metabolites. Both infusion and decoction inhibited the enzyme. However, the activity differed with samples. Multivariate analysis also segregated extracts on the basis of activity. Thearubigin, theaflavin, catechin inhibited the enzyme. Epicatechin, epigallocatechin gallate, gallic acid, caffeine showed lower activity.

Black and white teas as potential agents to combine with amphotericin B and protect red blood cells from amphotericin B-mediated toxicity

Abstract Amphotericin B is a fungicidal substance that is treatment of choice for most systemic fungal infections affecting immunocompromised patients. However, severe side effects have limited the utility of this drug. The aim of this study was to evaluate the antifungal effect of the combination of amphotericin B with black tea or white tea and protective of citotoxic effect. The present study shows that white and black teas have additive effects with amphotericin B against some species Candida. In addition, the combination of white and black tea with amphotericin B may reduce the toxicity of amphotericin B to red blood cells. Our results suggest that white and black tea is a potential agent to combine with amphotericin for antifungal efficacy and to reduce the amphotericin dose to lessen side effects.

Resumo A anfotericina B é o tratamento de escolha para a maioria das infecções fúngicas sistémicas que afetam os doentes imunocomprometidos. No entanto, efeitos secundários graves têm limitado a utilidade desta droga. O objetivo deste estudo foi avaliar o efeito antifúngico da combinação de anfotericina B com chá preto ou chá branco, bem como o efeito citotóxico desta combinação sobre hemáceas. O presente estudo demonstra que o chá branco e preto de Camellia sinensis têm efeitos aditivos com anfotericina B contra algumas espécies de Candida sp. Além disso, a combinação de chá branco e preto com anfotericina B pode reduzir a toxicidade da anfotericina B em hemáceas. Nossos resultados sugerem que o chá branco e preto são agentes potenciais para associação com anfotericina B contribuindo para eficácia antifúngica, bem como redução de toxicidade.

Antioxidant potential of yerba mate (Ilex paraguariensis St. Hil.) extracts in Saccharomyces cerevisae deficient in oxidant defense genes / Potencial antioxidante de extratos de erva-mate (Ilex paraguariensis St. Hil.) em Saccharomyces cerevisiae deficientes para genes de defesa oxidante

Abstract Yerba-mate (Ilex paraguariensis St. Hil) is mainly consumed as chimarrão, a hot drink highly appreciated in Brazil, Argentina, Paraguay and Uruguay. This study evaluated the antioxidant potential of aqueous extracts of I. paraguariensis precipitated with ethanol. The leaves were processed as for tea product (TM) and oxidized (OX). The antioxidant potential was evaluated in cells of Saccharomyces cerevisiae deficient in antioxidant defense genes. Three strains evaluated were: a wild (EG) and two mutants (ctt1 e ctt1sod1). These strains were pre-treated with the yerba-mate extracts (TM e OX) and submitted to oxidative stress induced by hydrogen peroxide. None of the extracts produced loss of cell viability. The extracts exerted antioxidant activity, protecting the strains (except sod1ctt1). The TM extract was more effective than OX. I. paraguariensis extracts showed a potential to be explored in the development of new products.(AU)

Resumo A erva-mate (Ilex paraguariensis St. Hil) é consumida principalmente como chimarrão, uma bebida quente muito apreciada no Brasil, Argentina, Paraguai e Uruguai. Este estudo avaliou o potencial antioxidante de extratos aquosos de I. paraguariensis precipitado com etanol. Folhas de erva-mate foram processados de maneira semelhante ao processamento do chá-preto (OX) e na forma de mate (TM). O potencial antioxidante foi avaliado sobre células de Saccharomyces cerevisiae deficientes para genes de defesa antioxidante. Três linhagens celulares foram estudadas: uma selvagem (EG) e duas mutantes (ctt1 e ctt1sod1). As linhagens foram pré-tratadas com os extratos de erva-mate (TM e OX) e submetidos ao estresse oxidativo induzido por peróxido de hidrogênio. Nenhum dos extratos produziu perda de viabilidade celular. Os extratos exerceram atividade antioxidante, protegendo as linhagens (exceto a sod1ctt1). O extrato TM foi mais eficaz em relação ao OX. Extratos de I. paraguariensis apresentaram potencial para ser explorado no desenvolvimento de novas formulações.(AU)

Antioxidant potential of yerba mate (Ilex paraguariensis St. Hil.) extracts in Saccharomyces cerevisae deficient in oxidant defense genes / Potencial antioxidante de extratos de erva-mate (Ilex paraguariensis St. Hil.) em Saccharomyces cerevisiae deficientes para genes de defesa oxidante

Abstract Yerba-mate (Ilex paraguariensis St. Hil) is mainly consumed as “chimarrão”, a hot drink highly appreciated in Brazil, Argentina, Paraguay and Uruguay. This study evaluated the antioxidant potential of aqueous extracts of I. paraguariensis precipitated with ethanol. The leaves were processed as for tea product (TM) and oxidized (OX). The antioxidant potential was evaluated in cells of Saccharomyces cerevisiae deficient in antioxidant defense genes. Three strains evaluated were: a wild (EG) and two mutants (ctt1Δ e ctt1Δsod1Δ). These strains were pre-treated with the yerba-mate extracts (TM e OX) and submitted to oxidative stress induced by hydrogen peroxide. None of the extracts produced loss of cell viability. The extracts exerted antioxidant activity, protecting the strains (except sod1∆ctt1∆). The TM extract was more effective than OX. I. paraguariensis extracts showed a potential to be explored in the development of new products.

Resumo A erva-mate (Ilex paraguariensis St. Hil) é consumida principalmente como “chimarrão”, uma bebida quente muito apreciada no Brasil, Argentina, Paraguai e Uruguai. Este estudo avaliou o potencial antioxidante de extratos aquosos de I. paraguariensis precipitado com etanol. Folhas de erva-mate foram processados de maneira semelhante ao processamento do chá-preto (OX) e na forma de mate (TM). O potencial antioxidante foi avaliado sobre células de Saccharomyces cerevisiae deficientes para genes de defesa antioxidante. Três linhagens celulares foram estudadas: uma selvagem (EG) e duas mutantes (ctt1Δ e ctt1Δsod1Δ). As linhagens foram pré-tratadas com os extratos de erva-mate (TM e OX) e submetidos ao estresse oxidativo induzido por peróxido de hidrogênio. Nenhum dos extratos produziu perda de viabilidade celular. Os extratos exerceram atividade antioxidante, protegendo as linhagens (exceto a sod1Δctt1Δ). O extrato TM foi mais eficaz em relação ao OX. Extratos de I. paraguariensis apresentaram potencial para ser explorado no desenvolvimento de novas formulações.

Chemical characterization of heteropolysaccharides from green and black teas (Camellia sinensis) and their anti-ulcer effect.

In order to obtain polysaccharides from green and black teas (Camellia sinensis), commercial leaves were submitted to infusion and then to alkaline extraction. The extracts were fractionated by freeze-thawing process, giving insoluble and soluble fractions. Complex arabinogalactan protein from the soluble fractions of both teas (GTPS and BTPS) were determined by methylation analysis and (1)H/(13)C-HSQC spectroscopy, showing a main chain of (1→3)-ß-Galp, substituted at O-6 by (1→6)-linked ß-Galp with side chains of α-Araf and terminal units of α-Araf, α-Fucp and α-Rhap. A highly branched heteroxylan from the insoluble fractions (GTPI and BTPI) showed in methylation analysis and (1)H/(13)C-HSQC spectroscopy the main chain of (1→4)-ß-Xylp, substituted in O-3 by α-Araf, ß-Galp and α-Glcp units. Evaluating their gastroprotective activity, the fractions containing the soluble heteropolysaccharides from green (GTPS) and black teas (BTPS) reduced the gastric lesions induced by ethanol. Furthermore, the fraction of insoluble heteropolysaccharides of green (GTPI) and black (BTPI) teas also protected the gastric mucosa. In addition, the maintenance of gastric mucus and reduced glutathione (GSH) levels was involved in the polysaccharides gastroprotection.

Antioxidant potential of yerba mate (Ilex paraguariensis St. Hil.) extracts in Saccharomyces cerevisae deficient in oxidant defense genes

Abstract Yerba-mate (Ilex paraguariensis St. Hil) is mainly consumed as chimarrão, a hot drink highly appreciated in Brazil, Argentina, Paraguay and Uruguay. This study evaluated the antioxidant potential of aqueous extracts of I. paraguariensis precipitated with ethanol. The leaves were processed as for tea product (TM) and oxidized (OX). The antioxidant potential was evaluated in cells of Saccharomyces cerevisiae deficient in antioxidant defense genes. Three strains evaluated were: a wild (EG) and two mutants (ctt1 e ctt1sod1). These strains were pre-treated with the yerba-mate extracts (TM e OX) and submitted to oxidative stress induced by hydrogen peroxide. None of the extracts produced loss of cell viability. The extracts exerted antioxidant activity, protecting the strains (except sod1ctt1). The TM extract was more effective than OX. I. paraguariensis extracts showed a potential to be explored in the development of new products.

Resumo A erva-mate (Ilex paraguariensis St. Hil) é consumida principalmente como chimarrão, uma bebida quente muito apreciada no Brasil, Argentina, Paraguai e Uruguai. Este estudo avaliou o potencial antioxidante de extratos aquosos de I. paraguariensis precipitado com etanol. Folhas de erva-mate foram processados de maneira semelhante ao processamento do chá-preto (OX) e na forma de mate (TM). O potencial antioxidante foi avaliado sobre células de Saccharomyces cerevisiae deficientes para genes de defesa antioxidante. Três linhagens celulares foram estudadas: uma selvagem (EG) e duas mutantes (ctt1 e ctt1sod1). As linhagens foram pré-tratadas com os extratos de erva-mate (TM e OX) e submetidos ao estresse oxidativo induzido por peróxido de hidrogênio. Nenhum dos extratos produziu perda de viabilidade celular. Os extratos exerceram atividade antioxidante, protegendo as linhagens (exceto a sod1ctt1). O extrato TM foi mais eficaz em relação ao OX. Extratos de I. paraguariensis apresentaram potencial para ser explorado no desenvolvimento de novas formulações.

Determinação da atividade antioxidante In vitro das bebidas de café e chás verde e preto / Determination of In vitro antioxidant activity of the beverages of coffee, green tea and black tea

Conforme demonstrado em diversos estudos, determinadas plantas e alimentos, apresentam propriedades protetoras à saúde devido à presença de antioxidantes. Sendo assim, o presente trabalho teve como objetivo comparar o efeito antioxidante in vitro de bebidas comercializadas de café, chá verde e chá preto, utilizando a combinação de diferentes metodologias. As bebidas foram preparadas no momento de uso, de acordo com as especificações do fabricante. Foram realizados testes para determinar o teor de polifenóis nas bebidas, e avaliar o seu poder redutor, bem como sua capacidade de quelar íons de metais de transição (Fe2+) sequestrar radicais livres, e inibir a peroxidação de lipídeos. O café apresentou maior teor de compostos fenólicos, seguido do chá verde e do chá preto (p<0,05). A análise dos resultados não revelou diferenças entre as três bebidas analisadas em relação ao poder redutor e à capacidade de inibir a peroxidação de lipídeos (p>0,05). A bebida de café apresentou uma maior atividade quelante do que o chá preto enquanto que o chá preto e o café apresentaram maior capacidade sequestrante de radicais DPPH em comparação com o chá verde. Os dados obtidos permitem sugerir que a bebida de café, provavelmente por ter maior concentração de polifenóis, pode ser considerada a melhor no que diz respeito à atividade antioxidante. Assim, a bebida de café, além de ser uma das bebidas mais populares do mundo por seu aroma e sabor, poderia também contribuir para a prevenção de danos oxidativos de maneira mais eficiente que os chás analisados neste estudo.(AU)

Numerous studies have demonstrated that certain plants and foods exhibit health protective properties due to the presence of antioxidants. In this sense, the present study aimed to compare the in vitro antioxidant effect of the commercialized beverages of coffee, green tea and black tea by using a combination of different methodologies. The beverages were prepared at the time of use, according to the manufacturer?s specifications. We determined the polyphenol content in the beverages and examined their reducing power, as well as their ability to chelate transition metal ions (Fe2+), scavenge free radicals, and inhibit lipid peroxidation. The beverage of coffee contained the highest amounts of phenolic compounds, being followed by green tea and black tea (p<0.05). The results revealed no differences among the three beverages regarding their reducing power and lipid peroxidation-inhibiting activity (p>0.05). The beverage of coffee displayed higher metal chelating ability than black tea. The beverages of black tea and coffee scavenged DPPH radical more effectively than green tea. The data obtained suggest that the beverage of coffee can be considered the best one regarding the antioxidant activity, probably due to its highest content of polyphenols. Thus, the beverage of coffee, one of the most popular beverages in the world for its aroma and flavor, could also contribute to prevent the oxidative damage more efficiently than the teas analyzed in this study.(AU)

Gastroprotective bio-guiding fractionation of hydro-alcoholic extracts from green- and black-teas (Camellia sinensis).

Hydro-alcoholic extracts from leaves of Camellia sinensis (green- and black-tea leaves) were submitted to a fractionation, promoting the compound separation according to their polarity, and analyzed by ultra-high performance liquid chromatography-mass spectrometry. A wide range of compounds could be identified, such as catechins and their gallate (esters) or oxidation derivatives (theaflavins), glycosylated flavonoids and other phenolics, as well as lipids, saponins and alkaloids. Also have been developed, via bio-guided examination, the gastroprotective property of the compounds identified. The samples were assayed using the model of acute gastric lesions induced in rats by ethanol. Hydro-alcoholic extracts of green-tea and black-tea protected the gastric mucosa with ED50=3.6 and 10.2mg/kg, respectively, with participation of gastric mucus and reduced glutathione (GSH). The ethyl acetate fraction from green-tea and aqueous fraction from black-tea were, respectively, 6 and 10 times more effectiveness than the initial extracts. Moreover, the epigallocatechin gallate (EGCG, 0.204mg/kg), a main component of ethyl acetate fraction from green tea, reduced the gastric lesion by 56% and restored the mucus levels, however the rutin (0.0133mg/kg), a flavonoid found in the most active fraction of black-tea, was less significant at the natural concentrations. These results have confirmed that the different compounds present in green- and black-tea hydro-alcoholic extracts and partitioned fractions produce relevant gastroprotection mainly via maintenance of the protective factors, mucus and GSH.

Uso do chá preto (Camellia sinensis) no controle do diabetes mellitus / Use of black tea (Camellia sinensis) in the control of diabetes mellitus

Diabetes mellitus é uma doença que afeta milhões de pessoas em todo o mundo, sendo caracterizada por distúrbios que alteram o metabolismo de carboidratos, lipídios e proteínas. Os hábitos alimentares exercem um papel muito importante para o seu controle e a ingestão do chá preto (Camellia sinensis), uma das bebidas mais consumidas no mundo, está associada a vários benefícios sobre a saúde, principalmente no controle de doenças crônicas, como o diabetes, e suas complicações. Este artigo apresenta uma revisão atualizada dos estudos sobre a utilização do chá, principalmente o chá preto, seus constituintes, metabolismo e mecanismos de ação e seu emprego como nutracêutico no controle do diabetes

Diabetes mellitus is a disease that affects millions of people around the world, characterized by abnormalities in the metabolism of carbohydrates, lipids and proteins. The diet plays a very important part in its control and the intake of black tea (Camellia sinensis), one of the most consumed beverages in the world, is associated with several health benefits, especially in the control of chronic diseases, such as diabetes, and its complications. This paper presents an updated review of the literature on the use of teas, especially black tea - its constituents, metabolism and mechanisms of action and its use as a nutraceutical in the control of diabetes.