RESUMO
SUMMARY: Although tacrolimus (TAC) significantly reduces allograft rejection incidence in solid-organ transplantation, its long-term use is associated with an increased risk of TAC-induced nephrotoxicity. In this study, we investigated the renoprotective effects of green tea extract (GTE) with or without the dipeptidyl peptidase 4 inhibitor, gemigliptin, by assessing serum creatinine levels, the amount of proteinuria, and histopathology in TAC-induced nephrotoxicity. TAC-induced nephrotoxicity was induced by intraperitoneal TAC injection, GTE was administered via subcutaneous injection, and gemigliptin was administered orally. Mice with TAC-induced nephrotoxicity exhibited a significant increase in both serum creatinine levels and 24-hour urine protein. However, when treated with GTE via subcutaneous injection, mice showed a decrease in serum creatinine levels and the amount of proteinuria. When GTE was combined with gemigliptin, further renoprotective effects were observed in biochemical assessments, consistent with the attenuation of TAC-induced nephrotoxicity in histopathology. The expression of p53 protein was lower in the mice treated with the combination of GTE and gemigliptin compared to mice with TAC-induced nephrotoxicity. Our results demonstrate that the combination of GTE and gemigliptin treatment reveals synergistic renoprotective effects by decreasing the expression of p53 protein. These findings suggest that the combination of GTE and gemigliptin could potentially be used as a prophylactic or therapeutic strategy for TAC-induced nephrotoxicity.
Aunque tacrolimus (TAC) reduce significativamente la incidencia de rechazo de aloinjertos en trasplantes de órganos sólidos, su uso a largo plazo se asocia con un mayor riesgo de nefrotoxicidad inducida por TAC. En este estudio, investigamos los efectos renoprotectores del extracto de té verde (GTE) con o sin el inhibidor de la dipeptidil peptidasa 4, gemigliptina, mediante la evaluación de los niveles de creatinina sérica, la cantidad de proteinuria y la histopatología en la nefrotoxicidad inducida por TAC. La nefrotoxicidad inducida por TAC se indujo mediante inyección intraperitoneal de TAC, el GTE se administró mediante inyección subcutánea y la gemigliptina se administró por vía oral. Los ratones con nefrotoxicidad inducida por TAC mostraron un aumento significativo tanto en los niveles de creatinina sérica como en la proteína en orina de 24 horas. Sin embargo, cuando se trataron con GTE mediante inyección subcutánea, los ratones mostraron una disminución en los niveles de creatinina sérica y en la cantidad de proteinuria. Cuando se combinó GTE con gemigliptina, se observaron efectos renoprotectores adicionales en las evaluaciones bioquímicas, lo que concuerda con la atenuación de la nefrotoxicidad inducida por TAC en histopatología. La expresión de la proteína p53 fue menor en los ratones tratados con la combinación de GTE y gemigliptina en comparación con los ratones con nefrotoxicidad inducida por TAC. Nuestros resultados demuestran que la combinación de tratamiento con GTE y gemigliptina revela efectos renoprotectores sinérgicos al disminuir la expresión de la proteína p53. Estos hallazgos sugieren que la combinación de GTE y gemigliptina podría usarse potencialmente como estrategia profiláctica o terapéutica para la nefrotoxicidad inducida por TAC.
Assuntos
Animais , Camundongos , Piperidonas/administração & dosagem , Pirimidinas/administração & dosagem , Chá , Extratos Vegetais/administração & dosagem , Tacrolimo/toxicidade , Nefropatias/tratamento farmacológico , Piperidonas/farmacologia , Pirimidinas/farmacologia , Extratos Vegetais/farmacologia , Substâncias Protetoras , Sinergismo Farmacológico , Imunossupressores/toxicidade , Rim/efeitos dos fármacos , Nefropatias/induzido quimicamenteRESUMO
Periodontal disease and osteoporosis are characterized by bone resorption, and researchers have shown an association between these two diseases through increasing loss of systemic bone mass and triggering alveolar bone loss. Green tea is a common and easily accessible beverage, and evidences show that flavonoid epigallocatechin gallate (EGCG) could decrease bone loss in pathologies such as osteoporosis and periodontal disease. In order to verify its possible effects and apply them in the treatment and prevention of these diseases, this investigation aimed to evaluate the influence of green tea extract (GTE) on bone metabolism of ovariectomized rats after experimental periodontal disease (EPD) by histological, morphological and microtomographic parameters. Wistar female rats were divided into Sham, Sham + EPD, Sham + EPD + GTE, OVX, OVX + EPD and OVX + EPD + GTE groups. Immediately after surgery, gavage administration of 50 mg/kg of green tea extract (GTE) was performed for 60 days, with subsequent induction of periodontal disease by ligature 15 days before euthanasia. Mandible and femur samples were collected for histological, morphometric and microtomographic analysis. The results were analysed by means of statistical software with significance set at 5%. Histological and morphometric analysis showed a significant decrease in alveolar and femoral trabecular bone loss in groups that received GTE. Microtomographic results showed that trabecular thickness and bone surface density values in alveolar bone interradicular septum of the OVX + EPD + GTE groups were similar to the Sham group. The results obtained suggest that green tea extract may improve bone metabolism in osteoporotic rats with periodontal disease.
Assuntos
Antioxidantes/farmacologia , Doenças Periodontais/tratamento farmacológico , Extratos Vegetais/farmacologia , Animais , Densidade Óssea/efeitos dos fármacos , Catequina/análogos & derivados , Feminino , Osteoporose/patologia , Doenças Periodontais/patologia , Ratos , Ratos WistarRESUMO
The aim of this research was to develop and characterize five gelled double emulsions based on chia mucilage (CM) and different biopolymers (κ-carrageenan, C; locust bean gum, L; thixogum, T; and whey protein concentrate, W) loaded with green tea extract (GTE). Gelled double emulsions consisted of W1 (whey-protein-concentrate/sodium-azide/NaCl/GTE)/O and (PGPR/canola-oi)/W2 (CM, CMC, CML, CMT and CMW), and were characterized based on physicochemical properties during 35 days of storage. Optical microscopy clearly showed the drops of the internal phase surrounded by droplets of oil dispersed in the second aqueous phase; the droplet size was higher for CMT and lowest for CMW. In addition, all emulsions were highly stable at creaming and were effective in reducing the loss of antioxidant activity (88.82%) and total phenols (64.26%) during storage; CMT, CML and CM were the most effective. Furthermore, all emulsions showed a protective effect by modulating the release of the GTE in a simulated gastrointestinal environment, allowing a controlled release during the gastric-intestinal digestion phases and reaching its maximum release in the intestinal phase (64.57-83.31%). Thus, gelled double emulsions are an alternative for the preservation of GTE and could be a potential alternative for their application in the development of functional foods.
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Type 2 diabetes mellitus (T2DM) is associated with premature atherosclerosis and arterial stiffening due to the accumulation of advanced glycation end-products in vessel walls. Green tea polyphenols are considered cardio-protective substances. In this randomised double-blind placebo-controlled trial (NCT02627898), we evaluated the effect of Green tea extract on arterial stiffness parameters, lipids, body composition and sRAGE levels. Twenty normotensive patients with T2DM treated with the standard therapy and statins, mean age 53.2 ± 9.4 years and mean BMI 30.1 ± 4.5 kg/m2, were randomised to receive a daily dose of 400 mg of green tea extract (polyphenols ≥90%, EGCG ≥45%) or placebo for 12 weeks. Compared to placebo, administration of green tea extract decreased central augmentation index (-3.05 ± 10.8% vs. 6.7 ± 0.1%, p = .04). These findings suggest that green tea extract could be used as an adjunct to the standard therapy to improve arterial stiffness in T2DM.
Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Metabolismo dos Lipídeos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Chá/química , Rigidez Vascular/efeitos dos fármacos , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Composição Corporal/efeitos dos fármacos , Índice de Massa Corporal , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Creatinina/sangue , Diabetes Mellitus Tipo 2/sangue , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Hemoglobinas Glicadas/metabolismo , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Polifenóis/administração & dosagem , Receptor para Produtos Finais de Glicação Avançada/sangue , Proteínas S100/sangue , Triglicerídeos/sangueRESUMO
BACKGROUND: Consumption of green tea has been associated with reduced risk of breast cancer. Hormonal modulation has been suggested as one of the potential underlying mechanisms; however, it has yet to be fully elucidated in large, long-term human clinical trials. OBJECTIVE: We investigated the effects of decaffeinated green tea extract (GTE) on circulating sex hormones and insulin-like growth factor (IGF) proteins. METHODS: We conducted a placebo-controlled double-blind randomized clinical trial recruiting from 8 clinical centers in Minnesota. Participants were 538 healthy postmenopausal women randomly assigned to the GTE group (463 completed the study; mean age = 60.0 y) and 537 to the placebo group (474 completed; mean age = 59.7 y). Women in the GTE group orally took 4 decaffeinated capsules containing 1315 mg total catechins including 843 mg epigallocatechin-3-gallate daily for 1 y, whereas women in the placebo group took similar capsules containing no tea catechins. Blood sex hormones (estrone, estradiol, androstenedione, testosterone, and sex hormone-binding globulin) and IGF proteins (IGF-1 and IGF binding protein-3) were quantified at baseline and months 6 (for IGF proteins only) and 12, and were assessed as secondary outcomes of the study using a mixed-effect repeated-measures ANOVA model. RESULTS: Women in the GTE group had significantly higher blood total estradiol (16%; P = 0.02) and bioavailable estradiol (21%; P = 0.03) than in the placebo group at month 12. There was a statistically significant interaction between GTE supplementation and duration of treatment on estradiol and bioavailable estradiol (both Ps for interaction = 0.001). The catechol-O-methyltransferase genotype did not influence blood sex hormones before or after GTE supplementation. The circulating concentrations of IGF proteins were comparable between GTE and placebo groups at all 3 time points. CONCLUSION: These results suggest that a 12-mo GTE supplementation significantly increases circulating estradiol concentrations in healthy postmenopausal women. This trial was registered at clinicaltrials.gov as NCT00917735.
Assuntos
Neoplasias da Mama , Catequina/farmacologia , Hormônios Esteroides Gonadais/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Extratos Vegetais/farmacologia , Chá/química , Idoso , Catequina/química , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Extratos Vegetais/química , Pós-MenopausaRESUMO
Cashew gum and maltodextrin microcapsules containing green tea leaf extracts were made using a spray-dryer. Green tea extracts were submitted to cytotoxicity analysis and characterization of bioactive compounds. Three formulations of microcapsules were performed, which were then submitted to characterization through morphological study, particle diameter and distribution, zeta potential, Exploratory Differential Calorimetry, entrapment efficiency, dissolution test and X-ray diffraction. The extract had a high bioactive compound content and no cytotoxicity was observed. The amorphous microcapsules presented irregular shapes with a circular predominance and dentate surface, mean diameters varying from 2.50 to 3.64⯵m, solubility ranging from 63% to 72.66%. Low values of microencapsulation efficiency, zeta potencial and dissolution profile were observed. The microparticles based on the dry extract of green tea present potential as a food ingredient and as a promoter of health benefits.
Assuntos
Anacardium/química , Camellia sinensis/química , Composição de Medicamentos/métodos , Polissacarídeos/química , Animais , Antioxidantes/análise , Antioxidantes/farmacologia , Calorimetria/métodos , Cápsulas , Linhagem Celular , Tamanho da Partícula , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Ratos , Solubilidade , Chá/química , Difração de Raios XRESUMO
Camellia sinensis, which is obtained from green tea extract (GTE), has been widely used in therapy owing to the antioxidant, chemoprotective, and anti-inflammatory activities of its chemical components. However, GTE is an unstable compound, and may undergo reactions that lead to a reduction or loss of its effectiveness and even its degradation. Hence, an attractive approach to overcome this problem to protect the GTE is its incorporation into liquid crystalline systems (LCS) that are drug delivery nanostructured systems with different rheological properties, since LCS have both fluid liquid and crystalline solid properties. Therefore, the aim of this study was to develop and characterize GTE-loaded LCS composed of polyoxypropylene (5) polyoxyethylene (20) cetyl alcohol, avocado oil, and water (F25E, F29E, and F32E) with different rheological properties and to determine their anti-inflammatory efficacy. Polarized light microscopy revealed that the formulations F25, F29, and F32 showed hexagonal, cubic, and lamellar liquid crystalline mesophases, respectively. Rheological studies showed that F32 is a viscous Newtonian liquid, while F25 and F29 are dilatant and pseudoplastic non-Newtonian fluids, respectively. All GTE-loaded LCS behaved as pseudoplastic with thixotropy; furthermore, the presence of GTE increased the S values and decreased the n values, especially in F29, indicating that this LCS has the most organized structure. Mechanical and bioadhesive properties of GTE-unloaded and -loaded LCS corroborated the rheological data, showing that F29 had the highest mechanical and bioadhesive values. Finally, in vivo inflammation assay revealed that the less elastic and consistent LCS, F25E and F32E presented statistically the same anti-inflammatory activity compared to the positive control, decreasing significantly the paw edema after 4 h; whereas, the most structured and elastic LCS, F29E, strongly limited the potential effects of GTE. Thereby, the development of drug delivery systems with suitable rheological properties may enhance GTE bioavailability, enabling its administration via the skin for the treatment of inflammation.
RESUMO
Se and green tea have been shown in epidemiological, observational and preclinical studies to be inversely related to the risk of developing colorectal cancer (CRC). However, there are limited studies to evaluate their regulatory effects on genes/proteins that relate to CRC oncogenesis in human subjects, such as selenoproteins, WNT signalling pathway, inflammation and methylation. This study examined the effects of supplementation of Se using Brazil nuts and green tea extract (GTE) capsules, alone and in combination, on targeted biomarkers. In total, thirty-two volunteers (>50 years of age) with plasma Se≤1·36 µmol/l were randomised to one of three treatment groups: nine to Se (approximately 48 µg/d) as six Brazil nuts, eleven to four GTE capsules (800 mg (-)-epigallocatechin-3-gallate) and twelve to a combination of Brazil nuts and GTE. Blood and rectal biopsies were obtained before and after each intervention. Plasma Se levels, rectal selenoprotein P (SePP) and ß-catenin mRNA increased significantly in subjects consuming Brazil nuts alone or in combination, whereas rectal DNA methyltransferase (DNMT1) and NF-κB mRNA were reduced significantly in subjects consuming GTE alone or in combination. None of the interventions significantly affected rectal acetylated histone H3 or Ki-67 expression at the protein level or plasma C-reactive protein. Effects of the combination of Brazil nuts and GTE did not differ from what would be expected from either agent alone. In conclusion, supplementation of Brazil nuts and/or GTE regulates targeted biomarkers related to CRC oncogenesis, specifically genes associated with selenoproteins (SePP), WNT signalling (ß-catenin), inflammation (NF-κB) and methylation (DNMT1). Their combination does not appear to provide additional effects compared with either agent alone.
Assuntos
Anticarcinógenos/uso terapêutico , Bertholletia , Camellia sinensis/química , Neoplasias Colorretais/prevenção & controle , Suplementos Nutricionais , Nozes , Extratos Vegetais/uso terapêutico , Idoso , Bertholletia/efeitos adversos , Bertholletia/química , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Suplementos Nutricionais/efeitos adversos , Estudos de Viabilidade , Feminino , Manipulação de Alimentos , Alimento Funcional/efeitos adversos , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Nozes/efeitos adversos , Nozes/química , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Folhas de Planta/química , Reto/metabolismo , Reto/patologia , Risco , Selênio/administração & dosagem , Selênio/efeitos adversos , Selênio/sangue , Selênio/uso terapêutico , Austrália do Sul/epidemiologiaRESUMO
A inserção de produtos de origem vegetal em cosméticos podem melhorar as suas características. Nesse estudo, objetivou-se o desenvolvimento de formulações fotoprotetoras contendo extrato glicólico de Camelia sinensis, a avaliação da atividade fotoprotetora in vitro após a adição do extrato vegetal, bem como a avaliação das características organolépticas, a determinação do valor de pH e comportamento reológico durante 30 dias de avaliação, quando as formulações foram armazenadas nas temperaturas de 25±2°C; 5±2 °C e 40±2 °C. Após 15 dias, alterações nas características organolépticas e reológicas foram observadas nas formulações armazenadas em altas temperaturas. Em 30 dias, as formulações mantidas a temperatura ambiente e em geladeira mantiveram as características organolépticas, apesar das alterações reológicas. Observou-se uma tendência a aumento do efeito fotoprotetor com a formulação contendo FPS15 e extrato glicólico de chá verde, entretanto, não se pode atribuir melhora na estabilidade física da emulsão pela adição do extrato.
The addition of plant material to a cosmetic may improve its characteristics. The stability profile allows the performance, safety, efficacy and consumer acceptance of an emulsion to be assessed. A stability study provides information about the behavior of the product over a given time interval, under various environmental conditions. The aims of this study were to prepare sunscreen formulations containing a glycolic extract of green tea (Camellia sinensis) and to assess the photoprotective activity in vitro, the organoleptic characteristics, pH and rheological behavior over a period of 30 days, during which the formulations were stored at temperatures of 25±2°C, 5±2°C and 40±2°C. After 15 days, changes in rheological characteristics were observed in the formulation stored at the higher temperatures. After 30 days, changes were observed at other temperatures. The addition of the extract significantly changed the rheological profile of the sunscreen formulations tested. An increase in the photoprotective effect was observed when the emulsion base was compared with the emulsion containing green tea extract. However, there was no evidence of an improvement of stability when the plant extract was added to the emulsions.
Assuntos
Camellia sinensis , Estabilidade de Cosméticos , Protetores SolaresRESUMO
O ovo é consumido in natura ou processado, e usado como matéria-prima em diversos produtos. A pasteurização e a atomização são os principais processamentos aplicados ao ovo. Diferentes condições de processamento, embalagem e estocagem podem afetar a estabilidade oxidativa lipídica e reduzir a proteção antioxidante natural do ovo. O uso de embalagens onde não haja contato do ovo com a luz e oxigênio, estocagem em temperaturas baixas e uso de antioxidantes podem prevenir a oxidação lipídica. Atualmente, os antioxidantes sintéticos são cada vez mais substituídos por antioxidantes naturais ou feita uma associação entre eles. O alecrim (Rosmarinus officinalis L.) e o chá verde (Camelia sinensis L) constam entre os vegetais com grande potencial antioxidante. Com base no exposto, os objetivos do trabalho foram: a) Padronizar o método do fosfomolibdênio para avaliação da capacidade antioxidante total da fração lipídica (CATL) do ovo; b) Investigar o efeito da pasteurização e da atomização do ovo no que se refere à capacidade antioxidante e à estabilidade oxidativa da fração lipídica do ovo; c) Avaliar a estabilidade oxidativa de ácidos graxos e a capacidade antioxidante do ovo integral pasteurizado atomizado, estocado a 5ºC, por 90 dias; d) Verificar por meio de teste de concentração de antioxidantes, a estabilidade oxidativa lipídica do ovo integral pasteurizado atomizado adicionado da mistura de extrato de alecrim, extrato de chá verde e BHA (butilato de hidroxianisol); e) Otimizar a concentração da mistura de extrato de alecrim, extrato de chá verde e BHA a ser adicionada ao ovo líquido integral pasteurizado, posteriormente atomizado, pelo modelo matemático proposto pela metodologia de superfície de resposta; f) Investigar o efeito da mistura otimizada de extrato de alecrim, extrato de chá verde e BHA na estabilidade oxidativa lipídica do ovo integral pasteurizado atomizado, estocado sob as temperaturas de 5°C e 25ºC, por 90 dias. O método do fosfomolidênio para medir a CATL do ovo apresentou adequação analítica, indicada pela equação de regressão (y = 13,705x + 0,0808), coeficiente de determinação (R2 = 0,9931), limite de detecção (0,005mg α-tocoferol/ mL), limite de quantificação (0,017mg α-tocoferol/ mL), coeficiente de correlação (r = 0,9965), sendo que a precisão não indicou dispersão ao redor da média. A CATL diminuiu com o progresso do processamento e o inverso foi observado quanto aos lipídios, 7-CETO (7-cetocolesterol) e TBARS (substâncias reativas ao ácido tiobarbitúrico). O ovo integral pasteurizado atomizado (OIPA) mantido sob condições de estocagem consideradas ideais permaneceu estável em relação à hidratação, a CATL e as TBARS. Pelo teste de concentração de antioxidantes, foram ensaiadas dez misturas (alecrim, chá verde e BHA) no OIPA e refletiu na sua estabilidade oxidativa lipídica, verificada pelas TBARS, CATL, CT-F (capacidade redutora pelo reativo de Folin - Ciocalteau), AGL (ácidos graxos livres) e AS-233 (substâncias absorvidas a 233 nm). Os resultados mostraram que a metodologia de superfície de resposta (RSM) foi adequada para descrever a formação dos AGL e AS-233 no OIPA, podendo serem usadas para fins preditivos. A otimização da mistura de antioxidantes baseou-se no modelo matemático obtido com as AS-233, onde foi proposto como sistema antioxidante 150ppm de BHA, 600ppm de alecrim e 300ppm de chá verde. As condições de estocagem adotadas e a adição dos antioxidantes foram efetivas para manter estável o OIPA, sendo mais efetivo quando estocado a 5°C. Concluíu-se que o método do fosfomolibdênio apresentou adequação analítica. A pasteurização não afetou os parâmetros analisados (lipídios, TBARS, CATL e 7-CETO), mas a atomização provocou diminuição significativa da CATL, e elevação dos lipídios, TBARS e 7-CETO. Foi mantida a hidratação e a estabilidade oxidativa do OIPA estocado por 90 dias a 5°C, indicando que as condições de embalagem e estocagem foram efetivas. Pelo modelo matemático proposto pela RSM foi constatado que apenas os AGL e AS-233 podem ser usados para fins preditivos, optando-se pela otimização da concentração da mistura de antioxidantes, usando apenas o modelo matemático obtido nas AS-233. Com a presença ou não de antioxidantes, o OIPA estocado a 5°C, ao longo dos 90 dias, apresentou-se mais estável quanto à hidratação e à oxidação lipídica
Egg is consumed in natura or processed and is used as raw material in various food products. The pasteurization and spray-drying processes are the main processing applied to the egg. Different processing conditions, packaging and storage can affect the lipid oxidative stability and may reduce the natural antioxidant protection of this product. The use of packages in which the egg has no contact with light and oxygen, storage at low temperatures, and the use of antioxidants can prevent lipid oxidation. Currently, synthetic antioxidants have been increasingly replaced by natural antioxidants or an association between synthetic and natural antioxidants is adopted by food companies. Rosemary (Rosmarinus officinalis L.) and green tea (Camellia sinensis L) are among the vegetables that present the highest antioxidant potential. Based on the above-mentioned considerations, the objectives of this research were: a) To standardize the method of phosphomolybdenum to evaluate the total antioxidant capacity of lipid fraction (CATL) egg; b)To investigate the effect of pasteurization and spray-drying on the antioxidant capacity and oxidative stability of the lipid fraction of egg; c) To assess the oxidative stability of fatty acids and the antioxidant capacity of whole egg subjected to pasteurization followed by spray-drying, stored at 5ºC for 90 days, d) To evaluate the by testing the concentration of antioxidants, oxidative stability of the lipid fraction of egg subjected to pasteurization and spray drying, added with a mixture of rosemary and green tea extracts and BHA (butylated hydroxyanisole); e) To optimize the concentration of the mixture composed of rosemary and green tea extracts and BHA to be added to pasteurized liquid egg (and further subjected to spray-drying) by using Response Surface Methodology; f) To investigate the effect of the addition of this optimized mixture of antioxidants on of the lipid fraction of spray-dried egg, stored at temperatures of 5 and 25°C for 90 days. The phosphomolybdenum method CATL of egg presented analytical suitability once it presented a high coefficient of determination (R2 = 0,9931), a regression equation expressed as y = 13.705 + 0.0808 x, a limit of detection of 0.005 mg α- tocopherol/mL, a limit of quantitation of 0.017 mg α-tocopherol/mL, a significant and high correlation coefficient (r = 0.9965), and the accuracy did not indicate dispersion around the mean. The CATL decreased with the progress of processing and the reverse was observed for the lipids, 7-CETO (7-ketocholesterol) and TBARS (thiobarbituric acid reactive substances). The pasteurized spray-dried egg (OIPA), which was kept under ideal storage conditions, remained stable in relation to moisture content, CATL and TBARS. In order to test the concentration of antioxidants to be added to OIPA, a total of 10 mixtures (rosemary, green tea and BHA) were assayed. The addition of antioxidants resulted in a higher oxidative stability of the lipid fraction as measured by TBARS, CATL, CT-F (reduction capacity by using the Folin-Ciocalteau reagent), AGL (free fat acids) and AS-233 (substances that absorb at 233 nm). The results showed that the response surface methodology (RSM) was adequate to describe the development of free fat acids and AS-233 in OIPA, and the RSM model proposed for AS-233 can be used for prediction purposes. The optimization of the antioxidant mixture based on the mathematical model proposed for AS-233 indicated that the mixture of 150ppm of BHA, 600ppm of rosemary extract and 300ppm of green tea extract was the best combination of antioxidants. The adopted storage conditions and the addition of antioxidants to OIPA were effective to maintain the response variables stable, and the stability was higher when OIPA was stored at 5°C. It was concluded that the method of phosphomolybdenum suitability presented analytically. The pasteurization did not affect the analyzed parameters (lipids, TBARS, CATL and 7-CETO), but the spray-drying caused a significant decrease CATL, and an increase in lipids, TBARS and 7-CETO. The hydration and the oxidative stability of OIPA remained stable for 90 days at 5°C, indicating that the packaging and storage conditions were effective. The RSM models proposed for free fat acids and AS-233 could be used for predictive purposes; however, the optimization procedure was performed taken into account only the AS-233 model. The OIPA stored at 5°C for 90 days, with or without the addition of the antioxidant mixture, was more stable in relation to hydration and lipid oxidation
Assuntos
Armazenamento de Materiais e Provisões , Ovos , Antioxidantes , Hidroxianisol Butilado , Embalagem de Produtos , Rosmarinus , Camellia sinensis , Pasteurização/métodosRESUMO
Cadmium (Cd), is an environmental and industrial pollutant that affects the male reproductive system. Cd induces its effect by affecting tissue antioxidant enzyme systems. Green tea extract (GTE) is an antioxidant and free radicals scavenger and has a chelating property. The purpose of this study was to investigate the protective effect of GTE against testes damage induced by Cd. Four groups of male rats, were utilized as following: Controls, GTE treated, Cd treated and Cd + GTE, treated rats at the same doses. The rats received GTE and or Cd orally in drinking water. After 5 weeks, the animals were sacrificed and testes were removed for microscopic and Biochemical evaluation. The levels of lipid peroxides (LPO) and glutathione (GSH) were detected in the tissue homogenates of rat testes. The current study showed marked morphological changes in the form of swelling, congestion, hemorrhage and necrosis in testes of rats treated with Cd alone. However, the rats treated with Cd+GTE showed milder edema, congestion and minute foci of necrosis in the testes. The LPO levels were significantly higher as compared to control and of GSH were significantly lower in Cd-treated rats but when GTE was co-administrated with Cd, there was an effective reduction in oxidative stress as shown by a significant rise of GSH level. In conclusion, the rats received GTE + Cd could enhance antioxidant/ detoxification system which consequently reduced the oxidative stress in rat testes. The beneficial effect of GTE is thus potentially reducing Cd toxicity and tissue damage.
El cadmio (Cd), es un contaminante del medio ambiente e industrial que afecta al sistema reproductivo masculino. Cd induce su efecto por afección de los sistemas enzimáticos antioxidantes de los tejidos. El extracto de té verde (ETV) es un antioxidante y buscador de radicales libres y tiene una propiedad quelante. El objetivo de este estudio fue investigar el efecto protector de ETV contra daños provocado por Cd a los testículos. Cuatro grupos de ratas macho, se utilizaron: Controles, tratados con ETV, tratados con Cd y tratados con Cd + ETV, todas las ratas tratadas con las mismas dosis. Las ratas recibieron ETV o Cd por vía oral en el agua potable. Después de 5 semanas, los animales fueron sacrificados y los testículos fueron retirados para la evaluación microscópica y bioquímica. Los niveles de peróxidos lípidos (LPO) y de glutation (GSH) fueron detectados en el tejido homogenizado de rata testículos. El estudio demostró marcados cambios morfológicos como inflamación, congestión, hemorragia y necrosis en los testículos de las ratas tratadas solamente con Cd. Sin embargo, las ratas tratadas con Cd + ETV mostraron leves signos de edema, congestión y focos de necrosis en los testículos. Los niveles de LPO fueron significativamente mayores en comparación con el control y la de GSH fue significativamente menor en las ratas tratadas con Cd, pero cuando ETV fue co-administrado con Cd, hubo una reducción efectiva en el estrés oxidativo, como lo demuestra el aumento significativo del nivel de GSH. En conclusión, las ratas recibieron GTE + Cd que podría aumentar el sistema antioxidante / desintoxicación, por tanto, reducir el estrés oxidativo en los testículos de ratas. El efecto beneficioso de GTE es reducir la toxicidad y el daño tisular causado Cd.