Chemical Composition, Antioxidant Potential, and Blood Glucose Lowering Effect of Aqueous Extract and Essential Oil of Thymus Serrulatus Hochst. Ex Benth.

Thymus serrulatus, an endemic plant of Ethiopia, is traditionally used to cure various diseases and as a food ingredient. In the Ethiopian folk medicine, the decoction is orally taken as a remedy to treat diabetes and high blood pressure. The purpose of the present study was to evaluate the antioxidant and antihyperglycemic effects of the aqueous extract and of the essential oil of Thymus serrulatus. The chemical composition of the aqueous extract was determined by LC-MS and the essential oil was characterized by GC-MS analysis. Radical scavenging assays, namely scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH•), hydroxyl (•OH), and nitric oxide (•NO), were used as a first approach to screen the potential antioxidant abilities of the samples. Alpha-amylase and α-glucosidase inhibitory studies were also employed to evaluate the in vitro antihyperglycemic potential of the plant. The in vivo blood glucose lowering effect of the extracts was assessed using hypoglycemic activity and the oral glucose tolerance test in normal and in streptozotocin induced diabetic mice. When compared to the aqueous extract, the essential oil showed superior radical scavenging activity, particularly for •NO, as well as greater inhibitory potency against α-amylase and α-glucosidase (IC50 = 0.01 mg/ml and 0.11 mg/ml, respectively). Both tested samples showed a statistically significant antihyperglycemic effect. The aqueous extract at 600 mg/kg exerted maximum antihyperglycemic activity (44.14%), followed by the essential oil (30.82%). Body weight and glucose tolerance parameters were also improved by the samples both in normal and diabetic mice. The findings of this study support the hypothesis that aqueous extract and essential oil of T. serrulatus are promising therapeutic agents.

Gluten-free green banana flour muffins: chemical, physical, antioxidant, digestibility and sensory analysis.

Considering the low availability of gluten-free products that are offered an affordable price and good sensory characteristics, the main objective of the study was developed a gluten-free muffin based on green banana flour and evaluate their physical-chemical and sensorial aspects. The quality of the muffin was analyzed through such moisture content, ashes, proteins, lipids, fiber, carbohydrates, total caloric content, yield mass, weight loss in the supply, antioxidant activity, protein digestibility, and hedonic scale. The results showed that the gluten-free muffin had a moisture content of 26.7%, ash of 2.39%, lipids of 15.4%, proteins of 10.3%, fibers of 1.2%, carbohydrates of 44.0%, the total caloric value of 261.2 kcal, high protein digestibility and moderate antioxidant activity. The acceptability index was 84.5%. It has been concluded that gluten-free muffin with green banana flour is a viable alternative for the reason that they have higher protein content than other alternative flours.

Araçá (Psidium cattleianum Sabine): bioactive compounds, antioxidant activity and pancreatic lipase inhibition / Araçá (Psidium cattleianum Sabine): compostos bioativos, atividade antioxidante e inibição da lipase pancreática

ABSTRACT: "Araçá" has been reported with different biological activities such as antioxidant, antiproliferative and antimicrobial as well as inhibitors of digestive enzymes. The digestive pancreatic lipase enzyme plays a fundamental role in lipid metabolism, and its inhibition has been studied as a target for obesity treatment. This study quantified the bioactive compounds present in different parts of "araçá" fruit and evaluated their antioxidant activity and lipase inhibition properties. Three samples were analyzed for total anthocyanins, total phenolic content, antioxidant activity and pancreatic lipase inhibition. Anthocyanins were reported only in pulp-peel of red "araçá" sample. Phenolic compounds concentration was higher in pulp-peel than in seeds for all samples. The antioxidant activity followed the same trend. A positive correlation was observed between total phenolic content and both antioxidant activity and lipase inhibition. Lipase inhibition activity was higher for pulp-peel compared to the seeds. Overall, the results showed that "araçá" fruit extracts could be beneficial for the treatment of obesity.

RESUMO: A fruta araçá tem sido destacada por suas diferentes atividades biológicas como antioxidante, antiproliferativa e antimicrobiana, além de inibidores de enzimas digestivas. A enzima digestiva lipase tem papel fundamental no metabolismo lipídico, e sua inibição tem sido estudada como alvo para o tratamento da obesidade. Este estudo teve como objetivo quantificar os compostos bioativos presentes em diferentes partes do fruto do araçá e avaliar sua atividade antioxidante e propriedades de inibição da lipase. Três amostras foram analisadas quanto a antocianinas totais, compostos fenólicos totais, atividade antioxidante e inibição da lipase pancreática. Antocianinas foram encontradas apenas na polpa-casca da amostra de araçá vermelho. A concentração de compostos fenólicos foi maior na polpa-casca do que nas sementes para todas as amostras. A atividade antioxidante seguiu a mesma tendência. Os compostos fenólicos totais, a atividade antioxidante e a inibição da lipase apresentaram uma correlação positiva. A atividade de inibição da lipase foi ligeiramente superior para a polpa-casca em comparação com as sementes. No geral, os resultados revelaram que os extratos da fruta do araçá podem ser benéficos para o tratamento da obesidade.

Physicochemical and antioxidant capacity analysis of colored sweet potato genotypes: in natura and thermally processed / Análises físico-químicas e capacidade antioxidante de genótipos coloridos de batata-doce in natura e termicamente processados

ABSTRACT: Sweet potato ( Ipomoea batatas (L.) Lam) is one of the most popular and ancient roots of Brazil and it can be consumed at different forms such as boiled, roasted or as sweets. Its cooking can lead to physicochemical transformations altering the nutritional properties. The objective of this study was to evaluate the physicochemical characteristics, bioactive compounds and antioxidant capacity of twelve sweet potato genotypes of varying pulp color in natura and roasted. Soluble solids, acidity, sugars, carotenoids, anthocyanins, phenolic compounds and antioxidant capacity were analyzed in the following sweet potatoes genotypes: cream pulp (Rubissol, Cuia, ILS03, ILS10, ILS12, ILS24 and ILS44); orange pulp (Amelia and Beauregard); and purple pulp (ILS56, ILS16 and ILS71). According to the results, it was observed a wide variation among the sweet potato genotypes for all analyzed parameters, in both preparation forms. The antioxidant capacity was a parameter with wide variation among genotypes, 210.29 to 7870.57µg trolox equivalent/g in in natura form and 673.26 to 17306.22µg trolox equivalent/g in roasted form. Soluble solids, acidity, sugars and bioactive compounds, with the exception of carotenoids, tended to be concentrated, also increases the total antioxidant capacity, in roasted sweet potatoes. In conclusion, genotype and the color of sweet potatoes were parameters that had an influence on its chemical composition. Cultivars such as Amelia and Beauregard stood out by the amounts of total soluble solids and carotenoids, respectively. The selections ILS 16 and ILS 56 are recommended as sources of anthocyanins. Thermal process influenced the concentration of antioxidant compounds and changed some physicochemical characteristics.

RESUMO: A batata-doce ( Ipomoea batatas (L.) Lam) é uma das raízes mais populares e antigas do Brasil, podendo ser consumida cozida, assada ou na forma de doces. A sua cocção pode levar à transformações físico-químicas alterando as propriedades nutricionais. O objetivo deste trabalho foi avaliar as características físico-químicas, compostos bioativos e atividade antioxidante de doze genótipos de batata-doce, de coloração de polpa variada, na forma in natura e assada. Foram determinados sólidos solúveis totais, acidez, açúcares, carotenoides, antocianinas, compostos fenólicos e atividade antioxidante nos seguintes genótipos de batatas-doces: polpa creme (Rubissol, Cuia, ILS03, ILS10, ILS12, ILS24 e ILS44); polpa laranja (Amélia e Beauregard) e polpa roxa (ILS56, ILS16 e ILS71). Quanto aos resultados foi observada ampla variação entre os genótipos de batata-doce, para todos os parâmetros analisados, em ambas as formas de preparo. A atividade antioxidante foi um parâmetro que demonstrou grande variação entre os genótipos, de 210,29 a 7870,57µg de equivalente trolox/g nos genótipos in natura e de 673,26 a 17306,22µg de equivalente trolox/g nos genótipos assados. Foi observado que em batatas-doces assadas os sólidos solúveis, acidez, açúcares e os compostos bioativos, com exceção dos carotenoides, tenderam a ser concentrados, elevando também a atividade antioxidante total. Em conclusão, o genótipo e a coloração da batata-doce foram parâmetros que exerceram influência sob a sua composição química. Cultivares como Amélia e Beauregard se destacaram pela quantidade de sólidos solúveis totais e carotenoides, respectivamente. Como fonte de antocianinas, as seleções ILS 16 e ILS 56 são recomendadas. O processo térmico influenciou a concentração de compostos antioxidantes e alterou algumas características físico-químicas.