Investigation on the in vitro antioxidant capacity of methanol extract, fractions and flavones from Oroxylum indicum Linn bark

ABSTRACT Antioxidants from natural sources hold high values regarding their indispensible roles in the development of nutraceuticals, pharmaceuticals and cosmetic products. Oroxylum indicum L. is a common medicinal plant with a wide range of therapeutic properties, including a notable antioxidant potency that was reported, yet has not been subjected to more detailed studies. The present study evaluated the potency of Oroxylum indicum methanol stem bark extract, along with its hexane, ethyl acetate, methanol fractions, three flavones including baicalein, oroxylin A and chrysin using DPPH assay. In terms of IC50 values, the crude extract (65,48 µg/mL) exhibited moderate inhibitory activity which was as half potent as that of its ethyl acetate fraction (32,94 µg/mL). This fraction was also superior to the methanol and hexane fractions, as their IC50 were 57,19 and 137,95 µg/mL respectively. Remarkably, a yellow powdery sub-fraction consisted of isolated compounds showed powerful activity (32,89 µg/mL) compared to those of its components, revealing the intriguing effect of synergism while giving evidence for the theory of structure-activity relationship between some flavones and their antioxidant capability. Perpetual search for new radical scavenging agents in Oroxylum indicum is emboldened considering its partially exploited potential in this study

Enraizamento de manjericão em diferentes substratos e doses de cinzas / Stem rooting of basil in different substrates and doses of ash

O trabalho teve como objetivo avaliar a influência de doses de cinzas em diferentes substratos no enraizamento de estacas de manjericão (Ocimum basilicum). O experimento foi conduzido em área do Núcleo de Capacitação e Pesquisa da Universidade Federal Rural da Amazônia, em Belém. Foi utilizado o delineamento experimental inteiramente casualizado, em esquema fatorial 2 x 5, constituído pelas combinações entre os fatores substratos (casca de arroz carbonizada e casca de castanha triturada) e acréscimo de cinzas (5 mL e 10 mL de cinza de casca de arroz, 5 mL e 10 mL de cinza de casca de castanha e sem cinza) com 4 repetições. Cada unidade experimental foi constituída por 10 estacas, num total de 400 estacas. Foram avaliadas as características percentual de enraizamento de estacas, número e comprimento de raízes. Não houve interações significativas entre os fatores avaliados (substrato e cinzas). Entre as características avaliadas o substrato casca de arroz carbonizada apresentou diferenças apenas no comprimento da raiz e no número de raízes, enquanto as dosagens de cinzas apresentaram diferenças apenas no percentual de enraizamento. O trabalho permitiu concluir que as dosagens de cinzas apresentaram efeito positivo sobre o enraizamento das estacas de manjericão, assim como o substrato a base de casca de arroz carbonizada propiciou melhores condições para o desenvolvimento das raízes. Assim, a casca de arroz é uma alternativa totalmente viável, pois além de apresentar características apropriadas para o enraizamento também possui baixo custo de aquisição, estando ao alcance de muitos produtores.

The study aimed to evaluate the influence of ash doses on different substrates on the stem rooting of basil (Ocimum basilicum). The experiment was conducted in the area of core training and research at the Universidade Federal Rural da Amazônia, in Belém, used a completely randomized design, factorial scheme 2 x 5 consisting of the combinations of the factors substrate (carbonized rice husk and bark brown ground) and increase ash (5 mL and 10 mL of rice husk ash 5 mL and 10 mL of husk ash and brown bark no gray) with four repetitions. Each experimental unit consisted of 10 cuttings, a total of 400 cuttings. Was evaluated the characteristics percentage of rooting, number and length of roots. There was no significant interaction between the factors evaluated (substrate and ash). Among the characteristics evaluated the carbonized rice showed only differences in root length and root number, while the levels of ash showed only differences in rooting percentage. The study revealed that the dosages of ash had a positive effect on rooting of cuttings of basil, as well as the substrate prepared with rice hulls provided the best conditions for root development. Thus, the rice husk is an alternative, as well as presenting features suitable for rooting also has a low cost of acquisition, being within reach of many producers.

Avaliação da atividade fitotóxica com enfoque alelopático do extrato das cascas de Celtis iguanaea (Jacq. ) Sargent Ulmaceae e purificação de dois triterpenos / Evaluation of the phytotoxic activity focused on the allelopathic effect of the extract from the bark of Celtis iguanaea (Jacq. ) Sargent Ulmaceae and purification of two terpenes

A espécie Celtis iguanaea (Jacq.) Sargent é popularmente conhecida como esporão de galo ou grão de galo. As folhas são indicadas pelo uso popular para o tratamento de dores no corpo e no peito, para reumatismo, asma, cólicas, má digestão e como diurético; as raízes são utilizadas para infecções urinárias e as cascas para a febre. O presente trabalho objetivou contribuir para o estudo fitoquímico e atividade fitotóxica com enfoque alelopático das cascas de Celtis iguanaea. O extrato etanólico foi submetido à partição com os solventes hexano, clorofórmio e acetato de etila. As substâncias friedelina e epifriedelinol (triterpenos) foram isoladas da fração hexano e identificadas por meio de métodos espectroscópicos de RMN de ¹H e 13C. O extrato bruto na concentração de 0,1 mg mL-1 causou inibição acentuada do hipocótilo em 34,97% e estimulou o crescimento da radícula em 29,64% de plântulas de Lactuca sativa. No ensaio de toxicidade frente à Artemia salina o extrato bruto e frações apresentaram uma CL50 superior a 1000 μg mL-1, indicando que o mesmo não possui efeito tóxico.

The species Celtis iguanaea (Jacq.) Sargent is popularly known as "esporão de galo" or "grão de galo". Its leaves are recommended by the popular use for the treatment of body and chest aches, as well as for rheumatism, asthma, cramps, indigestion and as diuretic; its roots are used for urinary infections and its bark for fever. This study aimed to contribute to the phytochemical investigation of the toxic activity focused on the allelopathic effect of the bark of Celtis iguanaea. The ethanol extract was subjected to solvent partition with hexane, chloroform and ethyl acetate. The substances friedelin and epifriedelinol (triterpenes) were isolated from the hexane fraction and identified by spectroscopic methods ¹H and 13C NMR. The crude extract at a concentration of 0.1 mg mL-1 caused marked inhibition of hypocotyl in 34.97% and stimulated radicle growth in 29.64% seedlings of Lactuca sativa. In the toxicity test against Artemia salina the crude extract and fractions showed an LC50 higher than 1000 μg mL-1, indicating that it has no toxic effect.