Cristiane da Silva Paula

Avaliação do potencial antioxidante frente à oxidação lipídica e da toxicidade preliminar do extrato e frações obtidas das frondes de Dicksonia sellowiana (Presl.) Hook

The species Dicksonia sellowiana, popularly known as tree fern, are a natural fern from American continent found in the Atlantic Forest in Brazil. In 2001 it was added to the list of IBAMA as endangered species due to its exploitation for pots craft for gardening species. This paper describes the antioxidant lipid potential (TBARS and System β-carotene / linoleic acid) of the crude extract and fractions obtained by Soxhlet apparatus of Dicksonia sellowianafronds, besides the cytotoxic and hemolytic activity in vitro. By the TBARS method, all samples tested showed activity, particularly the fraction ethyl acetate and the crude extract whose activity was comparable to standard ascorbic acid. In the system β-carotene / linoleic acid, the fraction of ethyl acetate and crude extract inhibited the oxidation of linoleic acid, especially the ethyl acetate fraction which did not differ statistically from the standard BHT. In a preliminary assessment of toxicity,cytotoxic and hemolytic activity of crude extracts and fractions in the tested models were not observed. The results of this study indicate the antioxidant potential of this plant species in models of inhibiting lipid oxidation without producing toxicity.

Phytochemical and Antinociceptive, Anti-Inflammatory, and Antioxidant Studies of Smilax larvata (Smilacaceae)

The tea of aerial parts of Smilax larvata Griseb. (Smilacaceae) has been ethnopharmacologically used in Southern Brazil due to its anti-inflammatory action. In this study, ethanolic and organic extracts from aerial parts of S. larvata were phytochemically and pharmacologically characterized. The phytochemical analysis of EtOAc extract of S. larvata revealed the presence of three flavonoids, drabanemoroside, kaempferol 3-O-α-L-rhamnopyranosyl(1→2)-α-L-rhamnopyranoside, and kaempferol, the first two being isolated for the first time in this genus, two phenolic compounds p-hydroxybenzoic acid and p-coumaric acid, and alkaloids. In vitro assays demonstrated a potential antioxidant property of SLG. The treatment with SLG induced a significant reduction of the formalin-evoked flinches in rats, an effect reversed by opioid antagonist naloxone. Treatment with SLG also induced a significant increase in the hot plate latency and a decrease of intestinal motility by 45%. No effect was observed over nociceptive responses induced by a TRPA1 agonist mustard oil or over acetic acid-induced writhing in mice. Together, our data suggested that SLG has an in vivo antinociceptive effect, which seems to be associated with the opioid system activation. These findings support previous claims of medical use of Smilax larvata in the treatment of pain conditions.

Atividade antioxidante e toxicidade preliminar do extrato e frações obtidas das folhas e cascas do caule de Dasyphyllum tomentosum (Spreng.) Cabrera

ABSTRACT: Antioxidant activity and preliminary toxicity of the extracts and fractions obtained from the leaves and stem bark of Dasyphyllum tomentosum (Spreng.) Cabrera. Dasyphyllum tomentosum (Spreng.) Cabrera, which belongs to the Asteraceae family, is well known for having many species with therapeutic properties. The aim of this study was to evaluate the extracts and fractions from the leaves and stem bark of D. tomentosum with respect to the antioxidant, cytotoxic and hemolytic activity in in vitro tests. All samples showed antioxidant activity by the DPPH inhibition method, especially the ethyl acetate fraction obtained from the leaves, whose activity was comparable to that of standard ascorbic acid and rutin. Regarding the reduction of the phosphomolybdenum complex, we noted that this same fraction was only similar to rutin and the fraction obtained from the stem bark showed superior results. There was no cytotoxicity and hemolytic activity compared to the models used in the extracts and fractions. The results demonstrate the antioxidant potential of the species without showing toxicity.

Analgesic, Anti-Inflammatory, and Antioxidant Activities of Byrsonima duckeana W. R. Anderson (Malpighiaceae)

Background. Byrsonima is a promising neotropical genus, rich in flavonoids and triterpenes, with several proven pharmacological properties. Nevertheless, Byrsonima duckeana W. R. Anderson is an Amazonian species almost not studied. Objective. To assess the antioxidant, anti-inflammatory, and analgesic activities of Byrsonima duckeana leaves. Materials and Methods. We analyzed an ethanol extract and its fractions for polyphenol content and UHPLC-MS/MS, phosphomolybdenum, DPPH, TBARS antioxidant tests, formalin-induced pain, carrageenan-induced peritonitis, acetic acid-induced abdominal writhings, and hot plate assays. Results. All the samples showed high polyphenol content and antioxidant capacity in the phosphomolybdenum, DPPH, and TBARS tests. We identified ethyl gallate, quinic acid, gallic acid, catechin, epicatechin, quercetrin, and quercetin in the samples. B. duckeana was able to reduce leukocyte migration in the carrageenan-induced peritonitis by 43% and the licking time in the formalin test by 57%. In the acetic acid-induced writhing test, the chloroform (FCL) and ethyl acetate (FEA) fractions were the most active samples. FEA was selected for the hot plate test, where all the dosages tested (5, 50, and 200 mg·kg−1) showed significant analgesic activity. Conclusion. B. duckeana has interesting analgesic and antioxidant activities, due to its high phenolic content, especially phenolic acids.

Efeito de diferentes técnicas extrativas no rendimento, atividade antioxidante, doseamentos totais e no perfil por clae-dad de dicksonia sellowiana (presl.). Hook, dicksoniaceae

The species Dicksonia sellowiana, popularly known as xaxim, is a fern native to the Americas and found in Brazil in the Atlantic Forest. In 2001, its use for making gardening pots was banned, and it was added to the IBAMA [Brazilian Institute of the Environment and Renewable Natural Resources] list as an endangered species. This paper describes the effect of different extraction techniques – including ultrasound, turbolysis, maceration, infusion, decoction, and soxhlet using ethanol and 70% hydroalcoholic solvent on its physical and chemical aspects. The yield of each extraction was evaluated, as well as the profile by HPLC-DAD, the polyphenol content, flavonoids, proanthocyanidins, and steroids, in addition to the antioxidant activities through the DPPH and phosphomolybdenum complex reduction methods. The data were statistically analyzed through standard deviation, Tukey, and PCA. The results showed that the soxhlet extraction using both solvents had the highest overall yield; however, the yield is not directly related to the increase in total bioactive content and antioxidant activities. Extractions by decoction and turbolysis using a hydroalcoholic solvent exhibited the best results in total content and antioxidant activity – results that are evident when evaluated through PCA, demonstrating that this solvent and these extractions are the most selective in the proposed study.

Estudo do potencial fitotóxico de extratos de Bauhinia ungulata L. sobre a divisão celular e atividade enzimática em plântulas de alface

Theaim of this studywas to evaluate thephytotoxic actionofextractand fractionsobtainedfrom the leaves ofBauhiniaungulata L. inbioassaylaboratory, assessing their interferenceon cell division andactivity of the enzymesalpha-amylase, catalase, peroxidase andpolyphenoloxidaseofLactucasativa(lettuce). The lettuce seedswere exposedto concentrationsof 250,500and 1000μg.mL-1of theextracts and fractions of Bauhinia ungulataunder controlled environmental conditions. After three days ofrootradicleprotrusion, the plants` rootswere cutand subjected tospecific preparationfor visualization andcounting of the number ofcells in eachmitotic stage. On the seventh daythe sampleswere subjected toenzymatic activityusingspecific techniquefor eachenzyme anda spectrophotometer measure. In the analysisof the mitotic indexit was observedthatthere was reduction in the number of cells in mitosis in the roots of the plants tested and thattheethyl acetate fractionsignificantly affected thecell division. The effecton the enzymesthat showed changesinthe antioxidant defensesystemof Lactucasativaindicate thatthe crude extractand the fractionsaltered theproductionofα-amylase, peroxides, catalaseand polyphenol enzymesin at least oneof the testedconcentrations, representingan indicationstress,which interferesin the celldivision.Theobtained results point out the presence ofcompoundswithinhibitoryorstimulatory activityon plant leaves of B. ungulata,revealingphytotoxic potentialtolettuce seedlings.

Residues of Citrus sinensis (L.) Osbeck as agents that cause a change in antioxidant defense in plants

This work aimed to verify the allelopathic potential of the extract of Citrus seeds, for the purpose of adding a sustainable value to the fruit seeds toward their use as industrial residues. The extract was obtained with a Soxhlet apparatus by using hexane, chloroform, and methanol as solvents. The hexane extract of the Citrus seeds primarily consisted of linoleic acid (36.6%), followed by α-linoleic acid (25.3%), oleic acid (17.8%), palmitic acid (9.7%), and estearic acid (3.3%). The analysis results indicate that the oil is similar to those used in the cosmetics and food industries and has an economic value from its industrial application. In addition, the use of the oil causes changes in the oxidant balance, germination, and growth of plants.