Garlic (Allium sativum L.) and ready-to-eat garlic products: In vitro antioxidant activity

Garlic contains polyphenol and sulphur compounds, which are responsible for its antioxidant activity (AA). This study aimed at evaluating the AA of fresh garlic and its commercialised products and their shelf life. Fresh garlic (FG) and its products, i.e. chopped with salt (CGS), chopped without Salt (CG), fried (FRG) and mixed garlic (FG with dehydrated garlic; MG) antioxidant activity was evaluated by three different methods: DPPH (1,1-diphenyl-2-picrylhydrazyl) assay, beta-carotene/linoleic acid assay and Rancimat method. Amongst all the analysed products, fried garlic presented the highest antioxidant activity. The free radical-scavenging activity decreased during the shelf life of all analysed products that correlated with the decrease in the total polyphenol content. Our findings suggest that some compounds other than phenol may have contributed towards this outcome. (c) 2008 Elsevier Ltd. All rights reserved.

Total phenolic content and free radical scavenging activities of methanolic extract powders of tropical fruit residues

Methanolic extract powders of acerola, passion fruit and pineapple industrial residues, including pulp, seeds and peel, altogether (except for acerola) devoid of seeds, were screened for antioxidant capacity. The total phenolic contents (TPCs) of the extract powders were compared with their radical-scavenging activities (RSA) against both DPPH(center dot) and superoxide anion (O(2)(center dot-)) radicals, and their protective effect against liposome peroxidation, triggered by peroxyl radical. Lipid peroxidation was followed by the fluorescence decay of the probe, 4,4-difluoro-5-(4-phenyl-1,3-butadienyl)-4-bora-3a,4a-diaza-s-indacene-3-undecanoic acid (C(11)-BODIPY(581/591)). The TPCs of acerola, passion fruit and pineapple extract powders were (94.6 +/- 7.4); (41.2 +/- 4.2) and (9.1 +/- 1.3) mg of gallic acid equivalents g(-1) of dry extract, respectively. Acerola showed the best RSA-DPPH(center dot) scores, whereas passion fruit was more protective on the RSA-O(2)(center dot-) system. Together with the protective effects against lipid peroxidation (rate of BODIPY decay) which, were similar for acerola and passion fruit extracts, these data suggest that the methanolic extracts of acerola and passion fruit residues may be useful as antioxidant supplements, particularly the acerola extract, due to its high phenolic content. (C) 2008 Elsevier Ltd. All rights reserved

Free radical scavenging profile and myeloperoxidase inhibition of extracts from antidiabetic plants: Bauhinia forficata and Cissus sicyoides

There is abundant evidence that reactive oxygen species are implicated in several physiological and pathological processes. To protect biological targets from oxidative damage. antioxidants must react with radicals and other reactive species faster than biological substrates do. The aim of the present study was to determine the in vitro antioxidant activity of aqueous extracts from leaves of Bauhinia forficata Link (Fabaceae - Caesalpinioideae) and Cissus sicyoides L. (Vitaceae) (two medicinal plants used popularly in the control of diabetes mellitus), using several different assay systems, namely, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) decolorization. superoxide anion radical (O-2 center dot-) scavenging and myeloperoxidase (MPO) activity. In the ABTS assay for total antioxidant activity, B. forficata showed IC50 8.00 +/- 0.07 mu g/mL, while C. sicyoides showed IC50 13.0 +/- 0.2 mu g/mL. However, the extract of C. sicyoides had a stronger effect on O-2 center dot- (IC50 60.0 +/- 2.3 mu p/mL) than the extract of B. forficata (IC50 90.0 +/- 4.4 mu g/mL). B. forficata also had a stronger inhibitory effect on MPO activity, as measured by guaiacol oxidation, than C. sicyoides. These results indicate that aqueous extracts of leaves of B. forficata and C. sicyoides are a potential source of natural antioxidants and may be helpful in the prevention of diabetic complications associated with oxidative stress.

Phytochemicals and Antioxidant Activity of Citrus Seed Oils

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Antioxidant activity, ascorbic acid and total phenol of exotic fruits occurring in Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Iron chelating-mediated antioxidant activity of Plectranthus barbatus extract on mitochondria

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Quercetin-PVP K25 solid dispersions: Preparation, thermal characterization and antioxidant activity

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Chemical composition and antioxidant activity of dried powder formulations of Agaricus blazei and Lentinus edodes

Several mushroom species have been pointed out as sources of antioxidant compounds, in addition to their important nutritional value. Agaricus blazei and Lentinus edodes are among the most studied species all over the world, but those studies focused on their fruiting bodies instead of other presentations, such as powdered preparations, used as supplements. In the present work the chemical composition (nutrients and bioactive compounds) and antioxidant activity (free radical scavenging activity, reducing power and lipid peroxidation inhibition) of dried powder formulations of the mentioned mushroom species (APF and LPF, respectively) were evaluated. Powder formulations of both species revealed the presence of essential nutrients, such as proteins, carbohydrates and unsaturated fatty acids. Furthermore, they present a low fat content (<2 g/100 g) and can be used in low-calorie diets, just like the mushrooms fruiting bodies. APF showed higher antioxidant activity and higher content of tocopherols and phenolic compounds (124 and 770 μg/100 g, respectively) than LPF (32 and 690 μg/100 g). Both formulations could be used as antioxidant sources to prevent diseases related to oxidative stress. © 2012 Elsevier Ltd. All rights reserved.

In vivo analgesic activity, toxicity and phytochemical screening of the hydroalcoholic extract from the leaves of Psidium cattleianum Sabine

Ethnopharmacological relevance: Psidium cattleianum Sabine is extensively used in Brazilian traditional medicine to treat several diseases including painful disorders. Aim of the study to investigate the toxicity and the possible analgesic activities of the hydroalcoholic extract from the leaves of Psidium cattleianum Sabine (ELPCS), to support its use in folk medicine. To screen the major phytochemical constituents of this extract and evaluate their antioxidant activity. Materials and methods: ELPCS was assessed for its antioxidant activity using the DPPH model. Its analgesic activity was examined using mouse models of acetic acid-induced writhing and hot plate paw licking models. The major phytochemical constituents of the extract were screened; their toxicity on LLC-MK2 mammalian cells was evaluated. Results: ELPCS exhibited significant peripheral analgesic activity at doses of 60, 80, 100, 200 and 400 mg/kg in mice, but it did not display central analgesic activity and not was toxic to LLC-MK2 cell (LD 50>400 μg/mL). The extract exhibited free radical scavenging activity as evidenced by IC 50 values (15.9 μg/mL) obtained by the DPPH method. Phytochemical screening detected flavonoids, saponins, cardiac glycosides, anthraquinones, and tannins. Conclusions: The results of the experimental studies proved the analgesic activity of ELPCS and supported the traditional use of this plant. © 2013 Elsevier B.V. All rights reserved.

Antioxidant capacity and larvicidal activity of essential oil and extracts from Lippia grandis

The leaves and thin branches of Lippia grandis Schauer, Verbenaceae, are used for flavoring of food in the Brazilian Amazon, as substitute for oregano. In this study the constituents of the essential oil were identified and the antioxidant capacity and larvicidal activity of the oil and methanol extract and its sub-fractions were evaluated. A sensory evaluation was determined in view of absence of toxicity. The oil showed a yield of 2.1% and its main constituents were thymol (45.8%), p-cymene (14.3%), γ-terpinene (10.5%), carvacrol (9.9%) and thymol methyl ether (4.8%), totalizing 85%. The DPPH radical scavenging activity showed values for the EC50 between 9.0 and 130.5 µg mL^-1 and the TEAC/ABTS values varied from 131.1 to 336.0 mg TE/g, indicating significant antioxidant activity for the plant. The total phenolic content ranged from 223.0 to 761.4 mg GAE/g, contributing to the antioxidant activity observed. The crude extracts inhibited the bleaching of β-carotene and the oil showed the greatest inhibition (42.5%). The oil (LgO, 7.6±2.4 µg mL^-1) showed strong larvicidal activity against the brine shrimp bioassay. The sensory evaluation was highly satisfactory in comparison to oregano. The results are very promising for the use of L. grandis in seasoning and antioxidant products.

Antioxidant capacity and biological activity of essential oil and methanol extract of Conobea scoparioides (Cham. & Schltdl.) Benth

Os óleos essenciais da planta sub-aquática Conobea scoparioides (fresca e previamente seca) apresentaram rendimentos de 3,4 e 3,3%, respectivamente. Os principais constituintes identificados foram o éter metílico do timol (39,6 e 47,7%), timol (40,0 e 26,4%), α-felandreno (12,1 e 14,3%) e p-cimeno (1,5 e 1,7%), totalizando mais de 90% nos referidos óleos. A concentração de seqüestro do radical DPPH (CE50) dos óleos e extrato foi de 46,7 ± 3,6 µg mL^-1 para a planta fresca (CsO-f), de 56,1 ± 2,4 µg mL^-1 para a planta seca (CsO-d), e de 23,0 ± 2,2 µg mL^-1 para o extrato metanólico (CsE-d). O valor do extrato é comparável ao BHT (19,8 ± 0,5 µg mL^-1), usado como padrão antioxidante. O valor médio dos óleos é duas vezes menor, mas igualmente importante como agente antioxidante. O teor de Fenólicos Totais (TP, 124,6 ± 8,7 mg GAE per g) e o Trolox Equivalente (TEAC, 144,1 ± 4,9 mg TE per g) do extrato metanólico confirmaram a significativa atividade antioxidante de C. scoparioides. Da mesma forma, nos bioensaios com larva de camarão (Artemia salina) o valor médio da concentração letal dos óleos (CL₅₀, 7,7 ± 0,3 µg mL^-1) foi dez vezes maior que no extrato metanólico (CL₅₀, 77,6 ± 7,1 µg mL^-1) mostrando importante atividade biológica.

Antioxidant capacity and biological activity of essential oil and methanol extract of Hyptis crenata Pohl ex Benth

O óleo essencial das folhas e ramos finos frescos e secos de Hyptis crenata forneceu os seguintes rendimentos, 1,4% e 0,9%. Os constituintes voláteis principais foram α-pineno (22,0%; 19,5%), 1,8-cineol (17,6%; 23,2%), β-pineno (17,0%: 13,8%), cânfora (4,7%; 11,6%), limoneno (5,4%; 4,4%) e γ-terpineno (3,5%; 2,4%), totalizando mais de 70% nos óleos. A atividade de seqüestro do radical DPPH para o extrato metanólico (CE₅₀, 16,7 + 0,4 µg/mL) foi comparável ao do BHT (19,8 ± 0,5 µg/mL) mostrando uma significante atividade antioxidante. Os óleos apresentaram baixa atividade. O teor de fenólicos totais (TP, 373,0 + 15,9 mg GAE/g) e equivalente trolox (TEAC, 226,8 + 0,5 mg TE/g) confirmaram a atividade antioxidante do extrato metanólico, que pode ser atribuída à presença de compostos fenólicos polares. No teste com larvas de camarão as concentrações letais para o óleo e extrato metanólico foram 6,7 + 0,2 µg/mL e 13,0 + 3,7 µg/mL, respectivamente, fornecendo importante evidência de suas atividade biológicas.

Phytochemical characterization, antimicrobial activity, and antioxidant potential of Equisetum hyemale L. (Equisetaceae) extracts

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Comparation of free radical scavenger activity between seven species of Passiflora L.

Antioxidant capacities of seven species of Passiflora were evaluated through comparation of the free radical DPPH scavenging activity. The studied species included cultivated and traditionally used P. edulis, P. incarnata and P. alata and less common species P. coccinea, P. laurifolia, P. mucronata and P. gardneri. The experimental design was completely randomized with ANOVA and Tukey test as main statistical analyses. The results showed that species of Passiflora had variable antioxidant capacities, ranging from 28 to 95% of free radical DPPH scavenging activity.

Analysis of Passion Fruit rinds (Passiflora edulis): Isoorientin quantification by hptlc and evaluation of antioxidant (radical scavenging) capacity

The content of isoorientin in passion fruit rinds (Passiflora Mulls fo. flavicarpa O. Degener) was determined by HPTLC (high performance thin layer chromatography) with densitometric analysis. The results revealed a higher amount of isoorientin in healthy rinds of P edulis (92.275 +/- 0.610 mg L-1) than in rinds with typical symptoms of PWV (Passion fruit Woodiness Virus) infection (28.931 +/- 0.346 mg L-1). The HPTLC data, allied to assays of radical scavenging activity, suggest the potential of P Mulls rinds as a natural source of flavonoids or as a possible functional food.