Ana Carolina da Silva

Physicochemical characterisation and radical-scavenging activity of Cucurbitaceae seed oils

Oils extracted from Cucurbitaceae seeds were characterised for their fatty acid and tocopherol compositions. In addition, some physicochemical characteristics, total phenolic contents and the radical-scavenging activities were determined. Oil content amounted to 23.9% and 27.1% in melon and watermelon seeds, respectively. Physicochemical characteristics were similar to those of other edible oils and the oils showed significant antioxidant activities. Fatty acid composition showed total unsaturated fatty acid content of 85.2–83.5%, with linoleic acid being the dominant fatty acid (62.4–72.5%), followed by oleic acid (10.8–22.7%) and palmitic acid (9.2–9.8%). The oils, especially watermelon seed oil, showed high total tocopherol and phenolic contents. The γ-tocopherol was the predominant tocopherol in both oils representing 90.9 and 95.6% of the total tocopherols in melon and watermelon seed oils, respectively. The potential utilisation of melon and watermelon seed oils as a raw material for food, chemical and pharmaceutical industries appears to be favourable.

Utilização de extrato de cogumelo como antioxidante natural em óleo vegetal

Conduziu-se este trabalho, com o objetivo de avaliar a atividade antioxidante de diferentes extratos de cogumelo Agaricus blazei, bem como a estabilidade oxidativa do oleo de soja adicionado de extrato de cogumelo. O cogumelo seco em estufa a 55oC e triturado (10 g) fui submetido a extracao, a temperatura ambiente, com 100 mL de metanol e metanol:agua (1:1) com duracao de 6 e 12 horas para ambas as extracoes. O extrato de maior atividade antioxidante, conforme o metodo DPPH, foi aplicado em oleo de soja na concentracao de 0,1% de compostos fenolicos totais e, entao, submetido ao metodo do Rancimat e ao teste acelerado em estufa a 60oC por um periodo de 16 dias. Amostras de oleo foram retiradas da estufa cada 4 dias e analisadas quanto ao indice de peroxidos e dienos conjugados. Como parâmetros de comparacao, foram utilizados os antioxidantes sinteticos BHT (100 mg/kg), TBHQ (50 mg/kg) e o oleo de soja isento de antioxidantes (controle). Os resultados demonstraram que o extrato metanolico:aquoso, com 6 horas de extracao, apresentou maior atividade antioxidante. A aplicacao desse extrato em oleo de soja proporcionou a seguinte ordem em relacao a estabilidade oxidativa: TBHQ > extrato de cogumelo > BHT = oleo de soja (controle). O extrato de cogumelo tambem foi eficiente em relacao a formacao de peroxidos e dienos conjugados que, apesar de aumentarem ao longo do tempo, foi menor que o BHT, porem maior que o TBHQ. O extrato de cogumelo apresentou-se efetivo na protecao do oleo, podendo ser considerado um potencial antioxidante natural.

Antioxidant activity of oils extracted from orange (Citrus sinensis) seeds

Due to the increasing production of food in the world with consequent increase of the production of waste, the importance of developing researches for its use is noticed. Thus, the interest in vegetable oils with bioactive compounds, such as the ones extracted from fruit seeds, is growing. Therefore, the present study aims to characterize the oils extracted from seeds of Hamlin, Natal, Pera-rio and Valencia orange varieties (Citrus sinensis), as to the levels of total carotenoids, total phenolic compounds, tocopherols and phytosterols, as well as to determine their antioxidant activity. The orange seed oils presented important content of total carotenoids (19.01 mg/kg), total phenolic compounds (4.43 g/kg), α-tocopherol (135.65 mg/kg) and phytosterols (1304.2 mg/kg). The antioxidant activity ranged from 56.0% (Natal) to 70.2% (Pera-rio). According to the results it is possible to conclude that the orange seed oils can be used as specialty oils in diet, since they contain considerable amounts of bioactive compounds and antioxidants.

Cogumelos: compostos bioativos e propriedades antioxidantes

Os transtornos alimentares sao desvios do comportamento alimentar que podem levar a caquexia e a obesidade, entre outros problemas fisicos, os quais se destacam: a osteoporose, a desnutricao grave e a arritmia cardiaca. Dentre os principais tipos de transtornos alimentares existentes temos a anorexia e a bulimia nervosas. Essas duas patologias nas ultimas decadas tem tido incidencia aumentada de forma alarmante e vem representando na atualidade importante causa de mobimortalidade que requer intervencao terapeutica multiprofissional. Nesse contexto, o presente estudo tem por objetivo realizar revisao de literatura sobre a anorexia e bulimia nervosas, dando enfase ao papel da enfermagem. A literatura pesquisada permitiu a constatacao de que e de fundamental importância que o enfermeiro possua conhecimentos sobre esses transtornos, e que esse profissional esteja preparado para orientar e realizar acompanhamento clinico de qualidade e eficiencia para os doentes e seus familiares, com enfase na criacao de vinculos de confianca, apoio emocional e em orientacoes sobre a patologia e suas consequencias para o organismo.

Oxidative stability of soybean oil added to Lentinus edodes and Agaricus blazei mushrooms extracts in an accelerated storage test

Purpose – The purpose of this paper is to evaluate the oxidative stability of soybean oil added by Lentinus edodes and Agaricus blezei extracts in accelerated storage test.Design/methodology/approach – The following treatments were subjected to accelerated storage test in an oven at 60°C for 15 days: Control (soybean oil without antioxidants), TBHQ (soybean oil+100 mg/kg of TBHQ), BHT (soybean oil+100 mg/kg of BHT), L. edodes (soybean oil+3,500 mg/kg of L. edodes extract) and A. blazei (soybean oil+3,500 mg/kg of A. blazei extract). The samples were taken every three days and analyzed for peroxide values and conjugated dienes.Findings – At the end of 15 days, the treatments TBHQ, A. blazei, L. edodes, Control and BHT showed 6.47, 8.81, 41.53, 71.28 and 78.40 meq/kg, respectively, for peroxide values and 0.37, 0.40, 0.67, 1.07 and 1.00 per cent, respectively, for conjugated dienes.Originality/value – The research indicates that mushrooms may be a promising source of natural antioxidants. Therefore, natural...

First record of Tuxophorus caligodes (Siphonostomatoida, Tuxophoridae) in sea-farmed cobia, Rachycentron canadum, in Brazil

The cobia is the only representative of the Rachycentridae family and, because of its zootechnical qualities, production of this fish has been implemented in several countries, such as the United States, Mexico and Brazil. Tuxophorus caligodes is a widespread parasite of marine fish worldwide. For the present report, 15 juvenile cobias were collected from net cages on a fish farm in Ilhabela, state of São Paulo, Brazil, in the winter of 2011. The fish were sacrificed by means of cerebral concussion, and then weighed (280 ± 70.5 g) and measured (27 ± 1.97 cm). After external examination under a stereomicroscope, ectoparasites present on the body surface were collected, fixed and processed for identification. Out of the 15 fish examined, two were parasitized with Tuxophorus caligodes, thus indicating a prevalence of 13.3%. This is the first report of Tuxophorus caligodes in cobias in Brazil.