ABSTRACT The fruits of Litchi chinensis Sonn., Sapindaceae, are renowned for their biological activities. However, their leaves are poorly explored, although they represent an important source of vegetable raw material with biological properties as antioxidant, anti-inflammatory and antinociceptive. An HPLC method was developed and validated for the simultaneous quantification of epicatechin and procyanidin A2 in the leaf hydroethanolic extract of L. chinensis. The markers and other unidentified components were separated on a Luna Phenomenex C18 column (250 mm × 4.6 mm, 5 µm) with mobile phase composed of acetonitrile: water pH 3.0 (with sulfuric acid), in a gradient run; at 1.0 ml min-1, 30 ºC and 278 nm for detection. The method was linear over an epicatechin and procyanidin A2 concentration range of 10–100 µg ml-1. The Limit of Quantification for epicatechin and procyanidin A2 were 1.7 and 2 µg ml-1, respectively. The Relative Standard Deviation (%) values for markers (intra- and inter-day precision studies) were <4.0% and the accuracy was 100 ± 5%. The method was applied to ten samples collected in the state of Santa Catarina (Brazil), which showed 14.8–44.5 and 44.8–69.6 mg g-1 of epicatechin and procyanidin A2, respectively. The proposed method could be a valuable tool for quality assessment of L. chinenis leaves as well as their herbal derivatives.

Um total de 240 tilápias-do-nilo foi examinado entre abril de 2007 e março de 2008, a partir de três diferentes localidades em quatro estações, 20 de cada piscicultura. As pisciculturas estavam localizadas em Joinville, Blumenau e Ituporanga, Estado de Santa Catarina, Brasil. Taxa de prevalência, intensidade média, abundância média e dominância média relativa foram comparadas entre as pisciculturas e entre as estações. Durante esse período, a qualidade da água se manteve em valores normais para tilápia. Piscinoodinium pillulare (Dinoflagellida) foi o mais dominante seguido por Trichodina magna e Trichodina compacta (Ciliophora), Cichlydogyrus sclerosus, Cichlydogyrus halli, Cichlydogyrus thurstonae, Scutogyrus longicornis (Monogenoidea), copepoditos Lernaeidae gen. sp. Os maiores valores de taxa de prevalência, intensidade média e abundância média de ectoparasitos foram encontrados na superfície do corpo de peixes de Joinville, seguidos pelos de Blumenau e Ituporanga. Nas brânquias, as maiores intensidades e abundâncias médias foram encontradas em peixes de Blumenau e Ituporanga examinados no inverno. Piscinoodinium pillulare apresentou prevalência de 100% no outono em Blumenau e Ituporanga. No inverno, a prevalência de P. pillulare ocorreu também em todas as pisciculturas. Peixes de Joinville apresentaram prevalência de 100% de Monogenoidea em todas as estações, assim como as maiores intensidades e abundâncias médias. Os resultados mostraram que a maioria dos peixes examinados apresentaram maiores infestações por protozoários no outono e inverno, e metazoários na primavera e no verão.

A total of 240 Nile tilapia were examined between April 2007 and March 2008, gathered from three different fish farms, 20 fish in each fish farm, in the four seasons of the year. Fish ponds were located in Joinville, Blumenau and Ituporanga, Santa Catarina state, Brazil and each pond had a different culture system. Prevalence, mean intensity, mean abundance and mean relative dominance were compared among fish ponds and seasons. During this period, the water quality was kept in normal values. Piscinoodinium pillulare (Dinoflagellida) was the most dominant parasite followed by Trichodina magna e T. compacta (Ciliophora), Cichlydogyrus sclerosus, C halli, C. thurstonae, Scutogyrus longicornis (Monogenoidea), copepodids Lernaeidae gen. sp. The highest prevalence, mean intensity and mean abundance of ectoparasites were found on the body surface in fish from Joinville followed by Blumenau and Ituporanga. In the gills, the highest mean intensity and mean abundance were found in fish from Blumenau and Ituporanga in the winter. Piscinoodinium pillulare showed prevalence 100% during autumn in Blumenau and Ituporanga. In winter P. pillulare occurred in all study facilities. Fish from Joinville showed 100% prevalence of Monogenoidea during all seasons, as well as the highest mean intensity and abundance. The results showed that the majority of examined fish had higher infestations by protozoan during autumn and winter and higher infestations by metazoan have occurred in spring and summer.