Análise parasitológica em hortaliças cultivadas em diferentes sistemas de produção

Abstract

The consumption of green-leafy vegetables has been incentivized given the scientific data showing the presence of nutritional characteristics associated with human health benefits. Notwithstanding the microbiological quality in green leafy vegetables has generated interest in preoccupation in researchers seeing that they transmit pathogens to humans, especially parasitical agents of zoonotic importance. The present study analyses the parasitological contamination in curly lettuce (Lactuca sativa) cultivated in different production systems (conventional, organic and hydroponic) supplied for a family garden co-operative, in Presidente Prudente, São Paulo. The harvests of collection were repeated at weekly intervals, during a period of five months, yielding 180 samples. The lettuce were washed with Extran MA 02 a 0.5% and the resulting fluid submitted to centrifuge-sedimentation and flotation techniques, in order to recover the parasites structures. Contamination enteroparasites was observed in all production systems, although more frequently in vegetables grown in hydroponic system. It was observed that 71 (39.4%) samples were contaminated with at least one parasitic structure: 34 (18.9%) of lettuce grown in the hydroponic, 20 (11.1%) in the organic and 17 (9.4%) in the conventional system. Cysts of Entamoeba spp. were the most common parasitic structures in vegetables, and the most cysts counted were those produced in the hydroponic system (p = 0.003). Other parasitic structures were observed less frequently. Eggs or Trichostrongyloid larvae were recovered in lettuce cultivated in the three systems. Strongyloides spp. eggs were found in conventional and organic systems, while a larva in a hydroponic system sample. Considering the results of this present study, the importance of controlling the hygienic and sanitary conditions in the green leafy vegetables can be verified, as well as the adequate sanitation before the raw consumption independently of the system of cultivation.