Análise parasitológica e microbiológica de alface (Lactuca Sativa L.) comercializados em São Luís, Maranhão

Abstract

Lettuce (Lactuca sativa Linn) is the most consumed leafy vegetable in the world. And with that, there is a growing concern about the sanitary quality of this food, as this vegetable can be contaminated by pathogenic enterobacteria and parasites arising from its production, handling and exposure during sale. Considering these aspects, the present work aimed to analyze the parasitic forms, total and thermotolerant coliforms and other enterobacteria in lettuce sold in large markets in the city of São Luís, Maranhão, Brazil. The present work is a cross-sectional epidemiological study with a quantitative approach. Lettuce samples were collected in the morning, from sellers of six municipal markets, classified as A, B, C, D, E and F. The sampling unit was the head of curly variety lettuce with the traditional cultivation system. The collected samples were identified, packaged, and subsequently processed. For parasitological evaluation and visualization of helminth eggs and larvae and protozoan cysts, three different methodologies were used (Baermann-Moraes, Hoffman, Pons and Janer and Faust). The quantification of total and thermotolerant coliforms was performed using the multiple tube test, and the result was quantified in Most Probable Number (MPN/g). For the identification of enterobacteria, the Enterokit B® was used. Of the 60 samples collected, 88.33% showed parasitological contamination. The protozoa found were: Balantidium coli (85.00%), Giardia lamblia (30.00%), Entamoeba coli (18.33%), Endolimax nana (8.33%) and Blastocystis hominis (3.33%) and helminths, Hookworms (43.33%), Hymenolepis nana (35.00%), Strongyloides stercoralis (26.66%), Toxocara canis (11.66%), Dipilidium caninum (10.00%), Ascaris lumbricoides (5.00%), Fasciola hepatica (3.33%) and Taenia sp. (1.66%). All lettuce samples showed total and thermotolerant coliforms, and of these, 48.33% were unfit for consumption, following the Resolution of the Collegiate Board No. 12/01 of the National Health Surveillance Agency (ANVISA). About 20.00% of the samples showed contamination by Escherichia coli, which is an important microbiological indicator of fecal contamination. The data obtained from this study demonstrate the occurrence of contaminants present in lettuce sold in the region, and it is recommended that corrective actions be carried out by ANVISA, directed at marketers and producers of this food, to clarify the need to improve cultivation conditions, exposure and commercialization of this food. And with that prevent the population of cases of gastrointestinal infections caused by the ingestion of contaminated vegetables.