RESUMO A semente de Moringa oleifera é composta por proteínas catiônicas, podendo ser aplicada como eficiente coagulante na clarificação de águas para consumo humano. Objetivou-se identificar o melhor método de preparação de Moringa oleifera, o melhor tempo para sedimentação e a concentração ótima para diferentes valores de turbidez bruta. Para concentrações de 100 a 500 mg L-1, a semente foi descascada, triturada, peneirada e diluída (método 1); secada, triturada, peneirada, diluída e filtrada (método 2); triturada, peneirada, diluída e filtrada (método 3). Os ensaios de Jartest foram realizados em triplicata para cada método, em águas com turbidez de 20, 40, 60, 80 e 100 UNT e a cinética de sedimentação para 30, 60, 90 e 150 min. Não houve diferenças significativas na remoção de turbidez entre os métodos de preparo pelos testes F e t de Student. No entanto, a filtração pode evitar incrustrações e incremento de matéria orgânica à água tratada (método 3). A adição de Moringa oleifera produz eficiente remoção de turbidez em águas acima de 40 UNT. O tempo máximo para sedimentação foi de 129,6 min, para remoção de turbidez em 90,5%.

ABSTRACT Moringa oleifera seeds comprise cationic proteins and can be used as efficient coagulant in the clarification of water for human consumption. The objective was to identify the best method of preparation of Moringa oleifera, the best time to sedimentation and the optimum concentration for different values of affluent turbidity. For concentrations of 100 to 500 mg L-1, seed was peeled, crushed, sieved and diluted (method 1); dried, crushed, sieved, diluted and filtered (method 2); crushed, sieved, diluted and filtered (method 3). The Jartest assays were performed in triplicate for each method in water with turbidity of 20, 40, 60, 80 and 100 NTU and sedimentation kinetics to 30, 60, 90 and 150 min. There were no significant differences in turbidity between the methods after F test and Student’s t-test. However, the filter can prevent fouling and increase of organic matter to treated water. The use of Moringa oleifera produces efficient decrease in turbidity in waters above 40 NTU. The maximum time for sedimentation was 129.6 min, to 90.5% remove of turbidity.

Actualmente municipios de la Costa Atlántica Colombiana no cuentan con suministro de agua potable. La aplicación artesanal de la Tuna (Opuntia ficus-indica) como coagulante es una práctica tradicional en comunidades rurales. En esta investigación se realiza la caracterización del tallo de la Tuna que crece de manera silvestre en el departamento de Bolívar, y del polvo extraído de esta planta, con el fin de identificar componentes asociados a su poder coagulante para la remoción de turbidez y de color en aguas crudas. Las pencas de la planta se sometieron a operaciones de corte, pelado, secado, molienda, tamizado y despigmentado para obtener el coagulante. El rendimiento del proceso global fue de 65g de coagulante/Kg de material vegetal. Los resultados indicaron que la penca contiene alto porcentaje de humedad y pequeñas proporciones de saponinas, flavonoides, sales minerales de calcio y hierro; lo cual permitió concluir que estos metabolitos y sales no son los responsables de su poder coagulante debido a las cantidades poco significativas en las que se encuentran. Se consideró que otras especies química tales como el ácido poligalacturónico y compuestos algínicos son realmente los que le confieran la cualidad al biomaterial. También, se evaluó el poder coagulante del material extraído, se analizó el efecto de tres dosis sobre el color, la turbidez y el pH del agua tratada. Los resultados indicaron que tiene la capacidad de remover 50% del color y 70% de turbidez de aguas crudas con alta turbidez inicial, y que no altera significativamente su pH.

Currently, municipalities in the Colombian Atlantic Coast do not have potable water supply. The implementation of the Tuna as a coagulant is a traditional practice in rural communities, but is used in craft way. In the present investigation, the characterization of the stalk of Tuna (Opuntia ficus-indica) growing in the wild in the Bolivar department, and of the powder extracted from this plant was realized with the purpose to identify components associated with its coagulant power to remove color and turbidity in raw water. The stalks of this plant were subjected to cutting, peeling, drying, grinding, sieving and depigment for obtaining the coagulant. The overall process yield was 65g of coagulant/kg of vegetal material. The results also indicated that the stalk of Tuna contains high moisture content and low amounts of saponins, flavonoids, minerals, calcium and iron. It allowed concluding that these metabolites and salts are not responsible of the coagulant power of plant due to the insignificant amounts in which they are present. Therefore, it is presumed that other chemical species such as polygalacturonic acid and alginic compounds are those that confer the quality to the biomaterial. Also, the coagulant power of extracted material was evaluated. The effect of three dosis on the color, turbidity and pH of trated water was analized. The results indicated that it has the capacity to remove 50% of color and 70% of turbity from crude water with high initial turbidity. Also, it does not affect significantly its pH.