The environmental impact of the raw effluent and the reaction
samples was inferred by luminescence techniques based on the
light inhibition of marine bacteria Vibrio fischeri after their
contact for 15 min at 15 °C with several dilutions of the
wastewater (ISO DIS 11348) using the commercial apparatus
LUMIStox (Dr. Lange GmbH, Berlin, Germany). The effective
concentration that provokes the inhibition of 20% and 50% of
the microorganisms population (EC20 and EC50, respectively)
was thus attained. pH was determined using a Crison micropH
2000.