Essential oil and linalool contents in basil (Ocimum basilicum) irrigated with reclaimed water

Essential oils (EO) are volatile compounds with complex chemical compositions that are derived from the secondary metabolism of aromatic herbs. There are several applications of EO in the industrial and medical sectors. Basil (Ocimum sp.) is one of the most important EO-producing aromatic herbs. In this study, EO content (EOC) and linalool content (LC) in basil irrigated with reclaimed water were investigated. Plant development parameters, nutrient absorption and crude protein (CP) content were also evaluated. The experiment was conducted in a greenhouse, with five different treatments and five repetitions each. Compared with treatments only using water, the results of those with reclaimed water irrigation showed higher nutrient absorption, CP contents (in their foliar tissue), length of plant branches, foliar biomass weights, and EOC and LC. EOC reached up to 0.58% of the dry biomass and LC was up to 5.84% of EO mass. In practice, it is estimated that around 5.8 kg of EO and 0.34 kg of linalool can be obtained from one ton of dry basil biomass. HIGHLIGHTS Higher essential oil and linalool contents were obtained in plants irrigated with higher percentage of reclaimed water used.; Reclaimed water use resulted in the highest length of branches and biomass production of dry leaves, up to 30 cm and 28 g per plant, respectively.; Crude protein content in leaves increased proportionally to the percentage of reclaimed water used.; Approximately 5.8 kg of EO and 0.34 kg of linalool can be obtained per ton of basil dry mass.