Changes in the medicinal and antimicrobial compounds, methyl palmitate, methyl stearate, and bis (2-ethylhexyl) phthalate in American agave (Agave Americana L. cv Marginata) under urea treatment

In the present study, the effect of urea fertilizer under pot and greenhouse cultivation on growth rate, total content of leaf terpenoids and bioactive compounds detectable by GC-MS was investigated in American agave leaf extract. Urea 46% fertilizer, with two concentrations of 5 and 10 g / l was used for irrigation, in 8-leaf stage and their effects were compared with plants irrigated with no fertilizer as control in a randomized complete block design. Addition of urea fertilizer with both concentrations increased the fresh and dry weight of leaves and roots. Urea fertilizer had no significant effect on leaf terpenoid content, but in terms of leaf extract analysis by GC-MS, had a positive effect on increasing the content of methyl palmitate and methyl stearate, which are valuable medicinal compounds with antimicrobial, anti-inflammatory, anti-cancer, and antioxidant properties. Utilization of urea fertilizer, doubled the percentage of these compounds in leaf extract. However, urea fertilizer reduced the content of bis(2-ethylhexyl) phthalate, which has also medicinal properties comparable to the two above mentioned compounds. The positive effect of urea fertilizer on a significant increase in octadecane and methyl palmitate (about twice) with usability as a biofuel is another important result of the present work.