RESUMEN
Borage of Boraginaceae family is a valuable medicinal plant. This plant because their seeds contain unsaturated fatty acids is introduced as an important food. Many research has indicated that the borage extract is able to scavenge active oxygen species and DPPH free radical To study the effect of different levels of calcium nitrate on phenolic contents and antioxidant activities in aerial parts of borage. The split-plot experiment based on randomized complete block design with three replications in the research farm of Institute of Medicinal Plants, ACECR, located in Karaj was done from 2008 to 2009. Results showed that Phenolic content and antioxidant activity [IC50] in the various stages of growth significantly was different [p < 0.05]. Also, spraying of calcium nitrate had significant effect [p < 0.01] on antioxidant activity and phenolic content, but interaction effect of calcium nitrate and vegetative stages on amount of phenol and IC50 wasn't significant. Generally, results showed that spraying calcium nitrate throughout seed ripening increased antioxidant activity of borage plants. Considering to the borage plant is important in the formulation of health and food products, the increasing antioxidants compounds can be valuable