Experimental plants were also assayed for their total phenol contents. The amount of phenolics in the selected medicinal plant (A. calamus) extracts was determined with Folin–Ciocalteu reagent using the method of Bray and Thorpe (1954). Fresh leaf samples (100 mg) were extracted with 10 ml of 70% acetone. After centrifuging an aliquot of extracted solution, 1 ml of supernatant was added with 1 ml Folin–Ciocalteu reagent, and allowed to stand for few minutes. Then 2.0 ml of saturated sodium carbonate was added to the mixture. This solution was made up to 10 ml with deionized water. Absorbance of the resulting solution was determined at 650 nm, using a UV–vis spectrophotometer (Model, 119, Systronics India). Standard curve to estimate the concentration was prepared by using
catechol.