Improvement of phytochemical and quality characteristics of <i>Dracocephalum kotschyi</i> by drying methods

This experiment was conducted to evaluate the effects of different drying methods on parameters and qualitative characteristics Dracocephalum kotschyi in a completely randomized design with three replications. Treatments included shade as control, sun drying, cabinet (CD at 50 60°C), refractance window (RWD), infrared (IRD) 200 300 W, combination RWD+ IRD W. According results, IRD, RWD, effectively maintained valuable secondary metabolites compared conventional methods. The maximum total phenol content (2.7 2.66 mg GAE/g dry weight), flavonoid (2.26 2.33 QE/g antioxidant activity (79% 78.33%), essential oil (0.65% 0.76%) were obtained from plants dried by RWD IRD. Samples had high color quality, acceptable green color, less browning. Also, reduced microbial contamination control other minimum aerobic mesophiles, mold, yeast, coliforms observed 3.11, 0, 1.47 log CFU/g W 3.17, 1, 1.30 RWD. D. CD 50°C contamination. Generally, according are suggested for similar herbs due shortening time, preserving improving quality properties plants.