Evaluation of three antioxidants to reduce browning in Hemarthria compressa callus

Browning and subsequent cell death in Hemarthria compressa callus is a serious problem reducing the effectiveness of this culturing system. This study evaluated three antioxidants (activated carbon, polyvinyl pyrrolidone, and vitamin C) for their potential to reduce browning. These agents were added into subculture media and incubated under different subculture cycles (10, 15, 20, 30 d) and temperatures (21, 23, 25, 27 ℃). Results showed that adding activated carbon (2.0 g·L-1), and incubating at （23±2）℃ for 10 d reduced the browning rate significantly and did not decrease callus growth. This culturing technique will allow more routine use of H.compressa callus in tissue culture and gene transformation experiments.