Suaeda japonica is a halophytic plant that lives in mudflat at intertidal zone of western and southern coastal areas of Korea. The seawater-living plants showed a purple color during their whole life. In contrast, freshwater-living plants displayed a green color in leaves. When seawater-living plants were transferred to potting soil, the purple color was gradually changed to green in the leaves. The extracted purple pigment compound exhibited typical characteristics of betacyanin that were represented by water solubility, pH- and temperature-dependent color changes, sensitivity to light, UV-Vis spectra, and gel electrophoretic migration pattern. The LC-MS analysis of the extracted pigment compound showed the presence of two major protonated molecular ions ([M+H]+) at m/z 651.1 and m/z 827.1. Antioxidant activity of the pigment compound was determined using stable free radical DPPH assay. It was found to have an antioxidant activity that is linearly increased in proportion to the reaction time for up to 30 min, and the activity was comparable to that of control BHA at 9.0 ㎎/㎖. The anticancer activity against several tumor cell lines was also examined following the MTT assay. The significant growth inhibitory effect was observed on two tumor cell lines, SW-156 (human kidney carcinoma) and HEC-1B (human endometrial adenocarcinoma). Probably, the pigment compound may function as an osmolyte to uphold halotolerant physiological processes in saline environment.

Abstract
 Introduction
 Materials and Methods
  Plant collection and pigment extraction
  Analyses of pigment compound
  Antioxidant assay
  Assay for anticancer activity
 Results
  Plant morphology in different environmental conditions
  Extraction of pigment compound
  UV-Vis spectra
  Stability studies on pH, temperature, and light
  Gel electrophoretic migration pattern
  LC-MS pattern
  Antioxidant activity
  Anticancer activity
 Discussion
 References

• Sang Ho Chung(Department of Microbial and Nano Materials, Mokwon University) Corresponding author