Natural Indigo

The main chemical constituents of Indigo Naturalis are indigo and indirubin, with trace constituents such as tryptanthrin and qingdainone.

The alcoholic extract of Indigo Naturalis (Baphicacanthus/Indigofera), at 0.5 g/mL, inhibits Bacillus anthracis, Klebsiella pneumoniae, Shigella dysenteriae, Vibrio cholerae, and both Staphylococcus aureus and Staphylococcus albus in vitro, but shows no inhibitory effect against typhoid bacilli, some staphylococci, or tubercle bacilli, possibly due to differences in extraction methods.

Contraindicated in cases of deficiency-cold or internal heat due to yin deficiency.