Is the yin-yang nature of Chinese herbal medicine equivalent to antioxidation-oxidation?

It has been suggested that yin-yang theory described in traditional Chinese medicine is somewhat equivalent to the modern theory of antioxidant-oxidant balance. Some yin-tonic Chinese herbal medicines possess antioxidant properties. In this context, the DNA protective effect of 12 yin-tonic and 13 yang-tonic herbs were tested using the single cell gel electrophoresis (comet) assay. Lymphocytes from three healthy subjects were pre-incubated with aqueous herb extract, and the comet assay was performed on treated, untreated, challenged and unchallenged cells in parallel, oxidant challenge being induced by 5 min exposure to hydrogen peroxide. Results using this ex vivo cellular assay showed protection by some herbs. Seven out of 12 yin-tonic Chinese herbs demonstrated decreased DNA damage after treatment while 10 out of 13 yang-tonic herbs showed protection. Among 25 herbs tested, rhizome of Ligusticum sinensis Oliv. and aerial part of Artemisia annua L. demonstrated greatest DNA protective effect. Results indicated that the yin nature of herbs may not be necessarily associated with superior antioxidative effect to yang-tonic herbs, at least in terms of DNA protection against oxidant challenge.