Prominent Anti-UV Activity and Possible Cosmetic Potential of Lignin-carbohydrate Complex

This review article summarizes the recent progress of ultraviolet rays (UV) protective substances, including our original reports. We have established a simple assay method for the determination of anti-UV activity that can be applicable to any kind of adherent cells. This method provides information of both anti-UV activity and cytotoxicity of any kind of samples even though those samples contain unknown amounts of test compounds. We found that lignin-carbohydrate complex (LCC) showed one- or two-order higher anti-UV activity compared to well-known lower molecular weight polyphenols and hot-water extracts of Kampo medicines and tea leaves. Among synthetic compounds, water-soluble azulenes showed the highest anti-UV activity. LCC showed additive or synergistic anti-UV activity with vitamin C. Alkaline extract of Sasa senanensis Rehder leaves (SE), an LCC-rich over-the-counter (OTC) drug, also showed potent antiviral and vitamin C-synergized radical scavenging activity. SE has been utilized to manufacture tooth paste, soap and gel cosmetic to increase the level of quality of life (QOL).