New Record of Karoowia saxeti (Stizenb.) Hale in South Korea

Karoowia saxeti was recorded during the lichen field expedition in southern part of Korea in 2006. The lichen was found on the rock surface along coastal line. This species was easily recognized by chemistry (K+ yellow) and the presence of isidia. Thallus was saxicolous, subcrustose, more or less lobate at the center with clearly lobed margins, 2~6 cm broad and pale yellowish green. Thalli lobes were irregular, variable, up to 1.0mm wide, not branched, flat to more or less convex and contiguous to subimbricate. Upper surface of the thalli was continuous, emaculate, moderately isidiate. The isidia was subglobose to cynlindrical, darkening at the tips and unbranched. Low surface of the thalii was black with a spongy rhizoidal and lamellar layer. HPLC analysis proved the presence of stictic acid (K+ yellow), norstictic acid and usnic acid. This is the first record of the species in South Korea.

Antioxidative Activity of Lichen Thamnolia vermicularis in vitro

This study was aimed at evaluating the antioxidant activities of methanol extract of Thamnolia vermicularis. The antioxidant activity, reducing power, superoxide anion radical scavenging and free radical scavenging activities were studied. The antioxidant activity of the extract correlated with its concentration (0.2~2 mg/ml) in the reaction mixtures containing linoleic acid. Upto 67% of lipid peroxidation was inhibited by 2 mg/ml of the lichen extract. The extract showed strong free radical scavenging activity similar to that of BHA (positive control) in a manner of concentration dependent. The lichen extract also showed moderate effects on superoxide anoin scavenging activity and reducing power, which was not so effective as that of Quercetin and BHA used as positive controls. This study suggests that T. vermicularis lichen can be used as a novel source of natural antioxidant.