Lichen substances

The lichen is an association between a fungus and a phytosynthetic symbiont, generally green algae or cyanobacteria. Lichens have a number of practical applications, especially as sources of medicinal substances. Usnea aciculifera Vain, a lichen growing widely and abundantly on the bark of Pinus dalatensis at Lam Dong Province, Vietnam, has not yet been chemically and pharmaceutically studied in Vietnam.

6p vidoctorstrange 06-05-2023 3 1   Download

Two xanthone compounds, praesorexanthone A (1) and praesorexanthone B (2), were isolated from the lichen Parmotrema praesorediosum (Nyl.) Hale (Parmeliaceae). Among them, praesorexanthone B is a new natural compound. Their chemical structures were unambiguously determined by the analysis of 1D and 2D NMR and high resolution ESI mass spectroscopic data, as well as by comparison of their NMR data with the ones in the literature.

5p nguaconbaynhay11 16-04-2021 8 2   Download

A phytochemical investigation was conducted on foliose lichen, Parmotrema tinctorum (Nyl.) Hale, collected in Lam Dong province, Vietnam. Color reactions for identification of lichen substances (+K deep yellow, +C red, +KC red, + P pale yellow) suggested the presence of atranorin, lecanoric acid, quinones, depsides, and xanthones containing two free hydroxyl groups in meta-position.

7p abcxyz123_02 03-03-2020 17 0   Download

Stirtonia ghattensis Sumesh N. Dudani, Nayaka, Komal K. Ingle & S. Joseph sp. nov. having UV+ white thallus, 4–6-spored asci, and 5(–7)-septate ascospores and lacking lichen substances is described as new to science.

8p caplock2711 21-02-2019 15 2   Download