No abstract

Seven undescribed scalarane sesterterpenoids, nambiscalaranes B–H (1–7), together with two known compounds, nambiscalarane (8) and aurisin A (9) were isolated from the cultured mycelium of the luminescent mushroom Neonothopanus nambi. Their structures were elucidated by thorough analysis of their 1D and 2D NMR spectroscopic data. The absolute configurations of 1–8 were determined by electronic circular dichroism (ECD) calculations and optical rotation measurements. The isolated sesterterpenoids were evaluated against A549, HT29, HeLa, and HCT-116 cancer cell lines, and against five bacterial strains. Compounds 3, 5, and 7 showed strong cytotoxicity against HCT-116 cell line, with IC50 values ranging from 13.41 to 16.53 µM, and showed no cytotoxicity towards Vero cells. Moreover, compound 8 inhibited the growth of Bacillus subtilis with a MIC value of 8 µg/mL, which was equivalent to the MIC value of the standard kanamycin.

Two new p-terphenyls, neonambiterphenyls A and B (1-2), a new benzoquinone, neonambiquinone A (3), together with six known sesquiterpenes (4-9), were isolated from the bioluminescent mushroom Neonothopanus nambi PW3. The isolated compounds were identified by mass, IR and spectroscopic analyses (1D and 2D NMR). Compounds 1-3 and 5-7 showed cytotoxicity against cancer cell lines, KB, NCI-H187 and MCF-7 with IC 50 values ranging from 1.45 to 49.31 µg/mL. In addition, compounds 1 and 5 showed cytotoxicity against Vero cells with IC 50 values of 38.72 and 32.90 µg/mL, respectively.

Aurisin A (1) and the culture medium of the luminescent mushroom Neonothopanus nambi showed antifungal activity against Phytophthora palmivora, which causes the root-rot disease of Monthong durian, in a preliminary greenhouse experiment. Moreover, a new natural product, neonambiquinone B (2), was isolated. Their structures were elucidated by mass, IR and extensive analysis of their 1D and 2D NMR spectroscopic data. The results demonstrated that the culture medium of N. nambi is a promising potential for their agricultural applications.