Inducing new bioactive metabolites production from coculture of Pestalotiopsis sp. and Penicillium bialowiezense

Coculturing two or more fungi is a useful strategy to awaken the silent genes to produce structurally diverse and bioactive natural products. Through the coculture of Pestalotiopsis sp. and Penicillium bialowiezense, six new isoprenylated chromane derivatives, including two pairs of enantiomeric ones (1a/1b-2a/2b)and two optical pure ones (3-4), two new isoprenylated phenol glucoside derivatives (6-7), as well as eight known structural analogues (5 and 8-14), were obtained. The structures of these new compounds were characterized by NMR spectroscopy, single-crystal X-ray crystallography, and ECD calculation. The ? 10,11 double bond of pestaloficin D (5)was revised to E-configurated based on the extensive spectroscopic analyses. Compounds 1a/1b and 2a/2b were the first examples of enantiomeric isoprenylated chromane derivatives, which were successfully separated by chiral HPLC. Additionally, all the isolated compounds were evaluated for the in vitro ß-glucuronidase (GUS)and butyrylcholinesterase (BChE)inhibitory activities. Compounds 1a and 1b showed significant ß-glucuronidase inhibitory potency with IC 50 values of 7.6 and 10.3 µM, respectively. Compound 14 exhibited moderate BChE inhibitory activity with an IC 50 value of 21.3 µM. In addition, the structure-enzyme inhibitory activity relationship of compounds 1-14 is discussed.