New sesquiterpenes, JBIR-27 and -28, isolated from a tunicate-derived fungus, Penicillium sp. SS080624SCf1

Abstract

In the course of our screening program for novel metabolites from tunicate-derived fungi, novel sesquiterpenoids, named JBIR-27 (1) and -28 (2), together with known sporogen-AO1 and phomenone, were isolated from the culture broth of Penicillium sp. SS080624SCf1. The structures of 1 and 2 were determined to be eremophilane analogs on the basis of extensive NMR and MS analyses. Sporogen-AO1, phomenone and 2 showed cytotoxicity against human cervical carcinoma cell line HeLa at IC 50 values of 8.3, 19 and 92 mM, respectively, whereas 1 was inactive at a concentration of 80 mM. Keywords: cytotoxicity; JBIR-27; JBIR-28; Penicillium sp.; terpenoid; tunicate INTRODUCTION Many bioactive substances have been isolated from marine organisms, such as marine microorganisms, phytoplankton, algae, sponges and tunicates. Moreover, marine microorganisms have been studied as the important resources for new biologically active metabolites. 1 Especially, marine-derived fungi are emerging as an attractive source for discovering new bioactive compounds. 2 Indeed, cytotoxic metabolites, such as diketopiperazine alkaloids, 3 trichodermatides 4 and carbonarones, 5 have been isolated from metabolites of marine-derived fungi. Tunicates are a rich source of unique and biologically active metabolites. 1 However, there have been few reports of compounds isolated from tunicate-derived fungi. 6,7 Therefore, we attempted to isolate fungi from a tunicate, Didemnum molle, and obtain secondary metabolites from the fungal culture broths.In the course of chemical screening for novel compounds from the metabolites of tunicate-derived fungi, we isolated two novel sesquiterpenoid compounds, designated as JBIR-27 (1) and -28 (2), from the culture broth of Penicillium sp. SS080624SCf1 (Figure 1). In addition, we also isolated known derivatives, sporogen-AO1 8 and phomenone 9 (Figure 1). This paper describes the fermentation, isolation and brief biological activity of 1, 2, sporogen-AO1 and phomenone, in addition to the taxonomy of the producing microorganism. The structure elucidation of 1 and 2 is also reported.

Isolation of 2 new metabolites, JBIR-74 and JBIR-75, from the sponge-derived Aspergillus sp. fS14

“…Marine microorganisms, especially fungi, 4 are an untapped resource of novel bioactive substances such as diketopiperazine alkaloids, 5 trichodermatides 6 and carbonarones. 7 We have also reported the discovery of new sesquiterpenes, JBIR-27 and JBIR-28; 8 a new aspochracin derivative, JBIR-15; 9 new glycosyl benzenediols, JBIR-37 and JBIR-38; 10 and a new sorbicillinoid, JBIR-59 11 from marine-derived fungi. The Calcarea class of sponges has been recognized as a reliable source of richly bioactive metabolites possessing a 2-aminoimidazole skeleton.…”

Isolation of two new terpeptin analogs—JBIR-81 and JBIR-82—from a seaweed-derived fungus, Aspergillus sp. SpD081030G1f1

“…7 We also have reported new sesquiterpenes-JBIR-27 and JBIR-28-from a tunicate-derived fungus Penicillium sp. SS080624SCf1, 8 a new aspochracin derivative-JBIR-15-from a marine spongederived fungus Aspergillus sclerotiorum Huber Sp080903f04, 9 and new glycosyl benzenediols-JBIR-37 and JBIR-38-from a marine spongederived fungus, Acremonium sp. SpF080624G1f01.…”

JBIR-37 and -38, Novel Glycosyl Benzenediols, Isolated from the Sponge-Derived Fungus,Acremoniumsp. SpF080624G1f01

“…We have also reported the new sesquiterpenes, JBIR-27 and -28, from a tunicate-derived fungus, Penicillium sp. SS080624SCf1, 6) and the new aspochracin derivative, JBIR-15, from a marine spongederived fungus, Aspergillus sclerotiorum Huber Sp080903f04. 7) We therefore attempted to isolate fungi from the marine sponge, Demospongiae, to obtain novel substances from the fungal culture broths of marine origin.…”

“…SS080624SCf1, 6) and the new aspochracin derivative, JBIR-15, from a marine spongederived fungus, Aspergillus sclerotiorum Huber Sp080903f04. 7) We therefore attempted to isolate fungi from the marine sponge, Demospongiae, to obtain novel substances from the fungal culture broths of marine origin. We isolated two novel compounds designated as JBIR-37 (1) and -38 (2) from the culture broth of Acremonium sp.…”