Perylenequinones from an endophytic Alternaria sp. of Pinus ponderosa

Abstract

The differential solvent extraction and further purification of fractions of endophytic Alternaria sp. isolated from Pinus ponderosa led to the isolation of further two perylenequinone compounds as 3,6,6a,9,10-pentahydroxy-7,8-epoxy-4-oxo-4,5,6,6a,6b,7,8,9-octahydroperylene (1) and 3,6,6a,7,10-pentahydroxy-4,9-dioxo-4,5,6,6a,6b,7,8,9-octahydroperylene (2). Structure of compounds 1–2 was determined on the basis of detailed spectroscopic analysis, as well as by comparison with literature reports. The antimicrobial, antileismanial, antimalarial and cytotoxic activities of compound 1 and 2 were evaluated.

Fungal perylenequinones

“…Compound ( 1 ) and ( 2 ) displayed antileishmanial activity against Leishmania donovani with IC 50 values of 2.55 and 4.40 μg/mL, respectively. Also compound ( 2 ) revealed antimalarial activity against both chloroquine sensitive (D6) (IC 50 4.24 μg/mL) and chloroquine resistant (W2) clones of Plasmodium falciparum (3.65 μg/mL), as well as cytotoxicity against mammalian kidney fibroblasts (VERO cells) with IC 50 value of 3.59 μg/mL (Tantry et al 2018 ). Altertoxins I–III ( 3 – 5 ) were described from Alternaria alternata .…”

“…Hudson and associates discovered a correlation between singlet oxygen ( 1 O 2 ) quantum yield and antiviral activity (Hudson et al 1997 ). Other remarkable biological properties of PQs have been noted, such as the prevention of skin diseases caused by fungal infections, antileishmanial, antimalarial, antimicrobial properties, and mutagenicity (Wang and Bao 1985 ; Stack and Prival 1986 ; Diwu 1995 ; Ma et al 2004 ; Fang et al 2006 ; Tantry et al 2018 ).…”

“…Fungi are the best source for PQs as 85% of all known PQs are reported from fungi, compared to 12% for Animalia , and only 3% for Plantae . PQ pigments are produced by a wide variety of molds, the most of which are phytopathogens, with few marine sponge-derived, endolichenic, and endophytic fungi (Weiss et al 1987 ; Pang et al 2018 ; Tantry et al 2018 ). Insects are an alternative source of PQs, such as rodoaphin, which is synthetized by aphids.…”

“…Several investigations have been conducted on the apoptotic and cytotoxic effects of some fungal PQs, including calphostin C ( 42 ), elsinochromes A ( 45 ), C ( 47 ), hypocrellin ( 49 ), and hypocrellin A ( 50 ). These studies highlighted their potential as promising anticancer medications and explored their application in cancer therapy (Dubauskas et al 1998 ; Fang et al 2006 ; Olivo and Ali-Seyed 2007 ; So et al 2018 ; Tantry et al 2018 ; Mastrangelopoulou et al 2019 ). Furthermore, Sharma et al ( 2013 ) have invented a patent (US 8,506,931 B2), that contains hypocrellin derivatives.…”

Naturally Occurring Partially Reduced Perylenequinones from Fungi

“…54 Compounds 23 (ATX XVIII) and 28 (ATX XXIII) showed activity against mammalian kidney fibroblasts (VERO cells) with IC 50 of 12.5 and 9.8 μM, respectively. 56,59 Interestingly, the perylenequinones that exhibited antitumor activity were those that possess the biphenyl skeleton.…”