Quinocitrinines A and B, New Quinoline Alkaloids from Penicillium citrinum Thom 1910, a Permafrost Fungus

New citrinin derivatives isolated from Penicillium citrinum

“…Fractionation of this fungal extract resulted in the isolation of three new coupling compounds derived from citrinin (9) and 2,3,4-trimethyl-5,7-dihydroxy-2,3-dihydrobenzofuran (8) -penicitrinone A (1), penicitrinol A (2), and penicitrinone B (3) -and a new citrinin derivative -decarboxydihydrocitrinin (4) -along with 3-methoxy-1-methyl-4(1H)-quinolone (5) [1], quinolactacin A2 (6) [2,3], dihydrocitrinone (7) [4], 2,3,4-trimethyl-5,7-dihydroxy-2,3-dihydrobenzofuran (8) [5], citrinin (9) [5][6][7], quinocitrinin A or B (10) [8], and decarboxydihydrocitrinone (11) [6] (Fig. 1).…”

The Fungus Penicillium citrinum, Isolated from Permafrost Sediments, as a Producer of Ergot Alkaloids and New Quinoline Alkaloids Quinocitrinines

“…Using alkaloids of P. citrinum VKM FW-800 as an example, it can be postulated that secondary metabolites in this culture not only represent possible detoxification products but also play a key role (hitherto unknown) in primary metabolic processes. All metabolites produced by P. citrinum VKM FW-800 exhibit biological activity (including antimicrobial) [3,5]. Possibly, the ability to synthesize the set of the metabolites in question helped the fungus to survive during competition with other microorganisms several million years ago.…”

“…Plates were developed in system III, the zone corresponding to alkaloids was cut, and alkaloids were eluted with methanol. The eluate was filtered, and the content of alkaloids was determined by optical density at 314 nm using the molar extinction coefficient of quinocitrinine B [3]. The optical density of all solutions was measured in an SF-26 spectrophotometer (Russia).…”

“…It was discovered earlier that Penicillium citrinum strain VKM FW-800, isolated from Arctic permafrost sediments, synthesizes agroclavine I and epoxyagroclavine I-rare clavine ergot alkaloids with the 5 R ,10 S configuration of the ergoline nucleus [2]. Additionally, novel quinoline alkaloids quinocitrinines, quinocitrinine A and quinocitrinine B exhibiting biological activity (including antibiotic properties) were isolated from the culture liquid of this fungus [3].…”

“…To study the time course of culture growth and synthesis of alkaloids, samples were taken in triplicate at 24-h intervals. The growth of the fungus was assessed by changes in dry mycelium weight during culturing.Metabolites were extracted from culture-liquid filtrate and from vegetative mycelium as described earlier [2,3] and analyzed by TLC on silica gel plates (Silica gel 60 F 254 , Merck, Germany) in the following chloroform-methanol-25% NH 4 OH (conc.) systems differing in the proportion of components: (90 : 10 : 0.1; system I), (90 : 10 : 1; system II), and (80 : 20 : 0.2; system III).…”