STUDIES IN THE BIOCHEMISTRY OF MICROORGANISMS ISOLATION AND ELUCIDATION OF STRUCTURE OF METABOLITES, FROM ASPERGILLUS STELLATUS –CURZI PENICILLIUM MARTENSII-BIOURGE

Abstract

From the mycelium of Aspergillus stellatus –Curzi besides mannitol, six new xanthones have been isolated. The proposed names, molecular formulae and the m.ps are tabled below:- i)Tajixanthoune;C25H26O6, m.p.157-158oC; [α] D25-80o ii)Shamixanthone;C25H26O5, m.p.153-154oC; [α] D25+6.6o iii)Ajamxanthone;C25H24O4, m.p.131-132oC; [α] D25+15.3o iv)Shahenxanthone;C25H28O7, m.p.163-164oC; [α] D25-19.2o v)Najamxanthone;C26H28O8, m.p.181-182oC; [α] D25-61.2o vi)Radixanthone;C26H30O9, m.p.201-202oC;-- Spectroscopic data and chemical evidence has shown Tajixanthone to be: 3,4,4a,14a-Tatrahydro-4, 8-dihydroxy-2,2,6,9,14a-pentamethyl-3-methylene-2H, 5H, 7H-pyrano [3,2:5,6] pyrano [3,2-b] xanthene 7-one*. Shamixanthone to have the structure : 1,2,3,3a,12, 12a-Hexhydro-1,9-dihydrioxy-11-(hydroxymethyl) -3,3,3a,38tetramethyl-2-methylene-10H-pentalene [2,1-b] xanthene-10-one. Ajamxanthone to be:-------------------------- 2,3,3a,12-Tetramethyl-2-hydroxy-11-(hydeoxymethyl)-3,3,3a-8-tetramethy-2-methylene -10H- pentaleno [2,1-b] xanthene-10 one** Similarly the structures of shahenxanthone and Najamxanthone have been established through chemical degradation and spectroscopic studies as 3,4-Dighyre-2,7-dihydroxy-3-(1-hydroxy-2-isopropylallyl)-5-(hydromxymethy1)-2,8-dimethl-2H, 6H-pyrano [3,2-b] xantheme-6-one and 3,4-dihydro-2, 7-dihydroxy-3-(1-hydroxy-2-isopropylallyl) -2,8-dimethyl -2H, 6H-pyrano [3,2-b] xanthene -6-one 5 acetate respectively. Penicilium martensii-Biourge when grown on a semi-synthetic medium produces a number of crystalline compounds viz: amudol, C7H8O3 C1, m.p. 146-147oC and an aromatic acid m.p. 175oC from broth, and amudane (also from broth),, C17H19O6C, m.p.195-196oC,--------------------------- orgostorol, C28H44O, m.p.168oC, m.p.163oC from mycelium. Amudane, amudene and anmjane are identified to be the known metabolites griseofulvin, dehydrogriseofulvin and dihygrogriseofulvin, and the aromatic acid as 6-methyl salicylic acid.