Mucor plumbeus

Abstract Recent chemical studies on the marine soft corals and terrestrial plants have lesnlted in the isolation of several novel componnds. The soft corals, Pseudopterogorgia elisabethae and Cladiella species yielded several novel terpenoids, exhibiting antimicrobial activities. New steroids were isolated from terrestrial fungi, Mucor plumbeus and Coprims micaceus. Phytochemical studies on the Buxus hyrcana, collected from Iran, have yielded steroidal bases. This revdew describes the new natiual products exhibiting different bioactivities from the aforementioned sources. 

Buxus hyrcana, Cladiella, Coprinus micaceus, coral, marine, Mucor plumbeus, Pseudopterogorgia elisabethae, steroids, terpenoids, terrestrial... 

Bioactive Steroids from Mucor plumbeus and Coprnusmicaceus... 

Microbial natural product chemistiy has generated a number of bioactive natural products. For instance cyclosporine A FK506 and rapamycin are used as immunosuppressants [16]. Other examples of microbial metabolites, having potential biomedical application include antihyperlipidemics, lovastatin and guggulsterone [17, 18]. The crude extracts of Mucor plumbeus exhibited acetylcholinesterase (AChE) enzyme inhibition activity. Our detailed chromatographic work on this crude extract resulted in the isolation of mucoralactone A (11), a novel steroid containing a lactone moeity incorporated in its structure. 

Fig. 9. Biotransformation of dihydroquinidine (and acylated derivatives) to the corresponding (3S)-3-hydroxy compounds (as % observed at the reaction plateau), using various collection strains of Mucor plumbeus (ATCC American Type Culture Collection CBS Centraalbureau voor Schimmelcultures DSM Deutsche Sammlung von Mikroorganismen MMP Mycotheque of the Paris Museum of National History)...

Very recently, the chemoenzymatic preparation of nootkatone from valencene was described [150]. Nootkatone was prepared from valencene by copper(I) iodide catalysed oxidation with tert-butyl hydroperoxide and hydroxylated at C-9 by Mucor plumbeus and Cephalosporium aphidicola. 

Mucor plumbeus Rhizopus arrhizus various fungal strains... 

Fucose has been detected in many fungi. It is formed on hydrolysis of the cell walls of the yeast-like fungi Mucor adventitius, Mucor hiemalis, Mucor javanicus, Mucor plumbeus, Mucor racemosus, Mucor spinosus, and Mucor sylvaticus, and in Rhizopus oryzae, Rhizoptts tamari, Rhizopus tonkiniensis, and Zygorrhyncus vuillemmU. The acidic, exocellular polysaccharide of Mucor racemosus contains L-fucosyl residues. ... 

Sclareol, a natural product first isolated from the essential oil of Salvia sclarea L. (Labiatae) in 1931, is used for diverse applications in the perfumery and flavoring industries and in folk medicine. This diterpene has been described recently to be hydroxylated by three strains, i.e. Cunninghamella sp., Septomyxa affinis 66 and Mucor plumbeus 67, 68, leading essentially to hydroxylation reactions on the A ring of this compound (Fig. 16.1-12). Some of these metabolites could be used for further synthesis of some biologically active targets or as mammalian metabolism models. 

Recently, biotransformations have been performed by means of Mucor plumbeus [103]. The incubation of epicandicandiol (7) yielded foliol (16), sideritriol (40) and the tetrahydroxykaurane (G), while the incubation of candicandiol (6) gave canditriol (23) and the two polyhydroxy derivatives (H) and (I). The difference of activity due to the 7p-OH or 7a-OH configurations is discussed. 

Valerianol (35a), from Valeriana officinalis whose dried rhizome is traditionally used for its carminative and sedative properties, was biotransformed by Mucor plumbeus, to produce three metabolites, a bridged ether (35b), and a triol (35c), which might be formed via Cl-ClO epoxide, and 35d arises from double dehydration (Arantes et al., 1999). In this case, allylic oxidative compounds have not been found (Figure 20.16). 

FIGURE 20.91 Biotransformation of poiygodlol (295) by Mucor plumbeus, Rhizopus arrhizus, and Aspergillus niger. 

Squamulosone (77) was treated in the fungus Mucor plumbeus ATCC 4740 to give not only cyclopentanol derivatives (89, 90) but also C12 hydroxylated products (91-93) (Collins, Rnddock, et al., 2002) (Figure 15.31). 

The incubation of the same substrate (265) in Mucor plumbeus ATCC 4740 in high iron-rich medium gave 270, which was obtained from Curvularia lunata mentioned above, 268, 272, 273, 277, 278, and 279. In low iron medium, this fungus converted the same substrate 265 into three epoxides (274-276), a tetraol (280) with common metabolites (268,273,277,278), and 271, which was the same metabolite used by Curvularia lunata (Collins, Reynold, and Reese, 2002). It is interesting to note that only epoxides were obtained from the substrate (265) by Mucor fungus in low iron medium (Figure 15.83). 

FIGURE 15.83 Biotransformation of cadina-4,10(15)-dien-3-one (265) hy Mucor plumbeus. 

Albicanal (288) and (-)-drimenol (289) are simple drimane sesquiterpenoids isolated from the liverwort, Diplophyllum serrulatum, and many other liverworts and higher plants. The latter compound was incubated with Mucor plumbeus and Rhizopus arrhizus. The former microorganism converted 289 to 6,7a-epoxy- (290), 3p-hydroxy- (291), and 6a-drimenol (292) in the yields of 2%, 7%, and 50%, respectively. On the other hand, the latter species produced only 3P-hydroxy derivative (291) in 60% yield (Aranda et al., 1992) (Figure 15.90). 

Maalioxide (349), mp 65-66°, [a]n -34.4° obtained from the liverwort, Plagiochila sciophila was inoculated and cultivated rotatory (100 rpm) in Czapek-peptone medium (pH 7.0) at 30°C for 2 days. (-)-Maalioxide (349) (100 mg OO mL) was added to the medium and further cultivated for 2 days to afford three metabolites, ip-hydroxy-(350), ip,9P-dihydroxy- (351), and ip,12-dihydroxy-maalioxides (352), of which 351 was predominant (53.6%). When the same substrate was cultured with Aspergillus cellulosae in the same medium for 9 days, 7P-hydroxymaalioxide (353) was obtained as a sole product in 30% yield. The same substrate (349) was also incubated with the fungus Mucor plumbeus to obtain a new metabolite, 9P-hydroxymaalioxide (354), together with two known hydroxylated products (350,353) (Wang et al., 2006). 

The sclareolide (402) which is C12 oxo derivative of ambrox was incubated with Mucor plumbeus to afford three metabolites 3(3-hydroxy- (403,7.9%), ip-hydroxy- (404,2.5%), and 3-ketosclareolide (405, 7.9%) (Aranda etal., 1991) (Figure 15.115). 

---