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The productions of cryptic metabolites including three undescribed drimane sesquiterpenoids, penicichrins A-C, and three known compounds from Penicillium chrysogenum were activated by the host Ziziphus jujuba medium. The structures were established by comprehensive analysis of spectroscopic data. The spiro β-lactone, and gem-dimethyl dihydroxylation in induced penicichrins A-C were rare in natural products. Cryptic metabolites, monaspurpurone was first found in Penicillium. 4-Methoxy-3-methylgoniothalamin, and 2-hydroxy-l-phenyl-l,4-pentanedione were second example of isolation. Penicichrin A, monaspurpurone, 4-methoxy-3-methylgoniothalamin, physcion, ergosterol, and ergosta-7,22-dien-3β-ol had antifungal activities against phytopathogens, P. chrysogenum, Alternaria alternata and Aspergillus fumigatus with MICs ≤2 μg/mL, and 2-hydroxy-l-phenyl-l,4-pentanedione had flowering activity. So the chemical constituents from Z. jujuba could induce the productions of cryptic metabolites with plant growth-promoting activity from endophyte P. chrysogenum.

Four undescribed ergostane-type steroids, (22E,24R)-4α,5α-epoxyergosta-9α,14β-dihydroxy-7,22-diene-3,6-dione, (22E,24R)-4α,5α-epoxyergosta-9α,14α-dihydroxy-7,22-diene-3,6-dione, 12α-hydroxyergosta-7,22,24(28)-triene-3-one, and 3β,12α-dihydroxyergosta-7,24(28)-diene, along with a known congener (22E,24R)-9α,14β-dihydroxyergosta-4,7,22-triene-3,6-dione, were isolated from the fungus Lasiodiplodia pseudotheobromae. Their structures were elucidated using NMR, HRESIMS, ECD calculation, and X-ray diffraction analyses. (22E,24R)-4α,5α-epoxyergosta-9α,14β-dihydroxy-7,22-diene-3,6-dione and (22E,24R)-4α,5α-epoxyergosta-9α,14α-dihydroxy-7,22-diene-3,6-dione are a pair of C-14 epimers possessing an unusual epoxy group between C-4 and C-5, which was demonstrated using single-crystal X-ray diffraction analyses. The absolute configurations of 12α-hydroxyergosta-7,22,24(28)-triene-3-one and 3β,12α-dihydroxyergosta-7,24(28)-diene were determined by ECD calculations. Moreover, 3β,12α-dihydroxyergosta-7,24(28)-diene exhibited neuroprotective activity in vitro in glutamate-treated SH-SY5Y cell lines.

The investigation of the metabolites from the endophytic fungus Xylaria sp. YM 311647 in solid fermentation resulted in the isolation of six undescribed compounds, namely xylarioxides A-F, respectively. These included one eremophilane sesquiterpene, three guaiane sesquiterpene glycosides, and two ergostane glycosides. The structures of the compounds were determined by extensive analyses of spectroscopic data, including 1D and 2D NMR, as well as HRESIMS data. The stereochemistry of xylarioxide A was confirmed by X-ray crystallographic analysis. All of the isolated compounds were assayed for their antifungal activities against seven phytopathogenic fungi and two human pathogenic fungi. Among them, xylarioxides A, E and F showed potent activities against the tested phytopathogens. Particularly, xylarioxide E exhibited the highest activity against Gibberella saubinetii, Curvularia lunata, and Colletotrichum gloeosporioides with MIC values of 4, 4, and 8 μg/mL, respectively, which were comparable to the positive control of nystatin. Interestingly, guaiane sesquiterpene glycosides have been rarely reported from fungal sources. Additionally, xylarioxide E represented an unusual naturally occurring 3,4-seco-steroidal glycoside with a seven-membered lactone in ring A.

Two undescribed triterpenes, tricholimbrins A and B, three undescribed steroids, tricholimbrins C‒E, one undescribed 4-chromanone derivative, along with 27 known compounds were isolated from fruiting bodies of the mushroom Tricholoma imbricatum. Tricholimbrins A and B are two polycyclic triterpenoids with a carbon degradation, while tricholimbrin C is a ring-rearranged steroid containing an aromatic moiety that might be derived from an ergosterol. Isocyathisterol, 3β,15α-dihydroxyl-(22E,24R)-ergosta-5,8(14),22-trien-7-one, demethylincisterol A3, and volemolide showed cytotoxicities to six human cancer cell lines. 3β-Hydroxyl-(22E,24R)-ergosta-5,8,22-trien-7,15-dione and 3β-hydroxyl-(22E,24R)-ergosta-5,8,22-trien-7-one showed preferable cytotoxicities against HL-60 while chaxine C and volemolide showed preferable cytotoxicities against A-549, with IC50 values less than 10 μM.

Seven previously undescribed polyketides, namely childinins A-G, and one previously undescribed 8,14-seco-ergosterol, namely childinasterone A, were obtained from the fruiting bodies of Daldinia childiae. Their structures and absolute configurations were established via extensive spectroscopic analyses, single-crystal X-ray diffraction, and TDDFT/ECD calculations. Childinins A represents the first example of natural product possessing a previously undescribed 6H-naphtho[2,1-c]chromen-6-one scaffold. The single crystal X-ray diffraction of childinasterone A unambiguously determined the absolute configuration of a 8,14-seco-ergosterol skeleton. Childinins A, B, F and G (MIC90 54.9 μg⋅mL-1) showed anti-bacterial activities. Childinasterone A showed significant anti-NO activity (IC50 21.2 μM) and weak activities against SMMC-7721, MCF-7 and SW480 cell lines.

Seven withanolides, including four previously unknown, were isolated from the acetone and ethanol extracts of cultivated specimens of Acnistus arborescens . These four compounds were identified as rel -(18 R ,22 R )-5 β ,6 β :18 β ,20-diepoxy-3 β ,18 α -dimethoxy-4 β -hydroxy-1-oxowith-24-enolide, rel -(20 R ,22 R )-5 β ,6 β -epoxy-4 β ,16 α ,20-trihydroxy-1-oxowitha-2,24dienolide, rel -(20 R ,22 R )-16 α -acetoxy-6 α -chloro-4 β ,5 β ,20-trihydroxy-1-oxowitha-2,24-dienolide and rel -(20 R ,22 R )-16 α -acetoxy-20-hydroxy-1-oxowitha-2,5,24-trienolide. Their structures were elucidated by interpretation of spectroscopic data (1D and 2D NMR), HRESIMS experiments and comparison with published data for similar compounds. Cytotoxicity of the isolated compounds was evaluated against a panel of four tumor cell lines (HL-60, HCT-116, SF-268 and PANC-1). Withanolide D was the most active, with an IC 50 value in the range of 0.3–1.7 μM, rel -(18 R ,22 R )-5 β ,6 β :18 β ,20-diepoxy-3 β ,18 α -dimethoxy-4 β -hydroxy-1-oxowith-24-enolide and rel -(20 R ,22 R )-5 β ,6 β -epoxy-4 β ,16 α ,20-trihydroxy-1-oxowitha-2,24dienolide were moderately active, while all the others were non-cytotoxic.

During a study on the chemistry and biological activity of Antrocaryon klaineanum Pierre, six new sterols including 4,24(28)-ergostadiene-6α,7α-diol (1), 6α-methoxy-4,24(28)-ergostadiene-7α,20S-diol (2), 6α-methoxy-4,24(28)-ergostadien-7α-ol (3), 20S-hydroxy-24(28)-ergosten-3-one (4), 7α-hydroxy-4,24(28)-ergostadien-3-one (5), and 24(28)-ergostene-3β,6α-diol (6) were characterized by physical and spectroscopic means. The known steroids 7 and 8 were also isolated. The crude extract and the isolated compounds were evaluated for their ability to inhibit the 3D7 strain of Plasmodium falciparum. Compounds 2, 3, and 8 showed potent activity while that of the crude extract was moderate.

Five previously undescribed metabolites, including acetylquestinol, two prenylated indole 3-carbaldehyde derivatives, an anthranilic acid derivative and an isochromone derivative, were isolated, in addition to eleven known compounds: palmitic acid, ergosterol 5,8-endoperoxide, emodin, physcion, questin, questinol, (11S, 14R)-cyclo(tryptophylvalyl), preechinulin, neoechinulin E, echinulin and eurocristatine, from the culture of the endophytic fungus Eurotium chevalieri KUFA 0006. The structures of the previously undescribed compounds were established based on an extensive 1D and 2D NMR spectral analysis as well as HRMS and IR data. In case of 2-(2, 2-dimethylcyclopropyl)-1H-indole-3-carbaldehyde and 6, 8-dihydroxy-3-(2S-hydroxypropyl)-7-methylisochromone, the absolute configurations of their stereogenic carbons were established based on comparison of their experimental and calculated ECD spectra. All the compounds, except for palmitic acid and ergosterol 5, 8-endoperoxide, were evaluated for their antibacterial and antibiofilm activities against two Gram-positive and two Gram-negative bacteria, as well as multidrug-resistant isolates from the environment. Emodin not only exhibited moderate antibacterial activity against the Gram-positive bacteria but also showed strong synergistic association with oxacillin against MRSA Staphylococcus aureus. © 2017 Elsevier This work was partially supported by national funds provided by FCT- Foundation for Science and Technology and European Regional Development Fund (ERDF) and COMPETE, under the projects PEst-C/MAR/LA0015/2013, PTDC/MAR-BIO/4694/2014 as well as by the project INNOVMAR - Innovation and Sustainability in the Management and Exploitation of Marine Resources (reference NORTE-01-0145-FEDER-000035, within Research Line NOVELMAR/INSEAFOOD/ECOSERVICES), supported by North Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF)?. W. W. May Zin thanks the Lotus Unlimited Project under the ERASMUS MUNDUS ACTION 2-EU-Asia Mobility Project for a PhD's scholarship. We thank Mrs. J?lia Bessa and Ms. Sara Cravo for technical support.

Ganoderic acids (GAs) in Ganoderma lingzhi exhibit anticancer and antimetastatic activities. GA yields can be potentially improved by manipulating G. lingzhi through genetic engineering. In this study, a putative lanosterol synthase (LS) gene was cloned and overexpressed in G. lingzhi. Results showed that its overexpression (OE) increased the ganoderic acid (GA) content and the accumulation of lanosterol and ergosterol in a submerged G. lingzhi culture. The maximum contents of GA-O, GA-Mk, GA-T, GA-S, GA-Mf, and GA-Me in transgenic strains were 46.6 ± 4.8, 24.3 ± 3.5, 69.8 ± 8.2, 28.9 ± 1.4, 15.4 ± 1.2, and 26.7 ± 3.1 μg/100 mg dry weight, respectively, these values being 6.1-, 2.2-, 3.2-, 4.8-, 2.0-, and 1.9-times higher than those in wild-type strains. In addition, accumulated amounts of lanosterol and ergosterol in transgenic strains were 2.3 and 1.4-fold higher than those in the control strains, respectively. The transcription level of LS was also increased by more than five times in the presence of the G. lingzhi glyceraldehyde-3-phosphate dehydrogenase gene promoter, whereas transcription levels of 3-hydroxy-3-methylglutaryl coenzyme A enzyme and squalene synthase did not change significantly in transgenic strains. This study demonstrated that OE of the homologous LS gene can enhance lanosterol accumulation. A large precursor supply promotes GA biosynthesis.

The Zygomycetes fungus Mortierella alpina was cultured to growth arrest to assess the phytosterol biosynthesis pathway in a less-advanced fungus. The mycelium was found to produce 13 sterols, but no ergosterol. The sterol fractions were purified to homogeneity by HPLC and their identifies determined by a combination of GC-MS and 1H NMR spectroscopy. The principal sterol of the mycelium was cholesta-5, 24-dienol (desmosterol) (83%), with lesser amounts of 24beta-methyl-cholesta-5,25(27)-dienol (codisterol) (2%), 24-methyldesmosterol (6%), 24(28)-methylene cholesterol (3%) and lanosterol (3%) and several other minor compounds (3%). The total sterol accounted for approximately 0.07% of the mycelial dry wt. Mycelium fed methionine-methyl-2H3 for 6 days, generated 3 2H-24-methyl(ene) sterols, [C28-2H2]24(28)-methylenecholesterol, [C28-2H3]24-methylcholesta-5,24-dienol and [C28-2H3]24beta-methyl-cholesta-5,25(27)-dienol. The formation of the 24-methyl sterols seems to be catalyzed by the direct methylation of a common Delta24-acceptor sterol thereby bypassing the intermediacy of an isomerization step for rearrangement of the Delta24(28)-bond to Delta25(25)-position as operates in Ascomycetes fungi and all plants.

The cell lipids of the zygomycete Absidia corymbifera F-965 extracted with isopropanol and CHCl3-MeOH mixtures at the exponential growth phase comprise 20+/-2% of mycelium dry wt. The lipids consist of: triacylglycerols (51% of the total lipids extracted), diacylglycerols (9%), monoacylglycerols (3%), ergosterol (5%), ergosterol peroxide (5alpha,8alpha-epidioxyergosta-6,22-diene-3beta-ol) (3%), fatty-acid esters of ergosterol (less than 0.5%), free fatty acids (4%), glucocerebroside (3%), and glycerophospholipids (22%). The main phospholipids are phosphatidylethanolamine (39% of the total phospholipids), phosphatidyl-myo-inositol (17%), diphosphatidylglycerol (12%), phosphatidic acid (7%), phosphatidylcholine (6%), phosphatidylglycerol (3%), and two unusual phospholipids reported earlier, N-acetylphosphatidylethanolamine (7%) and N-ethoxycarbonyl phosphatidylethanolamine (9%). In addition, two unknown acidic phospholipids are present in traces. Saturated fatty acids of the lipids are dominated by n-hexadecanoic acid and unsaturated ones by octadecenoic acid; octadecadienoic and octadecatrienoic acids are present in lesser amounts. Ergosterol peroxide as well as the above glucocerebroside which contains 9-methylsphinga-4(E),9(E)-dienine have first been revealed in zygomycetes.

Erinarols G-J and 10 known ergostane-type sterols were isolated from a methanol extract of the dried fruiting bodies of Hericium erinaceum. Their chemical structures were elucidated using extensive spectroscopic analyses including 1D and 2D NMR experiments and HR-ESI-MS analysis, as well as through comparison with previously reported data. Anti-inflammatory effects of the isolated compounds were evaluated in terms of inhibition of tumor necrosis factor α (TNF-α) and nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated murine RAW264.7 macrophage cells. The results showed that erinarols H and J, as well as 2 of the ergostane-type sterols exhibited inhibitory activity against TNF-α secretion, with inhibition values ranging from 33.7% to 43.3% at 10 μM. Erinarols J and three ergostane-type sterols exhibited significant inhibitory effects against NO production, with inhibition values ranging from 38.4% to 71.5% at 10 μM.

Sterol C24-methyltransferases (SMTs) constitute a group of sequence-related proteins that catalyze the pattern of sterol diversity across eukaryotic kingdoms. The only gene for sterol alkylation in green algae was identified and the corresponding catalyst from Chlamydomonas reinhardtii (Cr) was characterized kinetically and for product distributions. The properties of CrSMT were similar to those predicted for an ancient SMT expected to possess broad C3-anchoring requirements for substrate binding and formation of 24β-methyl/ethyl Δ(25(27))-olefin products typical of primitive organisms. Unnatural Δ(24(25))-sterol substrates, missing a C4β-angular methyl group involved with binding orientation, convert to product ratios in favor of Δ(24(28))-products. Remodeling the active site to alter the electronics of Try110 (to Leu) results in delayed timing of the hydride migration from methyl attack of the Δ(24)-bond, that thereby produces metabolic switching of product ratios in favor of Δ(25(27))-olefins or impairs the second C1-transfer activity. Incubation of [27-(13)C]lanosterol or [methyl-(2)H3]SAM as co-substrates established the CrSMT catalyzes a sterol methylation pathway by the "algal" Δ(25(27))-olefin route, where methylation proceeds by a conserved SN2 reaction and de-protonation proceeds from the pro-Z methyl group on lanosterol corresponding to C27. This previously unrecognized catalytic competence for an enzyme of sterol biosynthesis, together with phylogenomic analyses, suggest that mutational divergence of a promiscuous SMT produced substrate- and phyla-specific SMT1 (catalyzes first biomethylation) and SMT2 (catalyzes second biomethylation) isoforms in red and green algae, respectively, and in the case of SMT2 selection afforded modification in reaction channeling necessary for the switch in ergosterol (24β-methyl) biosynthesis to stigmasterol (24α-ethyl) biosynthesis during the course of land plant evolution.

Activity guided fractionations led to the isolation of two antitumor compounds 5 alpha,8 alpha-epidioxy-24(R)-methylcholesta-6,22-dien-3 beta-D-glucopyranoside and 5,6-epoxy-24(R)-methylcholesta-7,22-dien-3 beta-ol from the methanol extract of Cordyceps sinensis. Two previously known compounds, ergosteryl-3-O-beta-D-glucopyranoside and 22-dihydroergosteryl-3-O-beta-D-glucopyranoside were also isolated. The structures of hitherto unknown sterols were established by 1D and 2D NMR spectroscopic techniques with the former synthesized in order to confirm the identity of the sugar moiety by chemical correlation. The glycosylated form of ergosterol peroxide was found to be a greater inhibitor to the proliferation of K562, Jurkat, WM-1341, HL-60 and RPMI-8226 tumor cell lines by 10 to 40% at 10 micrograms/ml than its previously identified aglycone, 5 alpha,8 alpha-epidioxy-24(R)-methylcholesta-6,22-dien-3 beta-ol.

The sterol composition of spores from 16 species of arbuscular mycorrhizal fungi belonging to the order Glomales were examined by GC–MS. The major compound was found to be 24-ethylcholesterol (up to 85%) followed by cholesterol (up to 15%). Several other sterols such as 24-methylcholesterol, Δ5-avenasterol and 24-ethylcholesta-5,22-dien-3 β -ol were also detected. Significant amounts of α -amyrin, a common vascular plant triterpene, were present in the spores of all the fungal species analyzed. The absence of ergosterol, a classical fungal sterol, is discussed in relation to fungal evolution.

Spirostanol saponin permeabilization of Candida albicans cells resulted in phosphate (Pi) leakage from these cells. Pre-incubation of C. albicans suspension cultures with ergosterol or cycloiridals inhibited Pi leakage when cells were subjected to saponins. Saponins were shown to precipitate ergosterol but not cycloiridals. Inhibition of Pi leakage in the presence of cycloiridals could thus be due to their incorporation into cell membranes. Cycloiridals, which were previously shown to modify fluidity parameters in artificial phospholipid bilayers, seem in vivo to have a protective effect on membranes against surfactant (saponin) injury.

The sterol composition of Venturia inaequalis strains sensitive and resistant to sterol demethylation-inhibiting fungicides (DMI) were analysed. Without DMI treatment, both strains contained ergosta-5,7-dien-3β-ol, ergosterol, ergosta-7,24(241)-dien-3β-ol and ergost-7-en-3β-ol. Ergosta-5,7-dien-3β-ol was the main sterol in both strains. Treatment with fenarimol decreased the 4-desmethyl sterols and accumulated eburicol in both strains, indicating that this fungicide inhibits C14-demethylase of not only the sensitive strain but also the resistant strain. The accumulation of eburicol in the resistant strain occurred at higher concentration of fenarimol than in the sensitive strain.

From the neutral fraction of the acetone extract of mature wheat straw ( Triticum aestivum ) two new steroid ketones: (24 R )-14α-methyl-5α-ergostan-3-one and 14α-methyl-5α-cholestan-3-one and two new tetracyclic triterpenoids: cycloart-5-ene-3β,25-diol and cycloart-3β,25-diol together with the known compounds: cholesterol, ergosterol, campesterol, stigmasterol, sitosterol, spinasterol and stigmastanol were identified.

The effects of the solasodine-based glycoalkaloids, solasonine and solamargine, on the permeability of phosphatidylcholine liposomes containing different free sterols have been investigated. Solamargine was consistently the more active compound and caused major lysis of cholesterol-, stigmasterol- and ergosterol-containing liposomes, while solasonine was without effect on cholesterol liposomes and only slightly disruptive to stigmasterol and ergosterol liposomes. Liposomes lacking sterols were not lysed by either compound. In vitro , solamargine also bound effectively with all three sterols, but solasonine did so only with cholesterol and to a lesser degree than solamargine. Both glycoalkaloids, but especially solamargine, caused greater leakage from cholesterol liposomes when the sterol level was increased. Neither compound disrupted cholesterol liposomes at sub-neutral pH, but solamargine became highly active at pH 7 and above, while solasonine remained inactive. Findings are compared with similar properties of the structurally related, but solanidine-based, glycoalkaloids of potato, solanine and chaconine.

Two 24β-alkyl-Δ 5,7 -sterols, ergosterol (51% of the sterol mixture) and 7-dehydroporiferasterol (30%), were the principal sterols of Chlorella vulgaris . In addition two 24β-methyl-Δ 9(11) -sterols, 24β-methyl-5α-cholest-9(11)-en-3β-ol and 14α,24β-dimethyl-5α-cholest-9(11)-en-3β-ol, and two 24β-alkyl-Δ 5,7,9(11) -sterols, 9(11)-dehydroergosterol and 24β-ethylcholesta-5,7,9(11),22 E -tetraen-3β-ol, were isolated and identified from among the other Δ 5 - and Δ 7 -sterols. This is the first report of the natural occurrence of 24β-methyl-5α-cholest-9(11)-en-3β-ol as well as the first report of the detection of 24β-ethylcholesta-5,7,9(11),22 E -tetraen-3β-ol in an alga.

In the mycelium of all the Fusarium species studied, the major sterol was ergosterol in the absence of fenpropimorph. In the presence of this fungicide fenpropimorph-sensitive strains, with the exception of F. nivale , accumulated mainly Δ 8,14 -sterols and tolerant ones accumulated either both Δ 8,14 - and Δ 8 -sterols or only Δ 8 -sterols. This seemed to indicate that fenpropimorph toxicity was related to sterol Δ 14 -reductase sensitivity. In F. nivale , which was highly sensitive to fenpropimorph, the accumulation of only Δ 8 -sterols indicated that the main target enzyme was sterol Δ 8 →Δ 7 -isomerase. In addition to Δ 8,14 -and Δ 8 -sterols, squalene was accumulated in very high amounts in several strains; the level of squalene accumulation did not seem to be correlated with fenpropimorph sensitivity.

A new polyoxygenated ergosterol derivative, as well as three known steroids and a calvatic acid derivative were isolated fromLasiosphaera nipponica. The structures of these compounds were established by chemical and spectroscopic means.

A new glycoside of ergosta-7,22-diene-3,5,6-triol was isolated from the dry fruiting body of Hericum erinacens and the structure was established by chemical and spectroscopic means. Six ergosterol derivatives were also isolated from H. erinacens .

Treatment of Botrytis cinerea with a novel fungicide SSF-109, (dl)-cis-1-(4-chlorophenyl)-2-(1H-1,2,4-triazol-1-yl)cyclo-heptanol (0.45μgml−1), gave five 14α-methyl sterols, 24-methylene-24(25)-dihydrolanosterol, 24-methylene-24(25)-dihydrolanosten-3-one, obtusifoliol, obtusifolione, and 14α-methylfecosterol, together with ergosterol and ergosta-5,8,22-trien-3β-ol. SSF-109 was found to inhibit the biosynthesis of ergosterol at the 14α-demethylation step.

From extracts of the dried oyster fungus, Pleurotus ostreatus , three steroidal fractions were obtained. The major fraction was proved to be ergosterol and the second a mixture of two fatty acid esters of ergosterol, which could not be fully resolved. The minor fraction contained ergosta-4,6,8,22-tetraen-3-one, which has not been recorded previously. © 1997 Elsevier Science Ltd. All rights reserved

The role of ginseng saponins (ginsenosides) as modulators or inhibitors of disease is vague, but our earlier work supports the existence of an allelopathic relationship between ginsenosides and soilborne microbes. Interestingly, this allelopathy appears to significantly promote the growth of the important ginseng pathogen, Pythium irregulare while inhibiting that of an antagonistic non-pathogenic fungus, Trichoderma hamatum. Herein we report on the apparent selective metabolism of 20(S)-protopanaxadiol ginsenosides by an extracellular glycosidase from P. irregulare. Thus, when P. irregulare was cultured in the presence of a purified (> 90%) ginsenoside mixture, nearly all of the 20(S)-protopanaxadiol ginsenosides (Rb1, Rb2, Rc, Rd, and to a limited extent G-XVII) were metabolized into the minor ginsenoside F2, at least half of which appears to be internalized by the organism. No metabolism of the 20(S)-protopanaxatriol ginsenosides (Rg1 and Re) was evident. By contrast, none of the ginsenosides added to the culture medium of the non-pathogenic fungus T. hamatum were metabolized. The metabolism of 20(S)-protopanaxadiol ginsenosides by P. irregulare appears to occur through the hydrolysis of terminal monosaccharide units from disaccharides present at C-3 and/or C-20 of ginsenosides Rb1, Rc, Rb2, Rd and G-XVII to yield one major product, ginsenoside F2 and one minor product (possibly G-III). A similar transformation of ginsenosides was observed using a crude protein preparation isolated from the spent medium of P. irregulare cultures.

Ginseng saponins (ginsenosides) were isolated from soil associated with the roots of commercially grown American ginseng (Panax quinquefolius L.), identified via LC-MS and quantified via analytical HPLC. The ginsenosides, including F(11), Rb(1), Rb(2), Rc, Rd, Re and Rg(1), represented between 0.02 and 0.098% (average 0.06%) of the mass of the soil collected from roots annually between 1999 and 2002. The same ginsenosides were also isolated from run-off of undisturbed plants grown in pots in a greenhouse using a root exudate trapping system. To investigate (1) whether these saponins could influence the growth of pythiaceous fungi pathogenic to ginseng, and (2) whether soil levels of ginsenosides were sufficient to account for any effects, bioassays were completed using a crude saponin extract and an ecologically relevant concentration of purified ginsenosides. Thus, when cultured on media containing crude saponins, the colony weight of both Phytophthora cactorum and Pythium irregulare was significantly greater than that of control, indicating a strong growth stimulation by ginsenosides. The growth of Pythium irregulare was also significantly stimulated after addition of an ecologically relevant, low concentration (i.e. 0.06%) of purified ginsenosides to culture medium. By contrast, growth of the saprotrophic fungus Trichoderma hamatum was slightly (but not significantly) inhibited under the same conditions. These results imply that ginsenosides can act as allelopathic stimulators of the growth of pythiaceous fungi in the rhizosphere, and this may contribute to the disease(s) of this crop.

Two withanolides, 20beta-hydroxy-1-oxo-(22R)-witha-2,5,24-trienolide (1) and withacoagulin (2), along with a known withanolide, 17beta-hydroxy-14alpha, 20alpha-epoxy-1-oxo-(22R)-witha-3,5,24-trienolide (3) were isolated from Withania coagulans. Their structures were elucidated with the help of different spectroscopic techniques.

Cyathisterone (ergosta-7,22-diene-3,6-dione) and cyathisterol (8β-hydroxyergosta-4,6,22-trien-3-one), two new steroids, have been isolated from Calvatia cyathiformis along with two known ergosterol derivatives, ergosta-4,7,22-triene-3,6-dione and ergosta-4,6,8(14),22-tetraen-3-one. Their molecular structures were defined by spectroscopic means and chemical correlations.

Analysis of sterols in mycelia of the ascomycete, Leptosphaeria maculans by gas chromatography-mass spectrometry revealed that ergosterol comprised 95% of the total sterols, with eight other sterols comprising the remaining 5%. Six of these latter sterols were putative precursors of ergosterol and their presence suggested a pathway for ergosterol biosynthesis in this fungus. Ergosterol biosynthesis in fungi is inhibited by the triazole antifungal agent flutriafol. When L. maculans was grown in the presence of flutriafol, ergosterol content decreased while two 14 alpha-methylated sterols, 24-methylene dihydrolanosterol and obtusifoliol, accumulated.

Four new des-A-ergostane derivatives including blazeispirols B, C, E and F were isolated from the cultured mycelia of fungus Agaricus blazei Murill and were established to be (20S, 22R, 23R, 24S)-14beta,22: 22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9,11-tetraen-23-ol; (20S, 22S, 23R, 24S)-14beta,22: 22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9-trien-23-ol; (20S, 22S, 23R, 24S)-14beta, 22: 22, 25-diepoxy-5-methoxy-des-A-ergosta-5,7,9,11-tetraene-19,23-diol and (20S, 22S, 23R, 24S)-14beta,22: 22,25-diepoxy-des-A-ergosta-5,7,9-triene-5,23-diol by comparison of extensive 1D and 2D NMR spectral data with that of blazeispirol A.

Six withanolide-type steroids, named as cilistols a, b, d, q, g and f, respectively, were isolated from the leaves of Solanum cilistum . The major component among them, cilistol a, was characterized as (22 R , 24 S , 25 R , 26 R )-1-oxo-22, 26; 24, 25-diepoxy-17α, 26-dihydroxyergost-2,5-diene on the basis of spectroscopic properties and X-ray crystallographic analysis; the other isolated compounds had closely related structures. This is the first report of withanolide-type steroids in the Solanum genera.

Demethylmacrosporin (1,3,7-trihydroxy-6-methylanthraquinone) has been isolated from Dichotomophthora lutea ( Dactylaria lutea ), strain NHL 2996, isolated from the atmosphere in Japan, together with macrosporin, tetrahydroanthraquinones, altersolanols A and B, and ergosterol. It is a very rare example of the isolation of a 7-hydroxyanthraquinone from a fungus.

Botrytis cinerea and Pyrenophora teres , grown in liquid culture, contained only C 28 -sterols, principally ergosterol and ergosta-5,8,22-trienol.

Two amphotericin B resistant mutants of Ustilago maydis were isolated following direct selection from a wild-type population. Each mutant was demonstrated to be cross-resistant to nystatin yet remained sensitive to azoles. Sterol analysis indicated a sterol profile similar to the parent strain, precluding the involvement of an alteration in ergosterol biosynthesis as the cause of polyene resistance.

Six new ergostane glycosides, designated as petunioside A, petunioside B, 24-epipetunioside B, petunioside C, 24-epipetunioside C and petunioside D, were isolated from the methanolic extract of the fresh aerial parts of Petunia hybrida. Their structures were determined by means of spectroscopic analysis and single crystal X-ray analysis.

Four new withanolide glycosides, (20R,22R)-O-(3)-[beta-D- xylopyranosyl(1----3), beta-D-xylopyranosyl(1----4)]-beta-D-glucopyranosyl-3 beta,20-dihydroxy-1 alpha-acetoxy-witha-5,24-dienolide, (20R,22R)-O-(3)-[beta-D-xylopyranosyl(1----3), beta-D-glucopyranosyl(1----4)]-beta-D-glucopyranosyl-3 beta,20-dihydroxy-1 alpha-acetoxy-witha-5,24-dienolide, (20R,22R)-O-(3)-[beta-D- glucopyranosyl(1----3), beta-D-glucopyranosyl(1----4)]-beta-D-glucopyranosyl- 3 beta,20-dihydroxy-1 alpha-acetoxy-witha-5,24-dienolide and (20R,22R)-O-(3)-[beta-D-glucopyranosyl(1----3), beta-D- glucopyranosyl(1----4)]-beta-D-glucopyranosyl-3 beta, 12 beta,20-trihydroxy- 1 alpha,acetoxy-witha-5,24-dienolide, named dunawithanines C, D, E and F, respectively, were isolated from Dunalia australis. Their structures were elucidated on the basis of spectral and chemical evidence, especially NMR data of the peracetates.

The effects of 2-(4-chlorophenyl)-triethylamine (CPTA) upon carotenogenesis in Rhodotorula glutinis , and upon various lipoidal constituents of R. rubra were studied. CPTA was found to cause the accumulation of lycopene and γ-carotene and to inhibit the formation of fatty acids and ergosterol. Upon removal of the inhibitor lycopene was metabolized to the cyclic carotenes and the levels of ergosterol increased. It was proposed that CPTA inhibits the cyclase enzyme of carotenogenesis, inhibits the formation of ergosterol, and causes the build-up of intermediates of these compounds.

A study was made of the sterol glucosylating ability of cell-free homogenates obtained from 16 species of photosynthesizing and nonphotosynthesizing lower plants (2 species of Chlorophyceae, 2 species of Cyanophyceae, 1 species of Phycomycetes, 3 species of Ascomycetes, 3 species of Basidomycetes, 1 species of Myxomycetes, 3 species of Musci and 1 species of Sphenopsida). Except for the blue-green and green algae, all the remaining species showed distinct in vitro synthesis of steryl monoglucosides from UDPG and cholesterol or sitosterol. Preliminary studies on the specificity of the relevant enzymes pointed to a correlation between the sterol composition of the plant and the specificity of its glucosylating enzyme. The enzyme from Ascomycetes and Basidomycetes utilized ergosterol better than cholesterol or sitosterol. Enzymic preparations from mosses utilized sitosterol the best.

When Chlorella sorokiniana was grown in the presence of 4 ppm AY-9944 total sterol production was unaltered in comparison to control cultures. However, inhibition of sterol biosynthesis was shown by the accumulation of a number of sterols which were considered to be intermediates in sterol biosynthesis. The sterols which were found in treated cultures were identified as cyclolaudenol, 4α,14α-dimethyl-9β,19-cyclo-5α-ergost-25-en-3β-ol, 4α,14α-dimethyl -5α-ergosta-8,25-dien-3β-ol, 14α-methyl-9β,19-cyclo-5α-ergost-25-en-3β-ol, 24-methylpollinastanol, 14α-methyl-5α-ergost-8-en-3β-ol, 5α-ergost -8(14)-enol, 5α-ergost-8-enol, 5α-ergosta-8(14),22-dienol, 5α-ergosta-8,22-dienol, 5α-ergosta-8,14-dienol, and 5α-ergosta-7,22-dienol, in addition to the normally occurring sterols which are ergosterol, 5α-ergost-7-enol, and ergosta-5,7-dienol. The occurrence of these sterols in the treated culture indicates that AY-9944 is an effective inhibitor of the Δ 8 → Δ 7 isomerase and Δ 14 -reductase, and also inhibits introduction of the Δ 22 -double bond. The occurrence of 14α-dimethyl-5α-ergosta-8,25-dien-3β-ol and 14α-methyl-9β,19-cyclo-5α-ergost -25-en-3β-ol is reported for the first time in living organisms. The presence of 25-methylene sterols suggests that they, and not 24-methylene derivatives, are intermediates in the biosynthesis of sterols in C. sorokiniana .