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1.  (6S*)-6-[(1S*,2R*)-1,2-Di­hydroxy­pent­yl]-4-meth­oxy-5,6-di­hydro-2H-pyran-2-one 
The title compound, C11H18O5, was isolated from a liquid culture of Pestalotiopsis sp. In the mol­ecule, the pyran-2-one ring assumes a half-chair conformation. The two terminal C atoms of the pentyl group were refined as disordered over two sets of sites, with refined occupancies of 0.881 (10) and 0.119 (10). In the crystal, mol­ecules are linked via O—H⋯O hydrogen bonds forming a three-dimensional network.
PMCID: PMC3884319  PMID: 24454095
2.  Endophytic Fungal Flora from Roots and Fruits of an Indian Neem Plant Azadirachta indica A. Juss., and Impact of Culture Media on their Isolation 
Indian Journal of Microbiology  2011;51(4):469-476.
Azadirachta indica A. Juss. (neem), native to India, is well known worldwide for its insecticidal and ethanopharmacological properties. Although endophytic microbes are known from this plant as only leaves and stems were the subjects of past reports. Now, a variety of procedures and a number of different media were used to isolate the maximum number of endophytic fungi from unripe fruits and roots. A total of 272 isolates of 29 filamentous fungal taxa were isolated at rate of 68.0% from 400 samples of three different individual trees (at locations-Az1, Az2, Az3). Mycological agar (MCA) medium yielded the highest number of isolates (95, with a 14.50% isolation rate) with the greatest species richness. Mycelia Sterilia (1, 2, 3) accounted for 11.06%, Coelomycetes 7.25%, while Hyphomycetes showed the maximum number of representative isolates (81.69%). Mycelia-Sterilia (1, 2, 3), based on their 5.8S ITS 1, ITS2 and partial 18S and 28S rDNA sequences were identified as Fusarium solani (99%), Chaetomium globosum (93%) and Chaetomium globosum (93%) respectively. Humicola, Drechslera, Colletotrichum, and Scytalidium sp. were some of the peculiar fungal endophytes recovered from this plant.
PMCID: PMC3209946  PMID: 23024409
Anti-microbial activity; Biodiversity; Fungal endophytes; Isolation media; Azadirachta indica
3.  Resolution of volatile fuel compound profiles from Ascocoryne sarcoides: a comparison by proton transfer reaction-mass spectrometry and solid phase microextraction gas chromatography-mass spectrometry 
AMB Express  2012;2:23.
Volatile hydrocarbon production by Ascocoryne sacroides was studied over its growth cycle. Gas-phase compounds were measured continuously with a proton transfer reaction-mass spectrometry (PTR-MS) and at distinct time points with gas chromatography-mass spectrometry (GC-MS) using head space solid phase microextraction (SPME). The PTR-MS ion signal permitted temporal resolution of the volatile production while the SPME results revealed distinct compound identities. The quantitative PTR-MS results showed the volatile production was dominated by ethanol and acetaldehyde, while the concentration of the remainder of volatiles consistently reached 2,000 ppbv. The measurement of alcohols from the fungal culture by the two techniques correlated well. Notable compounds of fuel interest included nonanal, 1-octen-3-ol, 1-butanol, 3-methyl- and benzaldehyde. Abiotic comparison of the two techniques demonstrated SPME fiber bias toward higher molecular weight compounds, making quantitative efforts with SPME impractical. Together, PTR-MS and SPME GC-MS were shown as valuable tools for characterizing volatile fuel compound production from microbiological sources.
PMCID: PMC3402149  PMID: 22480438
Biofuel; Solid phase microextraction; Proton transfer reaction-mass spectrometry; Volatile organic compounds; Fungal hydrocarbons; Gas chromatography-mass spectrometry
4.  3-Carbamoylquinoxalin-1-ium chloride 
The title compound, C9H8N3O+·Cl−, was isolated from a liquid culture of streptomyces sp. In the cation, the ring system makes a dihedral angle of 0.2 (2)° with the amide group. The protonation creating the cation occurs at ome of the N atoms in the quinoxaline ring system. In the crystal, the ions are linked through N—H⋯O and N—H⋯Cl hydrogen bonds, forming a two-dimensional network parallel to (10).
PMCID: PMC3254432  PMID: 22259578
5.  Bioactive Endophytes Warrant Intensified Exploration and Conservation 
PLoS ONE  2008;3(8):e3052.
A key argument in favor of conserving biodiversity is that as yet undiscovered biodiversity will yield products of great use to humans. However, the link between undiscovered biodiversity and useful products is largely conjectural. Here we provide direct evidence from bioassays of endophytes isolated from tropical plants and bioinformatic analyses that novel biology will indeed yield novel chemistry of potential value.
Methodology/Principal Findings
We isolated and cultured 135 endophytic fungi and bacteria from plants collected in Peru. nrDNAs were compared to samples deposited in GenBank to ascertain the genetic novelty of cultured specimens. Ten endophytes were found to be as much as 15–30% different than any sequence in GenBank. Phylogenetic trees, using the most similar sequences in GenBank, were constructed for each endophyte to measure phylogenetic distance. Assays were also conducted on each cultured endophyte to record bioactivity, of which 65 were found to be bioactive.
The novelty of our contribution is that we have combined bioinformatic analyses that document the diversity found in environmental samples with culturing and bioassays. These results highlight the hidden hyperdiversity of endophytic fungi and the urgent need to explore and conserve hidden microbial diversity. This study also showcases how undergraduate students can obtain data of great scientific significance.
PMCID: PMC2518837  PMID: 18725962
6.  Bioprospecting for Microbial Endophytes and Their Natural Products 
Endophytic microorganisms are to be found in virtually every plant on earth. These organisms reside in the living tissues of the host plant and do so in a variety of relationships, ranging from symbiotic to slightly pathogenic. Because of what appears to be their contribution to the host plant, the endophytes may produce a plethora of substances of potential use to modern medicine, agriculture, and industry. Novel antibiotics, antimycotics, immunosuppressants, and anticancer compounds are only a few examples of what has been found after the isolation, culture, purification, and characterization of some choice endophytes in the recent past. The potential prospects of finding new drugs that may be effective candidates for treating newly developing diseases in humans, plants, and animals are great.
PMCID: PMC309047  PMID: 14665674
7.  Guanosine Diphosphate-l-Fucose Glycopeptide Fucosyltransferase Activity in Corynebacterium insidiosum1 
Journal of Bacteriology  1973;115(2):668-672.
The biosynthesis of a phytotoxic glycopeptide of Corynebacterium insidiosum involves guanosine diphosphate-l-fucosyltransferase activity. This enzyme activity is most consistently associated with the cellular membranes fraction. The optimal pH for the transfer reaction is 7.5. The partially hydrolyzed toxin serves as an acceptor (primer) of l-fucose.
PMCID: PMC246298  PMID: 4199136
8.  Origin of Cyanide in Cultures of a Psychrophilic Basidiomycete1 
Journal of Bacteriology  1968;95(3):1094-1102.
An unidentified psychrophilic basidiomycete used valine and isoleucine as precursors to hydrocyanic acid (HCN). As probable intermediates in the pathway from valine and isoleucine two cyanogenic glucosides, linamarin and lotaustralin, were demonstrated in fungus cultures. The fungus contained two β-glucosidases and an oxynitrilase which, acting together, were capable of releasing cyanide from both linamarin and lotaustralin. The two β-glucosidases were purified and compared as to pH optimum, Michaelis constant, energy of activation, thermal stability, and substrate specificity. The products of methyl ethyl ketone cyanohydrin and acetone cyanohydrin dissociation by the oxynitrilase were demonstrated to be HCN together with methyl ethyl ketone and acetone, respectively. The oxynitrilase attacked aliphatic hydroxynitriles, but showed no activity on aromatic hydroxynitriles.
PMCID: PMC252136  PMID: 5651322

Results 1-8 (8)