Kinetic Study of Glucosamine Production Using Aspergillus sydowii BCRC 31742 under Solid-State Fermentation.

In the present study, we aimed to obtain a high yield and productivity for glucosamine using a low-cost solid-state culture with Aspergillus sydowii BCRC 31742. The fermentation conditions, such as inoculum biomass, moisture content, and supplemental volume and mineral salt, were chosen to achieve high productivity of glucosamine (GlcN). When the initial supplemental volume used was 3 mL/g substrate, the yield and productivity of GlcN were 48.7 mg/gds and 0.69 mg/gds·h, respectively. This result will be helpful for the industrialization of the process.

Structurally diverse sesquiterpenoids and polyketides from a sponge-associated fungus Aspergillus sydowii SCSIO41301.

Five new compounds, including one bisabolane-type sesquiterpenoids, namely aspergillusene D (1), two new xanthones (2 and 3), and two new catecholderivatives (4 and 5), together with fourteen known compounds (6-19), were isolated and identified from the fungus Aspergillus sydowiiSCSIO 41,301 from the sponge Phakellia fusca. Their structures and absolute configurations were determined by extensive spectroscopic analysis and electronic circular dichroism (ECD) calculations. Most of the isolated compounds (1-3, and 6-19) were evaluated for their antiviral, cytotoxic, and antibacterial activities. Among them, new compounds 2 and 3 displayed obvious selective inhibitory activities against two influenza A virus subtypes, including A/Puerto Rico/8/34 (H1N1) and A/FM-1/1/47 (H1N1), with IC50 values ranging from 2.17 ±â€¯1.39 to 4.70 ±â€¯1.11 µM.

Biodegradation of the Organophosphate Trichlorfon and Its Major Degradation Products by a Novel Aspergillus sydowii PA F-2.

Trichlorfon (TCF) is an important organophosphate pesticide in agriculture. However, limited information is known about the biodegradation behaviors and kinetics of this pesticide. In this study, a newly isolated fungus (PA F-2) from pesticide-polluted soils was identified as Aspergillus sydowii on the basis of the sequencing of internal transcribed spacer rDNA. This fungus degraded TCF as sole carbon, sole phosphorus, and sole carbon-phosphorus sources in a mineral salt medium (MSM). Optimal TCF degradation conditions were determined through response surface methodology, and results also revealed that 75.31% of 100 mg/L TCF was metabolized within 7 days. The degradation of TCF was accelerated, and the mycelial dry weight of PA F-2 was remarkably increased in MSM supplemented with exogenous sucrose and yeast extract. Five TCF metabolic products were identified through gas chromatography-mass spectrometry. TCF could be initially hydrolyzed to dichlorvos and then be degraded through the cleavage of the P-C bond to produce dimethyl hydrogen phosphate and chloral hydrate. These two compounds were subsequently deoxidized to produce dimethyl phosphite and trichloroethanal. These results demonstrate the biodegradation pathways of TCF and promote the potential use of PA F-2 to bioremediate TCF-contaminated environments.