Irpexols A-C, xanthone derivatives from the endophyte fungus Irpex laceratus A878.

Three new xanthone derivatives irpexols A-C (1-3) and five known xanthones including three dimeric ones were successfully isolated from Irpex laceratus A878, an endophytic fungus of the family Irpicaceae from the medicinal plant Pogostemon cablin (Blanco) Bentham (Lamiaceae). The structures of these compounds were elucidated by extensive spectroscopic analyses including ultraviolet-visible spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS), and nuclear magnetic resonance (NMR). All of the three new compounds (1-3) share a de-aromatic and highly­oxygenated xanthone skeleton. In addition, the cytotoxic activity of compounds 1-8 were evaluated against SF-268, MCF-7, HepG2, and A549 tumor cell lines. The results revealed that compound 6 showed moderate cytotoxic activity with the IC50 values ranging from 24.83 to 45.46 µM, while the IC50 values of the positive control adriamycin was ranging from 1.11 to 1.44 µM.

Cytospotones A-D, four new polyketones from the endophytic fungus Cytospora sp. A879.

Three new α-pyrone derivatives cytospotones A-C (1-3) and a new cyclohexenone derivative cytospotone D (4) together with four known α-pyrones were isolated from the endophytic fungus Cytospora sp. A879 of Pogostemon cablin (Blanco) Benth. The structures of 1-4 were elucidated primarily by spectroscopic methods (1D, 2D NMR and HRESIMS), ECD spectra analyses, and ECD calculations. Furthermore, the four new compounds (1-4) were evaluated for their anti-inflammatory and α-glucosidase inhibitory activities. The results showed that compound 1 had moderate inhibitory effect on LPS-induced NO production in RAW 264.7 macrophages.

Theoretical investigation for the cycle reaction of N2O (x1∑+) with CO (1∑+) catalyzed by IrO(n)+ (n = 1, 2) and utilizing the energy span model to study its kinetic information.

The mechanisms of the reactions between N(2)O and CO catalyzed by IrO(n)(+) (n = 1, 2) have been investigated using B3LYP and CCSD(T) levels of theory. Spin inversion among three reaction profiles corresponding to the quintet, triplet, and singlet multiplicities was discussed by using spin-orbit coupling (SOC) calculations. The probability of electron hopping in the vicinity of the (MECP) has been calculated by the Landau-Zener-type model. The single P(1)(ISC) and double P(2)(ISC) passes estimated at MECP1(#) (SOC = 198.61 cm(-1)) are approximately 0.11 and 0.20, respectively. Important analysis and explanations were done using molecular orbital theory and natural bonding orbital (NBO). The energetic span (δE) model coined by Kozuch was applied in this cycle. The turnover frequency (TOF)-determining transition state (TDTS) and TDI (TOF-determining intermediate) were confirmed. Finally, TOF(IrO(+))/TOF(IrO(2)(+)) = 0.38 at 298 K.

[The production of gastrodin through biotransformation of p-hydroxybenzaldehyde by cell suspension culture of Datura stramonium].

AIM: To investigate the production of p-hydroxymethylphenol-beta-D-glucoside (gastrodin) through biotransformation by plant cell suspension cultures. METHODS: Using cell suspension cultures of Datura stramonium to convert the exogenous p-hydroxybenzaldehyde into gastrodin was conducted and the converted compounds were separated with a combination of multi-chromatography. Their chemical structures were determined on the basis of spectral analysis and chemical evidence. RESULTS: The conversion procedure of p-hydroxybenzaldehyde into gastrodin by Datura stramonium cell suspension cultures was established. The synthesized gastrodin (II) was isolated from the fermental liquor and identified by spectral analysis. At the same time, the p-hydroxybenzyl alcohol (I) converted through biotransformation of p-hydroxybenzaldehyde by cell suspension cultures of Datura stramonium was also isolated and identified. Two compounds were also isolated from the cell cultures and they were identified as beta-D-furanoallulose (III) and n-butyloxystyryl-beta-D-pyranoallulose (IV). CONCLUSION: Datura stramonium grown in suspension cultures can convert exogenous p-hydroxybenzaldehyde into the corresponding gastrodin.

[Production of gastrodin through biotransformation of p-hydroxybenzaldehyde by cell suspension cultures of Datura tatula L].

The conversion of exogenous p-hydroxybenzaldehyde to p-hydroxy-methyl-phenol-beta-D-glucoside (gastrodin) was studied by using cell suspension culture of Datura tatula L. The chemical structure of this synthesized gastrodin was identified based on the spectral analysis and chemical evidence. The conversion procedure of p-hydroxybenzaldehyde into gastrodin by D. tatula L. cell suspension cultures was established. The synthesized gastrodin (II) was isolated from the ferment liquor and identified by spectral analysis. At the same time, the p-hydroxybenzyl alcohol (I) converted through biotransformation of p-hydroxybenzaldehyde by cell suspension cultures of D. tatula L. was also isolated and identified. The efficiency of glucosylation of p-hydroxybenzaldehyde was remarkably enhanced by adding salicylic acid (0.1 mg/L) and keeping the lower pressure (0.001MPa) in 25L airlift loop bioreactor. The biotransformation of exogenous p-hydroxybenzaldehyde to gastrodin by cell suspension culture of D. tatula L. is a promising approach.