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The present study reports the presence of a β-D-fructopyranosyl-(2→1)-linked fructan in nature for the first time, with a β-D-fructofuranosyl-(2→1)-linked fructan in a mixture from Codonopsis pilosula. High-performance gel permeation chromatography (HPGPC) shows that the molecule weights of these two fructans are 2.33 and 1.31 kDa. Their structures were analyzed by 1D and 2D NMR.

A new cycloartanyl ester, named codonopilate D (1), was isolated from the roots of Codonopsis pilosula (Franch.) Nannf. The structure of compound 1 was elucidated by extensive spectroscopic analysis including UV, IR, MS, and NMR data. Compound 1 exhibited the potential of inhibiting LPS-induced NO production in RAW 264.7 cells.

This study investigated the effect of flowing velocity and impact angle on the fluid-accelerated corrosion (FAC) of X65 pipeline steel in a wet CO2-containing environment by corrosion morphology analysis, electrochemical measurement, and hydromechanical numerical analysis. It has been found that the corrosion behavior was controlled by the ion diffusion rate and shear stress due to the flowing gas. With an increase in the flowing velocity, the pitting corrosion initially decreased and then increased when the flowing velocity exceeded 14 m/s; this increase is caused by the augmentation of shear stress. When the impact angle decreased, the position of serious corrosion gradually moved outwards.

This work investigated the flow-accelerated corrosion (FAC) behavior of 13Cr in a wet CO2-containing environment at different flowing gas velocities and impinging angles, with the natural-gas pipeline environment simulated by a self-assembled impingement jet system. Surface morphology determination, electrochemical measurements, and hydromechanics numerical analysis were carried out to study the FAC behavior. The results demonstrate that pitting corrosion was the primary mode of corrosion in 13Cr stainless steel. High-flow-rate gas destroyed the passive film and decreased the pitting potential, resulting in more serious corrosion. The corrosion degree with various impact angles showed the following order: 90° > 60° > 45°. The shear force and the electrolyte from the flowing gas were concluded to be the determinant factors of FAC, whereas the shear force was the main factor responsible for destroying the passive film.

The bioassay-oriented fractionation of mistletoe crude extracts (MCEE) using 75% ethanol and culture products of mistletoe transformed by Rhodobacter sphaeroides, a photosynthetic bacterium (PSBT), revealed that the high cytotoxic activities were due to the petroleum ether extracts (PEs) and the acid-precipitated proteins from the aqueous extracts (AQs) of MCEE and PSBT. The isolated triterpenes may account for the activities of the PEs of MCEE and PSBT, respectively. Extraction of MCEE using petroleum ether led to the isolation of 3-epi-betulinic acid (1), betulonic acid (2), oleanolic acid (3), and beta-amyrin acetate (4), while petroleum ether extraction of PSBT led to the isolation of 1,3,4,betulinic acid (5), erythrodiol (6), and (3beta)-olean-12-ene-3,23-diol (7). The PE of PSBT exerted higher cytotoxicity than the PE of MCEE, which was due to the different triterpene contents of these two extracts. The cytotoxic activities of all compounds were tested, and the results revealed that compounds 1, 2, 3, 5, 6, and 7 contributed significantly to the cytotoxicities of both PEs. The AQ of the PSBT exerted almost the same cytotoxic activity and lower toxicity compared to the AQ of the MCEE. These findings indicate that mistletoe products biotransformed by R. sphaeroides could be used to treat cancers, since they have lower toxicities and higher antitumor activities compared to standard treatments.