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Background: Prosaikogenin F (PSF) has stronger anti-cancer bioactivity than saikosaponin A (SSA), however, it was hardly isolated due to its trace amount in the raw material of Radix Bupleuri (RB). In addition, the active chemical constituent was unstable under acidic conditions owing to a 13,28-epoxy-ether moiety at the D ring of its aglycone. Objectives: This study was to develop an appropriate method for obtaining acid-sensitive PSF from SSA abundant in RB. Materials and Methods: Enzymatic hydrolysis was employed and snailase was selected due to its good hydrolysis performance under nearly neutral circumstances. Hydrolysis conditions were then optimized by one-factor-at-a-time experimentation before response surface methodology (RSM) by Box-Behnken Design (BBD). Results: The reaction system was constructed in Na2HPO4-NaH2PO4 buffer (pH 6.0) containing snailase/SSA (44:1) at 39°C, then the hydrolysis lasted for 12 h. Therefore, the highest conversion ratio of SSA was achieved at 100.0%. Conclusion: The newly proposed method is eco-friendly for obtaining acid-sensitive PSF, which lays a solid foundation for its development to be an anti-cancer new drug. [ABSTRACT FROM AUTHOR]

Prosapogenin A is a secondary saponin in Dioscorea zingiberensis, and it showed remarkable pharmacological effects. Due to very low content and lack of well-developed biotransformation, its preparation was not efficient and clean. This study aims to establish an eco-friendly strategy for preparation of Prosapogenin A from plant material. Physical separation was employed to recycle starch and cellulose, and then D101 resin and polyamide packed-bed column was incorporated for purification of total steroidal saponins (TSS). After these pretreatments, purity of TSS was largely increased to 83.2% with recovery at 87.6%, which was subjected to enzymatic hydrolysis. Optimized reaction system was constructed in 0.20 M HAc-NaAc buffer (pH4.2) containing cellulase/TSS (3:1, w/w), and the hydrolysis was performed at 53 °C for 6 h. Consequently, TSS was almost completely hydrolyzed to Prosapogenin A, while the highest yield reached 5.62%. The newly proposed approach is promising for efficient preparation of Prosapogenin A in industrial applications. [ABSTRACT FROM AUTHOR]

Crystalline selenium, characterized by higher electronic conductivity and volumetric capacity, represents one of the most promising cathode materials for next-generation battery technologies. However, the notorious lithium polyselenide shuttle effects yield formidable challenges, causing overcharge problems and unsatisfactory cycle performances. In this work, a nanosheet on nanorod WSe2/WO2 heterostructure was firstly developed as a proof of concept to immobilize and catalyze the soluble lithium polyselenides species. Through an in situ selenization process, the W5O14–ethylenediamine nanorod precursor was transformed to the WSe2/WO2 heterostructure, which was composed of long WO2 nanorods and WSe2 nanosheets. A combination of visual adsorption/permeation experiments, Li2Se electrochemical deposition tests, and theoretical calculations unraveled the strong chemical anchoring and efficient re-utilization toward soluble Li2Se6 and Li2Se4 species on the as-designed WSe2/WO2 heterostructure, which can originate from the bridge-shaped interfacial bonding structure. As anticipated, Li–Se batteries based on WSe2/WO2 heterostructure-modified separator exhibited dramatically improved overcharge property (overcharge capacity is 28.3 mA h g−1, only 73.7% of that with pristine PP separator) and cycle performances (about 1.58 times higher than that with pristine PP separator). [ABSTRACT FROM AUTHOR]