Quality Evaluation of Traditional Chinese Medicine Mylabris Based on Heavy Metal Risk Assessment and Analysis of Pharmacological Component Contents.

As a highly representative traditional Chinese anti-tumor medicinal material, the biomass of Mylabris is collected from the wild. However, the living environments of Mylabris is differ, so Mylabris may be contaminated by heavy metal pollution depending on the environment. These environments may also affect the amount of biosynthesis of its medicinal ingredient, cantharidin, there by affecting the quality of Mylabris. In this study, we determined the heavy metal content in Mylabris from different origins by using ICP-MS, evaluated the risk posed by these heavy metals, and recommended theoretical maximum limits of heavy metals in medicinal Mylabris. The results show that the Cu content in Mylabris is substantially higher than that in Cr, As, Pb, Cd, and Hg. A quantitative risk assessment showed that Mylabris poses no noncarcinogenic risks. The results of the total carcinogenic risk value showed that origins S12 and S13 pose carcinogenic risk by Cr and As, and the rest of the origins were in the human-tolerable carcinogenic risk range. We found large differences in the cantharidin content in Mylabris from different origins. In general, the Mylabris from origins S2, S3 and S4 had a higher in vivo cantharidin content, which proved that the quality of the medicinal materials was higher here than in other production areas. Finally, we providing a reference for the quality evaluation of medicinal Mylabris materials.

Heavy Metal Pollution Analysis and Health Risk Assessment of Two Medicinal Insects of Mylabris.

Mylabris is the dried body of the Chinese blister beetle (Mylabris sp.), which has been used in traditional Chinese medicine and achieved significant positive effects in the treatment of cancer including liver cancer, lung cancer, and rectal cancer. However, heavy metal pollution and accumulation of Mylabris insects could pose threat to human health. This study was carried out to assess levels of different heavy metals like Cu, As, Cd, Hg, and Pb, along with soil-plant-insect system and health risks using two representative Mylabris insects from the Hasi Mountains of Gansu Province, China. The results showed that the heavy metal concentration of plants and insects followed the order Cu > Pb > As > Hg > Cd. Compared with soil and plants, the content of Cu in insects was the highest, reaching 45.65 mg/kg. Cu was the main element that caused insects to absorb and accumulate. The quantitative risk analysis implied the two Mylabris insects had carcinogenic risks, with the contribution of As providing 63% and 60.7%, respectively. This kind of carcinogenic risk that the human body could bear was not easy to cause side effects to normal people, but it was difficult and dangerous for cancer patients. Thus, the evaluation of health risk lays the foundation for pollutant risk monitoring.

PEGylated dihydromyricetin-loaded nanoliposomes coated with tea saponin inhibit bacterial oxidative respiration and energy metabolism.

The biofilms produced by the aggregation of bacterial colonies are among the major obstacles of host immune system monitoring and antimicrobial treatment. Herein, we report PEGylated dihydromyricetin-loaded liposomes coated with tea saponin grafted on chitosan (TS/CTS@DMY-lips) as an efficient cationic antibacterial agent against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), which is supported by their deep penetration into bacterial biofilms and broad pH-stable release performance of dihydromyricetin (DMY). The successful construction of the drug delivery system relied on tea saponin grafted on chitosan (TS/CTS) via formatted ester bonds or amido bonds as a polyelectrolyte layer of PEGylated dihydromyricetin-loaded liposomes (DMY lips), which achieved controlled release of DMY in weak acidic and neutral physiological environments. The micromorphology of TS/CTS@DMY-lips was observed to resemble dendritic cells with an average size of 266.49 nm, and they had excellent encapsulation efficiency (41.93%), water-solubility and stability in aqueous solution. Besides, TS/CTS@DMY-lips displayed effective destruction of bacterial energy metabolism and cytoplasmic membranes, resulting in the deformation of the cell wall and leaking of cytoplasmic constituents. Compared to free DMY, DMY lips and chitosan-coated dihydromyricetin liposomes (CTS@DMY-lips), TS/CTS@DMY-lips has more thorough killing activity against E. coli and S. aureus, which is related to its excellent sustained release performance of DMY under the protection of the TS/CTS coating.