The Research Progress of Bioactive Peptides Derived from Traditional Natural Products in China.

Traditional natural products in China have a long history and a vast pharmacological repertoire that has garnered significant attention due to their safety and efficacy in disease prevention and treatment. Among the bioactive components of traditional natural products in China, bioactive peptides (BPs) are specific protein fragments that have beneficial effects on human health. Despite many of the traditional natural products in China ingredients being rich in protein, BPs have not received sufficient attention as a critical factor influencing overall therapeutic efficacy. Therefore, the purpose of this review is to provide a comprehensive summary of the current methodologies for the preparation, isolation, and identification of BPs from traditional natural products in China and to classify the functions of discovered BPs. Insights from this review are expected to facilitate the development of targeted drugs and functional foods derived from traditional natural products in China in the future.

Systemic chemical characterization of Lemna minor by UHPLC-Q-Exactive Orbitrap MS coupled with parallel reaction monitoring.

Lemna minor L. (LM) has been used for measles opacity, rubella itching, edema, and oliguria, and the main active ingredients were flavonoids, namely, apigenin, apigenin-7-O-glucoside, and luteolin-7-O-glucoside. However, few systematic analyses of their constituents have been performed; thus, it was necessary to establish a fast and efficient method to identify the chemical composition of LM. In this study, the UHPLC-Q-Exactive Orbitrap mass spectrometry coupled with parallel reaction monitoring was established. Finally, a total of 112 constituents, including 30 dipeptides, 28 nucleosides, 11 amino acids, 10 organic acids, 10 flavonoids, and 23 other compounds, were identified by MS, diagnostic fragment ions, and retention time. One hundred one of those chemicals were first found in LM, which was very beneficial for the further development and utilization of nutriments and the medicinal use of LM.

Screening and characterization estrogen receptor ligands from Arnebia euchroma (Royle) Johnst. via affinity ultrafiltration LC-MS and molecular docking.

Arnebiae Radix (dried root of Arnebia euchroma (Royle) Johnst.) is a traditional Chinese medicine (TCM) used to treat macular eruptions, measles, sore throat, carbuncles, burns, skin ulcers, and inflammations. The Arnebiae Radix extract can exert anti-breast cancer effects through various mechanisms of action. This study aimed to rapidly screen potential estrogen receptor (estrogen receptor α and estrogen receptor ß) ligands from the Arnebiae Radix extract. In this study, an analytical method based on affinity ultrafiltration coupled with UHPLC-Q-Exactive Orbitrap mass spectrometry was established for rapidly screening and identifying estrogen receptor ligands. Then, bindings of the components to the active site of estrogen receptor (estrogen receptor α and estrogen receptor ß) were investigated via molecular docking. Moreover, surface plasmon resonance (SPR) experiments with six compounds were performed to verify the affinity. As a result, a total of 21 ligands were screened from Arnebiae Radix using affinity ultrafiltration. Among them, 14 and 10 compounds from Arnebiae Radix showed affinity with estrogen receptor α and estrogen receptor ß, respectively. All of those ligands could have a good affinity for the multiple amino acid residues of the estrogen receptor based on molecular docking. In addition, six compounds display the great affinity by SPR. The method established in the study could be used to rapidly screen estrogen receptor ligands in Traditional Chinese medicine. The results demonstrated that the affinity ultrafiltration-UHPLC-Q-Exactive Orbitrap mass spectrometry method not only aids in the interpretation of the potential bioactive components and possible mechanisms of action of Arnebiae Radix but also provides a further effective basis for the quality control of this valuable herb medicine.

Easy fabrication and resistivity-temperature behavior of an anisotropically conductive carbon nanotube-polymer composite.

An easy fabrication method comprising a slit die extrusion-hot stretch-quench process was used to make carbon nanotubes (CNTs) filled with anisotropically conductive polymer composite (ACPC). CNTs were first premixed with polycarbonate (PC) by coagulation and then melt mixed with polyethylene (PE). During extrusion, the CNT/PC/PE composite was subjected to hot stretching to make the CNT/PC phase form in situ an oriented conductive fibril assembly in the PE matrix. Finally the aligned CNT/PC short fibrils were quenched to preserve their structure. The resultant CNT/PC/PE composite exhibited strong anisotropy in conductivity. This method has the advantages of giving a highly oriented structure with good control of electrical anisotropy as well as the ability to be fabricated in a high rate manner. Temperature-resistivity behavior was investigated by observing the resistivity during isothermal treatment (IT) as well as nonisothermal treatment (NIT). Percolation behavior was seen in the isolated direction during the first IT at 180 degrees C. This was a result of a disordering-induced conductive network. In addition, the positive temperature coefficient (PTC) effect attenuated with IT duration. This was seen in contrast to the remaining negative temperature coefficient (NTC). The unique evolution of PTC and NTC effects originated from the ACPC's special conductive network. It can be seen that this is composed of the originally connected "intrinsic pathway" and isolated "potential pathway".