Herbal tea is widely consumed in Jianghua, a Yao autonomous county in Hunan Province, China, to prevent and treat diseases. The materials in herbal tea at the traditional medicinal markets at the Dragon Boat Festival remain unknown. The aims of the paper were (1) to specifically investigate the materials of herbal tea used by Yao nationalities in Hunan Province, (2) to record the most common and the culturally important medicinal plant species in the markets, and (3) to compare the medical plant tradition both used for herbal tea between the Jianghua and Lingnan regions. During 2016–2017, 215 vendors were interviewed at traditional medicinal markets at the Dragon Boat Festival in Jianghua to record plants used for herbal tea and to document traditional knowledge of their medicinal function, habitat, and conservation status. Bunches of medicinal plants were purchased to identify the species and to prepare voucher specimens. Cognitive salience (CS) based on free-lists and use value (UV) were calculated to analyze the cultural importance of medical plants; other quantitative methods (coefficient of similarity and chi-square analysis) were applied for comparison of herbal tea tradition between the Jianghua and Lingnan regions. A total of 169 species belonging to 66 families and 142 genera were recorded in herbal tea to treat health conditions in the study area. There were 30 health conditions that were recorded, with heat-clearing and detoxifying being the most common medicinal function, followed by treating rheumatism and promoting blood circulation. Of the 169 species, 97 were herbs. The whole plant was the most commonly used plant part in the preparation of herbal tea. According to the national evaluation criteria, three of these species are listed on “China’s red list” and registered as vulnerable (VU). By comparing the coefficient of similarity of herbal tea plants and the number of mentions for part(s) used in Jianghua and Lingnan, the medicinal plant tradition is different in two areas. Herbal tea in Jianghua reflects the cultural diversity of the Yao people and the plant diversity of the region. Future research on the safety, efficacy, and the adulterants of herbal tea are needed for sustainable utilization.

Based on the structures of natural products streptochlorin and pimprinine derived from marine or soil microorganisms, a series of streptochlorin derivatives containing the nitrile group were designed and synthesized through acylation and oxidative annulation. Evaluation for antifungal activity showed that compound 3a could be regarded as the most promising candidate—it demonstrated over 85% growth inhibition against Botrytis cinerea, Gibberella zeae, and Colletotrichum lagenarium, as well as a broad antifungal spectrum in primary screening at the concentration of 50 μg/mL. The SAR study revealed that non-substituent or alkyl substituent at the 2-position of oxazole ring were favorable for antifungal activity, while aryl and monosubstituted aryl were detrimental to activity. Molecular docking models indicated that 3a formed hydrogen bonds and hydrophobic interactions with Leucyl-tRNA Synthetase, offering a perspective for the possible mechanism of action for antifungal activity of the target compounds.

Fumonisin B₁ (FB₁) is a toxin produced by the metabolism of Fusarium oxysporum, which can cause serious effects on the nervous, respiratory, digestive, and reproductive systems of humans or animals; it is known as one of the highly toxic epidemic contaminants. Herein, we report the visual inspection of FB₁ using bipolar electrodes (BPEs) with an array-based electrochemiluminescence (ECL) platform. The sensor consists of a PDMS cover and a glass substrate containing an array of 10 ITO electrodes. A specific sensing interface was constructed on the cathode of the BPE, which could modulate the ECL reactions that occurred at the anode of BPEs. To amplify the ECL signal, methylene blue (MB)-encapsulated Zr-MOFs (MB@Zr-MOFs) were synthesized and immobilized on the cathode of the BPE, which could amplify the ECL signal at the anode. By coupling the cyclic amplification effect of the DNA walker and nicking endonuclease (Nb.BbvCI), the biosensor can realize the visual measurement of FB₁ in the range of 5 × 10⁻⁵~0.5 ng/mL. In addition, the developed biosensor was used to monitor the concentration of FB₁ in maize and peanut samples. The recoveries were in the range of 99.2%~110.6%, which demonstrated the good accuracy of the designed BPE-ECL biosensor for FB₁ assay in food samples.

Au particles are commonly used for deposition on the surface of a bipolar electrode (BPE) in order to amplify electrochemical and electrochemiluminescence (ECL) signal because of their excellent conductivity, biocompatibility, and large surface area. In this work, a closed BPE device was fabricated and Au particles were deposited on the two poles of a BPE via bipolar deposition. Results indicated that the electrochemical stability of Au film on the anode part of the BPE and the reduction of AuCl₄^– to Au on the cathode part of the BPE depended on the conductivity of the solution. The prepared Au–Au BPE exhibited a remarkable amplification effect on the ECL signal. Then, a specific sensing interface was constructed on one pole of the BPE for the visual detection of prostate-specific antigens (PSA) based on sandwich-type immunoreactions between primary PSA antibodies (Ab₁) on the electrode surface, PSA, and SiO₂ nanoparticles labeled secondary PSA antibodies (SiO₂-Ab₂). The designed biosensor exhibited a good linear relationship for the ECL detection of PSA in the range of 1 × 10⁻⁶ to 1 × 10⁻¹⁰ g/mL with a correlation coefficient of 0.9866; the limit of detection (LOD) was 1.5 × 10⁻¹¹ g/mL. Additionally, the biosensor can realize the electrochemical imaging of PSA by regulating the electrochemical oxidation of the Au anode with the immunoreactions on the cathode part of BPE. Therefore, the small, portable and highly sensitive biosensors have great potential for on-site detection.

Peroxynitrite (ONOO⁻) has been revealed to play crucial roles in many physiological and pathological processes, and many diseases were proven to be associated with its misregulated production. The development of fluorescent probes meets the need for tracking ONOO⁻ and gives a better understanding of its diverse mechanisms. In this work, a red-emitting fluorescent probe BP-ONOO was synthesized via functionalization of the rhodol-like fluorophore with a reactive site of hydrazide. The probe BP-ONOO exhibited high sensitivity, excellent selectivity, and short response time (less than 4 s) towards ONOO⁻ under neutral or weak alkaline conditions. These attractive properties favor its application in real-time imaging of ONOO⁻ in living cells, and the probe has been successfully applied for imaging the concentration levels of ONOO⁻ in RAW 264.7 macrophage cells under drug stimulation.