S-scheme heterojunction phthalocyanine/TiO2 photoelectrochemical sensor for innovative glutathione detection.

A novel photoelectrochemical sensor, employing an S-scheme heterojunction of phthalocyanine and TiO2 nanoparticles, has been developed to enable highly sensitive determination of glutathione. By integrating the favorable stability, environmental benignity, and electronic properties of the TiO2 matrix with the unique photoactivity of phthalocyanine species, the designed sensor presents a substantial linear dynamic range and a low detection limit for the quantification of glutathione. The sensitivity is attributed to efficient charge transfer and separation across the staggered heterojunction energy levels, which generates measurable photocurrent signals. Systematic variation of phthalocyanine content reveals an optimal composition that balances light harvesting capacity and electron-hole recombination rates. The incorporation of phosphotungstic acid (PTA) in sample preparation effectively minimizes interference from compounds like L-cysteine and others. Consequently, this leads to an improvement in accuracy through the reduction of impurity levels. Appreciable photocurrent enhancements are observed upon introduction of both oxidized and reduced glutathione at the optimized composite photoanode. Coupled with advantageous features of photoelectrochemical transduction such as simplicity, cost-effectiveness, and resistance to fouling, this sensor holds great promise for practical applications in complex biological media.

Rapid molecular identification of Rana dybowskii by species-specific primers.

Oviductus Ranae is the dried oviduct from Rana dybowskii, a forest frog species with medicinal, tonic, and cosmetic properties. Due to the high price and resource shortage, counterfeit varieties of Oviductus Ranae often appear in the market. However, traditional identification methods cannot accurately differentiate between Oviductus Ranae and its adulterants. In this study, a rapid molecular identification method has been established. The method involves extracting genomic DNA in just 30 s using filter paper purification, species-specific rapid polymerase chain reaction (PCR) amplification, and finally, fluorescence detection of the products. It can accurately identify Oviductus Ranae and its three common adulterants in about 30 min, making the process simple, fast, and highly specific.

Molecular Identification and Phylogenetic Analysis of the Traditional Chinese Medicinal Plant Kochia scoparia Using ITS2 Barcoding.

Kochia scoparia has high medicinal and economic value. However, with similar morphological features, adulterants and some closely related species of K. scoparia are increasingly sold in the medicinal markets, leading to potential safety risks. In this study, 128 internal transcribed spacer 2 (ITS2) sequences were collected to distinguish K. scoparia from its closely related species and adulterants. Then, sequence alignment, sequence characteristics analysis, and genetic distance calculations were performed using MEGA 6.06 software, and the phylogenetic trees were reconstructed using both MEGA 6.06 and IQ-Tree software. Finally, the secondary structure of ITS2 was modeled using the prediction tool in the ITS2 database. The results showed that ITS2 sequences of K. scoparia ranged in length from 226 to 227 bp, with a mean GC content of 55.3%. The maximum intraspecific distance was zero, while the minimum interspecific distance from closely related species and adulterants was 0.009 and 0.242, respectively. Kochia scoparia formed an independent clade in the phylogenetic trees, and its secondary structure exhibited enough variation to be separated from that of other species. In summary, ITS2 can be used as a mini-barcode for distinguishing K. scoparia from closely related species and adulterants. Its phylogenetic trees could illustrate the evolutionary process of K. scoparia in the Camphorosmeae. The phylogenetic results using ITS2 barcode further supported the internationally recognized revised classifications of Kochia and Bassia genera as a combined Bassia genus, together with the establishment of new genera Grubovia and Sedobassia, which we suggest is accepted by the Flora of China. Graphical abstract .

Novel SNP markers on ginsenosides biosynthesis functional gene for authentication of ginseng herbs and commercial products.

Panax ginseng and Panax quinquefolius have similar bioactive components and morphological characteristics, but they are known to have different medicinal values, high-sensitive and accurate method is expected to identify the sources of ginseng products and evaluate the quality, but with a huge challenge. Our established UHPLC-TOF/MS method coupled with orthogonal partial least squares discriminant analysis (OPLS-DA) model based on 18 ginsenosides was applied to discriminate the sources of raw medicinal materials in ginseng products, and nested PCR strategy was used to discover 6 novel single nucleotide polymorphism (SNP) sites in functional dammarenediol synthase (DS) gene for genetic authentication of P. ginseng and P. quinquefolius for the first time. OPLS-DA model could identify the sources of raw ginseng materials are real or not. SNP markers were applied to identify ginseng fresh samples as well as commercial products, and proved to be successful. This established molecular method can tell exact source information of adulterants, and it was highly sensitive and specific even when total DNA amount was only 0.1 ng and the adulteration was as low as 1%. Therefore, this study made an attempt at the exploration of new type SNP marker for variety authentication and function regulation at the same time, and the combination of chemical and molecular discrimination methods provided the comprehensive evaluation and authentication for the sources of ginseng herbs and products.

[Research progress in molecular pharmacognosy of Pogostemon cablin].

Molecular pharmacognosy( MP) is a new interdisciplinary science,which integrates the pharmacognosy and molecular biology,and focuses on the crude drugs' classification and identification,cultivation and protection,and production of active ingredients at the molecular level. Pogostemon cablin is one of the ten major southern medicines in China,MP research on this famous herb has developed on the basis of traditional research methods,and achieved certain results. This article summarized the MP research achievements of P. cablin in recent years,the prospect of this field is also discussed to provide references for the protection,development and utilization of P. cablin resources.

Rapid identification of Dendrobium officinale using Loop-Mediated Isothermal Amplification (LAMP) method.

Dendrobium officinale is not only an ornamental plant, but also a valuable medicinal herb that is widely used in traditional Chinese medicine. However, distinguishing D. officinale from other Dendrobium species is usually a difficult task. In this study, we developed a rapid identification protocol for D. officinale using the loop-mediated isothermal amplification (LAMP) method. A set of primers were specifically designed to detect a modified internal transcribed spacer region of D. officinale at 65 °C within 40 min after adding SYBR® Green I, which was used for the detection of D. officinale. Unlike commonly used adulterants, reaction mixtures containing D. officinale DNA changed from orange to green, and this color change was easily observed with the naked eye. Thus, this methodology can be used to accurately differentiate D. officinale from other Dendrobium species, is quick as all D. officinale samples were amplified within 40 min, and specific as samples of the adulterants were not amplified. The specificity of this LAMP-based method was confirmed by testing 17 samples of D. officinale and 32 adulterant samples from other Dendrobium species. This LAMP-based rapid identification method does not require expensive equipment or specialized techniques and can be used in field surveys for accurate and fast on-site identification.

Inactivation of Lactobacillus Virulent Bacteriophage by Thermal and Chemical Treatments.

The uses of thermal and chemical treatments were evaluated with respect to the inactivation of the Lactobacillus virulent bacteriophage P2. Thermal treatments consisted of heating the phage at 63, 72, and 90°C in three broth media: de Man Rogosa Sharpe broth, reconstituted skim milk, and Tris magnesium gelatin buffer. Chemical treatments evaluated were ethanol, isopropanol, sodium hypochlorite, and peracetic acid at various concentrations. Phage P2 was completely inactivated in 20 and 5 min at 72 and 90°C, respectively. Reconstituted skim milk and de Man Rogosa Sharpe broth provided optimum and minimum heat protection, respectively. Only sodium hypochlorite at 400 and 800 ppm completely inactivated the phage in 50 and 30 min, respectively. Treatment with 100% ethanol and isopropanol resulted in only a ca. 5.1-log reduction. Peracetic acid at the highest concentration used (0.45%) resulted in only a 1.40-log reduction of the phage within 60 min. These results provide additional data for establishing effective methods of controlling phage contamination in dairy and laboratory environments.