Recognition on pharmacodynamic ingredients of natural products.

Natural products (NPs) play an irreplaceable role in the intervention of various diseases and have been considered a critical source of drug development. Many new pharmacodynamic compounds with potential clinical applications have recently been derived from NPs. These compounds range from small molecules to polysaccharides, polypeptides, proteins, self-assembled nanoparticles, and extracellular vesicles. This review summarizes various active substances found in NPs. The investigation of active substances in NPs can potentiate new drug development and promote the in-depth comprehension of the mechanism of action of NPs that can be beneficial in the prevention and treatment of human diseases.

Correction to: Runners' metabolomic changes following marathon.

[This corrects the article DOI: 10.1186/s12986-020-00436-0.].

Runners' metabolomic changes following marathon.

INTRODUCTION: Marathon, as a long-distance aerobic exercise, has become a fashionable or popular sport. However, little is known about the holistic metabolic changes occurring within the serum metabolome of athletes after the completion of a marathon. OBJECTIVES: The goal of current study was to have an in-depth understanding of the impact of marathon on human metabolomics as well as the relationships among a variety of metabolites. METHODS: The 20 studied subjects were all adult males who participated in a marathon. The serum samples of these participants were collected before and after the marathon and the biochemical metabolites in the serum were identified by an untargeted two-dimensional gas chromatography time-of-flight mass spectrometry. RESULTS: All participants completed the marathon within 3 h. Compared to those before exercise, serum urea and creatine kinase, as well as cortisol, elevated significantly (p < 0.05), whereas testosterone decreased significantly (p < 0.01). Metabolomic analysis showed that, compared to those before the competition, metabolites pyruvic acid, glyceric acid, malic acid, cis-aconitic acid, galacturonic acid, methyl fumaric acid, maltotriose, and others increased significantly after the competition (p < 0.05), but glucosamine and O-succinyl-L-homoserine decreased significantly (p < 0.05). Amino acid indexes, such as alanine, L-tyrosine and phenylalanine, increased significantly after exercise compared with those before exercise (p < 0.05), whereas serine, valine and asparagine decreased significantly (p < 0.05). Lipid metabolism indexes, glycerol, glyceric acid, octanoic acid, and quinic acid increased significantly (p < 0.05). Theophylline, xanthine and other indicators of caffeine metabolism increased significantly (p < 0.05). Furthermore, marathon performance, fat percentage, VO2max, and hemoglobin were correlated with the serum metabonomic indicators, so were serum testosterone and cortisol. CONCLUSION: These results illustrate that the metabolism of glucose and lipid of the athletes was enhanced following the marathon match. In addition, the metabolism of glucosamine was decreased and the metabolism of caffeine was increased. Our data provide new insights for marathon performance and nutritional status.

Sensitive colorimetric detection of Listeria monocytogenes based on isothermal gene amplification and unmodified gold nanoparticles.

Listeria monocytogenes (L. monocytogenes), one of most problematic food-borne bacteria, is mainly transmitted through the food chain and may cause listeriosis. Therefore, the development of rapid and sensitive L. monocytogenes detection technique has become an urgent task. In this study, we proposed a method using hyperbranching rolling circle amplification (HRCA) combined with gold nanoparticle (GNP) based colorimetric strategy to offer an isothermal, highly sensitive and specific assay for the detection of L. monocytogenes. First, a linear padlock probe targeting a specific sequence in the hly gene was designed and followed with a ligation by Taq DNA ligase. After ligation, further amplification by HRCA with a thiolated primer and an unlabeled primer is performed. The resulting thiolated HRCA products were then captured onto GNP surface and made GNP more salt-tolerant. Detection of the bacteria can be achieved by a facilitated GNP based colorimetric testing using naked eyes. Through this approach, as low as 100 aM synthetic hly gene targets and about 75 copies of L. monocytogenes can be detected. The specificity is evaluated by distinguishing target L. monocytogenes from other bacteria. The artificial contaminated food samples were also detected for its potential applications in real food detection. This method described here is ideal for bacteria detection due to its simplicity and high sensitivity.