QSAR study of phenolic compounds and their anti-DPPH radical activity by discriminant analysis.

Phenolic compounds (PCs) could be applied to reduce reactive oxygen species (ROS) levels, and are used to prevent and treat diseases related to oxidative stress. QSAR study was applied to elucidate the relationship between the molecular descriptors and physicochemical properties of polyphenol analogues and their DPPH radical scavenging capability, to guide the design and discovery of highly-potent antioxidant substances more efficiently. PubMed database was used to collect 99 PCs with antioxidant activity, whereas, 105 negative PCs were found in ChEMBL database; their molecular descriptors were generated with Python's Rdkit package. While the molecular descriptors significantly related to the antioxidant activity of PCs were filtered by t-test. The prediction QSAR model was then established by discriminant analysis, and the obtained model was verified by the back-substitution and Leave-One-Out cross-validation methods along with heat map. It was revealed that the anti-DPPH radical activity of PCs was correlated with the drug-likeness and molecular fingerprints, physicochemical, topological, constitutional and electronic property. The established QSAR model could explicitly predict the antioxidant activity of polyphenols, thus were applicable to evaluate the potential of candidates as antioxidants.

The Outlook of the Development of Innovative Products from Biocompatible Natural Spider Silk in the Beauty Thread-Lifting Industry.

Embedding thread lift rhytidectomy, also known as "thread lifting" in China, with the natures of simple operation, less trauma and quick recovery, is progressively used in clinical practice as a new technology of face lifting. Herewith, a brief introduction of the previous advances of thread lifting techniques and materials in the facial beauty industry, combined with the discussion on various types of sutures, common complications, and the site of actions were provided. The main limitations of present thread lifting material include: (1) the use of non-absorbable sutures is liable to cause allergies and a series of complications; (2) the absorbable sutures are easily degradation, and people need to reshape in a relatively short period. Therefore, the high biocompatible spider silk was proposed as a novel material of thread lifting suture and related devices, the advantages and preliminary achievements on spider silk were also addressed.

A Strategy for Quality Control of Vespa magnifica (Smith) Venom Based on HPLC Fingerprint Analysis and Multi-Component Separation Combined with Quantitative Analysis.

As a folk medicine of the Jingpo minority in Yunnan province, the venom of Vespa magnifica has been commonly used for the treatment of rheumatoid arthritis. Quality standardization of the wasp venom is a necessary step for its pharmaceutical research and development. To control the quality of the wasp venom, a method based on high-performance liquid chromatography (HPLC) was developed for chemical fingerprint analysis. In the chromatographic fingerprinting, chemometrics procedures, including similarity analysis (SA), hierarchical clustering analysis (HCA), and principal component analysis (PCA), were applied to classify 134 batches (S1-S134) of wasp venom from different origins. The HPLC fingerprint method displayed good precision (Relative standard deviation, RSD < 0.27%), stability (in 16 h, RSD < 0.34%), and repeatability (RSD < 1.00%). Simultaneously, four compounds (VMS1, VMS2, VMS3, and VMS4) in the wasp venom were purified and identified. VMS1 was 5-hydroxytryptamine, and the other compounds were three peptides that were sequenced as follows: Gly-Arg-Pro-Hyp-Gly-Phe-Ser-Pro-Phe-Arg-Ile-Asp-NH2 (VMS2), Ile-Asn-Leu-Lys-Ala-Ile-Ala-Ala-Leu-Ala-Lys-Lys-Leu-Leu-NH2 (VMS3), and Phe-Leu-Pro-Ile-Ile-Gly-Lys-Leu-Leu-Ser-Gly-Leu-Leu-NH2 (VMS4). The quantifications for these components were 110.2 mg/g, 26.9 mg/g, 216.3 mg/g, and 58.0 mg/g, respectively. The results of this work indicated that the combination of the chemical fingerprint and quantitative analysis offers a reasonable way to evaluate the quality of wasp venom.

Optimization of Ionic Liquid-Assisted Extraction of Biflavonoids from Selaginella doederleinii and Evaluation of Its Antioxidant and Antitumor Activity.

As new green solvents, ionic liquids (ILs) have been generally applied in the extraction and separation of natural product. In this study, microwave assisted extraction based on IL (IL-MAE) was firstly employed to extract total biflavonoids from Selaginella doederleinii. Based on single-factor experiment, microwave power (300-700 W), extract time (30-50 min) and extract temperature (40-60 °C) on total bioflavonoids and antioxidant activities of the extracts were further investigated by a Box-Behnken design of response surface methodology (RSM) selecting total bioflavonoids yields and IC50 of radical scavenging as index. Besides antioxidant activity of the extract was evaluated by a 2,2-diphenyl-1-picrylhydarzyl (DPPH) and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate (ABTS) radical scavenging assay, ferric reducing power assay and chelation of ferrous ions assay, and then anticaner activity was also researched against A549 cell line and 7721 cell line. The results illustrated that three factors and their interactions could be well suited for second-order polynomial models (p < 0.05). Through process parameters, optimization of the extract (460 W, 40 min, and 45 °C) and detection of bioactivity, the yield of total bioflavonoids was 16.83 mg/g and IC50 value was 56.24 µg/mL, respectively, indicating the extract has better anti-oxidation effect and antitumor activity. Furthermore, IL-MAE was the most efficient extracting method compared with MAE and Soxhlet extraction, which could improve extraction efficiency in a shorter time and at a lower temperature. In general, ILs-MAE was first adopted to establish a novel and green extraction process on the yields of total biflavonoids from S. doederleinii. In addition, the extract of containing biflavones showed potent antioxidant and anticancer capacity as a utilized valuable bioactive source for natural medicine.