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8. Chemical constituents and their anti-inflammatory activities from the roots of Ardisia crenata var. bicolor

Author

YE Hongbo, ZHOU Yongqiang, LIAO Zhangrong, WEI Xin, YIN Xin, LI Jiaxin, and ZHOU Ying

Subjects
ardisia crenata var. bicolor root, chemical constituents, isolation and purification, structure identification, bergenin, anti-inflammatory activity, Botany, QK1-989
Abstract

Ardisia crenata var. bicolor is a common medicine used by Miao Minority in Guizhou, which has the effects of clearing throat and benefiting pharynx, reducing swelling and relieving pain, dispelling wind and dehumidifying. In order to study the chemical constituents and anti-inflammatory activities of A. crenata var. bicolor roots, the 70% ethanol extact was separated and purified by silica gel column chromatography, Sephadex LH-20 gel column chromatography, ODS reverse column chromatography and semi-preparative HPLC. The structures of the compounds were identified by spectral data of NMR, MS and published literatures. Using lipopolysaccharide (LPS)-activated RAW 264.7 cell line model in vitro, compounds 1-4 were evaluated for the inhibition against nitric oxide (NO) production. The results were as follows: (1) Ten compounds were isolated from the 70% ethanol extract and identified as 11-O-galloylbergenin (1), 11-O-(4-O-methylgalloyl) bergenin (2), 11-O-vanilloylbergenin (3), 6-O-(4-hydroxy benzoyl) bergenin (4), 11-syringylbergenin (5), 11-O-(3′,4′-dimethylgalloyl)-bergenin (6), demethoxybergenin (7), micractinin A (8), monomethyl olivetol (9), and dibutyl phthalate (10). Among them, compounds 4, 8, 9 were obtained from Ardisia for the first time. (2) The results of anti-inflammatory activities in vitro showed that compounds 1-4 could significantly inhibit NO release in RAW 264.7 cells (P

Published
2024
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46. A two-dimensional lead-free double perovskite for self-powered and high performance X-ray detection.

Author

Zhou, Yongqiang, Huang, Lei, Wu, Mengyue, Kuang, Faguang, An, Kang, Feng, Peng, He, Peng, Pu, Yayun, Lai, Jun'an, and Tang, Xiaosheng

Abstract

Two-dimensional Dion–Jacobson (DJ) phase hybrid perovskites are gradually coming to the stage of optoelectronic devices because of their excellent photoelectric properties. These materials exhibit broad application potential in various fields such as solar cells, light-emitting diodes (LEDs), and X-ray detection. Specifically, DJ phase hybrid perovskites are often promising in direct X-ray detection. Herein, a new lead-free DJ-phase layered perovskite, (HA)2AgBiBr8 (HA2+ = histammonium), single crystal was examined. This newly developed material exhibits excellent semiconductor properties for direct X-ray detection, including high resistivity (8.03 × 1010 Ω cm), a low trap state density (1.1648 × 1011 cm−3), and a large mobility–lifetime value (2.047 × 10−3 cm2 V−1). Notably, the (HA)2AgBiBr8 based X-ray detector performed outstandingly in terms of radiation-to-current response, showing a fast response time (rise time: 21.8 ms, fall time: 42.7 ms). It demonstrated self-powered character, showing a high sensitivity of 252.38 μC Gyair cm−2 and low detection limit of 68.9 nGyair s−1 at 3.10 V mm−1. In addition, the as-fabricated device exhibits excellent imaging performance and long-term stability during X-ray imaging. This work provides a feasible path for the innovative application of organic–inorganic hybrid lead-free perovskites in medical diagnosis and efficient X-ray detection. [ABSTRACT FROM AUTHOR]

Published
2024
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48. Pickering emulsions based on ovalbumin‐ferulic acid‐sodium alginate supramolecular hydrogels: application to cookies replacing margarine.

Author

Xie, Bing, Xin, Ting, Huang, Yunying, Liu, Zhigeng, Jin, Weihao, Tao, Chunlan, Zhou, Yongqiang, Dong, Lihong, Huang, Fei, and Su, Dongxiao

Subjects
TRANS fatty acids, CORN oil, FAT substitutes, SURFACE cracks, POLYSACCHARIDES, FERULIC acid
Abstract

Summary: Margarine contains trans fatty acids, which have been linked to adverse effects on human health. It is therefore of the utmost importance to develop superior margarine substitutes for use in baked foods. The protein‐polyphenol‐polysaccharide ternary supramolecular system displays remarkable stability and can be utilised in the formulation of emulsions for partial margarine replacement. The aim of this study was to examine the stability of an ovalbumin (OVA)‐ferulic acid (FA)‐sodium alginate (SA) ternary supramolecular emulsion with varying water‐to‐oil ratios. The emulsion was evaluated for its potential as a substitute for margarine in cookies. The findings revealed that the specific emulsion instability of the system initially increased and subsequently decreased with an increase in corn oil content, reaching an optimal point of stability and dispersibility at a water‐to‐oil ratio of 5:11. As the emulsion was incorporated into the cookie dough at levels ranging from 0% to 100% margarine, the viscoelasticity of the dough was enhanced and the hardness was reduced. As the emulsion content increased in place of margarine, the cookies exhibited visible cracks on the surface, accompanied by an increase in hardness, baking loss rate and a notable change in colour. The cookies demonstrated the optimal quality when the emulsion content was 40%. [ABSTRACT FROM AUTHOR]

Published
2024
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49. Parameter estimation for fractional-order nonlinear systems based on improved sparrow search algorithm.

Author

Zhou, Yongqiang, Yang, Renhuan, Chen, Yibin, Huang, Qidong, Shen, Chao, Yang, Xiuzeng, Zhang, Ling, and Wei, Mengyu

Subjects
*METAHEURISTIC algorithms, *OPTIMIZATION algorithms, *PARAMETER estimation, *SEARCH algorithms, *PARTICLE swarm optimization
Abstract

Parameter estimation is important in the study of control and synchronization of fractional-order nonlinear systems (FONSs). This paper proposes an improved Sparrow Search Algorithm (ISSA) for the parameter estimation problem of FONSs. The algorithm improves the population initialization, position update method of discoverers and warning sparrows based on Sparrow Search Algorithm (SSA), and the parameter estimation simulation experiment for fractional-order financial nonlinear system and fractional-order L nonlinear system is conducted to demonstrate this method. The experimental results show that the proposed ISSA is superior to the SSA, Particle Swarm Optimization (PSO), Whale Optimization Algorithm (WOA) and Harris Hawks Optimization (HHO) in terms of parameter optimization accuracy and convergence speed, which validates the advantages of the ISSA. [ABSTRACT FROM AUTHOR]

Published
2024
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