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Background: Lysimachia christinae Hance (LCH) is a traditional medicine used to treat gallstone disease and cholecystitis. Despite its known anti‐inflammatory and choleretic effects, its quality has not been extensively evaluated. Objective: In this study, we aimed to establish a reliable quality evaluation method for LCH via fingerprint, spectrum–effect relationship, and quantitative analyses of multicomponents by a single marker (QAMS). Methods: First, the fingerprints and anti‐inflammatory and choleretic activities of 14 LCH batches were determined. Then, the gray relation analysis method was used to analyze the peak areas of the fingerprint profile and pharmacodynamic data. Subsequently, the characteristic peaks were tentatively identified using high‐performance liquid chromatography‐quadrupole time‐of‐flight mass spectrometry. Finally, rutin was selected as the internal reference material, and QAMS was used to analyze the LCH components. Results: Pharmacodynamic experiments confirmed that LCH exerted anti‐inflammatory and choleretic effects. Moreover, 15 flavonoids related to the anti‐inflammatory and choleretic effects of LCH were identified. Notably, relative error percentage between the QAMS and external standard method was less than 5%. Conclusion: This study successfully established a comprehensive evaluation method for the qualitative and quantitative analyses of LCH. This article has two innovations: (1) The study confirmed the indicator chemical components that can reflect the anti‐inflammatory and choleretic effects of LCH and optimized the quality control indicators. (2) Based on the theory of QAMS, the study successfully established a rapid detection method for the indicator chemical components of LCH, effectively reducing inspection costs. [ABSTRACT FROM AUTHOR]

Background: Hawk tea, a medicinal and edible plant, has been consumed for thousands of years in Southwest China. To date, no unified food safety standard for Hawk tea has been established, and systematic research on the quality of Hawk tea is lacking. Objective: The aim of this study was to develop a comprehensive evaluation method for the quality of Hawk tea based on inclusions content, high‐performance liquid chromatography (HPLC) fingerprinting combined with the quantitative analysis of multiple components with a single marker (QAMS) method. Methods: The contents of total flavonoids, total phenols, total polysaccharides, and total protein were determined using the colorimetric method. An effective comprehensive evaluation method was established to classify the 16 batches of samples based on HPLC fingerprint analysis combined with similarity analysis (SA), hierarchical cluster analysis (HCA), principal component analysis (PCA), partial least‐squares discrimination analysis (PLS‐DA), and the QAMS method. Results: Flavonoids were the main chemical components of Hawk tea. The accuracy of the QAMS method was verified by comparing the calculated results with those of the external standard method (ESM). No significant differences were found between the two methods. Additionally, the fingerprint of Hawk tea was also established. Conclusion: The method established in this study can be used for the comprehensive quality evaluation of Hawk tea and can also provide a reference for the quality evaluation of other herbal medicines. The flavonoids were the main chemical components of Hawk tea. The accuracy of the QAMS method was verified by comparing the calculated results with those of the external standard method (ESM). No significant differences were found between the two methods. Additionally, the fingerprint of Hawk tea was also established. The method established in this study can be used for the comprehensive quality evaluation of Hawk tea and can also provide a reference for the quality evaluation of other herbal medicines. [ABSTRACT FROM AUTHOR]

The Improved Hattmann tube devce was used for ignitbn expetimenrs to invesfigate the fame propagation process and thermal rad'ation charactetistics of MgH2 dust explosion. A high-speed camera, thermal radiometers, and the infrared he--mal imager synchronous conrrol system were used to record the lame propagation, heat radiation lux change, and temperature change process of MgH2 dust, respectiveiy. The resulrs show that after Ignition, the MgH2 fame continues to expand to form a continuous combustion area and when it reaches the maximum, it begins to decay, and a discrete fame appears. When the mass concenrration is 150-1 000 g/m3, the maximum propagation hegght and the maximum propagation veiocity of the fame front reach 1 138 mm and 45 m/s, respectiveiy, at 750 g/m3. in addition, the maximum heat rad'ation lux of No. 3 above the fireball reaches 31. 7kW/m2, which is much higher than those of No. 1 and No. 2 on both tides. The temperature is highest in he fame center and gradually decreases around it. The highstemperature zone is concenrrated in he upper past of he fame. [ABSTRACT FROM AUTHOR]

The peritrophic membrane (PM) plays an important role in protecting insects. The PM proteins are important to determinate the formation and function of the PM. A new PM protein, named Lsti99, was identified from the PM of Loxostege sticticalis larvae by cDNA library screening. The full cDNA of Lsti99 is 1392 bp in length, contains an open reading frame (ORF) of 1245 bp that encodes a preprotein of 415 amino acid residues with a 17-amino acid signal peptide. The sequence of Lsti99 showed no homology to other known PM proteins. The recombinant Lsti99 was successfully expressed in insect cells (Sf9) using recombinant baculoviruses and was used to isolate the antibodies to Lsti99 from the polyclonal antiserum. Lsti99 was expressed mainly in the PM, but weaker bands could be detected in the head and integument as well. The Lsti99 protein could be separated from the PM complex by chitinase in vitro, but M2R did not show effect in vitro confirming the chitin-binding activity of Lsti99. The biochemical and physiological functions of Lsti99 in L. sticticalis require further investigation.

To explore the energy release characteristic of MgH2 dust, a modified 20L sphere explosion venting device was used to obtain its explosion pressure and flame propagation. The applicability of the current industrial dust explosion venting standard to the safety design of MgH2 explosion venting was analyzed. The results show that under airtight conditions, with the increase in dust concentration, the explosion pressure of MgH2 dust increases first and then decreases, which reaches the maximum at 750 g/m³ with an explosion index of 310. 5MPa ⋅ m/s. The venting pressure and flame duration are mainly affected by the MgH2 dust concentration. The duct has a restrictive influence on the venting. With the duct length growing from 30cm to 100 cm, the maximum pressure and the explosion pressure rise rate in the vessel increase by 5%o and 9%o, respectively. NFPA 68 design standard is more applicable to MgH2 dust explosion at 250, 500 and 1 000 g/m³ . At 750 g/m³, the predicted value of the standard is lower than the experimental value. Only through the existing general industrial dust explosion venting standards for MgH2 explosion safety design may have certain risks. [ABSTRACT FROM AUTHOR]

Salvadora persica L. (Sp) has been widely used as folk medicine. This study aimed to identify and assess the significant phenolics' antioxidant activities in young (S1) and old (S2) leaves of Sp. Six flavonoids; isoquercitrin, kaempferol-3-neohesperidoside, myricetin-3-galactoside, apigenin-O-hexoside, isorhamnetin and isorhamnetin-3-neohesperidoside, were identified for the first time in Sp leaves using LC-ESI-QTOF MS/MS analysis. The flavonoid-rich fraction obtained after purification of S1 (S1TF7) has the highest TFC (358.88 ± 0.12 mg rutin equivalent/g) and TPC (180.82 ± 0.82 mg gallic acid equivalent/g) and exhibits significant (p < 0.05) free-radical scavenging activity in DPPH(IC50% = 14.64 ± 0.29 µg/mL) and ABTS (IC50% = 200.41 ± 1.85 µg/mL) assays which was similar to Butylated hydroxytoluene (BHT) as a positive control (IC50% =12.94 ± 0.10 µg/mL and IC50% = 190.47 ± 8.93 µg/mL, respectively). Also, S1TF7 inhibits Lipopolysaccharide (LPS)-stimulated ROS production in raw-cell-264.7 with no significant toxicity at 200 µg/mL (p > 0.05). The study concludes that S1TF7 can serve as a mean to prevent oxidative diseases, and it merits further pharmacological investigations. [ABSTRACT FROM AUTHOR]

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