Simultaneous quantitative analyses of Tanshinone I, Cryptotanshinone, and Tanshinone IIA in Danshen (Salvia miltiorrhiza Bunge) cultivated in Vietnam using LC-MS/MS

By using chromatography methods, the principal compounds tanshinon I, cryptotanshinone, tanshinone IIA were isolated from danshen (Salvia miltiorrhiza Bunge). Based on the spectroscopic data (1H-NMR, 13C-NMR and ESI-MS mass spectra), the structures were determined. The compound was purified (purity > 99.8%) by Agilent 218 purification system, which was used as the standard for analyzing tanshinon I, cryptotanshinone, tanshinone IIA in six samples. In this study, one LC-MS/MS method was developed for the simultaneous quantitative determination of three bioactive principles, tanshinone I, cryptotanshinone, and tanshinone IIA in Radix Salviae miltiorrhizae (RSM, the root of S. miltiorrhiza). The quantification of these diterpenoids is based on the fragments of [M+H]+ under collision-activated conditions and in selected reaction monitoring (SRM) mode. The quantitative method is validated by determining the mean recovery from fortified samples of tanshinone I, cryptotanshinone, and tanshinone IIA as higher than 98%. The established method is successfully applied to the quality assessment of six batches of RSM samples collected from different regions of Vietnam. The results show that Lam Dong sample has the highest tanshinone I content (4.4286±0.0009 µg/mg), meanwhile Muong Long sample has the lowest (1.2717±0.0013µg/mg). Lam Dong sample has the highest cryptotanshinone content (8.1589±0.0006 µg/mg), whereas Guangxi-China sample has the lowest (2.8630±0.0008 µg/mg). Ha Giang sample has the highest tanshinone IIA content (13.0252±0.0004 µg/mg), whereas Muong Long sample has the lowest (3.8278±0.0003 µg/mg)

Simultaneous quantitative analyses of Tanshinone I, Cryptotanshinone, and Tanshinone IIA in Danshen (Salvia miltiorrhiza Bunge) cultivated in Vietnam using LC-MS/MS

74-83By using chromatography methods, the principal compounds tanshinon I, cryptotanshinone, tanshinone IIA were isolated from danshen (Salvia miltiorrhiza Bunge). Based on the spectroscopic data (1H-NMR, 13C-NMR and ESI-MS mass spectra), the structures were determined. The compound was purified (purity > 99.8%) by Agilent 218 purification system, which was used as the standard for analyzing tanshinon I, cryptotanshinone, tanshinone IIA in six samples. In this study, one LC-MS/MS method was developed for the simultaneous quantitative determination of three bioactive principles, tanshinone I, cryptotanshinone, and tanshinone IIA in Radix Salviae miltiorrhizae (RSM, the root of S. miltiorrhiza). The quantification of these diterpenoids is based on the fragments of [M+H]+ under collision-activated conditions and in selected reaction monitoring (SRM) mode. The quantitative method is validated by determining the mean recovery from fortified samples of tanshinone I, cryptotanshinone, and tanshinone IIA as higher than 98%. The established method is successfully applied to the quality assessment of six batches of RSM samples collected from different regions of Vietnam. The results show that Lam Dong sample has the highest tanshinone I content (4.4286±0.0009 µg/mg), meanwhile Muong Long sample has the lowest (1.2717±0.0013µg/mg). Lam Dong sample has the highest cryptotanshinone content (8.1589±0.0006 µg/mg), whereas Guangxi-China sample has the lowest (2.8630±0.0008 µg/mg). Ha Giang sample has the highest tanshinone IIA content (13.0252±0.0004 µg/mg), whereas Muong Long sample has the lowest (3.8278±0.0003 µg/mg)

Potential application of rhizobacteria isolated from the Central Highland of Vietnam as an effective biocontrol agent of robusta coffee nematodes and as a bio-fertilizer

[[abstract]]Robusta coffee is a major commercial crop in the Central Highland of Vietnam with high economic and export value. However, this crop is adversely affected by various pathogens, particularly nematodes. This study aimed to screen active anti-nematode rhizobacterial strains for sustainable coffee production. Among more than 200 isolates, the isolate TUN03 demonstrated efficient biocontrol with nearly 100% mortality of J2 coffee nematodes Meloidogyne spp. and 84% inhibition of nematode egg hatching. This active strain was identified as Pseudomonas aeruginosa TUN03 based on its 16S rRNA gene sequence and phylogenetic analysis. In greenhouse tests, the strain TUN03 significantly reduced the coffee nematode population in the rhizome-soil with an 83.23% inhibition rate and showed plant growth-promoting effects. Notably, this is the first report of the nematicidal effect of P. aeruginosa against coffee nematodes. This potent strain further showed an antifungal effect against various crop-pathogenic fungi and was found to be the most effective against Fusarium solani F04 (isolated from coffee roots) with a 70.51% inhibition rate. In addition, high-performance liquid chromatography analysis revealed that this bacterial strain also secretes plant growth regulators including indole acetic acid (IAA), gibberellic acid (GA3), kinetin, and zeatin in significant amounts of 100, 2700, 37, and 9.5 µg/mL, respectively. The data from this study suggest that P. aeruginosa TUN03 may be a potential biocontrol agent and biofertilizer for the sustainable production of Robusta coffee and other crops.[[sponsorship]]科技部[[notice]]補正完

Application of Multiwalled Carbon Nanotube Nanofluid for 450 W LED Floodlight

Overheating of the high-power light emitting diode (LED) has a dramatic effect on the chip’s lifetime. Heat dissipation for high-power LED is becoming a major challenge for researchers and technicians. Compared with the air cooling method, the liquid cooling method has many advantages and high efficiency because of higher specific heat capacity, density, and thermal conductivity. Carbon nanotubes with remarkable thermal properties have been used as additives in liquids to increase the thermal conductivity. In this work, multiwalled carbon nanotubes nanofluid (MWCNTs nanofluid) was used to enhance heat dissipation for 450 W LED floodlight. MWCNTs nanofluid was made by dispersing the OH functionalized MWCNTs in ethylene glycol/water solution. The concentration of MWCNTs in fluid was in the range between 0.1 and 1.3 gram/liter. The experimental results showed that the saturated temperature of 450 W LED chip was 55°C when using water/ethylene glycol solution in liquid cooling system. In the case of using MWCNTs nanofluid with 1.2 gram/liter of MWCNTs’ concentration, the saturated temperature of LED chip was 50.6°C. The results have confirmed the advantages of the MWCNTs for heat dissipation systems for high-power LED floodlight and other high power electronic devices

Taming electromagnetic metamaterials for isotropic perfect absorbers

Conventional metamaterial absorbers, which consist of a dielectric spacer sandwiched between metamaterial resonators and a metallic ground plane, have been inherently anisotropic. In this paper, we present an alternative approach for isotropic perfect absorbers using symmetric metamaterial structures. We show that by systematically manipulating the electrically and magnetically induced losses, one can achieve a desired absorption without breaking the structural homogeneity. Finite integration simulations and standard retrieval method are performed to elaborate on our idea

Microstructure and luminescence of VO2 (B) nanoparticle synthesis by hydrothermal method

This paper reports the way for the synthesis of nanoplate VO2 (B) particles with controlled morphology. Nanoplate VO2 (B) particle was synthesized by hydrothermal method. Microstructure of VO2 (B) particles were controlled by hydrothermal temperatures and use of Zn doping into VO2 (B) matrix. The microstructure of the particles was shifted from nanowires to nanoplate morphology by changing of hydrothermal temperatures. The doping of Zn into VO2 nanoparticles resulted in an effective achievement of VO2 (B) phase. In addition, luminescence of VO2 (B) nanoparticle was also controlled by the use Zn doping. These results suggest that the potential application of Zn doped VO2 (B) particles for potential application in optical and energy techniques

Chemical constituents from the fruiting bodies of <i>Phellinus igniarius</i>

<p>A new tirucallane-type triterpenoid igniarine (<b>1</b>), and four known compounds meshimakobnol A (<b>2</b>), meshimakobnol B (<b>3</b>), ergosterol (<b>4</b>) and ergosterol peroxide (<b>5</b>), were purified from the methanol extracts of the fruiting bodies of <i>Phellinus igniarius</i> (DC. ex Fr.) Quél. The structure of <b>1</b> was elucidated using a combination of 1D and 2D NMR techniques and HR-ESI-MS analyses. In addition, the isolated compounds were examined for their cytotoxicity against several tumour cell lines and part of the tested compounds demonstrated weak cytotoxicity.</p