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1.
Heliyon ; 9(1): e12696, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36685425

RESUMO

Heated tobacco products (HTPs) are a novel type of cigarette that have received extensive attention. The tobacco plug could be made from tobacco granules (TGs), which are heated but not burned during the inhalation process. Thermal conductivity is an important property to evaluate the speed of heating TGs to meet the critical temperature for generating aerosol. Nevertheless, thermal physics properties of TGs is rarely reported. In this study, the thermophysical performance for the tobacco granules is systematically studied. An effective strategy of raising the thermal conductivity of TGs by introducing a small amount of nanoparticles of high-thermal-conductivity-materials (HTCMs, copper, silver, and graphene) is proposed, which not only results in a 35% improvement in the thermal conductivity but also reduces the maximum temperature for generating aerosol. In addition, introducing Cu and Ag particles in the TGs are favorable for improving the antibacterial effect. This method is worth promoting for enhancing the thermal conductivity of other plant-derived heated products.

2.
J Sep Sci ; 43(8): 1603-1613, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32034866

RESUMO

In order to determine six alkaloids (mass fraction) of nicotine, nornicotine, myosmine, anatabine, anabasine, and nicotyrine in tobacco and tobacco products quickly, accurately, and simultaneously, a novel method based on direct analysis of real-time model in situ ionization technique combined tandem mass spectrometry with a modified sample pretreatment was established, in which experimental parameters such as the type and amount of extraction solvent and injection rate were optimized, respectively. The samples of five commercial cigarettes and five kinds of tobacco leaves were analyzed by the established method, and the determined values were compared with those obtained using a gas chromatography with mass spectrometry method: (1) Under optimized conditions (30 mL ultrapure water as extraction solvent and with extraction rate of 0.6 mm/s), analysis could be completed within 10 min. (2) The linear range of the method was 0.002-2000 µg/g with R 2 = 0.9957 , the recovery ranged from 86.8 to 105.6%, and the limit of detection and the limit of quantification were 0.004-0.835 µg/g and 0.013-2.787 µg/g, respectively. (3) The relative standard deviation between direct analysis of real-time method and the gas chromatography with mass spectrometry method was 0.34-8.83%. The established method is rapid, reliable, and suitable for the ultrafast determination of six alkaloids in tobacco and tobacco products.


Assuntos
Alcaloides/análise , Nicotiana/química , Produtos do Tabaco/análise , Espectrometria de Massas , Fatores de Tempo
3.
J Pharm Biomed Anal ; 182: 113127, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32058184

RESUMO

In order to identify real and fake Panax notoginseng samples, the high performance liquid chromatography (HPLC) was used to analyze P. notoginseng samples of non-volatile characteristic components in P. notoginseng powder samples with 10 %, 30 %, 50 % ratio, combined with principal component analysis - mahalanobis distance (PCA-MD). The results showed that: (1) The PCA analysis showed that mahalanobis with different stem and leaf powder were divided into four categories, and the gravity center of the pattern (classification) showed that the long axis of the trend chart gradually increased with the increase of the proportion of the stem and leaf powder, and the trend chart was gradually away from the control group; (2) The mahalanobis distance indicated that the range of mahalanobis distance fluctuation (upper limit) of several P. notoginseng powder samples is 395.03∼48252.70. The larger the percentage of the stem and leaf powder in P. notoginseng samples, it is farther away from the normal P. notoginseng samples. It indicated that the product of P. notoginseng samples can be evaluated with the mahalanobis distance. The results of this study can be applied to identification and homogenization evaluation of P. notoginseng between real and fake samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Panax notoginseng/química , Pós/química , Folhas de Planta , Caules de Planta , Pós/análise , Análise de Componente Principal
4.
R Soc Open Sci ; 5(6): 172003, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30110467

RESUMO

To study puff-by-puff release characteristics of crotonaldehyde in mainstream cigarette smoke under diverse intensive smoking regimens, we designed an RM20H smoking machine with a puff-by-puff smoke collection unit to automatically trap crotonaldehyde in the mainstream cigarette smoke. Using this process, we trapped, puff-by-puff, crotonaldehyde in mainstream smoke generated by different smoking regimens and quantitatively analysed the levels of crotonaldehyde using high-performance liquid chromatography with a modified QuEChERS sample pretreatment method. On the basis of the crotonaldehyde in each puff, we determined crotonaldehyde's puff-by-puff release characteristics. The results showed that crotonaldehyde's puff-by-puff release remained nearly constant for the International Organization for Standardization mode while increased polynomial trend was seen (n ≥ 6) under the Massachusetts and Health Canada smoking regimens. The equation fit for various regimens was good (R2 > 0.9192). Release characteristics by puff were classified into four categories: (1) first, second and third puffs; (2) fourth and fifth puffs; (3) sixth puff; and (4) seventh and eighth puffs.

5.
J Asian Nat Prod Res ; 18(8): 779-83, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26982907

RESUMO

A new benzofuran derivative, methyl 3-acetyl-7-hydroxy-6-methoxy-2-methylbenzofuran-4-carboxylate (1), and a known compound pyrrolezanthine (2), were isolated from leaves of Nicotiana tabacum. Compound 1 was elucidated by means of spectroscopic methods, as well as X-ray diffraction. Both compounds 1 and 2 exhibited moderate inhibitory activities on human cancer cell lines.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Benzofuranos/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Nicotiana/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Benzofuranos/química , Benzofuranos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Pirróis/química , Pirróis/isolamento & purificação , Pirróis/farmacologia
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