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1.
Foods ; 13(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38890863

RESUMO

The adsorption characteristics of ß-glucooligosaccharides on activated carbon and the purification were systematically investigated. The maximum adsorption capacity of activated carbon reached 0.419 g/g in the optimal conditions. The adsorption behavior was described to be monolayer, spontaneous, and exothermic based on several models' fitting results. Five fractions with different degrees of polymerization (DPs) and structures of ß-glucooligosaccharides were obtained by gradient ethanol elution. 10E mainly contained disaccharides with dp2a (G1→6G) and dp2b (G1→3G). 20E possessed trisaccharides with dp3a (G1→6G1→3G) and dp3b (G1→3G1→3G). 30E mainly consisted of dp3a and dp4a (G1→3G1→3(G1→6)G), dp4b (G1→6G1→3G1→3G), and dp4c (G1→3G1→3G1→3G). In addition to tetrasaccharides, 40E and 50E also contained pentasaccharides and hexasaccharides with ß-(1→3)-linked or ß-(1→6)-linked glucose residues. All fractions could inhibit the accumulation of intracellular reactive oxygen species (ROS) in H2O2-induced Caco-2 cells, and they could improve oxidative stress damage by increasing the activity of superoxide dismutase (SOD) and reduced glutathione (GSH), which were related to their DPs and structures. 50E with high DPs showed better anti-oxidative stress activity.

2.
Heliyon ; 9(1): e12146, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36685456

RESUMO

In order to investigate the difference of volatile substances among flavored cigarette paper, which are supplied by several manufacturers with different batches, the stability of the complex system of scented cigarette paper was analyzed and evaluated. In this study, Headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) was used to detect the aroma compounds of 23 flavored cigarette paper samples. Based on fingerprint analysis, the differences and changes of aroma compounds of different samples were studied in the form of data visualization. Principal component analysis, partial least squares regression analysis, cluster heatmap analysis and artificial neural network analysis were used to evaluate the stability of different cigarette paper. The results show that: A total of 29 volatile substances were identified from different scented cigarette paper. Fingerprint analysis revealed that the volatile substances of different cigarette paper samples were roughly the same, but not the content. The results of chemometrics analysis showed that there were significant differences in the characteristic aroma compounds of cigarette paper from different manufacturers. HS-GC-IMS technology combined with chemometrics method could be applied to determine the difference of volatile substances among different flavored cigarette paper, which theoretically and technically supported the quality stability maintenance and identification of flavored cigarette paper processed in different places.

3.
Front Microbiol ; 13: 1035434, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36312978

RESUMO

Ganoderma is a globally distributed genus that encompasses species with forestry ecological, medicinal, economic, and cultural importance. Despite the importance of this fungus, the studies on the species diversity of Ganoderma in Yunnan Province, China (YPC) have poorly been carried out. During this study, opportunistic sampling was used to collect 21 specimens of Ganoderma from YPC. Morphology and multigene phylogeny of the internal transcribed spacer (ITS) regions, the large subunit of nuclear ribosomal RNA gene (nrLSU), the translation elongation factor 1-α gene (TEF1-α), and the second largest subunit of RNA polymerase II (RPB2) were used to identify them. Morphological and molecular characterization of the 21 specimens showed that they belong to 18 species of Ganoderma, of which three are novel viz. G. artocarpicola, G. obscuratum and G. yunnanense. Ganoderma artocarpicola is characterized by the sessile and concrescent basidiomata, reddish brown to yellowish brown pileus surface, heterogeneous context, wavy margin, and ovoid basidiospores. Ganoderma obscuratum is distinguished by small pores (6-9 per mm), dorsolaterally sub-stipitate basidiomata which become greyish-brown when dry, and narrow ellipsoid basidiospores. Ganoderma yunnanense is characterized by cream color pore surface and context, centrally to laterally stipitate basidiomata with reddish-brown to violet-brown strongly laccate pileus surface, and broadly ellipsoid basidiospores. With the help of an extensive literature survey and the results of this study, a checklist of 32 Ganoderma species from YPC was established, which accounts for 71.11% of the known species in China. In addition, a key to the Ganoderma in YPC is also provided.

4.
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
5.
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
6.
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.

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