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201.
Tobacco flavors increase the attractiveness of a tobacco brand and ultimately promote addiction. Information about what flavor and how much flavor is in flavor capsules can provide an effective way to regulate tobacco flavor. In this study, 128 flavor chemicals were identified and quantified by gas chromatography–mass spectrometry using libraries and authentic standards. Validation of the developed method was performed for interference, detection limits, calibration curves, accuracy, and precision. Menthol was the main ingredient in all capsules, and the carcinogenic pulegone was detected. Detected menthofuran, benzyl alcohol, geraniol, and eugenol cause toxic or severe irritation, and detected lactones can increase nicotine addiction by inhibiting nicotine metabolism in smokers. Margin of exposures for carcinogenic pulegone and non-carcinogenic menthol were well below safety thresholds, indicating a significant risk of inhalation exposure. It is desirable to prohibit the use of flavor capsules in consideration of human risk. 相似文献
202.
Gabrielle Fernanda Zimmer Roberta Oliveira Santos Iberê Damé Teixeira Rosana de Cassia de Souza Schneider Gilson Augusto Helfer Adilson Ben da Costa 《Journal of Chemometrics》2020,34(12):e3303
This study aims to develop, evaluate, and optimize the application of near-infrared spectroscopy (NIR) autosampler device equipped with a fiber-optic probe associated with chemometric methods for the fast quantification of routine chemical constituents such as total alkaloids, reducing sugars, nitrate, and ammonia in tobacco. For this purpose, an NIR autosampler device with capacity for 40 samples was used. The spectra were collected in the range of 950 to 2,500 nm, with three spins on the sample, a 3.0-cm2 sample scanning area, and 2.0 ± 0.2 mm distance between the fiber-optic probe and the sample. Four partial least-squares (PLS) models were developed, and different preprocessing methods were investigated. The predicted results were compared with those obtained from the reference method (continuous-flow analysis), and root mean square error of prediction values of 0.31%, 1.27%, 0.47%, and 0.026% were obtained for total alkaloids, reducing sugars, nitrate, and ammonia, respectively. The proposed method performed well for the analysis of total alkaloids and reducing sugars with an appropriate goodness-of-fit and fair precision. In conclusion, considering the performance of the regression models and the associated environmental and economic advantages, the application of NIR spectrometer autosampler device equipped with a fiber-optic probe associated with a PLS and synergy interval PLS algorithms cannot replace the reference method, but it is a promising tool for tobacco monitoring. 相似文献
203.
Marija Banoi&#x; Ines Banjari Ivana Flanjak Mate Pa&#x;tar Jelena Vladi&#x; Stela Joki&#x; 《Molecules (Basel, Switzerland)》2021,26(14)
This study intends to valorize by-products of the industrial processing of tobacco to obtain nicotine and phenolics as value-added compounds. Three influential parameters of the microwave-assisted extraction-MAE (temperature, treatment time, and solvent/solid ratio) were studied for the optimization of the extraction protocol for tobacco leaves and three types of waste—scrap, dust, and midrib, respectively. Nicotine was the dominant bioactive compound in all extracts, ranging from 1.512 to 5.480% in leaves, 1.886 to 3.709% in scrap, 2.628 to 4.840% dust, and 0.867 to 1.783% in midrib extracts. Five phenolic compounds were identified and quantified, predominated by chlorogenic acid and rutin. Additionally, total phenol content and antioxidant activity were determined using spectrophotometric assays. Optimization was performed in two aspects: to obtain a maximum extraction yield with minimum nicotine content and to obtain a maximum extraction yield with maximum nicotine content. These findings demonstrate that tobacco waste is a valuable source of bioactive compounds and MAE can be a promising alternative technique to obtain extracts rich in targeted bioactive compounds, especially nicotine. 相似文献
204.
Danqing Xie Lei Yao Yan Huang Shuaifan Wu Li Ma Yuhong Li Wencui Wang 《Molecules (Basel, Switzerland)》2021,26(14)
Tobacco (Nicotiana tabacum Linn.) is a famous traditional herb used in folk medicine. The essential oils of tobacco have been demonstrated in modern studies to possess antioxidant, anti-inflammatory, and neuroprotective properties, while its anxiolytic effect has not been reported. The purpose of this study was to evaluate the anxiolytic effect of Yunnan tobacco essential oil (YTO) and Zimbabwe tobacco essential oil (ZTO) on mice. The constituents of YTO and ZTO were analyzed by GC/MS. The anxiolytic effect of YTO and ZTO (0.1%, 1%, and 10%, v/v) on male ICR mice was evaluated in the light–dark box test (LDB) and the elevated plus maze test (EPM) test via inhalation and transdermal administration. After the behavioral tests, salivary corticosterone levels in mice were measured. The behavioral analysis showed that the administration of both YTO and ZTO elevated the time that the mice spent in the light chamber in the LDB test compared to the untreated control. In the EPM test, YTO and ZTO increased the time spent in open arms and the number of entries into the open arms. In addition, both YTO and ZTO significantly decreased salivary corticosterone levels in mice (p ≤ 0.001). In summary, our results demonstrated that inhalation and transdermal administration of both YTO and ZTO showed anxiolytic effect on male ICR mice. 相似文献
205.
Tobacco is widely used as a model plant for feasibility studies of recombinant protein production from transgenic plants. However, dealing with large quantities of biomass to recover recombinant proteins is a challenge for down-stream processing. In this study, the effect of isoelectric precipitation on native tobacco protein was first studied. Among the three acids studied, hydrochloric acid is shown to be more effective than acetic or citric acid, and at pH 4, 60% of native tobacco protein was precipitated by HCl. Egg white lysozyme was used as the model protein to test the feasibility of polyelectrolyte precipitation in protein recovery from tobacco extract. Precipitation of lysozyme at pH 7 was shown ineffective probably because of the interference of polyphenolic acids. However, after isoelectric precipitation at pH 5 poly(acrylic) acid (PAA) was shown to precipitate 85% of the soluble lysozyme when the polymer dosage was increased to 1.5 mg polymer/mg lysozyme, while negligible amounts of native tobacco protein was co-precipitated. Lysozyme precipitation by PAA in tobacco extract obtained at pH 5 was also studied, and lysozyme yield was significant improved. 相似文献
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209.
再造烟叶如今已成为现代卷烟配方设计的一种重要原材料,但是造纸法再造烟叶生产中会产生大量高色度的废水,如何经济快速合理地处理再造烟叶的生产废水,解决再造烟叶生产带来的环境污染问题,已成为一个亟须解决的社会问题。以再造烟叶生产废水为主要研究对象,从不同来源的污泥样品中筛选出56株菌株,从生理生化性质方面对其中降解能力较强的10株进行初步鉴定。同时,研究了复合菌群对废水的综合脱色效果,发现在温度37℃、pH 6.0、接种量20%的条件下脱色效果最好,在最优条件下进行混合菌群脱色,14 h脱色率可达76.6%。 相似文献
210.