白芷酒炖前后挥发性成分的HS-SPME-GC-MS分析

目的探讨白芷酒炖前后对挥发性成分的影响。方法采用顶空固相微萃取技术(HS-SPME)结合气相色谱-质谱法(GC-MS)对白芷酒炖前后挥发性成分及其相对百分含量进行对比分析。结果从白芷生品中初步检测出53个峰,鉴定出36个成分;从白芷酒炖中检测出32个峰,鉴定出26个成分;与生品成分比较,酒炖白芷中有22种成分未测到,但新增了12种成分,表明酒炖白芷中的挥发性成分的组成和含量均发生了变化。结论白芷酒炖后由于受热及辅料黄酒的作用使挥发性成分的种类及含量发生了明显变化,并存在成分转化,本研究为白芷酒炖的炮制机理及其在都梁丸中应用的物质基础研究提供了科学依据。     

Non-destructive profiling of volatile organic compounds using HS-SPME/GC–MS and its application for the geographical discrimination of white rice

The authenticity determination of white rice is crucial to prevent deceptive origin labeling and dishonest trading. However, a non-destructive and comprehensive method for rapidly discriminating the geographical origins of white rice between countries is still lacking. In the current study, we developed a volatile organic compound based geographical discrimination method using headspace solid-phase microextraction coupled to gas chromatography–mass spectrometry (HS-SPME/GC–MS) to discriminate rice samples from Korea and China. A partial least squares discriminant analysis (PLS-DA) model exhibited a good classification of white rice between Korea and China (accuracy = 0.958, goodness of fit = 0.937, goodness of prediction = 0.831, and permutation test p-value = 0.043). Combining the PLS-DA based feature selection with the differentially expressed features from the unpaired t-test and significance analysis of microarrays, 12 discriminatory biomarkers were found. Among them, hexanal and 1-hexanol have been previously known to be associated with the cultivation environment and storage conditions. Other hydrocarbon biomarkers are novel, and their impact on rice production and storage remains to be elucidated. In conclusion, our findings highlight the ability to rapidly discriminate white rice from Korea and China. The developed method maybe useful for the authenticity and quality control of white rice.     

Quality control tests for the crude drug of Conyza filaginoides

Context. Conyza filaginoides (D.C.) Hieron (Asteraceae) is a medicinal Mexican plant highly prized in contemporary Mexico for the treatment of upset stomach and diabetes.

Objective: This work was undertaken to develop a suitable high performance liquid chromatography (HPLC)-diode array detection (DAD) method for quantifying rutin (1), the main active principle from the aerial parts of C. filaginoides.

Materials and methods: The method was performed using a LiChrospher 100 RP-18 column. The mobile phase was water (containing 0.1% phosphoric acid)-methanol-acetonitrile (80:5:15, v/v) at a flow rate of 1.2?mL?min^?1.

Results: Limits of detection and quantification were 7.5 and 22.8?μg?mL^?1, respectively. The main recoveries measured at three concentrations were higher than 98%, with RSD <2%. Quantitative analysis of a few samples showed the presence of high concentrations of 1 (3.6?±?0.2?g/100?g of dry plant material). The volatile components were extracted by hydrodistillation or head space solid-phase microextraction (HS-SPME), and thereafter analyzed by gas chromatography coupled to mass spectrometry (GC-MS). Forty-three chemical constituents representing 90% of the total content of the oil were identified. The major light volatile compounds obtained by HS-SPME revealed a high content of monoterpene hydrocarbons.

Conclusions: A precise, reliable, and accurate analytical HPLC method to detect and quantify 1 in the crude drug and some preparations were developed and fully validated. The volatile components of the plant are described for the first time. The proposed method would be useful for quality control assurance of this important Mexican plant.     

顶空固相微萃取-气相色谱-质谱联用法分析松花粉挥发性成分

采用顶空固相微萃取-气相色谱-质谱联用法(HS-SPME-GC-MS)分离,鉴定了松花粉中的挥发性成分。实验中筛选了固相微萃取纤维,优化了SPME的操作条件。样品在70℃下,用100μm聚丙烯酸酯(PA)固相微萃取纤维对松花粉样品顶空吸附30 min,于250℃脱附10 min然后采用GC-MS对解析物进行分离鉴定。采用HS-SPME-GC-MS测得85个峰,鉴定出70种组分,主要为脂肪类化合物。结果表明:HS-SPME可用于松花粉中挥发性成分的快速分析。     

Dose-concentration relationships of methadone and EDDP in hair of patients on a methadone-maintenance program

After controlled oral administration of d,l-methadone solution (15–260 mg/day) in the context of a methadone-maintenance program, concentrations of methadone and 2-ethylidine-1,5-dimethyl-3,3-diphenyl-l-pyrrolidine (EDDP), in head hair were determined (N=41), using a fully automated headspace solid-phase microextraction procedure in combination with gas chromatography and mass spectrometry (HS-SPME/GC/MS). Methadone was present in all samples in concentrations ranging from 0.25 to 13.29 ng/mg (mean 2.69±0.45 ng/mg). EDDP was also present in every sample in concentrations ranging from 0.05 to 2.17 ng/mg (mean 0.43±0.08). The concentration ratio methadone/EDDP was 7.5±5.7 in the proximal segments, but decreased to 4.8±1.4 in the distal segments. A statistically significant correlation between the intake dose and the methadone and EDDP concentrations in the subjects’ hair could be established only in the proximal segments (r=0.913 for methadone and r=0.901 for EDDP), but not in the distal segments. In all, 131 segments analyzed, the correlation coefficient was r=0.760 for methadone and r=0.738 for EDDP. In comparison to the dose-concentration relationship reported in the literature, we found a better correlation with higher correlation coefficients especially in the proximal segments. However, owing to a broad distribution in the correlation between dosage and concentration, the determination of methadone and EDDP in hair holds only limited information about prior methadone administration.     

Non-destructive profiling of volatile organic compounds using HS-SPME/GC–MS and its application for the geographical discrimination of white rice

The authenticity determination of white rice is crucial to prevent deceptive origin labeling and dishonest trading. However, a non-destructive and comprehensive method for rapidly discriminating the geographical origins of white rice between countries is still lacking. In the current study, we developed a volatile organic compound based geographical discrimination method using headspace solid-phase microextraction coupled to gas chromatography–mass spectrometry (HS-SPME/GC–MS) to discriminate rice samples from Korea and China. A partial least squares discriminant analysis (PLS-DA) model exhibited a good classification of white rice between Korea and China (accuracy = 0.958, goodness of fit = 0.937, goodness of prediction = 0.831, and permutation test p-value = 0.043). Combining the PLS-DA based feature selection with the differentially expressed features from the unpaired t-test and significance analysis of microarrays, 12 discriminatory biomarkers were found. Among them, hexanal and 1-hexanol have been previously known to be associated with the cultivation environment and storage conditions. Other hydrocarbon biomarkers are novel, and their impact on rice production and storage remains to be elucidated. In conclusion, our findings highlight the ability to rapidly discriminate white rice from Korea and China. The developed method maybe useful for the authenticity and quality control of white rice.     

Protective Effects Induced by a Hydroalcoholic Allium sativum Extract in Isolated Mouse Heart

The aim of the present study was to investigate the possible protective effects of a garlic hydroalcoholic extract on the burden of oxidative stress and inflammation occurring on mouse heart specimens exposed to E. coli lipopolysaccharide (LPS), which is a well-established inflammatory stimulus. Headspace solid-phase microextraction combined with the gas chromatography–mass spectrometry (HS-SPME/GC–MS) technique was applied to determine the volatile fraction of the garlic powder, and the HS-SPME conditions were optimized for each of the most representative classes of compounds. CIEL*a*b* colorimetric analyses were performed on the powder sample at the time of delivery, after four and after eight months of storage at room temperature in the dark, to evaluate the color changing. Freshly prepared hydroalcoholic extract was also evaluated in its color character. Furthermore, the hydroalcoholic extract was analyzed through GC–MS. The extract was found to be able to significantly inhibit LPS-induced prostaglandin (PG) E₂ and 8-iso-PGF_2α levels, as well as mRNA levels of cyclooxygenase (COX)-2, interleukin (IL)-6, and nuclear factor-kB (NF-kB), in heart specimens. Concluding, our findings showed that the garlic hydroalcoholic extract exhibited cardioprotective effects on multiple inflammatory and oxidative stress pathways.     

An evaluation of volatile compounds released from containers commonly used in circulation of sports beverages

In an effort to identify and quantify important volatile organic compounds (VOCs) released from sports beverage containers commonly used for storage and distribution, three brands of sports beverages with poly ethylene terephthalate (PET) and metal cans were analyzed through headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). Out of 80 volatile compounds identified from all container types, I-limonene recorded the highest concentration (34.3-118 pmol mol⁻¹) along with 12 other VOCs detected most frequently (more than 3 out of all 6 products) such as 2-methyl-6-methylene-2,7-octadiene, alpha-terpineol, decanaldehyde, and p-isopropyltoluene. When each container was filled up with water and analyzed after a long-term storage (49 days), a total of 14 VOCs were detected. According to our analysis, all the VOCs detected from either beverage or container materials were below the safety limits prescribed previously by diverse agencies. However, an extension of these analyses may be necessary for other beverage types, as certain VOCs can be migrated from container materials.     

安息香不同提取方法的GC-MS研究

目的:考察安息香不同提取方法的化学成分异同,探索安息香挥发性成分分析的最宜提取方法.方法:应用气相色谱-质谱联用技术,分析安息香溶剂提取部位(石油醚和乙醚提取)、水蒸气蒸馏提取挥发油、顶空固相微萃取挥发性成分的异同.结果:安息香溶剂提取鉴定出5个化合物(其中石油醚部位4个化合物、乙醚部位4个化合物),水蒸气蒸馏提取的挥发油鉴定出19个化合物,顶空固相微萃取鉴定出12个化合物.3种方法所得成分中皆含有苯甲酸、苯甲酸苄酯、香草醛、肉桂酸苄酯4种成分,3种方法中常规水蒸气蒸馏得到的成分相对较多种类较全面.结论:3种提取方法中,安息香经常规水蒸气蒸馏提取得到的成分最多且种类最全面,提示此3种提取方法中常规水蒸气蒸馏是安息香挥发性成分分析的最宜方法.     

SD-HS-SPME-GC-MS分析华中碎米荠挥发性成分

目的:对华中碎米荠挥发性成分进行研究。方法:分别采用水蒸气蒸馏法(SD)和顶空固相微萃取法(HS-SPME)提取华中碎米荠挥发性成分;通过气质联用(GC-MS)分析其化学成分组成,并应用色谱峰面积归一化法计算各成分的相对百分含量。结果:采用SD-GC-MS共分离出67个色谱峰,鉴别出其中34个化合物,占挥发油总量的94.34%;采用HS-SPME-GC-MS共分离出62个色谱峰,鉴别出其中48个化合物,占总挥发性成分的98.29%。通过这两种技术共同鉴定出的挥发性成分共有5种,其中含量最高的成分为4-异硫代氰酰基-1-丁烯。结论:SD与HS-SPME分别适用于不同类型的挥发性成分的提取,两者联用分析华中碎米荠挥发性成分能够得到更加全面的信息。