不同方法提取侧柏叶中挥发性成分的气相色谱-质谱分析

采用气相色谱-质谱法(GC/MS)分析酶提取法(CE)、同时蒸馏萃取法(SDE)和水蒸气蒸馏-萃取法(DSE)三种方法提取侧柏叶挥发性成分。结果表明:三种方法提取侧柏叶挥发油的化学成分均有差异。酶提取法提取侧柏叶挥发油鉴定出32种化合物，主要成分为雪松烯，占挥发油总量的41.25%；同时蒸馏-萃取法提取侧柏叶挥发油鉴定出29种化合物，主要成分为雪松醇，占挥发油总量的39.06%；水蒸气蒸馏 萃取法提取侧柏叶挥发油鉴定出32种化合物，主要成分为雪松醇，占挥发油总量的31.43%。     

罗布麻叶挥发油的气相色谱-质谱分析

用挥发油提取器提取了罗布麻叶中挥发油,测得含量为w=0.02%。并采用气相色谱-质谱联用技术对罗布麻的挥发性成分进行了分离鉴定。分离出52种成分,共确认了其中25种成分,占挥发油总含量的85.38%。采用峰面积归一化法确定了各成分的相对含量,其中主要成分为氧化石竹烯(10.57%)、1-α-萜品醇(10.38%),苯甲酸-3-己烯酯(6.45%)、3,7,11,15-四甲基-2-十六碳烯-1-醇(5.99%)、大马酮(5.85%)、反式-金合欢醇(5.27%)、2-甲基-5-异丙基苯酚(4.77%)、长叶薄荷酮(4.25%)。     

新疆紫花苜蓿挥发油化学成分的分析

采用水蒸气蒸馏法提取新疆紫花苜蓿中的挥发油,通过气相色谱-质谱联用技术,结合计算机质谱图库检索,对分离的化合物进行结构分析。从紫花苜蓿挥发油中初步确定了53种化合物,占挥发性物质含量的95.6%,并用峰面积归一化法得出各化学成分在挥发油中的含量。紫花苜蓿挥发油主要组分为6,10,14-三甲基-2-十五酮（10.28%）、叶绿醇（8.23%）、反-2-烯基-己醛(5.46%)、3-甲基丁醛(3.61%)和沉香醇（3.17%）等。     

新疆阿魏挥发油成分气相色谱-质

采用水蒸气蒸馏法从新疆阿魏中提取挥发油成分,测得新疆阿魏挥发油的含量为1.0%。用气相色谱-质谱法(GC/MS)对新疆阿魏的挥发性成分进行了分离鉴定,分离出38种成分,共确认了其中36种成分,占检出量的92.32%。采用峰面积归一化法确定了各成分的相对含量,其中主要成分为2,3-二甲基-3-己醇(18.34%)、2-乙硫基-丁烷(8.00%)、丙基丁基二硫醚(6.95%)、十八烷基三烯(6.64%)、乙酸乙酯(6.21%)、油酸(5.10%)。     

水红花子挥发油的提取及GC/MS分析

采用正交试验法对水蒸气蒸馏提取水红花子挥发油的提取条件进行研究,用气相色谱-质谱联用技术测定最佳提取条件所得水红花子挥发油的化学成分,结果显示最佳提取条件为水红花子粉末（20目）加入800 mL水浸泡4 h,水蒸气蒸馏8 h。鉴定出其中24种成分, 含量最多是萜烯类化合物（27.36%）和酮类化合物(20.07%),其中主要为异长叶烯（19.45%）、α-石竹萜烯(0.84%)、α-蒎烯（0.99%）、石竹烯氧化物(3.20%)和香叶基丙酮(5.04%)。     

微波-萃取木香挥发性化学成分的气相色谱-质谱分析

采用微波照射 -萃取法提取木香挥发性物质 ,测得木香挥发油的含量为 4.5 % ,利用气相色谱 -质谱( GC/ MS)法分离确认出 48种化学成分 ,占总挥发油的 93 .3 %以上。用峰面积归一化法通过化学工作站数据处理系统得出各化学成分在挥发油中的相对百分含量。方法稳定可靠 ,重现性好 ,适用于中药挥发油的化学成分分析。     

两种方法提取芦荟花中挥发性化学成分的气相色谱-质谱分析

用蒸馏 -萃取法和同时蒸馏 -萃取法提取库拉索芦荟花的挥发性物质 ,测得用两种方法提取的芦荟花挥发油含量分别为 0 .85 %和 2 .81 %。用气相色谱 -质谱 ( GC/MS)法从芦荟花挥发油中分别分离并确定出 1 9种和 1 1种化学成分 ,分别占芦荟花挥发油总检出量的 99.1 4%和 96.70 %。用峰面积归一化法通过化学工作站数据处理系统 ,得出各化学成分在挥发油中的相对百分含量。     

虎杖饮片挥发油的提取及GC/MS分析

采用正交试验法对水蒸气蒸馏提取虎杖饮片挥发油的条件进行研究。结果表明最佳提取条件为虎杖粗粉（2~3 mm）加入7倍的水浸泡4 h，水蒸气蒸馏12 h。用气相色谱-质谱联用技术测定最佳提取条件所得虎杖饮片挥发油的化学成分，鉴定出其中20种成分,主要是噻吩类(38.09 %)、菲类(4.78 %)、芴类(3.81 %)、联苯类(3.47 %)、蒽类(2.92 %)和萘类(2.27 %)化合物。     

不同方法提取荜茇挥发油的GC/MS分析

采用气相色谱-质谱联用技术(GC/MS)对水蒸气蒸馏法(SD)和超临界CO2萃取法(SFE-CO2)所提取的荜茇挥发油化学成分及其含量进行分析。两种方法所提取的挥发油在外观,得率,化学成分及含量等方面均存在一定差异。用SFE-CO2法提取的挥发油得率高、提取时间短,是荜茇挥发油提取的理想方法。     

没药中挥发性成分的酶提取及GC/M

采用纤维素酶提取法(CE)和水蒸气蒸馏提取法(DSE)对没药挥发油成分进行比较研究。利用气相色谱-质谱联用技术对其化学成分进行分析,从中分别鉴定出34种和38种化学成分,用峰面积归一法通过数据处理系统得出各化学成分在挥发油中的百分含量,分别占挥发油总成分的70.05%和67.95%,共同组分中含量最多的是乙酸辛酯和辛醇。     

拳卷地钱不同提取部位的气相色谱-质谱分析比较和部分生物活性研究

基于拳卷地钱不同部位生物活性的不同 ,建立了采用气相色谱 -质谱 (GC/ MS)技术分析拳卷地钱不同提取部位的方法。拳卷地钱乙醇粗提物依次用石油醚和乙酸乙酯萃取 ,以 GC/ MS确定两部位挥发性成分的差异 ,并进行体外抗肝癌细胞试验。从石油醚部位共分离出 5 4个峰 ,鉴定了其中 2 5种物质 ,占总出峰面积的65 .0 %以上 ,在所分离的化合物中 ,以有机酸和酯类化合物为主 ;从乙酸乙酯部位分离出 2 3个峰 ,鉴定了其中 1 9种物质 ,占总出峰面积的 89.0 %以上 ,在所分离的化合物中 ,以苯并噻唑 (1 4.97% )和雪松醇 (2 0 .69% )为主。体外抗肝癌细胞试验 ,发现乙酸乙酯部位有明显抑制肝癌细胞的作用 ,并有剂量依赖关系 ;当质量浓度达 40 mg/ L时 ,对肝癌细胞有明显抑制作用。石油醚部位对肝癌细胞抑制作用不明显。     

Isolation and molecular identification of cellulolytic bacteria from Dig Rostam hot spring and study of their cellulase activity

Cellulose is the main structural component of lignocellulosic wastes that can be converted to sugars and biofuels by cellulase. Due to wide applications of this enzyme in various industries around the world, cellulase is considered as the third industrial enzyme. The ability of thermophilic bacteria in the production of heat-stable cellulases has made them valuable tools in biotechnology. The aim of this study was isolation and molecular identification of cellulolytic thermophile bacteria from Dig Rostam hot spring and investigating their cellulase activity. Samples were taken from water and sediments of this hot spring, and cellulolytic bacteria were enriched in media containing cellulose as the only carbon source. The bacteria were incubated at 60°C, and single colonies were then isolated on solid media. Congo red assay was used as a quick test for the qualitative screening of cellulase activity. According to these qualitative results, four colonies named CDB1, CDB2, CDB3, and CDB4 were isolated, and their growth curve and some other characteristics were determined by biochemical assays. Moreover, endoglucanase, exoglucanase, and FPase activities of the isolates were investigated quantitatively. Results indicated that CDB1 exhibited the highest endoglucanase (0.096 U/mL) and exoglucanase (0.156 U/mL) activities among other isolates. 16S rDNA partial sequencing indicated that CDB1 had 99% similarity to the genus Anoxybacillus, and the other isolates showed the highest similarity to the genus Geobacillus. The cellulase gene of CDB1 isolate with the highest cellulase activity was also cloned, and its sequence is reported for the first time. Further studies on this thermophilic enzyme might be useful for industrial applications.     

ANALYSIS OF CAPSAICIN AND DIHYDROCAPSAICIN IN HOT PEPPERS BY ULTRASOUND ASSISTED EXTRACTION FOLLOWED BY GAS CHROMATOGRAPHY–MASS SPECTROMETRY

A simple method for the analysis of capsaicin and dihydrocapsaicin in peppers by ultrasound assisted extraction (USAE) followed by gas chromatography–mass spectrometry (GC-MS) has been developed. USAE conditions were optimized by experimental design in order to maximize analyte extraction. A full factorial design involving extraction variables such as solvent (ethanol and water), extraction time (5–25 min), extraction temperature (25–50 °C), sample amount (0.25–0.5 g), and ultrasound amplitude (40–80%) was applied. The most significant conditions for capsaicinoid extraction by USAE were solvent type, extraction time, and sample amount. The obtained results were compared with other extraction methods: the official Soxhlet method and a previously reported solid phase microextraction method. Results showed that the extraction efficiency with the application of USAE (98%) was as good as that obtained with Soxhlet and the precision of recovery was less than 5%; in addition, the extraction time was decreased from 5 h to 25 min. The GC-MS analytical method was linear in the range 10–100 μg/mL for capsaicin and dihydrocpsaicin with correlation coefficient r = 0.998 and peak area variability of ～1% for both capsaicinoids. The method was applied to the analysis of 11 varieties of hot peppers cultivated in México. A large concentration range for capsaicin (101–6800 μg/g) and dihydrocapsaicin (110–2736 μg/g) was found in these pepper samples.     

香叶中挥发性组分的超临界萃取及气相色谱-质谱分析

用正交试验法研究超临界萃取香叶挥发性成分的条件，并用气相色谱-质谱联用技术分析了香叶挥发油的化学成分。结果显示萃取条件按对结果影响大小依次排列为：萃取压力、萃取温度、萃取时间,最佳萃取条件为萃取压力30 MPa、萃取温度40 ℃、萃取时间1 h。挥发油收率为2.6%,从中确认出47种化学成分，而用同时水蒸气蒸馏 溶剂萃取方法收率仅为0.8%，仅确认出30种挥发性成分。     

Enzyme-gold affinity labelling of cellulose

The enzyme-linked colloidal gold affinity labelling technique was tested as a method to localize cellulose on thin sections of plant cell walls and slime mold spores. Commercially available cellulase from cultures of Trichoderma reesei, the main components being cellobiohydrolase I and II (CBH I, CBH II) and endoglucanase (EG), was linked to colloidal gold by using standard techniques and applied as a dilute, buffered suspension to thin sections. After brief exposure, e.g., 15–30 minutes, cellulose exposed on the surface of sections was labelled with the enzyme-gold complex. Poststaining did not appear to have a deleterious effect on the labelled sections. The specificity of labelling was demonstrated by its complete inhibition when carboxymethylcellulose was incorporated in the labelling mixture, by lack of labelling of 1,4-β-mannans or 1,3-β-xylans in noncellulosic walls of marine algae, by lack of labelling of 1,4-β-glucans in chitin, by much lower labelling density when done at 4°C, and by lack of labelling when sections were predigested with cellulase. Labelling with the crude commercial cellulase was compared to labelling with purified CBH I-, CBH II-, and EG-linked colloidal gold, and the labelling pattern was similar. This method was found useful on conventionally fixed material and required no special preparation other than the use of inert (Ni or Au) grids and 0.5% gelatin to reduce nonspecific binding of the gold complex. Labelling was similar in the several embedding resins tested: LR White, Lowicryl K4M, Epon 812, and Spurr's. The cellulase-gold probe remained active for at least 4 weeks at 4°C and much longer when frozen at ?80°C in 20% glycerol. This technique should prove useful in studies of cellulose degradation and cellulose deposition and of the interaction of cellulose with other wall components.     

PVC木塑家具中邻苯二甲酸酯增塑剂检测方法研究

比较研究了超声萃取法和传统索氏提取法测定聚氯乙烯(PVC)木塑家具中6种邻苯二甲酸酯增塑剂(PAEs)的分析方法。通过正交试验研究提取溶剂、样品质量和提取时间3个因素的显著性,并优化了参数。在优化条件下,索氏提取法和超声萃取法的平均回收率均大于80%,精密度均小于10%。以邻苯二甲酸二丁酯(DBP)和邻苯二甲酸二异壬酯(DINP)为例,通过F检验和T检验显著性统计,两种处理方法的精密度和准确度不存在差异。相对于传统的索氏提取法,超声萃取法具有操作简单、溶剂用量少和省时的有点,可以较好的应用于PVC木塑家具产品及相关木塑材料中6种PAEs增塑剂检测。     

加速溶剂萃取法结合HPLC-ESI-TOF MS测定清肝散结汤中29种化学成分

清肝散结汤（QGSJ）是由14味不同中药组成的复方制剂，基于长期的实验观察和临床经验以不同组合成方用于肝癌的治疗。本研究建立了一种基于加速溶剂萃取（ASE）结合高效液相色谱-电喷雾飞行时间质谱（HPLC-ESI-TOF MS）的方法同时测定清肝散结汤中29种化学成分。使用70%乙醇作为提取溶剂，提取温度100 ℃，静态萃取时间5 min，提取2次，以上条件采用正交设计和主成分分析进行优化。HPLC分离采用Kromasil C18色谱柱，梯度洗脱。TOF MS在负离子模式下检测，质量扫描范围m/z 100~1100。结果表明：清肝散结汤中29种成分具有良好的线性关系（r＞0.994）和日内、日间精密度（RSD＜5%）；提取回收率在96.5%~104.5%之间。该方法快速、可靠，适用于复方中药的定量评价。     

甲基化处理气相色谱-质谱法同时检测大米中12种酸性除草剂

实验采用丙酮酸性水溶液(150∶20,体积比)提取试样中农药残留物,提取液用乙酸乙酯液液分配、凝胶渗透色谱仪(GPC)净化后,用重氮甲烷乙醚溶液衍生化,用气相色谱-质谱(GC/MS)选择离子监测模式(SIM)内标法(IS)测定,分离色谱柱为DB-5MS。10种农药的回收率≥80%;相对标准偏差≤10%;最低检测限0.01~0.05 mg/kg。