scholarly journals Retention indices, relative response factors, and mass spectra of trifluoroacetate esters of phenolic compounds determined by capillary GC/MS: Topical report

1989 ◽  
Author(s):  
Yu, S. K.-T. ◽  
R. P. Vrana ◽  
J. B. Green
Author(s):  
Наум Аронович Эпштейн

Представлены формулы для расчета коэффициентов относительной чувствительности RRF (relative response factors) и поправочных коэффициентов F (correction factors) примесей, а также формулы, необходимые для понимания сущности коэффициентов RRF и F. Рассмотрены основные способы определения поправочных коэффициентов и их ограничения (условия, выполнение которых необходимо для корректного определения RRF и F). Эти ограничения не отражены в Европейской фармакопее и в Фармакопее США, но от их учета зависит правильность определения значений поправочных коэффициентов. Приведены примеры и даны рекомендации для надежного определения и правильного использования поправочных коэффициентов.


2012 ◽  
Vol 7 (7) ◽  
pp. 1934578X1200700 ◽  
Author(s):  
Norma Hussin ◽  
Luigi Mondello ◽  
Rosaria Costa ◽  
Paola Dugo ◽  
Nik Idris Nik Yusoff ◽  
...  

Patchouli essential oil can be obtained from fresh, dried and fermented plant material. It is a highly valuable product in the fragrance industry and its quality changes depending upon raw material age and oil storage. In this work, patchouli essential oils derived from different treatments have been subjected to GC-FID quantitative analysis using an internal standard (ISTD) method with response factors (RF). Samples were obtained from i) fresh plants; ii) hydrodistillation of one year mature and fermented plants; iii) hydrodistillation of one year mature plants; iv) commercial products from Indonesia and Malaysia. Linear Retention Indices (LRI) for both polar and non-polar GC-MS analyses were also measured as a tool for qualitative analysis towards a homologous series of C7-C30 n-alkanes. The results obtained confirmed that, in all samples, patchouli alcohol was the main volatile constituent, with higher amount in lab-scale produced oils, compared with commercial samples. Other major compounds, in lab oils and commercial samples respectively, were: δ-guaiene, α-guaiene, pogostol, seychellene and α-patchoulene. Another 36 compounds were also found.


1993 ◽  
Vol 48 (9-10) ◽  
pp. 736-744 ◽  
Author(s):  
Ralf Engel ◽  
Paul-Gerhard Gülz ◽  
Thorsten Herrmann ◽  
Adolf Nahrstedt

Glandular trichomes in form of long stretched tubes are present on the lower leaf side of Quercus robur as shown by scanning electron microscopy. The glands contain an essential oil, which was isolated by steam distillation together with volatile waxy components of the leaves in an amount of 0.025% of fresh leaves. The product of steam distillation was analyzed by GC-MS. Identification of com pounds is based on comparison of their mass spectral data with those of authentic samples in combination with retention indices and MS data using the SeKoMS (Search Kovats Indices and Mass Spectra) Library. Altogether 184 components of the product of steam distillation were separated, 155 of which could be identified, another 7 were tentatively assigned. Three groups of substances according to their chemical composition are found: hexenyl derivatives and some acetals (32%); terpenes including monoterpenes (4% ), sesquiterpenes and diterpenes (21%); and alkane derivatives (35%). The residual 8% consist of benzyl alcohol, com pounds which stem from the degradation of carotenes, and miscellaneous constituents


2015 ◽  
Vol 10 (7) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Isabelle A. Kagan ◽  
Ben M. Goff ◽  
Michael D. Flythe

Red clover ( Trifolium pratense) contains soluble phenolic compounds with roles in inhibiting proteolysis and ammonia production. Alfalfa ( Medicago sativa) has been found to have a low phenolic content, but few alfalfa and red clover cultivars have been compared for phenolic content. Total soluble phenolics were quantified by a Folin-Ciocalteu colorimetric assay in nine red clover and 27 alfalfa cultivars. Mean total phenolic contents of red clover and alfalfa were 36.5 ± 4.3 mg/gdw and 15.8 ± 1.4 mg/gdw, respectively, with the greater standard deviation of red clover possibly indicating more diversity in phenolic content. Because different phenolic standards had different response factors in the colorimetric assay, the red clover and 11 alfalfa cultivars were analyzed by HPLC to determine if the differences in total soluble phenolics between genera reflected differences in the amounts of phenolics or in the classes of phenolics responding to the colorimetric assay. Two red clover cultivars differed in total phenolics and phaselic acid. Alfalfa produced different phenolic compounds from red clover, at lower concentrations. Extracts of two red clover cultivars were separated by thin-layer chromatography (TLC), and the bands were assayed for activity against Clostridium sticklandii, a bovine ruminal hyper ammonia-producing bacterium (HAB). Only biochanin A had anti-HAB activity. Inhibitory amounts indicated that five red clover cultivars could be suitable sources of anti-HAB activity.


2009 ◽  
Vol 4 (1) ◽  
pp. 1934578X0900400 ◽  
Author(s):  
Shio Murakami ◽  
Mariko Matsuura ◽  
Tadaaki Satou ◽  
Shinichiro Hayashi ◽  
Kazuo Koike

In phytotherapy, the essential oil from the leaves of Alpinia zerumbet ( Alpinia speciosa K. Schum.) (EOAZ) is used for neuropsychiatric symptoms, such as depression, stress and anxiety, and chronic problems that are associated with reproductive hormone imbalances in women. The chemical composition of EOAZ was analyzed by GC/MS, and the EOAZ properties inducing behavioral alterations in mice were examined by behavioral observations (BO) and an elevated plus-maze task (EPM), widely used as a method for assessing anxiolytic-like behaviors. Five major compounds, p-cymene (28.0 ± 5.0%), 1,8-cineole (17.9 ± 4.2%), terpinen-4-ol (11.9 ± 6.3%), limonene (6.3 ± 2.2%), and camphor (5.2 ± 2.1%) were identified by retention indices, mass spectra and comparison with standards. Inhalational administration of EOAZ (8.7 ppm) induced unique jumping behaviors in mice. To further investigate the behavioral regulatory mechanisms of EOAZ, we administered an intraperitoneal injection of either 10 mg/kg 5-HTP or 10 mg/kg fluoxetine prior to the EOAZ inhalations. By 5-HTP or fluoxetine pretreatments, the jumping frequencies were significantly decreased. In EPM, EOAZ (0.087 and 8.7 ppm) obviously showed the anxiolytic-like activity in mice.


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