Gas Chromatographic/Mass Spectrometric Analysis of the Essential Oil of Houttuynia cordata Thunb by Using On-Column Methylation with Tetramethylammonium Acetate

Abstract This paper describes a simple and novel on-column derivatization procedure used with gas chromatography/mass spectrometry (GC/MS) for the analysis of essential oil of Houttuynia cordata Thunb (HCT), a traditional Chinese medicine. In the procedure, the essential oil was obtained by hydrodistillation, and the fatty acid components were derivatized with tetramethylammonium acetate (TMAA) at 250°C and identified by GC/MS. Methylation improved the determination of both the fatty acids and the other components in the essential oil of HCT. To obtain optimum methylation conditions, several important factors were investigated with pentadecane as the internal standard and a GC inlet temperature of 250°C. Tetramethylammonium hydroxide (TMAH) and TMAA were compared as the derivatization agent, and a 2:1 ratio of TMAA to capric acid was evaluated. Fatty acid methyl esters produced good chromatographic peak shapes and did not interfere with the determination of dodecanal and caryophyllene. TMAA is a neutral methylation reagent, and it yielded no side reactions during derivatization. It was found that the fatty acid content of the essential oil was about 81%; among the methylated fatty acids found were capric acid, methyl (43.66%), methyl laurate (16.15%), methyl hexadecanoate (9.27%), undecanoic acid, methyl (5.62%), methyl oleate (1.98%), and methyl linoleate (1.40%). Other major constituents were (-)-β-pinene (1.02%), β-myrcene (1.62%), 1-terpinen-4-ol (1.59%), decanal (1.49%), and 2-undecanone (1.47%). The results obtained demonstrated good efficiency for the procedure. Pure chromatograms allowed quantitation, which was obtained by total volume integration. The on-column derivatization procedure was simple to perform, and it improved the sensitivity, the peak resolution, and the selectivity of the GC/MS determination.

Download Full-text

Direct ultrasound-assisted methylation of fatty acids in serum for free fatty acid determinations

Canadian Journal of Chemistry ◽

10.1139/v10-077 ◽

2010 ◽

Vol 88 (9) ◽

pp. 898-905 ◽

Cited By ~ 8

Author(s):

Liyan Liu ◽

Ying Li ◽

Rennan Feng ◽

Changhao Sun

Keyword(s):

Mass Spectrometry ◽

Fatty Acids ◽

Gas Chromatography ◽

Fatty Acid ◽

Fatty Acid Methyl Esters ◽

Methyl Esters ◽

Ultrasonic Waves ◽

Acid Methyl ◽

Ultrasound Assisted

A method for simultaneous determination of 16 free fatty acids (FFAs) in serum is described. The method involves conversion of FFAs to fatty acid methyl esters (FAMEs) using the heat of ultrasonic waves followed by gas chromatography and mass spectrometry (GC–MS) analysis. Optimum levels of the variables affecting the yield of FAMEs were investigated. The results indicate that the optimal levels are 55 °C, 60 W, 10% H2SO4/CH3OH, and 50 min. Recoveries ranged from 85.32% to 112.11%, with a detection limit ranging from 0.03 to 0.08 μg mL–1. The linearity, using the linear correlation coefficient, was higher than 0.9914.

Download Full-text

Determination of fatty acid methyl esters derived from algaeScenedesmus dimorphusbiomass by GC-MS with one-step esterification of free fatty acids and transesterification of glycerolipids

Journal of Separation Science ◽

10.1002/jssc.201601336 ◽

2017 ◽

Vol 40 (10) ◽

pp. 2214-2227 ◽

Cited By ~ 4

Author(s):

Satya Girish Chandra Avula ◽

Joanne M. Belovich ◽

Yan Xu

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Free Fatty Acids ◽

Fatty Acid Methyl Esters ◽

Methyl Esters ◽

Acid Methyl ◽

One Step

Download Full-text

Simultaneous Determination of Essential Oil Components and Fatty Acids in Fennel using Gas Chromatography with a Polar Capillary Column

Natural Product Communications ◽

10.1177/1934578x1501000933 ◽

2015 ◽

Vol 10 (9) ◽

pp. 1934578X1501000 ◽

Cited By ~ 2

Author(s):

Menče Najdoska-Bogdanov ◽

Jane B. Bogdanov ◽

Marina Stefova

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Essential Oil ◽

Simultaneous Determination ◽

Soxhlet Extraction ◽

Volatile Fraction ◽

Foeniculum Vulgare ◽

Oil Components ◽

Main Components

Cultivated and wild growing samples of fennel ( Foeniculum vulgare Mill., Apiaceae) from R. Macedonia were studied for their volatiles and fatty acid composition. The main essential oil components isolated via hydrodistillation were: trans-anethole (>80%), estragole (<6%), limonene (<6%), anisaldehyde (<1%) and 0.5 % fenchone. An alternative method for characterization of both the non-polar volatile and non volatile fractions was developed using n-hexane and dichloromethane (3:1, v/v) in a Soxhlet extraction followed by transesterification. The obtained extracts were then characterized and the dominant fatty acid was 18:1 (petroselinic and oleic acid) 75.0–82.8 %, followed by 18:2 (linoleic acid) 10.8–16.2% and other fatty acids: palmitic (4.3–6.9%), stearic (1.2–1.7%) and myristic (0–2.9%). The results for the volatile fraction after Soxhlet extraction and transesterification did not significantly differ from results obtained after hydrodistillation, especially for the main components ( trans-anethole, estragole, fenchone and limonene), implying that the developed method can be used for simultaneous determination of volatiles and fatty acids.

Download Full-text

Karakteristik Fisikokimia dan Identifikasi Komposisi Asam Lemak Minyak Testa Kelapa [Physicochemical Characteristics and Identification of Fatty Acid Composition Coconut Testa Oil]

Buletin Palma ◽

10.21082/bp.v21n2.2020.81-87 ◽

2020 ◽

Vol 21 (2) ◽

pp. 81

Author(s):

Ardi Kurniawan Makalalag ◽

Anton Muis ◽

Nicolas Tumbel

Keyword(s):

Fatty Acids ◽

Oleic Acid ◽

Fatty Acid ◽

Linoleic Acid ◽

Methyl Ester ◽

Lauric Acid ◽

Caprylic Acid ◽

Acid Methyl Ester ◽

Capric Acid ◽

Acid Methyl

Testa is a byproduct of the coconut flour industrial processing process and has not been used optimally. Testa is the outer layer of coconut flesh which is brown. peeled with a thickness of about 2mm, dried, and taken the oil. The purpose of this study was to see the potential that can be processed from coconut testa by identifying the physical and chemical properties of testa oil and to determine the composition of its fatty acid content. The research was carried out in 2019 and carried out at the Manado Industrial Research and Standardization Center Laboratory. The results showed a water content value of 0.2148%; free fatty acids 2.02%; the peroxide number is 0.4107 Mek O2/Kg; iodine number 14.452 g iodine/100g; and the saponin number 258.46 mg KOH/g. The results of testing the fatty acid composition of testa oil using a Gas Chromatography-Mass Spectrometry (GCMS) tool were obtained, eight types of fatty acids consisting of medium-chain fatty acids and long-chain fatty acids, with the most dominant percentage being Lauric acid methyl ester (C12 - Lauric acid) of 41.59% which is a group of medium-chain fatty acids. Overall, the fatty acids obtained are Caprylic acid methyl ester (C8 - caprylic acid) 5.43%, Capric acid methyl ester (C10 - capric acid) 4.68%, Lauric acid methyl ester (C12 - lauric acid) 41, 59%, Myristic acid methyl ester (C14 - myristic acid) 18.87%, Palmitic acid methyl ester (C16 - palmitic acid) 11.87%, Linoleic acid methyl ester (C18 - linoleic acid) 1.67%, Oleic acid methyl ester (C18 - oleic acid) 11.88%, Stearic acid methyl ester (C20 - stearic acid) 4.01%. The results obtained show that coconut testa oil has the potential to be developed into functional food, cosmetic and pharmaceuticals products .ABSTRAKTesta adalah produk samping dari proses pengolahan industri tepung kelapa, dan belum dimanfaatkan secara optimal. Testa merupakan lapisan luar daging buah kelapa yang berwarna coklat. dikupas dengan ketebalan sekitar 2mm, dikeringkan dan dikeluarkan minyaknya. Tujuan penelitian ini adalah untuk melihat potensi yang dapat diolah dari testa kelapa dengan cara mengidentifikasi sifat fisik dan kimia dari minyak testa dan untuk mengetahui komposisi kandungan asam lemaknya. Penelitian dilaksanakan pada tahun 2019 dan dilakukan di Laboratorium Balai Riset dan Standardisasi Industri Manado. Hasil penelitian diperoleh nilai kadar air 0,2148%; asam lemak bebas 2,02%; bilangan peroksida sebesar 0,4107 Mek O2/Kg; bilangan iod 14,452 g iod/100g; dan bilangan penyabunan 258,46 mg KOH/g. Hasil pengujian komposisi asam lemak minyak testa menggunakan alat Gas Chromatography-Mass Spectrometry (GCMS) diperoleh, delapan jenis asam lemak penyusun yang terdiri dari asam lemak rantai medium dan asam lemak rantai Panjang, dengan persentase yang paling dominan adalah Lauric acid methyl ester (C12 – Asam laurat) sebesar 41,59% yang merupakan golongan dari asam lemak rantai medium. Secara keseluruhan asam lemak yang diperoleh adalah, Caprylic acid methyl ester (C8 – asam kaprilat) 5,43%, Capric acid methyl ester (C10 – asam kaprat) 4,68%, Lauric acid methyl ester (C12 – asam laurat) 41,59%, Myristic acid methil ester (C14 – asam miristat) 18,87%, Palmitic acid methyl ester (C16 – asam palmitat) 11,87%, Linoleic acid methyl ester (C18 – asam linoleat) 1,67%, Oleic acid methyl ester (C18 – asam oleat) 11,88%, Stearic acid methil ester (C20 – asam stearat) 4,01%. Hasil yang diperoleh menunjukkan minyak testa kelapa memiliki potensi yang dapat dikembangkan menjadi produk pangan fungsional, kosmetik, maupun farmasi.

Download Full-text