GC-MS Instrument Research Articles

Dracorhodin: A potential marker compound for detecting the presence of dragon’s blood resin from Daemonorops originated from Indonesia

Waluyo TK, Wibowo S. 2018. Dracorhodin: A potential marker compound for detecting the presence of dragon’s blood resin from Daemonorops originated from Indonesia. Biodiversitas 19: 1665-1671. Dragon's blood typifies as red-colored resin, which is presented by several plant genus, i.e., Dracaena, Daemonorops, Croton, and Pterocarpus. In Indonesia, dragon's blood is originated from Daemonorops which grows scattered in Sumatera and Kalimantan islands. Relevantly, this study was conducted to identify the specific compounds of dragon's blood originated from Indonesia's Daemonorops. Dragon's blood test samples were originated from 16 different towns in Indonesia, which are known as the center of dragon's blood-production. The samples were in powder and solid formation. The compounds of samples were analyzed using GC-MS instrument. Results revealed that dragon's blood in powder and solid formation were inherently similar. Dragon's blood powder was obtained from wet extraction, while dragon's blood solid from dry extraction. Results of chemical analysis on 16 dragon's blood samples disclosed that three compounds were frequently detected associated with dragon's blood presence. Dracorhodin compound was detected in 16 dragon's blood samples i.e 3,4-dihydro-5-methoxy-6-methyl-2-phenyl-2H-1-benzopyran-7-ol in 13 samples; and trendione in 9 samples. Accordingly, dracorhodin could serve as the most compound containing in dragon's blood originated from Indonesia's Daemonorops, which could be observed from 16 tested Daemonorops dragon's blood samples from several regions (towns) in Indonesia.

Screening of Profiles of Essential Oils from the Aerial Parts of Sclerorhachis platy-rachis (Boiss.) Podlech ex Rech.f. Using Classical and Microwave-based Methods: Comparison with the Volatiles Using Headspace Solid-Phase Microextraction

Chemical profiles of the essential oils and volatile compounds from the aerial parts of Sclerorhachis platyrachis (Boiss.) Podlech ex Rech.f. obtained through hydrodistillation (HD), solvent-free microwave extraction (SFME), microwave assisted hydrodistillation (MAHD) and headspace solid-phase microextraction (HS-SPME) methods were subsequently investigated by means of GC and GC-MS instruments. Totally, 22, 29, 23 and 17 components were identified in the chemical profiles, representing 98.9%, 96.5%, 97.6% and 97.0% of the total compositions when using the HD, HS-SPME, SFME and MAHD methods, respectively. In all of the samples, more than fifty seven percent of the total structure consisted of monoterpene hydrocarbons. In addition, the second rank of the natural compounds was due to the oxygenated monoterpenes using the aforementioned techniques. β-Pinene was the main constituent in all chemical profiles, while the second rank was related to camphor with the exception of the volatile profile using the HS-SPME approach having more contents of α-pinene (13.4%) and limonene (9.7%) than camphor (8.2%).

Delta-7-stigmastenol: quantification and isomeric formation during chemical refining of olive pomace oil and optimization of the neutralization step

The aim of this study is to evaluate the formation of the increase of Δ-7-stigmastenol during the chemical refining of pomace olive oil (POO) and the optimal neutralization by NaOH concentration of 20 °Be at a temperature of 70 °C. A comparison has been made between virgin olive oil (VOO) and consecutive steps of refining process in the amounts of Δ-7-stigmastenol of the POO oil samples. Among the oils, refined olive oil particularly the neutralized olive oil (NOO) by soda (NaOH) contained a high-level of Δ-7-stigmastenol. A mean result found in NOO by different concentration of NaOH from 15 to 25 °Be showed increased values significantly (p < 0.05) from 0.70 ± 0.01% to 0.78 ± 0.01% of Δ-7-stigmastenol and increased significantly (p < 0.05) the levels of erythrodiol and uvaol from 26.34 ± 0.39% to 28.11 ± 0.42%. Then, the concentration of the ∆-7-stigmastenol was evaluated using a GC–MS instrument. Besides, further analyses were performed to ensure the uniqueness of the peak of Δ-7-stigmastenol and absence of any overlap. In all cases, the level of Δ-7-stigmastenol was higher than the limit set by the International Olive Council.

Enantiomeric Identification of Pregabalin by GC-MS via Methylation and S-TPC Chiral Derivatization.

Pregabalin is a Schedule V controlled substance which is defined as the (S) enantiomer of 3-(aminomethyl)-5-methylhexanoic acid. It is used legitimately to treat neuropathy in patients with diabetes as well as for epilepsy and fibromyalgia. Pregabalin is an amino acid and an amphoteric compound, which makes it difficult to analyze using the conventional GC-MS instrumentation found in most forensic drug analysis laboratories. Problems associated with the traditional GC-MS analysis of pregabalin include selective solubility, ring closure to the corresponding lactam in the GC injection port and/or the MS transfer line and difficulty with chiral derivatization due to the presence of a carboxylic acid moiety. Here, we show that these challenges can be overcome by methylating (capping) the carboxylic acid portion of the pregabalin molecule and converting to the corresponding methyl ester. Once the methyl ester is synthesized, chiral derivatization at the amine can be achieved to identify the controlled (S) enantiomer of pregabalin via GC-MS.

Produksi Etil Ester Dari Minyak Dedak Padi (Oryza Sativa) Menggunakan Reaktor Ultrasonik

Indonesia as the third largest grain producer in the world produces large amounts of bran. High contain Free Fatty Acid (FFA) in rice bran oil causes it can be converted into the fatty acid ethyl esters (biodiesel) by esterification and transesterification methods. The rice bran oil was obtained by rice bran extraction using n-hexane. The esterification process was catalyzed by HCl. In this study, the transesterification process to convert triglycerides into ethyl esters (biodiesel) was conducted by the addition of KOH as a neutralizer and a catalyst Oil and ethanol by ratio 1:6 using 0,5% KOH as catalysator were reacted by utilizing 47 kHz ultrasonic wave for 45, 60 and 75 minutes. Biodiesel conversion value obtained were 49,23%; 70,55% and 52,04% respectively. Biodiesel product spectrum was analyzed using FTIR and GCMS instrument. The density, viscosity and flash point is also measured. FTIR analysis on all variations give similar data spectrum, where the ethyl ester products are characterized by typical bands at specific frequencies such as -C=O; -C-C; -C-H (sp3) and = C-H (sp2) stretch. Based on the data from GCMS spectrum, the product components are ethyl palmitate, ethyl linoleate, ethyl stearate and ethyl oleate.

Recent Modifications and Validation of QuEChERS-dSPE Coupled to LC-MS and GC-MS Instruments for Determination of Pesticide/Agrochemical Residues in Fruits and Vegetables: Review.

Fruits and vegetables constitute a major type of food consumed daily apart from whole grains. Unfortunately, the residual deposits of pesticides in these products are becoming a major health concern for human consumption. Consequently, the outcome of the long-term accumulation of pesticide residues has posed many health issues to both humans and animals in the environment. However, the residues have previously been determined using conventionally known techniques, which include liquid-liquid extraction, solid-phase extraction (SPE) and the recently used liquid-phase microextraction techniques. Despite the positive technological effects of these methods, their limitations include; time-consuming, operational difficulty, use of toxic organic solvents, low selective property and expensive extraction setups, with shorter lifespan of instrumental performances. Thus, the potential and maximum use of these methods for pesticides residue determination has resulted in the urgent need for better techniques that will overcome the highlighted drawbacks. Alternatively, attention has been drawn recently towards the use of quick, easy, cheap, effective, rugged and safe technique (QuEChERS) coupled with dispersive solid-phase extraction (dSPE) to overcome the setback challenges experienced by the previous technologies. Conclusively, the reviewed QuEChERS-dSPE techniques and the recent cleanup modifications justifiably prove to be reliable for routine determination and monitoring the concentration levels of pesticide residues using advanced instruments such as high-performance liquid chromatography, liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry.

The Effect of Acetone Amount Ratio as Co-Solvent to Methanol in Transesterification Reaction of Waste Cooking Oil

The production of biodiesel from waste cooking oil by transesterification reaction using acetone as co-solvent has been carried out. This research studied the optimal amount ratio of acetone as co-solvent to methanol in the transesterification process using homogeneous alkaline catalyst KOH 1% (w/w) of waste cooking oil at room temperature for 15 minutes of reaction time. Mole ratio of waste cooking oil to methanol is 1:12. Acetone was added as co-solvent in varied amount ratio to methanol are 1:4, 1:2, and 1:1, respectively. The results of fatty acid methyl esters (FAME) were analysed using GC-MS instrument. The results showed that the optimal ratio is 1:4 with 99.93% of FAME yield.

Development of Candidate Reference Materials of Endosulfan Sulfate and Bifenthrin in Black Tea

The candidate reference materials of endosulfan sulfate and bifenthrin in black tea have been developed according to the requirements of ISO Guide 34 and 35. Preparation of candidate material includes grinding and sieving of the black tea leaves, spiking the black tea powder by both analytes, homogenization, and bottling. Homogeneity and short-term stability test were performed using a GC-µECD instrument. Meanwhile, the characterization was carried out by a collaborative study using both of GC-µECD and GC-MS instruments. The uncertainty budget was evaluated from sample inhomogeneity, short-term instability and variability in the characterization procedure. In a dry mass fraction, endosulfan sulfate was assigned to be 491 µg kg-1 with a relative expanded uncertainty of ± 33.2%, and bifenthrin was assigned to be 937 µg kg-1 with a relative expanded uncertainty of ± 18.5%. The candidate reference materials are aimed to support the need of matrix CRM especially for the measurement of pesticide residue for quality assurance work done by laboratories in Indonesia.

Mapping Perfluoroalkyl Effects in Togni-Type Reagents by Thermolysis.

We present the thermolysis of cyclic hypervalent iodine(III) perfluoroalkyl transfer reagents carried out in standard GC-MS instrumentation. Through heating, these structures undergo fragmentation to afford perfluoroalkyl radicals F2n+1 Cn. and each reagent can be characterized by means of a threshold temperature, TIP (n). This parameter TIP (n) not only reflects the stability of the F2n+1 Cn -I bond, but potentially also carries information regarding fundamental properties of the linear perfluoroalkyl chains.

Novel high value elemicin-rich germplasm of lemon grass (Cymbopogon khasianus (Hack)Stapf(ex Bor) from North East India

Genus Cymbopogon is a valuable medicinal and aromatic grass of the world. The objective of the experiment was to identify elemicin rich genotype of Cymbopogon khasianus. Elemicin is widely used as a perfumery chemical as well as starting material for the synthesis of mescaline, an important alkaloid. Moreover it can also be used in confectionery, condiments, non-alcoholic beverages etc. In this experiment total forty eight accessions of Cymbopogon khasianus were collected from different parts of Meghalaya and planted in complete randomized block design with three replications at experimental farm of CSIR-NEIST in the year 2013.Morphological data recording and its oil constituents were analysed during the year 2013–14 and 2014–15. On the basis of two years selection trial data a new and distinct elemicin rich strain of Cymbopogon khasianus was identified and named as Jor Lab L-10. This new genotype was planted in the year 2015–16 and 2016–17 in multi-location trials at four different locations and the results were found to be stable and contented. The average oil yield of all multi-location trial was 0.40% which comprises of 70% elemicin content and 175% superior in the term of elemicin content from the check variety. Essential oil was extracted through hydro distillation method and the quantification was done by GC and GC–MS instrument. In GC and GC–MS analysis it was found that elemicin was the major component of essential oil while cis-asarone, β-ocimene, methyl eugenol, limonene, germacrene-D, transneral acetate, camphene, α-pinene, geranyl acetate, caryophyllene and trans-β- farnesene etc. were the minor compounds. Till date none of the elemicin rich (>70%) variety of lemon grass is reported and we first time identified a novel elemicin rich variety.

Kopling Oksidatif Eugenol Menggunakan Ekstrak Enzim Peroksidase dari Akar Tanaman Sawi Hijau serta Uji Bioaktivitasnya

Peroxidase has been successfully extracted and partially purified from Brassica juncea L. Czern root with protein content and specific activity of 0.747 mg/mL and 0.244 U/mg, respectively. Then, it was applied as biocatalyst for green oxidative coupling reaction of eugenol to produce an orange crystal, dimeric form of eugenol (84% yield). Structure elucidation was done by using FTIR, UV-Vis and GC-MS instruments. The optical activity of dimeric eugenol was found to have Ra-configuration. Furthermore, biological activity of the product as antioxidant has been evaluated resulting in IC50 values of 32.14 and 42.43 ppm for dimeric and monomeric eugenol, respectively.

Phytotoxic effects of several essential oils on two weed species and Tomato

Abstract Essential oils (EOs) composition of Rosmarinus officinalis L., Satureja hortensis L. and Laurus nobilis were analyzed by GC and GC–MS instrument. Then phytotoxic activities of mentioned EOs and a combination of R. officinalis and L. nobilis EOs (R+L) were evaluated against germination and growth of two weeds species, A. retroflexus (dicot), B. tectorum (monocot) and tomato. Applied EOs strongly inhibited the germination and seedling growth of the tested species, in a dose dependent manner with A. retroflexus being significantly more sensitive than others. Indeed, at 400 μ L . L − 1 EO of R. officinalis, germination of A. retroflexus decreased 91.3%, while for the same dose, germination and seedling growth of B. tectorum and tomato were reduced by 56.7% and 26.7%, respectively, compared with control. R. officinalis EO caused the most germination inhibitory for A. retroflexus and tomato while B. tectorum germination was well inhibited by S. hortensis EO. Seedling growth were also affected by EO application in a dose response manner. A. retroflexus shoot length was inhibited by the R+L EO more than other EOs while most root growth inhibition caused by S. hortensis EO. For B. tectorum, and tomato, S. hortensis had the strongest inhibitory effect on root and shoot elongation.

The Effect of pyrolysis conditions to produce levoglucosan from rice straw

The industrial sectors that produce synthetic chemicals and and polymers rely heavily on fossil resources. Rice straw is very abundant in Indonesia and can be used as a substitute for fossil resources to produce petrochemical precursors. It is known that cellulose component is the main source for LG formation. Due to high contain of cellulose, the potential of rice straw can be transform by pyrolysis to produce bio-oils and derivative products towards levoglucosan (LG) should be developed. Levoglucosan is an important intermediate compound as it can be convert to the precursor of bio-polymer adipic acid, bio-ethanol, etc. Nowadays it’s still rarely research focused on this mechanism route producing LG through pyrolysis. LG then can run into a further reaction and produce derivative products. In order to obtain the highest yield of LG in bio-oil, a condition that may inhibit the further reaction of LG during pyrolysis takes place. The factor of biomass source and composition, temperature, and holding time (adjusted by N2feed) most likely greatly affect the product composition formed at the end of pyrolysis. In this study, fast-pyrolysis of rice straw was performed in fixed-bed reactor (5 grams of biomass) under different temperature ranges (450 to 600 °C), N2flow rate (1200 to 1582 ml/min) to maximize the yield of LG. The content of LG on bio-oil was measured by GC-MS instrument. The maximum yield of LG (67.78% of area) was obtained at an optimal temperature of 500°C with holding time of 1.35 s.

Establishment of a reference standard database for use in the qualitative and semi-quantitative analysis of pharmaceutical contact materials within an extractables survey by GC–MS

The analysis of reference standards may be performed to enhance the qualitative and quantitative data generated by non-specific screening methods utilized in extractables studies performed on pharmaceutical contact materials. However, the establishment of a database containing relative response factor and retention index values obtained from these standards has not been published. In this study, the establishment of such a database for GC–MS, a methodology commonly included in extractables studies, on an intra-lab basis was investigated. A set of 154 organic compounds representing a diverse range of chemical functionalities and properties was analyzed at eight time points on four GC–MS instruments that represent the diversity of age and model at our laboratory. The results of this study have shown that any variance in relative response factor between instruments was not significant from a practical perspective as supported by the coefficient of variation values (n = 32), which were ≤15% and ≤10% for 75% and 45% of the compounds tested, respectively. Furthermore, the retention index of the compounds, as expressed by retention time and relative retention time, did not have more than a 2% coefficient of variation between instruments or columns in most cases. It was concluded that a database of these values could be established for future use in extractables studies on an intra-laboratory basis.

HYDROGENATION OF CITRONELLA OIL DERIVATIVES TO 3,7-DIMETHYL-1-OCTANOL AS POTENTIAL BIO-BASED ADDITIVES OVER MODIFIED NATURAL ZEOLITE CATALYSTS

An alternative way for saving energy and reduce emission in fuel consumption is using oxygenate compounds as fuel additives that can reduce carbon monoxide and soot that is created during the burning of the fuel. One derivatives of citronella oil fraction, 3,7-dimethyl-1-octanol, is a potential alcohol compound for fragrance and fuel additives producing efficiency energy and environmentally friendly. In this research, the conversion of citronella oil fraction (containing&gt; 60% citronellal) into 3,7-dimethyl-1-octanol was investigated using Ni based natural zeolite-Bogor (ZAB) catalysts through hydrogenation process. The structure and properties of the Ni/ZAB catalysts have been investigated extensively using some of characterization techniques for solid materials i.e. XRF and TEM. Variations of weight catalysts and temperature reaction were conducted to determine the optimum conditions for this reaction. The products were analyzed using GC-MS instrumentation. The optimum conditions for the hydrogenation of citronella oil fractions using catalysts Ni / ZAB-20wt% -HT were obtained at 300oC with 10% weight of catalysts produced 12% of the 3,7-dimethyl-1-octanol compound.

GC-MS analysis and antimicrobial activity determination of Citrus medica L. var proper leaf essential oil from South Sulawesi against skin pathogen microorganism

A research about Citrus medica L. var sarcodactylis had been conducted and it showed a significant antimicrobial activity, thus drive our curiosity to investigate the other variety from the same species, Citrus medica L. var proper. This research focuses in chemical compound study and antimicrobial activity screening against Staphylococcus aureus, Propionibacterium acne, and Candida albicans of Citrus medica L. var Proper leaves’ essential oil. The essential oil is distillated from fresh leaves by hydrodestillation. The chemical compound was analysed using GC-MS instrument while the antimicrobial activity was tested using disk diffusion method. The results showed that the major component of the essential oil was Z-citral, citral and limonene compounds. The antimicrobial activity test results against the test microorganism are 9.15±0.15 mm, 11.15±1.3 mm and 8.02±0.48 mm, consecutively, for Staphylococcus aureus, Propionibacterium acne and Candida albicans.

Analisis Komposisi Kimia Daun Kelakai (Stenochlaena palustris Bedd.) dengan Berbagai Pelarut menggunakan GCMS (Chemical Composition Analysis of Stenochlaena palustris Bedd. Leaves using Various Solvents on GCMS)

The selection of suitable solvents is essential for extracting the desired compounds from plant cells. GCMS is an instrument that can be used to identify such compounds. Therefore, this study objective is to extract kelakai leaves using various solvents and analyze the composition of chemical compounds using GCMS instrument. Kelakai leaves was extracted using three solvent variations: a1 = aquadest, a2 = ethanol, and a3 = ethanol 50%; and the maceration time variations: b1 = 1 day, b2 = 2 days, and b3 = 3 days. The best extraction method was aquadest as solvent and one day maceration. The chemical compound extracted were phenolic, alkaloids and terpenoids, such as 2,5-bis [(trimethylsilyl) oxy] benzaldehyde 1,86%, linalool 1,28%, phenethyl alcohol 3,55% and 7-chloro-5-phenyl-1-(trimethylsilyl)-1,3-dihydro-2H-1,4-benzodiazepines-2-on 1,16 % db.Keywords: composition analysis, GCMS, maceration, Stenochlaena palustris Bedd.

Metabolite Variation of Peanut Hulls (Arachis hypogaea L.) from Three Locations of Lombok Island on the Basis of GC-MS Analysis

This article is a part of studies to investigate the potential of natural products from Lombok Island for antidiabetic agents. This study was directed to learn the metabolite variations of peanut hulls collected from three different locations in Lombok Island. The hull samples were extracted in methanol, followed by partition process into three fractions using three solvents with varied polarities (dichloromethane, hexane and acetone). The fractions were then separated and identified for their chemical composition by using GC-MS instrument. Metabolite variations of three extracts showed that the antidiabetic compounds stigmast-5-en-3-ol and oleic acid were found in all three locations with different percentages of abundance. Another antidiabetic compound, linoleic acid, was only identified in peanut hulls from the village of Pringga Jurang (PJ). Besides the antidiabetic compounds, there were other major compounds with known biological activities discussed to find other uses of the hulls.

Produksi DAG Dari Virgin Coconut Oil (VCO) Melalui Reaksi Trans-Esterifikasi Menggunakan Enzim Lipase Dedak Padi (Oryza Sativa L.) Spesifik C18-20 Terimobilisasi Karbon Aktif Sebagai Biokatalis

This research aims to produce DAG of the VCO through the substrate reaction of trans-esterification using lipase enzymes specifically C18-20 from rice bran (Oryza Sativa L.) immobiled of activated carbon as a catalyst. Phases of this research starts with the enzyme lipase do immobile using activated carbon; next enzymes of immobile used to produce DAG through the trans-esterification reaction using a VCO as a substrate and methanol as ko-substrate; DAG and methyl ester produced identified using FTIR instrument and GC-MS instruments. The results showed that there were three compounds DAG and three compound methyl ester produced trans-esterification reaction, namely (1) 1-laurin, 3-heksanoin esters of glycerol; (2) 2-laurin, 3-oktanoin esters of glycerol; (3) 1-laurin, 3-heksanoin esters of glycerol; (4) methyl ester oleic; (5) methyl ester stearic acids; and (6) methyl ester arachidat.

Determination of trace amounts of chlorobenzenes in water using membrane-supported headspace single-drop microextraction and gas chromatography–mass spectrometry

A novel method based on the coupling of membrane-supported headspace single-drop microextraction with gas chromatography‒mass spectrometry (GC–MS) is developed for the determination of chlorobenzenes in water samples. For the determination of five chlorobenzenes, a 15 μL toluene microdrop was placed inside the plastic membrane and exposed for 10 min for headspace extraction while stirring at 1000 rpm. The microdrop was then picked up by a microsyringe and directly injected into the injector block of the GC–MS instrument. Under the optimized operation conditions, the calculated calibration curves gave a high level of linearity for all targets with correlation coefficients range from 0.9945 to 0.9987. The limits of detection range from 0.01 to 0.05 μg/L and the RSDs for most of chlorobenzenes were below 7%. The method is simple, sensitive, and stable for single drop microextraction. Its applicability is demonstrated by the determination of chlorobenzenes in tap water samples.