Gas Chromatography Coupled With A Flame Ionization Detector Research Articles

The presence of polycyclic aromatic hydrocarbons (PAHs) in air particles and estimation of the respiratory deposition flux

Polycyclic aromatic hydrocarbons (PAHs) in the atmospheric particles constitute a topic of growing health concern. This study aims to calculate PAH concentrations, identify the source, assess the health risk from exposure to carcinogenic PAHs, and the respiratory deposition flux. PM10 and PM2.5 were collected in September 2019 in the urban, semi-urban, and semi-urban-industrial areas of Kuala Lumpur, Batu Pahat, and Bukit Rambai, respectively. A total of 18 PAHs from PM10 and 17 PAHs from PM2.5 were extracted using dichloromethane and determined using gas chromatography coupled with a flame ionization detector (GC-FID). The health risk assessment (HRA) calculated included B[a]P equivalent (B[a]Peq), lifetime lung cancer risk (LLCR), incremental lifetime cancer risk (ILCR), and respiratory deposition dose (RDD). The results show PAHs in PM10 recorded in Kuala Lumpur (DBKL), Batu Pahat (UTHM), and Bukit Rambai are 9.91, 8.45, and 9.57 ng/m3, respectively. The average PAHs in PM2.5 at the three sampling sites are 11.65, 9.68, and 9.37 ng/m3, respectively. The major source of PAHs obtained from the DRs indicates pyrogenic activities for both particle sizes. For PM10, the total B[a]Peq in DBKL, UTHM, and Bukit Rambai were 1.97, 1.82, and 2.32 ng/m3, respectively. For PM2.5 samples, the total B[a]Peq in DBKL, UTHM, and Bukit Rambai were 2.80, 2.33, and 2.57 ng/m3, respectively. The LLCR and ILCR show low to moderate risk for all age groups. The RDD of adults and adolescents is highest in both PM10 and PM2.5, followed by children, toddlers, and infants. Overall, we perceive that adults and adolescents living in the urban area of Kuala Lumpur are at the highest risk for respiratory health problems because of prolonged exposure to PAHs in PM10 and PM2.5, followed by children, toddlers, and infants.

Magnetic solid-phase extraction of polycyclic aromatic hydrocarbons from water samples using magnetic carbon nanofiber/MIL-101(Cr) nanocomposites.

In this study, magnetic carbon nanofibers (Fe3O4@CNF) were modified with MIL-101(Cr) (Fe3O4@CNF@MIL-101) and used as sorbents for magnetic solid-phase extraction (MSPE) to extract polycyclic aromatic hydrocarbons (PAHs) from real water samples. Gas chromatography coupled with a flame ionization detector (GC-FID) was used for the determination of the PAHs. The effect of experimental variables on the extraction efficiency of PAHs was investigated and optimized. These variables include the quantity of sorbent, the kind and volume of the elution solvent, the duration of extraction and desorption, and the salt concentration. The linear range was found to be 0.01 to 200 ng mL-1 with correlation coefficients ranging from 0.9906 to 0.9931 after the effective extraction parameters were optimized. Its detection limits (LOD) were also calculated to be between 0.003 and 0.005 ng mL-1 (S/N = 3). The method's repeatability was tested at three different concentration levels (0.1, 1, and 10 ng mL-1), and relative standard deviations (RSDs%) were obtained in the range of 2.3 to 5.0%. Finally, using the MSPE-GC-FID method, PAHs were extracted from tap water, wastewater, seawater, and spring water samples. The relative recoveries were in the range of 95.7 to 99.8%.

Quality index based on fatty acids for Syrian pistachio cultivars (Pistacia vera L.) grown in Mascara (North-West of Algeria)

<p class="042abstractstekst">Pistachio (<em>Pistacia vera</em> L.) is one of the most important hard-shelled nuts all over the world. Pistachio has a very high nutritional value with its quality index based on fatty acids composition, protein, mineral, vitamin-E, and antioxidant contents. In the current study, fatty acids values of the Syrian pistachio varieties cultivated in Algeria (‘Adjmi’, ‘Bayadhi’, ‘Batouri’, ‘Achouri,’ and ‘Neb-djemel’) were detected for the first time. Oil extraction of cultivars was performed using n-hexane in a Soxhlet apparatus, and the fatty acids composition of the oil was analyzed by gas chromatography coupled with a flame ionization detector (GC/FID) in the methyl ester form. The fatty acid composition of the pistachio cultivars was detected as: palmitic acid (8.23 % ± 0.36 to 9.49 % ± 0.07), palmitoleic acid (0.10 % ± 0.02 to 0.62 % ± 0.24), stearic acid (0.67 % ± 0.04 to 1.40 % ± 0.18), oleic acid (56.35 % ± 2.13 to 61.90 % ± 1.07), linoleic acid (19.48 % ± 0.27 to 26.76 ± 0.55) and linolenic acid (0.390 % ± 0, 03 to 0.59 % ± 0.01) in all samples. The results demonstrated that the five pistachio cultivars were rich in monounsaturated fatty acids (MUFA) (56.9 7% ± 1.88 to 62.10 % ± 1.02) and moderately low in saturated fatty acids (SFA) (9.90 % ± 0.04 to 10.37 % ± 0.23). ‘Adjmi’ has fatty acid composition lower than the other cultivars statically. Oleic acid value was determined higher than other fatty acid components. In the current study, the fat and fatty acid components of pistachio cultivars were determined and the results of this study can be used for future pistachio breeding programs.</p>

Investigations of the Chemical Composition and Aromatic Properties of Peel Essential Oils throughout the Complete Phase of Fruit Development for Two Cultivars of Sweet Orange (Citrus sinensis (L.) Osb.).

The peel essential oil (PEO) of sweet orange is used for flavoring liquors or foods and in the perfumery and cosmetics industry. The fruit maturity stage can modify the essential oil composition and aromatic properties, but little information is available on the evolution of PEO during the entire time set of fruit development. In this study, the yield, chemical composition and aromatic profile over the three phases of orange development were monitored. Four fruit traits (peel color, weight, acidity and sweetness) were recorded to characterize fruit development. Fruits of two sweet orange cultivars were sampled every two weeks from June to May of the next year. PEO was obtained by hydrodistillation and analyzed by gas chromatography coupled with a flame ionization detector (GC-FID). Compounds were identified with GC coupled with mass spectrometry (GC/MS). Ten expert panelists using the descriptor intensity method described the aromatic profile of PEO samples. The PEO composition was richer in oxygenated compounds at early fruit development stages, with an aromatic profile presenting greener notes. During fruit growth (Phases I and II), limonene’s proportion increased considerably as a few aliphatic aldehydes brought the characteristic of orange aroma. During fruit maturation (from November to March), the PEO composition and aromatic profile were relatively stable. Later, some modifications were observed. Regardless of the fruit development stage, the two sweet oranges presented distinct PEO compositions and aromatic profiles. These results constitute a temporal reference for the chemical and aromatic evolution of sweet orange PEO in the fruit development process under Mediterranean conditions. During the first two phases of fruit development, many changes occur in the PEO composition and aroma, suggesting that their exploitation could create new products.

Changes in Fusarium and Aspergillus Mycotoxin Content and Fatty Acid Composition after the Application of Ozone in Different Maize Hybrids.

Mycotoxins in maize represent a great threat to human health. For this reason, novel technics such as ozone treatment are used to reduce the content of maize mycotoxins. However, there is little knowledge about the effect of ozone treatment on maize quality parameters. This study investigated the changes in Fusarium and Aspergillus mycotoxins and the changes in fatty acids during the ozone treatment of maize samples. Sixteen maize hybrids were visually tested for the naturally occurring ear rot severity and treated with three different concentrations of ozone (40, 70, and 85 mg/L). Mycotoxin content in maize samples was determined using a high-performance liquid chromatography (HPLC) system, whereas dominant fatty acids were determined using gas chromatography coupled with a flame ionization detector (GC-FID). Ozone treatments could be successfully applied to reduce the content of mycotoxins in maize below the detection limit. Ozone treatments increased the content of monounsaturated fatty acids (MUFAs) and decreased the content of polyunsaturated fatty acids (PUFAs), i.e., linoleic acid (36.7% in relation to the lowest applied ozone concentration), which negatively affected the nutritional value of maize.

Optimization of Determination Method of Cooling Agents in Cigarette Tipping Paper by Gas Chromatography

Monitoring the characteristic components in tipping paper is important to ensure the quality of cigarette products. This study establishes a method based on gas chromatography (GC) for determining cooling agents in tipping paper. The tipping paper was cut into pieces and extracted by ethanol under specific temperatures in a shaker. Then, the characteristic cooling agents of (-)-menthone, L-menthol, and (-)-menthyl lactate in extract were determined using GC coupled with a flame ionization detector (GC-FID). The limits of detection (LODs) and limits of quantification (LOQs) for the three cooling agents ranged from 0.15~0.32 μg/mL and 0.49~1.06 μg/mL, respectively. Results demonstrated a good linear relationship with high correlation coefficients for the three tested cooling agents. The extraction conditions of the cooling agents were optimized through a single-factor experiment as well as an orthogonal experiment. The standard addition recovery experiment showed that the average recoveries range from 81.23 to 100.62%, and the relative standard deviations (RSDs) of the measured values (n = 5) ranged from 0.34 to 1.64%.

Comparison of analytical methods for the fatty acid profile in ewes' milk.

Studies comparing methodologies for fatty acids are very important, since they can influence the quality and final quantification of the lipid fraction. Objective—to compare different extraction methods for total lipids and to evaluate the effect of these methodologies on the quantitative composition of fatty acids in milk of lactating ewes raised in tropical pastures. The methodologies used were simple direct transesterification, using the HPLC grade organic solvent n-hexane, Bligh; Dyer (cold extraction, extracting mixture proportions 5, 10, and 15 mL in a ratio of 2:1:1 (v/v/v) of chloroform-methanol-water). The fatty acid methyl esters were separated by gas chromatography coupled with a flame ionization detector (GC-FID). The results show that there was no significant difference (p <0.05) in the total lipid content between the extraction methods. However, the Bligh’s method; Dyer obtained the best yield of lipids to be extracted from ewe’s milk, since the volume with 15 mL of the extraction solution was able to identify 87% of the chromatographic peaks. It was also observed that ewe’s milk has a higher percentage of palmitic, stearic and oleic fatty acids, with percentages of 20.1%, 15.5% and 33.1%, respectively. Therefore, an extraction mixture with a volume of 15 mL used in this study may be an alternative to perform the extraction of milk fat from high lactating ewes in tropical pastures as a routine method, as it expresses the best lipid content of this food.

GC-MS and GC-FID analyses of the essential oil of Eucalyptus camaldulensis grown under greenhouses differentiated by the LDPE cover-films

The chemical composition of essential oils (EOs) can vary from one plant to another of the same species and can be affected by several factors including the environment of growth. The research was carried out on the EOs of Eucalyptus camaldulensis leaves grown in three separate greenhouses differentiated by their low-density polyethylene (LDPE) covering material. This study aimed to compare the impact of the type of the greenhouse cover film on the internal microclimate, light intensity, and chemical composition of E. camaldulensis EOs. Eucalyptus species was initially cultivated from the seeds and the EOs were extracted from the leaves of 14 weeks aged trees. The extraction was performed by hydrodistillation using a Clevenger-type apparatus. Qualitative and quantitative analyses of the extracted EOs were performed using gas chromatography coupled with mass spectrometry (GC-MS) and gas chromatography coupled with a flame ionization detector (GC-FID). The analyzed samples were rich in terpenes with a total of 66 identified compounds. The oxygenated monoterpenes pinocarvone and D-carvone were only identified in the essential oils from multilayered greenhouses. cis-1-Methyl-4-(1-methylethyl-)-2-cyclohexen-1-ol was absent in eucalyptus EOs from the three-layer greenhouse, unlike the others that had it. Different compound contents were detected in the extracted essential oils, according to their greenhouse cover conditions. 1,8-Cineol was the compound present in a higher amount as expected, with the highest value of c.a 164.78 mg/gdw from the leaves of E. camaldulensis cultivated in the ordinary greenhouse. Contents of 51.55 mg/gdw and 42.11 mg/gdw were obtained from E. camaldulensis cultivated in the three-layers and monolayer greenhouses, respectively. In contrast, the EOs of E. camaldulensis grown under the monolayer greenhouse presented the highest content of some aromadendranes family compounds. This study shows that the greenhouse cover-film should be chosen thoughtfully because it plays a major function regarding its effect on the chemical composition of the EOs of E. camaldulensis cultivated in greenhouse environments.

Comparative analysis of groundwater quality statuses and associated health risk indices of metals and total hydrocarbons at locations of tank farm in Delta State, Nigeria

The study aimed at assessing the groundwater quality and the associated health implications of oil storage tank farms in Asaba, Oghara, Warri, and Koko towns, in Delta State, Nigeria. Fe, Cr, Cd, Ni, Pb, and V concentrations in the groundwater samples were determined using Atomic Absorption Spectrophotometry (AAS), while total hydrocarbons (THC) concentrations were determined using gas chromatography coupled with a flame ionization detector (GC-FID). The quality index of Warri groundwater was 66.38; being within the range of 51–75 was considered poor quality. The water quality indices (WQI) of Oghara, Koko, and Asaba were 163.79, 161.43, and 129.95 respectively, which were all > 100, hence amounting to very poor water quality status. Results indicated that children in Oghara who are orally exposed to chromium are at risk of cancer. Both adults and children orally exposed to THC in Oghara are also at risk of cancer. Furthermore, THC posed an oral route cancer risk to the children in Koko town. The study showed that chromium posed carcinogenic threats to children in Oghara, while THC posed carcinogenic threats to adults and children in Oghara and children alone in Koko. These risks are liable to be mediated through ingestion of the groundwater of Oghara and Koko by the susceptible groups.

Fatty acid profile of lipid-rich food consumed in Paraguay

The present study aims to establish the fatty acid profile of a variety of traditional foods consumed regularly in Paraguay. Thirty-two high-lipid content foods were evaluated by gas chromatography coupled with a flame ionization detector (GC-FID). Meat and dairy products were found to present high levels of saturated fatty acids, and this led to an increase in the atherogenicity and thrombogenicity indices of these products. Among the monounsaturated acids evaluated, oleic acid (18:1n-9c) was mainly found in olives (71.7%) and chipa (62.7%), which had been industrially prepared with the addition of oleic acid. Milk-based ice cream (5.1%) and chipa guazú (3.8%) presented the highest content of trans fatty acids. The n-6/n-3 fatty acids ratio obtained for the traditional sopa Paraguaya and empanada (fried pasty) was higher than 37:1; this can be attributed to the addition of soybean and corn oils in the preparation of these foods. The data evaluated and presented in this study can contribute toward the improvement of eating habits among the Paraguayan population, as well as help combat the risk factors commonly associated with bad eating habits and chronic health issues.

Multi-residue analysis of pesticides in blood plasma using hollow fiber solvent bar microextraction and gas chromatography with a flame ionization detector

The challenges faced on pesticide extraction from biological samples are finding a method that allows a multi-residue extraction, pre-concentration, clean-up, and isolation of analytes in just one step. In this sense, the hollow fiber – liquid phase microextraction method (HF- LPME) in the "solvent bar" mode was used to optimize and validate a method for pesticide multi-residue analysis in blood plasma at trace levels, through gas chromatography coupled with a flame ionization detector (GC-FID). Hollow fiber solvent bar microextraction HF-SBME was carried out with octanol immobilized into the pores of hydrophobic polypropylene fiber and disposed within a matrix of blood plasma, spiked with a mixture of pesticides (monocrotophos, lindane, aldrin, methyl parathion, endosulfan, dieldrin, DDD, DDT, and endrin). The optimization parameters evaluated were: extraction temperature and time, stirring speed, and salt concentration. A principal component analysis was performed to visualize the analytes' behaviour based on their explained variance, and then, a Box-Behnken analysis was generated to identify the optimum parameters. According to the PCA, all pesticides showed similar responses to the extraction method and the response of dieldrin exhibit the lowest variance. Moreover, the stationary points selected from the Box-Behnken analysis were 25.5 °C for the extraction temperature, 870 rpm for stirring speed, 16 min for extraction time, and 8.3 % w/v of salt concentration. Moreover, the validation results proved that HF-SBME is an alternative technique for pesticide multi-residue extraction in blood plasma. The analytes were able to concentrate, reaching 46 fold enrichment. The solvent type, sample and solvent volume were narrowed down without changing the method's precision or accuracy. The relative standard deviation was under 10 %, and the recovery was between 55 % and 105 % for the different analytes excepting lindane, which had lower recovery (27 %). The detection limits were 0.02 until 0.13 μg mL−1 for most of the pesticides used. Finally, HF-SBME is a good alternative for pesticide multi-residue extraction in complex matrices like plasma.

OPTIMIZATION OF EXTRACTION CONDITIONS OF VOLATILE COMPOUNDS OF ROASTED BEEF BY SOLID-PHASE MICROEXTRACTION

Aroma is one of the most important sensory attributes for acceptance by beef consumers. The first step in analysing the volatile compounds associated with this attribute is their extraction from the food matrix, solid-phase microextraction has been widely used for volatile compound determination in meat. This study aimed to test six different solid-phase microextraction (SPME) fibre coating materials for their volatile compounds extraction efficiency for roasted beef and to optimize the extraction conditions using response surface methodology. Gas chromatography coupled with a flame ionization detector (GC-FID) and mass spectrometry (GC-MS) were used. The choice of SPME fibre coating was based in the total area obtained by GC-FID analysis for the six fibre coatings. The optimum time and temperature for SPME extraction was 60 °C/65 minutes. The mixed-phase fibre coatings showed the best results for extracting volatile compounds in roasted beef as higher number of compounds were identified. The carboxen/polydimethylsiloxane (CAR/PDMS) fibre extracted the largest number of compounds under the optimum extraction condition. Aldehydes were the predominant class of compounds found in roasted beef, followed by alcohols and hydrocarbons.

Effect of photocatalytic pretreatment on the biodegradation of n-hexane vapours in a biofilter

Hydrophobic volatile organic compounds (VOCs) such as n-hexane are not completely biodegradable by a single biofilter. So, in the present study, a photoreactor system packed with scoria granules coated with TiO2, as a pretreatment unit, was used for increasing the removal efficiency of n-hexane by a biofilter during an operation period of 191 days. The inlet and outlet concentration of n-hexane was analyzed with a gas chromatography coupled with a flame ionization detector (GC/FID). The results indicated that the removal efficiency of the single biofilter with input concentrations of 0.18 – 1 g/m3 at empty bed residence times (EBRTs) of 30, 60, and 120 s was 10.06%, 21.45%, and 46.8%, respectively. When the photoreactor was used as a pretreatment system, the removal efficiency of the combined system in corresponding EBRTs was improved to 39.79%, 63.08%, and 92.60%, respectively. The results proved that the combined system provided higher removal efficiencies than the single biofilter. Thus, the application of the photoreactor as a pretreatment step was much effective in increasing the removal efficiency of n-hexane from the polluted air by the biofilter.

Chemical Composition and Bioactivity of the Essential Oil of Cassia singueana Flowers Growing in Nigeria

Cassia singueana (Delile) Lock from the family Fabaceae is a well-known medicinal plant that grows abundantly in Nigeria and other African countries, and has long been used in the treatment of various ailments including malaria and other infectious diseases. The present study aimed at assessing the composition, and bioactivity of the essential oil of the flowers of C. singueana collected from Nigeria. The essential oil was extracted by hydrodistillation and the chemical composition was analyzed by gas chromatography (GC) coupled with a flame ionization detector (GC-FID) and GC coupled to mass spectrometry (GC–MS). The bioactivity of the oil was determined using the brine shrimp lethality assay, agar diffusion antimicrobial test, the 2, 2-diphenylpicrylhydrazyl, metal chelation, and superoxide anion antioxidant assays. The essential oil yield and the percentage of identified compounds were 1.58% and 97.91%, respectively. More than 20 compounds were identified. The major component was geranyl acetone (36.82%) followed by phytol (18.12%). The essential oil showed lethality against the brine shrimp larvae with an LC50 value of 18.7 µg/ml, and antimicrobial activity with largest inhibition zones of 32-33 mm against Candida albicans, Streptococcus pneumoniae, and Staphylococcus aureus. The oil also exhibited considerable antioxidant activity as evident from its ability to scavenge free-radicals such as DPPH, superoxide anions, and metal-chelation.

Electrokinetic removal of radionuclides contained in scintillation liquids absorbed in soil type Phaeozem

Control samples of scintillation liquids – Phaeozem soil mixtures were prepared with different scintillation liquids as the support electrolyte, Install Gel® XF, (Ultima Gold AB™ and Ultima Gold XR™), to construct the polarization curves, and to select the cell potential with the highest mass transfer to remove 24Na (15 h) and 99mTc (6 h) as radiotracers from polluted Phaeozem soil. During the electrokinetic treatment (EKT), the removal of radionuclides contained in scintillation liquids absorbed in Phaeozem soil, liquid phase was characterized by Gas Chromatography coupled with a Flame Ionization Detector (GC-FID) and Fourier Transform Infrared Spectrometry (FTIR), solids by FTIR, before and after the application of cell potential. In this sense, the support electrolyte was selected based on the highest current generated (1 mA), as in the case of scintillation liquid 50% Ultima Gold XR™ + 50% Water (1:1), which was used for 6 h in the presence of a mesh and a titanium rod, as anode and cathode, respectively. Finally, the removal percentage accumulated in the liquid phase after the EKT of Phaeozem soil polluted by 99mTc was 61% close to the anode after 4 h. It was also 61% for 24Na close to cathode after 2 h, and after 4 h it was 71.8%.

Bio-Based Solvents for Green Extraction of Lipids from Oleaginous Yeast Biomass for Sustainable Aviation Biofuel.

Lipid-based oleaginous microorganisms are potential candidates and resources for the sustainable production of biofuels. This study was designed to evaluate the performance of several alternative bio-based solvents for extracting lipids from yeasts. We used experimental design and simulation with Hansen solubility simulations and the conductor-like screening model for realistic solvation (COSMO-RS) to simulate the solubilization of lipids in each of these solvents. Lipid extracts were analyzed by high performance thin-layer chromatography (HPTLC) to obtain the distribution of lipids classes and gas chromatography coupled with a flame ionization detector (GC/FID) to obtain fatty acid profiles. Our aim was to correlate simulation with experimentation for extraction and solvation of lipids with bio-based solvents in order to make a preliminary evaluation for the replacement of hexane to extract lipids from microorganisms. Differences between theory and practice were noted for several solvents, such as CPME, MeTHF and ethyl acetate, which appeared to be good candidates to replace hexane.

β-Cyclodextrin Based Molecularly Imprinted Solid Phase Extraction for Class Selective Extraction of Priority Phenols in Water Samples

Molecular imprinted polymer (MIP MAA-β-CD) with 2,4-dichlorophenol (2,4-DCP) and methacrylic acid functionalized β-cyclodextrin (MAA-β-CD) as the template molecule and the functional monomer, respectively, was prepared and used in molecular imprinted-solid phase extraction (MISPE) for the extraction of phenols (2,4-dichlorophenol, 2-chlorophenol, 4-chloro-3-methylphenol, 4-chlorophenol, 2,4,6-trichlorophenol, and 2-nitrophenol) from water samples. The MISPE method was optimized prior to the determination using gas chromatography coupled with a flame ionization detector (GC-FID). Under the optimized conditions, the MIP MAA-β-CD sorbent showed good linearity (0.01-12 mgL−1), low limits of detection (0.14-0.75 µgL−1), and good repeatability (RSD 2.3-3.6%, n = 3). Good recoveries were obtained in the range of 97-115% for tap water and between 88-103% for river water. The developed MIP MAA-β-CD SPE was then compared with other adsorbents. The unique properties of β-CD and presence of imprinted cavities explains the higher extraction recoveries obtained for phenols when using MIP MAA-β-CD SPE.

Study of Biodiesel Photodegradation Through Reactions Catalyzed by Fenton's Reagent

This study reports on the photodegradation of biodiesel in contact with water using the photo-Fenton reaction. After 360 h of photodegradation, we observed a reduction of 73% in the amount of fatty acid methyl esters (FAMEs) initially quantified by gas chromatography coupled with a flame ionization detector (GC/FID). During the photodegradation, peaks for ketones and epoxy groups in carbon chains were recorded by gas chromatography coupled with mass spectrometry (GC/MS), and typical aldehyde and short-chain fatty acid shifts in hydrogen nuclear magnetic resonance spectroscopy (1H NMR) were observed. Ecotoxicity assays with Artemia salina revealed the presence of toxic components in the aqueous phase in increasing amounts up to 168 h of photodegradation and decreasing thereafter.

Nutritional Profile of Phytococktail from Trans-Himalayan Plants

We estimated the nutritive value, vitamin content, amino acid composition, fatty acid content, and mineral profile of a phytococktail comprising sea buckthorn (Hippophae rhamnoides), apricot (Prunus armeniaca), and roseroot (Rhodiola imbricata) from trans-Himalaya. The free vitamin forms in the phytococktail were determined by rapid resolution liquid chromatography/tandem mass spectrometry (RRLC-MS/MS). Vitamin E and B-complex vitamins were detected as the principle vitamins. Reversed-phase high performance liquid chromatography (RP-HPLC) with pre-column derivatization was used for identification and quantification of amino acids. Eight essential and eleven non-essential amino acids were quantified, and the content ranged between 76.33 and 9485.67 µg/g. Among the essential amino acids, L-methionine, L-phenylalanine, L-lysine, L-leucine, and L-histidine were found to be the dominant contributors. We also quantified the fatty acids in the phytococktail by using gas chromatography coupled with a flame ionization detector (GC-FID) with fatty acid methyl esters (FAMEs) derivatization. The analysis revealed the presence of 4 major fatty acids contributing to the total lipid content. Palmitic acid was found to be the rich source of saturated fatty acid (SFA) and constituted ∼31% of the total lipid content. Among the unsaturated fatty acids (UFAs), palmitoleic acid (43.47%), oleic acid (20.89%), and linoleic acid (4.31%) were prominent. The mineral profiling was carried out by inductively coupled plasma optical emission spectrometer (ICP-OES), and it was found to contain a number of important dietary mineral elements. The harsh climatic conditions, difficult terrain, and logistic constraints at high altitude regions of Indian trans-Himalayan cold desert lead to the scarcity of fresh fruits and vegetables. Therefore, the source of multiple vitamins, essential amino acids, fatty acids, and dietary minerals from the phytococktail would provide great health benefit in the stressful environment and could be used as a high value nutritional supplement.

Seasonal and Altitudial Variation in Fatty Acid Composition of Native Bees

Fatty acids (Fas), the most important energy resources in insects, may change in structure and thus function with changing temperature, a hypothesis termed ‘homeoviscous adaptation’. We investigated whether the proportional composition of the most common fatty acids changes with seasonal (June to August) and altitudinal (2060 – 3290 m) variation in environmental temperature among four species of native bees. We identified the composition and proportion of each fatty acid using gas chromatography coupled with a flame ionization detector (GC-FID). Based on preliminary data, the most common fatty acids found in bees were palmitic acid (C 16:0), stearic acid (C 18:0), oleic acid (C 18:1), linoleic acid (C 18:2) and linolenic acid (C 18:3), with other fatty acids including myristic acid (C 14:0) and palmitoleic acid (C 16:1) also present in small amounts. We are currently 23eticulat GC data for larger bees and establishing protocols for fatty acid composition analysis of small tissue samples. Based on the seasonal and altitudinal variation in ambient temperature, we expect to see variation in fatty acid proportions in bees from different months at both sites.