Gas Chromatography With Flame Ionization Detection Research Articles

Rapid analysis of eucalyptus oil adulteration in Moroccan rosemary essential oil via GC-FID and mid-infrared spectroscopy

Essential Oil (EO) extracted from Rosemary is known for its therapeutic, antifungal, stimulant and antibacterial effects. This study aimed to detect and quantify the adulteration of Rosemary essential oil with different percentages of eucalyptus essential oil, using two analytical techniques: gas chromatography with Flame Ionization Detection (GC-FID) and Fourier Transform Mid-infrared spectroscopy (FT-MIR), combined with chemometric tools such as Principal Component Analysis (PCA), Partial Least Squares regression (PLS-R) and support vector regression (SVR). The use of PCA on the results obtained from GC-FID and FT-MIR indicates the possibility of categorizing the data into two distinct groups: adulterated essential oil and non-adulterated essential oil. However, it is noted that GC-FID can only detect adulteration starting from 40%, while spectroscopy is capable of detecting lower percentages of adulteration. The use of PLS-R and SVR calibration models for adulteration quantification demonstrates high performance capabilities for both techniques (GC-FID and FT-MIR), as indicated by high R2 correlation coefficients indicating good fit, with lower root mean square error (RMSE) values demonstrating predictive accuracy. The results suggest that FT-MIR spectroscopy is preferable to GC-FID for the quantification and discrimination of adulterated essential oils. FT-MIR spectroscopy is considered superior to GC-FID due to its non-destructiveness, speed and lack of sample preparation.

From inspection to analysis: A combined approach to identifying counterfeit whiskeys using HS-GC-FID and bottle integrity

Counterfeiting of alcoholic beverages, particularly high-value spirits such as whiskey, presents significant challenges for regulators, manufacturers, and consumers. In this study, we introduce and validate a novel application of headspace extraction (HS) followed by gas chromatography with flame ionization detection (GC-FID) for the quantitative determination of ethanol content in 42 suspected counterfeit brazilian samples of whiskeys. This method, in conjunction with visual inspection of material inconsistencies, offers a combined approach to identify potential cases of fraud. The HS-GC-FID findings revealed that only 19% of the analyzed samples had ethanol content in the limits declared on the label, emphasizing the role of ethanol content as a chemical marker for suspected beverage fraud.

Oxidative Liquefaction, an Approach for Complex Plastic Waste Stream Conversion into Valuable Oxygenated Chemicals

Various waste streams including municipal solid waste (MSW), polymer waste from personal protective equipment (PPE) used in medical fields, and composite waste from wind turbine blades (WTBs) demand modern waste management and recycling approaches. Ultimate and proximate analysis of mentioned samples revealed a higher content of carbon—28.2 ± 8.0, 80.1 ± 2.3, and 50.3 ± 2.3, respectively—exhibiting sufficient potential to be converted into secondary carbon-based compounds. For this purpose, oxidative liquefaction of selected waste materials was carried out following a detailed experimental plan, a centred composite design for WTBs, and a central composite face-centred plan for MSW and PPEs. Temperature, pressure, oxidant concentration, reaction time, and waste-to-liquid ratio were the parameters of key interest, and their values were tested at a range of 200–350 °C, 20–40 bar, 15–60%, 30–90 min, and 3–25%, respectively, depending upon the type of waste. As a result, total polymer degradation (TPD) was recorded for three types of waste and the results were satisfactory, encouraging the decomposition of primary waste in liquid oxygenated chemical compounds (OCCs). Gas Chromatography with Flame Ionisation Detection (GC-FID) helped us quantify the number of OCCs for each waste sample. Energy consumption during the process was also recorded and optimisation of the experimental plan based on maximum TPD and OCCs yields against the minimum energy consumption was performed to make the process tech-economic.

Gravimetric Preparation of Toluene CGMs in Nitrogen Gas: Verification and Stability Assessment

AbstractThis research paper presents the preparation, verification and stability evaluation of a toluene calibration gas mixtures (CGMs) in nitrogen gas via gravimetric method. These toluene gas mixtures are prepared gravimetrically i. e., by wt. mixing of high‐purity gases according to the International Organization for Standardization, ISO 6142, and are validated as per ISO 6143. Toluene gas mixtures within the range of 5 to 20 μmol/mol are prepared and traceability with SI, ‘International system of units’, amount of substance, the ′mole′, through mass‐based measurements is achieved. The verification of prepared CGMs was carried out using a GC‐FID (gas chromatography with flame ionization detector) technique, and the outcomes demonstrated a consistent linear correlation between instrumental response and gravimetric amount fraction for all gas mixtures, which confirmed the accuracy and reliability of CGMs. The gravimetric uncertainty of the prepared gas mixtures, as projected in terms of amount fractions, is below 1 % relative, while the analytical uncertainty is in the range of 2–3 % relative at a confidence level of k=1. The stability study investigation over a period of one year demonstrated that the mole fraction of toluene remained consistent throughout the entire duration, which indicated the long‐term stability of the CGMs.

Synthesis of Bio-based Polyol Via Epoxidation and Hydroxylation of Shea Butter Fats

Polyols are mostly made from petroleum and other non-biodegradable fossil fuels, and as such, they are not environmentally benign. This study presents the process of making bio-based polyols from shea butter fats (SBF) by epoxidation and hydroxylation. Wet analysis, gas chromatography with flame-ionization detection (GC-FID), and Fourier transform infrared spectroscopy (FTIR) were all used to characterize the bio-based polyols. The acid number (13.92 mg KOH/g), iodine value (19.54 mg I2/100 g), saponification value (218.03 mg KOH/g), and viscosity (107.98 poise) suggest a good quality of synthesized SBF-polyol. The FTIR analysis of SBF-polyol indicates the existence of specific vibrational frequencies: 3473 cm-1 for hydroxyl (OH) groups, 2921–2854 cm-1, and 2929–2858 cm-1 for carbon-hydrogen (C-H) and methylene (CH2) groups, respectively, and 1748 cm-1 for carbonyl (-C=O) groups. The major unsaturated fatty acids detected in SBF were oleic acid, with an estimation of 10.41%; linoleic acid and linolenic acid were reported at 0.34% and 1.67%, respectively; however, they were absent in SBF-polyol. According to this data, bio-based polyols can be synthesized using SBF and are suggested for the production of top-notch polyols.

OPTIMIZATION AND VALIDATION OF LIQUID-LIQUID EXTRACTION (LLE) METHOD AND THE APPLICATION OF GAS CHROMATOGRAPHY WITH FID DETECTOR FOR THE DETERMINATION AND QUANTIFICATION OF VOLATILE FATTY ACIDS IN EFFLUENTS FROM ANAEROBIC REACTORS

Controlling the chemical parameters of the anaerobic digestion (AD) process is essential for the bioconversion of organic matter to methane; among these parameters include the presence and concentration of volatile fatty acids (VFAs). It is thus necessary to use efficient analytical methods that are capable of identifying and quantifying VFAs in reactor effluents in order to obtain an immediate response to their conditions. In this study, the liquid-liquid extraction (LLE) method was optimized and validated − through an adaptation of the official method, using acetone and KHSO4, and gas chromatography with flame ionization detector (GC-FID) was used for the determination of acetic, propionic, isobutyric, butyric, isovaleric and valeric acids present in the effluents. The limit of detection (LOD) and limit of quantification (LOQ) obtained were 1.2-2.5 mg L-1 and 1.9-3.7 mg L-1, respectively, for all analytes. These low LODs and LOQs are essentially important because the presence of isobutyric and isovaleric acids above 5.0 mg can be considered indicative of imbalances in AD. The proposed method, which presented satisfactory results with good repeatability (4.2-20.7%) and recovery (90.9-104.0%) rates, was applied for the analysis of effluent samples from three continuous stirred-tank reactors (CSTR).

Converting neem seed-derived oil into biodiesel using zeolite ZSM-5 as an efficient catalyst via electrosynthesis procedure: Optimization of operating variables using response surface methodology (RSM)

Biodiesel has been contemplated as the best alternative to diesel fuel, owing to its distinctive qualities which cause environmental preservation. The purpose of this research is to convert Neem Seed-Derived Oil (NSDO) into biodiesel through zeolite ZSM-5 as a heterogeneous acid catalyst, by applying an electrosynthesis technique. The response surface methodology according to central composite design (RSM-CCD) was exerted to optimize the process conditions and obtain a reliable model. Based on the RSM-CCD technique, the parametric range for optimization study was as follows: voltage of 10–40 V, time of 0.5–1.5 h, Me/NSDO of 10–30 molar ratio, and catalyst amount of 2–6 wt%. The best yield of produced biodiesel, based on the design of the experiment's model predictions, was 85.96%, and based on the experimental observations, was obtained at 86.03%, which indicates a very high adaptation of experimental design with experimental data. The optimal operating conditions, to get the best process efficiency, were as follows: voltage of 25 V, time of 1 h, Me/NSDO (Methanol to Neem Seed Derived Oil) molar ratio of 20:1, and catalyst amount of 6 wt%. The reaction yielded satisfactory results due to the catalyst's exceptional efficiency, which also demonstrated impressive performance and reusability, exhibiting only a 14% reduction in yield after five successive cycles. The catalyst was characterized by analyses, and moreover the produced biodiesel was analyzed by qualitative and quantitative analyses of FT-IR (Fourier Transform Infrared Spectroscopy) and GC-FID (Gas Chromatography with Flame Ionization Detector). As well as, to investigate the produced biodiesel quality, physicochemical analyzes were used, according to ASTM (American Society for Testing and Materials) standards, and the measured results were completely consistent with the quality characteristics of diesel fuel.

Pilot Study of 3D Spatial Distribution of α-Pinene Emitted by Norway Spruce (L.) Karst Recently Infested by Ips typographus (L. 1758) (Coleoptera: Scolytinae)

The Eurasian Spruce Bark Beetle (Ips typographus) (L. 1758) (Coleoptera: Scolytinae) poses a significant threat to Eurasia’s Norway spruce (Picea abies) (L.) Karst, forests. Early detection of infested trees is crucial to control beetle outbreaks and allow salvage logging before the next generation emerges. Besides traditional methods, new approaches focus on monitoring volatile organic compounds, mainly monoterpenes, emitted by infested trees. Using analytical chemistry, we studied the distribution of these compounds, particularly α-pinene, around infested trees. In lab trials, we optimized α-pinene detection using dynamic absorption and solid-phase microextraction (SPME), analyzed by gas chromatography with flame ionization detection (GC-FID). We conducted forest trials, revealing varying α-pinene abundance due to changing conditions. However, consistent trends emerged: levels were highest near the infested tree stem and 1.3 m above ground in the first trial and at a 1 m distance from the infested stem in the second. We generated a three-dimensional cloud depicting the distribution of α-pinene around infested trees in their natural habitat. These findings open avenues for detecting bark beetles on a large scale by mapping elevated concentrations of volatile organic compounds emitted by infested trees, potentially leading to alternative pest management methods. Scanning methods, such as electronic sensors combined with remote sensing, hold promise for this application.

A simple laboratory method for the generation of mixed brominated-chlorinated paraffin single chain mixtures

Brominated-chlorinated paraffins (Br-CPs) are a comparably new compound class that features both Cl and Br atoms on one or several alkane backbones. Due to legal restrictions in the use of conventional chlorinated paraffins (CPs), Br-CPs have the potential to become emerging contaminants. Currently, their determination is hampered by the lack of suitable reference standards. Here, we present a simple synthesis procedure with single chain alkanes that leads to Br-CPs with ∼4–8 chlorine and 1 to 4 bromine substituents according to gas chromatography with electron capture negative ion mass spectrometry (GC/ECNI-MS). The single-chain Br-CP mixtures were obtained by the shared chlorination and bromination of eight single-chain alkanes (C10 to C17) at two reaction times, respectively. The carbon content of the 16 single-chain Br-CP products, determined by elemental analysis (EA), ranged from 30.8 to 43.8 %. The typical hump peak known from CPs was detected with GC with flame ionization detection (GC/FID), electron capture detection (GC/ECD) and GC/ECNI-MS. The complexity indicated that low-resolution mass spectrometry is not sufficient for an adequate analysis of Br-CPs. A mathematical formula was developed which allows to calculate all possible combinations of Br and Cl that are in line with the carbon content. The proton magnetic resonance spectroscopy (1H NMR) spectra showed similarities to the ones of CPs with one chemical shift range for protons on nonhalogenated carbons and one for protons with one halogen on the same carbon.

Multi-block analysis of the oxidative stability of the palm olein and hydrogenated soybean oil during the industrial deep-frying process

The partially hydrogenated soybean oil and palm olein used in the industrial frying process were analyzed through physicochemical parameters, mid-infrared spectroscopic with attenuated reflectance (FTIR-ATR), fatty acid profile (FAP) and iodine value by gas chromatography with flame ionization detector (GC-FID), and volatile organic compounds (VOC) formation by solid-phase microextraction (SPME) in static headspace and GC-FID. The common dimension analysis (ComDim), a mid-level data fusion approach, was used to allow the multi-block exploratory data analysis of the fats. There were significant differences (p > 0.05) in acid value, peroxide value, p-anisidine value, total oxidation (Totox), and extinction coefficient at 232 nm and 270 nm between the fats before frying (T1) and after frying cycles. The percentage of (2E,4E)-Deca-2,4-dienal for organic volatile compounds was reduced, while acrolein increased. Oleic acid was predominant in both fat samples. Differences in absorption bands in the FTIR-ATR spectra enabled the distinction between partially hydrogenated soybean oil and palm olein.

Effect of consumption of sheep and cow milk on rat brain fatty acid and phospholipid composition

The effect of sheep milk and cow milk on the lipid composition of rat brain was investigated in two feeding experiments of 28-days duration. Total lipids of the rat brain were extracted using ethanol-hexane, and the fatty acids and phospholipid contents analysed using gas chromatography with flame ionization detection (GC-FID) and phosphorus-31 nuclear magnetic resonance (31P NMR). Furthermore, freeze-dried pooled samples were analysed using attenuated total reflectance Fourier Transform Infrared and Fourier Transform Raman Spectroscopy and analysed with multivariate methods. A significantly (P < 0.05) higher C18:2 content was found in the cow milk group compared with sheep milk-treated groups in Study one. In Study two, a significantly (P < 0.05) lower C16:0 content was present in the sheep milk-treated group compared to the control low Ca/P group. No significant (P > 0.05) differences were observed in the spectroscopy analyses. It is concluded that sheep and cow milks fed to rats for 28-days had a low effect on the brain lipidome.

Targeting H3N2 influenza virus RNA dependent RNA polymerase dependent inhibitory activity by principal components from latex of Calotropis gigantean

The H3N2 influenza virus is spiking dramatically, which is a major concern worldwide and in India. The multifunctional hetero-trimer influenza virus RNA-dependent RNA polymerase (RdRP) is involved in the generation of viral mRNA and is crucial for viral infectivity, which is directly related to the virus’s ability to survive. The goal of the current work was to use molecular docking to determine how the RdRP protein might be affected by powerful bioactive chemicals found in Calotropis gigantia latex. By applying CB-dock 2 analysis and 2D interactions, an in-silico docking study was conducted using a GC-FID (gas chromatography with flame-ionization detection) based composition profile. Tocospiro A (15%), Amyrin (7%), and Gombasterol A were found by GC-FID to be the main phytocompounds in the latex of Calotropis gigantia. The docking result showed that ligands were effectively bound to RdRP. According to interaction studies, RdRP/ligand complexes create hydrogen bonds, van der Waals forces, pi-alkyl bonds, alkyl bonds, and pi-Sigma bonds. Therefore, it was suggested that Calotropis gigantia latex may represent a possible herbal remedy to attenuate H3N2 infections based on the above findings of the fragrance profile and docking.

Polyphenols, Flavonoids, Mineral Elements, and Biological Activities of Ginger and Cinnamon Essential Oil and Extracts as Regulated by Their Isolation Procedures

Our research compared the chemical make-up of wild Ginger and cinnamon, including their essential oils (EOs), total phenol, and total flavonoid, for their antioxidant and antibacterial effects in vitro. The mineral (nutritional and poisonous) components of the plant were also identified in this investigation. Hydro distillation (HD), steam distillation (SD), and microwave-assisted distillation (MAD) were used to extract the EOs, and gas chromatography with flame ionization detection (GC-FID) and mass spectrometry detection (GC-MS) were used to examine them. 2,2-diphenyl-1-picrylhydrazyl (DPPH) was used to evaluate the EOs' antioxidant properties. The essential oil was analyzed, and twenty-six components were found to make up 97.73% of the oil with a yield of 0.202%. The primary components were pulegone (74.81%), menthone (13.01%) and piperitone (3.82%). Neutron activation analysis (INAA) and inductively coupled plasma optical emission spectrometry (ICP-OES) were used to detect twenty-one elements, including macro- and micro-elements (Ba, Br, Ca, Cl, Co, Cr, Cs, Eu, Fe, K, Mg, Mn, Mo, Na, Rb, Sb, Sc, Sr, Th, U, and Zn), with the mineral element concentration being very close to the FAO recommendation.

Chemical characteristics and biological activity screening of Pistacia lentiscus mastic gum and leaves from Türkiye.

Mastic gum is a resin that is produced by Pistacia lentiscus. It has many traditional uses, dating from ancient times, such as the treatment of gastrointestinal disorders and as a food additive. In this study, the leaves and mastic gum of trees of different ages from Karaburun and the Cesme peninsula in Türkiye were examined chemically and biologically. Flavonoids, and phenolic and fatty acid components were evaluated by a liquid chromatography system coupled with high resolution mass spectrometry (LC-HRMS) and gas chromatography with flame ionization detection (GC-FID). Cytotoxicity was screened against several cancer and healthy cell lines using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Inducible nitric oxide synthase (iNOS) inhibition was determined on lipopolysaccharide (LPS)-induced murine macrophage cell line(RAW264.7) cells. Antiviral activity was measured against avian coronavirus using an in ovo virucidal antiviral activity assay. The main phenolic constituents of the gum were found to be salicylic, rosmarinic, and caffeic acids whereas the most abundant compounds detected were flavonoids in the leaf extracts. The most abundant fatty acids in hexane extracts were palmitic and oleic acids. All gum extracts except 3-year-old gum had significant cytotoxic activity on HeLa (IC50 1.74 ± 0.03-4.76 ± 0.95) and PC-3 (0.64 ± 0.25-6.22 ± 1.40) cells. Moreover, reducing virus activity by fivefold or sixfold logarithmically between the range of 5-10 μg g-1 of 30-year-old gum extracts underscored the biological activity. In ovo antiviral activity studies on the P. lentiscus were conducted for the first time. The mastic gum and leaves obtained from P. lentiscus may have strong potential in terms of their chemical content and antiviral and cytotoxic activity. As a consequence of these properties, it is a sustainable, renewable natural resource that can be used as an additive and flavoring in the food and pharmaceutical industries. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Simultaneous Determination of General Active Ingredients in Topical Formulations by Gas Chromatography with Flame Ionization Detection (GC-FID)

Abstract A simple, fast, precision and sensitive gas chromatographic method was developed for determination of camphor, L-menthol, methyl salicylate, salicylic acid, benzyl nicotinate and nonivamide in topical formulations. The possibility of determination low-boiling components and high-boiling components by a single analytical method was shown. The method was optimized by evaluating the effect of a large number of chromatographic parameters and sample preparation stages. It was validated according to the International Council on Harmonization guidelines. Limit of quantification of active components were achieved from 0.7 μg/mL for benzyl nicotinate and L-menthol to 41 μg/mL for salicylic acid. High repeatability and good recovery values were demonstrated. The practical application of the proposed method was shown for ointments and cream.

Fast and reliable characterization of egg triacylglycerol profiles using atmospheric solids analysis probe tandem mass spectrometry (ASAP-MS/MS) combined with chemometric tools

In this study, the potential of atmospheric solid analysis probe tandem mass spectrometry (ASAP-MS/MS) was assessed as a green and rapid method combined with gas chromatography with flame ionization detection (GC-FID) and chemometrics to determine the triacylglycerol (TAG) profile of eggs from various housing systems, including indoor, cage-free, free-range, organic, and enriched systems. The most abundant ions were identified using the product ion and neutral loss scan. The fatty acid composition, mainly unsaturated, palmitic, and stearic acids of eggs was influenced by the housing systems. The optimal conditions of ASAP-MS for cone voltage, desolvation gas temperature, and desolvation gas flow were determined to be 40 V, 600 °C, and 1100 L h−1, respectively. The main TAGs (50:2, 50:1, 52:4, 52:3, 52:2, 52:1, 54:4, 54:3, 54:2, 54:1) were observed in the mass range m/z 830–890. Notable differences were observed for TAGs 54:1 and 52:4, which were found in significantly higher levels on WE and CE. The proposed methodology enables rapid and efficient TAG profiling of egg yolks, providing a solid foundation for future research in this field.

Simultaneous quantification of six flavouring agents in herbal freshness gel toothpaste by gas chromatography

AbstractThere are many methods reported to identify and quantify volatile compounds. Many of them are based on chromatographic techniques, such as high‐performance liquid chromatography (HPLC), gas chromatography with flame ionization detector (GC‐FID), and GC coupled with mass spectrometry (GC–MS). But among all GC‐FID and GC–MS are majorly used for the detection and quantification of volatile compounds. A new gas chromatographic method has been developed for simultaneous determination of six flavouring agents [menthol, benzyl alcohol, methyl salicylate, anethole, menthol carboxamide (WS‐3) and eugenol] in herbal freshness gel toothpaste. All six flavours were separated using a DB‐WAX (Agilent) capillary GC column (30 m × 0.25 mm × 0.25 μm) and flame ionization detector (FID). This method was validated for various parameters such as precision, linearity, accuracy, stability, robustness, limit of detection, and limit of quantification as per ICH guidelines, AOAC internationals Appendix K. All the validation parameters were found to be within acceptable limits. The method was successfully applied for the quantification of all flavouring agents in toothpaste formulations.

An Improved Validated Method for the Determination of Short-Chain Fatty Acids in Human Fecal Samples by Gas Chromatography with Flame Ionization Detection (GC-FID).

Short-chain fatty acids (SCFAs) are metabolites produced by the gut microbiota through the fermentation of non-digestible carbohydrates. Recent studies suggest that the gut microbiota composition, diet and metabolic status play an important role in the production of SCFAs. The primary objective of this study was to develop a simplified method for SCFA analysis in human fecal samples by gas chromatography with flame ionization detection (GC-FID). The secondary objective was to apply the method to fecal samples collected from a clinical trial. The developed GC-FID method showed excellent linearity (R2 > 0.99994), with a limit of detection (LOD) ranging from 0.02 to 0.23 µg/mL and a limit of quantification (LOQ) ranging from 0.08 to 0.78 µg/mL. Recovery for the method ranged between 54.24 ± 1.17% and 140.94 ± 2.10%. Intra- and inter-day repeatability ranged from 0.56 to 1.03 and from 0.10 to 4.76% RSD, respectively. Nine SCFAs were identified and quantified (acetic, propionic, iso-butyric, butyric, iso-valeric, valeric, 4-methyl valeric, hexanoic and heptanoic acids) in freeze-dried fecal samples. The clinical trial compared participants with prediabetes mellitus and insulin resistance (IR-group, n = 20) to metabolically healthy participants (reference group, R-group, n = 9) following a 4-week intervention of a daily red raspberry smoothie (RRB, 1 cup fresh-weight equivalent) with or without fructo-oligosaccharide (RRB + FOS, 1 cup RRB + 8 g FOS). The statistical analysis (Student's t-test, ANCOVA) was performed on PC-SAS 9.4 (SAS Institute). Acetic acid was higher in the R-group compared to the IR-group at baseline/week 0 (p = 0.14). No significant changes in fecal SCFA content were observed after 4 weeks of either RRB or RRB + FOS.

Three-dimensional rose-like zinc oxide fiber coating for simultaneous extraction of polychlorinated biphenyls and polycyclic aromatic hydrocarbons by headspace solid phase microextraction

The three-dimensional (3D) rose-like zinc oxide (ZnO) material was prepared by a simple one-step CTAB-assisted hydrothermal strategy and used as a headspace solid-phase microextraction (HS-SPME) coating. Polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) were analyzed by gas chromatography with flame ionization detector (GC-FID), and conclusively applied to ultrasensitive detection in lake and river water. Compared with one-dimensional (1D) pencil-like ZnO, the layer-by-layer petal-like structure could fully expose mass adsorption sites on the surface, which could significantly improve the adsorption. The enrichment factors with 7535–8595 for PCBs and 3855–7320 for PAHs were achieved. The established method provided a satisfactory linear range (0.005–30 ng·mL−1), coefficient (R2 > 0.9978), ultra-low limit detection (1–3 pg·mL−1), and long service life (≥ 150 times). The recoveries of 83.42–120.86 % were obtained in the real detection application of lake and river water. This work demonstrated that 3D rose-like ZnO with low cost, simple synthesis, fast extraction ability and high enrichment performance was an ideal coating material, which was hoped to enrich other compounds with similar structures with PCBs and PAHs.

Targeting H3N2 Influenza Virus RNA-dependent RNA Polymerase by Using Bioactives from Essential Oils from Eucalyptus polybrachtea, Cymbopogon citratus and Cymbopogon khasianus

A dramatic surge of H3N2 influenza virus is of grave concern worldwide and particularly in India. H3N2 cause acute respiratory infection, however, a few drugs are available for its mitigation. Subsequently, researchers have been involved in efforts to discover novel antiviral mechanisms that can lay the basis for new anti-influenza drugs. Influenza virus RNA-dependent RNA polymerase (RdRP) is a multi-functional hetero-trimer, implicated in the production of viral mRNA, hence plays a major role in viral infectivity thus directly associated with survival of the virus. RdRP have been cited as anappropriate target for therapeutic drug design. In the present study molecular docking was designed to estimate the effect of potent bioactive moleculesfrom essential oils from Eucalyptus polybrachtea (eucalyptus oil, EO), Cymbopogon citratus (lemon grass essential oil, LEO) and Cymbopogon khasianus (palmarosa essential oil, PEO) against RdRP protein. GC-FID (gas chromatography with flame-ionization detection) based composition profile, and in-silico docking study was conducted by using CB-dock 2 analysis followed by 2D interactions. GC-FID revealed eucalyptol, geranial and geraniolas major phytocompounds in EO, LEO and PEO respectively. The docking score indicated effective binding of ligands to RdRP. Interactions results indicated that, RdRP/ligand complexes form hydrogen, van der waals forces, pi-alkyl, alkyl, and pi-Sigma interactions. Based on above findings of aroma profile and docking, therefore, it was recommended that essential oils from above mentioned aromatic cropsmay represent potential herbal treatment to mitigate H3N2 infections.