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129Xe NMR spectroscopy of polymers can provide important information on void spaces, sometimes called free volume, in polymers. Unfortunately, the spectroscopy's low sensitivity has limited its widespread use in both academic and industrial research. In order to overcome such a difficult situation, hyper-CEST method which employs hyperpolarization and CEST techniques, is examined after the introduction of recirculation and subtraction modes. Alongside the incorporated stopped-flow technique, these modes were very efficient in detecting very weak hidden signals from cellulose nanofiber (CNF) and silk fibroin (SF) films and in discussing the void space in these polymers. From the analysis of detailed saturation frequency dependence in the increment of 100 Hz, the chemical shifts of hidden peaks were successfully determined to give reasonable values for the size of void space in CNF and SF. Application on thermoplastic polyurethane film also supported our method of analysis. The subtraction mode was very efficient in judging the presence or absence of any peak at a fixed saturation frequency. These facts support that the mode will surely be useful in the future exploratory study of very weak hidden signals.

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Determination of olefins in pyrolysis oils from waste plastics and tires is crucial for optimizing the pyrolysis process and especially for the further advanced valorization of these oils in terms of the circular economy. Identifying olefins, even using high-resolution techniques like GC×GC, is challenging without TOF-MS, which allows modification of the ionization step. Currently, the only method for determining olefins in plastic pyrolysis oils is GC-VUV, recently standardized as ASTM D8519. However, TOF-MS and VUV are not affordable instruments for many research teams working on plastics recycling. This paper introduces a simple method for the selective micro-scale adsorption of olefins over AgNO3/SiO2, followed by the GC×GC-FID analysis. Olefins are determined indirectly from the loss of chromatographic area in respective hydrocarbon groups before and after removal. Only 50 µL sample and 15 min of sample separation are needed. Our method was extensively validated and provides a reliable determination of olefin content in a wide range of pyrolysis oils from plastics and tires and their products after mild hydrotreatment. It is affordable to all researchers and industrial companies working on plastics recycling by thermochemical processes as it does not require an MS detector.

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The unclear mechanisms of ethanol metabolism in the brain highlight the need for a deeper understanding of its metabolic pathways. This study used in vivo microdialysis to simultaneously sample ethanol and its metabolites, acetaldehyde and acetate, in the rat striatum following self-administration of ethanol, emphasizing the natural oral exposure route. To enhance the self-administration, rats underwent two-bottle-choice and limited access training. Dialysate samples, collected every 10 minutes for 2.5 hours, were analyzed using gas chromatography with flame ionization detection (GC-FID). The measured time courses of dialysate concentrations of ethanol, acetaldehyde, and acetate provided insights into dynamics of ethanol metabolism. Notably, in a subject with low ethanol consumption (0.29 g/kg), the concentration of acetaldehyde remained below the limit of detection throughout the experiment. However, the acetate concentration was clearly increased after ethanol consumption in this subject and was comparable to that of other rats with higher ethanol consumption. Compared with focusing only on peak values in the time-courses of concentrations of ethanol and its metabolites, calculating areas under curves provided better models of the relationships between ethanol intake and individual ethanol metabolites, as indicated by the r-square values for the linear regressions. This approach of using the area under the curve accounts for both the amplitude and duration of the concentration profiles, reducing the impact of variations in individual drinking patterns. In vivo microdialysis enables concurrent sampling of brain metabolites during oral ethanol administration, contributing insights into metabolite dynamics. To our knowledge, this paper is the first to report measurement of all three analytes in the brain following self-administration of ethanol. Future studies will explore regional variations and dynamics post-ethanol dependence, further advancing our understanding of ethanol metabolism in the brain.

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In this study, amino-modified micro-mesoporous silica (NH2-MMS) with hierarchical pores was prepared by modifying micro-mesoporous silica ZSM-5 with 3-aminopropyltriethoxysilane and used as an adsorbent in solid-phase extraction to analyze free fatty acids (FFAs) in krill oil during storage for an initial time. The Brunner Emmet Teller adsorption experiment and Fourier transform infrared spectroscopy demonstrate that NH2-MMS, with a hierarchical pore structure, was successfully synthesized. The adsorption experiments, especially static adsorption, indicate that the absorption ability of the prepared NH2-MMS, with a hierarchical pore structure, toward FFAs was better than that of traditional amino-modified mesoporous silica (SBA-15) with a mesoporous structure at all temperature and concentrations. Fairly low limits of detection (0.06-0.15 µg g-1), acceptable recoveries (85.16-94.31%), and precision (0.08-5.26%) were attained under ideal circumstances. Moreover, NH2-MMS has the advantages of easy preparation and being environmentally friendly. As a result, this method offers an alternative to the current method for determining FFAs in different kinds of oil specimens.

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Because of their major role in indoor and outdoor air pollution, even at trace levels, VOCs are of great interest, and their monitoring requires sensitive analytical instruments. Several techniques are commonly used, such as portable sensors, Proton Transfer Reaction Mass Spectrometry (PTR-MS) and Thermal Desorption Gas Chromatography (TD-GC). The latter is widely used off- and on-line with Flame Ionization Detectors (FID) or Mass Spectrometers (MS). Given the large number of molecules detected per chromatogram, the data generated by these monitoring techniques are usually checked and reprocessed manually. This process is extremely time consuming and could result in human error. The challenge is to provide reliable results as quickly as possible. In this study, the performances of an on-line TD-GC system with dual detection FID and MS were tested. The Method Detection Limits (MDL), linearities and accuracies of 60 VOCs (alkanes, aromatics, oxygenated and halogenated) were calculated both for FID and MS detectors. The MDLs and accuracies ranged from 0.006 to 0.618 ppbv and from 77 % to 100 % for FID, and from 0.018 to 0.760 ppbv and from 80 % to 100 % for MS. Both detectors showed good complementarity and allowed the development of two programs to facilitate data analysis. These algorithms were designed to autonomously select optimal results between FID and MS detectors, and were evaluated for outdoor and indoor measurement conditions. Measuring VOCs in field campaigns is challenging, and it is anticipated that these programs could be extended to other types of dual-detector systems or for the comparison of data from different calibrated instruments.

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Diversion of oil sources for biodiesel production has been gaining importance to meet the environmental concerns and energy demand. The free fatty acid (FFA) content of the feedstock is a significant factor in biodiesel production. The FFA values determine the complexity of the biodiesel production. Until date, an experimental procedure has been used to determine the FFA concentration of an oil source; this method is dependent on titration, which is a laborious process involving significant volumes of chemicals. Hence, in the present study, an attempt was made to develop a device for the identification of FFA of the oils. Waste cooking oil samples subjected to wide range of cooking conditions like cooking time, temperature, type of food are collected from different food outlets. Subsequently, the composition of oil samples and the variation in their quality were analysed using gas chromatography flame ionization detector (GC - FID). Biodiesel is prepared from the oil samples through transesterification and the impact of FFA and their respective methyl esters in the quality and properties have been investigated. The properties of biodiesel were determined as per ASTM standards. The study was further extended to correlate the properties of biodiesel with the composition of the oil from which it was derived. The analysis evidently proved the dependence of biodiesel properties on the FFA percentage and the composition of the oil. The results have been further substantiated with the performance and emission characteristics of internal combustion engine fuelled with the prepared biodiesel samples.

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We report on a deep-red emissive fluorogenic peptide probe for human immunodeficiency virus-1 (HIV-1) trans-activation responsive (TAR) RNA as an indicator for fluorescence indicator displacement (FID) assay. The probe design is based on the concept of the forced intercalation of thiazole orange (TO) dyes (FIT) on the peptide backbone, as recently proposed by our group, where the Q (glutamic acid) residue in the Tat peptide (RKKRR-Q-RRR) is replaced with TO as if it were an amino acid surrogate. Here, instead of green emissive TO, we utilized a deep-red emissive benzo[c,d]indole-quinoline (BIQ) cyanine dye developed previously by our group for imaging of nucleolar RNA in living cells. The developed 9-mer FIT peptide (RKKRR-BIQ-RRR; named BIQ-FiLuP) exhibits a significant off-on signaling ability for TAR RNA (λem = 660 nm, I/I0 = 130-fold, Φfree = 0.0009, Φbound = 0.052), and the dissociation constant Kd reaches ca. 1 nM. When used in FID assay, BIQ-FiLuP, like TO-based FiLuP, is able to distinguish between competitive and noncompetitive inhibitors, which has never been demonstrated with all previous indicators for TAR RNA. Deep-red emissive BIQ-FiLuP facilitates the evaluation of green to yellow emissive ligands without suffering from optical interference. The combination use with green emissive TO-based FiLuP (λem = 541 nm) would cover the examination of a wide range of fluorescent test compounds.

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An ultrasound-assisted dispersive liquid-liquid microextraction by solidifying floating organic droplets, coupled to a form of temperature-programmed gas chromatography flame ionization detection, has been developed for the extraction and determination of thymol and carvacrol. This method utilizes undecanol as the extraction solvent, offering advantages such as facilitating phase transfer through solidification and enhancing solvent-focusing efficiency. The optimal gas chromatography conditions include a sample injection volume of 0.2 µL, a split ratio of 1:10, and a flow rate of 0.7 mL min-1. The extraction conditions entail an extraction solvent volume of 20 µL, a disperser solvent (acetone) volume of 500 µL, pH 7.0, 7.0% NaCl (3.5 M), a sample volume of 5.0 mL, an ultrasound duration of 10 min, and a centrifuge time of 7.5 min (800 rpm). These conditions enable the achievement of a high and reasonable linear range of 3.5 to 70. 0 µg mL-1 for both thymol and carvacrol. The detection limits are found to be 0.95 and 0.89 µg mL-1, respectively, for thymol and carvacrol. The obtained relative standard deviations, 2.7% for thymol and 2.6% for carvacrol, demonstrate acceptable precision for the purpose of quantitative analysis.

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Vitis vinifera L. is a natural source of bioactive compounds that is already used for cosmeceutical and nutraceutical approaches. However, their phytochemical and antioxidant properties, although studied, have not been fully explored. We aimed to characterize V. vinifera L. cv. Falanghina seed extracts in different polarity solvents (hexane, ethyl acetate, ethanol, and a mixture of acetone-water) for their phytochemical contents, including the total phenolic compound content (TPC), free radical scavenging capacities, and antioxidant ability on HepG2 cells. We directly profiled the functional quality of V. vinifera seed extracts against H2O2-induced oxidative stress in HepG2 cells, focusing on mitochondrial functions. The content of bioactive compounds was characterized by LC-MS. To assess the cytocompatibility of the extracts, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was conducted. Results showed that extraction with ethyl acetate (18.12 mg GAE·g-1) and ethanol solvents (18.07 mg GAE·g-1), through Soxhlet, and with an acetone-water mixture (14.17 mg GAE·g-1), through maceration, yielded extracts rich in (poly)phenols, with good scavenging and antioxidant activity (98.32 I% for ethanol solvents and 96.31 I% for acetone-water mixture). The antioxidant effect of polyphenols is at least partially due to their capacity to maintain mitochondrial biogenesis and mitophagy, which elevates mitochondrial efficiency, resulting in diminished ROS production, hence re-establishing the mitochondrial quality control. These findings highlight the valorization of Vitis by-products to improve food functional characteristics.

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In the past few years, non-native blue crab has been expanding its range in the Adriatic and Mediterranean Seas. However, when non-indigenous species establish a lasting presence in a novel ecosystem and actively expand into other regions, posing potential risks to local biodiversity and economic harm, they are classified as invasive species. For this study, two different batches of blue crabs were collected: one from the Mediterranean Sea and the other from the Adriatic coast area. Considering the negative ecological impact that blue crab has had and continues to have on the Italian coasts, this work was aimed to evaluate the characteristics of the Adriatic Sea "variant"; another goal was to propose the potential use of blue crab as a commercially profitable source due to its organoleptic characteristics. Data obtained revealed a high protein content, a good lipid profile, a low number of plastic particles, and the absence of toxic metals and pathogenic microorganisms. A deep statistical analysis was conducted to compare different portions of blue crab from the Adriatic and Mediterranean Seas. The results suggest that Callinectes sapidus is beneficial for human consumption and represents a valuable seafood, and its carapace could be used as compliant feed for aquaculture due to its metal composition and microbiological content.

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Shalgam is a fermented product characterized by its color and aroma compounds. However, there is no standard regarding the amount of use of purple carrot, which is the major raw material in production and affects the fermentation and aroma compounds of the product. This present research was designed to examine the effect of purple carrot concentrations on aroma compounds, which are one of the most important characteristics that reflect the quality characteristics of shalgam and affect consumer preferences. Aroma compounds in shalgam juices produced using five different amounts of carrots were analyzed by gas chromatography-flame ionization detector-mass spectrometry (GC-FID-MS). As expected, since the difference between the produced shalgam beverages was only the amount of purple carrots, a qualitative similarity and a quantitative difference were determined in the aroma profiles in general. In the aroma categories defined, terpenes (26 compounds) were the most abundant compounds, followed by esters (17 compounds) and higher alcohols (11 compounds). 88 aroma compounds have been identified in shalgam, and a total of 28 ACs, including 7 terpenes, 7 esters, 3 alcohols, 4 volatile acids, 3 volatile phenols, 1 lactone, 1 norisoprenoid, and 2 naphthalenes, were detected for the first time. The concentration of aromas in the samples varied from 5471.5 to 6490.1 µg/L (p < .05). According to principal component analysis, it was determined that the correlation between the position of the shalgam samples in the coordinate system and the aroma groups was significant. This study shows that purple carrots also affect the aroma compounds of shalgam beverages.

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PURPOSE: To develop a practical method to enable 3D T1 mapping of brain metabolites. THEORY AND METHODS: Due to the high dimensionality of the imaging problem underlying metabolite T1 mapping, measurement of metabolite T1 values has been currently limited to a single voxel or slice. This work achieved 3D metabolite T1 mapping by leveraging a recent ultrafast MRSI technique called SPICE (spectroscopic imaging by exploiting spatiospectral correlation). The Ernst-angle FID MRSI data acquisition used in SPICE was extended to variable flip angles, with variable-density sparse sampling for efficient encoding of metabolite T1 information. In data processing, a novel generalized series model was used to remove water and subcutaneous lipid signals; a low-rank tensor model with prelearned subspaces was used to reconstruct the variable-flip-angle metabolite signals jointly from the noisy data. RESULTS: The proposed method was evaluated using both phantom and healthy subject data. Phantom experimental results demonstrated that high-quality 3D metabolite T1 maps could be obtained and used for correction of T1 saturation effects. In vivo experimental results showed metabolite T1 maps with a large spatial coverage of 240 × 240 × 72 mm3 and good reproducibility coefficients (< 11%) in a 14.5-min scan. The metabolite T1 times obtained ranged from 0.99 to 1.44 s in gray matter and from 1.00 to 1.35 s in white matter. CONCLUSION: We successfully demonstrated the feasibility of 3D metabolite T1 mapping within a clinically acceptable scan time. The proposed method may prove useful for both T1 mapping of brain metabolites and correcting the T1-weighting effects in quantitative metabolic imaging.

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In 1978, Rahimtoola published a successful series of surgical aortic valve replacements (SAVR) on patients with severe aortic stenosis (AS) with congestive heart failure (CHF). He described the perfect prosthesis-patient match as a "prosthetic valve with a functioning opening area that matches the patient's normal functioning valve." This manuscript revisits the forty-six-year journey in pursuit of that perfect match. We address the essential components for the perfect match, such as the usefulness of the current valve sizing techniques using the manufacturer's labeled valve size (MLVS) and sizer, the accuracy of an objective parameter to define the perfect match, and the need and safety to enlarge the patient's annulus and root to accommodate the proper size valve. A thorough literature search was performed using the University of Michigan Medical Library search engine. The population included patients who underwent SAVR. Three individual searches were conducted: (I) valve size and sizing techniques; (II) hemodynamic performance (HP) and prosthesis-patient mismatch (PPM); and (III) aortic root enlargement (ARE) procedures. Excluded were articles not in English, articles that involved animal research, duplicate articles, articles involving valve repair, allograft or autograft replacement, and articles specific to aortic sizing and congenital heart surgery. The emphasis was placed on randomized prospective trials, large registry trials with and without propensity matching, and meta-analysis articles. We discovered that the manufacturer-labeled valve size and sizing technique does not accurately represent the functional opening area of the valve. A pre-operative multidetector computed tomography (CT) scan is an accurate and reproducible method for measuring patient root and annulus dimensions and should be used for pre-operative valve sizing for SAVR. Matching the CT area derived aortic diameter with the true functional diameter of the opening of the prosthetic valve will yield the best prosthesis-patient match. ARE is safe and should be used to attain the best match.

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BACKGROUND: Mineral oil aromatic hydrocarbon (MOAH) analysis in foods is a major analytical challenge. Quantification is associated with a high uncertainty. The sources of uncertainty are multiple, but the major one is related to data interpretation and integration, which is partially derived from insufficiently efficient sample preparation. Recently, an updated ISO method for the analysis of mineral oil in fats and oils and a standard operating procedure for infant formula analysis have been published. Both methods reported significantly different (up to 1.25) distributions of the internal standards used for quantification (i.e., tri-tert-butyl benzene (TBB) and 2-methyl naphthalene (2-MN)) over the different solvent phases used in the saponification step. RESULTS: In this work, a microwave-assisted saponification and extraction method was optimized for MOAH analysis to solve the problem related to the MOAH internal standards partition. The paper examines the impact of the solvent mixture used, the concentration of KOH on the partition of TBB and 2-MN, and the effect of the matrix and the washing step to extract the unsaponifiable fraction containing the mineral oils. SIGNIFICANCE: The optimized procedure achieved a TBB/2-MN ratio of 1.05 ± 0.01 tested in five different fats and oils, namely, sunflower, rapeseed, coconut, palm, and extra virgin olive oils. The method can significantly contribute to reducing the uncertainty of the MOAH quantification when saponification is applied.

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This study assessed saturated mineral oil hydrocarbons (MOSH) and aromatic mineral oil hydrocarbons (MOAH) levels in grower-finisher feeds for pigs supplemented with 5% crude palm oil (CP), crude olive pomace oil (COP), olive pomace acid oil (OPA), or a blend of CP and OPA (50:50, w/w); the contribution of the lipid source to that contamination; and the ability of pigs to accumulate MOH in back fat and loin tissues after 60 days of trial. MOSH and MOAH were analyzed with liquid chromatography (LC)-gas chromatography (GC)-flame ionization detection (FID) after sample preparation. Among the lipid sources, CP had the lowest MOH levels, but CP feeds showed the highest contamination. This, along with the different MOSH profiles, indicated the presence of more significant contamination sources in the feeds than the lipid source. The higher MOH contamination in CP feeds was reflected in the highest MOSH levels in pig back fat, whereas MOAH were not detected in animal tissues. Also, MOSH bioaccumulation in pig tissues was influenced by the carbon chain length. In conclusion, feed manufacturing processes can determine the MOSH contamination present in animal adipose tissues that can be included in human diets.

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Cholesterol analysis by derivatization technique is a time consuming, costly, and complex process while analyzing cholesterol without derivation is a simple, and quick method.Researchers analyzed cholesterol using both derivatization and non-derivatization techniques successfully. The objective of this study was to investigate the effect of derivatization in cholesterol analysis particularly on bakery goods.The retention time of non-derivatized cholesterol (11.62 min) and non-derivatized α-tocopherol standard (11.60 min) was very close in HP-5 capillary GC column andthey eluted together while injected as mixed standard. As a result, cholesterol content determined by non-derivatized technique could be overestimated due to the presence of α-tocopherol inbakery products. The peak resolution (Rs) between derivatized cholesterol and derivatized α-tocopherol standard using the appliedgradient GC condition was 3.1 which is well separated (>1.5) based on AOAC guidelines. The derivatized gas chromatographic cholesterol analysis method was verified by limit of detection (LOD; 0.03 mg/100 g), limit of quantification (LOQ; 0.08 mg/100 g), linearity (R2; 0.999),precision (repeatability: relative standard deviation (RSD) 1.5 %; reproducibility: RSD 1.9 %), and accuracy (102.1 % recovery). The verified cholesterol analysis method was subsequently applied to determine cholesterol content in selected bakery items, yielding a range of 2.76 ± 0.06 mg/100 g (chrysanthemum bread) to 114.26 ± 4.72 mg/100 g (castella).

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BACKGROUND: Zataria multiflora Boiss. is a medicinal and aromatic plant from the Lamiaceae family. It is extensively used in Iranian traditional medicine, mostly as a replacement for Thyme species. This study was focused on the analysis of chemical composition and the distribution and types of trichomes of Z. multiflora grown under different conditions. Equilibrium headspace analysis in combination with GC-FID-MS was used to identify volatile compounds released by aerial parts of Z. multiflora in development stages of 50 and 100% flowering under normal and drought-stress conditions. RESULTS: The main constituents were p-cymene (20.06-27.40%), γ-terpinene (12.44-16.93%), and α-pinene (6.91-16.58%) and thymol (8.52-9.99%). The highest content of p-cymene (27.40%) and thymol (9.99%) was observed in the 50% flowering stage at the 90% field capacity, while the maximum γ-terpinene (16.93%) content was recorded in the 100% flowering stage under normal conditions. Using the SEM method, it was found that peltate glandular and non-glandular trichomes are distributed on the surface of the leaf, stem, and outer side of the calyx. However, capitate trichomes only are detected on the stem and calyx in the 100% flowering and beginning of blooming stages, respectively. The type and structure of trichomes do not vary in different development stages, but they differ in density. The highest number of leaf peltate glandular trichomes was observed in the vegetative and beginning of blooming stages at 50% and 90% field capacity, respectively. Non-glandular trichomes of the stem were observed with high density in both normal and stress conditions, which are more densely in 90% field capacity. CONCLUSIONS: Since this plant has strong potential to be used in the food and pharmacological industries, this study provides valuable information for its cultivation and harvesting at specific phenological stages, depending on desired compounds and their concentrations.

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G-quadruplex DNA structures (G4) are proven to interfere with most genetic and epigenetic processes. Small molecules binding these structures (G4 ligands) are invaluable tools to probe G4-biology and address G4-druggability in various diseases (cancer, viral infections). However, the large number of reported G4 ligands (>1000) could lead to confusion while selecting one for a given application. Herein we conducted a systematic affinity ranking of 11 popular G4 ligands vs 5 classical G4 sequences using FRET-melting, G4-FID assays and SPR. Interestingly SPR data globally align with the rankings obtained from the two semi-quantitative assays despite discrepancies due to limits and characteristics of each assay. In the whole, PhenDC3 emerges as the most potent binder irrespective of the G4 sequence. Immediately below PDS, PDC-360A, BRACO19, TMPyP4 and RHPS4 feature strong to medium binding again with poor G4 topology discrimination. More strikingly, the G4 drugs Quarfloxin, CX5461 and c-PDS exhibit weak affinity with all G4s studied. Finally, NMM and Cu-ttpy showed heterogeneous behaviors due, in part, to their physicochemical particularities poorly compatible with screening conditions. The remarkable properties of PhenDC3 led us to propose its use for benchmarking FRET-melting and G4-FID assays for rapid G4-affinity evaluation of newly developed ligands.

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Fatty acids are present in many foods, either free or esterified. Their presence helps to characterize and classify the food. The nature of these fatty acids is also associated with the treatments applied. To assess the fatty acid profile of these matrices, extractions are carried out using different solvents that influence the nature and lipid profile. The subsequent derivatization of fatty acids to more volatile fatty acyl methyl esters (FAMEs) prior to determination of the fatty acid profile takes into account the nature of the extraction solvent. Thus, the present work proposes to determine the fatty acid profile by Gas Chromatography Flame Ionisation Detector (GC-FID) of two lipid extracts derivatized by the MeOH/KOH and Hexane/MeOH/MeOH-BF3 procedures. Freshly harvested Tetracarpidium conophorum nuts from fields in the Fombap locality were brought to the laboratory where they were boiled (95 °C; 30 min), shelled, cut into small cubes and dried for 48 h at 45 °C. The dried seeds were ground and the resulting paste macerated in hexane for 48 h. The liquid fraction obtained was concentrated using a rotavapor, and the lipid extracts were stored at -15 °C. The egusi pudding was obtained by mixing 100 g of egusi seed paste with 0.50 g of white Piper nigrum powders, then packed in bulrush leaves and steamed for 120 min. After cooking, the product was stored for 4 days at room temperature and reheated twice a day. At the end of the last day, the lipid fraction oil was extracted following the methodology of Bligh and Dyer [1], then concentrated and preserved as before. The lipid extracts were then methylated using MeOH/KOH and Hexane/MeOH/MeOH-BF3 methods before injection into a GC-FID equipped with a Stabil Wax®-DA column. Supelco's standard mix of 37 FAMEs was used to identify and quantify the fatty acids present in the various samples. The results obtained enable us to identify the different fatty acids according to the retention time of their corresponding FAMEs and to quantify them. The fatty acids obtained were classified as saturated and unsaturated (mono and polyunsaturated). These analyses showed that the rapid derivatization method (MeOH/KOH) identified the same number of fatty acids as the Hexane/MeOH/MeOH-BF3 method in the lipid extract from the egusi pudding, whereas the Hexane/MeOH/MeOH-BF3 method identified four more fatty acids in the lipid extract coming from Tetracarpidium conophorum. Although the number of fatty acids was similar, the derivatization method influenced the nature of the fatty acids in the egusi pudding lipid extract. Overall, polyunsaturated fatty acids were the most abundant in the different oils. Omega-3 were the majority subclass in Tetracarpidium conophorum nuts, while omega-6 were in egusi pudding. The derivatization method did not influence the majority fatty acid (alpha linolenic) in Tetracarpidium conophorum nuts, whereas derivatization with BF3 gave trans linoleic and KOH cis linoleic in egusi pudding. These results show that the choice of derivatization method for fatty acid profiling and quantification is very important and depends on the technique and extraction solvents used.

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The volatile profile of Mentha longifolia was observed using GC-MS, GC-FID, FT-IR and 13CNMR. Twenty-two constituents were found to be present in this essential oil, accounting 96.04 (%) of total essential oil and oxegenated monoterpenes were major class of compounds. The key constituents of this essential oil were pieritenone oxide (45.9%), piperitone (17.5%), beta caryophyllene (10.2%), and Germacrene D (5.0%). FT-IR showed peak at 1669 and 1707 cm-1 which may be due to the presence of carbonyl groups. Among the tested compounds, Germacrene D showed highest binding affinity value of -6.8 kcal mol-1 and a pKi value of 6.01. The dsc studies revealed that boiling point of this EO is above 200 °C. Microplate Alamar Blue assay (MABA) was carried out for the assessment of antimycobacterial activity using isoniazid and nicotinic as reference compound and oil was found to be active within conc. range of 0.8-1.6 µg/mL against mycobacterium tuberculosis, hence can act as a potential candidate against antituberculosis.