Gas Chromatography Coupled To Mass Spectrometry Research Articles

Rapid and simultaneous determination of nine volatile solvents in ink entries with improved gas chromatography

Volatile compounds such as alcohols and ethers are added into ballpoint pen inks, gel pen inks and water-based rollerball pen inks as humectants or solvents. The composition of solvents in inks and their amounts of evaporation are critical evidence for identifying the types of pens or dating ink entries. Relative quantification methods using gas chromatography (GC) or gas chromatography coupled to mass spectrometry (GC/MS) were employed to analyze alcohols and ethers in most previously reported studies, but they were not convenient for researchers of the same field to compare results. Besides, those methods are time-consuming, with an average time of 23−36 min per run. Therefore, in this work a rapid quantification method was established to simultaneously determine nine volatile solvents commonly existed in ink entries, including ethylene glycol, 1,2-propanediol, 1,3-propanediol, glycerol, diethylene glycol, triethylene glycol, benzyl alcohol, 2-phenoxyethanol (PE) and diethylene glycol monoethyl ether (DGME), while 1,3-butanediol was used as the internal standard. A GC system equipped with flame ionization detector (FID) was adopted to separate the nine target analytes. The analysis time was reduced to 9–12 min. The linearity of the calibration curves was good in the ranges of 10–3000 ng/cm for all target analytes, and Pearson correlation coefficients were all greater than 0.999. The results indicate that the established method provides sensitive, precise, and accurate quantification of nine volatile solvents in ink entries. What’s more, this method raises analytical efficiency greatly and has lower requirements of instruments, showing promising application in questioned document examination and ink dating.

In Vitro and In Silico Studies of Antimicrobial, and Antioxidant Activities of Chemically Characterized Essential Oil of Artemisia flahaultii L. (Asteraceae).

The present study investigated the antioxidant and antimicrobial activities as well as characterized the chemical composition of the essential oils (EO) isolated from Artemisia flahaultii (EOF). EOF was extracted using hydro-distillation, and the chemical composition of EOF was ascertained by gas chromatography coupled with mass spectrometry (GC/MS). To assess antioxidant capacity, three tests were used: the 2,2-diphenyl-1-picrylhydrazil (DPPH), the total antioxidant capacity (TAC) and the ferric-reducing antioxidant power (FRAP) test. The antimicrobial activity of EOF was investigated using the diffusion assay and minimal inhibitory concentration assays (MICs). By use of in silico structure-activity simulations, the inhibitory potency against nicotinamide adenine dinucleotide phosphate (NADPH), physicochemical characters, pharmaco-centric properties and absorption, distribution, metabolism, excretion (ADME) characteristics of EOF were determined. GC/MS analysis reveals 25 components majorly composed of D-Limonene (22.09%) followed by β-pinene (15.22%), O-cymene (11.72%), β-vinylnaphthalene (10.47%) and benzene 2,4-pentadiynyl (9.04%). The capacity of DPPH scavenging by EOF scored an IC50 of 16.00 ± 0.20 µg/mL. TAC revealed that the examined oils contained considerable amounts of antioxidants, which were determined to be 1094.190 ± 31.515 mg ascorbic acid equivalents (AAE)/g EO. Results of the FRAP method showed that EOF exhibited activity with EC50 = 6.20 ± 0.60 µg/mL. Values for minimal inhibitory concentration (MIC) against certain clinically important pathogenic bacteria demonstrate EOF's potent antibacterial activity. MIC values of 1.34, 1.79, and 4.47 μg/mL against E. coli, B. subtilis and S. aureus were observed respectively. EOF exhibited significant antifungal activities against two stains of fungi: F. oxysporum and C. albicans, with values of 10.70 and 2.23 μg/mL, respectively. Of the total, 25 essential oils were identified. 2,4-Di-tert-butylphenol and capillin were the most active molecules against NADPH. The ADME prediction revealed that EOF was characterized by useful physicochemical characteristics and pharmaco-centric properties. The findings of this study show that the EOF can be used as an alternative to treat microbial resistance. Based on the in silico studies, EOF can be used as an "eco-friendly" NADPH inhibitor.

Phytochemical analysis and antibacterial/antifungal activity of the essential oil of Phlomis olivieri Benth in Iran.

Phlomis olivieri Benth. is an aromatic plant endemic to Iran belonging to the Lamiaceae family. It is used to treat pain, stomach ache and common cold in Iranian traditional medicine. P. olivieri also has valuable biological properties including antioxidant, antimicrobial and analgesic ones. This was the first study designed to assess the quality, quantity and antimicrobial activity of Phlomis olivieri Benth. essential oil (POEO). Samples were randomly collected from flowering twigs of this species in three locations between Azeran and Kamoo in Kashan, Iran at peak flowering in June 2019. Water distillation extraction was used to obtain the POEO the quantity of which was calculated by weight. Gas chromatography coupled to mass spectrometry (GC/MS) was also used for POEO qualitative analysis, which revealed its chemical compounds and their percentages. Antimicrobial activity of POEO was also determined using the agar well diffusion method. Minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC) were also measured using the broth microdilution method. The results of the quantitative and qualitative analysis showed that the POEO yield was ~ 0.2292% and its main chemical compounds included the sesquiterpenes germacrene D (26.43%), β-caryophyllene (20.72%), elixene (6.58%), β-trans-farnesene (6.17%), β-Cyclogermacrane (5.04%), germacrene B (4.73%), α-humulene (4.22%), and monoterpene α-pinene (3.22%). The agar diffusion method demonstrated the highest antimicrobial activity of POEO (MIC ~ 14.50mm) was against the Gram-positive species Streptococcus pyogenes. The POEO also showed the strongest inhibitory and lethal activity against the gram-negative bacterial species Pseudomonas aeruginosa (MIC < 62.50μg/mL) and S. paratyphi-A (MIC < 62.50μg/mL and MBC = 125μg/mL), and fungal species Candida albicans (MIC and MBC = 250μg/mL) as compared to control-positive antibiotics. Therefore, POEO is a valuable natural alternative rich in sesquiterpenes with strong antimicrobial and antifungal activities against some fungal and bacterial strains. It can also be used in the pharmaceutical, food and cosmetic industries.

Comparative study of seed roasting effects on Sesamum radiatum Schumach. &amp; Thonn and Sesamum indicum L. oils quality

Several species of sesame have been extensively studied but little is known about Sesamum radiatum (SR). In this work, seeds roasting impact on two Sesamum spp, SR and S. indicum (SI) oils quality was studied. Physicochemical parameters (PP), fatty acids profile (FAL) and antioxidant activities were evaluated using spectrophotometry methods and gas chromatography coupled to mass spectrometry (GC-MS). Unroasted seeds (US) of SR oil extraction showed a yield of 40.26 ± 0.86% while roasted seeds (RS) at different temperatures (145-200°C) demonstrated a yield of 40.11 ± 1.36%. Evaluation of PP of oils according to the French Standardization Association (AFNOR) standards showed the following results: refractive index: 1.47435-1.47665 for SR and 1.46660-1.47065 for SI; acid number: 2.01-3.35 for RS against 10.04±0.53 mg KOH/g for US; saponification number: 186.82-191.53 for SR and 189.74-190.42 mg KOH/g for SI. Iodine value: 100.31-127.74 for SR against 117.96-128.04 g I2/100 g for SI; peroxide value: 1.19-4.00 for SR against 1.66-2.58 meq/Kg active O2 for SI. FAL was slightly modified during roasting showing that SR oil is an oleic-linoleic oil. More, SR oil demonstrated twice antioxidant activity than SI. These results demonstrated that roasting has positive effects on SR oil nutritional quality. SR oil could be recommended in food after toxicity studies.

Fatty Acid Alkyl Ester Production by One-Step Supercritical Transesterification of Beef Tallow by Using Ethanol, Iso-Butanol, and 1-Butanol

The effect of temperature was studied on the synthesis of fatty acid alkyl esters by means of transesterification of waste beef tallow using ethanol and, iso-butanol and 1-butanol at supercritical conditions. These alcohols are proposed for the synthesis of biodiesel in order to improve the cold flow properties of alkyl esters. Alcohol–beef tallow mixtures were fed to a high-pressure high-temperature autoclave at a constant molar ratio of 45:1. Reactions were carried out in the ranges of 310–390 °C and 310–420 °C for ethanol and iso-butanol, respectively; meanwhile, synthesis using 1-butanol was assessed only at 360 °C. After separation of fatty acid alkyl esters, these samples were characterized by nuclear magnetic resonance (NMR) and gas chromatography coupled to mass spectrometry (GC-MS) to quantify yields, chemical composition, and molecular weight. Results indicated that yields enhanced as temperature increased; the maximum yields for fatty acid ethyl esters (FAEEs) were attained at 360 °C, and for fatty acid butyl esters (FABEs) were achieved at 375 °C; beyond these conditions, the alkyl ester yields reached equilibrium. Concerning the physicochemical properties of biodiesel, the predicted cetane number and cloud point were enhanced compared to those of fatty acid methyl esters.

Non-Lactic Probiotic Beverage Enriched with Microencapsulated Red Propolis: Microorganism Viability, Physicochemical Characteristics, and Sensory Perception

This work aimed to develop a non-dairy functional beverage fermented with probiotic strains and fortified with Brazilian red propolis (microencapsulated and extracted). The non-dairy matrix consisted of oats (75 g), sunflower seeds (175 g), and almonds (75 g). It was fermented by a starter co-culture composed of Lactiplantibacillus plantarum CCMA 0743 and Debaryomyces hansenii CCMA 176. Scanning electron microscopy analysis was initially performed to verify the integrity of the microcapsules. The viability of the microorganisms after fermentation and storage, chemical composition (high performance liquid chromatography (HPLC) and gas chromatography coupled to mass spectrometry (GC-MS) analyses), rheology, antioxidant activity, and sensory profile of the beverages were determined. After fermentation and storage, the starter cultures were well adapted to the substrate, reducing the pH (6.50 to 4) and cell count above 7.0 log CFU/mL. Lactic acid was the main organic acid produced during fermentation and storage. In addition, 39 volatile compounds were detected by gas chromatography coupled to mass spectrometry (GC-MS), including acids, alcohols, aldehydes, alkanes, alkenes, esters, ethers, phenols, terpenes, and others. The addition of propolis extract increased the antioxidant and phenolic activity and the presence of volatile esters but reduced the beverage’s acceptability. The addition of microencapsulated propolis was more associated with the presence of higher alcohols and had similar acceptance to the control beverage. The combination of a non-dairy substrate, a starter co-culture, and the addition of propolis led to the development of a probiotic beverage with great potential for health benefits.

Survival and Demography of the Tomato Borer (Tuta absoluta) Exposed to Citrus Essential Oils and Major Compounds †

Tuta absoluta is a pest of importance: quick to disperse and difficult to control due to the cases of resistance to insecticide active ingredients. Thus, studies using essential oils (EOs) to search for new molecules should be intensified. The objective of the present study was to evaluate the toxicity of EOs from Citrus aurantifolia (lime), Citrus aurantium (petitgrain) and Citrus aurantium bergamia (bergamot) and its major compounds against T. absoluta in a topical application test. Additionally, the demographic parameters of T. absoluta were studied after the topical application of EOs. The median lethal time (LT50) of the population was 12h for the three EOs tested. The median lethal concentration (LC50) was 33.75, 38.78 and 35.05 µg µL−1 for C. aurantifolia, C. aurantium and C. aurantium bergamia, respectively. As found using gas chromatography coupled to mass spectrometry (GC-MS) quantification, 44.74% of the EO of C. aurantifolia is α-terpineol, while 55.45% and 58.12% of the EO of C. aurantium and C. aurantium bergamia, respectively, is linalyl acetate. The toxicity of the major compounds was tested at concentrations equivalent to the LC50 of the EOs, that is, 16.2 µg µL−1 for α-terpineol, and 25.8 µg µL−1 for linalyl acetate, using topical application. Both of the major compounds showed less toxicity than the EOs. In the sublethal effects tests, all the EOs negatively affected the demographic parameters of T. absoluta, with a decrease in the duration of larval instars, duration of the pupal period, fecundity, oviposition and viability of the eggs, implying a reduction in the population growth parameters of this pest. The EOs of lime, petitgrain and bergamot are toxic to T. absoluta, and low concentrations cause deleterious effects on the reproductive and population parameters of T. absoluta.

Chemical Composition and Antimicrobial Potential of a Plant-Based Substance for the Treatment of Seborrheic Dermatitis

Seborrheic dermatitis (SD) is the most prevalent dermatological disease, occurring in up to 50% of newborns, children, and adults around the world. The antibacterial and antifungal resistance contributed to the search for new natural substances and the development of a novel substance based on Melaleuca alternifolia (M. alternifolia) leaf oil (TTO), 1,8-cineole (eucalyptol), and α-(-)-bisabolol. Thus, this work aimed to determine the chemical composition of the novel plant-based substance and to evaluate its antimicrobial activity against standard microorganisms involved in the pathogenesis of SD. Moreover, the chemical composition of the substance was analyzed by gas chromatography coupled with mass spectrometry (GC/MS). Staphylococcus epidermidis (S. epidermidis), Staphylococcus aureus (S. aureus), Micrococcus luteus (M. luteus), and Candida albicans (C. albicans) were used for antimicrobial and antifungal assays by means of the broth microdilution method to determine the minimal inhibitory concentration (MIC). Finally, the substance's ability to inhibit Malassezia furfur (M. furfur) was evaluated. Eighteen compounds from different chemical groups were identified by GC/MS. The major biologically active compounds of the substance were terpinen-4-ol (20.88%), 1,8-cineole (22.28%), (-)-α-bisabolol (25.73%), and o-cymene (8.16%). The results showed that the substance has a synergistic antimicrobial and antifungal activity, while S. epidermidis and C. albicans strains were the most susceptible. Furthermore, the substance inhibited M. furfur, which is a main pathogen involved in the pathogenesis of SD and clinical manifestations. It can be concluded that the novel plant-based substance has a promising potential against M. furfur and scalp commensal bacteria and may be helpful for the development of new drugs for treatment of dandruff and SD.

Use of Gas Chromatography and SPME Extraction for the Differentiation between Healthy and Paenibacillus larvae Infected Colonies of Bee Brood—Preliminary Research

Paenibacillus larvae is a deadly pathogen for bee brood, which can lead to the death of entire colonies. The presence of specific volatile organic compounds (VOCs) in the hive may be related to the occurrence of this bacterium in brood. Compositions of those volatile fractions present in healthy brood from control colonies and the brood without symptoms of infection collected from the colonies infected by P. larvae were compared using gas chromatography coupled with mass spectrometry (GC-MS) and solid phase microextraction (SPME). Among the seven compounds detected and quantified, the relative concentrations of 3-carene and limonene significantly differentiated the brood from healthy and infected colonies. Based on the ratio analysis, the samples were differentiated in terms of the number of emitted VOCs.

Phytochemical Characterization of Cannabis sativa L. Roots from Northeastern Brazil.

This article describes the phytochemical study of Cannabis sativa roots from northeastern Brazil. The dried plant material was pulverized and subjected to exhaustive maceration with ethanol at room temperature, obtaining the crude ethanolic extract (Cs-EEBR). The volatile compounds were analyzed by gas chromatography coupled with mass spectrometry (GC/MS), which allowed to identify 22 compounds by comparing the linear retention index (LRI), the similarity index (SI) and the fragmentation pattern of the constituents with the literature. By this technique the major compounds identified were: friedelan-3-one and β-sitosterol. In addition, two fractions were obtained from Cs-EEBR by classical column chromatography and preparative thin layer chromatography. These fractions were analyzed by NMR and IR and together with the mass spectrometry data allowed to identify the compounds: epifriedelanol, friedelan-3-one, β-sitosterol and stigmasterol. The study contributed to the phytochemical knowledge of Cannabis sativa, specifically the roots, as there are few reports on the chemical constituents of this part of the plant.

Two Fast GC-MS Methods for the Measurement of Nicotine, Propylene Glycol, Vegetable Glycol, Ethylmaltol, Diacetyl, and Acetylpropionyl in Refill Liquids for E-Cigarettes.

The use of e-cigarettes (ECs) has become increasingly popular worldwide, even though scientific results have not established their safety. Diacetyl (DA) and acetylpropionyl (AP), which can be present in ECs, are linked with lung diseases. Ethyl maltol (EM)-the most commonly used flavoring agent-can be present in toxic concentrations. Until now, there is no methodology for the determination of nicotine, propylene glycol (PG), vegetable glycerin (VG), EM, DA, and acetylpropionyl in e-liquids that can be used as a quality control procedure. Herein, gas chromatography coupled with mass spectrometry (GC-MS) was applied for the development of analytical methodologies for these substances. Two GC-MS methodologies were developed and fully validated, fulfilling the standards for the integration in a routine quality control procedure by manufacturers. As proof of applicability, the methodology was applied for the analysis of several e-liquids. Differences were observed between the labeled and the experimental levels of PG, VG, and nicotine. Three samples contained EM at higher concentrations compared to the other samples, while only one contained DA. These validated methodologies can be used for the quality control analysis of EC liquid samples regarding nicotine, PG, and VG amounts, as well as for the measurement of the EM.

Investigating the Use of SARS-CoV-2 (COVID-19) Odor Expression as a Non-Invasive Diagnostic Tool-Pilot Study.

Since the beginning of the COVID-19 pandemic, there has been enormous interest in the development of measures that would allow for the swift detection of the disease. The rapid screening and preliminary diagnosis of SARS-CoV-2 infection allow for the instant identification of possibly infected individuals and the subsequent mitigation of the disease spread. Herein, the detection of SARS-CoV-2-infected individuals was explored using noninvasive sampling and low-preparatory-work analytical instrumentation. Hand odor samples were obtained from SARS-CoV-2-positive and -negative individuals. The volatile organic compounds (VOCs) were extracted from the collected hand odor samples using solid phase microextraction (SPME) and analyzed using gas chromatography coupled with mass spectrometry (GC-MS). Sparse partial least squares discriminant analysis (sPLS-DA) was used to develop predictive models using the suspected variant sample subsets. The developed sPLS-DA models performed moderately (75.8% (±0.4) accuracy, 81.8% sensitivity, 69.7% specificity) at distinguishing between SARS-CoV-2-positive and negative -individuals based on the VOC signatures alone. Potential markers for distinguishing between infection statuses were preliminarily acquired using this multivariate data analysis. This work highlights the potential of using odor signatures as a diagnostic tool and sets the groundwork for the optimization of other rapid screening sensors such as e-noses or detection canines.

Essential Oils and Biological Activities of Eucalyptus falcata, E. sideroxylon and E. citriodora Growing in Tunisia

Many plants are able to synthesize essential oils (EOs), which play key roles in defense against weeds, fungi and pests. This study aims to analyze the chemical composition and to highlight the antioxidant, antimicrobial and phytotoxic properties of the EOs from Eucalyptus falcata, E. sideroxylon and E. citriodora growing in Tunisia. EOs were analyzed by gas chromatography coupled to mass spectrometry (GC/MS) and their antioxidant properties were determined by total antioxidant capacity (TAC), DPPH and ABTS assays. The phytotoxic potential was assessed against weeds (Sinapis arvensis, Phalaris canariensis) and durum wheat crop (Triticum durum) and compared to chemical herbicide glyphosate. The antifungal activity was investigated in vitro against eight target fungal strains. All EOs displayed a specific richness in oxygenated monoterpenes (51.3-90%) and oxygenated sesquiterpenes (4.8-29.4%), and 1,8-cineole, citronellal, citronellol, trans-pinocarveol, globulol, spathulenol and citronellyl acetate were the main constituents. Eucalyptus EOs exhibited remarkable antioxidant activity and E. citriodora oil exhibited significant activity when compared with E. falcata and E. sideroxylon EOs. The phytotoxic potential of the tested oils had different efficacy on seed germination and the growth of seedlings and varied among tested herbs and their chemical composition variability. Their effectiveness was better than that of glyphosate. At the post-emergence stage, symptoms of chlorosis and necrosis were observed. Furthermore, a decrease in chlorophyll and relative water content, electrolyte leakage and high levels of MDA and proline were indicators of the oxidative effects of EOs and their effectiveness as bioherbicides. Moreover, all the EOs exhibited moderate fungitoxic properties against all the tested fungal strains. Therefore, according to the obtained results, Eucalyptus EOs could have potential application as natural pesticides.

Metabolomic and transcriptomic response to imatinib treatment of gastrointestinal stromal tumour in xenograft-bearing mice

BackgroundAlthough imatinib is a well-established first-line drug for treating a vast majority of gastrointestinal stromal tumours (GIST), GISTs acquire secondary resistance during therapy. Multi-omics approaches provide an integrated perspective to empower the development of personalised therapies through a better understanding of functional biology underlying the disease and molecular-driven selection of the best-targeted individualised therapy. In this study, we applied integrative metabolomic and transcriptomic analyses to elucidate tumour biochemical processes affected by imatinib treatment. Materials and methodsA GIST xenograft mouse model was used in the study, including 10 mice treated with imatinib and 10 non-treated controls. Metabolites in tumour extracts were analysed using gas chromatography coupled with mass spectrometry (GC-MS). RNA sequencing was also performed on the samples subset (n=6). ResultsMetabolomic analysis revealed 21 differentiating metabolites, whereas next-generation RNA sequencing data analysis resulted in 531 differentially expressed genes. Imatinib significantly changed the profile of metabolites associated mainly with purine and pyrimidine metabolism, butanoate metabolism, as well as alanine, aspartate, and glutamate metabolism. The related changes in transcriptomic profiles included genes involved in kinase activity and immune responses, as well as supported its impact on the purine biosynthesis pathway. ConclusionsOur multi-omics study confirmed previously known pathways involved in imatinib anticancer activity as well as correlated imatinib-relevant downregulation of expression of purine biosynthesis pathway genes with the reduction of respectful metabolites. Furthermore, considering the importance of the purine biosynthesis pathway for cancer proliferation, we identified a potentially novel mechanism for the anti-tumour activity of imatinib. Based on the results, we hypothesise metabolic modulations aiming at the reduction in purine and pyrimidine pool may ensure higher imatinib efficacy or re-sensitise imatinib-resistant tumours.

Inhibitory Activity of Essential Oils of Mentha spicata and Eucalyptus globulus on Biofilms of Streptococcus mutans in an In Vitro Model.

The aim of this study was to evaluate the inhibitory activity of the commercially available essential oils of Mentha spicata (spearmint) and Eucalyptus globulus (eucalyptus) on Streptococcus mutans ATCC 25175 biofilms in vitro, emulating dental plaque conditions. The composition of the essential oils (EOs) was determined using gas chromatography coupled with mass spectrometry (GC-MS), with the main metabolites being Carvone (57.93%) and Limonene (12.91%) for Mentha spicata and 1,8-Cineole (Eucalyptol) (65.83%) for Eucalyptus globulus. The inhibitory activity was evaluated using the methods of agar-well diffusion and colorimetric microdilution. The inhibition halos were 18.3 ± 0.47 mm and 27.0 ± 0.82 mm, and the MICs were 1.8484 mg/mL and 1.9168 mg/mL for the EOs of Mentha spicata and Eucalyptus globulus, respectively. The activity against the biofilms was evaluated on a substrate of bovine enamel pieces using a basal mucin medium (BMM) in anaerobic conditions with daily sucrose exposition cycles in order to emulate oral cavity conditions. The EOs were applied in a concentration of 0.5% in a sterile saline vehicle with 1% polysorbate 20. After 72 h of cultivation, a significant reduction was observed (p < 0.001%) on the biofilm biomass, which was evaluated by its turbidity in suspension and using a count of the recoverable organisms with regards to the control. The effects of the Eos were not significantly distinct from each other. The EOs showed antimicrobial activity against both the Streptococcus mutans planktonic and biofilm cultures. Thus, EOs may have great potential for the development of pharmaceutical and sanitary products for oral health.

On-Site Detection of Volatile Organic Compounds (VOCs).

Volatile organic compounds (VOCs) are of interest in many different fields. Among them are food and fragrance analysis, environmental and atmospheric research, industrial applications, security or medical and life science. In the past, the characterization of these compounds was mostly performed via sample collection and off-site analysis with gas chromatography coupled to mass spectrometry (GC-MS) as the gold standard. While powerful, this method also has several drawbacks such as being slow, expensive, and demanding on the user. For decades, intense research has been dedicated to find methods for fast VOC analysis on-site with time and spatial resolution. We present the working principles of the most important, utilized, and researched technologies for this purpose and highlight important publications from the last five years. In this overview, non-selective gas sensors, electronic noses, spectroscopic methods, miniaturized gas chromatography, ion mobility spectrometry and direct injection mass spectrometry are covered. The advantages and limitations of the different methods are compared. Finally, we give our outlook into the future progression of this field of research.

CHEMICAL COMPOSITION AND ANTIOXIDANT ACTIVITIES OF TANNINS EXTRACT FROM ALOE SAPONARIA

The objective of this work was to study the chemical composition and antioxidant activity of tannins extract of Aloe saponaria (TEAS). The Aloe saponaria (syn. Aloe maculata) is a succulent plant belonging to the Xanthorrhoeaceae family, this succulent plant native to South Africa was introduced in Morocco as an ornamental plant, rustic and easy to grow. In order to ensure this, morphological and histological study method of the species, phytochemical screening, characterization of TEAS by gas chromatography coupled to mass spectrometry (GC/MS), and the study of antioxidant activity by two methods (2,2-diphenyl-1-picrylhydrazyl (DPPH) and total antioxidant capacity (TAC) assays) were examined. The results of phytochemical screening indicated that the Aloe saponaria leaf was rich of alkaloids, tannins catechics, flavonoids, sterols, triterpenes, oses, holosides, mucilages and reducing sugars. In addition, the main constituents of TEAS identified by GC/MS analysis were Linolenic acid (32.22%), Palmitic acid (17.42%), and Phytol (11.30%). Regarding antioxidant activity, the TEAS showed a significant antioxidant effect.

Characterization of terpenoids frompseudognaphalium gaudichaudianum (DC)anderb, wira-wira by GC/MS, active principles with possible use in COVID-19 infection prevention

Pseudognaphalium gaudichaudianum (DC.) Anderb., (asteraceae) is a small herbaceous plant that grows in the heights and in mountainous places. Known by the vernacular name "Wira Wira'', it is well reputed in traditional medicine by aymara communities to treat respiratory diseases like cough, common cold, bronchitis, and pneumonia in the highlands of Bolivia. Due of its expectorant properties, P. gaudichaudianum has been proposed as a phytomedicine to prevent infection by COVID-19, in infusions and vaporization. In this study, the terpenoids from its essential oil were characterized by Gas Chromatography Coupled to Mass Spectrometry (GC/MS). The analysis showed the presence of 1 monoterpenoid, 11 sesquiterpenoids, 2 diterpenoids and 4 minor unidentified compounds. The major compounds identified were β- Eudesmene (16.35%), Rosifoliol (15.29%), Guaia 1(10),1 1-diene (15.20%), Guaia 6,9 diene (14.46%), α-Pinene (11.32%) and α-Guaiene (6.16%).

Archaeological Evidence for the Dietary Practices and Lifestyle of 18th Century Lisbon, Portugal—Combined Steroidal Biomarker and Microparticle Analysis of the Carbonized Faecal Remains

The study of the urban context in the contemporary center of Portugal’s capital city uncovered traces of daily lives that were abruptly interrupted and utterly transformed by the Great Lisbon Earthquake on the morning of 1 November 1755. Charred organic residue was recovered from a cylindrical vessel excavated from the storage area of the town house at the Rossio square. The archaeological sample was studied through a multi-analytical approach based on microstructural, elemental and biomolecular characterization by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FT-IR), variable pressure scanning electron microscopy coupled to energy dispersive X-ray spectroscopy (VP-SEM-EDS), and gas chromatography coupled with mass spectrometry (GC-MS). The residue was identified as human faeces collected in the ceramic vessel for disposal, and further analysis provided additional information about diet and the living conditions in the 18th century.

Sensitive and High-Throughput Analysis of Volatile Organic Species of S, Se, Br, and I at Trace Levels in Water and Atmospheric Samples by Thermal Desorption Coupled to Gas Chromatography and Inductively Coupled Plasma Mass Spectrometry.

Emissions of volatile organic sulfur (S), selenium (Se), bromine (Br), and iodine (I) species from aquatic ecosystems represent an important source of these elements into the atmosphere. Available methods to measure these species are either not sensitive enough or not automated, which hinder a full understanding of species distribution and production mechanisms. Here, we present a sensitive and high-throughput method for the simultaneous and comprehensive quantification of S, Se, Br, and I volatile organic species in atmospheric and aqueous samples using a preconcentration step onto sorbent tubes and subsequent analysis by thermal desorption coupled to gas chromatography and inductively coupled plasma mass spectrometry (TD-GC-ICP-MS). Selected commercially available sorbent tubes, consisting of mixed porous polymer and graphitized black carbon, offered the highest trapping capacity and lowest loss of species when stored at -20 °C for 28 days after sampling. After optimization of the TD-GC-ICP-MS method, absolute detection limits were better than 3.8 pg, 9.1 fg, 313 fg, and 50 fg, respectively, for S, Se, Br, and I species. As a proof of concept, the concentrations of target species were determined in aqueous and continuously collected atmospheric samples during a cruise in the Baltic and North Seas. Moreover, unknown S, Br, and I volatile species were detected in both aqueous and atmospheric samples demonstrating the full potential of the method.