Gas Chromatographic Method Research Articles

Detecting olive oil counterfeiting by dilution with rapse and sunflower oils according to the triacyl glyceride profile using the method of gas chromatography

Olive oil is a valuable food product, a source of monounsaturated fatty acids, antioxidants, including polyphenolic nature, as well as terpenes and phytosterols. The high cost, along with the demand for special dietary properties, makes olive oils an attractive target for counterfeiting, most often done by diluting olive oil with cheaper sunflower and rapeseed oils. Considering that traditional indicators of identification of vegetable oils do not allow to detect such falsification; it is relevant to search for new objective indicators and methods for identifying olive oils. The purpose of the research is to justify the use of triacylglyceride profile for identification and detection of falsification of olive oils. The objectives of the research include the selection and adaptation of an effective and affordable method for determining the triacylglyceride profile; identification of reliable markers of identification and falsification of olive oils, carried out by diluting them with sunflower or rapeseed oils; establishing dependencies that allow determining the amount of sunflower or rapeseed oil mixed with olive oil. Gas chromatography with a flame ionization detector has been used as the main research method. Based on the studies carried out, the method of gas chromatography with a flame initiation detector has been adapted for the analysis of the triacylglyceride profile of olive, sunflower and rapeseed oils, as well as their mixtures. Markers have been established that make it possible to unambiguously identify the falsification of olive oil by diluting it with sunflower or rapeseed oil. Calibration graphs and dependencies are proposed that allow you to set the amount of sunflower or rapeseed oil in a mixture with olive oil.

N-nitrosamines in Qingdao dried aquatic products and dietary risk assessment

ABSTRACT N-nitrosamines are human carcinogens commonly present in dried aquatic products. A method of gas chromatography – mass spectrometry combined with steam distillation was developed for the determination of 9 N-nitrosamines in dried aquatic products in Qingdao, China, with which 300 samples of fish, squid, shrimp and sea cucumber collected from Qingdao were analysed. A health risk assessment was conducted based on determined levels of N-nitrosamines by using estimated daily intake and slope factors. Results showed that fish products was the category with the highest content of N-nitrosamines, whereas squid and shrimp products were the categories with the highest frequency of presence of N-nitrosamines. The average estimated cancer risk of N-nitrosamines in dried aquatic products in Qingdao ranged from 3.57 × 10−8 to 3.53 × 10−5. Nitrosodimethylamine, N-Nitrosodiethylamine and N-Nitrosodibutylamine could be considered to pose a potential cancer risk to residents in Qingdao.

Thermodynamic Characterization of Polyetherimide/Single-Walled Carbon Nanotube Composites.

The aim of this study is to examine the interactions of composite materials obtained by adding single-walled carbon nanotubes (SWCNT) to polyetherimide (ULTEM) in different weight ratios with various organic solvents, and to evaluate the solubility of composites in these organic solvents. The characterization of prepared composites was performed with SEM analysis. Thermodynamic properties of ULTEM/SWCNT composites were determined by the inverse gas chromatography (IGC) method at 260-285°C in infinite dilution. According to the IGC method, the retention behaviors were examined by passing different organic solvent vapors over the composites used as stationary phase, and retention diagrams were drawn using the obtained retention data. Thermodynamic parameters including Flory-Huggins interaction parameters (${\chi}_{12}^{\infty }$), equation of state interaction parameters (${\chi}_{12}^{\ast }$), weight fraction activity coefficients in infinite dilution (${\Omega}_1^{\infty }$), effective exchange energy parameters (${\chi}_{\mathrm{eff}}$), partial molar sorption enthalpies ($\Delta{\overline{H}}_1^S$), partial molar dissolution enthalpies in infinite dilution ($\Delta{\overline{H}}_1^{\infty }$) and molar evaporation enthalpies ($\Delta{\overline{H}}_v$) were calculated using the linear retention diagrams. According to ${\chi}_{12}^{\infty }$, ${\chi}_{12}^{\ast }$, ${\Omega}_1^{\infty }$ and ${\chi}_{\mathrm{eff}}$ values, organic solvents were found to be poor solvents for composites at all temperatures. Besides, the solubility parameters of composites were determined by IGC method at infinite dilution.

Formaldehyde Gas Sensors Fabricated with Polymer-Based Materials: A Review

Formaldehyde has been regarded as a common indoor pollutant and does great harm to human health, which has caused the relevant departments to pay attention to its accurate detection. At present, spectrophotometry, gas chromatography, liquid chromatography, and other methods have been proposed for formaldehyde detection. Among them, the gas sensor is especially suitable for common gaseous formaldehyde detection with the fastest response speed and the highest sensitivity. Compared with the formaldehyde sensors based on small molecules, the polymer-based sensor has higher selectivity but lower sensitivity because the polymer-based sensor can realize the specific detection of formaldehyde through a specific chemical reaction. Polymer-related formaldehyde sensors can be very versatile. They can be fabricated with a single polymer, molecularly imprinted polymers (MIP), polymer/metal-oxide composites, different polymers, polymer/biomass material composites, polymer/carbon material composites, and polymer composites with other materials. Almost all of these sensors can detect formaldehyde at ppb levels under laboratory conditions. Moreover, almost all polymer nanocomposite sensors have better sensitivity than single polymer sensors. However, the sensing performance of the sensor will be greatly reduced in a humid environment due to the sensitive coating on the gaseous formaldehyde sensor, which is mostly a hydrophilic polymer. At present, researchers are trying to improve the sensitive material or use humidity compensation methods to optimize the gaseous formaldehyde sensor. The improvement of the practical performance of formaldehyde sensors has great significance for improving indoor living environments.

Effect of animal waste on bioremediation of soil contaminated with spent hydrocarbon from auto mechanic workshop in Keffi, Nasarawa State, Nigeria

Petroleum hydrocarbon is a major environmental pollutant throughout the world today because exploration and downstream utilization are associated with economic development. This work focus on effect of animal waste on bioremediation of soil contaminated spent hydrocarbon from auto mechanic workshop in Keffi. Isolation of bacteria and studies on utilized spent hydrocarbon supplemented with animal waste was carried out using standard microbiological methods and identified using 16s rRNA molecular techniques. The total spent hydrocarbon utilization was determined using Gas Chromatographic methods. The highest total bacteria count was recorded from High court (2.1 x105 cfu/g) and the lowest was from Keffi garage2 (1.2 x105 cfu/g). bacteria isolated and molecularly identified were Pectobacterium wasabiae, Pseudomonas fluorescens, and Priestia aryabhattai. The utilization of spent hydrocarbon after 4weeks of the experiment set up at ambient temperature Pseudomonas fluorescens recorded highest utilization of spent hydrocarbon amended with Poultry dropping and Cow dunk with 16.23±1.21 mg/ml and 13.44±0.23 mg/ml and Pectobacterium wasabia recorded the least with 8.12±0.20 mg/ml and 10.00±1.43. At temperature of 35 ℃ Pseudomonas fluorescens recorded highest utilization of spent hydrocarbon amended with Cow dunk and Poultry dropping with 17.13±1.11 mg/ml and 15.14±1.13 mg/ml while Priestia aryabhattai recorded the lowest from Poultry dropping with 6.10±0.06 mg/ml and Cow dunk with 8.23±0.03 mg/ml. at 40 ℃ the highest utilization was recorded by Priestia aryabhattai from Cow dunk amended spent hydrocarbon with 18.13±1.01 mg/ml and Poultry dropping with 16.24±1.33 mg/ml. from the findings of this study temperature plays a key role spent hydrocarbon that containment our environmental

Determining methane uptake in tropical agroforestry soils: a case for inclusion in REDD+

This study aims to measure possible seasonal methane (CH4) fluxes in tropical agroforestry soils to enhance the case for agroforestry’s inclusion in the Reducing Emissions from Deforestation and Forest Degradation (REDD+) program. The role of CH4 in the REDD+ program is currently uncertain. Air samples and environmental variables from the soil-atmosphere interface of the Maya Mountain Research Farm in southern Belize were collected three times per week throughout April and July of 2019. Samples were analyzed using the static chamber and gas chromatography method. The average CH4 flux for the dry season was − 0.02 mg CH4 m−2 h−1 and − 0.03 mg CH4 m−2 h−1 for the wet season, with negative values indicative of uptake. There was a negative correlation between CH4 flux and rainfall in the dry season and a positive correlation in the wet season, indicating that CH4 uptake occurred during the dry season. However, our results show that there is not a significant pattern of CH4 uptake (at a 95% confidence limit). Given the large discrepancy in the literature regarding CH4 uptake from agroforestry soils, further investigation of CH4 fluxes from agroforestry soils is warranted. Understanding CH4 fluxes in tropical agroforestry soils are of paramount importance for agroforestry utilization as a tool for climate change mitigation through the REDD+ program.

The Nutritional Lipid Profiles of Marine Fish from Medan, Indonesia

BACKGROUND: Evaluation of the nutritional value of fish is very important because fish contains essential fatty acids. Fatty acids substances in fish are very important for brain growth and the immune system of the fetus and baby, are also useful as cardioprotective, antihypertensive, anti-thrombolytic, cognitive development, fat metabolism, and anti-inflammatory. AIM: The aim of this research is to determine the nutritional index of marine fish based on the fatty acid composition that is circulated in Medan City. METHODS: Fish samples were collected from traditional markets; those is Thunnus spp., Lutjanus argentimaculatus, Sardina pilchardus, Rastrelliger kanagurta, and Euthynnus affinis. While, fish oil was produced from extracted with n-hexane and characterization by determining the acid, saponification, iodine, and peroxide value, respectively. The analysis of fatty acid composition was carried out by gas chromatography method. RESULTS: The result of research shows, the proportion of fatty acids in marine fish samples was saturated fatty acid (SFA) >monounsaturated fatty acid >polyunsaturated fatty acid. From the nutritional index based on fatty acid composition, the best nutritional fish is Thunnus spp. based on the index value of atherogenic index (IA) and hypocholesterolemic/hypercholesterolemic. CONCLUSION: As for the ratio of omega-6/omega-3, polyunsaturated/SFA (P/S), and thrombogenic index (IT), that is in the second rank category, so it can conclude that Thunnus sp. has the best nutritional index among the five types of marine fish.

Hemp seed-based food products as functional foods: A comprehensive characterization of secondary metabolites using liquid and gas chromatography methods

Despite hemp has a long history as food, in the last years the interest in cannabis cultivars, including new varieties, requires a deeper investigation of hemp seed-based food products as a precious source of biomolecules. In the present work, a comprehensive characterization of the minor components occurring in hemp seed-based food products i.e. oil, flour and flour by-product, is reported. For this goal, volatile (i.e. terpenes, hydrocarbons, furans and ketones) and non-volatile (i.e. tocopherols, cannabinoids and phenolic compound) metabolites were investigated by means of different chromatographic techniques. HPLC in combination with PDA, fluorescence, and MS detection was employed to analyse non-volatile fraction. Furthermore, GC coupled with FID and MS detectors were used for the analysis of volatiles and unsaponifiable compounds, the latters after conversion into more volatile trimethylsylil derivatives. Terpenes represented the most abundant compounds among volatiles. A total of 58 compounds belonging to the unsaponifiable matter was identified only in hempseed oils. Among tocopherols, γ-tocopherol was quantified at the highest level. Phenols and cannabinoids were also investigated, and a total of 52 compounds were identified and quantified. To the best of our knowledge, this is the first study providing a thorough chemical characterization of minor fraction of hemp products.

Molecular Liquids versus Ionic Liquids: The Interplay between Inter-Molecular and Intra-Molecular Hydrogen Bonding as Seen by Vaporisation Thermodynamics.

In this study, we determined the enthalpies of vaporisation for a suitable set of molecular and ionic liquids using modern techniques for vapour pressure measurements, such as the quartz crystal microbalance, thermogravimetric analysis (TGA), and gas chromatographic methods. This enabled us to measure reasonable vapour pressures, avoiding the problem of the decomposition of the ionic liquids at high temperatures. The enthalpies of vaporisation could be further analysed by applying the well-known "group contribution" methods for molecular liquids and the "centerpiece" method for ionic liquids. This combined approach allowed for the dissection of the enthalpies of vaporisation into different types of molecular interaction, including hydrogen bonding and the dispersion interaction in the liquid phase, without knowing the existing species in both the liquid and gas phases.

THE CONTENT OF SATURATED FATTY ACIDS IN THE BLOOD PLASMA OF GOATS DEPENDING ON THE TONE OF THE AUTONOMIC NERVOUS SYSTEM

Currently, goat breeding is actively moving to one of the first positions in the market of dairy and meat products. People are increasingly consuming goat's milk rather than cow's milk. Scientists are currently actively studying the factors affecting the content of fatty acids in the body of goats and in the milk they produce. Individual characteristics of each organism can be characterized as one of the most significant factors. The autonomic nervous system is one of the components of a number of systems in the adjustment of animal homeostasis. The purpose of the study is to establish the influence of the tone of the autonomic nervous system on the content of saturated fatty acids in the blood plasma of goats. Research was conducted on the basis of a private dairy farm in the village of Knyagininok, Lutsk district, Volyn region, goat breed – Zaanenskaya. Physiologically healthy 50 goats of 2-3 lactations were selected for variation-pulsometric research. The types of autonomous regulation were determined by determining the state of the cardiovascular system according to Baevsky. The content of saturated fatty acids in blood plasma lipids was determined by the method of gas chromatography with the study of the following fatty acids: butyric, caproic, caprylic, capric, lauric, myristic, pentadecanoic, palmitic, margaric, stearic, arachinic, tricosanoic acid. By comparing the obtained results, differences in the content of saturated fatty acids in blood plasma lipids of goats were established. It was established that the tone of the autonomic nervous system has an effect on the content of saturated fatty acids in the blood plasma of goats. It was determined that animals with a preference for the sympathetic nervous system have a lower content of saturated fatty acids (capric, myristic, pentadecanoic, palmitic, stearic, tricosanoic) in relation to other research groups (Р<0.05, Р<0.001). The experimental group of vagotonics has the highest content of saturated fatty acids (capric, myristic, pentadecanoic, palmitic, stearic, tricosanoic) in the blood plasma of goats (Р<0.05, Р<0.01, Р<0.001). The experimental group of normotonics occupied an intermediate place in terms of the content of saturated fatty acids in the lipids of the blood plasma of cows.

Relationship between refractive index and fatty acid composition by gas chromatography and near-infrared fiber-optic method in bovine fat.

The causes of the difference in fatty acid composition between gas chromatography (GC) and near-infrared fiber-optic method (NIR) in bovine fat and their countermeasures were studied using absolute values of refractive index. Using intermuscular fat from 45 crossbreeds, refractive index was measured by using a refractometer, and saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) were measured by NIR and GC. The correlation coefficients between GC and NIR in SFA and MUFA, as well as those between refractive index and GC or NIR (in SFA and MUFA), were all greater than or equal to 0.8 (p < 0.01). In samples with 3% or more difference between GC and NIR in SFA and MUFA, GC and NIR values were often located in opposite directions to the regression lines with regard to refractive index. GC reanalysis on these samples slightly increased the correlation coefficient between GC and refractive index and reduced the difference between GC and NIR by 1%-2%. Results indicate that measurement errors in GC and NIR are related to their more than 3% difference, and GC reanalysis based on refractive index may improve its accuracy.

Технология получения азотногелиевой смеси из природного газа месторождений Восточной Сибири

The article considers technological processes for obtaining helium. A basic technological scheme for obtaininga nitrogen-helium mixture from natural gas from the fields of Eastern Siberia is presented. The gas chromatographic method was used to study the component composition of the feed gas and the resulting nitrogen-helium mixture.A method for recycling the spent adsorbent containing metallic mercury is proposed.

Primeri ispitivanja energetskih transformatora nakon ispada iz pogona i loših rezultata hemijske analize uzorka ulja

Power transformers represent one of the most important components in terms of generation, transmission and distribution of electrical power. Precisely for this reason, it is necessary to pay some attention in terms of preventive electrical measurements that should be done in order to have an adequate insight into their condition, avoid unwanted breakdowns and thus ensure stable and reliable operation of the entire power system. However, there are situations when power transformers fail due to various factors. In such cases, depending on which protection has reacted and preemptively switched off the observed transformer, and especially in the case of an outage due to the differential protection of the transformer, it is necessary to carry out certain tests before possible reconnection in order to assess the reason for the outage and the continued ability of the transformer itself to work. Electrical tests should be preceded by sampling oil from the transformer (and/or gas and oil from the Buchholz relay) for chemical analysis by the gas chromatography method. The results of the chemical analysis of the oil sample can express doubts about possible irregularities that may be a problem for further normal operation of the transformer and such situations are followed by certain electrical tests whose results in most cases will give a better insight into the state of the transformer itself. This paper will give examples of the results of electrical measurements (most often insulation resistance and dielectric loss factor of windings, magnetizing currents and ohmic resistance of windings) made after power transformers were out of operation and measurements after bad results of chemical analysis of oil samples.

Production and Characterisation of a Novel Dasheen (Colocasia esculenta) Alcoholic Fermented Beverage

In this study, an alcoholic fermented beverage of acceptable quality characteristics was produced from two types of dasheen (Colocasia esculenta L. Schott) musts, A – boiled dasheen must and B – cooked dasheen with must, each at three total soluble solids (TSS) levels (18, 22 and 25 °Brix). Quality characteristics of pH, TSS, alcohol content, titratable acidity (TA), specific gravity (SG), and spectrophotometric, microbiological, and sensory evaluations were analysed in the fermented beverages. Fermentation caused pH, SG and TSS to decrease while simultaneously increased TA. Coliforms were not detected in any of the must and fermented beverage samples. The one-way ANOVA showed a significant difference (p&lt;0.05) when the fermented beverage from musts A and B was compared on the final quality parameters of pH, SG, TSS, TA, a* component and sensory attributes (appearance, colour, taste, and mouthfeel). The beverage made from batch A, 25 °Brix was consumer acceptable based on sensory and physicochemical analyses with a pH of 3.12, SG of 1.0053, TSS of 10.13 °Brix, TA (% citric acid) of 0.75% and an alcohol content of 14.00 and 12.52% using the hydrometer and gas chromatography methods respectively. For the spectrophotometric analysis, the absorbance at 420 nm wavelength was 0.246 while the L* a* b* colour indices were 88.59, 0.13, and 1.36 respectively. The overall results indicate that this product can be beneficial to the Caribbean food and beverage industries. Keywords: Dasheen (Colocasia esculenta), alcoholic fermentation, sensory attributes, colorimetry, spectrophotometry, gas chromatography-flame ionisation detector

IMPROVING METHODS FOR MONITORING BEARING UNITS OF ELECTRIC MOTORS IN REVERSE WATER SUPPLY SYSTEMS OF NUCLEAR POWER PLANTS

Ensuring the reliability and safety of nuclear power plants is an urgent task for the Ukrainian energy industry. Permanent circulation of mineral turbine oil is necessary for lubrication of friction surfaces in bearing units of electric motors of water pumping units in cooling systems. Monitoring its condition can indicate the presence of equipment defects under the influence of various factors. Increasing the reliability of oil-filled equipment of nuclear power plants can be achieved by determining the content of dissolved gases in turbine oils; additives “Ionol”; mechanical impurities with the determination of their type. The content of dissolved gases and additives “Ionol” in turbine oils was determined by gas chromatography methods. For turbine oil and a mixture of “water in turbine oil” the physico-chemical and thermophysical properties were investigated – density; flash point; kinematic viscosity; acid number; the content of mechanical impurities, water, additives “Ionol”. The dependences of the concentrations of dissolved gases in turbine oil and the “water in turbine oil” mixture on temperature, as well as the nature of the effect of acoustic cavitation on the kinematic viscosity of the oil and the generation of dissolved gases, have been studied. The aim of the work is to increase the reliability of power equipment of nuclear power plants by improving the control of the physicochemical and thermophysical properties of mineral turbine oil of the brand “Tp-30” of the circulation system for supplying bearing oils with electric motor units of water pumping units of reverse water supply of nuclear power plants.

Bacterial Degradation of PCB 70 and its Hydroxy Derivatives is an Environmentally Friendly Way to Destroy Pops

One of the problems of our time is the environmentally safe destruction of polychlorinated biphenyls (PCBs) and their hydroxylated derivatives. The aim of the study was to investigate the features and prospects of the decomposition of PCB 70 (2,5,3’,4’-tetrachlorobiphenyl) and hydroxylated chlorobiphenyls derived from it by Rhodococcus wratislaviensis strain CH628. As a result of the application of methods of periodic cultivation, gas chromatography and light spectrometry, it was found that the efficiency of destruction of PCB 70 1 g of cells of strain CH628 was 90 mg PCB/day, and the same indicator for a mixture consisting of hydroxy derivatives obtained from PCB 70 was 56 mg PCB/day. It was shown that the strain uses all components of the mixture of hydroxy-PCB 70 as a growth substrate, but with different degradation rates. When cultivated in a mineral medium with PCB 70 or a mixture of hydroxy-PCB 70, strain CH628 forms biofilms. The analysis of the obtained results shows that the use of the Rhodococcus wratislaviensis CH628 strain will make it possible to develop a technology for the environmentally safe destruction of PCB 70 and hydroxy-PCBs derived from it.

Conditions of formation and sources of fluids of the birthplace of barren residential quartz of hydrothermal-metamorphogenic-metasomatic and hydrothermal-metamorphogenic genesis (Middle and South Urals)

The paper considers the conditions of quartz formation of hydrothermal-metamorphogenic-metasomatic and hydrothermal-metamorphogenic genesis of deposits and manifestations of the Middle and Southern Urals based on the study of fluid inclusions by methods of thermobarogeochemistry, ion and gas chromatography. It is established that the studied quartz objects are formed in a wide temperature range, against the background of insignificant differences in pressure values. It is shown that the temperatures of mineral formation in deposits of hydrothermal-metamorphogenic-metasomatic genesis vary from 440-230 ° C at a pressure of 1.2-1.4 kbar. The formation of these veins occurred with the participation of K-Mg-Fe-chloride fluid with a salinity of 1.2-8.7 wt. % NaCl-eq., depleted Mg and Fe due to the deposition of magnesia-ferruginous carbonates. A typomorphic feature of hydrothermal-metamorphogenic-metasomatic quartz is the high values of boron associated with the placement of quartz veins among pegmatoids and the presence of boron-containing mineral inclusions on quartz-vein objects. Veins of hydrothermal-metamorphogenic genesis were formed when the crack system was filled with quartz with the participation of a substantially K-Na chloride fluid (0.2-15.5 wt. % NaCl-eq.), at homogenization temperatures of 435-335 ° C and a pressure of 1.3-2.3 kbar. In the composition of fluid inclusions of hydrothermal-metamorphogenic-metasomatic quartz, the sum of "harmful" components (H2O, CO2, CH4, Cl, B, Na, K, Mg and Li) is less than in hydrothermal-metamorphogenic quartz. The studied quartz deposits and veins were formed in the range of temperatures and pressures not higher than the green shale stage during several successive stages: the formation of quartz veins – in a more high-temperature hydrothermal stage, while subsequent changes in quartz veins occurred under the influence of metamorphism processes, with a decrease in temperature. Subsequent changes are associated with the appearance of fracturing, cataclysm and recrystallization of quartz bodies with a decrease in grain size.

Analytical methodologies for oxidized organic compounds in the atmosphere.

Oxidized compounds in the atmosphere can occur as emitted primary compounds or as secondary products when volatile emitted precursors react with various oxidants. Due to the presence of polar functional groups, their vapor pressures decrease, and they condense onto small particles. Thereby, they have an effect on climate change by the formation of clouds and scattering solar radiation. The particles and oxidized compounds themselves can cause serious health problems when inhaled. Therefore, it is of utmost importance to study oxidized compounds in the atmosphere. Much ongoing research is focused on the discovery of new oxidized substances and on the evaluation of their sources and factors influencing their formation. Monitoring biogenic and anthropogenic primary oxidized compounds or secondary oxidized products in chamber experiments or field campaigns is common. New discoveries have been reported, including various oxidized compounds and a new group of compounds called highly oxidized organic molecules (HOMs). Analytics of HOMs are mainly focused on chromatography and high-resolution mass spectrometry employing chemical ionization for identifying and quantifying compounds at low concentrations. Oxidized compounds can also be monitored by spectrophotometric methods in which the determinations of total amounts are based on functional groups. This review highlights recent findings on oxidized organic compounds in the atmosphere and analytical methodologies used for their detection and quantification. The discussion includes gas and liquid chromatographic methods, sampling, extraction, concentration, and derivatization procedures involved, as well as mass spectrometric and spectrophotometric methods.

Chemical Evaluation of Liquidambar styraciflua L. Fruits Extracts and Their Potential as Anticancer Drugs.

Liquidambar styraciflua L. is an aromatic species, popularly used in traditional Chinese medicine to treat diarrhea, dysentery, coughs, and skin sores. The present study was designed to investigate the chemical composition and biological potential of extracts obtained from the fruits of this plant. For the chemical evaluation, it was used mainly liquid and gas chromatography, plus NMR, and colorimetric methods. The aqueous extract (EA) originated two other fractions: an aqueous (P-EA) and an ethanolic (S-EA). The three extracts were composed of proteins, phenolic compounds, and carbohydrates in different proportions. The analyses showed that the polysaccharide extract (P-EA) contained pectic polysaccharides, such as acetylated and methyl esterified homogalacturonans together with arabinogalactan, while the fraction S-EA presented phenolic acids and terpenes such as gallic acid, protocathecuic acid, liquidambaric acid, combretastatin, and atractyloside A. EA, P-EA, and S-EA showed antioxidant activity, with IC50 values of 4.64 µg/mL, 16.45 µg/mL, and 3.67 µg/mL, respectively. The cytotoxicity followed the sequence S-EA &gt; EA &gt; P-EA, demonstrating that the toxic compounds were separated from the non-toxic ones by ethanol precipitation. While the fraction S-EA is very toxic to any cell line, the fraction P-EA is a promising candidate for studies against cancer due to its high toxicity to tumoral cells and low toxicity to normal cells.

Estimation of silage VOC emission impacts of surface-applied additives by GC-MS

Ensiling, the process of microbial acidification and preservation of wet forage for livestock feed that yields silage, produces a significant amount of volatile organic compounds (VOCs). Measurement of the chemical species involved, their emission to the atmosphere, environmental impacts, and economic losses to agricultural producers have been discussed in previous studies. Strategies for mitigation of silage VOC emission are limited and focus primarily on ensiling efficiency and silage additives at time of ensiling. However, one novel strategy employed by some producers to reduce airborne particulates, “wetting down” or applying water to rations at the feed bunk may also impact VOCs emission. We tested this method in parallel with several other chemical solutions with potential nutritional relevance for effects on VOC emission from silage. A headspace gas chromatography (GC) method was adapted for use with a paired mass spectrometer (MS) to profile silage. The effects on corn silage VOC emissions of surface-applied solutions across a range of pH, viscosity, and hydrophobicity were determined by GC-MS VOC headspace measurements. Surface-applied liquid additives included: water, citric acid, malic acid, molasses, sorghum syrup, yucca extract, seaweed extract, vegetable glycerine, olive oil, grape seed oil, and sunflower oil. Sample-to-sample variation among vials containing 5 g fresh weight (fw) silage collected from a bulked, homogenized silo sample was high, highlighting a need for sufficient replication. The most prevalent volatile acid in corn silage, acetic acid, made up the majority of observed VOCs. However, in total, eighteen VOCs were detected across all samples and the effects of treatments were assessed for each individually and for their sum as total VOC emission. Water applied to the surface of silage samples did not significantly alter VOC emissions as compared to silage alone for most VOCs. The largest observed significant effects were from the oil additives. Grape seed oil increased acetaldehyde and acetone values, while sunflower seed oil increased propionic acid and propyl acetate. Several treatments, including vegetable glycerine and seaweed extract, led to numerical decreases in VOC emissions and lower emission variability. More work is needed to understand interactions between silage VOC emissions and surface-applied mitigation strategies, including: constraining silage sample heterogeneity; investigation of the prevalence of oil-based feed additives and potential impacts on whole-farm VOC emissions; and in situ, on-farm measurements of VOC emission from treated piles.