Extraction Of Volatile Organic Compounds Research Articles

Mapping soil VOCs using three green sample extraction techniques and GC–MS

Sample preparation is a very crucial step prior to sample analysis. Three green adsorptive sample preparation micro-extraction techniques were investigated (smart solid-phase microextraction (SPME), high-capacity sorptive extraction (HiSorb), and stir bar sorptive extraction (SBSE)) for the determination of volatile organic compounds (VOCs) emitted from vineyard soil samples after method optimization. More specifically, the 95 μm Carbon Wide Range/Polydimethylsiloxane (CWR/PDMS) smart SPME fiber, CWR/PDMS HiSorb, and PDMS Twister micro-extraction tools were compared for their extraction capabilities. The headspace (HS)-SPME-gas chromatography-mass spectrometry (GC–MS) method was proved better for the extraction of VOCs from the vineyard soils due to shorter exposure time (45 min), its automation (use of a fully automated system compared to the other two), and the high sample throughput analysis. The validation of the HS-SPME-GC–MS method showed good linearity (R2 ≥ 0.9951) and limit of detection (LOD), whereas the limit of quantitation (LOQ) ranged from 0.04-3.65 μg/kg. Also, the repeatability and reproducibility of the results showed a relative standard deviation (RSD) lower than 4.73 %. A total number of 47 soil-derived VOCs were identified through the validated HS-SPME-GC–MS method, and 9 targeted VOCs were quantified with total average concentrations ranging from 0.14-28.07 µg/kg. Smart SPME fiber proved beneficial over the two other tools, highlighting the aspects of green chemistry

Attractiveness of Golden Hamster infected with Leishmania amazonensis (Kinetoplastida: Trypanosomatidae) to laboratory-reared Lutzomyia longipalpis (Diptera: Psychodidae)

Lutzomyia longipalpis is the primary vector of Leishmania infantum in the Americas and a permissive vector for Leishmania amazonensis. Previous studies showed that Leishmania infantum-infected hosts can release different volatile organic compounds (VOCs) compared with uninfected hosts, presenting a higher attractiveness to vectors. In this study, we aimed to evaluate a possible effect of L. amazonensis infection of golden hamsters in three parameters: attractiveness to Lu. longipalpis females; blood volume ingested by sand fly females; and VOCs released by the animals.. Attractiveness was measured indirectly by the number of Lu. longipalpis females that blood fed in each L. amazonensis-infected and uninfected animal. For VOCs extraction, solid phase micro extraction fibers were used, which were analyzed by gas chromatography-mass spectrometry. Behavioral trials did not show any effect of L. amazonensis infection on the attraction of sand flies nor difference on blood meal rates of Lu. longipalpis fed in both goups of hamsters. Additionally, there was no difference between the VOCs profiles of L. amazonensis-infected or uninfected hamsters.

Sustainable bio-based solid phase extraction adsorbent for the determination of various types of organic compounds.

A sustainable, bio-based, mesoporous material, Starbon A800, was explored for use as an adsorbent in solid phase extraction (SPE). A solution containing seven nitrosamines was first used as a standard to optimise conditions for extraction efficiency with Starbon A800. After optimising conditions, 25 compounds of varying polarity (terpenes, phenolics, pesticides, PAHs, amines, and nitrosamines) were extracted with SPE using either Starbon® A800, C18 or Porous Graphitic Carbon (PGC) as the adsorbent, for comparison purposes. At the same time, 3 different elution solvents (heptane, dichloromethane, and ethanol) were used for each type of adsorbent. Hansen solubility parameters can be used to choose an appropriate elution solvent for the selected SPE adsorbent. The best average SPE recoveries found for the 25 various compounds were 83%, 79%, and 65% using Starbon A800, PGC, and C18 adsorbents respectively and these had dichloromethane as the elution solvent. The identification and quantification of components was carried out using UV-visible spectroscopy, two-dimensional gas chromatography (GCxGC) with time of flight/mass spectrometry (TOF/MS) or a nitrogen chemiluminescence detector (NCD). The optimized method was successfully applied to extract volatile organic compounds from red wine and tap water using Starbon A800. Starbon A800 was shown to be a promising, low-cost, green, scalable, alternative adsorbent for the extraction of various types of organic compounds of a wide range of polarities using SPE.

Extraction of volatile organic compounds liberated upon filament extrusion by 3D pen and its comparison with a desktop 3D printer using solid-phase microextraction fiber and Arrow

Desktop 3D printers that operate by the fused deposition modeling (FDM) mechanism are known to release numerous hazardous volatile organic compounds (VOCs) during printing, including some with potential carcinogenic effects. Operating in a similar manner to FDM 3D printers, 3D pens have gained popularity recently from their ability to allow users to effortlessly draw in the air or create various 3D printed shapes while handling the device like a pen. In contrast to numerous modern 3D printers, 3D pens lack their own ventilation systems and are often used in settings with minimum airflow. Their operation makes users more vulnerable to VOC emissions, as the released VOCs are likely to be in the breathing zone. Consequently, monitoring VOCs released during the use of 3D pens is crucial. In this study, VOCs liberated while extruding acrylonitrile butadiene styrene (ABS) filaments from a 3D pen were measured by solid-phase microextraction (SPME) combined with gas chromatography/mass spectrometry (GC/MS). SPME was investigated using the traditional fiber and Arrow geometries with the DVB/Carbon WR/PDMS sorbent while four different brands of ABS filaments—Amazon Basics, Gizmodork, Mynt 3D, and Novamaker—were used with the 3D pen. Heatmap analysis showed differentiation among these brands based on the liberated VOCs. The nozzle temperature and printing speed were found to affect the number and amount of released VOCs. This study goes a step further and presents for the first time a comparison between 3D pen and a desktop 3D printer based on liberated VOCs. Interestingly, the findings reveal that the 3D pen releases a greater number and amount of VOCs compared to the printer. The amounts of liberated VOCs, as indicated by the corresponding chromatographic peak areas, were found to be 1.4 to 62.6 times higher for the 3D pen compared to the 3D printer when using SPME Arrow.

Development of a safety analysis method for volatile organic compounds using 2-phenoxyethanol as solvent

Indoor volatile organic compounds (VOCs) are usually sampled using active carbon samplers and subsequently analyzed using gas chromatography-mass spectrometry (GC-MS) to assess the exposure risk to workers. Therefore, selection of a suitable solvent for VOC extraction is crucial. However, reports on the use of 2-phenoxyethanol—known for its low vapor pressure and low toxicity—as a solvent for extracting VOCs from activated carbon are lacking. Here, we show that 2-phenoxyethanol is a suitable alternative solvent with low toxicity and can extract a wide variety of VOCs without overlapping with target VOCs on the gas chromatogram. The recoveries of 2-phenoxyethanol were 57% (styrene) to 83% (methyl n-butyl ketone), which were higher than those of CS2, acetone, and n-hexane at room temperature. The recoveries improved to 67% (styrene) to 102% (isopentyl acetate) under 50 °C. Optimization of the GC conditions showed that a viscosity delay time of 3 s was required to avoid producing bubbles in the injection syringes. We selected DB-HeavyWAX as a column because it could be heated above the boiling point of 2-phenoxyethanol (247 °C), allowing the removal of 2-phenoxyethanol from the column. This study contributes to the development of analysis methods for VOCs under safe operating conditions.

Optimization and validation for identification of volatile organic com-pounds released from Trogoderma variabile Ballion using headspace solid-phase microextraction and GC-FID/MS

Volatile organic compounds (VOC) emitted by Trogoderma variabile at different life stages (larvae, female and male) can help us to understand the chemical signals that are released by the beetle which can serve as biomarkers for diagnostic purpose. There are several factors that effect on the optimization of VOC extraction including, temperature, jar size, number of insects, duration of extraction, and gas chromatography (GC) conditions. This study used headspace solid phase microextraction (HS-SPME) fibre coupled with flame ionization detection (FID) and gas chromatography with mass spectrometry (GC-MS) to determine the optimal method for accurate, rapid and cost-effective extraction and identification of VOC from different life stages of T. variabile. The HS-SPME technique and the analytical conditions with GC and GCMS were optimized and validated for the determination of VOCs released from T. variabile. Selection of the number of insects was based on the height and the number of peaks. Results showed that 15 and 20 larvae and adults respectively gave the best number of peaks. Sixteen hours were optimized as the best extraction time for larvae and adults to get maximum number of emitted VOCs. The number of compound released from T.variabile different stages was 7, 9 and 11 for male, female and larvae respectively. Furthermore, some compounds were identified in all stages such as oxime-, methoxy-phenyl, 2(3H)-furanone, 5-ethyldihydro- and nonanal. Also, most of the compounds were significantly different in peak area between different life stages.

Identification, semi-quantification, and dynamics of volatile organic compounds during spontaneous fermentation of two cocoa varieties from northern Peru, using HS-SPME/GC-MS techniques

During spontaneous fermentation, an important process through which cocoa beans pass, volatile organic compounds (VOCs) and non-VOCs are generated and act as precursors of aromas and flavors that influence the chocolate. In the north of Peru, cocoas of different varieties and qualities are grown, and one of the most valued is the fine aroma native cocoa (Cacao Fino de Aroma (CFA)) compared with the Castro Naranjal 51 Collection (CCN-51) variety. In this investigation, the VOCs generated during the spontaneous fermentation of CFA and CCN-51 varieties, from the department of Amazonas, Peru, were analyzed. For the extraction of VOCs, the headspace (HS) and solid-phase microextraction (SPME) techniques were used, while gas chromatography coupled to a mass spectrophotometer (GC-MS) was employed for their subsequent separation and identification. The spontaneous fermentation process lasted for 156 h, and a total of 122 VOCs were identified in 2 varieties. The dynamics of 20 VOCs were assessed, and the principal component analysis of 22 VOCs was performed to compare the profiles of VOC of the 2 cocoa varieties. In conclusion, the CFA variety presented higher concentrations of floral, fruity, and sweet aromatic VOCs that positively influence the quality of the chocolate.

Purge-assisted solid phase microextraction based on activated carbon as a new technique for determination of odorous compounds in drinking water samples

The purge and trap method is widely used to extract volatile organic compounds from aqueous samples, but this method is time-consuming and analytes are difficult to desorb. Compared to purge and trap, solid phase microextraction (SPME) can desorbs analytes easily and quickly by inserting the fiber into the injection site of a gas chromatograph. However, other studies have demonstrated that the purge and trap method has a lower detection limits than SPME. This research aims to improve the efficiency of SPME by coupling it with purging by N2, named purge assisted SPME or PSPME as a novel technique for determination and quantification of trace amounts of odorous compounds (geosmin and 2-methylisoborneol) from water samples. The results showed that the extraction efficiency of PSPME has increased more than five times compared to normal SPME. Also, the optimal extraction time has decreased from 30 min to about 10 min.

Evaporation Temperature Alters Physicochemical Characteristics and Volatile Maillard Reaction Products of Non-Centrifugal Cane Sugar (NCS): Comparison of Polyethylene Membrane and Retronasal Aroma Simulator Techniques for the Extraction of Volatile Organic Compounds in NCS

Non-centrifugal cane sugar (NCS) is produced from sugarcane syrup via thermal evaporation. This study aimed to assess the effects of different temperatures during the evaporation process on the physicochemical characteristics and Maillard reaction products (MRPs) of NCS. Evaporation was tested at three final heating temperatures (120, 130, and 140 °C). The moisture content, water activity, L*a*b* color spaces, and ICUMSA (International Commission for Uniform Methods of Sugar Analysis) values of the NCS were determined. Volatile MRPs of NCS were extracted using polyethylene (PE) membrane and retronasal aroma simulator (RAS) techniques, and their components were measured using gas chromatography. A higher evaporation temperature produced NCS with less moisture content and water activity. However, it also led to a darker color, as indicated by lower L* (brightness) and b* (yellow) values in the color spaces. Additionally, higher evaporation temperatures resulted in greater ICUMSA values. Moreover, higher heating increased the amounts of volatile MRPs, such as 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one, 2-furanmethanol, 2-methylpyrazine, 2,5-dimethylpyrazine, and 2,6-dimethylpyrazine. Negative correlations were observed between moisture content, water activity, brightness, yellow color, and the total MRPs obtained by PE and RAS extractions. Additionally, positive and significant correlations were confirmed between ICUMSA values and most MRPs. Thus, the evaporation temperature alters the key physicochemical traits and volatile compounds of NCS, affecting its physical stability and flavor quality.

Polydimethylsiloxane-coated macroporous silica adsorbent in thermal desorption gas chromatography

Polydimethylsiloxane (PDMS)-coated macroporous silica (MPSi) particles were developed for the extraction of volatile organic compounds (VOCs) from air samples in thermal desorption-gas chromatographic analysis. The gas sample was collected by a gas sampling pump at 100 mL/min. Different amounts of PDMS coating were prepared, and the fundamental extraction and desorption performances were investigated using even numbered n-alkanes of C8–C28. The extraction efficiency increased by increasing PDMS coating, and the desorption efficiency showed more than 99% at a desorption temperature of 310°C for all the investigated adsorbents. This remarkable desorption performance showed a higher peak area of the analytes than that of the Tenax TA-packed thermal desorption tube, especially for higher molecular weight compounds. Furthermore, an activated carbon particle of Carbopack X was introduced on the latter side of the PDMS-MPSi to extract low-molecular weight compounds. This double-bed-type extraction tube showed a successful determination of a wide range of VOCs. The double-bed-type extraction tube was then applied to the extraction of VOCs related to sick building syndrome (SBS). The results for the extraction and desorption performances of the SBS-related VOCs were well agreed with that of alkanes, and the applicability of the extraction tube to the determination of other types of conventional VOCs were confirmed.

Monitoring the liberation of volatile organic compounds during fused deposition modeling three dimensional printing using solid-phase microextraction coupled to gas chromatography/mass spectrometry

Three-dimensional (3D) printers have gained tremendous popularity and are being widely used in offices, laboratories, and private homes. Fused deposition modeling (FDM) is among the most commonly used mechanisms by desktop 3D printers in indoor settings and relies on the extrusion and deposition of heated thermoplastic filaments, resulting in the liberation of volatile organic compounds (VOCs). With the growing use of 3D printers, concerns regarding human health have risen as the exposure to VOCs may cause adverse health effects. Therefore, it is important to monitor VOC liberation during printing and to correlate it to filament composition. In this study, VOCs liberated with a desktop printer were measured by solid-phase microextraction (SPME) combined with gas chromatography/mass spectrometry (GC/MS). SPME fibers featuring sorbent coatings of varied polarity were chosen for the extraction of VOCs liberated from acrylonitrile butadiene styrene (ABS), tough polylactic acid, and copolyester+ (CPE+) filaments. It was found that for all three filaments tested, longer print times resulted in a greater number of extracted VOCs. The ABS filament liberated the most VOCs while the CPE+ filaments liberated the fewest VOCs. Through the use of hierarchical cluster analysis and principal component analysis, filaments as well as fibers could be differentiated based on the liberated VOCs. This study demonstrates that SPME is a promising tool to sample and extract VOCs liberated during 3D printing under non-equilibrium conditions and can be used to aid in tentative identification of the VOCs when coupled to gas chromatography-mass spectrometry.

Combined EC/EO processes for treating goat cheese whey wastewater

The dairy industry is currently one of the most important industrial sectors in the world, and due to the high demand for products, is considered the largest source of industrial wastewater in the food sector. Whey wastewater is the most abundant liquid by-product and is characterized by a high concentration of organic load. Thus, the treatment of cheese whey wastewater before discharge is considered important. Therefore, the processes of electrocoagulation (EC), electrooxidation (EO), as well as their combination (EC/EO) have been purposefully used for the treatment of goat cheese wastewater. The main parameters (current density (mA/cm2), agitation (rpm), pH, and operating time (min)) affecting the removal efficiency of chemical oxygen demand (COD) were studied for each process. Whey effluent was treated under the optimal conditions of EC with aluminum electrodes, and EO with a boron-doped diamond electrode (BDD), removing 40.5% and 55.3% of COD, respectively. The combined use of EC/EO eliminated 82.4% of COD in a total time of 90 min. Total nitrogen (TN), chloride (Cl−), nitrate (NO3−), and phosphate (PO4−3) pollutants were also determined. The aroma profile of the raw substrate changed during the electrochemical processes. The determination of the volatile organic compounds (VOCs) in raw and treated (EC, EO, and EC/EO) goat whey wastewater was monitored using a thermal desorption unit followed by gas chromatography/mass spectrometry (TD-GC/MS) after extraction of VOCs using the HiSorb technique. Coupling electrochemical technologies increased odor emissions from goat cheese whey wastewater.

A Complete Pipeline for Untargeted Urinary Volatolomic Profiling with Sorptive Extraction and Dual Polar and Nonpolar Column Methodologies Coupled with Gas Chromatography Time-of-Flight Mass Spectrometry.

Volatolomics offers an opportunity for noninvasive detection and monitoring of human disease. While gas chromatography-mass spectrometry (GC-MS) remains the technique of choice for analyzing volatile organic compounds (VOCs), barriers to wider adoption in clinical practice still exist, including: sample preparation and introduction techniques, VOC extraction, throughput, volatolome coverage, biological interpretation, and quality control (QC). Therefore, we developed a complete pipeline for untargeted urinary volatolomic profiling. We optimized a novel extraction technique using HiSorb sorptive extraction, which exhibited high analytical performance and throughput. We achieved a broader VOC coverage by using HiSorb coupled with a set of complementary chromatographic methods and time-of-flight mass spectrometry. Furthermore, we developed a data preprocessing strategy by evaluating internal standard normalization, batch correction, and we adopted strict QC measures including removal of nonlinearly responding, irreproducible, or contaminated metabolic features, ensuring the acquisition of high-quality data. The applicability of this pipeline was evaluated in a clinical cohort consisting of pancreatic ductal adenocarcinoma (PDAC) patients (n = 28) and controls (n = 33), identifying four urinary candidate biomarkers (2-pentanone, hexanal, 3-hexanone, and p-cymene), which can successfully discriminate the cancer and noncancer subjects. This study presents an optimized, high-throughput, and quality-controlled pipeline for untargeted urinary volatolomic profiling. Use of the pipeline to discriminate PDAC from control subjects provides proof of principal of its clinical utility and potential for application in future biomarker discovery studies.

Improved sample storage, preparation and extraction of blueberry aroma volatile organic compounds for gas chromatography

Aroma profiles of blueberries contain a heterogeneous mixture of volatile organic compounds (VOCs), and headspace sampling is the most efficient approach to VOC extraction from berries. Typically, headspace solid-phase microextraction (HS-SPME) has been applied to blueberry VOCs. Though HS-SPME has been the most common choice for headspace sampling, the fiber chemistry introduces selectivity to the extraction: preferential sorption may skew aroma profiles. Dynamic headspace (DHS) is an attractive substitute for HS-SPME, given its improved sensitivity and lessened bias imparted due to extraction phase selectivity. DHS extractions tend to yield a larger number of compounds and require even less sample than HS-SPME. These two extraction techniques were applied to homogenized blueberries and extracts were subjected to analysis by comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC-TOFMS). Major chemical classes were identified with filtering scripts for GC×GC-TOFMS data. The HS-SPME and DHS methods were assessed for reproducibility and chemical diversity (i.e., recovered chemical classes).

Analysis of VOCs in Urine Samples Directed towards of Bladder Cancer Detection.

Bladder cancer is one of most common types of cancer diagnosed in the genitourinary tract. Typical tests are costly and characterized by low sensitivity, which contributes to a growing interest in volatile biomarkers. Head space solid phase microextraction (SPME) was applied for the extraction of volatile organic compounds from urine samples, and gas chromatography time of flight mass spectrometry (GC×GC TOF MS) was used for the separation and detection of urinary volatiles. A cohort of 40 adult patients with bladder cancer and 57 healthy persons was recruited. Different VOC profiles were obtained for urine samples taken from each group. Twelvecompounds were found only in the samples from theBC group.The proposed candidate biomarkers are butyrolactone; 2-methoxyphenol; 3-methoxy-5-methylphenol; 1-(2,6,6-trimethylcyclohexa-1,3-dien-1-yl)-2-buten-1-one; nootkatone and 1-(2,6,6-trimethyl-1-cyclohexenyl)-2-buten-1-one.Since most of the studies published in the field are proving the potential of VOCs detected in urine samples for the screening and discrimination of patients with bladder cancer from healthy, but rarely presenting the identity of proposed biomarkers, our study represents a novel approach.

Chemical Approach to the Optimization of Conditions Using HS-SPME/GC-MS for Characterization of Volatile Compounds in Eugenia brasiliensis Fruit.

Grumixama (Eugenia brasiliensis Lam.) is a native fruit of the Brazilian Atlantic Forest, belonging to the Myrtaceae family, which designatesthe most significant number of species with food potential. It stands out due to its phytochemical characteristics because of the presence of polyphenols and volatile organic compounds. Volatile compounds are substances released by foods that give off an aroma and influence flavor. Solid-phase microextraction is a technique that allows for low-cost, fast, and solvent-free extraction, has an affinity for numerous analytes, and is easily coupled to gas chromatography. The objectives of this work were to evaluate the efficiency of different fibers of SPME (solid-phase microextraction) in the extraction of volatile organic compounds from grumixama pulp; optimize a method for extraction time, temperature, and sample weight; and to determine the characteristic volatile profile of this fruit. For the extraction of volatile compounds, three fibers of different polarities were used: polar polyacrylate (PA) fibers, divinylbenzene/carboxyne/polydimethylsiloxane (DVB/CAR/PDMS) semipolar fibers, and polydimethylsiloxane/divinylbenzene (PDMS/DVB). Fourteen volatile organic compounds (VOCs) were identified by DVB/CAR/PDMS, six by PA, and seven by PDMS/DVB through solid-phase microextraction in the headspace mode (SPME-HS). Considering the total number of compounds identified, regardless of the fiber used, and the optimization of the method, Eugenia brasiliensis presented sesquiterpene fractions (85.7%, 83.3%, and 85.7% of total VOCs) higher than the monoterpene fractions (14.3%, 16.7%, and 14.3%) for DVB/CAR/PDMS, PA, and PDMS/DVB, respectively in its composition. In addition, it was possible to verify that the fiber DVB/CAR/PDMS presented a better efficiency due to the larger chromatographic area observed when the grumixama pulp was subjected to conditions of 75 °C, 2.0 g, and an adsorption time of 20 min.

Time Depletion Effects on the Volatile Compounds from the Distillation Extracts of Prunella vulgaris and the Dynamics of their Extraction.

Prunella vulgaris (PV) is a low-growing perennial herb, which can be found in different parts of the world as Asia, Europe and North America. It is traditionally used for medicinal treatment in various cultures in India, China, Japan, Korea, Russia, and Eastern Europe for treating different ailments, such as fever, and healing wounds. In our previous article, we showed the anti-tumorous effect of the volatile organic compounds (VOCs) of PV and characterized the steam distillation process in the extraction of VOCs from PV. This has never been done before as we are aware of. To use the VOCs as drugs, there is a question of how much of the VOCs are lost before the prepared drugs reach the patients. Thus, the first aim of the present article is to try to explore the time depletion effect on the VOCs in the PV extracts. Then, the second aim is to extend the work in the previous paper and further understand the dynamics of the distillation process of PV by changing the steam flow rate in the extraction process. To achieve the first aim to explore the aging effect of how much VOCs are depleted after they are extracted, the VOCs were first extracted by the same method as before, i.e., using steam distillation. Then, tubes of the aqueous solution containing the VOCs were then stored in a 5°C refrigerator. They were then taken out for GC-MS analysis according to a preplanned schedule up to 8 weeks after the VOCs were extracted. The chemical composition of the distillate could then be evaluated. This revealed the changes in the abundance of VOCs with aging. At the same time, the cell viability of SCC154 oral squamous cells treated by these herbal solutions, which were at different aging stages, was evaluated using a tetrazolium-based colorimetric reagent, Cell Counting Kit-8. To achieve the second aim of exploring the dynamics of the steam distillation process, the steam flow rate was adjusted by changing the temperature setting of the hot plate. GC-MS was again used to quantify the chemical constituents of the distillates. By using GC-MS to measure the abundance of volatile compounds at different time points after the distillation process, it was found that the volatile compounds persist for a very long time, or over 8 weeks, which was the longest period of our experiment. The aging of the distillates also did not depreciate much the cell cytotoxicity of the PV distillate on the cancer cells. With respect to the dynamics of the steam distillation process, it was found that, at a low steam flow rate, volatile compounds of lower molecular weight are more efficient to be extracted, while at a high steam flow rate, volatile compounds of higher molecular weight are more efficiently extracted. Our findings demonstrate that the VOC compounds extracted and present in aqueous form do not deplete much for at least 2 months after the extraction process, neither they exhibit cell cytotoxicity. The experiments on the dynamics of the steam distillation process demonstrate that the mass of herb present in the flow path of the steam has significant effects on the relative amounts of VOCs extracted.

Solvent-Free Microwave-Assisted Extraction of Volatile Organic Compounds from Ananas comosus (Pineapple) Waste and Possible Skincare Products Development

Solvent-Free Microwave-Assisted Extraction (SFME) is a green analytical technique that uses no organic solvent in the extraction process. A significant amount of fruit waste such as seeds, rinds and peels are discarded daily by food processing operations, causing many environmental concerns. As an alternative approach to fruit-specific waste minimization, including pineapple waste, those fruit waste can be used to recover potentially valuable Volatile Organic Compounds (VOCs) to utilize as value-added products. This study aims to extract VOCs from different parts of matured pineapple fruit waste, including core and peel, for skincare products development. This process uses SFME to extract VOCs from pineapple waste. Extractions were performed at three different experimental conditions by varying microwave power and extraction time of 300 W for 15 min, 500 W for 10 min, and 700 W for 5 min, respectively. The highest yield of 47.20% was obtained for the extraction performed with 500 W power and 10 min extraction time. Volatile Organic Compounds extracted by SFME were identified and characterized using gas chromatography-mass spectroscopy (GC/MS). Major VOCs extracted from the pineapple waste include Heptadecane, γ-dodecalactone, Hexadecane, γ-decalactone and Decanal. However, the highest VOCs were found in the pineapple core over the peel. Extracted VOCs were used to formulate a moisturizing cream and tested for its organoleptic properties, pH and spreadability. Result suggests favourable organoleptic properties such as white to off-white, non-greasy and no phase separation. The formulated moisturizing cream was able to retain the pH of 6.32±0.01 at the temperature of 27±2 ℃, and the spreadability of 4.76±0.11. Findings of the study reveal that SFME extracted VOCs of pineapple waste show promising potential in natural skincare products development.
 Keywords: Pineapple waste, Volatile Organic Compounds, Solvent-free Microwave-Assisted Extraction, GC-MS, Moisturizing cream

A simple sampling method for quantification of hazardous volatile organic compounds in mainstream cigarette smoke: Method development and prestudy validation

Cigarette smoke can be fatal to human health, as it contains a plethora of hazardous compounds such as volatile organic compounds (VOCs). To assess the toxic effects of cigarette smoke, both qualitative and quantitative information about the VOCs in cigarette smoke are essential. However, sampling and analysis of cigarette smoke are not simple tasks and require complicated validation procedures. Here, we develop and verify a simple sampling method for the quantification of VOCs in mainstream cigarette smoke using three steps: direct collection of the mainstream cigarette smoke sample by gas-tight syringe, injection of the sample into a bag sampler for dilution, and extraction of VOCs into an adsorption-tube sampler for quantitation by thermal desorption-gas chromatography-mass spectrometry. This method has been employed successfully to quantify seven target VOCs (isoprene, methyl ethyl ketone, benzene, acrylonitrile, toluene, m-xylene, and styrene) in cigarette smoke from 3R4F reference cigarettes. The quantities of these major five VOCs (isoprene, methyl ethyl ketone, benzene, acrylonitrile, and toluene: average of 459 ± 646 ng mL−1), when measured from 3R4F samples based on our method, were comparable to or moderately higher than those measured based on the established standard methods (e.g., Health Canada Intense (462 ± 557 ng mL−1) and International Standardization Organization (356 ± 438 ng mL−1)). As such, we succeeded in reliably collecting and quantifying VOCs in cigarette smoke using a simple sampling method proposed in this research. The proposed method is thus recommended as an alternative to complicated and costly representative methods based on international guidelines.

Comparison of Extraction Techniques for the Determination of Volatile Organic Compounds in Liverwort Samples.

This article focuses on the comparison of four popular techniques for the extraction of volatile organic compounds (VOCs) from liverworts of the Calypogeia azurea species. Since extraction is the most important step in the sample analysis of ingredients present in botanical preparations, their strengths, and weaknesses are discussed. In order to determine the VOCs present in plants, selecting the appropriate one is a key step of the extraction technique. Extraction should ensure the isolation of all components present in the oily bodies of Calypogeia azurea without the formation of any artifacts during treatment. The best extraction method should yield the determined compounds in detectable amounts. Hydrodistillation (HD), applying Deryng apparatus and solid-liquid extraction (SLE), microwave-assisted extraction (MAE), and headspace solid-phase microextraction (HS-SPME) were used for volatile extraction. The extracts obtained were analysed by gas chromatography coupled to mass spectrometry (GC-MS) to determine the compounds.