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1.
Food Chem ; 458: 140207, 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38943959

ABSTRACT

False flax (Camelina sativa L.), known as camelina, is an ancient oil plant that has gathered renewed interest. In this study, a comprehensive analysis encompassing nontargeted volatilomics and targeted, quantitative metabolomics performed for cold-pressed oil and press cake and was integrated with sensory analysis of cold-pressed camelina oil and the effect of seed roasting was evaluated. Roasting in general resulted in the formation of 22 new volatile organic compounds (VOCs) in oil, while roasting at 140 and 180 °C resulted in the formation of 12 and 124 unique VOCs, respectively. Roasting notably influenced the profile of primary and secondary metabolites in both oil and press cakes, as well as volatilome and aroma of cold-pressed camelina oil. Many VOCs can be attributed to thermal degradation of primary and secondary metabolites. Roasting intensified the flavour of cold-pressed camelina oil, enhancing the perception of notes formed through the Maillard reaction.

2.
Nutr Res ; 127: 63-74, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38876040

ABSTRACT

Betaine supplementation is used by athletes, but its mechanism of action is still not fully understood. We hypothesized that betaine supplementation would increase betaine concentration and alter amino acid profiles in relation to MTHFR genotype and dose in physically active males. The study followed a randomized placebo-controlled cross-over design. Blood samples were collected before and after each supplementation period. Serum was analyzed for amino acid profile, homocysteine, betaine, choline, and trimethylamine N-oxide (TMAO) concentrations. For the washout analysis, only participants starting with betaine were included (n = 20). Statistical analysis revealed no differences in the amino acid profile after betaine supplementation. However, betaine concentration significantly increased after betaine supplementation (from 4.89 ± 1.59 µg/mL to 17.31 ± 9.21 µg/mL, P < .001), with a greater increase observed in MTHFR (C677T, rs180113) T-allele carriers compared to CC (P = .027). Betaine supplementation caused a decrease in homocysteine concentration (from 17.04 ± 4.13 µmol/L to 15.44 ± 3.48 µmol/L, P = .00005) and a non-significant increase in TMAO concentrations (from 0.27 ± 0.20 µg/ml to 0.44 ± 0.70 µg/ml, P = .053), but had no effect on choline concentrations. Serum betaine concentrations were not significantly different after the 21-day washout from the baseline values (baseline: 4.93 ± 1.87 µg/mL and after washout: 4.70 ± 1.70 µg/mL, P = 1.000). In conclusion, betaine supplementation increased betaine and decreased homocysteine concentrations, but did not affect the amino acid profile or choline concentrations in healthy active males. Betaine concentrations may be dependent on MTHFR genotype.

3.
Food Chem ; 439: 138093, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38043285

ABSTRACT

The displacement effect can be an issue for the quantitation of analytes with low affinity towards the extraction phase in solid-phase microextraction (SPME) for food samples that have low level of binding matrix or high level of hydrophobic compounds. In this communication, automated sequential SPME-GC-MS strategy was developed for addressing the displacement issue. The SPME thin film with PDMS coating was firstly used for the extraction of hydrophobic components in the sample which cause displacement and then SPME fiber with DVB/CAR/PDMS coating was applied in the second step for the extraction of the remain compounds. This new strategy was investigated by using 10 key food odorants as target analytes and tested in commercial beer samples. The results suggested that sequential SPME can decrease the displacement effect and improve the extraction efficiency for polar analytes.


Subject(s)
Odorants , Solid Phase Microextraction , Solid Phase Microextraction/methods , Gas Chromatography-Mass Spectrometry
4.
Molecules ; 28(24)2023 Dec 07.
Article in English | MEDLINE | ID: mdl-38138475

ABSTRACT

This review presents an outline of the application of the most popular sorbent-based methods in food analysis. Solid-phase extraction (SPE) is discussed based on the analyses of lipids, mycotoxins, pesticide residues, processing contaminants and flavor compounds, whereas solid-phase microextraction (SPME) is discussed having volatile and flavor compounds but also processing contaminants in mind. Apart from these two most popular methods, other techniques, such as stir bar sorptive extraction (SBSE), molecularly imprinted polymers (MIPs), high-capacity sorbent extraction (HCSE), and needle-trap devices (NTD), are outlined. Additionally, novel forms of sorbent-based extraction methods such as thin-film solid-phase microextraction (TF-SPME) are presented. The utility and challenges related to these techniques are discussed in this review. Finally, the directions and need for future studies are addressed.


Subject(s)
Food Analysis , Pesticide Residues , Food Analysis/methods , Solid Phase Microextraction/methods , Solid Phase Extraction , Molecularly Imprinted Polymers
5.
Metabolites ; 13(10)2023 Sep 30.
Article in English | MEDLINE | ID: mdl-37887370

ABSTRACT

The grain of 30 winter wheat cultivars differing in terms of their resistance to FHB (Fusarium head blight) was tested. The cultivars were grown in four variants of field trials established in a split-plot design: control without fungicides, chemical control of FHB with fungicides after Fusarium inoculation, Fusarium head inoculation, and organic cultivation. The profile of volatile compounds in grain samples was determined by mean headspace-solid phase microextraction and analyzed by gas chromatography time-of-flight mass spectroscopy. The identified volatile profile comprised 146 compounds belonging to 14 chemical groups. The lowest abundance of volatile organic compounds (VOCs) was found for the organic cultivation variant. The performed discriminant analysis facilitated the complete separation of grain for individual experimental variants based on the number of VOCs decreasing from 116 through 62, 37 down to 14. The grain from organic farming was characterized by a significantly different VOCs profile than the grain from the other variants of the experiment. The compounds 1-methylcycloheptanol, 2-heptanone, 2(3H)-furanone, and 5-hexyldihydro-2(3H)-furanone showed statistically significant differences between all four experimental variants.

6.
J Sci Food Agric ; 103(12): 6080-6094, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37144348

ABSTRACT

BACKGROUND: The present study aimed to demonstrate the superiority of bioethanol yield and its quality from sorghum using the granular starch degrading enzyme Stargen™ 002 over simultaneous saccharification and fermentation, and separate hydrolysis and fermentation using Zymomonas mobilis CCM 3881 and Ethanol Red® yeast. RESULTS: Bacteria were found to produce ethanol at higher yield than the yeast in all fermentations. The highest ethanol yield was obtained with Z. mobilis during 48 h of simultaneous saccharification and fermentation (83.85% theoretical yield) and fermentation with Stargen™ 002 (81.27% theoretical yield). Pre-liquefaction in fermentation with Stargen™ 002 did not improve ethanol yields for both Z. mobilis and Saccharomyces cerevisiae. Chromatographic analysis showed twice less total volatile compounds in distillates obtained after bacterial (3.29-5.54 g L-1 ) than after yeast (7.84-9.75 g L-1 ) fermentations. Distillates obtained after bacterial fermentation were characterized by high level of aldehydes (up to 65% of total volatiles) and distillates obtained after yeast fermentation of higher alcohols (up to 95% of total volatiles). The process of fermentation using granular starch hydrolyzing enzyme cocktail Stargen™ 002 resulted in low amounts of all volatile compounds in distillates obtained after bacterial fermentation, but the highest amounts in distillates obtained after yeast fermentation. CONCLUSION: The present study emphasizes the great potential of bioethanol production from sorghum with Z. mobilis using granular starch hydrolyzing enzyme Stargen™ 002, which leads to reduced water and energy consumption, especially when energy sources are strongly related to global climate change. © 2023 Society of Chemical Industry.


Subject(s)
Sorghum , Zymomonas , Saccharomyces cerevisiae , Ethanol , Fermentation , Starch
7.
J Agric Food Chem ; 71(5): 2637-2643, 2023 Feb 08.
Article in English | MEDLINE | ID: mdl-36701260

ABSTRACT

Mass spectrometry based quasi-electronic nose using solid-phase microextraction to introduce volatiles directly to mass spectrometer without chromatographic separation (HS-SPME-MS) was used to discriminate 45 raw spirits produced from C3 (potato, rye, wheat) and C4 (corn, sorghum) plants. The samples were also subjected to isotope ratio mass spectrometry (IRMS), which unequivocally distinguished C3 from C4 samples; however, no clear differentiation was observed for C3 samples. On the contrary, HS-SPME-MS, which uses unresolved volatile compounds "fingerprints" in a form of ions of a given m/z range and various intensities provided excellent sample classification and prediction after OPLS-DA data processing verified also by the artificial neural network (ANN).


Subject(s)
Volatile Organic Compounds , Gas Chromatography-Mass Spectrometry/methods , Volatile Organic Compounds/chemistry , Mass Spectrometry/methods , Isotopes/analysis , Alcoholic Beverages/analysis , Solid Phase Microextraction/methods
8.
Anal Bioanal Chem ; 415(13): 2523-2534, 2023 May.
Article in English | MEDLINE | ID: mdl-36567330

ABSTRACT

The aim of this study was to track changes in the volatilome of cold-pressed oil and press cakes obtained from roasted seeds and to combine it with the profile of non-volatile metabolites in a single study, in order to understand pathways of volatile organic compound (VOC) formation caused by thermal processing. Comprehensive two-dimensional gas chromatography-time of flight mass spectrometry was used for the analysis of VOCs in cold-pressed oils and corresponding press cakes obtained after roasting of seeds at 140 and 180 °C prior to pressing. Contents of primary metabolites (amino acids, saccharides, fatty acids) as well as selected secondary metabolites (glucosinolates, polyphenols) were determined, as many of them serve as precursors to volatile compounds formed especially in thermal reactions. After roasting, the formation of Maillard reaction products increased, which corresponded to the reduction of free amino acids and monosaccharides. Moreover, levels of the products of thermal oxidation of fatty acids, such as aldehydes and ketones, increased with the increasing temperature of roasting, although no significant changes were noted for fatty acids. Among sulphur-containing compounds, contents of the products and intermediates of methionine Strecker degradation increased significantly with the increasing temperature of roasting. Degradation of glucosinolates to nitriles occurred after thermal treatment. The results of this study confirmed that seed roasting before cold pressing has a significant effect on the volatiles, but also indicated roasting-induced changes in non-volatile metabolites of oil and press cake. Such an approach helps to understand metabolic changes occurring during rapeseed processing in cold-pressed oil production.


Subject(s)
Glucosinolates , Seeds , Fatty Acids/analysis , Gas Chromatography-Mass Spectrometry , Glucosinolates/analysis , Plant Oils/chemistry , Rapeseed Oil , Seeds/chemistry , Cold Temperature
9.
Molecules ; 27(18)2022 Sep 19.
Article in English | MEDLINE | ID: mdl-36144849

ABSTRACT

At the base of the food pyramid is vegetables, which should be consumed most often of all food products, especially in raw and unprocessed form. Vegetables and mushrooms are rich sources of bioactive compounds that can fulfill various functions in plants, starting from protection against herbivores and being natural insecticides to pro-health functions in human nutrition. Many of these compounds contain sulfur in their structure. From the point of view of food producers, it is extremely important to know that some of them have flavor properties. Volatile sulfur compounds are often potent odorants, and in many vegetables, belonging mainly to Brassicaeae and Allium (Amaryllidaceae), sulfur compounds determine their specific flavor. Interestingly, some of the pathways that form volatile sulfur compounds in vegetables are also found in selected edible mushrooms. The most important odor-active organosulfur compounds can be divided into isothiocyanates, nitriles, epithionitriles, thiols, sulfides, and polysulfides, as well as others, such as sulfur containing carbonyl compounds and esters, R-L-cysteine sulfoxides, and finally heterocyclic sulfur compounds found in shiitake mushrooms or truffles. This review paper summarizes their precursors and biosynthesis, as well as their sensory properties and changes in selected technological processes.


Subject(s)
Agaricales , Insecticides , Cysteine , Esters , Humans , Isothiocyanates/analysis , Nitriles/analysis , Odorants , Sulfhydryl Compounds , Sulfides , Sulfoxides , Sulfur , Sulfur Compounds/chemistry , Vegetables/chemistry
10.
Molecules ; 27(16)2022 Aug 11.
Article in English | MEDLINE | ID: mdl-36014366

ABSTRACT

The aim of this work was to study the possibility of using medicinal plants in combination with salt-containing raw materials from the Aral Sea region for cosmetic purposes. The chemical and mineralogical compositions of salts occurring in this region were studied for pharmacological and cosmetic purposes. The salt-containing raw materials were studied by X-ray diffraction (XRD), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The microflora of saline-containing raw materials and flora of the Zhaksy-Klych lake were studied. Fifty-six plant species were identified, of which 25% belong to the Asteraceae family, 32% were Poaceae, 22% were Amaranthaceae, and 21% were Tamaricaceae. Using the solid-phase microextraction (SPME) method and comprehensive two-dimensional gas chromatography−mass spectrometry, the composition of volatile compounds in such plant species as Artemisia alba L., Achilleamillifolium L., Eleagus commutate Bernh. Ex Rydb., Psoraleadrupacea Bunge, Artemisia cipa O. Vegd., Thymus vulgaris L., Morus alba L., Salvia pratensis L., Glycyrhizaglabra L., Tanacetum vulgare L., Polygonumaviculare L., Alhagipseudoalhagi Gagnebin and Peganumharmala L., chosen on the basis of their herbal components for future cosmetic products, was determined. In total, 187 different volatile compounds were found in the endemic plant species Glycyrrhizaglabra L., of which the following were dominant: 1,7-octadiene-3-, 2,6-dimethyl- with a peak area of 4.71%; caryophyllenes; bicyclo[7.2.0]4,11,11-trimethyl-8-methylene-, [1R-(1R*,4E,9S*)]­3.70%; bicyclo[2.2.1] heptane-2-1,7,7-trimethyl-,(1S)­3.46%; cyclohexanone, 5-methyl-2-(1-methylethyledene)-; 2-isopropyledene-5­2.97%; menthol; cyclohexanol, 5-methyl-2-(1-methylethyl)-; p-menthane-3-ol; menthol alcohol; and 2-isopropyl-5­2.08%. The remaining compounds were detected in amounts of less than 2.0%. Tests of seven cosmetic compositions developed on the basis of plant extracts and salt-containing raw materials revealed that three samples had a moisturizing effect. Launching the production of cosmetic products in the Aral region will not only reduce social tensions but also significantly improve the environmental situation in the region.


Subject(s)
Artemisia , Plants, Medicinal , Gas Chromatography-Mass Spectrometry/methods , Menthol , Plant Extracts/chemistry , Plants, Medicinal/chemistry
12.
Molecules ; 27(2)2022 Jan 14.
Article in English | MEDLINE | ID: mdl-35056815

ABSTRACT

The storage of plant samples as well as sample preparation for extraction have a significant impact on the profile of metabolites, however, these factors are often overlooked during experiments on vegetables or fruit. It was hypothesized that parameters such as sample storage (freezing) and sample pre-treatment methods, including the comminution technique or applied enzyme inhibition methods, could significantly influence the extracted volatile metabolome. Significant changes were observed in the volatile profile of broccoli florets frozen in liquid nitrogen at -20 °C. Those differences were mostly related to the concentration of nitriles and aldehydes. Confocal microscopy indicated some tissue deterioration in the case of slow freezing (-20 °C), whereas the structure of tissue, frozen in liquid nitrogen, was practically intact. Myrosinase activity assay proved that the enzyme remains active after freezing. No pH deviation was noted after sample storage - this parameter did not influence the activity of enzymes. Tissue fragmentation and enzyme-inhibition techniques applied prior to the extraction influenced both the qualitative and quantitative composition of the volatile metabolome of broccoli.


Subject(s)
Brassica/metabolism , Flowers/metabolism , Food Handling/methods , Freezing , Glycoside Hydrolases/metabolism , Metabolome , Volatile Organic Compounds/chemistry , Brassica/growth & development , Flowers/growth & development , Food Storage , Plant Extracts/metabolism , Plant Proteins/metabolism , Volatile Organic Compounds/analysis , Volatile Organic Compounds/metabolism
13.
J Agric Food Chem ; 69(41): 12270-12277, 2021 Oct 20.
Article in English | MEDLINE | ID: mdl-34609877

ABSTRACT

Volatile compounds of raw and cooked green kohlrabi were investigated using a sensomics approach. A total of 55 odor-active compounds were detected and identified in raw and cooked green kohlrabi using GC-O. Twenty-eight odor-active compounds with high flavor dilution (FD) factors ranging from 64 to 1024 were quantitated, and odor activity values (OAVs) were determined. Eight compounds showed high OAVs in raw and cooked kohlrabi: five sulfur compounds (dimethyl trisulfide, methyl 2-methyl-3-furyl disulfide, and three isothiocyanates (1-isothiocyanato-3-(methylsulfanyl)propane, benzyl isothiocyanate, and 1-isothiocyanato-4-(methylsulfanyl)butane)), two lipid oxidation products (1-octen-3-one and trans-4,5-epoxy-(2E)-dec-2-enal), and 2-isopropyl-3-methoxypyrazine. Among these, the sulfur compounds contributed most to the overall smell of the raw and cooked vegetables. The quantitation analysis indicates that the eight odorants are the backbone compounds for raw and cooked kohlrabi. The OAVs for the backbone compounds and also for minor odorants are clearly higher in raw kohlrabi than in the cooked one. Differences can be explained by the influence of the cooking process.


Subject(s)
Brassica , Volatile Organic Compounds , Cooking , Flavoring Agents , Gas Chromatography-Mass Spectrometry , Odorants/analysis , Smell , Volatile Organic Compounds/analysis
14.
Molecules ; 26(4)2021 Feb 08.
Article in English | MEDLINE | ID: mdl-33567568

ABSTRACT

Cold-pressed plant oils are of high interest to consumers due to their unique and interesting flavors. As they are usually only pressed at low temperatures and filtered, without further processing stages (as refining), they preserve their character that originates from the plant the oil was extracted from. Coriander cold pressed oil is gaining popularity as a novel product, obtained from its fruits/seeds; due to the high amount of terpenes, it has very characteristic flavor. A novel, vacuum-assisted sorbent extraction (VASE) method was used to extract terpenes from coriander cold pressed oil. Optimal parameters were determined. The profile of compounds extracted using VASE was compared with that of classic hydrodistillation method. Moreover, 17 monoterpene hydrocarbons and alcohols were identified with ß-linalool as the main compound, followed by α-pinene, γ-terpinene, camphor, sylvestrene, ß-pinene, and o-cymene. Differences were noted between profiles of terpenes after hydrodistillation and VASE extraction. For 8 out of 17 terpenes, VASE was used for their quantitative analysis. Regarding simplicity of the method, small sample requirement (200 mg) and short extraction time (5 min), VASE combined with GC/MS is well suited for characterization of terpenes in such matrix as plant oils.


Subject(s)
Food Handling , Oils, Volatile/chemistry , Plant Oils/chemistry , Terpenes/analysis , Terpenes/isolation & purification , Vacuum , Terpenes/chemistry , Volatilization
15.
Molecules ; 26(2)2021 Jan 08.
Article in English | MEDLINE | ID: mdl-33430033

ABSTRACT

Cold-pressed oils are highly valuable sources of unsaturated fatty acids which are prone to oxidation processes, resulting in the formation of lipid oxidation products, which may deteriorate the sensory quality of the produced oil. The aim of the study was to determine the main volatile compounds which differentiate examined oils and could be used as the markers of lipid oxidation in various oils. In the experiment, cold-pressed oils-brown flaxseed, golden flaxseed, hempseed, milk thistle, black cumin, pumpkin, white poppy seed, blue poppy seed, white sesame, black sesame and argan oils from raw and roasted kernels-were analyzed. To induce oxidative changes, an accelerate storage test was performed, and oils were kept at 60 °C for 0, 2, 4, 7 and 10 days. Volatile compound profiling was performed using SPME-GC-HRToFMS. Additionally, basic measurements such as fatty acid composition, peroxide value, scavenging activity and phenolic compound contents were carried out. Multivariate statistical analyses with volatile compound profiling allow us to differentiate oils in terms of plant variety, oxidation level and seed treatment before pressing. Comparing black cumin cold-pressed oil with other oils, significant differences in volatile compound profiles and scavenging activity were observed. Compounds that may serve as indicators of undergoing oxidation processes in flaxseed, poppy seed, milk thistle and hemp oils were determined.


Subject(s)
Antioxidants/chemistry , Plant Oils/chemistry , Seeds/chemistry , Volatile Organic Compounds/chemistry
16.
Biomolecules ; 11(2)2021 01 27.
Article in English | MEDLINE | ID: mdl-33514072

ABSTRACT

Eugenyl-ß-D-glucopyranoside, also referred to as Citrusin C, is a natural glucoside found among others in cloves, basil and cinnamon plants. Eugenol in a form of free aglycone is used in perfumeries, flavourings, essential oils and in medicinal products. Synthetic Citrusin C was incubated with human saliva in several in vitro models together with substrate-specific enzyme and antibiotics (clindamycin, ciprofloxacin, amoxicillin trihydrate and potassium clavulanate). Citrusin C was detected using liquid chromatography with tandem mass spectrometry (LC-MS/MS). Citrusin C was completely degraded only when incubated with substrate-specific A. niger glucosidase E.C 3.2.1.21 (control sample) and when incubated with human saliva (tested sample). The addition of antibiotics to the above-described experimental setting, stopped Citrusin C degradation, indicating microbiologic origin of hydrolysis observed. Our results demonstrate that Citrusin C is subjected to complete degradation by salivary/oral cavity microorganisms. Extrapolation of our results allows to state that in the human oral cavity, virtually all ß-D-glucosides would follow this type of hydrolysis. Additionally, a new method was developed for an in vivo rapid test of glucosidase activity in the human mouth on the tongue using fluorescein-di-ß-D-glucoside as substrate. The results presented in this study serve as a proof of concept for the hypothesis that microbial hydrolysis path of ß-D-glucosides begins immediately in the human mouth and releases the aglycone directly into the gastrointestinal tract.


Subject(s)
Fluorescein/chemistry , Glucosides/metabolism , Saliva/metabolism , Anti-Bacterial Agents/pharmacology , Chromatography, Liquid , Gastrointestinal Tract/metabolism , Glucosides/chemistry , Healthy Volunteers , Humans , Hydrolysis , In Vitro Techniques , Kefir , Kinetics , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Tandem Mass Spectrometry , beta-Glucosidase/metabolism
17.
J Chromatogr A ; 1636: 461774, 2021 Jan 11.
Article in English | MEDLINE | ID: mdl-33333375

ABSTRACT

Baijiu is a traditional Chinese spirit with an extraordinarily rich pattern of volatile compounds resulting from the microflora involved in fermentation, as well as the complexity of technological process. Comprehensive two-dimensional gas chromatography in the conventional and reversed column setups (non-polar - polar and polar - non-polar columns) was tested for its ability to differentiate Baijiu samples in terms of their aroma and origin (region). A total of 65 Baijiu samples were used for the study and volatile compounds were extracted by SPME with a subsequent analysis by GC×GC-TOFMS. Orthogonality of both setups was compared, so was the number of compounds identified using each setup. Repeatability of compound groups for the conventional and reversed column setups was compared; moreover, multiblock orthogonal component analysis (MOCA) was used to visualize data sets. OPLS-DA was used for Baijiu classification. Both column setups provided excellent discrimination of the Light, Soy sauce, Feng and Herbal aromas. A better classification result for the Strong and Jian aromas was recorded for the conventional column setup. Within the Strong aroma using OPLS-DA both column setups provided perfect abilities to discriminate Baijiu from the Sichuan, Heilongjiang and Jiangsu regions. Two validation methods were applied in the classification models - all the predictive abilities evaluated by the internal validation were further confirmed by the external validation.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Volatile Organic Compounds/analysis , Area Under Curve , Discriminant Analysis , Least-Squares Analysis , ROC Curve , Reproducibility of Results , Solid Phase Microextraction , Volatile Organic Compounds/isolation & purification
18.
Food Chem ; 337: 128002, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-32927226

ABSTRACT

Solid-phase microextraction - mass spectrometry (SPME-MS) and fast gas chromatography based electronic nose (GC-E-Nose) were used and compared for their suitability to distinguish Baijiu of various aroma types and geographical origin. Baijiu is a traditional Chinese distilled spirit produced with complex consortia of microorganisms, which results in very complex aroma compounds profiles. A total of 65 Baijiu samples representing 6 aromas were investigated. Strong aroma types from 3 regions were examined for their origin. Data acquired on two analytical systems were processed using uniform statistical approach. Data were pre-processed for multi-classification (OPLS-DA) models as well as for binary classification (PLS-DA) ones. Aroma and regional classification performed using OPLS-DA indicated that the approach based on SPME-MS had better fitness and prediction ability compared with GC-E-Nose. The total correct classification rate for SPME-MS was 94.44% for aroma and 100% for region, whereas for GC-E-Nose these values were 91.53% and 93.94% respectively.


Subject(s)
Odorants/analysis , Volatile Organic Compounds/analysis , China , Electronic Nose , Gas Chromatography-Mass Spectrometry/methods , Solid Phase Microextraction/methods , Volatile Organic Compounds/chemistry
19.
Molecules ; 25(19)2020 Sep 23.
Article in English | MEDLINE | ID: mdl-32977439

ABSTRACT

The glucosinolates which are specialized plant metabolites of Brassica vegetables are prone to hydrolysis catalyzed by an endogenous enzyme myrosinase (thioglycoside hydrolase, thioglucosidase) that exists in Brassica plant tissue causing volatile isothiocyanates release. Currently existing literature data on the inactivation of myrosinase is insufficient in particular for use in the analysis of volatile and odor compounds in vegetables rich in glucosinolates. In this study, the impact of different metal salts in effective inactivation of enzyme activity was investigated by solid-phase microextraction (SPME) and GC/MS system in aqueous samples and kohlrabi matrix. A saturated solution of calcium chloride which is commonly used to stop enzyme activity in plant tissue inactivates the myrosinase-glucosinolate system. However, even without the participation of myrosinase, it changes the reaction pathway towards nitrile formation. The model experiment shows that optimum efficiency in inhibition of the enzyme system shows iron(III) ions, silver ions, and anhydride sodium sulfate resulting in no volatile products derived from glucosinolates. However, in the kohlrabi matrix, the strongest enzyme inhibition effect was observed for silver salt resulting in no volatile products, also both anhydrous Na2SO4 and saturated CaCl2 solution seem to be useful inhibitors in flavor studies.


Subject(s)
Glycoside Hydrolases/metabolism , Metals/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Salts/chemistry , Seeds/chemistry , Sinapis/chemistry , Enzyme Activation/drug effects , Volatilization
20.
Article in English | MEDLINE | ID: mdl-32622152

ABSTRACT

The aim of this study was to compare fatty acid (FA) intake and status in postmenopausal women with or without metabolic syndrome (MetS). 131 women were recruited to a case-control study in 2016-2018 in Poznan, Poland. Dietary intake, anthropometric and biochemical measurements, FA level in red blood cells (RBCs), and FADS1 (rs174546) and FADS2 (rs3834458) genotypes were determined. Compared to women without MetS, those with MetS had lower levels of EPA, n-3, EPA/α-linolenic acid (ALA), EPA/AA, DHA/AA, EPA+DHA/AA, PUFA/saturated FA, PUFA/monounsaturated FA, and n-3/n-6 ratios in RBCs. Participants with at least one minor allele of each polymorphism had lower levels of EPA, and EPA/AA, and a higher level of DHA/EPA in RBCs than did women with major alleles. MetS is associated with lower levels FAs that have a protective effect on cardiometabolic health. FADS1 and FADS2 polymorphisms are associated with unfavorable FA and status EPA/AA in RBC contributes to MetS.


Subject(s)
Erythrocytes/metabolism , Fatty Acids, Omega-3/blood , Fatty Acids, Omega-6/blood , Metabolic Syndrome/blood , Postmenopause/blood , Aged , Delta-5 Fatty Acid Desaturase , Fatty Acid Desaturases/blood , Fatty Acid Desaturases/genetics , Female , Genotype , Humans , Metabolic Syndrome/genetics , Middle Aged , Postmenopause/genetics
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