Characterization of Key Aroma Compounds and Main Contributing Amino Acids in Hot-Pressed Oil Prepared from Various Peanut Varieties.

The production of peanut oil in the industrial sector necessitates the utilization of diverse raw materials to generate consistent batches with stable flavor profiles, thereby leading to an increased focus on understanding the correlation between raw materials and flavor characteristics. In this study, sensory evaluations, headspace solid-phase micro-extraction gas chromatography mass spectrometry (HS-SPME-GC-MS), odor activity value (OAV) calculations, and correlation analysis were employed to investigate the flavors and main contributing amino acids of hot-pressed oils derived from different peanut varieties. The results confirmed that the levels of alcohols, aldehydes, and heterocyclic compounds in peanut oil varied among nine different peanut varieties under identical processing conditions. The OAVs of 25 key aroma compounds, such as methylthiol, 3-ethyl-2,5-dimethylpyrazine, and 2,3-glutarone, exceeded a value of 1. The sensory evaluations and flavor content analysis demonstrated that pyrazines significantly influenced the flavor profile of the peanut oil. The concentrations of 11 amino acids showed a strong correlation with the levels of pyrazines. Notably, phenylalanine, lysine, glutamic acid, arginine, and isoleucine demonstrated significant associations with both pyrazine and nut flavors. These findings will provide valuable insights for enhancing the sensory attributes of peanut oil and selecting optimal raw peanuts for its production.

An Eco-Friendly RP-HPLC Method Development and Validation for Quantification of Favipiravir in Bulk and Tablet Dosage Form Followed by Forced Degradation Study.

In this work, an eco-friendly simple, precise reverse phase high-performance liquid chromatography (HPLC) method has been developed and validated for Favipiravir in bulk and tablet dosage form followed by its force degradation study. The proposed method was validated to obtain official requirements including stability, accuracy, precision, linearity, robustness and selectivity as per International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) Guidelines. The estimation was developed on C (18) column reversed-phase using the mobile phase composition as methanol:water (10:90 v/v). The flow rate was set as 1 ml/min, and the maximum absorption was observed at 323 nm using Shimadzu Photo Diode Array detector. The Favipiravir, drug showed a precise and good linearity at the concentration ranges of 10-50 µg/mL. The Revearse Phase High Perforance Liquid Chromatography assay showed the highest purity ranging from 99.90 to 100.02% for Favipiravir, tablet dosage form, and 100.15% was the mean percentage purity. The percent recovery was found within the acceptance limit of (98.6-100.0%). Intra- and inter-day precision studies of the method were less than the maximum allowable limit percentage of relative standard deviation ≤ 2.0. The Favipiravir retention time was found to be 5.00 min. To examine the stability of the drug, various forced degradation studies were conducted on Favipiravir Active Pharmaceutical Ingredient. The developed method was validated according to the ICH guidelines. A very quick, cost-effective, precise and accurate HPLC method for the determination of Favipiravir has been developed and validated in compliance with ICH guidance Q2.

Determination of phase-partitioning tracer candidates in production waters from oilfields based on solid-phase microextraction followed by gas chromatography-tandem mass spectrometry.

In the present document, we report the development of an analytical method consisting of a sequential direct-immersion/headspace solid-phase microextraction (DI-HS-SPME) followed by gas-phase chromatography and tandem mass spectrometry (GC-MS/MS) for simultaneous analysis of 4-chlorobenzyl alcohol, 2,6-dichlorobenzyl alcohol, 4-methoxybenzyl alcohol, 3,4-dimethoxybenzyl alcohol, pyridine, and 2,3-dimethylpyrazine in oilfield production waters. These compounds are under evaluation for use as phase-partitioning tracers in oil reservoirs. To the best of our knowledge, this is the first time SPME has been applied to the analysis of these compounds in production waters, or any other type of matrix where the compounds targeted are the base for a technical application. Relevant extraction parameters, such as the adsorbent phase of the fiber, direct immersion or headspace, addition of salt, temperature and time of extraction were investigated. The final optimal operation conditions consist on extracting 5 mL of sample at pH 9.0 with 1.8 g of NaCl with constant stirring during 5 minutes of DI-SPME followed by 15 minutes of HS-SPME at 70 °C using a DVB/CAR/PDMS (50/30 µm) fiber. The limits of quantification (LOQ), linearity, precision and accuracy of the method were evaluated. Analyses of the tracer compounds and recovery studies were also performed on production waters from 8 different oilfields of the Norwegian continental shelf. LOQs between 0.080 and 0.35 µg L-1 were obtained. The recovery yields of the method were consistently higher than 85% and RSDs less than 13%. None of the tracer compounds was found in the real samples processed, which is consistent with one of the requirements for an artificial tracer in an oilfield: absence or constant and low background in the traced fluid. The performance of the method developed, combined with its easiness to automate, introduce a new, accurate and cost-efficient technique to process the hundreds of samples required by an inter-well tracer test.

Unraveling the chemosensory characteristics of strong-aroma type Baijiu from different regions using comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry and descriptive sensory analysis.

Comprehensive 2D gas chromatography-time-of-flight mass spectrometry was combined with descriptive sensory analysis to elucidate the specificity of strong-aroma type Baijiu (Chinese liquor) from different regions, based on regionally distinct flavor characterized by chemical and sensory profiles. Numerous potential aroma compounds (262) were identified, among which 58 aroma compounds were significantly different between the samples from Sichuan and Jianghuai regions. Relationships between these potential aroma compounds and sensory attributes were investigated by partial least squares regression and network analysis. The compounds that dominantly contributed to the important sensory attributes were identified. The high pyrazines, furanoids, and carbonyls amounts contributed to the high intensities of the cellar, toasted, and grain aroma profiles of the Sichuan region samples, while the high ester and alcohol levels contributed to the fruity and floral aroma profiles of the Jianghuai region samples. This approach may have practical application in flavor characterization of other alcoholic beverages.

Impact of whey protein hydrolysates on the formation of 2,5-dimethylpyrazine in baked food products.

Peptides have been reported to serve as precursors in the generation of alkylpyrazines, key aroma compounds in heated foods. Most previous studies, concerned with the generation of pyrazines via the Maillard reaction, were conducted using model systems of varying complexities. However, the formation of pyrazines in real food systems has received less attention. The aim of this study was to investigate the impact of adding protein hydrolysates as precursors for the generation of alkylpyrazines in baked food products such as bread and cookies. Two whey protein hydrolysates, obtained using either trypsin or proteinase from Aspergillus melleus, were used in the presented study. 2,5-Dimethylpyrazine was produced in both food systems. Therefore, its formation was quantitatively monitored using a stable isotope dilution assay. Additionally, sensory evaluation was performed. Results demonstrated that the addition of the protein hydrolysates were effective in promoting the generation of 2,5-dimethylpyrazine and other aroma compounds in two well-known food products.

Headspace solid-phase microextraction coupled to gas chromatography-mass spectrometry with selected ion monitoring for the determination of four food flavoring compounds and its application in identifying artificially scented rice.

The adulteration of rice using synthetic aromatic flavorings to fraudulently imitate commercially valuable fragrant rice varieties has attracted extensive attention from regulatory authorities around the world. In order to get convincing evidence of adulteration, appropriate scientific analytical methods need to be developed. In this study, a simple and efficient headspace solid-phase microextraction (HS SPME) technique coupled with gas chromatography mass spectrometry using selected ion monitoring (GC-MS-SIM) for the determination of four food flavoring compounds which are possibly used as adulterants is proposed. The HS SPME operating under optimized conditions increased the selectivity and sensitivity of the analysis by eliminating matrix interferences. The method presented adequate precision and linearity with limits of detection ranging from 0.5 to 10 ng/mL. This HS SPME/GC-MS-SIM method is directly applicable to the analysis of volatiles in rice and has the advantages of minimal pretreatment. It was applied successfully to the analysis of six rice flavoring essences, ten fragrant rice and four artificially scented rice samples.

Characterization of the aroma release and perception of white bread during oral processing by gas chromatography-ion mobility spectrometry and temporal dominance of sensations analysis.

The purpose of this study was to investigate the aroma release and perception from white bread during oral processing by gas chromatography-ion mobility spectrometry (GC-IMS) and dynamic sensory evaluation of temporal dominance of sensations (TDS). TDS curves indicated that two maximum aroma perception signals, fermentation-like and flour-like attributes, were perceived at the beginning and swallowing, respectively. The fermentation-like, flour-like, and sour attributes were the 3 dominant aromas during oral processing. A total of 35 volatile compounds were detected in the mouth cavity during chewing white bread, 19 of them were confirmed and quantified by using the respective external standard. Based on PLSR analysis, 8 aroma compounds were predicted as potent odorants contributing to the aroma perception from chewing white bread. By application of odor activity values analysis and addition experiments, ethyl butanoate, butyl acetate, hexanal, 3-(methylthio)-propanal, 3-methylbutanal, and 2,3-butanedione were confirmed as the key odorants contributing to the aroma perception during chewing of white bread.

Identification of alkylpyrazines by gas chromatography mass spectrometry (GC-MS).

Pyrazines are an important group of natural products widely used as food additives and fragrants. Gas chromatography-mass spectrometry (GCMS) is the most widely applied analytical technique for characterization of alkylpyrazines. However, mass spectra of many positional isomers of alkylpyrazines are very similar. Consequently, an unambiguous identification of each positional isomer by spectral interpretation or database search protocols is practically unfeasible. In fact, there are many misidentifications in literature. To identify alkylpyrazines, chemists often resort to gas chromatographic retention indices (RIs). Although there are many compilations of retention indices of alkylpyrazines, these databases are often incomplete and the values reported are sometimes inconsistent. Herein, we present retention indices of fifty-six alkylpyrazines recorded on DB-1, ZB-5MS, DB-624, and ZB-WAXplus stationary phases, and compare them with those available in the NIST-2017 MS-RI database. Furthermore, we demonstrate how RI values can be used, together with mass spectral interpretations, to identify certain alkylpyrazines unambiguously.

Bioavailability, Biotransformation, and Excretion of the Covalent Bruton Tyrosine Kinase Inhibitor Acalabrutinib in Rats, Dogs, and Humans.

Acalabrutinib is a targeted, covalent inhibitor of Bruton tyrosine kinase (BTK) with a unique 2-butynamide warhead that has relatively lower reactivity than other marketed acrylamide covalent inhibitors. A human [14C] microtracer bioavailability study in healthy subjects revealed moderate intravenous clearance (39.4 l/h) and an absolute bioavailability of 25.3% ± 14.3% (n = 8). Absorption and elimination of acalabrutinib after a 100 mg [14C] microtracer acalabrutinib oral dose was rapid, with the maximum concentration reached in <1 hour and elimination half-life values of <2 hours. Low concentrations of radioactivity persisted longer in the blood cell fraction and a peripheral blood mononuclear cell subfraction (enriched in target BTK) relative to plasma. [14C]Acalabrutinib was metabolized to more than three dozen metabolites detectable by liquid chromatography-tandem mass spectrometry, with primary metabolism by CYP3A-mediated oxidation of the pyrrolidine ring, thiol conjugation of the butynamide warhead, and amide hydrolysis. A major active, circulating, pyrrolidine ring-opened metabolite, ACP-5862 (4-[8-amino-3-[4-(but-2-ynoylamino)butanoyl]imidazo[1,5-a]pyrazin-1-yl]-N-(2-pyridyl)benzamide), was produced by CYP3A oxidation.Novel enol thioethers from the 2-butynamide warhead arose from glutathione and/or cysteine Michael additions and were subject to hydrolysis to a ß-ketoamide. Total radioactivity recovery was 95.7% ± 4.6% (n = 6), with 12.0% of dose in urine and 83.5% in feces. Excretion and metabolism characteristics were generally similar in rats and dogs. Acalabrutinib's highly selective, covalent mechanism of action, coupled with rapid absorption and elimination, enables high and sustained BTK target occupancy after twice-daily administration.

The formation pattern of off-flavor compounds induced by water migration during the storage of sea cucumber peptide powders (SCPPs).

The formation pattern of off-flavor compounds induced by water migration in sea cucumber peptide powders (SCPPs) stored at 25 °C and 75% RH for 24 h and 80 days were investigated. Water migration characteristic of SCPPs was monitored by LF-NMR. The effect of water migration on structure and morphology were analyzed by SEM, CD, and FTIR, respectively. The antioxidant activity of SCPPs was detected by EPR. Volatiles generated from SCPPs were detected by P&T-GC-MS. The antioxidant activity of SCPPs declined and structure exhibited abnormalities during the storage. After 24 h of storage, kinds of aldehydes decreased and the content of alcohols increased obviously. After 80 days, (Z)-3,5-dimethyl-2-(1-propenyl)-pyrazine and 1,2-benzenedicarboxylic acid-bis(2-methylpropyl) ester were identified as the characteristic off-flavor. These off-flavor compounds were probably formed through Maillard reaction. esterification, and microbial metabolism. This study can provide a basis for further exploration of the off-flavor formation mechanism.

Effect of Roasting Temperatures on the Properties of Bitter Apricot (Armeniaca sibirica L.) Kernel Oil.

Volatile compounds and quality changes of bitter apricot (Armeniaca sibirica L.) kernel oil (AKO) with different roasting conditions were determined. Bitter apricot kernels were roasted at 120, 130, 140 and 150°C for 15 min. Unroasted bitter apricot kernel oil was used as the control. Quality indicators included color, acid value and peroxide value, fatty acids, total phenols and oxidative stability. Peroxide values of the tested oils were 0.46-0.82 meq/kg, acid values were 0.60-1.40 mg KOH/g, and total phenol contents were 54.1-71.5 µg GAE/g. Oleic acid was the major fatty acid, followed by linoleic, palmitic, stearic and palmitoleic acids. Roasting increased the oxidative stability of bitter AKO. Volatile compounds were tentatively identified and semi-quantified. Among the 53 volatiles identified, benzaldehyde and benzyl alcohol were the major components. These two aroma compounds increased significantly during roasting and contributed sweet and almond flavors. Pyrazines were also prevalent and significantly increased with roasting. Sensory evaluation showed that roasted, nutty, sweet and oily aromas increased as roasting temperature increased.Practical applications: Bitter apricot kernels cannot be consumed directly, thus it is potentially beneficial to find uses for them, especially in China where bitter apricot processing is a significant industry. Roasted bitter AKO with a pleasant aroma could be prepared and might find use as an edible oil. The roasting process gave the bitter AKO a pleasant flavor. This study provided preliminary information on production parameters and potential quality control parameters.

Development and validation of a sensitive LC MS/MS method for the measurement of the checkpoint kinase 1 inhibitor prexasertib and its application in a cerebral microdialysis study.

LC MS/MS methods to measure prexasertib in mouse plasma and Ringer's solution containing 0.5% BSA (Ringer's/BSA) were developed and validated. Liquid-liquid extraction with tert-butyl methyl ether was used to extract prexasertib from mouse plasma and Ringer's/BSA. Reverse phase chromatography with gradient elution was performed to separate prexasertib from the endogenous interference in the matrix, followed by MS detection using positive ion MRM mode. The initial calibration curve for mouse plasma samples ranged from 1 to 500 ng/ml, and after validation of that curve and use in a preliminary study another calibration curve (0.2-200 ng/ml) was created to enable the quantitation of prexasertib at lower concentrations. The method described was precise and accurate with %CV in precision studies of ≤ 6.7% and accuracies within 95.0-110% of nominal target concentration across all concentrations tested for both matrices. This validated method was successfully applied in the analysis of prexasertib in mouse plasma and dialysate samples collected during a cerebral microdialysis study.

Determination of ppq-levels of alkylmethoxypyrazines in wine by stirbar sorptive extraction combined with multidimensional gas chromatography-mass spectrometry.

Alkylmethoxypyrazines are powerful odorants in many food products. A new method for analysing 3-isopropyl-2-methoxypyrazine, 3-s-butyl-2-methoxypyrazine and 3-isobutyl-2-methoxypyrazine has been developed and applied to wine. The analytes were extracted from 5 mL of wine using stirbar sorptive extraction followed by thermal desorption and multidimensional gas chromatography-mass spectrometry analysis in a single oven. The extraction conditions were optimized in order to obtain a high recovery of the 3-alkyl-2-methoxypyrazines (MP). The detection limits of the method in all cases were under 0.08 ng/L, well below the olfactory thresholds of these compounds in wine. The reproducibility of the method was adequate (below 10%), the linearity satisfactory and the recoveries in all cases close to 100%. The method has been applied to the analysis of 111 Spanish and French wine samples. The levels found suggest that MP have a low direct impact on the aroma properties of wines from the regions around the Pyrenean massif.

Evolution of potent odorants within the volatile metabolome of high-quality hazelnuts (Corylus avellana L.): evaluation by comprehensive two-dimensional gas chromatography coupled with mass spectrometry.

Within the pattern of volatiles released by food products (volatilome), potent odorants are bio-active compounds that trigger aroma perception by activating a complex array of odor receptors (ORs) in the regio olfactoria. Their informative role is fundamental to select optimal post-harvest and storage conditions and preserve food sensory quality. This study addresses the volatile metabolome from high-quality hazelnuts (Corylus avellana L.) from the Ordu region (Turkey) and Tonda Romana from Italy, and investigates its evolution throughout the production chain (post-harvest, industrial storage, roasting) to find functional correlations between technological strategies and product quality. The volatile metabolome is analyzed by headspace solid-phase microextration combined with comprehensive two-dimensional gas chromatography and mass spectrometry. Dedicated pattern recognition, based on 2D data (targeted fingerprinting), is used to mine analytical outputs, while principal component analysis (PCA), Fisher ratio, hierarchical clustering, and analysis of variance are used to find decision makers among the most informative chemicals. Low-temperature drying (18-20 °C) has a decisive effect on quality; it correlates negatively with bacteria and mold metabolic activity, nut viability, and lipid oxidation products (2-methyl-1-propanol, 3-methyl-1-butanol, 2-ethyl-1-hexanol, 2-octanol, 1-octen-3-ol, hexanal, octanal and (E)-2-heptanal). Protective atmosphere storage (99% N2-1% O2) effectively limits lipid oxidation for 9-12 months after nut harvest. The combination of optimal drying and storage preserves the aroma potential; after roasting at different shelf-lives, key odorants responsible for malty and buttery (2- and 3-methylbutanal, 2,3-butanedione and 2,3-pentanedione), earthy (methylpyrazine, 2-ethyl-5-methyl pyrazine and 3-ethyl-2,5-dimethyl pyrazine) and caramel-like and musty notes (2,5-dimethyl-4-hydroxy-3(2H)-furanone - furaneol and acetyl pyrrole) show no significant variation. Graphical abstract Comprehensive two-dimensional gas chromatography (GC × GC) coupled with mass spectrometric detection captures hazelnut volatiles signatures while advanced fingerprinting approaches based on pattern recognition enable access to a higher level of information.

Accurate determination of 3-alkyl-2-methoxypyrazines in wines by gas chromatography quadrupole time-of-flight tandem mass spectrometry following solid-phase extraction and dispersive liquid-liquid microextraction.

A new reliable method for the determination 3-alkyl-2-methoxypyrazines (MPs) in wine samples based on the sequential combination of solid-phase extraction (SPE), dispersive liquid-liquid microextraction (DLLME) and gas chromatography (GC) quadrupole time-of-flight accurate tandem mass spectrometry (QTOF-MS/MS) is presented. Primary extraction of target analytes was carried out by using a reversed-phase Oasis HLB (200mg) SPE cartridge combined with acetonitrile as elution solvent. Afterwards, the SPE extract was submitted to DLLME concentration using 0.06mL carbon tetrachloride (CCl4) as extractant. Under final working conditions, sample concentration factors above 379 times and limits of quantification (LOQs) between 0.3 and 2.1ngL-1 were achieved. Moreover, the overall extraction efficiency of the method was unaffected by the particular characteristics of each wine; thus, accurate results (relative recoveries from 84 to 108% for samples spiked at concentrations from 5 to 25ngL-1) were obtained using matrix-matched standards, without using standard additions over every sample. Highly selective chromatographic records were achieved considering a mass window of 5mDa, centered in the quantification product ion corresponding to each compound. Twelve commercial wines, elaborated with grapes from different varieties and geographical origins, were processed with the optimized method. The 2-isobutyl-3-methoxypyrazine (IBMP) was determined at levels above the LOQs of the method in half of the samples.

Key odor and physicochemical characteristics of raw and roasted jicaro seeds (Crescentia alata K.H.B.).

Jicaro seeds (Crescentia alata) are widely consumed in Central America, primarily as a popular tasty and nutritious beverage called "horchata". Seeds are roasted to develop a specific aroma through a process that has never been explored. Volatile compounds, extracted from raw and roasted jicaro seeds (140°C for 140s) by SAFE (Solvent Assisted Flavor Evaporation), were analyzed by Gas Chromatography/Mass Spectrometry (GC/MS). Twenty-seven volatile compounds were isolated, among which, ethyl-2-methylbutyrate was designated by olfactometry as providing the characteristic jicaro note (0.16 and 0.47mg/kg dry basis (d.b.) in raw and roasted seeds, respectively). The release of volatile compounds from the Maillard reaction, such as pyrazines, and the increase of ethyl-2-methylbutyrate after roasting, exhausted the pleasant jicaro aroma. This mild roasting process had a slight impact on polyphenol, fructose and free amino acid contents, in agreement with the Maillard reaction. Confocal microscopy showed the coalescence of lipids in roasted jicaro seeds, which might explain the higher extracted fat content.

Evaluation of the antioxidant property and effects in Caenorhabditis elegans of Xiangxi flavor vinegar, a Hunan local traditional vinegar.

Xiangxi flavor vinegar (XV) is one of Hunan Province's traditional fermented vinegars. It is produced from herb, rice, and spring water with spontaneous liquid-state fermentation techniques. In this study, we investigated the antioxidant property of XV by analyzing its antioxidant compounds, its free radical scavenging property in vitro and in vivo, and its effects on antioxidant enzyme activity and apoptosis in Caenorhabditis elegans. The results showed that XV is rich in antioxidants. In particular, ligustrazine reached 6.431 µg/ml. The in vitro 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH•), hydroxyl radical (•OH), and superoxide anion radical (O2•-) scavenging rates of XV were 95.85%, 97.22%, and 63.33%, respectively. The reactive oxygen species (ROS) content in XV-treated C. elegans decreased significantly (P<0.01) compared to the control group. Glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT) activities were remarkably increased (P<0.01) in C. elegans after XV treatment. In addition, XV could upregulate CED-9 protein expression and downregulate CED-3 protein expression in C. elegans. These results prove that XV is rich in antioxidants and scavenges radicals in vitro efficiently. XV inhibits apoptosis in C. elegans probably by scavenging ROS and increasing the activities of its antioxidant enzymes.

Impact of Leaf Removal, Applied Before and After Flowering, on Anthocyanin, Tannin, and Methoxypyrazine Concentrations in 'Merlot' (Vitis vinifera L.) Grapes and Wines.

The development and accumulation of secondary metabolites in grapes determine wine color, taste, and aroma. This study aimed to investigate the effect of leaf removal before flowering, a practice recently introduced to reduce cluster compactness and Botrytis rot, on anthocyanin, tannin, and methoxypyrazine concentrations in 'Merlot' grapes and wines. Leaf removal before flowering was compared with leaf removal after flowering and an untreated control. No effects on tannin and anthocyanin concentrations in grapes were observed. Both treatments reduced levels of 3-isobutyl-2-methoxypyrazine (IBMP) in the grapes and the derived wines, although the after-flowering treatment did so to a greater degree in the fruit specifically. Leaf removal before flowering can be used to reduce cluster compactness, Botrytis rot, and grape and wine IBMP concentration and to improve wine color intensity but at the expense of cluster weight and vine yield. Leaf removal after flowering accomplishes essentially the same results without loss of yield.

Multimodality Imaging of Cancer Superoxide Anion Using the Small Molecule Coelenterazine.

PURPOSE: We evaluated the small molecule coelenterazine as a potential reporter of cancer-associated superoxide anion in cell culture and in mice. PROCEDURES: The superoxide anion concentrations of various cancer cell lines were quantified by coelenterazine chemiluminescence in vitro. Coelenteramide fluorescence was detected via flow cytometry and fluorescent microscopy. Coelenterazine was used for the in vivo detection of cancer-associated superoxide anion using the 4T1 breast adenocarcinoma mouse model. RESULTS: Various cell lines in culture demonstrated different superoxide anion concentrations, with a signal range of 3.15 ± 0.06 to 11.80 ± 0.24 times that of background. In addition to chemiluminescent detection of coelenterazine, we demonstrated fluorescent detection of coelenteramide within the cytoplasm of cells. 4T1 murine mammary adenocarcinoma tumors in mice demonstrated significantly higher 2.13 ± 0.19-fold coelenterazine-based chemiluminescence than that of surrounding normal tissues. CONCLUSIONS: Collectively, our results indicate that coelenterazine can be used to assay superoxide anion concentrations in cultured cancer cells and in tumors growing in mice.

Chemical Compositions and Aroma Evaluation of Volatile Oil from the Industrial Cultivation Medium of Enterococcus faecalis.

Enterococcus faecalis is one of the major lactic acid bacterium (LAB) species colonizing the intestines of animals and humans. The characteristic odor of the volatile oils obtained from both the liquid medium after incubation (MAI) and liquid medium before incubation (MBI) in the cultivation process of E. faecalis was investigated to determine the utility of the liquid medium. In total, fifty-six and thirty-two compounds were detected in the volatile oils from the MAI (MAI oil) and MBI (MBI oil), respectively. The principle components of MAI oil were 2,5-dimethylpyrazine (19.3%), phenylacetaldehyde (19.3%), and phenylethyl alcohol (9.3%). The aroma extract dilution analysis (AEDA) method was performed using gas chromatography-olfactometry (GC-O). The total number of aroma-active compounds identified in the volatile oil from MBI and MAI was thirteen compounds; in particular, 5-methyl-2-furanmethanol, phenylacetaldehyde, and phenylethyl alcohol were the most primary aroma-active compounds in MAI oil. These results imply that the industrial cultivation medium after incubation of E. faecalis may be utilized as a source of volatile oils.