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Efforts are currently directed towards improving the quality of vegetables after freezing and thawing. One of the methods under investigation is isochoric freezing. In this study, we evaluated isochoric freezing for preserving the quality of baby‐leaf spinach. We compared the properties of thawed spinach frozen to −4°C in an isochoric system with those of fresh spinach, thawed spinach frozen to −4°C in an isobaric system and thawed spinach that were commercially frozen. Spinach leaves frozen under isobaric conditions lost mass and thickness, making them softer and translucent. They also lost much of their nutrient content. In comparison, isochoric freezing maintained cell integrity and turgidity. Thawed leaves remained crunchy with characteristics similar to fresh leaves. Isochoric freezing also preserved nutritional content better than isobaric freezing, although significant nutrient losses still occurred.

Methylenecyclcopropylglycine (MCPG) and hypoglycin A (HGA) are naturally occurring amino acids found in various soapberry (Sapindaceae) fruits. These toxins have been linked to illnesses worldwide and were recently implicated in Asian outbreaks of acute hypoglycemic encephalopathy. In a previous joint agricultural and public health investigation, we developed an analytical method capable of evaluating MCPG and HGA concentrations in soapberry fruit arils as well as a clinical method for the urinary metabolites of the toxins. Since the initial soapberry method only analyzed the aril portion of the fruit, we present here the extension of the method to include the fruit seed matrix. This work is the first method to quantitate both MCPG and HGA concentrations in the seeds of soapberry fruit, including those collected during a public health investigation. Further, this is the first quantitation of HGA in litchi seeds as well as both toxins in mamoncillo and longan seeds.

Methylenecyclopropylglycine (MCPG) and hypoglycin A (HGA) are naturally occurring amino acids found in some soapberry fruits. Fatalities have been reported worldwide as a result of HGA ingestion, and exposure to MCPG has been implicated recently in the Asian outbreaks of hypoglycemic encephalopathy. In response to an outbreak linked to soapberry ingestion, the authors developed the first method to simultaneously quantify MCPG and HGA in soapberry fruits from 1 to 10 000 ppm of both toxins in dried fruit aril. Further, this is the first report of HGA in litchi, longan, and mamoncillo arils. This method is presented to specifically address the laboratory needs of public-health investigators in the hypoglycemic encephalitis outbreaks linked to soapberry fruit ingestion.

In Amazonian Peru, the neotropical tree Protium subserratum Engl. (Burseraceae) occurs as distinct ecotypes on low nutrient white-sand (WS), intermediate fertility brown-sand (BS), and nutrient-rich clay (CS) soils. Genetic analysis indicates that these ecotypes are undergoing incipient speciation. Possible drivers of this divergence are habitat-specific herbivore faunas and differing resource availabilities. Protium subserratum, therefore, provides an ideal opportunity to investigate how defense chemistry evolves during lineage divergence. WS and BS races of P. subserratum are host to largely non-overlapping herbivore communities and they differ in chlorogenic acid, flavonoid, and oxidized terpene chemistry. Here, we investigate how another important class of anti-herbivore chemicals, procyanidins (PCs), varies among the ecotypes. We isolated the PCs from leaves of juvenile and adult trees from each ecotype and used spectroscopic and chemical techniques to characterize the chemical structures of their component monomers. We found that WS, BS, and CS ecotypes accumulate ca. 17 % of leaf dry weight as PCs. Within ecotypes, we found very little difference in PC type, neither by site nor by life stage. Among ecotypes, however, we observed a marked divergence in PC composition that arose at least in part from differences in their terminal and extension subunits. In addition, the average polymer length of BS and CS PCs was significantly greater than in WS ecotypes. We conclude that phenotypic differences in PCs in the WS versus BS and CS ecotypes of P. subserratum are consistent with selection by herbivores in different soil types that differ strongly in nutrient availability and may contribute to the evolution of habitat specialization.

Volatile constituents of commercial black-ripe table olives (Olea europaea) from the United States, Spain, Egypt and Morocco were analysed by gas chromatography and gas chromatography-mass spectrometry (GC-MS). Dynamic headspace sampling was used to isolate a variety of aldehydes, alcohols, esters, ketones, phenols, terpenes, norisoprenoids, and pyridines. Odour unit values, calculated from concentration and odour threshold data, indicate that the following compounds are major contributors to black-ripe table olive aroma: β-damascenone, nonanal, (E)-dec-2-enal, 3-methylbutanal, ethyl benzoate, octanal, 2-methoxyphenol, 2-methylbutanal and 2-methoxy-4-methylphenol. Imported olives contained a variety of fermentation derived volatiles that were not detected in domestic olives. Constituents such as ethyl 2-methylbutanoate, ethyl 3-methylbutanoate, 3-methylbutyl acetate, oct-1-en-3-one, ethyl hexanoate, (Z)-hex-3-enyl acetate, hexyl acetate, ethyl cyclohexanecarboxylate, benzyl acetate and 4-ethylphenol contributed to the odour of imported olives but were not detected in domestic olives.

Flour from the mesocarp of pods of the tree legume known as mesquite (Prosopis spp.) in North America or algarrobo in South America was one of the most important food staples for desert people. Contemporary milling techniques produce a flour similar to that of indigenous peoples that is about 40% sucrose, 25% dietary fiber, and that has a variety of volatiles, such as 2,6-dimethylpyrazine, γ-nonalactone, methyl salicylate, and 5,6-dihydro-6-propyl-2H-pyran-2-one, that contribute to a chocolate and coconut-like aroma. Flour made from the mesocarp contains no stachyose or raffinose, sugars that are responsible for flatulence in other legumes. High-performance liquid chromatography (HPLC) analyses of sugar (sucrose) and citric, malic, and ascorbic acids found considerable ranges in acid/sugar ratio that may be responsible for the wide variations in organoleptic perception. Due to the absence of gliadin, peanut, and soy allergens, the flour is useful in gluten-free formulations. Optimum concentrations for inc...

Summary Antioxidant activity (ABTS assay), total phenolics and total anthocyanins were determined in the petioles of twenty-nine rhubarb (Rheum spp.) varieties. Antioxidant activity ranged from 463 ± 50 (Rheum officinale) to 1242 ± 2 μmol Trolox per g DW (Valentine). The phenolic content varied from 673 ± 41 (Loher Blut) to 4173 ± 23 mg GAE/100 g DW (Plum Hutt) and had a low correlation (r = 0.663) with antioxidant results. Seven of the varieties (Plum Hutt, Valentine, Minnesota No. 8, Cherry Red, Cawood Delight, Coulter McDonald and OR 23) had higher total phenolics than kale, a vegetable rich in phenolics. The concentration of anthocyanins ranged from 19.8 ± 1.5 (Crimson Red) to 341.1 ± 41.6 mg/100 g DW (Valentine). The percentages of two main anthocyanins in rhubarb, cyanidin 3-glucoside and cyanidin 3-rutinoside varied from 66.07:33.93, respectively, in Valentine to 9.36:90.64, respectively, in R. officinale.

Volatile constituents of the aerial parts of fresh white sage (Salvia apiana Jepson) were isolated by extraction with diethyl ether followed by high vacuum distillation with a solvent assisted favor evaporation (SAFE) apparatus. The isolated volatiles were analyzed by GC and GC/MS. A total of 84 constituents were identifed (constituting 95.1% of the total area), 11 of which were tentatively identifed. The volatiles were characterized by a high content of hydrocarbon and oxygenated monoterpenes. The major constituents identifed were 1,8-cineole (34.5%), camphor (21.7%), β-pinene (7.4%), α-pinene (6.4%), δ-3-carene (6.4%), camphene (3.9%), limonene (3.5%), myrcene (3.2%), and terpinolene (1.3%).

Volatile constituents of Baikal skullcap (Scutellaria baicalensis Georgi) flowers were isolated by solid-phase microextraction (SPME) and analyzed by GC and GC-MS. A total of 64 constituents was identified (constituting 57.1 - 89.9 % of the total area), 13 of which were tentatively identified. β-Caryophyllene (22.3 - 41.5 %), germacrene D (12.4 - 27.5 %), δ-cadinene (3.1 - 5.4 %), γ-muurolene (1.9 - 3.4 %), γ-cadinene (1.6 - 3.1 %), α-humulene (1.6 - 2.6 %), α-copaene (1.4 - 2.3 %), α-muurolene (1.0 - 2.6 %), bicyclogermacrene (1.1 - 2.1 %) and 3-octanone (0.9 - 3.0 %) were the major constituents of the flower volatiles. A small amount (0.5 %) of the uncommon volatile, 2-(methylamino) benzaldehyde was detected in one of the samples.

The inhibitory activity of Curcuma longa L. (turmeric) rhizome constituents against sortase A, a bacterial surface protein anchoring transpeptidase, from Staphylococcus aureus ATCC 6538p was evaluated. The activity of the isolated compounds (1-4) was compared to that of the positive control,p-hydroxymecuribenzoic acid (pHMB). The biologically active components of C. longa rhizome were characterized by spectroscopic analysis as the curcuminoids curcumin (1), demethoxycurcumin (2), and bisdemethoxycurcumin (3). Curcumin was a potent inhibitor of sortase A, with an IC50 value of 13.8 +/- 0.7 microg/mL. Bisdemethoxycurcumin (IC50 = 31.9 +/- 1.2 microg/mL) and demethoxycurcumin (IC50 = 23.8 +/- 0.6 microg/mL) were more effective than pHMB (IC50 = 40.6 +/- 1.2 microg/mL). The three isolated compounds (1-3) showed no growth inhibitory activity against S. aureus strain Newman, with minimum inhibitory concentrations (MICs) greater than 200 microg/mL. Curcumin also exhibited potent inhibitory activity against S. aureus cell adhesion to fibronectin. The suppression of fibronectin-binding activity by curcumin highlights its potential for the treatment of S. aureus infections via inhibition of sortase activity. These results indicate that curcumin is a possible candidate in the development of a bacterial sortase A inhibitor.

Tomato cultivars respond differently to nitrogen (N) sources and to saline conditions, in terms of both yield and fruit quality. Interactions between salinity and ratios with tomato genotypes were studied. The effect of four ammonium levels (0, 1, 2, 4 mM of total 8 mM N) and two salinity levels (0 and 45 mM NaCl) on cv. “R-144”, and the effect of two salinity levels (0 and 45 mM NaCl) on four tomato hybrids (“R-144”, “R-175”, “FA612”, and “FA624”) were studied in two greenhouse experiments. The effects of two levels, (0 and 2 mM out of total N at 8 mM), and two salinity levels (0 and 20 mM NaCl) on large-fruit (“R-144”) and small-fruit (“FA612”) tomato hybrids were also studied in a net-house. The NaCl at 45 mM resulted in a smaller leaf area index (LAI), lower plant dry matter and lower fruit yield than controls. Addition of 1 mM to the nutrient solution contributed to improved growth. Genotypes bearing large fruits were more prone to suffer yield losses under saline conditions than those with ...

Lipid oxidation is a very complex and important event causing quality loss of foods, especially those containing highly unsaturated fats. There is growing interest in replacing synthetic antioxidants in food by natural counterparts. Olive leaf is an abundant by-product of the olive oil industry. The aim of this study was to investigate the antioxidant capacity of olive leaf powder (OLP) in minced Atlantic horse mackerel stored at 4 °C over 3 days. OLP was introduced in the minced at concentrations of 0 (control), 1.5, 3.5, and 4.5%. OLP characterization showed high antioxidant capacity and fiber content. The addition of OLP significantly prevented and delayed minced fish oxidation over storage. The antioxidant effectiveness of OLP was concentration-dependent, as observed in all the parameters analyzed. The results showed OLP as a potential natural antioxidant for fish products. Practical applications Olive leaves are an important agrifood by-product produced worldwide. This by-product is valorized for the first time, as far as the authors are aware, as natural antioxidant in fish. Olive leaves are rich in polyphenols (principally oleuropein) and α-tocopherol. Consumers may benefit from this research as there is an increasing demand for natural ingredients, along with concern about the environmental effects of food production. The results of the present study suggest that olive leaf powder can be successfully employed as natural ingredient to prevent oxidation in chilled horse mackerel mince. This allows transforming this by-product stream into a commercially valuable antioxidant.

The root essential oil of Ligusticum grayi Coult. & Rose (Apiaceae) was found to contain three volatile non-terpenoid hydrocarbons: the known C11 compound viridene, whose structure is hereby corrected to 1-[(2Z)-pent-2-en-1-yl]cyclohexa-1,3-diene; and the heretofore unreported C10 compounds 1-[(2Z)-but-2-en-1-yl]cyclohexa-1,3-diene (norviridene), and (Z)-but-2-en-1-ylbenzene (ar-norviridene). These compounds are structurally similar to the 3-alkylphthalides that are widespread in the Apiaceae and, like the latter, probably arise from polyketide precursors.

Mesquite (Prosopis spp.) are woody leguminous plants that belong to the family Leguminosae and grow in arid and semiarid regions of America, Africa and Asia. Prosopis spp. produce indehiscent fruit (pods) that can be milled to yield flour that is sold commercially and is used in pastries and baked goods. The major volatile constituent of mesquite flour was identified as 5,6-dihydro-6-propyl-2H-pyran-2-one on the basis of its Kovats index and mass spectrum. Using d-nonalactone as an internal standard its concentration was determined to be 59.75 ± 7.07 mg/kg (n = 3).

Antimalarial activity of anthothecol, a limonoid of Khaya anthotheca (Meliaceae) against Plasmodium falciparum was tested using a [(3)H]-hypoxanthine and 48h culture assay in vitro. Anthotechol showed potent antimalarial activity against malaria parasites with IC(50) values of 1.4 and 0.17microM using two different assays. Also, gedunin had antimalarial activity with IC(50) values of 3.1 and 0.14microM. However, the citrus limonoids, limonin and obacunone did not show any antimalarial activity. The antimalarial activities were compared with the three currently used antimalarial medicines quinine, chloroquinine and artemisinin.

Volatile constituents of California skullcap (Scutellaria californica A. Gray) flowers were isolated by solid-phase microextraction (SPME) and analyzed by GC and GC/MS. A total of 52 constituents were identified (constituting 90.8% of the total area), 12 of which were tentatively identified. β-Caryophyllene (56.6%), germacrene D (6.9%), methyl 2-methylbutyrate (4.9%), β-bourbonene (4.5%), α-humulene (2.8%), methyl butyrate (2.7%), and α-copaene (1.5%) were the major constituents of the flower volatiles. Due to their low odor thresholds (measured in water) and fruity aroma, methyl 2-methylbutyrate (4.9%; odor threshold = 0.1 ppb) and ethyl 2-methylbutyrate (0.7%; odor threshold = 0.007 ppb) were considered to be important contributors to the characteristic sweet, apple-like odor of these flowers.

Three anthocyanins were isolated from the acidified methanol extracts of UI 911 black beans (Phaseolus vulgaris L.) using solid phase extraction and preparative high-performance liquid chromatography . The anthocyanins were characterized using chromatographic and spectroscopic methods as delphinidin 3-glucoside (56%), petunidin 3-glucoside (26%), and malvidin 3-glucoside (18%). The monomeric anthocyanin content was 213 ± 2 mg/100 g of black beans (moisture content was 10.04 ± 0.02%). Keywords: Black beans; antioxidants; pigments; anthocyanins; electrospray ionization mass spectrometry

MS with GC-RI evidence was found for the presence of linden ether in cooked carrot (Daucus carota). Evaluation of the GC effluent from cooked carrot volatiles using aroma extract dilution analysis (AEDA) found linden ether with the highest flavor dilution (FD) factor. Others with 10-fold lower FD factors were β-ionone, eugenol, the previously unidentified β-damascenone, (E)-2-nonenal, octanal (+ myrcene), and heptanal. All other previously identified volatiles showed lower FD factors. Odor thresholds, concentrations, and odor activity values of previously identified compounds are reviewed. This indicated that at least 20 compounds occur in cooked carrots above their odor thresholds (in water). Compounds showing the highest odor activity values included β-damascenone, (E)-2-nonenal, (E,E)-2,4-decadienal, β-ionone, octanal, (E)-2-decenal, eugenol, and p-vinylguaiacol.

Root oil of Ligusticum grayi (Apiaceae) contains numerous irregular sesquiterpenoids. In addition to the known acyclic sesquilavandulol and a sesquilavandulyl aldehyde, two thapsanes, one epithapsane, and 14 sesquiterpenoids representing eight hitherto unknown carbon skeletons were found. These skeletons are: prethapsane, i.e. 1,1,2,3a,7,7-hexamethyloctahydro-1H-indene; isothapsane, i.e. 1,2,3a,6,7,7a-hexamethyloctahydro-1H-indene; ligustigrane, i.e. 1,1,2,7,7,7a-hexamethyloctahydro-1H-indene; isoligustigrane, i.e. 1,1,2,6,7,7a-hexamethyloctahydro-1H-indene; preisothapsane, i.e. 1,1,2,3a,6,7-hexamethyloctahydro-1H-indene; isoprethapsane, i.e. 1,1,2,4,7,7-hexamethyloctahydro-1H-indene; allothapsane, i.e. 1,1,2,3a,7,7a-hexamethyloctahydro-1H-indene; and oshalagrane, i.e. 1,1,2,4,6,6-hexamethylspiro[4.4]nonane. The bicyclic sesquiterpenoids are presumably biosynthesized by head-to-head coupling of geranyl diphosphate and dimethylallyl diphosphate, followed by a cyclization sequence leading to a hydroindane skeleton with six one-carbon substituents. Subsequent rearrangements--primarily methyl migrations--account for the remarkable variety of structures represented in L. grayi root oil.

The volatiles of Asian pear (Seuri cultivar) were studied by high-resolution gas chromatography and combined gas chromatography/mass spectrometry (GUMS) using vacuum simultaneous distillationextraction of blended fruit and dynamic headspace sampling of intact and enzymatically inhibited blended fruit. Esters were the dominant constituents in all of the samples. A total of 72 components were identified in the headspace of intact fruit, including 39 constituents reported for the first time in pear. Odor unit values calculated from concentration and odor threshold data indicate that the following compounds are important contributors to pear aroma: ethyl 2-methylbutanoate, ethyl hexanoate, ethyl butanoate, ethyl 2-methylpropanoate, hexyl acetate, ethyl heptanoate, hexanal, ethyl pentanoate, and ethyl propanoate. Asian pears (Pyrus serotina) are a completely distinct species from the more common European-type pears (Pyrus communis L.) such as Bartlett and La France and are not a cross between apples and pears. Though the volatile constituents of Bartlett pears have been extensively investigated (Maarse and Visscher, 1984), there has been, to our knowledge, only one publication on the flavor compounds of Asian pears (Shiota et al., 1981). These researchers studied four Asian pear cultivars [Nijisseiki (20th Century), Kosui, Hosui, and Kikusuil and found distinct compositional differences between the peel and pulp. The peel contained major amounts of nonanal, cy-farnesene, phenylacetaldehyde, and straight-chain hydrocarbons with 19-23 carbon atoms, while the pulp had ethyl butanoate, hexanol, hexyl acetate, butylbenzene, and

T h e volatiles of pineapple essence were isolated by liquid-liquid extraction, fractionated on neutral alumina, and analyzed by high-resolution gas chromatography and coupled gas chromatography/mass spectrometry (GC/MS). Twenty-six constituents (1 tentative) were identified for the Wrst t ime in pineapple including the following sulfur compounds: methyl 3-(methylthi0)-(E)-2-propenoate, methyl 3-(methy1thio)-(2)-2-propenoate, ethyl 3-(methy1thio)-(E)-2-propenoste, ethyl 3-(methy1thio)-(2)-2propenoate, methyl 4-(methylthio)butanoate, ethyl 4-(methy1thio)butanoate (tentative), and dimethyl trisulfide. Their odor contribution t o pineapple aroma is assessed.

Analytical Methods in Flavor Research Comprehensive Two-Dimensional Gas Chromatography: Application to Aroma and Essential Oil Analysis Analytical and Sensory Characterization of Chiral Flavor Compounds via Capillary Gas Chromatography on Cyclodextrins Modified by Acetal-containing Side Chains Improved Application of Semiconducting Metal Oxides as a Detector for High-Resolution Gas Chromatography Measurement of Flavor-Soy Protein Interactions in Low Moisture Solid Food Systems by Inverse Gas Chromatography Flavor Chemistry of Foods Volatile Components and Characteristic Odorants in Headspace Aroma Obtained by Vacuum Extraction of Philippine Pineapple (Ananas comosus [L.] Merr.) C13-Norisoprenoid Concentrations in Grapes as Affected by Sunlight and Shading Effects of Characteristic Volatiles of Boiled Celery on Chicken Broth Flavor Identification of Aroma Components during Processing of the Famous Formosa Oolong Tea "Oriental Beauty" Volatile Constituents of Mesquite (Prosopis) Pods Flavor Formation Painting and Memory in the Discovery of Aroma Chemicals: The Case of Sulfur Containing Odorants and Odorant Precursors in Axillary Sweat Odour Effect of Irradiation and Other Processing Treatments on the Flavor Quality of Apple Cider Maillard Volatile Generation from Reaction of Glucose with Dipeptides, Gly-Ser and Ser-Gly The role of (5E)-2,6-Dimethyl-5,7-octadiene-2,3-diol as Aroma Precursor in Badea (Passiflora quadrangularis L.) Fruit Genes and Enzymes Involved in Strawberry Flavor Formation Volatiles from the Thermal Interaction of E-2-pentenal with Methionine or Cysteine under Non-aqueous Conditions Flavor Contribution and Formation of Epoxydecenal Isomers in Black Tea Sensory Evaluation of Foods and Flavors Mixture Suppression of Perceived Intensities in an Odor Mixture Why Naturally Healthy Berries May Be Seen as Unpleasant and Non-appetitive? Picking Aroma Character Compounds in Citrus limon Oils by Using Odor Thresholds in Aroma Mixtures Flavor Release and Perception of Custard Desserts: Influence of Food Composition and Oral Parameters Biological Activity of Essential Oils and Flavors Evaluation of the Antioxidant Potential of Various Plant Essential Oils Some Biological Effects of Raspberry Ketone and Its Precursor

Three tasty (BR-139, FA-624, and FA-612) and two less tasty (R-144 and R-175) fresh greenhouse tomato cultivars, which significantly differ in their flavor profiles, were screened for potent odorants using aroma extract dilution analysis (AEDA). On the basis of AEDA results, 19 volatiles were selected for quantification in those 5 cultivars using gas chromatography-mass spectrometry (GC-MS). Compounds such as 1-penten-3-one, ( E, E)- and ( E, Z)-2,4-decadienal, and 4-hydroxy-2,5-dimethyl-3(2 H)-furanone (Furaneol) had higher odor units in the more preferred cultivars, whereas methional, phenylacetaldehyde, 2-phenylethanol, or 2-isobutylthiazole had higher odor units in the less preferred cultivars. Simulation of the odor of the selected tomato cultivars by preparation of aroma models and comparison with the corresponding real samples confirmed that all important fresh tomato odorants were identified, that their concentrations were determined correctly in all five cultivars, and that differences in concentration, especially of the compounds mentioned above, make it possible to distinguish between them and are responsible for the differential preference. To help elucidate formation pathways of key odorants, labeled precursors were added to tomatoes. Biogenesis of cis- and trans-4,5-epoxy-( E)-2-decenals from linoleic acid and methional from methionine was confirmed.

The study was begun to learn more about volatile-producing tomato glycosides. Hydrolysis of the glycoside fraction was carried out at pH 2.5, 3.0, 4.1 and 5.0 to give the volatile aglycons, which were isolated by steam distillation extraction. Volatile compounds were identified by GC-MS.

Le defaut Rio provoque un arriere gout prononce de medicament. Le but de l'etude est d'identifier les composes responsables de ce defaut. Les composes volatils extraits sont analyses par CPG, CPG couplee a la spectrometrie de masse ou a une detection olfactive

The antiplatelet and antiproliferative activities of extract of Tabebuia impetiginosa inner bark (taheebo) were investigated using washed rabbit platelets and cultured rat aortic vascular smooth muscle cells (VSMCs) in vitro. n-Hexane, chloroform and ethyl acetate fractions showed marked and selective inhibition of platelet aggregation induced by collagen and arachidonic acid (AA) in a dose-dependent manner. These fractions, especially the chloroform fraction, also significantly suppressed AA liberation induced by collagen in [(3)H]AA-labeled rabbit platelets. The fractions, especially the chloroform fraction, potently inhibited cell proliferation and DNA synthesis induced by platelet derived growth factor (PDGF)-BB, and inhibited the levels of phosphorylated extracellular signal regulated kinase (ERK1/2) mitogen activated protein kinase (MAPK) stimulated by PDGF-BB, in the same concentration range that inhibits VSMC proliferation and DNA synthesis.

The growth-inhibiting activity of anthraquinone-2-carboxylic acid and lapachol identified in the inner bark of taheebo, Tabebuia impetiginosa, toward 10 human intestinal bacteria was evaluated by using a paper disk diffusion bioassay and compared to those of seven lapachol congeners (1,4-naphthoquinone, naphthazarin, menadione, lawsone, plumbagin, juglone, and dichlone) as well as two commercially available antibiotics, chloramphenicol and tetracycline. Anthraquinone-2-carboxylic acid exhibited very strong growth inhibition of Clostridium paraputrificum at 1 microg/disk while 100 microg/disk of lapachol was needed for moderate growth inhibition of the same organism. These two isolates exhibited weak inhibition of Clostridium perfringens and Escherichia coli at 100 microg/disk while no adverse effects were observed on the growth of Bifidobacterium adolescentis, Bifidobacterium bifidum, Bifidobacterium infantis, Lactobacillus acidophilus, and Lactobacillus casei at 1000 microg/disk. Structure-activity relationships indicate that a methyl group in the C-2 position of 1,4-naphthoquinone derivatives might play an important role in antibacterial activity.

The identities and possible origins of three minor unusual volatile components of tomato are discussed. These are pentyl nitrate, the first identification of a volatile alkyl nitrate in a fresh vegetable or fruit; 5-ethyl-2(5H)-furanone, which, besides its presence in tomato, was found to be a major autoxidation product of pure (Z)-3-hexenal; and 5-ethylcyclopentene-1-carbaldehyde, a likely unusual linolenic acid oxidation product.

The effects of methanol extract from Hericium erinaceus cultivated with Artemisia iwayomogi (HEAI) on proliferation of vascular smooth muscle cells and CCl(4)-induced hepatic damage were evaluated. HEAI was shown to have a potent inhibitory effect on the proliferation of vascular smooth muscle cells (VSMCs). Interestingly, a methanol extract of Hericium erinaceus showed no inhibitory effect on the proliferation of VSMCs, while a methanol extract of Artemisia iwayomogi possessed strong inhibitory effects on the proliferation of VSMCs. Therefore, the inhibitory effects of HEAI may be caused by the changes of chemical components in the culture broth after the addition of Artemisia iwayomogi in the HEAI growth media. HEAI also had a strong protective effect on CCl(4)-induced hepatic damage in rats. The activity was evaluated using biochemical parameters such as glutamic oxalacetic transaminase (GOT), glutamic pyruvic transaminase (GPT) and alkaline phosphatase (ALP). HEAI treatment caused a significant reduction in the activity of GOT but not of GPT and ALP in comparison with CCl(4) treatment alone. Histopathological studies showed that liver samples treated with HEAI were significantly different when compared to non-treated animals after CCl(4) exposure.

The determination of the odor thresholds of Furaneol and norfuraneol in water and in buffered solutions showed that their thresholds varied depending on the pH of the solution, being lower the more acid the solution. Calculations of concentration/threshold ratios showed that Furaneol occurs at a concentration well above its threshold and is among the 10 compounds with the highest probability of contributing to both fresh and processed tomato aroma and flavor. Norfuraneol, however, occurs below its threshold concentration in fresh tomato and only slightly above in the paste and has only a low probability of contributing.

Significant tomato matrix effects on the volatility of certain fresh tomato odorants were found. The concentrations of odorants such as (E,E)-2,4-decadienal, beta-damascenone, and beta-ionone, in crushed fresh tomato fruit obtained by solid-phase microextraction (SPME), resulting from a tomato matrix calibration curve were 5.5-, 2-, and 12-fold higher, respectively, than those calculated by calibration based on buffer solutions. Static headspace analyses indicated that, in most cases, the tomato matrix significantly retains the odorants relative to the buffer solution. Thus, the concentration of odorants in the headspace of tomato is lower than expected compared to a simple matrix such as buffer. CaCl(2), although needed in crushed fruit tissue to block enzymatic activity, was found to interact specifically with 2-isobutylthiazole, reducing its content in the headspace by at least 6-fold. If a matrix effect is found, analysis of the odorant molecule contents in the headspace rather than in the food is recommended in order to better evaluate their access to the olfactory receptors.

The water-soluble volatile components of fresh tomatoes were isolated by liquid-liquid continuous ether extraction of filtered blended tomato and separated from non-volatiles by high flow dynamic headspace sampling, after careful evaporation of the ether. Capillary GCMS analysis identified the important aroma compound 2,5-dimethyl-4-hydroxy-3(2H)-furanone (furaneol) and the related compound 5-methyl-4-hydroxy-3(2H)-furanone occurring in the fresh tomato at concentrations of the order of 2 mg and 10 mg/kg of tomato respectively. From the odor threshold and concentration evidence it seems probable that Furaneol contributes to fresh and processed tomato aroma.

High-flow dynamic headspace sampling with excess anhydrous sodium sulfate was found to be an effective method of isolating Furaneol from fresh tomatoes. Quantitative analysis was carried out by gas chromatography using maltol as internal standard. Furaneol was found in the highest concentrations (660-1100 ppb) in the summer crop of home-grown tomatoes and in some of the greenhouse hydroponically grown tomatoes, which are ripened on the plant before being transported to the supermarkets. Furaneol was found in the lowest concentrations (38-180 ppb) in the common ethylene-ripened, field-grown, supermarket tomatoes.

Consumption of tomato products has been associated with decreased risk of some cancer types, and the tomato antioxidant, lycopene, is thought to play an important role in the observed health effects. In this study, four carotenoids, trans-lycopene, phytofluene, phytoene, and zeta-carotene, were quantified in tomato products. Samples of raw tomatoes, tomato juice after hot break scalder, and final paste were obtained from two different processing plants over two years. Comparison of carotenoid levels throughout processing indicated that lycopene losses during processing of tomatoes into final paste (25-30 degrees Brix) ranged from 9 to 28%. The initial Brix level of the raw tomatoes appeared to influence the amount of lycopene loss that occurred, possibly due to the differences in processing time required to achieve the final desired Brix level of the paste. In general, no consistent changes in the other carotenoids were observed as a function of processing. The antioxidant activity of fresh tomatoes, tomato paste, and three fractions obtained from these products (i.e., aqueous, methanol, and hexane fractions) was also determined. In both a free radical quenching assay and a singlet oxygen quenching assay, significant antioxidant activity was found in both the hexane fraction (containing lycopene) and the methanol fraction, which contained the phenolic antioxidants caffeic and chlorogenic acid. The results suggest that in addition to lycopene, polyphenols in tomatoes may also be important in conferring protective antioxidative effects.

PREFACE 1. Chemical and Sensory Characterization of Food Volatiles: An Overview PART 1: INSTRUMENTAL ANALYSIS OF FOOD FLAVORS 2. Odor-Active Compounds of Dry-Cured Meat: Italian-Type Salami and Parma Ham 3. Aroma-Active Benzofuran Derivatives: Analysis, Sensory Properties, and Pathways of Formation 4. Volatile Constituents of Asafoetida 5. Gas Chromatographic Analysis of Chiral Aroma Compounds in Wine Using Modified Cyclodextrin Stationary Phases and Solid Phase Microextraction 6. Sensing Systems for Flavor Analysis and Evaluation 7. Novel Aspects of Tomatillo Flavour PART 2: CORRELATION BETWEEN SENSORY PROPERTIES AND CHEMICAL STRUCTURES OF FLAVOR COMPONENTS 8. Descriptors for Structure-Property Correlation Studies of Odorants 9. Influence of the Chain Length on the Aroma Properties of Homologous Epoxy-Aldehydes, Ketones, and Alcohols 10. Flavor Chemistry of Peppermint Oil (Mentha piperita L.) 11. Chemical and Sensory Properties of Thiolactones PART 3: SYNTHETIC, THERMAL REACTION, AND ENZYMATIC APPROACHES TO FLAVOR COMPONENTS 12. Synthetic Approaches to Chiral Flavor Components 13. Specifity of Glycosidases from Tea Leaves toward Glycosidic Tea Aroma Precursors 14. Biosynthesis of *g-Nonalactone in Yeast 15. The Formation of Strecker Aldehydes 16. Analysis of Low Molecular Weight Aldehydes Formed during the Maillard Reaction 17. Chiral 1,3-Octanediol Synthetic Studies Using Enzymatic Methods as Key Steps 18. Formation Pathways of 3-Hydroxy-4,5-dimethyl-2[5H]-furanone (Sotolone) in Citrus Soft Drinks PART 4: ADDITIONAL PROPERTIES OF FLAVOR COMPONENTS AND FLAVORS 19. Antimicrobial Activities of Isothiocyanates 20. Processing Modulation of Soymilk Flavor Chemistry INDEXES Author Index Subject Index

Volatiles were obtained from commercially prepared and laboratory-prepared rice cakes using high-flow dynamic headspace isolation with Tenax trapping. Analysis was carried out by capillary GC/MS. More than 60 compounds were identified. Major volatiles included 1-hydroxy-2-propanone, furfuryl alcohol, 2,5-dimethylpyrazine, 2-methylpyrazine, pyrazine, hexanal, furfural, pentanol, 3-hydroxy-2-butanone (acetoin), and ethyl-3,6-dimethylpyrazine. Although not ideally applicable to a dry product, concentration/threshold ratios indicated that the compounds with a high probability of contributing to the aroma and flavor included 3-methylbutanal, dimethyl trisulfide, 2-ethyl-3,5-dimethylpyrazine, 4-vinylguaiacol, hexanal, (E,E)-2,4-decadienal, 2-methylbutanal, 2-acetyl-1-pyrroline, 1-octen-3-ol, and 1-octen-3-one. Keywords: Rice cakes; volatiles; flavor; aroma; identification; concentrations; concentration/threshold ratios

Vegetables are edible plant products which can be modified stems, roots, leaves, flowers, or even fruits. They are usually classified on the basis of the part of the plant that is used for food. Stem vegetables include asparagus and kohlrabi while beets, carrots, radishes and turnips are root vegetables. Among the leaf and leafstalk vegetables are brussel sprouts, cabbage, celery, endive, kale, lettuce, rhubarb and spinach. The head or flower vegetables include artichokes, broccoli, and cauliflower. Garlic, leeks, and onions are classified as bulb vegetables. Botanically, the term “fruit” applies to the structure, usually containing seeds, which develops from the flower ovary after pollination and fertilization (Vaughan and Geissler, 1997). Therefore, beans, cucumbers, eggplant, okra, peppers, squash, sweet corn and tomatoes would be classified as fruits according to this definition. However, the important distinction between fruits and vegetables has come to be made on a usage basis; those plant products that are usually consumed with the main course of a meal are considered to be vegetables while those used mainly as desserts are considered fruits.

Foods and food ingredients produced via recombinant DNA techniques - an overview, Karl-Heinz Engel et al. Part 1 Regulatory oversight: US food and drug administration policy for foods developed by biotechnology, J.H. Marayanski regulatory oversight and safety assessment of genetically-modified foods in the European Union, Karl-Heinz Engel et al administrative oversight to ensure safety of biotechnologically-produced foods in Japan, Ryoji Takahara the role of the public and federal advisory committees in providing advice to the government on agricultural science policy, Alvin L. Young and Daniel D. Jones safety assessment of flavour ingredients produced by genetically-modified organisms, J.B. Hallagan and R.L. Hall. Part 2 Plants: determination of the safety of genetically-engineered crops, Keith Redenbaugh et al exotic germ plasm for allergenicity in transgenic foods, Oscar L. Frick use of plant virus genes to produce disease-resistant crops, Lynn E. Murry molecular cloning of cereal cystatins and evaluation of their antiviral and antipest effects, S. Arai et al safety assessment of the bacillus thuringiensis insecticidal crystal protein CRYIA(B) expressed in transgenic tomatos, H.P.J.M. Noteborn et al safety assessment of potatos resistant to Colorado potato beetle, P.B. Lavrik et al. Part 3 Microorganisms: improvement of beer brewing by using genetically-modified yeast, J. Vogel et al genetic modification of brewer's yeast to produce acetolactate decarboxylase and the safety aspects of the beer brewed by the transformed yeast, R. Takahashi et al safety aspects of genetically-modified lactic acid bacteria, W.P. Hammes et al. Part 4 Enzymes: enzymes from genetically-modified microorganisms, Sven Pedersen et al. Part 5 Animals: progress in genetic modifications of farm animals, V.G. Pursel.

The chemical composition of the volatiles from the Gaura drummondii (night-blooming) flowers was determined by GC/MS, NMR and IR. The major compounds found were: syn- and anti-2-methyl-butanal oximes. Ten other compounds were also identified.

La distillation sous vide de peau et de pulpe permet d'obtenir 62 constituants identifies par chromatographie gazeuse et spectrometrie de masse. Dans l'espace de tete de fruits intacts, on separe et identifie 99 constituants

Isolement par distillation sous vide et extraction liquide-liquide, separation et identification par chromatographie gazeuse sur colonne capillaire et spectrometrie de masse de 48 composes volatils dont 27 nouvellement decrits comme constituants de l'arome de ce fruit