DISTRIBUTION OF PRIORITY POLYCYCLIC AROMATIC HYDROCARBONS IN THE SEDIMENT OF LAKE BALATON,HUNGARY

The determination of 13 PAH pollutants was carried out on sediment samples collected at 27 sites at the Lake Balaton, Hungary. The aim was to investigate the distribution patterns of PAHs and the correlation of source-sink relationship. Sediment samples were collected from the upper 10 cm and from 20 to 70 cm depth. The dry mass ratio of the fine grain-size fraction (<0.063 mm) and the coarse sand sediments (0.063–500 mm) were analyzed. Principal component analysis (PCA) was performed on the PAH compositional data for 110 samples to estimate the distribution of PAHs in different compartments. The average concentration of PAHs was found as 132 μg/kg dry weight (11–1734 μg/kg) for all sites and depth. Considering the harbors, at some sites, 930–950 μg/kg of total PAHs were obtained. The ratio of phenantrene/anthracene (PHE/AN) and fluoranthene/pyrene (FA/PY) indicated that most of the samples showed pyrogenic origin. It can be established that the upper 10 cm of the sediment is significantly more polluted than the deeper layers. The interim sediment quality guideline (ISQG) values and the probable effect level (PEL) were used to compare our findings with other data. No concentrations of PAHs were found higher than either ISQG and PEL values of samples collected inside of the lake, so the sediment has not been associated with adverse biological effects. However, the maximum concentrations of 7 out of 9 PAH compounds found in samples of harbors were higher than ISOG values but lower than PELs. Analysis of the harbor sediments revealed an elevated amount of contamination probably derived from the fuel of ships.     

Characterization of volatile compounds and triacylglycerol profiles of nut oils using SPME‐GC‐MS and MALDI‐TOF‐MS

Several nut oil varieties mainly used as culinary and overall healthy food ingredients were subject of the present study. Headspace solid‐phase microextraction combined with gas chromatography‐mass spectrometry was employed in order to determine the qualitative composition of volatile compounds. Furthermore, matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry was used in order to assess the profiles and relative composition of the prevalent triacylglycerols (TAG) within the oils. The headspace of the majority of oil samples was dominated by high contents of acetic acid (up to 42%) and hexanal (up to 32%). As nut oils are typically gained by cold‐pressing from previously roasted nuts, characteristic pyrazine derivatives as well as degradation products of long‐chain fatty acids were detected. TAG analysis of these oils revealed a quite homogeneous composition dominated by components of the C₅₂ and C₅₄ group composed mainly of oleic (18:1), linoleic (18:2), stearic (18:0) and palmitic (16:0) acid residues representing together between 65 and 95% of the investigated nut oils. The TAG profiles showed characteristic patterns which can be used as ‘fingerprints’ of the genuine oils. Nut oils exhibiting quite similar fatty acid composition (e.g. hazelnut, pistachio and beech oil) could be clearly discriminated based on TAG showing significant differences between the oils.     

Characteristics of pistachio kernel oils from Iranian cultivars

Ten pistachio samples from various Iranian cultivars were examined for some botanical features of their nuts and oil characteristics of their kernels. The wt of 100 nuts varied from 78.5 to 136.9 g. The nuts contained 44.1–58.9% kernel. Moisture of the kernels was low, 2.5–4.1%, and the kernels contained 55.2–60.5% oil. Unsaponifiable matter (0.72–0.96%), saponification value (189.0–193.6), refractive index (1.4635–1.4643), and iodine value (98.1–100.5) showed little differences in various samples. Fatty acids detectable by gas chromatographic analysis were: traces of myristic; 9.2–13.4%, palmitic; 0.5–1.1%, stearic; traces of arachidic; 0.5–1.0%; palmitoleic; 56.1–64.0%, oleic; 22.6–31.0%, linoleic; and 0.1–0.4%, linolenic. There were no significant differences due to origin and/or cultivar of the samples.     

Oxidative Stability of Pistachio (Pistacia vera L.) Paste and Spreads

In this study, pistachio (Pistacia vera L.) spread was prepared using pistachio paste, icing sugar, and red palm oil. Pistachio paste, pistachio spread without emulsifier, and pistachio spread with 1.5 % monoglycerides (Dimodan HP‐M, Danisco, Malaysia) were investigated to determine their oxidative stability by subjecting them to accelerated autoxidation conditions (60 °C). Pistachio paste and pistachio spread exhibit a great susceptibility to lipid oxidation due to their high‐fat content. However, it was found that the high oleic and palmitic contents of the oil increase its stability. In all the pistachio products examined, Totox values were higher than 10 (the maximum permitted level) after 25 days of storage. In none of the products was (E,E)‐2,4‐decadienal detected on day 0. After 25 days of storage, however, the peak area percentages rose to 0.13, 0.19, and 0.18 in pistachio paste, pistachio spread without emulsifier, and pistachio spread with emulsifier, respectively. Based on color investigations, the a value (i.e., less greenish) was increased in all the pistachio samples at the end of the storage period. Based on the results obtained from sensory evaluations as well as GC–MS, free fatty acid (FFA), and color measurements, it may be concluded that the shelf life of pistachio products is 20 days at 60 °C.     

Volatile lactones from streptomycetes arise via the antimycin biosynthetic pathway

The volatiles released by several streptomycetes were collected by using a closed-loop stripping apparatus (CLSA) and analysed by GC-MS. The obtained headspace extracts of various species contained blastmycinone, a known degradation product of the fungicidal antibiotic, antimycin A(3b), and several unknown derivatives. The suggested structures of these compounds, based on their mass spectra and GC retention indices, were confirmed by comparison to synthetic reference samples. Additional compounds found in the headspace extracts were butenolides formed from the blastmycinones by elimination of the carboxylic acid moiety. Analysis of a gene knockout mutant in the antimycin biosynthetic gene cluster demonstrated that all blastmycinones and butenolides are formed via the antimycin biosynthetic pathway. The structural variation of the blastmycinones identified here is much larger than within the known antimycins, thus suggesting that several antimycin derivatives remain to be discovered.     

Polycyclic Aromatic Hydrocarbons in Sediments of Marine Coastal Lagoons in Messina,Italy: Extraction and GC/MS Analysis,Distribution and Sources

The content of 21 polycyclic aromatic hydrocarbons (PAHs) were determined in 16 samples of sediments collected from Ganzirri and Faro marine coastal lagoons in Messina, Italy. Analysis was performed by gas chromatography/mass spectrometry (GC/MS) in selected ion monitoring (SIM) mode. The total concentration of polycyclic aromatic hydrocarbons (ΣPAHs) ranged from 74 to 5755 μg/kg of dry matrix. The resulting distributions and molecular ratios of specific compounds are discussed in terms of sampling location and origin of organic matter. The results obtained show that levels of contamination are not homogeneous throughout the stations, while the relative distributions of PAHs are homogeneous in most of the sampling stations. The organic matter content and PAH concentration were found to be correlated (r = 0.90). It is also shown that the pyrolytic origin is the main source of these compounds in Ganzirri and Faro Lakes sediments.     

Triphenyltin (IV) derivatives of N-acetyl amino acids,N-acetyl dipeptides and tripeptides: Preparation,NMR investigations and NMR spectroscopic resolution of the enantiomeric composition

Triphenyltin(IV) derivatives of N-acetyl amino acids ( 1a–g ) and N-acetyl di- ( 2a–f ) or tripeptides ( 3 ) mostly in the (L )- and the racemic (DL )-form have been prepared from bis(triphenyltin)oxide and the appropriate N-acetyl amino acid or N-acetyl peptide using various dehydrating agents. The compounds were characterized by NMR spectroscopy and elemental analysis. These compounds were studied at different concentrations and temperatures, revealing a strong self-association tendency. NMR investigations were undertaken in order to highlight preferred conformations of the peptide derivatives due to possible strong intramolecular associations between tin and nucleophilic donor atoms of the peptide moiety in weakly polar solvents. No preferred conformation was found which was in accordance with the underivatized peptides. The enantiomeric composition was determined by means of ¹H NMR spectroscopy using (−)-quinine hydrochloride and S-(−)-1-phenylethylamine as chiral solvating agents.     

Modification with Organometallic Compounds Improves Crossing of the Blood–Brain Barrier of [Leu5]‐Enkephalin Derivatives in an In Vitro Model System

Enkephalin peptides are thought to be suitable vectors for the passage of the blood–brain barrier (BBB). Modifications that do not alter the amino acid sequence are often used to improve the permeation through living membrane systems. As a new type of modification we introduce organometallic compounds, in particular ferrocene carboxylic acid. Derivatives of [Leu⁵]enkephalin were synthesised and labelled with organometallic compounds by using solid‐phase synthesis techniques. All new metal–peptide bioconjugates were comprehensively characterised by HPLC, NMR spectroscopy and mass spectrometry and found to be at least 95 % pure. For the first time, permeation coefficients in a BBB model for organometal–peptide derivatives were determined in this work. The uptake and localisation of fluorescein‐labelled enkephalins was monitored by fluorescence microscopy on three cancer cell lines. Octanol/H₂O partition coefficients of the compounds were measured by HPLC. The introduction of the organometallic moiety enhances the uptake into cells and the permeation coefficient of [Leu⁵]‐enkephalin. This could be due to an increase in lipophilicity caused by the organometallic label. The metal–peptide conjugates were found to be nontoxic up to mM concentrations. The low cytotoxicity encourages further experiments that could take advantage of the selectivity of enkephalin derivatives for opioid receptors.     

Determination of the country of origin of pistachio nuts by DSC and HPLC

The laboratories of the U.S. Customs Service frequently encounter the major analytical problem of determining the country of origin of imported commodities. This is particularly challenging with natural products. This paper will describe the process for one such commodity —pistachio nuts. Two approaches were taken, high performance liquid chromatography (HPLC) and Differential Scanning Calorimetry (DSC). It was found that the results of these two techniques were complimentary and confirmatory. The HPLC data was obtained on the petroleum ether soluble fraction of the pistachio nuts while the DSC runs evaluated both this fraction and the whole nut. The HPLC results were further investigated by collecting fractions from the eluting peaks, derivatizing them to form the methyl ester of the fatty acids, and profiling by gas chromatography to confirm the triglycerides originally present. The U.S. Customs Service is currently using DSC area ratios to screen imported pistachio nuts for country of origin.     

Chlorinated fatty acids in lipid class fractions from cardiac and skeletal muscle of Chinook salmon

Analysis of chlorinated fatty acids (CFA) in tissues can be difficult because of their low concentrations. This task becomes even more difficult when samples are from organisms living in remote locations with very little exposure to environmental contamination. Therefore, enrichment of CFA is necessary prior to analysis. In this study, CFA were enriched from fractionated lipid classes of cardiac and skeletal muscle of Chinook salmon (Oncorhynchus tshawytscha) to determine CFA distribution among lipid classes and tissue types and to demonstrate the sensitivity of this method to detect CFA at trace concentrations. The lipids extracted from cardiac and skeletal muscle of O. tshawytscha were separated into fractions containing TAG, FFA, and phospholipids. After transesterification, the FAME derivatives from each lipid class were analyzed by GC with a halogen-selective detector (XSD) to determine the concentrations of dichlorostearic acid and dichloropalmitic acid. Other chlorinated compounds detected byGC-XSD were analyzed by GC-MS. CFA were observed in all lipid classes in both cardiac and skeletal muscle tissues. However, the highest concentrations of CFA were found in the phospholipids of both tissue types, about 1–2 mg/g lipid. It was also shown that dichloropalmitic acid concentrated in cardiac phospholipids whereas dichlorostearic acid was found primarily in the phospholipids of skeletal tissue. CFA concentrations in TAG and FFA fractions were below 150 mg/g lipid. This study demonstrates a small-scale approach to the study of CFA at trace concentrations and their distribution among lipid classes.     

Floral Odors of Silene otites: Their Variability and Attractiveness to Mosquitoes

Inflorescence scent samples from nine populations of dioecious Silene otites, a plant pollinated by moths and mosquitoes, were collected by dynamic headspace extraction. Sixty-three scent samples were analyzed by gas chromatography–mass spectrometry. Out of 38 found, 35 compounds were identified, most of which were monoterpenoids, fatty acid derivatives, and benzenoids. Phenyl acetaldehyde was the most dominant compound in the majority of samples. The variability in scent composition was high, and population and sex differences were found. Nevertheless, wind tunnel experiments proved similar attraction of Culex pipiens pipiens biotype molestus mosquitoes to the inflorescence odor of S. otites of different populations, indicating that different blends are similarly attractive to mosquitoes. The electrophysiological responses of mosquitoes to the 12 most common and abundant odor compounds of S. otites differed. Linalool oxide (furanoid) and linalool evoked the strongest responses in male and female mosquitoes, and (Z)-3-hexenyl acetate was strongly active in females. Medium responses were evoked in males by (Z)-3-hexenyl acetate, in females by benzaldehyde and methyl salicylate, and in both sexes by lilac aldehyde, lilac alcohol, and linalool oxide (pyranoid).     

Rubber seed oil modified with maleic anhydride and fumaric acid and their alkyd resins as binders in water‐reducible coatings

Rubber seed oil (RSO) was modified with different amounts of maleic anhydride, and RSO alkyds (50% oil length) were modified to various extents by the incorporation of different amounts of maleic anhydride and fumaric acid. All the resins were evaluated as water‐reducible binders. Modification with maleic anhydride increased the acid and saponification values of RSO but reduced the iodine value. RSO modified with maleic anhydride exhibited lower amounts of volatile organic compounds (<20 g/L) than the corresponding RSO alkyds (34–87 g/L). The alkyd samples were superior to the modified RSO in chemical resistance. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3256–3259, 2003     

Macrocycle-functionalized polystyrene beads as specific absorbers

Crosslinked polystyrene beads were first functionalized with phenacyl ester linkers, and a series of four macrocycles with different ring sizes were synthesized from these linkers. The macrocycles were built from amide-linked monomers coupled by conventional peptide-synthesis methods. Annulation was achieved by copper(I)-catalyzed intramolecular azide–alkyne cycloaddition to give triazole linked macrocycles. The macrocycles were cleaved from the polymer beads with hydrazinolysis or saponification. The structures of macrocycles were confirmed by high-resolution nuclear magnetic resonance (NMR) and liquid chromatography–mass spectrometry (LC–MS) analysis. The ability of the polymers to selectively bind compounds from a mixture of aromatic derivatives in ethanol was tested. The prepared polystyrene supported macrocycles were found to selectively bind bromophenol blue and bromocresol green non-covalently with an association constant of 160–490 M⁻¹.     

Analysis of Phenolic Compounds and Antioxidant Activity in Wild Blackberry Fruits

Twenty three different wild blackberry fruit samples were assessed regarding their phenolic profiles and contents (by LC/MS quadrupole time-of-flight (QTOF) and antioxidant activity (ferric reducing ability of plasma (FRAP) and 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS)) by two different extraction methods. Thirty four phenolic compounds were detected (8 anthocyanins, 15 flavonols, 3 hydroxycinnamic acids, 6 ellagic acid derivatives and 2 flavones). In samples, where pressurized liquid extraction (PLE) was used for extraction, a greater increase in yields of phenolic compounds was observed, especially in ellagic acid derivatives (max. 59%), flavonols (max. 44%) and anthocyanins (max. 29%), than after extraction by the ultrasonic technique extraction (UAE) method. The content of phenolic compounds was significantly correlated with the antioxidant activity of the analyzed samples. Principal component analysis (PCA) revealed that the PLE method was more suitable for the quantitative extraction of flavonols, while the UAE method was for hydroxycinnamic acids.     

Gas chromatographic analysis of reactive carbonyl compounds formed from lipids upon UV-irradiation

Peroxidation of lipids produces carbonyl compounds; some of these, e.g., malonaldehyde and 4-hydroxynonenal, are genotoxic because of their reactivity with biological nucleophiles. Analysis of the reactive carbonyl compounds is often difficult. The methylhydrazine method developed for malonaldehyde analysis was applied to simultaneously measure the products formed from linoleic acid, linolenic acid, arachidonic acid, and squalene upon ultraviolet-irradiation (UV-irradiation). The photoreaction products, saturated monocarbonyl, α,β-unsaturated carbonyls, and β-dicarbonyls, were derivatized with methylhydrazine to give hydrazones, pyrazolines, and pyrazoles, respectively. The derivatives were analyzed by gas chromatography and gas chromatography-mass spectrometry. Lipid peroxidation products identified included formaldehyde, acetaldehyde, acrolein, malonaldehyde, n-hexanal, and 4-hydroxy-2-nonenal. Malonaldehyde levels formed upon 4 hr of irradiation were 0.06 μg/mg from squalene, 2.4 μg/mg from linolenic acid, and 5.7 μg/mg from arachidonic acid. Significant levels of acrolein (2.5 μg/mg) and 4-hydroxy-2-nonenal (0.17 μg/mg) were also produced from arachidonic acid upon 4 hr irradiation.     

Nonpolar-volatile lipids from soy protein isolates and hexane-defatted flakes

Lipid extracts from two samples of commercial soy protein isolates (SPI) and two samples of commercial hexane-defatted flakes were fractionated by silici acid-column chromatography. The material eluted with 100% chloroform was collected, further fractionated by silica solid-phase extractions, and analyzed by gas chromatography-mass spectroscopy by using mass spectra, retention times of authentic standards, and Kovats indices for identification. Thirty-eight compounds were identified and quantitated in the lipid fractions from soy protein isolates (SPI); 23 of these are reported for the first time as components of SPI. An additional 13 compounds are reported for the first time as components of hexane-defatted soybean flakes. The major classes of compounds reported for the first time associated with SPI include: butyl, methyl, and ethyl esters of fatty acids; phenols, diphenyls and phenyl esters; and abietic acid derivatives. Dehydroabietinal at 0.180 to 0.191 ppm of the protein isolates was the most abundant aldehyde in the SPI lipid extracts. The third most abundant aldehyde found in SPI after dehydroabietinal and hexanal was 2-butyl-2-octenal (0.065 to 0.086 ppm). Dehydroabietic acid methyl ester was present in SPI (0.309 to 0.459 ppm). Dehydroabietene (0.628 ppm) and abietatriene (0.396 ppm) were tentatively identified in one sample of hexane-defatted flakes.     

Determination of the adulteration of butter

The adulteration of butter is a serious problem due to economic advantages taken by replacing expensive milk fat with cheaper oil without informing the customers. The authentication of milk fat methods include analysis of bulk components, especially triacylglycerols, fatty acids, sterols and tocopherols. Fatty acid and sterol composition was analysed by using GC‐MS. TAG and tocopherol profiles were examined by HPLC with diode array (DAD) and fluorescence detectors (FLDs). In addition, identification of selected TAG of butter fat was conducted by LC‐atmospheric pressure chemical ionisation (APCI)/MS technique. The lipid composition of 16 different butters available on Polish market were investigated. The cholesterol content in butter fat ranged from 176.8 to 264.8 mg/100 g of fat and in two samples of milk fat β‐sitosterol was found. The total saturated fatty acid (SFA) content in milk fat was 67.1–73.5%, monounsaturated fatty acid 24.5–30.5% and polyunsaturated fatty acid was 1.2–2.0%. Abnormalities in fatty acid profiles, e.g. high concentration of linoleic fatty acid, were found in two butters. These abnormalities were also determined in TAG profiles. The examination of tocopherols in butter fat confirmed that two products were adulterated by the addition of plant oils because they contained δ‐tocopherol which is typical for plant origin foodstuffs. The methods described are useful for investigating milk fat adulterations, and the most efficient are analysis of sterols and tocopherols composition. Practical applications: The described methods are useful for investigating adulteration of milk fat. Traditional strategies rely on examination of fatty acids methyl esters and TAG; these methods have some disadvantages. Due to the variability of fatty acid composition of milk fat and because TAG analysis is complex and time consuming, FA analysis is not an efficient approach for butter authentication. The most efficient method for butter authentication is qualitative and quantitative analysis of sterols and tocopherols. This analysis will determine if components of plant origin were used for butter production.     

Optimization of nanofiber-caproate/laurate esters synthesis,their characterization,and usage as emulsifier in o/w emulsion

The aim of this study is to optimize the esterification of nanofibers with caproyl/lauroyl chlorides at different substitution degrees' (DS) and to investigate the usage of nanofiber derivatives in model emulsions. First, cellulosic material was obtained and milled into nanofibers using a micro-fluidizer. Then, these nanofibers were esterified with caproyl/lauroyl chlorides in a solvent of DMAc/LiCl with DMAP as an acid scavenger. The esterification of nanofibers with caproyl/lauroyl chlorides was optimized for fatty acid chloride mole and reaction time. Esterification reactions were carried out at 80°C with various molar ratios of acyl chlorides (3–15 moles) versus anhydroglucose unit of nanofibers and for various time durations (30–360 min). The hydrophobic derivatives with DS in the range of 0.34–2.77 were successfully obtained. Using the data obtained as a result of the optimization, nanofiber-fatty acid esters with different DS (0.50–2.75) were produced and characterized. Analyzes showed that the esterification process was successful and as the degree of esterification increased, the crystallinity index and thermal stability of the derivatives decreased. Then, the nanofiber-caproate/laurate esters with different DS were used as emulsifier (0.5 wt%) in an oil-in-water model emulsion containing 25 wt% oil and the emulsions were analyzed. The nanofiber caproate/laurate esters with a DS of 0.50–1.25 were suitable for o/w emulsions, while samples with a DS of 2.00 and above were not found suitable. Emulsions prepared by using nanofiber derivatives with 1.25 DS had higher G′ and G″ and viscosity values and lower droplet sizes than those of other group.     

脱氢枞基含氮衍生物的抑菌活性研究

采用平板计数法研究了脱氢枞酸（1）和脱氢枞基含氮衍生物（脱氢枞胺（2）、脱氢枞酸酰胺衍生物（3a~3m）、脱氢枞胺（取代）苯甲醛Schiff碱衍生物（4a~4i））对6种病原真菌的抑制活性。结果表明：脱氢枞胺的抑菌活性优于脱氢枞酸,脱氢枞胺（取代）苯甲醛Schiff碱衍生物的抑菌活性优于脱氢枞酸酰胺衍生物。其中含卤原子的脱氢枞胺（对氯）水杨醛Schiff碱（4d）、脱氢枞胺（间氟）苯甲醛Schiff碱（4f）、脱氢枞胺（对氟）苯甲醛Schiff碱（4g）、脱氢枞胺（对氯）苯甲醛Schiff碱（4h）具有较强的抑菌活性,4h在质量浓度为180 mg/L时对灰葡萄孢、腐皮镰孢和芸苔链格孢的抑制率达100%,抑制率接近阳性对照物放线菌酮。进一步测定了脱氢枞胺（取代）苯甲醛Schiff碱衍生物4d、4f、4g和4h在不同质量浓度下对6种病原真菌的抑菌活性。结果发现4种化合物在不同质量浓度下对灰葡萄孢和芸苔链格孢均具有较好的抑制活性。化合物4f在22.5 mg/L时对6种病原真菌的抑制率最高,均大于95%,而4g在22.5 mg/L时的抑制率却最低,并且4h在45 mg/L时的抑制率较高,上述结果表明苯环上卤原子的取代位置和类型均会影响其在不同质量浓度下的抑菌活性和最佳抑菌活性的质量浓度。     

Chemical evaluation of some paprika (Capsicum annuum L.) seed oils

The oil contents of seeds from paprika (Capsicum annuum L.) collected from different locations in Turkey and Italy varied in a relatively wide range from 8.5 g/100 g to 32.6 g/100 g. The fatty acid, tocopherol and sterol contents of the oils from different paprika seeds were investigated. The main fatty acids in paprika seed oils were linoleic acid (69.5–74.7 g/100 g), oleic acid (8.9–12.5 g/100 g) and palmitic acid (10.7–14.2 g/100 g). The oils contained an appreciable amount of γ‐tocopherol (306.6–602.6 mg/kg), followed by α‐tocopherol (7.3–148.7 mg/kg). The major sterols were β‐sitosterol (1571.4–4061.7 mg/kg), campesterol (490.8–1182.7 mg/kg), and Δ⁵‐avenasterol (374.5–899.6 mg/kg). The total concentration of sterols ranged from 3134.0 mg/kg to 7233.7 mg/kg. Remarkable amounts of cholesterol were found in the different samples (164.6–491.0 mg/kg). The present study showed that paprika seeds are a potential source of valuable oil that could be used for edible and industrial applications.