Determination of macro, micro and trace elements in citrus fruits by inductively coupled plasma-optical emission spectrometry (ICP-OES), ICP-mass spectrometry and direct mercury analyzer.

BACKGROUND: Citrus fruits are widely consumed around the world. Several elements are known to have important physiological functions in living things, whereas others are reported to have toxic effects. This study was aimed to analyze the concentration of macro, micro and trace elements in citrus fruit varieties. Samples were acid digested using a microwave system and analyzed for macro elements by inductively coupled plasma-optical emission spectrometry (ICP-OES) and for micro and trace elements by inductively coupled plasma-mass spectrometry (ICP-MS). The application of analytical techniques was analyzed by determining method validation parameters including limits of detection and quantification, linearity, precision, spiking experiments and analyzing certified reference material (NIST CRM-1570a), Spinach leaves. RESULTS: The elemental levels of citrus fruits were found largely to be dependent upon the type of analyzed samples. Among nutritionally important elements, citrus fruits were good sources of potassium (95.13-270.4 mg kg-1 ), calcium (10.57-75.29 mg kg-1 ), zinc (466.5-1611 µg kg-1 ) and manganese (35.35-1902 µg kg-1 ). The concentrations of toxic elements (Pb, Cd, As, Al, Hg) were very low. CONCLUSION: In general, the concentrations of analyzed elements were within the critical levels specified by the Food and Agriculture Organization/World Health Organization and Food and Nutrition Board USA. Linear discriminant analysis successfully separated the samples into clear groups with 93.9% correct classification. © 2018 Society of Chemical Industry.

Determination of macro, micro, trace essential, and toxic elements in Garcinia cambogia fruit and its anti-obesity commercial products.

BACKGROUND: Garcinia (Clusiaceae) species are traditionally used as flavoring agents in curries and to cure several human health complications. This study investigated 31 macro, micro, and trace elements in microwave-assisted digested samples of Garcinia cambogia fruit and its anti-obesity commercial products by inductively coupled plasma-optical emission spectroscopy (ICP-OES) and inductively coupled plasma-mass spectrometric (ICP-MS) techniques. The methods were also validated using the coefficient of determination (R2 ), limits of detection and quantification (LOD, LOQ), precision (CV%), analysis of certified reference materials, spiking recovery experiments, and participation in an accredited laboratory proficiency test organized by Food Analysis Performance Assessment Scheme (FAPAS). RESULTS: Quality assurance confirmed that the methods were efficient and in accordance with criteria set by the Association of Official Analytical Chemists (AOAC). In the elemental analysis, the analyzed macro, micro, and trace essential elements were present in appreciable concentrations, which could meet the human nutritional requirements. Traces of toxic elements were within safe limits. CONCLUSION: From the results of the current study, the fruit and its commercial products could be considered potential sources of mineral elements without posing any threats to consumers. © 2018 Society of Chemical Industry.

Dietary intake assessment of macro, trace, and toxic elements via consumption of kimchi in South Korea.

BACKGROUND: Kimchi, a Korean food, is now produced and consumed in many other countries. In this study, the macro, trace, and toxic element content in varieties of kimchi from Korea and China was evaluated. A health-risk assessment, involving the calculation of estimated dietary intake values, was undertaken. To discriminate among samples with different origins, linear discriminant analysis (LDA) and principal component analysis (PCA) were applied. RESULTS: The analytical methods used for analyses were successfully validated. In the quantification of elements, no significant differences were detected in the concentrations of the elements that were analyzed. Based on the fresh weight of kimchi, among the macro elements, the concentrations of Na and K were relatively high, with values of 4181.9-9919.8 mg kg-1 and 1661.8-6623.5 mg kg-1 , respectively. Among the trace elements that were analyzed, zinc in Korean samples, and strontium in Chinese samples showed the highest concentrations, at 2.67 and 2.98 mg kg-1 , respectively. Concentration levels of the toxic trace elements were within permissible limits. The amount of daily intake and provisional daily intake of each element calculated based on kimchi intake confirmed its safety for consumption. Linear discriminant analysis and PCA successfully discriminated among the samples of Chinese and Korean origin. CONCLUSION: The provisional daily intake of the toxic elements was within provisional tolerable daily intake values. The normal intake of kimchi could not pose a threat upon consumption. © 2019 Society of Chemical Industry.

Determination of Volatile Flavour Profiles of Citrus spp. Fruits by SDE-GC-MS and Enantiomeric Composition of Chiral Compounds by MDGC-MS.

INTRODUCTION: Citrus fruits are known to have characteristic enantiomeric key compounds biosynthesised by highly stereoselective enzymatic mechanisms. In the past, evaluation of the enantiomeric ratios of chiral compounds in fruits has been applied as an effective indicator of adulteration by the addition of synthetic compounds or natural components of different botanical origin. OBJECTIVE: To analyse the volatile flavour compounds of Citrus junos Sieb. ex Tanaka (yuzu), Citrus limon BURM. f. (lemon) and Citrus aurantifolia Christm. Swingle (lime), and determine the enantiomeric ratios of their chiral compounds for discrimination and authentication of extracted oils. METHODOLOGY: Volatile flavour compounds of the fruits of the three Citrus species were extracted by simultaneous distillation extraction and analysed by gas chromatography-mass spectrometry. The enantiomeric composition (ee%) of chiral camphene, sabinene, limonene and ß-phellandrene was analysed by heart-cutting multidimensional gas chromatography-mass spectrometry. RESULTS: Sixty-seven (C. junos), 77 (C. limon) and 110 (C. aurantifolia) volatile compounds were identified with limonene, γ-terpinene and linalool as the major compounds. Stereochemical analysis (ee%) revealed 1S,4R-(-) camphene (94.74, 98.67, 98.82), R-(+)-limonene (90.53, 92.97, 99.85) and S-(+)-ß-phellandrene (98.69, 97.15, 92.13) in oil samples from all three species; R-(+)-sabinene (88.08) in C. junos; and S-(-)-sabinene (81.99, 79.74) in C. limon and C. aurantifolia, respectively. CONCLUSION: The enantiomeric composition and excess ratios of the chiral compounds could be used as reliable indicators of genuineness and quality assurance of the oils derived from the Citrus fruit species. Copyright © 2017 John Wiley & Sons, Ltd.

Volatile Organic Compounds of Anchote Tuber and Leaf Extracted Using Simultaneous Steam Distillation and Solvent Extraction.

Anchote (Coccinia abyssinica (Lam.) (Cogn)) is an endemic and potentially valuable crop of Ethiopia principally categorized under root and tuber crops, and its newly growing leaves along with the tendrils are also used as nutritious vegetable served after being cooked. Leaf and tuber powders were extracted for the first time to identify volatile organic compounds by simultaneous steam distillation and solvent extraction (SDE) and characterized using gas chromatography mass spectrometry (GC-MS). VOCs having an area percentage above 0.5% were used for identification analysis. From the results, thirty volatile flavor compounds from leaves and fifteen from tubers were identified with the total fraction yield of 770.57 mg/kg and 4536.91 mg/kg, respectively, and from the 30 compounds identified from leaf 16 were distinguished in each of the tested accessions. Ethyl acetate 90.47% (697.13 mg/kg) was detected in a higher amount exhibiting >1% peak area. The rest 6.03% (46.46 mg/kg) were minor quantities (<1%) of the total (770.57 mg/kg) volatile flavor fraction. Among the 15 identified compounds in the tuber, ethyl acetate was the only major compound that accounted together for 99.15% (4498.33 mg/kg) of the total volatile flavor fraction and 0.85% (38.58 mg/kg) being reported in minor quantities (<1%). The SDE extraction and GC-MS analysis of anchote leaves and tubers successfully identified various volatile flavor compounds, which indicates that anchote was found to be a potential source of volatile flavor compounds that can be used as a food flavoring agent and in folk medicines. Thus, this study confirms that anchote leaf and tuber can be used for more specific and valuable applications in food and medicine industries.

Extraction of volatile organic compounds from leaves of Ambrosia artemisiifolia L. and Artemisia annua L. by headspace-solid phase micro extraction and simultaneous distillation extraction and analysis by gas chromatography/mass spectrometry.

This study was designed to analyze the volatile organic compounds in the leaves of Ambrosia artemisiifolia L. and Artemisia annua L. from Korea. For extraction of volatile compounds, headspace-solid phase micro extraction (HS-SPME) and simultaneous distillation extraction (SDE) were applied and analyzed by gas chromatography/mass spectrometry (GC/MS). From the results, SDE extraction was found to give the highest concentration of volatile compounds with an average concentration of 1,237.79 mg/kg for A. annua L. leaves compared to 1,122.73 mg/kg by HS-SPME technique. A total of 116 volatile organic compounds were identified, including 76 similar volatile organic compounds detected by both the methods of extraction in leaves of subject species at varying concentrations. Among these 33 volatile organic compounds were reported for the first time from the subject plant species. Thus the present research findings extend the characterization of volatile organic compounds from leaves of A. annua L. and A. artemisiifolia L. species and reported some distinguishing compounds which may be used for their discrimination.

Elemental composition of pork meat from conventional and animal welfare farms by inductively coupled plasma-optical emission spectrometry (ICP-OES) and ICP-mass spectrometry (ICP-MS) and their authentication via multivariate chemometric analysis.

The demand of consumers from around the world for natural, nutritional and palatable pork meat is increasing with time. This study analyzed macro (Ca, K, Mg, Na, P), micro (Fe, Zn, Cr, Mn, Ni, Cu, Se, Sr, Cs), trace (Li, Be, V, Co, Ga, Ba, U), and toxic trace (As, Cd, TI, and Pb) elements of pork meat from conventional and animal welfare farms in South Korea. Among the elements analyzed by inductively coupled plasma-optical emission, and mass spectrometric (ICP-OES, ICP-MS) techniques, K, Fe, Mn, and Ni content were higher in animal welfare pork meat. The trace and toxic trace elements content were lower than the standard values. The principal component and linear discriminant analyses (PCA, LDA) explained the highest variance (99.82%, 99.00%) of the group based on toxic elements. These findings can thus be used to evaluate animal welfare and conventional farms pork meat quality in South Korea as well as worldwide.

Comparison of the quality characteristics of chicken breast meat from conventional and animal welfare farms under refrigerated storage.

In this study, we aimed to investigate the meat quality characteristics, bioactive compound content, and antioxidant activity during refrigerated storage of breast meat of Arbor Acres broilers (carcass weight: 1.1 kg, raised for 35 D) obtained from a conventional farm (BCF, n = 30) and an animal welfare farm (BAF, n = 30) in Korea. The BCF and BAF did not differ in their proximate composition, color, water-holding capacity, creatine, creatinine, and carnosine contents. However, the shear force value was significantly higher in BAF than in BCF (P < 0.05). The 2-thiobarbituric acid reactive substance (TBARS) levels in BCF on days 7 and 9 were significantly higher than those in BAF (P < 0.001). During storage, the total volatile basic nitrogen (VBN) content of BAF was significantly lower, except on day 1. The fatty acid composition of samples was not affected by the storage period, however, saturated fatty acid and unsaturated fatty acid contents did differ among the types of farm systems (P < 0.05). Although the creatine, creatinine, and carnosine contents in BAF and BCF did not differ significantly, the carnosine and creatinine contents decreased with the increase in storage period (P < 0.05). The anserine content of BAF was significantly higher than that of BCF throughout storage. Superoxide dismutase activity was not affected by the type of farm system but was affected by storage period. Overall, BAF showed lower pH, microorganism, TBARS, and VBN values, and higher anserine contents than BCF. These findings can serve as reference data for the evaluation of chicken meat quality of broilers raised in animal welfare farm and conventional farm.

Origin discrimination of defatted pork via trace elements profiling, stable isotope ratios analysis, and multivariate statistical techniques.

This study verified the origin of 346 defatted Korean and non-Korean pork samples via trace elements profiling, and C and N stable isotope ratios analysis. The analyzed elements were 6Li, 7Li, 10B, 11B, 51V, 50Cr, 52Cr, 53Cr, 55Mn, 58Ni, 60Ni, 59Co, 63Cu, 65Cu, 64Zn, 66Zn, 69Ga, 71Ga, 75As, 82Se, 84Sr, 86Sr, 87Sr, 88Sr, 85Rb, 94Mo, 95Mo, 97Mo, 107Ag, 109Ag, 110Cd, 111Cd, 113Cd, 112Cd, 114Cd, 116Cd, 133Cs, 206Pb, 207Pb, and 208Pb. Content (mg/kg) of 51V (0.012), 50Cr (0.882), 75As (0.017), 85Rb (57.7), and 87Sr (46.3) were high in Korean pork samples whereas 6Li, 7Li, 59Co, 55Mn, 58Ni, 84Sr, 86Sr, 88Sr, 111Cd, and 133Cs were found higher in non-Korean samples. The results of discriminant analysis showed that the trace elements content and stable isotope ratios were significant for the discrimination of geographical origins with a perfect discrimination rate of 100%.

Volatile organic compounds of Angelica gigas Nakai, Korean medicinal herb.

The study was performed to find out the profile of volatile flavor components from the aromatic medicinal plant, Angelica gigas Nakai. The volatile organic compounds of A. gigas Nakai were extracted by simultaneous steam distillation and extraction (SDE) method, and identified by gas chromatograph/mass spectrometric (GC/MS) analysis. A total of 116 compounds, including 40 hydrocarbons, 37 alcohols, 15 esters, 12 aldehydes, 7 ketones, and 5 miscellaneous were identified and quantified. Among them, 75 volatile organic compounds were detected which make up 90.52% of total volatile content. alpha-Pinene was detected as the prime volatile component which accounted for 30.89% of total volatile content and 2,4,6-trimethyl heptane, camphene, alpha-limonene, beta-eudesmol, vervenol, alpha-murrolene, and sphatulenol were detected as the major components of A. gigas Nakai.

Determination of volatile organic compounds, catechins, caffeine and theanine in Jukro tea at three growth stages by chromatographic and spectrometric methods.

Tea contains characteristic volatile organic compounds, polyphenols, caffeine and catechins, and is therefore among the most widely consumed beverages all over the world. In this study, fresh Jukro tea leaves collected from Damyang-gun (Jeollanam-do) at 40, 60 and 90day growth stages, were semi-fermented. The volatile organic compounds (VOCs) were extracted by simultaneous distillation-solvent extraction (SDE) and analyzed by gas chromatography/mass spectrometry (GC/MS). Catechins, caffeine and theanine were analyzed by high performance liquid chromatography (HPLC). A total of 159 VOCs were identified in the analyzed Jukro tea leaves. Comparatively, the increase in the concentrations of VOCs was high in 60day leaves. The content of catechins increased along the three growth stages, whereas caffeine, compared to 90day leaves, was higher for 40 and 60day leaves. Based on the results, the 60day leaves were found to be the most suitable and useful for making semi-fermented Jukro tea.

Geographical origin authentication of pork using multi-element and multivariate data analyses.

In the recent years, consumers have become increasingly concerned about the authenticity and labeling claims associated with meat and meat based products. In this study, investigating geographical origin authenticity of pork, 323 samples of pork belly were collected from Korea, USA, Germany, Austria, Netherlands and Belgium. These were analyzed for twenty-nine macro and trace elements using inductively coupled plasma-optical emission spectroscopy (ICP-OES), and ICP-mass spectrometry (MS). The applied analytical techniques were validated by quality assurance parameters in which the values of correlation coefficient, limits of detection and quantification, precision, and spiking recovery confirmed that the methods were well efficient and in accordance to the criteria set by the Association of Official Analytical Chemists (AOAC) for metals analysis. From the results of multivariate analyses, it was found that the trace elements are promising constituents which could be used to accurately determine the inter-continental provenance of pork.

IN VIVO CARBON TETRACHLORIDE-INDUCED HEPATOPROTECTIVE AND IN VITRO CYTOTOXIC ACTIVITIES OF GARCINIA HOMBRONIANA (SEASHORE MANGOSTEEN).

BACKGROUND: Garcinia hombroniana, known as "manggis hutan" (jungle mangosteen) in Malaysia, is distributed in tropical Asia, Borneo, Thailand, Andaman, Nicobar Islands, Vietnam and India. In Malaysia, its ripened crimson sour fruit rind is used as a seasoning agent in curries and culinary dishes. Its roots and leaves decoction is used against skin infections and after child birth. This study aimed to evaluate in vivo hepatoprotective and in vitro cytotoxic activities of 20% methanolic ethyl acetate (MEA) G. hombroniana bark extract. MATERIALS AND METHODS: In hepatoprotective activity, liver damage was induced by treating rats with 1.0 mL carbon tetrachloride (CCl4)/kg and MEA extract was administered at a dose of 50, 250 and 500 mg/kg 24 h before intoxication with CCl4. Cytotoxicity study was performed on MCF-7 (human breast cancer), DBTRG (human glioblastoma), PC-3 (human prostate cancer) and U2OS (human osteosarcoma) cell lines. 1H, 13C-NMR (nuclear magnetic resonance), and IR (infrared) spectral analyses were also conducted for MEA extract. RESULTS: In hepatoprotective activity evaluation, MEA extract at a higher dose level of 500 mg/kg showed significant (p<0.05) potency. In cytotoxicity study, MEA extract was more toxic towards MCF-7 and DBTRG cell lines causing 78.7% and 64.3% cell death, respectively. MEA extract in 1H, 13C-NMR, and IR spectra exhibited bands, signals and J (coupling constant) values representing aromatic/phenolic constituents. CONCLUSIONS: From the results, it could be concluded that MEA extract has potency to inhibit hepatotoxicity and MCF-7 and DBTRG cancer cell lines which might be due to the phenolic compounds depicted from NMR and IR spectra.

Elemental profiling and geographical differentiation of Ethiopian coffee samples through inductively coupled plasma-optical emission spectroscopy (ICP-OES), ICP-mass spectrometry (ICP-MS) and direct mercury analyzer (DMA).

This study was aimed to establish the elemental profiling and provenance of coffee samples collected from eleven major coffee producing regions of Ethiopia. A total of 129 samples were analyzed for forty-five elements using inductively coupled plasma (ICP)-optical emission spectroscopy (OES), ICP-mass spectrometry (MS) and direct mercury analyzer (DMA). Among the macro elements, K showed the highest levels whereas Fe was found to have the lowest concentration values. In all the samples, Ca, K, Mg, P and S contents were statistically significant (p<0.05). Micro elements showed the concentrations order of: Mn>Cu>Sr>Zn>Rb>Ni>B. Contents of the trace elements were lower than the permissible standard values. Inter-regions differentiation by cluster analysis (CA), linear discriminant analysis (LDA) and principal component analysis (PCA) showed that micro and trace elements are the best chemical descriptors of the analyzed coffee samples.

Identification and quantification of adulteration in Garcinia cambogia commercial products by chromatographic and spectrometric methods.

Species of genus Garcinia are rich sources of bioactive constituents with antimicrobial, anticancer, anti-inflammatory, hepatoprotective and anti-HIV activities. Commercial products of Garcinia cambogia are used as anti-obesity drugs with increasing market demand. Because of the high price of its products, it can be adulterated with similar lower-priced species. This study was designed to develop and validate an accurate and efficient method for the detection of any adulteration (G. indica) in G. cambogia products. For this purpose, high performance liquid chromatography (HPLC) was used to analyse the ethanolic fruit rind extracts of G. cambogia and G. indica, their formulations of 0.5, 1, 2, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90 and 95% G. indica with G. cambogia, and 11 G. cambogia commercial products. The analytical methods were validated by quality assurance parameters of linearity, sensitivity, precision and accuracy. Two marker peaks were detected in G. indica fruit extract, whereas G. cambogia did not show these peaks. The detected peaks were identified as anthocyanins; cyanidin-3-O-sambubioside and cyanidin-3-O-glucoside. In the study to determine the effect of pH and temperature on the stability of its anthocyanin content, HPLC analysis of G. indica extract showed the highest content at pH 1 and 50°C. Using two different mobile phases, the limits of detection (LOD) for cyanidin-3-O-sambubioside and cyanidin-3-O-glucoside were 0.036 and 0.059, and 0.022 and 0.033 mg kg-1, respectively. Furthermore, the inter-day precision (< 3.2%) confirmed that the applied analytical method fulfils the required criteria of Association of Official Analytical Chemists (AOAC). From this study, it was found that the HPLC method used for the detection of adulteration in G. cambogia products is rapid and accurate.

Changes in volatile flavor compounds in steam-dried Allium hookeri root.

This study was carried out to identify volatile flavor compounds in Allium hookeri root (AHR) and steam-dried AHR. The volatile compounds were extracted using a simultaneous steam distillation and extraction (SDE) method and identified by gas chromatography/mass spectrometry (GC/MS) analysis. Forty volatile compounds, present at a concentration of 76.10 mg/kg, were identified in AHR, with sulfur-containing compounds (96.8%) as the major volatile compounds. On the other hand, in two and four times steam-dried AHR, 34 volatile compounds present at 5.96 mg/kg and 28 compounds present at 4.23mg/kg were identified, respectively. This two and four times steam-dried AHR respectively contained sulfur-containing compounds (64.1 and 37.4%) and aldehydes (19.3 and 45.4%) as the dominant compounds. The sulfur-containing compounds decreased, whereas the aldehydes increased relative to levels in AHR with increased steam-drying time. This is the first report on volatile flavor compounds in AHR and steam-dried AHR.

Determination of toxic heavy metals and speciation of arsenic in seaweeds from South Korea.

This study aimed at determining the levels of toxic heavy metals including As, Pb, Cd, Al, Hg and As species, such as, As-III, As-V, MMA, DMA, AsB, and AsC in various edible species of seaweeds from South Korea. ICP-MS was used for determination of As, Pb and Cd, ICP-OES was used for Al, DMA was used for Hg, and LC-ICP-MS was used for As speciation. The analytical methods were validated by linearity, detection limits, precision, accuracy and recovery experiments, obtaining satisfactory results in all cases. From the results toxic heavy metals were found in the decreasing order of: Al>As>Pb-Cd>Hg. Generally concentrations of all analysed heavy metals and both organic and inorganic species of As were very low compared to PTWIs specified by JECFA and EC. Their contribution to the overall intake by the subject seafoods was found very low and thus would not pose any threat to consumers.

Analysis of radiolytic products of lipid in irradiated dried squids (Todarodes pacificus).

The lipid portion of dried squids (Todarodes pacificus) was extracted, and its hydrocarbons and 2-alkylcyclobutanones were separated using a florisil column. Both compounds were identified by gas chromatography and mass spectrometry and used to investigate the production of radiation-induced hydrocarbons and 2-alkylcyclobutanones. Concentrations of the hydrocarbons and 2-alkylcyclobutanones increased linearly with the radiation dosage. The major hydrocarbons in the irradiated dried squids were pentadecane and 1-tetradecene, which originated from palmitic acid. The amount of pentadecane was the highest among the radiation-induced hydrocarbons in the dried squids. The major 2-alkylcyclobutanone in the irradiated dried squids was 2-dodecylcyclobutanone, which was formed from the large amount of palmitic acid. 2-Tetradecylcyclobutanone, which may be produced from stearic acid in sample lipids, was also detected. Radiation-induced hydrocarbons and 2-alkylcyclobutanones were detected at > or = 0.5 kGy. These compounds were not detected in dried squids that were not irradiated. Radiation-induced hydrocarbons can be used as a detection marker for irradiated dried squids; however, the amount of 2-alkylcyclobutanones produced was not enough to be used as a marker. Radiolytic products of lipids, such as hydrocarbons or 2-alkylcyclobutanones. can be used to monitor food safety for consumers, ensuring proper irradiation labeling in foods and quarantine treatment in international trade.

Analysis of radiation-induced hydrocarbons and 2-alkylcyclobutanones from dried shrimps (Penaeus aztecus).

We investigated the usefulness of hydrocarbons and 2-alkylcyclobutanones as markers for irradiated, dried shrimps. A method was developed to detect the irradiation of dried shrimps (Penaeus aztecus) by identifying radiation-induced hydrocarbons and 2-alkylcyclobutanones extracted from dried shrimps, which were separated by Florisil column chromatography and identified by a method using gas chromatography/mass spectrometry. Radiation-induced hydrocarbons and 2-alkylcyclobutanones are formed from the fatty acids of the irradiated fats. The quantity of the hydrocarbons and 2-alkylcyclobutanones formed from some fatty acids is related to the composition of fatty acids in a sample. The concentrations of hydrocarbons and 2-alkylcyclobutanones increased with radiation dose. The major hydrocarbons in the irradiated, dried shrimps were 1-tetradecene and pentadecane from palmitic acid; small amounts of heptadecane and 1-hexadecene from stearic acid; and 8-heptadecene and 1,7-hexadecadiene from oleic acid. 2-(5'-Tetradecenyl)cyclobutanone, one of the 2-alkylcyclobutanones, was present at the highest concentration. The radiation-induced hydrocarbons and 2-alkylcyclobutanones were detected at radiation doses of 0.5 kGy and greater. These compounds were not detected in nonirradiated, dried shrimps.

Determination of toxic heavy metals in Echinodermata and Chordata species from South Korea.

This study aimed at analysing concentrations of heavy metals including arsenic, lead, cadmium, aluminium and mercury in commonly consumed seafood species belonging to Echinodermata (Anthocidaris crassispina and Stichopus japonicus) and Chordata (Halocynthia roretzi and Styela plicata). The samples were digested by a microwave system and analysed for As, Cd and Pb by inductively coupled plasma mass spectrometer, for Al by inductively coupled plasma-optical emission spectrometer and Hg by Direct Mercury Analyser. The analytical method was validated by determining sensitivity, linearity, precision, spiking recoveries and analysis of the Standard Reference Material (SRM) NIST 1566-b, an Oyster Tissue. Results showed considerably higher accumulation of Al and As in analysed samples, compared to Pb and Cd, while Hg had the lowest contamination. On comparison, the obtained results with the recommended standards by the Food and Agriculture Organization, European Commission and Ministry of Food and Drug Safety of Korea, it was concluded that the analysed seafoods were safe and thus would not pose a threat to consumers.