Synthetic colourants in capsule dietary supplements on the Korean market.

This study developed a rapid and easy analytical method for the simultaneous determination of nine synthetic colourants (SCs) in capsule dietary supplements. Sample pretreatment involved thermal treatment to dissolve gelatin, using the enzymes protease and amylase to prevent the gelation of gelatin and fat-soluble substances removal using petroleum ether. The method was linear (r2 ≥0.999), with LOD of 0.009-0.029 µg/mL and LOQ of 0.42-1.40 µg/g. Recovery ranged from 90.9 to 108.9%. The relative expanded measurement uncertainty ranged from 4.1 to 6.3%. Allura Red AC (R40) and Brilliant Blue FCF (B1) were commonly detected in 20 of the 28 samples. Up to six SCs such as Tartrazine (Y4), Sunset yellow (Y5), Amaranth (R2), Erythrosine B (R3), R40 and B1 were detected in a single sample, ranging from 30.5 to 40.2 µg/g. Total content of SCs in various capsule supplements ranged from 0.3 to 73.7 µg/g.

Effect of various roasting, extraction and drinking conditions on furan and 5-hydroxymethylfurfural levels in coffee.

Furan and 5-hydroxymethylfurfural (5-HMF) were quantified in 108 coffee models prepared considering the species/origin of the coffee beans, roasting temperature/time, mesh size used to sieve the ground coffee beans, type of extraction water and extraction method. The effect of drinking conditions, such as adding sugar or cream, on furan and 5-HMF levels, was also studied. The range of furan and 5-HMF in coffee samples were 5-362 ppb and 51-1143 ppm, respectively. Furan levels were increased by 198-560% with increasing roasting temperature/time and by 106-399% in cold-brew extracts compared with espresso extracts. Among the mesh sizes used, 500 µm with espresso extraction, and 710 µm with cold-brew extraction led to maximal furan levels. 5-HMF concentration was highest in Robusta coffee and espresso extracts, and decreased by 17-76% with increasing roasting temperature/time. In a drinking condition study, furan level was remained unchanged, even when sugar or cream were added.

Analysis of volatile compounds in rooibos tea (Aspalathus linearis) using different extraction methods and their relationship with human sensory perception.

This study aimed to comparatively analyze the volatile flavor of rooibos tea (Aspalathus linearis) obtained by two commonly used flavor extraction methods, simultaneous distillation-extraction (SDE) and steam distillation under reduced pressure (DRP). The tea obtained by the two extraction methods, were analyzed by gas chromatography-mass spectrometry to identify volatile aroma-related compounds. Descriptive sensory analysis of the extracted rooibos tea flavor was carried out by a trained panel (n = 7). Fifty volatile compounds were identified, including 26 and 25 aroma-active compounds by SDE (45.9 µg/g) and DRP (37.5 µg/g), respectively. SDE recovered larger quantities of alcohols, acids, and esters, whereas DRP was useful for analyzing thermally unstable volatile compounds, including various alcohols, aldehydes, and hydrocarbons. Descriptive sensory analysis revealed that ketones and phenolic compounds may be responsible for the sensory attributes woody and grassy green, whereas the aldehydes and acidic compounds may contribute to floral and fruity.

Effect of roasting temperature and time on volatile compounds, total polyphenols, total flavonoids, and lignan of omija (Schisandra chinensis Baillon) fruit extract.

In this study, roasting was applied to enhance the volatile compound content and antioxidant activity of hot-air dried omija (Schisandra chinensis Baillon) fruit. The major volatile compounds were furfural, 1,8-cineole and terpinen-4-ol. Total volatile compound concentration in omija roasted at 150 ℃ for 15 min was approximately 4 times higher than that in hot-air dried omija. Contents of monoterpenes and sesquiterpenes in roasted omija were significantly increased, compared to that of the hot-air dried omija (P < 0.05). The contents of schizandrin in extracts of hot-air dried omija and omija roasted at 150 ℃ for 10 min were determined to be 28.9 and 106.5 mg/100 g extract, respectively. The content of gomisin A from roasted omija was about 5 times higher than that of hot-air dried omija. Through this study, it is believed that the usability of omija will be expanded.

Analysis of α-dicarbonyl compounds in coffee (Coffea arabica) prepared under various roasting and brewing methods.

This study investigated the correlations of α-dicarbonyl compounds (α-DCs), including glyoxal (GO), methylglyoxal (MGO) and diacetyl (DA), formed in coffee prepared under various roasting and brewing methods. The levels of α-DCs in Brazilian coffee beans (Coffea arabica) ranged from 28.3 to 178 µg/mL. Concentration ranges of GO, MGO and DA were 1.31-6.57, 25.5-159 and 1.50-12.9 µg/mL, respectively. The level of α-DCs increased with high roasting temperature, long roasting time, small coffee bean particles, mineral water and espresso brewing. In correlation analysis, the roasting temperature-time showed strong negative correlations with α-DCs in espresso (-0.886) and cold-brew coffee (-0.957). In espresso coffee, there was a strong negative correlation between the α-DCs and coffee bean particle size (-0.918).

Furan Levels and Sensory Profiles of Commercial Coffee Products Under Various Handling Conditions.

In this study, the levels of furan in coffee with consideration towards common coffee consumption was investigated. The concentration of furan in brewed coffee was the highest among the coffee types studied, with an average of 110.73 ng/mL, followed by canned coffee (28.08 ng/mL) and instant coffee (8.55 ng/mL). In instant and brewed coffee, the furan levels decreased by up to an average of 20% and 22%, after 5 min of pouring in a cup without a lid. The degree of reduction was greater when coffee was served without a lid, regardless of coffee type (P < 0.05). In canned coffee, the level of furan decreased by an average of 14% after storage at 60 °C without a lid, and the degree of furan reduction in coffee was greater in coffee served warm (60 °C) than in coffee served cold (4 °C). A time-dependent intensities of sensory attributes in commercial coffees with various handling condition were different (P < 0.05), suggesting that coffee kept in a cup with lid closed, holds the aroma of coffee longer than coffee in a cup without a lid. PRACTICAL APPLICATION: Consumption of coffee has increased rapidly in Korea over the past few years. Consequently, the probability of exposure to chemical hazards presence in coffee products increases. Furan is a heterocyclic compound, formed mainly from Maillard reaction, therefore present in coffee products. This work demonstrated the strategy to reduce the levels of furan in coffee products at individual consumer level, by investigating the levels of furan served in common handling scenarios of coffee in Korea: canned coffee, instant coffee, and brewed coffee. Findings of this study can practically guide industry, government, and consumer agencies to reduce the risk exposure to furan during coffee consumptions.

Korean research project on the integrated exposure assessment of hazardous substances for food safety.

OBJECTIVES: This survey was designed to conduct the first nationwide dietary exposure assessment on hazardous substances including the intakes of functional food and herbal medicine. In this paper, we introduced the survey design and the results of the dietary exposure status and internal exposure levels of lead (Pb), cadmium (Cd), and mercury (Hg). METHODS: We selected 4867 subjects of all ages throughout Korea. We conducted a food survey, dietary survey, biomonitoring, and health survey. RESULTS: Pb and Cd were the highest (median value) in the seaweed (94.2 µg/kg for Pb; 594 µg/kg for Cd), and Hg was the highest in the fish (46.4 µg/kg). The dietary exposure level (median value) of Pb was 0.14 µg/kg body weight (bw)/d, 0.18 µg/kg bw/d for Cd, and 0.07 µg/kg bw/d for Hg. Those with a blood Pb level of less than 5.00 µg/dL (US Centers for Disease Control and Prevention, reference value for those 1 to 5 years of age) were 99.0% of all the subjects. Those with a blood Cd level with less than 0.30 µg/L (German Federal Environmental Agency, reference value for non-smoking children) were 24.5%. For those with a blood Hg level with less than 5.00 µg/L (human biomonitoring I, references value for children and adults, German Federal Environmental Agency) was 81.0 % of all the subjects. CONCLUSIONS: The main dietary exposure of heavy metals occurs through food consumed in a large quantity and high frequency. The blood Hg level and dietary exposure level of Hg were both higher than those in the European Union.

Quality evaluation of noble mixed oil blended with palm and canola oil.

Noble blended oils (canola: palm oil = 3:7, 4:6, 5:5, 6:4 and 7:3) were prepared and their frying qualities were evaluated. Frying qualities such as fatty acid composition, acid value, peroxide value, viscosity, smoke point, color, antioxidant activity, and sensory evaluation were measured to elucidate the optimum blend ratio of canola and palm oil. The ratio of unsaturated to saturated fatty acid of the blended oils was higher than that of palm oil after frying 50 times. The blended oil (3:7, Ca: Pa) had a relatively high oxidative stability and its peroxide values were 44.2-70.7 meq/kg after frying. The 3:7 (Ca: Pa) blended oil had excellent flavor, taste, and texture compared to those of the other frying oils as a result of a sensory evaluation of raw and fried potatoes. The results suggest that the 3:7 (Ca: Pa) blended oil is a good alternative oil for frying potatoes.

Lead and cadmium in functional health foods and Korean herbal medicines.

Lead (Pb) and cadmium (Cd) in functional health foods (FHF) and Korean herbal medicines (KHM) were analysed by the standard addition method with inductively coupled plasma-mass spectrometry. A total of 672 samples were collected from 2347 people (1015 adults, 557 students and 775 infants and children) who lived in Korea. Pb and Cd concentrations were analysed in the samples (FHF, n = 535; KHM, n = 50). Method validation was carried out using standard reference material (SRM), recovery rate and limits of detection and quantification. Recovery rates for Pb and Cd using three SRMs were 94.9%-101.6% and 96.7%-115.2%, respectively. Mean Pb values in FHF and KHM were 0.146 and 0.349 mg kg⁻¹, respectively. Mean Cd levels in FHF and KHM were 0.035 and 0.056 mg kg⁻¹, respectively. Mean values in Spirulina and yeast products were the highest in the FHF samples (0.940 mg kg⁻¹ for Pb in Spirulina products and 0.115 mg kg⁻¹ for Cd in yeast products).

Mercury and methylmercury in Korean herbal medicines and functional health foods.

Total mercury (Hg) and methyl mercury (MeHg) were analysed in functional health foods (FHFs) and in Korean herbal medicines (KHMs). A total of 560 samples (FHFs, n = 511; KHMs, n = 49) were collected. The levels of total Hg in 416 samples were lower than the limit of detection. MeHg analysis was conducted in 45 samples and the ranges of MeHg levels in samples were less than the LOD of 38.92 ng g(-1). Weekly intake per body weight (WIPBW) values of total Hg in FHFs and KHMS were 0.89 and 11.77 ng kg(-1) BW, respectively. The margins of exposure (MOEs) of total Hg for FHFs and KHMS were 598,753 and 36,503, respectively. The WIPBW values of MeHg for FHFs and KHMS were 0.22 and 0.01 ng kg(-1) BW, respectively. MOE values of MeHg for FHFs and KHMS were 412,276 and 517,363, respectively.

Monitoring and risk assessment of pesticide residues in yuza fruits (Citrus junos Sieb. ex Tanaka) and yuza tea samples produced in Korea.

The objective of this study was to establish an analytical method to measure pesticides used to cultivate yuza (Citrus junos Sieb. ex Tanaka) and to analyze pesticide residue levels of yuza and yuza tea samples. Risk assessments were also performed by calculating estimated daily intake (EDI) and acceptable daily intake (ADI). An excellent linear correlation was achieved with coefficient correlation values of 0.9750-0.9999. Percent recoveries were 80.4-109.9% for most pesticides with a <6.9% relative standard deviation (RSD). The limits of quantification for the method were 0.10-0.67 µg/ml. The RSD of intra-day and inter-day variability was <15.3%. Seven pesticides in yuza (n=80) and yuza tea (n=75) were analyzed with the optimized analytical method. Acequinocyl, spirodiclofen and carbendazim were detected in yuza samples in the concentration range of 0.07-0.15 µg/g, 0.11-1.89 µg/g, and 0.03-5.15 µg /g, respectively, whereas chlorpyrifos, prothiofos, phosalone, and deltamethrin were not detected in yuza or yuza tea. The concentrations of acequinocyl, spirodiclofen and carbendazim ranged from 0.18-1.05 µg/g, 0.13-0.29 µg/g, and 0.17-2.36 µg/g, respectively, in yuza tea samples. The percent ratios of EDI to ADI for acequinocyl, spirodiclofen, and carbendazim were 24.6%, 22.7%, and 58.5%, respectively.

Multiresidue pesticide analysis in Korean ginseng by gas chromatography-triple quadrupole tandem mass spectrometry.

In this study, a new analytical method was developed based on gas chromatography-triple quadrupole tandem mass spectrometry (GC-MS/MS) and used to determine 32 multiclass pesticides in ginseng products. The analytical method was validated, yielding recovery rates in the range of 55.2-108.3%, with precision values expressed as relative standard deviation (RSD) lower or equal to 12% at the spiking levels of 30, 100, and 1000 µg/kg. Correlation coefficients and LOQs (limit of quantification) were in the range 0.9801-0.9989 and 0.15-70 g/kg, respectively. With these validation data and this method, multiresidue pesticides of ginseng samples (fresh ginseng (n=118), red ginseng (n=24), dried ginseng (n=10)) were analysed. Among them, the most frequently detected pesticide was tolclofos-methyl. Tolclofos-methyl was detected in 86.4% of fresh ginseng (18.25-404.5 µg/kg), 91.7% of red ginseng (13.14-119.4 µg/kg), and 87.5% of dried ginseng (23.15-3673 µg/kg).

Environmentally friendly preparation of pectins from agricultural byproducts and their structural/rheological characterization.

Apple pomace which is the main waste of fruit juice industry was utilized to extract pectins in an environmentally friendly way, which was then compared with chemically-extracted pectins. The water-based extraction with combined physical and enzymatic treatments produced pectins with 693.2 mg g(-1) galacturonic acid and 4.6% yield, which were less than those of chemically-extracted pectins. Chemically-extracted pectins exhibited lower degree of esterification (58%) than the pectin samples obtained by physical/enzymatic treatments (69%), which were also confirmed by FT-IR analysis. When subjected to steady-shear rheological conditions, both pectin solutions were shown to have shear-thinning properties. However, decreased viscosity was observed in the pectins extracted by combined physical/enzymatic methods which could be mainly attributed to the presence of more methyl esters, thus limiting polymer chain interactions. Moreover, the pectins which were extracted by combined physical/enzymatic treatments, showed less elastic properties under high shear rate conditions, compared to the chemically-extracted pectins.

Inhibitory effects of Tabebuia impetiginosa inner bark extract on platelet aggregation and vascular smooth muscle cell proliferation through suppressions of arachidonic acid liberation and ERK1/2 MAPK activation.

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.

Alleviation of aflatoxin B1-induced oxidative stress in HepG2 cells by volatile extract from Allii Fistulosi Bulbus.

The volatile extract from Allii Fistulosi Bulbus (VEAF) was isolated by steam distillation under reduced pressure, followed by continuous liquid-liquid extraction, and its effects on aflatoxin B1 (AFB1)-induced oxidative stress were investigated in human hepatoma cells (HepG2). The main constituents of the VEAF, identified by gas chromatography/mass spectrometry, were 2-octyl-5-methyl-3(2H)-furanone, 2-hexyl-5-methyl-3(2H)-furanone, 2,5-dimethylthiophene, 3,5-diethyl-1,2,4-trithiolane and 3,4-dimethyl-2,5-dihydro-thiophene-2-one. VEAF significantly inhibited the formation of intracellular reactive oxygen species caused by AFB1 in a dose-dependent manner, concomitant with a significant decrease in the AFB1-induced cytotoxicity. VEAF pretreatment significantly reduced the levels of thiobarbituric acid reactive substances, an indicator of lipid peroxidation, whereas increased the level of reduced glutathione. The level of 8-hydroxy-2'-deoxyguanosine, a DNA oxidative stress marker, was also decreased by 49-59% with pretreatment of VEAF. With respect to the activity of AFB1 metabolizing enzymes, VEAF significantly increased the activity of glutathione S-transferase, and significantly decreased the cytochrome (CYP) P450 3A4 activity, but had a little effect on the CYP1As. These results suggest that VEAF may be selectively effective in alleviating the AFB1-induced oxidative stress, and lead to cytoprotection against AFB1 exposure.

Antioxidative activity of volatile extracts isolated from Angelica tenuissimae roots, peppermint leaves, pine needles, and sweet flag leaves.

Volatile extracts were isolated from dried medicinal plants [Angelica tenuissimae roots (AT, Angelica tenuissima Nakai), peppermint leaves (PL, Mentha arvensis L.), pine needles (PN, Pinus sylvestris L.), and sweet flag leaves (SF, Acorus gramineus Rhizoma)] using steam distillation under reduced pressure, followed by continuous liquid-liquid extraction (DRP-LLE). The extracts were then analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The major volatile constituents of AT, PL, PN, and SF were 3-butylidene-4,5-dihydrophthalide (32 mg/g), menthol (18 mg/g), thunbergol (2.1 mg/g), and cis-asarone (37 mg/g), respectively. The inhibitory activity (%) of the extracts against hexanal oxidation ranged from 33 to 98% at a level of 50 microg/mL. Among the volatile extracts, PL and PN increased cell viabilities by 10 and 24%, respectively, at a dose of 1 microg/mL, compared to that of H2O2-treated brain neuroblastoma cells, SK-N-SH. However, a 20% reduction in the malonaldehyde level, an index for lipid peroxidation, was observed at only 1 microg/mL concentration of PN.

Inhibitory effects of volatile antioxidants found in various beans on malonaldehyde formation in horse blood plasma.

The inhibitory effect of aroma extracts isolated from dried soybeans, mung beans, kidney beans, and azuki beans on malonaldehyde (MA) formation from horse blood plasma oxidized with Fenton's reagent was determined by gas chromatography (GC) coupled with nitrogen-phosphorus detector (NPD). Aroma chemicals such as maltol, eugenol, benzyl alcohol, 1-octen-3-ol, butyrolactone, and 1-methyl-2-pyrrolidone, found in the aroma extracts of beans, were also examined for their inhibitory effect on the same system. Among the four aroma extracts tested, the aroma extract of soybeans exhibited the strongest antioxidant activity. Extracts of soybeans, mung beans, azuki beans, and kidney beans inhibited MA formation by 58%, 47%, 40%, and 23%, respectively, at the level of 400 microg/mL, whereas, alpha-tocopherol and BHT inhibited MA formation by 52% and 70%, respectively, at the same level. Among the tested aroma chemicals, the antioxidant activity decreased in the following order: eugenol>maltol>1-octen-3-ol>benzyl alcohol>butyrolactone>1-methyl-2-pyrrolidone.

Antioxidative activities of fractions obtained from brewed coffee.

The antioxidative activity of column chromatographic fractions obtained from brewed coffee was investigated to find antioxidants and to assess the benefit of coffee drinking. The dichloromethane extract inhibited hexanal oxidation by 100 and 50% for 15 days and 30 days, respectively, at the level of 5 microg/mL. A GC/MS analysis of fractions, which exhibited oxidative activity, revealed the presence of antioxidative heterocyclic compounds including furans, pyrroles, and maltol. The residual aqueous solution exhibited slight antioxidative activity. The inhibitory activity (%) of the seven fractions from an aqueous solution toward malonaldehde formation from lipid oxidation ranged from 10 to 90 at a level of 300 microg/mL. The results indicate that brewed coffee contains many antioxidants and consumption of antioxidant-rich brewed coffee may inhibit diseases caused by oxidative damages.

Antioxidative activities of volatile extracts from green tea, oolong tea, and black tea.

Antioxidative activities of volatile extracts from six teas (one green tea, one oolong tea, one roasted green tea, and three black teas) were investigated using an aldehyde/carboxylic acid assay and a conjugated diene assay. The samples were tested at levels of 20, 50, 100, and 200 micrograms/mL of dichloromethane. The results obtained from the two assays were consistent. All extracts except roasted green tea exhibited dose-dependent inhibitory activity in the aldehyde/carboxylic acid assay. A volatile extract from green tea exhibited the most potent activity in both assays among the six extracts. It inhibited hexanal oxidation by almost 100% over 40 days at the level of 200 micrograms/mL. The extract from oolong tea inhibited hexanal oxidation by 50% in 15 days. In the case of the extract from roasted green tea, the lowest antioxidative activity was obtained at the level of 200 micrograms/mL, suggesting that the extract from roasted green tea contained some pro-oxidants. The extracts from the three black teas showed slight anti- or proactivities in both assays. The major volatile constituents of green tea and roasted green tea extracts, which exhibited significant antioxidative activities, were analyzed using gas chromatography-mass spectrometry. The major volatile chemicals with possible antioxidative activity identified were alkyl compounds with double bond(s), such as 3,7-dimethyl-1,6-octadien-3-ol (8.04 mg/kg), in the extract from green tea and heterocyclic compounds, such as furfural (7.67 mg/kg), in the extract from roasted green tea. Benzyl alcohol, which was proved to be an antioxidant, was identified both in a green tea extract (4.67 mg/kg) and in a roasted tea extract (1.35 mg/kg).

Antioxidant activity and characterization of volatile constituents of Taheebo (Tabebuia impetiginosa Martius ex DC).

Volatiles were isolated from the dried inner bark of Tabebuia impetiginosa using steam distillation under reduced pressure followed by continuous liquid-liquid extraction. The extract was analyzed by gas chromatography and gas chromatography-mass spectrometry. The major volatile constituents of T. impetiginosa were 4-methoxybenzaldehyde (52.84 microg/g), 4-methoxyphenol (38.91 microg/g), 5-allyl-1,2,3-trimethoxybenzene (elemicin; 34.15 microg/g), 1-methoxy-4-(1E)-1-propenylbenzene (trans-anethole; 33.75 microg/g), and 4-methoxybenzyl alcohol (30.29 microg/g). The antioxidant activity of the volatiles was evaluated using two different assays. The extract exhibited a potent inhibitory effect on the formation of conjugated diene hydroperoxides (from methyl linoleate) at a concentration of 1000 microg/mL. The extract also inhibited the oxidation of hexanal for 40 days at a level of 5 microg/mL. The antioxidative activity of T. impetiginosa volatiles was comparable with that of the well-known antioxidants, alpha-tocopherol, and butylated hydroxytoluene.