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1.
Four types of meju were made from 100%(w/w) defatted soybean (DFS), a mixture of 80%(w/w) defatted soybean, and 20%(w/w) glasswort (DFS-G), a mixture of 80%(w/w) defatted soybean and 20%(w/w) rice (DFS-R), and a mixture of 60%(w/w) defatted soybean, 20%(w/w) glasswort, and 20%(w/w) rice (DFS-GR). Four types of Korean traditional soy sauce were prepared from the 4 types of meju. Mineral and antioxidant contents in the soy sauce made of DFS-G and DFS-GR were significantly higher than others. Citric, malic, succinic, lactic, and pyroglutamic acid contents in soy sauce made of DFS-R and DFS-GR were 1.3–1.5 times higher than others. Total nitrogen and free amino acid contents in soy sauce were correlated with DFS concentration in the meju. The bacterial community in the non-fermented meju-making ingredients was replaced largely by Bacillus sp. in the fermented meju. The use of glasswort and rice in the meju-making process did not alter the bacterial community responsible for the fermentation of meju.  相似文献   

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The various extracts from chamdanggui (Angelica gigas Nakai) and sogdan (Phlomis umbrosa Turcz) were evaluated for estrogenic activity and characterized according to HPLC profile. Chamdanggui and sogdan were individually extracted with 4 solvents (hot water, 70% ethanol, n-butanol, and dichloromethane) of differing polarities. Estrogenic activity was determined by E-screen using an estrogen-dependent MCF-7 BUS cell. Although almost all extracts showed estrogenic effects in a concentrationdependent manner, the hot water extract from chamdanggui (250 μg/mL) had the higher effect (138%). Among 90 fractions using HPLC separation of the hot water extract from chamdanggui, fraction 21 and 28 produced the highest estrogenic effects of 178 and 163% at 10 μg/mL, respectively. The results imply that the hot water extract from chamdanggui could be useful as an alternative hormone replacement therapy.  相似文献   

4.
The fruit and thin-husked seeds of the pumpkin (Cucurbita pepo L.) and buckwheat grain (Fagopyrum esculentum Moench), both grown in Slovenia, were analysed for selenium (Se) content following foliar application of Se(VI) solution during the period of blooming. Samples were digested by a H2SO4-HNO3-H2O2-V2O5 mixture and Se determined, based on hydride generation atomic fluorescence spectrometry. The whole procedure from weighing to measuring was carried out in the same Teflon vessel. The detection limit of the method was 0.14 ng g–1 solution. Buckwheat seeds from untreated plants contained 47 ng g–1 of Se and 394 ng g–1 from plants after foliar fertilisation with Se. Pumpkin seeds from untreated plants contained 108 ng g–1 of Se, and 381 ng g–1 of Se from Se-treated plants, all per lyophilised sample. Se content in lyophilised pumpkin fruit was 15 ng g–1 in untreated plants and 20 ng g–1 in Se-treated pumpkin plants. It is thus feasible to enhance Se content in buckwheat and pumpkin seeds by foliar fertilisation, making them a rich source of dietary Se and useful as a raw material for enriched food products.  相似文献   

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The anthocyanins present in black carrot were extracted with pressurized water acidified with sulfuric, citric and lactic acids. Anthocyanin degradation became significant above 100 °C and there was no improvement when extraction pressure was increased to 100 bar. Therefore, the extraction from black carrot was carried out at temperatures 50, 75 and 100 °C under 50 bar pressure. The extraction efficiencies in terms of acylated and non-acylated anthocyanins were comparable for all three acids used to acidify water at 50 °C, while similar results were observed at 75 °C for both citric and lactic acids. Water acidified with lactic acid showed significantly higher extraction efficiency at 100 °C compared to water acidified with sulfuric and citric acids. Highest degree of polymerization together with increasing degree of browning was observed within extracts when sulfuric acid was used. On the other hand, when organic acids were used to acidify water, a higher extraction efficiency of anthocyanins, accompanied with a relatively low polymerization and browning was observed, with lactic acid giving the best results.  相似文献   

7.
Pigment composition of 15 black carrot cultivars (Daucus carota ssp. sativus var. atrorubens Alef.) was screened by HPLC-MS. Up to seven cyanidin glycosides, five of which were acylated with hydroxycinnamic and hydroxybenzoic acids, were identified and quantified in the roots by HPLC-DAD. Contents of individual compounds indicated great differences in the potential of anthocyanin accumulation both between different cultivars and carrots of the same cultivar. Total anthocyanin amounts ranged from 45.4 mg/kg dry matter to 17.4 g/kg dry matter. To the best of our knowledge, this is the first report on the quantification of individual anthocyanins in roots of different black carrot cultivars. The determination of color properties in the extracts under various pH conditions proved black carrot anthocyanins to be applicable as natural food colorants also for low-acid food commodities, whereas a considerable loss of color was noted under nearly neutral conditions. Additionally, relatively high saccharide contents were found in almost all cultivars which may be disadvantageous when coloring concentrates are produced from carrot roots.  相似文献   

8.
The aim of this paper was to study the biogenic amines (histamine, tyramine, putrescine, cadaverine, agmatine, spermine and spermidine) production of selected technological important lactic acid bacteria (strains of the genera Lactococcus, Lactobacillus and Streptococcus). Three methods (ion-exchange chromatography (IEC), PCR and cultivation method with pH indicator) were used. Within the 39 strains of lactic acid bacteria tested, the production of tyramine (formed by tyrosine decarboxylase) was detected in eight strains (3 strains of Lactococcus lactis subsp. lactis, three strains of Lactococcus lactis subsp. cremoris, 1 strain of Streptococcus thermophilus and 1 strain of Lactobacillus delbrueckii subsp. bulgaricus). The other tested biogenic amines were not detected. Cultivation in decarboxylation broth seems to be the least accurate method for the detection of biogenic amines due to enhanced risk of false-positive reactions. Therefore, in order to detect bacteria producing biogenic amines, the combination of PCR and chromatographic methods (e.g. IEC) can be recommended.  相似文献   

9.
Green tea has been credited with providing a wide variety of health benefits like higher total antioxidant, cancer prevention, and anti-irritant etc. Microencapsulation technology is used to prevent antioxidant loss during processing which involves entrapment of active material into carrier material. The experiments were designed using response surface methodology based on three level two factor (green tea extract, 10–25 % and drying inlet air temperature, 120, 130 and 140°C) central composite design. The feed emulsion was prepared with green tea extract as core material and 40 % maltodextrin concentration as wall material with the ratio of core to wall (1:2) and it was fed into the spray dryer at varied drying inlet air temperature to get encapsulated green tea extract powder. The quality characteristics were analysed such as moisture content, total antioxidant activity and total phenolic content and the process conditions were optimized using desirability function methodology. At optimum spray drying condition moisture content, total antioxidant activity and total phenolic content were found to be 3.1 % w.b., 72.91 % free radical scavenging activity by DPPH method, 57.81 mg/g of dry matter, expressed as gallic acid equivalent respectively with desirability value of 0.92.  相似文献   

10.
Wholemeal samples were obtained from five durum wheat cultivars at two different bug (Eurygaster spp.) damage levels (medium and high damage). The samples were incubated (60 and 120 min) and used in size exclusion high performance liquid chromatography (SE-HPLC) analyses. The results showed that the amount of larger polymeric protein (TP1) and smaller polymeric protein (TP2) obtained from total (sodium dodecyl sulfate soluble) proteins decreased significantly in the bug-damaged samples, while the amount of total larger monomeric proteins (TP3) increased. The polymeric/monomeric protein ratio of all cultivars decreased at 60 min of incubation with increasing damage level. For all cultivars, the ratio of unextractable polymeric protein (UPP%) significantly decreased at 60 min of incubation except cv. Diyarbakir. The results suggested that bug protease caused depolymerization and/or disaggregation of polymeric proteins to lower their average molecular size. The changes in protein structure as determined using SE-HPLC supported by the decreases in gluten content and gluten index values which decreased with suni-bug damage. Deteriorative effects of bug damage on durum wheat quality were found to be quite similar to those on bread wheats.  相似文献   

11.
Thermal inactivation of quality-related enzymes in both cauliflower crude enzyme extracts and fresh tissue samples was studied in temperature range 50–100 °C. For crude enzyme extracts, several parameters, reaction rate constants (k) and activation energy (E a) as well as decimal reduction time (D) and (z) values, were used to characterize the thermal stability. The rates of inactivation were found to follow first-order inactivation kinetics. Activation energies varied between 101.18 and 208.42 kJ mol−1 with z values of 10.59–24.09 °C. The examined kinetics indicated that lipoxygenase was the most heat resistant followed by peroxidase, polyphenol oxidase, pectin methyl esterase and ascorbic acid oxidase. Furthermore, the obtained results from the blanched fresh tissues indicated that inactivation of lipoxygenase secured disappearing of any other enzyme activities. Therefore, this study recommends using lipoxygenase as an indicator enzyme to optimize the thermal treatments of cauliflower products.  相似文献   

12.
Sprout-related foodborne disease outbreaks are increasingly becoming a concern for food safety. The primary sources of microbial contamination in ready-to-eat sprouts are contaminated seeds, which are improperly disinfected prior to sprouting. In recent years, the application of nonthermal plasmas for seed decontamination is increasingly being investigated as a substitute to regular pre-germination treatments. The present study was intended to evaluate the potentiality of corona discharge plasma jet (CDPJ) for decontaminating microorganisms on radish seeds and to determine the plasma exposure effects on the seed germination as well as physicochemical properties of sprouts grown from the CDPJ-treated seeds. Microbial contaminants, namely, aerobic bacteria, Bacillus cereus, Escherichia coli, Salmonella spp., and molds and yeast were detected in the seeds. All the microorganisms found in the seed samples were reduced in the range of 1.2–2.1 log CFU/g upon treatment using the CDPJ for 3 min. Pseudo-first-order kinetics provides the best fit to the microbial inactivation patterns. The plasma seed treatment for up to 2 min showed beneficial effects on seed germination rate and growth of seedlings. Compared to untreated controls, sprouts grown from the CDPJ-treated seeds exhibited no significant changes in the levels of moisture (mean range 85.45–87.51%), reducing sugars (0.547–0.550%), total phenolic content (6.14–6.29 μg GAL/g), and DPPH radical scavenging activity (78.03–78.60%). Sensory characteristics of radish sprouts grown from the plasma-treated (up to 2 min) seeds were not significantly different from controls. In conclusion, the CDPJ treatment of radish seeds for 2 min not only decreased the seed microbial counts but also led to the improvement of their germination rate and seedling growth, without negatively affecting the physicochemical and sensory properties of their corresponding sprouts.  相似文献   

13.
The peel of jinkyool (Citrus sunki Hort. ex Tanaka) has been widely used in traditional Asian medicine for treatment of a number of diseases, including indigestion and bronchial asthma. In the present study, we compared the flavonoids content and anti-inflammatory activities of ethanolic peel extracts from both immature and mature fruits. Comparing to the mature peel extract (MPE), the immature peel extract (IPE) contained more abundant flavonoids. IPE more effectively suppressed intracellular reactive oxygen species (ROS) generation (IPE, 67.6±1.2%; MPE, 78.9±2.4% at 300 μg/mL of control), nitric oxide (NO) production, and inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression, as well as interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) mRNA expression in lipopolysaccharide-stimulated RAW 264.7 cells. Additionally, IPE reduced c-Jun NH2-terminal kinase (JNK) and p38 mitogen-activated kinase (p38) activation, suggesting that IPE may exert an anti-inflammatory effect by suppressing pro-inflammatory cytokines that suppress activation of mitogen-activated protein kinases (MAPKs). Taken together, these results indicate that IPE has potential for use as an anti-inflammatory agent.  相似文献   

14.
A new rapid method based on real-time PCR was developed to detect four thermophilic Campylobacter species (Campylobacter jejuni, Campylobacter coli, Campylobacter lari, and Campylobacter upsaliensis) in food samples. The assay targeted the bipA gene for C. upsaliensis and C. lari, whereas the gene encoding the ATP-binding protein CJE0832 was used to detect C. coli and C. jejuni. These genes were chosen for this assay due to their low variability and mutation rate at a species level. The multiplex PCR showed 100% inclusivity for all 25 thermophilic Campylobacter strains tested and 100% exclusivity for 38 non-targeted strains belonging to closely related species. The newly developed real-time PCR could detect down to 102 genomes/reaction and displayed efficiency above 97% for all species except for C. upsaliensis (90.1%). The method proved to be a reliable tool for food analysis, showing 100% sensitivity, 96% efficiency, and 92.45% specificity when validated against the gold standard method UNE-EN ISO 10272:2006 using 200 diverse food samples (meat, fish, fruits and vegetables, and raw milk). In artificially spiked samples, the detection limit of the method was 10 cfu/g in salad, 5 cfu/g in turkey meat, and 1 cfu/g in the rest of meat samples tested. Consequently, the newly designed molecular tool represents a quick and safe alternative to obtain reliable results concerning the presence/absence of the main thermophilic Campylobacter in any food sample.  相似文献   

15.
The purpose of this study was to quantify the effectiveness of ultrasound treatment combined with controlled atmosphere storage (UCA) in preserving quality of cucumbers (Cucumis sativus L.) compared with the controlled atmosphere storage (CA) alone. The combination of ultrasound (especially at 200 W for 10 min) with CA (5% O2?+?2% CO2?+?93% N2) storage was most effective in preserving the fresh-like quality of cucumbers. The treatment reduced the loss in mass, firmness, soluble solids content and color, maintained cell wall integrity, and limited the redistribution of water in cucumbers. UCA significantly better preserved the flavor volatiles and retained the taste characteristics. This method also better preserved the intermolecular hydrogen and carbonyl bonding in aldehyde and ketone compounds of cucumbers which helped them to preserved longer. These results suggested that UCA can be a much effective preservation method than CA alone for fruits and vegetables.  相似文献   

16.
The heavy metal contents and chemical compositions among mackerel species were investigated. Atlantic and chub mackerel had higher mercury, but lower lead than blue mackerel. Chub mackerel had the highest crude fat (18.62%) and the lowest moisture (58.29%), whereas blue mackerel had the highest moisture (70.10%) and the lowest crude fat (2.89%). Atlantic and blue mackerel had total saturated fatty acids (SFA)>polyunsaturated fatty acids (PUFA)>monounsaturated fatty acids (MUFA), whereas chub mackerel had PUFA>SFA>MUFA. The main SFA of the 3 mackerels were 16:0 and the main PUFAs were 22:6n-3 and 20:5n-3. The total amino acid contents in Atlantic, blue, and chub mackerel were 190.63, 169.49, and 172.97 mg/g, respectively. The major amino acids of the 3 mackerels were glutamic acid, aspartic acid, lysine, and leucine.  相似文献   

17.
Esterases are enzymes that present good potential in industrial application, and soybean seed can represent an alternative source for this enzyme. The extraction and esterase activity of Brazilian soybean seeds (Glycine max L.) were evaluated. Esterase activity was found in both the germinated and non-germinated seeds at 2.90 and 1.70 U/mg, respectively, with a concentration in the powdered extract (freeze dried) of 100 mg/mL. The enzyme showed a preference for the hydrolysis of short chain fatty acids (120.02 U/mL) and optimum pH for activity was pH 8.0 with optimum temperatures of 40 and 80°C. The enzyme showed stability at 70°C showing 60% of residual activity and activity increased with the addition of the following salts: NaNO3, K2SO4, and Na2SO4 in the reaction medium.  相似文献   

18.
This study was carried out to find the possibility of fermenting yam (Dioscorea opposita Thunb.) with Lactobacillus acidophilus and the protective role on stomach lesion of rats. The solutions of raw and extracted yam used were 2 and 6%, and they were fermented by L. acidophilus at 37°C for 0, 12, 24, and 36 h. At intervals (0, 12, 24, and 36 h), viscosity, titratable acidity (TA), allantoin, and diosgenin were examined. In the results, it was observed the most desirable data at 12 h with 6% fermented raw yam (FRY) without any change in the content of allantoin and diosgenin. In the animal study by rats (Sprague-Dawley), the inhibition ratios on gastric lesion were 53.41% in FRY. Based on these data, it confirmed that raw yam powder fermented by L. acidophilus would be a functional food with the supplement of viable cells and nutraceutical component of allantoin and diosgenin.  相似文献   

19.
Isotherms of shiitake mushroom (Lentinus edodes) at 25 and 40°C were determined and drying kinetics of whole and sliced shiitake mushrooms were tested using a convective air drying method at different drying temperature of 40, 50, 60, and 70°C. The monolayer moisture contents of the mushroom were 7.23 and 5.44 g water/100 g of dry solids at 25 and 40°C, respectively. Both mushroom samples showed falling drying rate periods with increasing drying rates with increases in drying temperature, and the drying rate of the sliced mushrooms was faster than that of the whole mushrooms at the same drying conditions. The kinetic parameters for dehydration of the mushrooms were determined using the Newton model and the Classical diffusion model. Activation energy (E a ) values as determined using the Newton model were 22.58 and 20.48 kJ/mol for the whole and sliced mushrooms, respectively.  相似文献   

20.
‘Lemon Myrtle’ is becoming increasingly popular in Europe both for use in cuisine and phytotherapy. However, this common name covers two completely different species, Backhousia citriodora F. Muell. and Leptospermum citratum Challinor, Cheel & A.R.Penfold. These species differ with respect to secondary compounds and even can cause, if mixed up and applied in high dose, toxic effects. We describe how the two species can be discriminated microscopically making use of differences in the morphology of leaf pavement cells and the relative size of palisade parenchyma. Based on the large subunit of ribulose-1,5-bisphosphate carboxylase oxygenase (rbcL) as molecular marker, the phylogenetic position of the two species within the Myrtaceae could be clarified. This sequence information was used to develop a simple assay to discriminate the two species even in dried and highly fragmented mixtures as typically occurring in commercial samples. This assay utilises the occurrence of single-nucleotide exchanges between those species that produce different fragments when the rbcL amplificates are restricted with Sac II.  相似文献   

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