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1.
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   

2.
Isolation of the volatile fraction from the peel of Pontianak orange (Citrus nobilis var. Lour. microcarpa Hassk.) by a careful solvent extraction/vacuum distillation process followed by application of an aroma extract dilution analysis (AEDA) revealed 32 odour-active compounds in the flavour dilution (FD)-factor range of 4–2048, 26 of which could be identified. On the basis of high FD-factors, (R)/(S)-linalool, myrcene, (R)-limonene, and 1,8-cineole were characterised as the most potent odorants, followed by octanal, (E,E)-2,4-decadienal, nerol, (E)-2-dodecenal, geraniol, and (E,E)-2,4-nonadienal. In addition, one odorant resembling the characteristic sulphurous, resinous aroma of the Pontianak peel oil was detected with a quite high FD-factor of 128. By mass spectrometry followed by synthesis, 1-phenylethanethiol exhibiting an intense sulphurous, resinous smell at the very low odour threshold of 0.005 ng/L in air, was found to be responsible for the odour impression detected in the extract. 1-Phenylethanethiol occurring as a mixture of the (R)-(76%) and the (S)-enantiomer (24%) has previously not been reported as odorant in foods. Application of static headspace aroma dilution analysis (SHA) on Pontianak peel revealed the green, grassy smelling odour-active compounds hexanal and (Z)-3-hexenal as further important odorants in the headspace above the peels.  相似文献   

3.
In our previous work, Asterina pectinifera was fermented with Cordyceps militaris mycelia to improve its bioactivities and was reported to have strong antioxidant activities. The aim of the current study was to investigate its anti-inflammatory effect and mechanisms of action. In this study, we observed the inhibitory effect of the extract from fermented A. pectinifera with C. militaris mycelia (FACM) on nitric oxide (NO) production and its molecular mechanism in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. FACM could decrease LPS-induced NO production. Western blot analysis showed that FACM could down-regulate LPS-induced expression of inducible NO synthase without affecting cyclooxygenase-2. Moreover, FACM exhibited anti-inflammatory activity in LPS-induced RAW264.7 mouse macrophage cells through proinflammatory mediators including TNF-α and IL-6 via nuclear factor kappa B pathway. FACM inhibited LPS-induced phosphorylation of extracellular-signal-regulated kinase expression. Our results suggest that FACM may be a potential candidate for inflammation therapy by attenuating the generation of cytokines, production of NO, and generation of ROS in RAW264.7 cells.  相似文献   

4.
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   

5.
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   

6.
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   

7.
Nineteen odour-active compounds previously identified with high Flavour Dilution factors in an extract from the peel oil of Pontianak oranges (Citrus nobilis Lour. var. microcarpa Hassk.) were quantified using stable isotope dilution assays (SIDA). For this purpose, four new SIDA were developed, i.e. for the quantification of (E)-2-dodecenal, geraniol, nerol, and 1-phenylethanethiol. The results showed that (R)-limonene, myrcene, and (R)-α-pinene were the predominant compounds present in concentrations between 0.4 and 60 mg/g peel. An aroma recombinate containing the nineteen aroma compounds in the concentrations naturally occurring in the peel oil elicited the overall aroma of the peel oil itself, thus confirming the identification experiments. Furthermore, omission experiments showed that the unique odour quality of the peel is significantly influenced by the resinous, sulphurous-smelling 1-phenylethanethiol, although its concentration was only 38 ng/g peel.  相似文献   

8.
The pH of red ginseng extracts fermented with Saccharomyces cerevisiae and Saccharomyces carlsbergensis decreased rapidly during 3 days of fermentation, with no further significant change thereafter. After 20 days of fermentation, a relatively small difference remained in the acidity of extracts fermented with S. cerevisiae (0.54%) and S. carlsbergensis (0.58%). Reducing sugar in the S. cerevisiae and S. carlsbergensis extracts decreased from 258.6 to 45.4 and 43.2 mg/mL glucose equivalents, respectively; and ethanol contents increased from 1.5% at day 0 to 16.0 and 15.0%, respectively, at day 20. Ginsenosides Rb1, Rb2, Rc, Re, Rf, and Rg1 decreased during the fermentation with S. cerevisiae, but Rd and Rg3 increased by day 12. Ginsenosides Rb1, Rb2, Rc, Re, and Rg1 decreased gradually in the extract with S. carlsbergensis, but Rd and Rg3 were increased at day 6 and 9, respectively.  相似文献   

9.
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   

10.
‘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   

11.
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   

12.
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   

13.
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   

14.
15.
To acquire the effectiveness of oral treatments, aqueous extracts of Anodonta woodiana (HB) were incorporated into liposome and its antitumor activities evaluated in vivo. The HB-loaded liposomes (HBL) were prepared at a mean size of 14.85 μm by reverse-phase evaporation method. Referring to the maximum tolerated doses test, mice with orally administrated HBL, at a 3 g/kg body weight dosage, showed no obvious acute toxic sign. Furthermore, the tumoricidal activities of HBL against C26 murine colon carcinoma, Lewis lung tumor, human QGY hepatic carcinoma and MKN-45 gastric tumor were examined, respectively. In contrast to free HB, HBL possessed remarkable antitumor activity. Simultaneously, the effect of HBL was observed in a dose-dependent manner. For C26 murine colon carcinoma and Lewis lung tumor, the inhibitory ratios of HBL were 54.36 and 51.97% at a dose of 400 mg/kg, respectively. The suppression of tumor growth and the reduction in body weight were more pronounced in human QGY hepatic carcinoma and MKN-45 gastric tumors inoculated mice by treatment of HBL during 30 days. All these promising results implied that liposome-incorporated aqueous extracts of Anodonta woodiana had a more potential application as a natural antitumor and immunomodulator formulation.  相似文献   

16.
Fish protein hydrolysates (FPHs) were prepared from freshwater carps (Catla catla, Labeo rohita, and Cirrhinus mrigala) using flavorzyme at different degrees of hydrolysis (DHs) ranging from 5 to 20%. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical-scavenging activity of the FPHs prepared from the three species were in the range of 50–82%; the ferric reducing power of the FPHs prepared from catla was the highest. The linoleic acid peroxidation inhibition activity of the prepared FPHs varied from 71 to 91%. The emulsion activity index of the FPHs prepared from catla and rohu decreased significantly with an increase in the DH (p < 0.05). The emulsion stability index of the FPHs prepared from the three species was the highest at 20% DH. FPHs prepared from freshwater carps possess good antioxidant and surface-active properties and are therefore suitable to be used as natural antioxidants in health-food formulation and as water-soluble antioxidants in the food-processing industry.  相似文献   

17.
The prevalence, genetic diversity, and antibiotic susceptibility of Cronobacter species (Enterobacter sakazakii) isolated from sunshik products, its ingredients, and root vegetable farm’s soils were investigated to analyze main reservoirs and contaminated sources of Cronobacter spp. Cronobacter spp. was isolated from 9 of 15 sunshik products, 26 of 72 its ingredients, and 2 of 39 soils. The root vegetables such as sweet potato and carrot showed higher contamination rate (70%) than the other sunshik ingredients. All isolates showed 929 bp band amplified from 16S rRNA and resistant to ampicillin, amoxicillin/clavulanic acid, and cefazolin. All isolates showed diverse random-amplified polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE) band patterns. However, 3 cases of RAPD banding patterns between clinical strains and isolates from sunshik products and root vegetables (yam, carrot) were related with similarities level of 80%. These studies indicated that root vegetables can be an important contamination source of Cronobacter spp. in sunshik products. Thus, the preparation of root vegetables for manufacturing sunshik products used as a weaning diet was handled with more care than the other sunshik ingredients.  相似文献   

18.
The effect of the potentially probiotic bacteria strain of Lactobacillus acidophilus Bauer and probiotic bacteria Bifidobacterium animalis ssp. lactis BB12 on proteolytic changes of proteins in dry-cured loins during fermentation and cold storage was studied. Results of the conducted tests demonstrated that the use of probiotic bacteria for the production of dry-cured meats impacts the generation of products of protein proteolysis with high antioxidant activity. The highest antioxidant activity of peptides after fermentation and cold storage was observed in the loin with the strain B. animalis ssp. lactis BB12 and the loin with the mixture of strains L. acidophilus Bauer and B. animalis ssp. lactis BB12. Qualitative analysis of peptides demonstrated that peptides with weight below 3.5 kDa are characterized by the highest capacity of quenching the ABTS cation radical, including the peptides in loins with the strain B. animalis ssp. lactis BB12.  相似文献   

19.
We investigated the composition of muscle tissue from 30 untreated striped catfish (Pangasianodon hypophthalmus) and 40 untreated pikeperch (Sander lucioperca). The analyzed fillets had a mean moisture level of 77.5 % in striped catfish and 78.7 % in pikeperch. The mean level of protein content was 19 % in striped catfish and 20.5 % in pikeperch; the pH was 6.5 in striped catfish and 6.8 in pikeperch. Our data provide a first basis on a legal opinion concerning fishery products that are suspected to contain high amounts of added water. These data can also be used for the calculation of added water regarding the regulation of the European Union (EU) No 1169/2011, provision of food information to consumers.  相似文献   

20.
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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