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1.
A potent anticoagulant oligopeptide was isolated from the edible parts of blue mussel (Mytilus edulis). M. edulis anticoagulant peptide (MEAP) with an approximately 2.5 kDa molecular mass was similar to the amino acid sequence of the EF-hand domain of calmodulin from scallop adductor muscle. MEAP could potently prolong both the thrombin time and the activated partial thromboplastin time, and specifically interact with blood coagulation factors: FIX, FX, and FII. MEAP could inhibit proteolytic activation of FX by the intrinsic FXase and formation of FIIa by a prothrombinase complex in dose-dependant reactions. This study elucidated that MEAP prolonged blood clotting by inhibiting activation of FX in the intrinsic tenase complex (FIXa/VIIIa/PLs) and conversion of FII to FIIa in the prothrombinase complex (FXa/FVa/PLs).  相似文献   

2.
Shu-Yao Tsai 《LWT》2007,40(8):1392-1402
Three mushrooms are currently available in Taiwan, including Agaricus blazei, Agrocybe cylindracea, and Boletus edulis. Their ethanolic and hot water extracts were prepared and antioxidant properties studied. Ethanolic extracts from three mushrooms were more effective than hot water extracts in antioxidant activity using the conjugated diene method and scavenging ability on 1,1-diphenyl-2-picrylhydrazyl radicals whereas hot water extracts were more effective in reducing power, scavenging ability on hydroxyl radials and chelating ability on ferrous ions as evidenced by their lower EC50 values. Overall, for both extracts, B. edulis was more effective among antioxidant properties assayed. Naturally occurring antioxidant components including total tocopherols (3.18-6.18 mg/g) and total phenols (5.67-5.81 mg/g) were found in the extracts and their contents were associated (r=0.636-0.907) with EC50 value of antioxidant properties. Based on the results obtained, both extracts from these three mushrooms were effective in antioxidant properties.  相似文献   

3.
Samples of fruit from the jussara palm plant (Euterpe edulis), collected in different regions of the state of Santa Catarina, Brazil, were analyzed for chemical composition, phenolic acids, anthocyanins, flavonoids and fatty acids profile. Results indicated that the jussara fruit has a high lipid content (18.45-44.08%), oleic acid (44.17-55.61%) and linoleic acid (18.19-25.36%) are the fatty acids found in the highest proportion, and other components were proteins (5.13-8.21%), ash (1.55-3.32%) and moisture (34.95-42.47%). Significant differences were found in the total phenolic, total monomeric anthocyanins and other flavonoids for the samples from the five cultivation regions. The fruit from region E harvested in summer, with high temperatures and medium altitudes, had the highest contents of total phenolics (2610.86 ± 3.89 mg 100 g−1 GAE) and monomeric anthocyanins (1080.54 ± 2.33 mg 100 g− 1 cy-3-glu). The phenolic compound included ferulic, gallic, hydroxybenzoic and p-coumaric acids, as well as catechin, epicatechin and quercetin. The results show promising perspectives for the exploitation of this tropical fruit with a chemical composition comprising considerable phenolic acids and flavonoids compounds and showing activity antioxidant.  相似文献   

4.
The shelf life of red mullet and goldband goatfish during ice storage were studied in terms of sensory, microbiological and chemical changes. The sensory acceptability limit was 8 days for goldband goatfish (Upeneus moluccensis) and 11 days for red mullet (Mullus barbatus) stored in ice. The TVC level was correlated with sensory assessment. The TVC exceeded 7 log cfu g−1 after 8 days for goldband goatfish, and 11 days for red mullet. At the end of storage period, pH, TVB-N, TBA, FFA and PV for red mullet were 7.84, 47.19 mg/100 g, 0.69 mg MA kg−1, 1.17% oleic acid and 1.58 meq O2/kg and for goldband goatfish they were 7.53, 43.97 mg/100 g, 0.74 mg MA kg−1, 1.62% oleic acid and 1.68 meq O2/kg, respectively. In red mullet, agmatine, serotonin, histamine and dopamine became the dominant amines, reaching 7.30, 5.97, 2.52 and 2.31 mg/100 g, respectively. Also the dominant amines for goldband goatfish were 4.37, 3.88, 3.38 and 2.00 mg/100 g for histamine, agmatine, dopamine and putrescine, respectively.  相似文献   

5.
Total phenolics, ascorbic acid, and antioxidant capacity of noni (Morinda citrifolia L.) juice and powder were determined during storage at 24 °C. After 2 weeks of storage, illuminated noni juice lost 32% of total phenolics, 89% of ascorbic acid, and 46–65% of antioxidant capacity—about 8%, 22%, and 9–15% more than unilluminated juice. Both illuminated and unilluminated juice lost 97% of ascorbic acid by 4 weeks. The difference in antioxidant characteristics between illuminated and unilluminated juice became insignificant at 12 weeks. After 12 weeks, illuminated noni powder lost 21% of total phenolics, 17% of ascorbic acid, and 23–36% of antioxidant capacity—about 13%, 4%, and 7–19% more than the unilluminated powder. Noni powder in brown bottles retained antioxidant characteristics significantly greater than that in clear bottles. Protection from light effectively reduced degradation of antioxidant characteristics of noni juice for only 2 weeks but those of noni powder for at least 3 months.  相似文献   

6.
Bioassay-directed isolation and purification of the ethyl acetate and methanol extracts of Amelanchier canadensis resulted in 1,3-dilinoleoyl 2-olein (1), 1,3-dioleoyl 2-linolein (2), 5-hydroxymethyl-2-furfural (3), 5-(sorbitoloxymethyl)-furan-2-carboxaldehyde (4), 5-(mannitoloxymethyl)-furan-2-carboxaldehyde (5), and 5-(α-d-glucopyranosyloxymethyl) furan-2-carboxaldehyde (6). Four compounds, oleanolic acid (7), ursolic acid (8), kaempferol-3-O-α-l-rhamnopyranosyl (1 ← 2) rhamnopyranoside (9), and kaempferol-3-O-α-l-rhamnopyranoside (10) were isolated from the ethyl acetate extract of fresh fruits of Amelanchier arborea. The compounds were isolated and purified by various chromatographic techniques and characterized by NMR and GC/MS methods. The isolated compounds inhibited lipid peroxidation (by 85%) at 100 ppm when compared to 89%, 87%, and 98% for the commercial antioxidants butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), and tert-butylhydroxyquinone (TBHQ) at 1.67, 2.2, and 1.67 ppm, respectively. Although not selective, some of these compounds inhibited cyclooxygenase (COX)-1 and -2 enzymes. Compounds 36 were isolated for the first time from A. canadensis and compounds 710 were isolated for the first time from A. arborea fruits.  相似文献   

7.
Raw and deep fried chicken nuggets containing various levels of ganghwayakssuk ethanolic extract (GE) in combination with ascorbic acid (Aa) were evaluated for shelf-life during refrigerated storage (4 °C). The pH and color (lightness, redness, and yellowness) values of raw and deep fried samples were significantly affected by the addition of GE (P < 0.05). All antioxidant combinations except for Aa + GE 0.01 were effective at delaying lipid oxidation (CD, POV, and TBARS) when compared to the control or Aa. Raw samples with GE 0.2 and Aa + GE 0.1 exhibited lower bacterial populations during storage. The sensory characteristics (color, juiciness, flavor, tenderness, and overall acceptability) did not differ significantly in all deep fried chicken nugget samples, except color, whereas storage time had a significant effect (P < 0.05). The results suggest the possibility of utilizing raw and deep fried chicken nuggets with a mixture of ganghwayakssuk and ascorbic acid for the increase of shelf-life and quality.  相似文献   

8.
Fresh flowers, leaves, stems and roots of Echinacea purpurea were subjected to vacuum freeze-drying, cool wind-drying (30 °C), and hot air-drying (40, 55 or 70 °C), and then stored under different environmental conditions. The cichoric acid was the main phenolic compound detected in dried E. purpurea materials, followed by caftaric acid. The bioactive constituent contents in different plant parts were in the descending order: flowers > leaves > stems > roots. Both caffeic acid derivatives and total phenolics contents were affected by drying method and storage condition. Cool wind-dried materials retained more bioactive constituents content (>85%) compared to vacuum freeze-dried materials. The packing material also affected the storability of E. purpurea materials. The storability results indicated that the freeze-dried E. purpurea materials sealed in polyethylene terephthalate/aluminum foil/polyethylene or nylon/polyethylene bags and stored under 10–20 °C and 40–60% relative humidity without light conditions retained the highest content of bioactive compounds.  相似文献   

9.
Eleven blackcurrant cultivars grown with pesticide (PT) and without pesticide treatment (PF) were evaluated to compare the differences in plant growth and physical condition, total anthocyanin content, ascorbic acid content, total antioxidant capacity, effect on prostaglandin E2 (PGE2) production and anticancer cell proliferation activities. Results showed that the yield and growth of PT blackcurrants were higher. However, PF blackcurrants contained a higher amount of ascorbic acid, and displayed an increased inhibition against cancer cells compared to PT blackcurrants, indicating that PF blackcurrants have an increased potential to deliver health-promoting benefit for consumers. Significant differences were observed between blackcurrant cultivars in relation to plant growth and physical condition, total anthocyanin content and PGE2 assay, highlighting the importance of cultivar selection.  相似文献   

10.
The potential of visible (VIS) spectroscopy for screening cadmium and lead contents in the mussel Mytilus galloprovincialis Lmk. was assessed. The spectra of the samples were recorded (400–700 nm). The Cd and Pb contents were determined by graphite furnace atomic absorption spectroscopy, and were regressed against different spectral transformations by modified partial least square (PLSm) regression. Coefficients of determination in the cross-validation (Cd = 0.95; Pb = 0.77) were indicative of equations with excellent and good quantitative information, respectively. The standard deviation to standard error of cross-validation ratio (Cd = 4.43; Pb = 2.10) showed sufficient predictive accuracy for the equations to be used for screening purposes. PLSm loading plots corresponding to the first terms of the equations showed that chromophores influenced them significantly. This pioneering use of the VIS spectrum to predict Cd and Pb in mussels represents an important saving in time and cost of analysis in comparison to other methods.  相似文献   

11.
The protein quality of protein isolates from lupin (LPI) (Lupinus albus var. multolupa), prepared by isoelectric precipitation, was assessed by chemical analysis of protein and amino acids and biological analysis of digestive and metabolic utilization of protein by growing rats. The animals were fed isonitrogenous and isocaloric diets adjusted to meet their nutrient requirements, in which lupin protein isolate was the only protein source, complemented with 0.5% methionine. Different LPIs were prepared with addition, or not, of ascorbic acid as antioxidant. Protein isolates had a protein content of 87.8–98.1%. Manganese content of protein isolates was reduced by 72.8–89.5% compared to the raw seed flour. Results from in vivo experiments showed that addition of 0.5% ascorbic acid to LPI incorporated into diets led to a 82.8% increase in daily food intake, when compared to the non-supplemented LPI, reaching similar values to those obtained with a casein–methionine control diet. Digestive and metabolic utilization of protein from LPI, assessed by nitrogen absorption or apparent digestibility coefficient, and by nitrogen balance or percentage of retained to absorbed nitrogen, respectively, was high, when the dietary intake of animals fed the LPI diets was adequate after addition of 0.5% ascorbic acid, although slightly inferior to the values obtained with a casein–methionine control diet. The high nutritive utilization of protein was reflected in excellent growth and nutritional indices assayed. In conclusion, ascorbic acid supplementation led to an improvement in the palatability of the LPI diets and, therefore, in daily food intake, which was reflected in a higher nutritive utilization of protein and improvement in weight gain and the food transformation index.  相似文献   

12.
The antioxidant activity of methanol extracts from Passiflora edulis and Passiflora alata pulp, and P. edulis rinds, healthy or infected with the passion fruit woodiness virus (PWV), was investigated using the oxidant activities of the neutrophil and the neutrophil granule enzyme myeloperoxidase (MPO), both playing key roles in inflammation. The reactive oxygen species produced by stimulated neutrophils were evaluated by lucigenin-enhanced chemiluminescence (CL) and the activity of purified MPO was measured by SIEFED (Specific Immunological Extraction Followed by Enzymatic Detection), a technique for studying the direct interaction of a compound with the enzyme. The rind extracts of P. edulis possessed higher and dose-dependent inhibitory effects on CL response and on the peroxidase activity of MPO than total pulp extracts from both passion fruit species. The quantification of isoorientin in the extracts showed a correlation with their antioxidant activity, suggesting the potential of P. edulis rinds as functional food or as a possible source of natural flavonoids.  相似文献   

13.
Critical steps of a typical industrial line for processing a blackberry-based beverage in glass bottles have been studied, together with the effects of storage of final product at four different temperatures. For the steps, contents of total phenolics, anthocyanins, ellagitannins, and minor phenolic compounds were assessed by HPLC-DAD and antioxidant capacity by H-ORAC and DPPH. Thermal processes, especially blanching, drastically reduced anthocyanins, whereas hot-filling degraded ellagitannins. The final product showed reduced values for the anthocyanins cyanidin-3-glucoside (by 52%) and cyanidin-3-malonyl glucoside (64%), and ellagitannins lambertianin C (80%), and sanguiin H-6 (50%). Antioxidant capacity (H-ORAC) dropped by almost 47%. The anthocyanins and ellagitannins continued degrading during storage, especially if temperatures were high. Reduction kinetic parameters during storage were estimated for anthocyanins and, for the first time, for both lambertianin C and sanguiin H-6.  相似文献   

14.
Nopal (Opuntia ficus-indica) is an endemic plant of the arid and semiarid lands of America. Preservation problems are associated with nopal utilization and processing, so a practical alternative is dehydration. This work deals with the drying of nopal correlated with the textural properties of the dried product. Convective drying studies were performed and the most representative experimental results at two air flow rates (3 and 5 m/s) and two air temperatures (45 and 65 °C) are displayed here. Experiments of osmotic drying with glucose at 40 and 60 °Brix, and drying temperatures of 25 and 45 °C were tested. A combination of both drying processes was also performed. Results have shown forced convection drying with a mostly decreasing trend at the constant rate period. In the osmotic drying, moisture loss was associated to glucose concentration. Texture profile analysis of dehydrated nopal suggested that samples undergoing convective drying have more cohesiveness than samples treated solely by osmotic drying. On the other hand, samples treated by osmotic drying became more elastic. Between the two drying methods studied, the convective drying has shown the best results at the experimental conditions assayed.  相似文献   

15.
The antioxidant activity of extracts of the stems, leaves, and roots of Echinacea purpurea was compared with the antioxidant activity of purified cichoric acid and alkamides, both constituents of Echinacea purpurea. The antioxidant activity was determined using different methods: effect on oxygen consumption rate of a peroxidating lipid emulsion, and scavenging of radicals, i.e. 2,2-diphenyl-1-picrylhydrazyl (DPPH), measured by two different techniques. The efficacy of the extracts in the reaction with DPPH correlated well with the amount of cichoric acid present in the various extracts. The alkamides alone showed no antioxidant activity in any of the tests. Alkamides present in the extract increased, however, the antioxidative effect of cichoric acid in the peroxidating lipid emulsion. The activity was further compared with that of rosmarinic acid, a well-characterised antioxidant, and the extracts as well as cichoric acid were found to be efficient scavengers of radicals with an activity comparable to that of rosmarinic acid. Cichoric acid was found to have a stoichiometric factor of 4.0 in scavenging DPPH and to react in a second-order reaction with DPPH with a rate constant of 40 l/mol/s at 25 °C in methanol.  相似文献   

16.
In order to establish an effective freezing method for quality control, the present research evaluated the effects of the different freezing treatments on the quality of Japanese sea bass (Lateolabrax japonicas) over a period of 20 days storage at 0 ± 1 °C. Fish pH value, total volatile basic nitrogen (TVB-N), K-value, trimethylamine nitrogen (TMA-N), drip loss, hardness, color, biogenic amines, microbiological characteristics were measured. Sea bass fillets were stored at −18 °C (T1), −55 °C for 24 h and then −18 °C (T2), −55 °C (T3) for 3 months prior to refrigerated storage. T2 showed lower TVB-N, pH value, biogenic amines and drip loss than T3 and T1 did. Significant lower value of bacterial loads, b* value and hardness were observed in T1, T2 and T3 than those of control group. No significant differences were observed among T1, T2 and T3 for TMA-N and a* value. The study demonstrated that Japanese sea bass fillets treated with −55 °C for 24 h and then −18 °C up to 3 months maintain better quality during refrigerated storage.  相似文献   

17.
This study was conducted in order to assess the effect of the inoculation of Glycine max (soybean) with Bradyrhizobium japonicum on the metabolite profile and antioxidant potential of its aerial parts. Extracts containing phenolic compounds and organic acids were analysed by HPLC–DAD and HPLC–UV, respectively. Volatiles profile was determined by HS-SPME/GC–IT-MS. The antioxidant activity of acidic and methanolic extracts was assessed against DPPH. Nodulation caused by B. japonicum led to an increase in the contents of phenolic compounds and organic acids. The same was observed for volatile compounds, with compounds like linalyl acetate, menthyl acetate and α-farnesene being detected only in inoculated plants. The phenolic extracts showed stronger antioxidant capacity than the organic acid extracts. In addition, extracts from plants nodulated with B. japonicum exhibited significantly higher antioxidant activity than control samples. These findings suggest that the inoculation with nodulating B. japonicum strains may be employed to manipulate the content of interesting metabolites in G. max aerial parts.  相似文献   

18.
The CIE-LAB coordinates, total phenols, betalains and vitamin C were determined in berry cactus fruit at different maturity stages, before and after storage. The contribution of those antioxidant compounds to the Trolox equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity (ORAC) were assessed as well. The simple phenolics profile was determined by high performance liquid chromatography with diode array detection (HPLC-DAD). After storage, the fruit develops similar colour compared to ripe and overripe fresh fruit. Total phenols and vitamin C were reduced by up to 82.4% and 68.5%, respectively, as fruit matures and after storage. On the contrary, beta-cyanins increase up to 51.8% as fruit matures and after storage. Betalains contribute with 58.4% to TEAC and up to 43.4 to ORAC values. Gallic acid and quercetin were the major simple phenolics present. Due to the contents of antioxidant compounds and the outstanding antioxidant activities, cactus berries could contribute to health.  相似文献   

19.
The lipid profile and fatty acid composition of muscle, liver, and plasma lipoprotein were examined in wild and cultured Japanese eel (Anguilla japonica). Although, the muscle lipid levels of wild eels (11.6%) were less than those of cultured eels (13.1%), both eels were classified as typical fatty fish. Compared with the liver lipid composition of cultured eels, triacylglycerol (TG) level of the liver decreased in wild eels, whilst phosphatidylcholine and phosphatidylethanolamine levels of the liver increased in wild eels, reflecting the difference of liver lipid levels in both eels. Wild eels contained more cholesteryl ester (CE) and less TG, phospholipid, and free cholesterol in their plasma than cultured eels. The ratio of TG to CE decreased, whilst that of CE to total cholesterol increased in the plasma of wild eels. Different fatty acid compositions were found between wild and cultured eels. Compared with the fatty acid compositions of cultured eels, wild eels contained high percentages of 18:2, 18:3, and 20:4 and low percentages of 22:6, 20:1, and 20:5 in their muscle, liver, and plasma lipoprotein. The lipid profile and fatty acid composition seemed to be useful criteria for distinguishing between wild and cultured eels.  相似文献   

20.
In this study, the effects of cold storage, rearing temperature, parasitoid age, and irradiation on the performance of the egg parasitoid Trichogramma evanescens were investigated. Pupae of T. evanescens can be stored at 4 °C for up to 3 weeks without much loss of performance. The longevity and walking speed of adults emerging from chilled pupae significantly decreased after longer storage periods. The F1 generation of adults which emerged from pupae stored up to 3 weeks was able to parasitize as well as the control. The parasitization rate was similar at 24, 27, and 30 °C, but significantly decreased at 33 and 36 °C. Although T. evanescens developed to the pupal stage at 36 °C, no adult emergence was observed at this temperature. Developmental periods were longer at 24 °C than at higher temperatures. The optimum age for T. evanescens to successfully parasitize host eggs ranged from 24 to 90 h. The parasitization frequency of the 56-78 h aged females was higher than for the other age groups. The daily egg laying pattern of female T. evanescens adults was similar when they were reared on Ephestia kuehniella or Plodia interpunctella eggs. Gamma- or ultraviolet-irradiated and unirradiated host eggs were equally preferred by adult females.  相似文献   

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