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1.
The distribution of the pyrimidinone glucopyranosides vicine and convicine was investigated in resting seed and axenic developing seedlings up to 17 days of age in Vicia faba cv Troy, a low seed pyrimidinone glucopyranoside mutant (MTG5) derived from Troy, and a related species V narbonensis. The lower amounts of total vicine and convicine in resting seed of MTG5 were due primarily to a reduction in cotyledon pyrimidinone glucopyranosides, with the amount in the embryo axis much less affected. Distribution within developing seedlings revealed consistent patterns. A pulse of vicine appeared in both species in stems and roots at day 4 to day 7, then declined. Amounts of convicine rose initially then declined in seedling stems of both species, whereas in roots the rise in convicine continued throughout the period. The rise in convicine in the roots of V narbonensis could not have been accounted for by conversion from reserves of vicine. The low pyrimidinone glucopyranoside mutant MTG5 had less vicine initially in stems and roots than both Troy and V. narbonensis but by 17 days this had risen close to the levels of Troy and exceeded those of V narbonensis. By flowering, amounts of vicine and convicine in glass-house grown plants were similar in MTG5 and Troy. The levels of both compounds in the roots of MTG5 exceeded those of the sown seed. Consequently, both V faba and V narbonensis have the capacity to synthesise vicine and convicine in young plants. A mutation in a gene controlling levels of pyrimidinone glucopyranosides in the developing seed of V faba does not suppress the biosynthetic ability of young plants. 相似文献
2.
3.
Improving significantly the acylation reaction of l-carnitine with conjugated linoleic acid catalyzed by lipase needs to select an efficient and suitable reaction medium that
is not only polar but also hydrophobic. [Bmim]PF6 which is satisfied with the above two requirements was applied as the reaction medium. The optimal reaction conditions were:
Novozyme 435 as the catalyst, 5:1 of molar ratio of fatty acid to l-carnitine, 40 g L−1 lipase, 0.22 aW of initial water activity, 125 g L−1 molecular sieves (they were added within 0–3 h of reaction time), 60 °C of reaction temperature, 200 rpm of rotation speed,
32 h of reaction time. The overall conversion could reach 98.27%. The conversion in [Bmim]PF6 was 2.13 and 1.56 times higher than that in acetonitrile and in solvent-free system, respectively. The lipase in the present
work could be used eight times. [Bmim]PF6 as the reaction medium was better than acetonitrile and solvent-free system. 相似文献
4.
Jalal Jamalian 《Journal of the science of food and agriculture》1999,79(13):1909-1914
Ingestion of fababeans is associated with precipitation of the haemolytic disease favism in certain glucose-6-phosphate dehydrogenase-deficient humans. Hence their incorporation into weaning foods has not yet been practised. Few, if any, attempts to detoxify fababeans have so far been made. The present investigation has evaluated the effects of a series of treatments designed for vicine and convicine extraction and hydrolysis followed by oxidation of their pyrimidine moieties (divicine and isouramil). The effects of seed germination and oxidative treatment by hydrogen peroxide have also been examined. Extracts of treated samples were assayed for residual vicine and convicine. Toxicity was monitored by the changes in vitro of reduced glutathione (GSH) of red blood cells (RBCs) from Sprague Dawley rats deliberately made deficient in glutathione reductase activity to mimic favism-susceptible human RBCs. Treatments of whole cotyledons resulted in recovery of 59–93% vicine and 50–70% convicine originally present in the seeds. Treatments of fababean powders, however, were capable of lowering the vicine content by 94–100% and convicine content by 100%. Germinated seeds showed a drop in vicine content of 86% and their hydrogen peroxide treatment 91–93%. Convicine was totally absent in germinated and oxidised seeds. The results of toxicity assays were concomitant with vicine and convicine analyses. Protein content of original fababean powders was well recovered (up to 94.00%) and its digestibility was almost complete (99.34%). © 1999 Society of Chemical Industry 相似文献
5.
Serap Doğan Mehmet Emin Diken Yasemin Turhan Ümran Alan Mehmet Doğan Mahir Alkan 《European Food Research and Technology》2011,233(2):293-301
Polyphenoloxidase (PPO) from Rosmarinus officinalis L. was fractionated by ammonium sulfate ((NH4)2SO4) precipitation and dialysis, and then some of its kinetic properties such as optimum pH and temperature, substrate specificity,
thermal inactivation, and inhibition were investigated using 4-methylcatechol, catechol, and pyrogallol as substrates. The
protein content of Rosmarinus officinalis L. extracts was determined according to Bradford’s method. Kinetic parameters, K
m and V
max, were calculated from Lineweaver–Burk plots. According to V
max/K
m ratio, 4-methylcatechol was the most suitable substrate. The optimum temperature and pH values were 20, 30 and 30 °C, and
7, 8 and 8 for 4-methylcatechol, catechol, and pyrogallol substrates, respectively. The thermal inactivation of PPO was investigated
at 35, 55, and 75 °C. The enzyme activity decreased with increasing temperature. The effect of different inhibitors on partly
purified Rosmarinus officinalis L. PPO was spectrophotometrically investigated. For this purpose, ascorbic acid and l-cysteine were used to inhibit the activity of Rosmarinus officinalis L. PPO at different concentrations. From the experimental results, it was found that l-cysteine is a more effective inhibitor than ascorbic acid due to lower K
i values. 相似文献
6.
Jadwiga Sadowska Jarosław Budny Józef Fornal 《European Food Research and Technology》2008,227(1):233-241
Changes in contents of protein, starch, ash, l-ascorbic acid, and glycoalkaloids in tubers of 15 clones of cultivar Irga transformed with viral genome sequences in order
to improve their resistance to a necrotic strain of potato virus Y (PVYN) were investigated. The influence of modification type and year of cultivation on the contents of all chemical compounds
examined for particular modified clones appeared to be irregular over the 3-year period of examination, and the clone of the
best and stable content of chemical compounds was not found. Stable tendencies in the chemical compounds of tubers composed
into groups and subgroups of clones representing the same modification type were not confirmed either. An essential stable
decrease in glycoalkaloid content and an increase in starch content (compared with parental cultivar Irga) were found in almost
all genetically modified clones. Glycoalkaloid content in green tubers of modified clones was usually (except three clones)
higher than this for parental cultivar Irga. Correlation between glycoalkaloid content and tuber size for all, normal and
green tubers of selected clones and parental cultivar Irga was examined as well. 相似文献
7.
The histidine decarboxylating activity and production of biogenic amines by Morganella morganii (NCIMB, 10466), Klebsiella pneumoniae (NCIMB, 673) and Hafnia alvei (NCIMB, 11999) were investigated using a rapid HPLC method. Derivatisation of the bacterial samples was carried out using benzoyl chloride. A gradient elution system was used for analysis with a mixture of acetonitrile and HPLC grade water. Bacterial strains not only produce histamine in histidine-enriched broth but also the other biogenic amines. The chromatographic results show that bacterial strains are also capable of producing spermine and spermidine in histidine-enriched broth. Bacterial ammonia production by all three strains was clearly detected since ammonia is generated during the degradation of histidine. The study demonstrates that the highest histamine production was obtained by Morganella morganii, followed by Klebsiella pneumoniae, and the lowest with the Hafnia alvei. Therefore, Morganella morganii and Klebsiella pneumoniae have strong histidine decarboxylase activity since they are prolific histamine-forming bacteria 相似文献
8.
Sencer Buzrul Hami Alpas Alain Largeteau Gérard Demazeau 《European Food Research and Technology》2008,227(2):443-448
The survival curves of Escherichia coli and Listeria innocua inactivated by high hydrostatic pressure (HHP) were obtained at room temperature (∼22 °C) and at five pressure levels (400,
450, 500, 550 and 600 MPa) in whole milk. These curves were described by the Weibull model and parameters of this model were
reduced from two to one with slight loss of goodness-of-fit. The logarithm of the time constant parameter (δ) of the reduced Weibull model was described with respect to high pressure (P). This approach can be used to define a z
p
value analogous to the modeling of the classical D value (increase in pressure that results in one log unit decrease of δ values). The development of accurate survival models under high pressure, as presented here, can be very beneficial to food
industry for designing, evaluating and optimizing HHP processes as a new preservation technology. 相似文献
9.
Juan Liu Bing Gu Jun Bian Shuigen Hu Xi Cheng Qiangkun Ke Huifang Yan 《European Food Research and Technology》2008,227(3):919-924
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
10.
A specific method of analysis for each of the pyrimidine glucosides, vicine and convicine, is described. This involves extraction by ethanol, evaporation, separation on t.l.c. and quantitative ultraviolet spectrophotometry. Using this method mature dehulled fababeans were shown to contain on average 0.73% vicine and 0.30% convicine on a dry matter basis. No significant variation was found between varieties. The glycosides seem to be associated to the protein bodies in the raw bean, and are absent from the hull. The total content of vicine + convicine in isolated fababean proteins ranged from 0.07 to 2.0%. The highest content was found in a protein fraction produced by air-classification of dry milled fababeans. The lowest content was found in proteins isolated from a watery extract either by precipitation with acetic acid or by diafiltration. Protein isolates produced by direct ultrafiltration have contents of about 0.60%. The ratio vicine:convicine was found to be relatively constant in the raw beans (average 2.5), but varied from 1.4 to 3.0 in the protein isolates, thus indicating a different reaction of vicine and convicine to conditions during the processing of the fababean. It is the opinion of the authors that the etiology of favism is still controversial as far as vicine and convicine are concerned. 相似文献
11.
Elena G. Kovatcheva-Apostolova Milen I. Georgiev Mladenka P. Ilieva Leif H. Skibsted Anja Rødtjer Mogens Larsen Andersen 《European Food Research and Technology》2008,227(4):1243-1249
Ethanolic extracts of plant cell cultures of lavender (Lavandula vera) and rose (Rosa damascena) have been examined as potential food antioxidants. The L. vera cell extract quenched the radicals Fremy’s salt, DPPH (2,2-diphenyl-1-picrylhydrazyl radical), and ABTS·+ (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic) radical) more efficiently than the R. damascena extract. Also the L. vera extract inhibited lipid oxidation in a methyl linoleate emulsion more efficiently than the R. damascena extract. However, the L. vera extract had a prooxidative effect on the iron-based Fenton reaction in an aqueous model system. A similar effect was observed
for pure rosmarinic acid, but not for the R. damascena extract. The addition of L. vera extract to minced chicken meat reduced lipid oxidation (measured as thiobarbituric acid reactive species) and the loss of
α-tocopherol during cold storage after the meat was cooked. This suggests the antioxidative properties of L. vera extracts dominate in a real food system. 相似文献
12.
The purpose of the present study was to evaluate small and high molecular phenolics (tannins) and antioxidant activity of
Aronia melanocarpa berries, juice and pomace in order to find new potential sources of natural antioxidants. The fruits of Aronia melanocarpa Elliot were collected in the middle of October at a plantation near Wroclaw, Poland. The pomace has a much higher content
of phenolics in comparision to juice and fruits. Results showed that polymeric proanthocyanins, predominantly of (−)epicatechin,
are the major class of polyphenolic compounds in chokeberry, represent 66% of fruits polyphenols. The average concentration
ranged from 1578.79 mg/100 g of DW for chokeberry juice up to 8191.58 mg/100 g in pomace. The concentration of phenolic acids
(chlorogenic and neochlorogenic acids) in juice was higher than in pomace. Anthocyanins in Aronia melanocarpa are second phenolic compound group and represent about 25% of total polyphenols, mixture of four different cyanidin glycosides:
3-galactoside, 3-glucoside, 3-arabinoside and 3-xyloside. The higher antioxidant activity expressed as TEAC was measured in
pomace >fruit >juice. 相似文献
13.
Isabel López Carmen Torres Fernanda Ruiz-Larrea 《European Food Research and Technology》2008,227(2):547-555
Genetic typification of 120 bacterial isolates of Lactobacillus plantarum and Oenococcus oeni from different Rioja musts and wines was performed by numerical analysis of pulsed-field gel electrophoresis (PFGE) patterns
with endonuclease SfiI, and 46 of them were also studied by randomly amplified polymorphic DNA (RAPD)-PCR. A comparative study of both typification
methods applied to L. plantarum and O. oeni oenological strains was performed. Bacterial species was determined both by biochemical identification methods and by specific
PCR analysis. A wide variety of restriction digest patterns were detected by PFGE among L. plantarum strains (36 unrelated patterns and one closely related pattern, out of 48 isolates), as well as among O. oeni strains (18 unrelated patterns out of 72 isolates). PFGE was shown to be a suitable method for strain differentiation and
to determine which strains are present in wine fermentations, with a discriminatory power to type L. plantarum and O. oeni strains higher than that of RAPD-PCR. 相似文献
14.
Fatty seeds of Papaver somniferum and Corylus avellana undergo a rapid microbial degradation after being ground. Those bacteria and fungi which are mainly responsible for the microbial decay were identified, and the most important growth and death processes were documented using crucial indicator-organisms. Additionally, an aflatoxin-screening was carried out in order to assess the possible risk-potential of food intoxication. The acid value (indicator for free fatty acids) of poppy seeds and hazelnut kernels was determined during their fermentation in order to document the decomposition of triglycerides.In this study it could be proved that initially a natural decay of oil seeds is caused by bacteria, yeasts and mould fungi. After the bacteria died in the course of time, yeasts and mould fungi dominated the germ spectrum. Bacteria taking part in the degradation were identified as varieties of Staphylococcus xylosus, Enterobacteriaceae and coliforms. Yeasts were identified as Pichia burtonii, and the mould fungi are associated with the genus Alternaria.On account of the absence of the genus Aspergillus in the spectrum of mould fungi, no aflatoxin was produced. 相似文献
15.
Rihua Xu Qian Shen Xuelong Ding Wengeng Gao Pinglan Li 《European Food Research and Technology》2011,232(2):231-240
The major exopolysaccharide fraction (EPSa) of Bifidobacterium animalis RH was purified to illustrate the chemical characterization and the antioxidant activity in vitro. The molecular weight of
EPSa was 2.31 × 104 Da determined by the gel permeation chromatography (GPC). Fourier-transform infrared spectra (FT-IR) and the monosaccharide
analysis of high-pH anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) showed that it was a heteropolysaccharide
mainly composed of d-glucose, d-mannose, d-galactose, l-arabinose, d-fructose, and l-rhamnose in molar ratios of 43:34:18:4:1:1. In antioxidant assays, the EPSa had a higher activity for antilipid peroxidation
and a stronger scavenging activity of hydroxyl radical and superoxide radical than ascorbic acid. It also had a similar α,α-diphenyl-β-picrylhydrazyl
(DPPH) radical-scavenging activity with ascorbic acid at low concentration and had concentration-dependent inhibitory ability
on erythrocyte hemolysis. These results indicated that the EPSa fraction had strong antioxidant activities and could be explored
as novel potential antioxidants. 相似文献
16.
Prashani Mudika Ekanayake Chamilani Nikapitiya Mahanama De Zoysa Ilson Whang Se Jae Kim Jehee Lee 《European Food Research and Technology》2008,227(3):897-903
Natural fermentation was tested as a method of releasing active compounds during screening for potential anticoagulant activity
in three types of algae (Pachymeniopsis elliptica, Sargassum horneri, and Ulva pertusa). Freeze dried algae samples (2.5 g) were fermented by adding 75 g of sugar and 500 mL of water and thereafter kept at room
temperature (25 °C) for 3 months. Activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT)
were measured every 2 weeks for 3 months to determine the optimum time for the highest activity. Fermented P. elliptica, (which had the highest activity) was subjected to anion exchange chromatography (DEAE-cellulose) and sepharose 4B gel permeation
chromatography. The purified sample was analyzed by agarose-gel electrophoresis and polyacrylamide gel electrophoresis (PAGE)
to confirm the purification and to determine the molecular mass, respectively. The 360 μg/mL of purified compound (Mwt > 500,000 Da)
had both APTT and PT activities (>1,000 s). However, at the concentrations of 180 μg/mL, purified compound and heparin showed
540 and >1,000 s APTT activity, respectively. Though, the purified compound of P. elliptica considered as a weaker anticoagulant than heparin, this purified anticoagulant polysaccharide could be considered as a good
alternative source as an anticoagulant. Moreover, the technique of fermentation is an inexpensive and feasible, this purified
anticoagulant polysaccharide compound could be used in pharmaceutical and biomedical industry. Further investigations need
to be performed to determine the mechanism of this novel anticoagulant compound.
The authors Prashani Mudika Ekanayake and Chamilani Nikapitiya contributed equally to this work. 相似文献
17.
The ability of Rhizopus chinensis lipase (Thermo 4S-3) to catalyze the deacylation of l,2-diacyl-sn-glycero-3-phosphocholines (sn-1,2-PC) for l-alpha glycerylphosphorylcholine (l-α-GPC) preparation was investigated. Response surface methodology (RSM), based on a modified central composite rotatable
design, was employed to examine the effects of substrate concentrations, temperature, enzyme loading, and dosage of CaCl2 on the l-α-GPC yield. RSM analysis indicated good correlation between experimental and predicated values. The optimal condition was
confirmed as follows: reaction time, 3.5 h; temperature, 43 °C; enzyme loading, 28.2 U mL−1; substrate concentration, 51.5 mg mL−1; and dosage of CaCl2, 1.9 mg mL−1. Under these conditions, the l-α-GPC yield increased by 96.8%, which was close to the amount predicted by the model. 相似文献
18.
Dioscorea batatas Decne (DBD) has been traditionally used as folk medicine and health food in Korea. One glycoprotein was isolated from DBD
and confirmed to have 30 kDa molecular weight. The DBD glycoprotein was tested its antioxidative activity and characterized
in various chemical conditions. The DBD glycoprotein has the optimal free radical scavenging activities in acidic and neutral
pH and up to 85 °C. In the M2+ ions (Ca2+, Mn2+, and Mg2+) in the presence of EDTA, the activities of DBD glycoprotein reduced, compared to DBD glycoprotein alone without metal ion.
Interestingly, the results in this study indicated that the activities of DBD glycoprotein do not depend on the presence of
EDTA. Interestingly, when DBD glycoprotein was treated with deactivation agents (pronase E or NaIO4), scavenging activity of DBD glycoprotein was decreased. The anti-oxidative effects of DBD glycoprotein on hydroxyl radicals
in cell-free system revealed, and the DBD glycoprotein has remarkable scavenging effects on hydroxyl radicals generated by
G/GO. Furthermore, the results in this study showed that the DBD glycoprotein (200 μg/ml) significantly inhibits intracellular
ROS amounts and protects from cytotoxicity in primary mouse splenocyte culture treated with GO (30 mU/ml). Therefore, we speculate
that DBD glycoprotein has an antioxidative potential as one of natural antioxidants. 相似文献
19.
Sencer Buzrul Hami Alpas Alain Largeteau Gérard Demazeau 《European Food Research and Technology》2009,229(1):127-131
Escherichia coli ATCC 11775 and Listeria innocua ATCC 33090 in whole milk were inactivated by single- and multi-pulsed (up to 10 pulses) high hydrostatic pressure (HHP) treatments.
Both bacteria showed similar resistance to single- and multi-pulsed HHP. The efficiency of pulsed pressure treatment depends
on the combination of holding time of each pulse and number of pulses. It was observed that multi-pulsed pressure treatment
instead of traditional single-pulsed HHP could be used to pasteurize milk at a lower pressure level. Nevertheless, an optimization
is necessary between the pulse holding time, number of pulses, and pressure levels to reach the desirable log-reduction of
microorganisms compatible with industrial application.
This study was partly presented in Joint 21st AIRAPT and 45th EHPRG International Conference on High Pressure Science and
Technology held September 17–21, 2007 in Catania (Italy). 相似文献
20.
The influence of a Lactobacillus plantarum (B4) on the growth of Staphylococcus aureus (Sa4) was verified by impedometric methods in a suitable model reproducing the characteristics of fresh vegetables. The inoculum size of the single strains and their growth temperature were varied according to a Central Composite Design. The results obtained via statistical analysis showed that the temperature affected the growth of both S. aureus and L. plantarum strains. The pathogenic strain, independently of its inoculum size, was inhibited by L. plantarum at all the tested temperatures. A proper combination of specific lactic acid bacteria and storage temperature should improve the safety of the vegetable products. 相似文献