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1.
The effects of different preservation times (cuttlefish auction), transformation factory treatments, different times of frozen storage at −20 °C and various defrosting temperatures were investigated with respect to the chemical changes of the viscera of cuttlefish (Sepia officinalis). During auction storage, pH and TCA (trichloroacetic acid)-soluble protein concentration decreased, whereas intracellular (cathepsins, total acid proteases and acid phosphatases) and extracellular (amylase, chymotrypsin, trypsin and total alkaline proteases) enzymatic activities increased. In cuttlefish transformation factories, pH value and TCA-soluble protein concentration increased. In transformation factory conditions, lipase and amylase levels varied, while other assayed enzymes were stable. Moreover, during transformation factory treatment, the molecular weight of proteins/peptides decreased and the oil composition evolution reflected hydrolysis of cuttlefish viscera. Thus, cuttlefish viscera fatty acid composition differed between fresh viscera and factory viscera. Despite changes in the fatty acid chain composition during factory transformation, the percentage of poly-unsaturated fatty acids remained high. Frozen storage implied major changes in viscera quality such as an increase in pH and a decrease in the quantity of high molecular weight protein. Moreover, the higher the defrosting temperature, the higher was the pH. During storage at −20 °C the quantities of proteins, carbohydrates and lipids decreased slightly.  相似文献   

2.
The total lipids and seasonal variations in the fatty acids of the mantle of cuttlefish (Sepia officinalis) captured in the north eastern Mediterranean were investigated and the mantle was found to be a good source of polyunsaturated fatty acids (ω3 PUFAs, in particular). In all seasons, the major fatty acids in the cuttlefish mantle were observed to be palmitic acid (16:0), stearic acid (18:0), eicosapentaenoic acid (EPA, 20:5ω3) and docosahexaenoic acid (DHA, 22:6ω3). A comparison of the saturated fatty acid (29.5–36.8%), monounsaturated fatty acids (7.81–9.84%) and polyunsaturated fatty acids (43.7–49.6%) of the cuttlefish mantle revealed that polyunsaturated fatty acids (PUFA) constituted the highest proportion. The levels of DHA in the cuttlefish mantle in autumn, winter, spring and summer were 27.6%, 28.5%, 29.5% and 23.9%, while those of EPA were 16.8%, 15.4%, 14.7% and 13.9%, respectively.  相似文献   

3.
Thermostable trypsin from the hepatopancreas of Sepia officinalis was purified by fractionation with ammonium sulphate, Sephadex G-100 gel filtration, DEAE-cellulose an ion-exchange chromatography, Sephadex G-75 gel filtration and Q-Sepharose anion-exchange chromatography, with a 26.7-fold increase in specific activity and 21.8% recovery. The molecular weight of the purified enzyme was estimated to be 24,000 Da by SDS-PAGE and size exclusion chromatography. The purified enzyme showed esterase specific activity on Nα -benzoyl-L-arginine ethyl ester (BAEE) and amidase activity on Nα -benzoyl-DL-arginine-p-nitroanilide (BAPNA). The optimum pH and temperature for the enzyme activity were pH 8.0 and 70 °C, respectively, using BAPNA as a substrate. The enzyme was extremely stable in the pH range 6.0–10.0 and highly stable up to 50 °C after 1 h of incubation. The purified enzyme was inhibited by soybean trypsin inhibitor (SBTI) and phenylmethylsulphonyl fluoride (PMSF), a serine-protease inhibitor. The N-terminal amino acid sequence of the first 12 amino acids of the purified trypsin was IVGGKESSPYNQ. S. officinalis trypsin, which showed high homology with trypsins from marine vertebrates and invertebrates, had a charged Lys residue at position 5 and a Ser residue at position 7, where Tyr and Cys are common in all marine vertebrates and mammalian trypsins. Further, the enzyme had an Asn at position 11, not found in any other trypsins.  相似文献   

4.
Dried valerian (Valeriana officinalis) root powder was stored at 5, 14 and 30 °C under low, moderate and high humidity conditions for 6 months, and the level of the valerenic acids monitored on a monthly basis. From an initial moisture content of 5 g/kg, the moisture level during storage decreased in root powder stored at low humidity and increased during storage at high humidity, with the effect greatest at 30 °C.  相似文献   

5.
The aim of this study was to investigate the anti-inflammatory effects of the crude extract (CE) of Rosmarinus officinalis L. its derived fractions: hexane (HEX), ethyl acetate (AcOEt), and ethanolic (ET), and isolated compounds: carnosol, betulinic acid and ursolic acid, in the mouse pleurisy model induced by carrageenan. Swiss mice were used in the in vivo experiments. The CE and its derived fractions and isolated compounds inhibited leukocytes, exudation, interleukin-1 beta (IL-1β) and tumour necrosis factor-alpha (TNF-α) levels, myeloperoxidase activity (MPO), and nitrite/nitrate production (NOx) (p < 0.05). R. officinalis L. showed an important anti-inflammatory activity by inhibition not only of leukocytes and exudation, but also of a pro-inflammatory enzyme and mediators (MPO, NOx, IL-1β, and TNF-α). The present study showed that carnosol, betulinic acid and ursolic acid compounds could be responsible for this anti-inflammatory effect.  相似文献   

6.
Rosemary (Rosmarinus officinalis L.) has been used in folk medicine to treat headaches, epilepsy, poor circulation, and many other ailments. It was found that rosemary could act as a stimulant and mild analgesic and could reduce inflammation. However, the mechanisms underlying the anti-inflammatory effects of rosemary need more study to be established. Therefore, in this study, the effects of rosemary on the activation of nuclear factor kappa beta (NF-kB) and mitogen-activated protein kinases (MAPKs), the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and the production of nitric oxide (NO), prostaglandin E2 (PGE2), and cytokine in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells were investigated. A methanol extract of rosemary and its hexane fraction reduced NO generation with an IC50 of 2.75 and 2.83 μg/ml, respectively. Also, the methanol extract and the hexane fraction inhibited LPS-induced MAPKs and NF-kB activation associated with the inhibition of iNOS or COX-2 expression. LPS-induced production of PGE2 and tumour necrosis factor-alpha (TNF-α) were blocked by rosemary. Rosemary extract and its hexane fraction are important for the prevention of phosphorylation of MAPKs, thereby blocking NF-kB activation, which in turn leads to decreased expression of iNOS and COX-2, thus preventing inflammation.  相似文献   

7.
In the current study, we have tested acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity of the petroleum ether, ethyl acetate, chloroform, and methanol extracts, rosmarinic acid as well as the essential oil obtained from Rosmarinus officinalis L. growing in Turkey by a spectrophotometric method of Ellman using ELISA microplate-reader at 0.2, 0.5, and 1.0 mg/mL concentrations. In addition, quantification of rosmarinic acid, a common phenolic acid found in rosemary, was carried out by reversed-phase HPLC in the methanolic extract of the plant, which was found to have 12.21 ± 0.95% (122.1 ± 9.5 mg/g extract) of rosmarinic acid. Rosmarinic acid was also tested for its AChE and BChE inhibitory effect and found to cause 85.8% of inhibition against AChE at only 1.0 mg/mL. Besides, the essential oil was analyzed by GC–MS technique, which was shown to be dominated by 1,8-cineol (44.42%) and followed by α-pinene (12.57%).  相似文献   

8.
Hyssopus officinalis L. (hyssop) as a food ingredient has its own importance in flavor industry and also in sauce formulations. Supercritical fluid extraction (SFE) of hyssop, cultivated in Iran, was performed at various pressures, temperatures, extraction (dynamic and static) times and modifier (methanol) concentrations using an orthogonal array design with an OA25(55) matrix conditions. Pressure, temperature and modifier in the SFE system influenced the extraction yield. Also, the composition of the extracted oils was greatly impacted by the operating conditions. Main components of the extracts under different SFE conditions were sabinene (4.2–17.1%, w/w), iso-pinocamphene (0.9–16.5%) and pinocamphene (0.7–13.6%). The extraction of sabinene, for example, was favored at 100 atm, 55 °C, 1.5% (v/v) methanol, 30 min dynamic time and 35 min static time. Use of SFE under different conditions can allow targeting the extraction of different constituents.  相似文献   

9.
The essential oils of Salvia officinalis and Salvia triloba cultivated in South Brazil were analyzed by GC–MS. The major constituents of the oil of S. officinalis were α-thujone, 1,8-cineole, camphor, borneol and β-pinene, whereas those of S. triloba were α-thujone, 1,8-cineole, camphor, and β-caryophyllene. The essential oils of both species exhibited remarkable bacteriostatic and bactericidal activities against Bacillus cereus, Bacillus megatherium, Bacillus subtilis, Aeromonas hydrophila, Aeromonas sobria, and Klebsiella oxytoca. Moreover, the essential oil of S. triloba efficiently inhibited the growth of Staphylococcus aureus. S. aureus and A. hydrophila growth were drastically reduced even in the presence of 0.05 mg/ml of the essential oil of S. triloba.  相似文献   

10.
In this study, the effects of two blanching conditions on ascorbic acid (AA) and peroxidase (POD) in different segments of asparagus (bud, upper, middle, and butt) were investigated. The blanching treatments were: blanching in water at 70, 80 and 90 °C (WB); microwave heating (900 W, 30 s) followed by water blanching (MW + WB). AA degradation and POD inactivation in all segments of asparagus for both treatments are well described by first-order models. The degradation rate of AA and POD is gradually increased from butt to bud segment of asparagus. In addition, MW pre-treatment could increase the Ea of AA degradation and decrease the Ea of POD inactivation during water blanching of asparagus. Therefore, it is recommended that the different segments of asparagus should be subjected to different blanching times, and MW pre-treatment could be applied for alleviating AA degradation and accelerating POD inactivation during blanching, cooking and pasteurisation in water.  相似文献   

11.
This study was designed to examine the in vitro antioxidant activities of Rosmarinus officinalis L. essential oil compared to three of its main components (1,8-cineole, α-pinene, β-pinene). GC–MS analysis of the essential oil resulted in the identification of 19 compounds, representing 97.97% of the oil, the major constituents of the oil were described as 1,8-cineole (27.23%), α-pinene (19.43%), camphor (14.26%), camphene (11.52%) and β-pinene (6.71%). The oil and the components were subjected to screening for their possible antioxidant activity by means of 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and β-carotene bleaching test. In the DPPH test system, free radical-scavenging activity of R. officinalis L. essential oil, 1,8-cineole, α-pinene and β-pinene were determined to be 62.45% ± 3.42%, 42.7% ± 2.5%, 45.61% ± 4.23% and 46.21% ± 2.24% (v/v), respectively. In the β-carotene bleaching test system, we tested series concentration of samples to show the antioxidant activities of the oil and its main components, whereas the concentrations providing 50% inhibition (IC50) values of R. officinalis L. essential oil, 1,8-cineole, α-pinene and β-pinene were 2.04% ± 0.42%, 4.05% ± 0.65%, 2.28% ± 0.23% and 2.56% ± 0.16% (v/v), respectively. In general, R. officinalis L. essential oil showed greater activity than its components in both systems, and the antioxidant activities of all the tested samples were mostly related to their concentrations. Antioxidant activities of the synthetic antioxidant, ascorbic acid and BHT, were also determined in parallel experiments as positive control.  相似文献   

12.
Durmaz H  Sagun E  Sancak H  Sagdic O 《Meat science》2007,76(1):123-127
Cig kofte is a traditional Turkish food prepared from minced beef, bulgur, onions, garlic and varieties of spices. It is generally consumed within a few hours. However, leftovers can be kept in refrigerator or in room temperature up to 24h until they are consumed. In this study, survival and growth of two Listeria monocytogenes serotypes were investigated in cig kofte during the storage. For this purpose, the prepared samples were separately contaminated with serotypes 1/2b or 4b of L. monocytogenes at the level of 10(4)CFU/g and stored at 4°C and 21°C. L. monocytogenes colonies were counted at the beginning, 3rd, 6th, 12th and 24th hours of the storage. At 4°C, L. monocytogenes 4b significantly increased (P<0.05) from 4.12 to 5.49log(10)CFU/g but L. monocytogenes 1/2b remained constant (P>0.05) during the storage period. At 21°C, both L. monocytogenes 1/2b and 4b increased significantly (P<0.05) from 4.56 to 5.16log(10)CFU/g and from 4.23 to 5.65log(10)CFU/g, respectively. The physicochemical and microbiological characteristics of the cig kofte did not inhibit the growths of L. monocytogenes serotypes during the storage. These results indicated that L. monocytogenes was able to survive and grow in cig kofte at the both storage temperatures of 4°C and 21°C and cig kofte seemed to be a suitable medium for this pathogen.  相似文献   

13.
Greening of witloof chicory is a major quality defect being commonly associated with increased bitterness. The aim of this study was to assess the effect of light exposure during storage on levels of bitter sesquiterpene lactones (SLs) and photosynthetic pigments in leaves and central axes of two cultivars of witloof chicory. For this purpose, witloof chicory packaged in consumer-sized polyamide bags was stored in the dark (8 °C) and under light exposure (8 °C, 4500 lux), respectively, over a period of 11 days. Throughout storage, O2 and CO2 levels in the modified atmosphere were monitored. Levels of six individual SLs, chlorophyll derivatives and β-carotene in leaves and central axes were assessed by HPLC-DAD-MSn and color measurements were carried out applying the CIE L*a*b* system.  相似文献   

14.
Hydroalcoholic extracts obtained from myrtle berries of five different selections were studied to obtain unique clones. During the typical 40 day maceration period, dry matter, pH, colour, and anthocyanins, were analyzed. Variability among myrtle selections was observed both in fresh berries (yield berries/plant, weight of the berries, number and weight of seeds per berry) and in the hydroalcoholic extract physical–chemical characteristics (dry matter, colour intensity, tint and anthocyanins). Reversed-phase high performance liquid chromatography (RP-HPLC) analysis with photodiode array detection (PDA) was used for anthocyanins characterization in myrtle hydroalcoholic extracts. Anthocyanin qualitative composition was the same in all selections, but varied strongly in its total amount. D was the selection with the characteristics most suitable for industrial use.  相似文献   

15.
Commercial essential oils of Thymus vulgaris L., Rosmarinus officinalis L. and Origanum vulgare L. were chemically characterized by GC, GC/MS analyses. The antilisterial activity of the oils, and the sub-lethal concentration of lactic acid were established by the agar-well diffusion method. The bactericidal kinetics of the diluted oils (50 ppm, 100 ppm, 200 ppm and 300 ppm) and their mixtures with 50 ppm of lactic acid were determined by optical density (OD600) measurements. The results suggest that a sub-lethal dose of lactic acid noticeably increased the antilisterial activity, especially of rosemary and thyme oils, but that the synergistic effects were reduced with higher concentrations of oils.  相似文献   

16.
Juniper (Juniperus oxycedrus) is used in European cuisine for its distinguishing flavour. J. oxycedrus ssp. oxycedrus berry and wood essential oils were tentatively identified by GC and GC/MS. Fifty compounds were identified in the berry oil and 23 compounds were identified in the wood oil. The J. oxycedrus ssp. oxycedrus berry oil was characterised by high contents of α-pinene (27.4%) and β-myrcene (18.9%). Other important compounds were α-phellandrene (7.1%), limonene (6.7%), epi-bicyclosesquiphellandrene (2.3%) and δ-cadinene (2.2%) while, in the wood oil, δ-cadinene (14.5%) is a major main component, together with cis-thujopsene (9.2%) and α-muurolene (4.9%). In vitro evaluation of antioxidant activity by the DPPH method showed a significant activity for both oils with IC50 values of 1.45 μl/ml for wood and 7.42 μl/ml for berries. Hypoglycaemic activity was investigated through the inhibition of α-amylase. The results revealed that oil obtained by hydrodistillation from J. oxycedrus ssp. oxycedrus wood exhibits an interesting activity with IC50 of 3.49 μl/ml.  相似文献   

17.
Donghe Lu  Min Zhang  Shaojin Wang  Xiang Zhou 《LWT》2010,43(3):519-494
Salicornia bigelovii Torr. (sea-beans or drift seeds in English, sea-asparagus in Chinese) is an oil-seed plant tolerant to seawater irrigation and perishable with a shelf life of only about 6 days at ambient temperature (25 °C). To provide a potential food supplement, nutritional value of S. bigelovii were determined together with its postharvest quality as affected by storage temperatures (0 °C, 2 °C, 8 °C and 25 °C). Nutritional analyses showed that S. bigelovii contained high vitamins and minerals, which made it an ideal nutritional and diet supplement. Storing S. bigelovii at low temperatures could be a practical technique to extend storage life by reducing the quality degradation. After conducing sensory evaluations and determining ascorbic acid and chlorophyll contents, the optimal temperature for storing S. bigelovii was around 2 °C. This research will help to develop technically effective and energy efficient methods for prolonging the shelf life of S. bigelovii.  相似文献   

18.
Pre rigor produced fillets of Atlantic cod become shorter and more firm than post rigor produced fillets. In pre rigor excised muscle from warm-blooded animals and warm-water adapted fish, cold shortening, extensive contraction during cold storage, is known to occur. The aim of the present work was to study if the extent of fillet shortening in Atlantic cod could be reduced by a slight temperature increase during rigor contraction. The results demonstrate that fillets from this cold-water species showed no cold shortening. On the contrary, the fillets contracted the least when stored at 0 °C during rigor contraction.  相似文献   

19.
Pseudomonas of pallet-packaged raw pork grown at 0, 5, 10, 15, 20 and 25 °C has been studied in this paper. The modified Gompertz, Baranyi and Huang models were used for data fitting. Statistical criteria such as residual sum of squares, mean square error, Akaike's information criterion, and pseudo-R2 were used to evaluate model performance. Results showed that there was an apparent decline in Pseudomonas growth at initial-storage phase at low temperatures. The modified Gompertz model outperformed the others at 5, 15, and 20 °C, while Baranyi model was appropriate for 0 and 25 °C. The Huang model was optimal at 10 °C. No single model can give a consistently preferable goodness-of-fit for all growth data. The Gompertz model, with the smallest average values of RSS, AIC, MSE and the biggest pseudo-R2 at all temperatures, is the most appropriate model to describe the growth of Pseudomonas of raw pork under pallet packaging.  相似文献   

20.
Globe artichoke is an ancient herbaceous plant native to the Mediterranean Basin. The edible part of the plant (head) is particularly rich in polyphenols, whose therapeutic properties are well documented. A field experiment was conducted in Sicily (south Italy) to examine the influence of genotype and harvest time on the polyphenol content and profile of different head parts. The concentrations of 19 phenolic compounds were determined by HPLC-DAD-ESI/MSn analysis. It was observed that individual phenolic substances were preferentially accumulated in specific head parts and genotypes. Apigenin 7-O-glucuronide was found to be the major flavonoid, with 6298 mg kg−1 DM in ‘Romanesco clone C3’ receptacle, whereas chlorogenic acid represented the main caffeoylquinic acid, reaching 14841 mg kg−1 DM in the inner bracts of ‘Violetto di Sicilia’. Our findings prove also the influence of climatic conditions on the phenolic profile and thus suggest giving specific consideration to harvest time.  相似文献   

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