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1.
Experiments were conducted to study whether phaseolin type could influence proteolysis susceptibility and nutritional value of total bean protein. The DOR-390 bean cultivar was genetically modified to express different phaseolin types (S, T or I). Beans were soaked and autoclaved. A sequential hydrolysis was carried out in vitro with pepsin and pancreatin. Differences in the degree of protein hydrolysis among bean lines started at 30 min and remained until 240 min, with the S bean proteins presenting lower values (P < 0.05). Subsequently, rats were fed with diets containing beans expressing different phaseolin types as the only source of protein for N digestibility and nutritional value determination. No differences (P > 0.05) in ileal protein digestibility and rat growth were observed. In conclusion, the differences in in vitro hydrolysis between bean lines expressing different phaseolin types had no consequences on growth and N retention in rats.  相似文献   

2.
Buddleia officinalis Maxim, commonly used as rice dye for festivals, was extracted with ethanol using microwave-assisted extraction and Soxhlet extraction. The antioxidant activities of microwave-assisted extract of B. officialis (MEB) and Soxhlet extract of B. officianils (SEB) at the optimum extraction conditions were evaluated and compared with synthetic antioxidant butylated hydroxytoluene (BHT) employing DPPH free radical assay, ABTS assay, total antioxidant activity and reducing power. MEB and SEB had stronger antioxidant activities than BHT in all assays except reducing power, and the effects decreased as follows: MEB > SEB > BHT. The total phenolic contents of MEB and SEB reached 113.56 mg/g and 100.94 mg/g dry weight of extract, respectively, expressed as pyrocatechol equivalents, while the total flavonoids contents were 75.33 mg/g and 62.56 mg/g dry weight of extract, respectively, expressed as catechin equivalents (P < 0.05). Higher phenolic and flavonoids compounds may be major contributors to their higher antioxidant activities. Following activity-oriented separation, luteolin was isolated as an active principle, which exhibited excellent free radical scavenging activities with DPPH IC50 3.09 μg/ml and ABTS IC50 2.20 μg/ml.  相似文献   

3.
The effects of washing with hydrogen peroxide (H2O2) and sodium hypochlorite (NaOCl) solutions on the gel-forming ability and physicochemical properties of surimi produced from bigeye snapper (Priacanthus tayenus), stored in ice for up to 14 days, were investigated. Generally, pH and the trichloroacetic acid (TCA)-soluble peptide content of washed mince varied, depending on the type of oxidizing agent and storage time of the fish. With increasing time of storage, the pHs of water- and H2O2-washed mince were lower than that of NaOCl-washed mince (P < 0.05). However, no differences in the TCA-soluble peptide contents of the resulting mince washed with any media were observed (P > 0.05). Washing with 20 ppm NaOCl resulted in the highest increase in both the breaking force and the deformation of mince from fish stored in ice for all the times studied (P < 0.05). Natural actomyosin (NAM) extracted from NaOCl-washed mince had higher surface hydrophobicity and disulfide bond (SS) content than that of water-washed mince (P < 0.05). With no effect on Ca2+-, Mg2+-, or Mg2+–Ca2+-ATPase activities, NaOCl washing resulted in an increase in Mg2+–EGTA-ATPase activity of NAM (P < 0.05). The results suggested that washing mince with the appropriate type and concentration of oxidizing agent can improve the gelling ability of surimi, particularly from low quality fish.  相似文献   

4.
Our objective was to evaluate the influence of lactate on in vitro redox stability and thermostability of beef, horse, pork, and sheep myoglobins. Lactate (200 mM) had no effect (P > 0.05) on redox stability at physiological (pH 7.4, 37 °C) and meat (pH 5.6, 4 °C) conditions. However, lactate increased (P < 0.05) metmyoglobin formation at a condition simulating stressed live skeletal muscle (pH 6.5, 37 °C). The redox stability of myoglobins at stressed live skeletal muscle and meat conditions was species–specific (P < 0.05). Myoglobin thermostability at 71 °C was lower (P < 0.05) in the presence of lactate compared with controls and was influenced (P < 0.05) by species. The results of the present study indicate that the effects of lactate on myoglobin are temperature and pH dependent. The observed lack of influence of lactate on myoglobin redox stability at meat condition suggests that the color stability of lactate-enhanced fresh meat is not due to direct interactions between the ingredient and the heme protein.  相似文献   

5.
Epidemiological and experimental studies have suggested that high dietary fat intake of mice is associated with many physically degenerative diseases. Since oxidative stress and abnormal lipid metabolism have been speculated to be critical mechanisms underlying degenerative diseases, we hypothesized that a high-fat (HF) diet might induce oxidative stress or lipid oxidation and subsequently contribute to the high risk of some diseases such as cardiovascular and cerebrovascular ones. To test this hypothesis, male kunming mice were placed on either a HF diet or a normal laboratory diet for 30 consecutive days. This investigation demonstrated that blood fat [low density lipoprotein (LDL), total cholesterol (TC), triacylglycerols (TAG), high density lipoprotein (HDL)], blood sugar (blood glucose and liver glycogen) and oxidative stress (activities of antioxidant enzymes and levels of non-enzymic antioxidants) of mice fed high-fat diet (group II) were significantly increased or decreased (P < 0.05, P < 0.01) when compared with the control group (I). The present study revealed that HF diet induced oxidative stress and provided novel evidence regarding the link between high dietary fat and increased risk of degenerative diseases. The administration of Lycium barbarum polysaccharides did not show any effect on the body weight of the experimental mice, but significantly decreased the levels of LDL, TC, TAG, blood glucose and thiobarbituric acid reactive substances (TBARS) or increased the activities of antioxidant enzymes (P < 0.05, P < 0.01) when compared with mice in HF group (II). These findings were further supported by significantly increased non-enzymic antioxidants levels (P < 0.05, P < 0.01), suggesting that L. barbarum polysaccharides showed a noticeable inhibition against lipid oxidation induced by free radicals caused by HF diet intake (groups III, IV, V) on the basis of their antioxidant activities.  相似文献   

6.
The bio-nutritional potentials of three tropical vegetable leaf meals (Telfairia occidentalis leaf meal, TOLM; Talinum triangulare leaf meal, TTLM and Amaranthus cruentus leaf meal, ACLM) were investigated using albino rat as the test animal. Some protein quality evaluation indices were measured when the three vegetable leaf meals (VLMs) were used as sole protein sources in diets fed to the experimental animals and results were compared with data obtained for a basal nitrogen free diet (diet 1) and another reference diet (diet 2) in which the protein was solely supplied by nutritional casein (pure protein). The weight gain value recorded over a 10 day experimental period for the test animals on the reference (casein) diet 2 was consistently higher (P < 0.05) than the weight gain value obtained for the animals on the 3 VLMs diets (diets 3–5). Feed intake values recorded for the rats on the VLMs were similar (P > 0.05) and significantly higher (P < 0.05) than the value obtained for rats on the reference (casein) diet. Nitrogen excreted in faeces (feacal nitrogen) was lowest (P < 0.05) for the animals in reference diet 2. However, the nitrogen excreted in urine (urinary nitrogen) was highest (P < 0.05) for the animals on reference diet 2 and lowest for animals on diet 3 (TOLM diet) (P < 0.05). The nitrogen retention (NR) value obtained for the test animals on the reference diet 2 was similar (P > 0.05) to the value obtained for animals on diet 3 (TOLM). These values were significantly higher (P > 0.05) than NR values obtained for animals on diets 4 (TTLM) and 5 (ACLM). Expectedly, the apparent nitrogen digestibility (AND), protein efficiency ratio (PER), net protein ratio (NPR), true digestibility (TD), biological value (BV) and net protein utilization (NPU) all indicated higher and better values (P < 0.05) than the corresponding values obtained for the 3 VLMs diets (diets 3–5).  相似文献   

7.
The supercritical fluid extraction (SFE) trends and antioxidant activities of Hibiscus cannabinus seed oils were studied. SFE results indicate that extraction pressure is the major factor determining the oil yield. In comparison, classic Soxhlet extraction (SOX/L) yielded higher oil content than SFE (P < 0.05). However, no significant differences in oil content were observed in SFE at 600 bars/80 °C, rapid Soxhlet extraction (SOX/S) and conventional ultra-sonic assisted solvent extraction (SONIC) (P > 0.05). Antioxidant activities of H. cannabinus seed oils were compared with 7 types of commercial edible oils. DPPH scavenging activity test indicated that H. cannabinus seed oil extracted by SFE at 200 bars/80 °C possessed the highest antiradical activity whereas beta-carotene bleaching (BCB) assay revealed that all H. cannabinus seed oils (except for SFE at 400 bars/80 °C and 600 bars/80 °C) exhibited higher antioxidant activity than all commercial edible oils (P < 0.05). Thus, SFE – H. cannabinus seed oil may serve as an excellent source of solvent-free edible oil with high antioxidant properties.  相似文献   

8.
The effect of dietary protein and gastrointestinal nematode (GIN) parasitism on growth and meat quality of growing kids was assessed using sixty (60) kids in three groups (n = 20); A: control, B: regularly treated with ALBENDAZOLE® and C: supplemented with dietary protein. The kids grazed in a pasture contaminated with L3 larvae of GIN. Growth and condition score were assessed at 21-day intervals. After 86 days all kids were slaughtered. Carcasses were assessed for conformation, fatness, ultimate pH and other meat quality characteristics. Parasitic challenge was assessed by means of faecal egg counts (FEC), pasture larvae and adult nematodes in the GI tract of kids at slaughter. Groups C and B had higher growth rates and body condition score and produced significantly heavier (P < 0.05) carcasses with better (P < 0.01) conformation and fatness when compared to those of group A. Total unsaturated and monounsaturated fatty acids were higher (P < 0.05) in fat tissue of groups B and C. Group A had the highest FEC and group C had the lowest (P < 0.05) FEC. The parasitic challenge of L3 on pasture reached its highest point at 42 days and there were significant (P < 0.01) differences between the numbers of Teladorsagia spp., Trichostrongylus spp., Haemonchus contortus, Oesophagostomum spp. and Chabertia spp. found in the GI tract of kids between the three groups; group A had the highest numbers. Overall, the results showed that the increased protein content in the diet of growing kids grazing on a pasture contaminated with L3 nematode larvae resulted in the production of acceptable carcasses.  相似文献   

9.
The methanolic extract of Garciniamangostana fruit pericarp was partitioned into butanol and water fractions in this work. Three major phenolics were purified and identified as P1 [1,3,6,7-tetrahydroxy-2,8-(3-methyl-2-butenyl) xanthone], P2 [1,3,6-trihydroxy-7-methoxy-2,8-(3-methyl-2-butenyl) xanthone] and P3 (epicatechin). Strong antioxidant activities were detected for P1–P3. In vitro cell proliferation trials indicated that P1 and P3 exhibited good immunomodulatory activities when 7.5 μg/ml was used. Furthermore, P1 and P3 showed good cytotoxicities against human breast cancer cells (MCF-7) and human colon cancer cells (LOVO). P1 exhibited the maximal cytotoxicity of 73.06% against MCF-7 cells and of 46.27% against LOVO cells when 62.5 μg/ml was used. The cytotoxicities of P1, P2, P3 and paclitaxel against normal embryonic lung fibroblast cells (HELF) were in a decreasing order: paclitaxel > P3 > P1 > P2. These results suggested that P1 and P3 could be used as a potential anticancer agent.  相似文献   

10.
In the present investigation, a previously isolated Enterococcus faecium KH 24 strain was evaluated for the presence of virulence determinants (agg, esp, efaAfm, gelE, cylA, cylB, clyM, cpd, cob, ccf, ace and hyl), sensitivity to various antibiotics and production of biogenic amines. No virulence determinants were detected, except efaAfm. KH 24 was found to be sensitive to most of the tested antibiotics and none of the biogenic amines were produced by it. Moreover, KH 24 showed good in vitro tolerance to biological barriers and furthermore, its survival in gut of mice was also evaluated. Mice group fed with E. faecium KH 24 strain showed better weight gain and nearly 1 log cfu/g decrease in Salmonella enteritidis counts in the intestines as compared to control (p < 0.05). Enhanced growth of lactobacilli (p < 0.05) and decrease in coliform counts (p < 0.05) were also observed in test group. E. faecium KH 24 is, therefore, found to be a safe strain and it may be used as protective culture or as a probiotic in food preparations.  相似文献   

11.
The anti-inflammatory effects of the crude extract (CE) of Lotus corniculatus var. São Gabriel and its derived hexane (HEX), ethyl acetate (AcOEt), n-butanol (BuOH) and aqueous (Aq) fractions and isolated compounds kaempferitrin, oleanolic acid and β-sitosterol, in a mouse model of pleurisy induced by carrageenan were investigated. Swiss mice were used in the in vivo experiments. The crude extract of L. corniculatus and its derived fractions, and also its isolated compounds, inhibited leukocytes, exudation, and myeloperoxidase (MPO) and adenosine-deaminase (ADA) activities, as well as nitrite/nitrate concentration and interleukin-1 beta (IL-1β) level (< 0.05). L. corniculatus showed important anti-inflammatory activity by inhibition not only of leukocytes and/or exudation, but also of pro-inflammatory enzymes and mediators such as MPO, ADA, and IL-1β. The constituent’s kaempferitrin, oleanolic acid and β-sitosterol may well account for it.  相似文献   

12.
In vitro antioxidant activities of three selected Indian brown seaweeds – viz., Sargassum marginatum, Padina tetrastomatica and Turbinaria conoides – were investigated. Total phenolic content and reducing power of crude methanolic extract were also investigated. The activity of total methanolic extract and five different fractions (viz., petroleum ether (PE), ethyl acetate (EA), dichloromethane (DCM), butanol (BuOH) and aqueous) were studied using total antioxidant activity, DPPH radical scavenging and deoxyribose assays. EA fraction of S. marginatum exhibited higher total antioxidant activity of 39.62 mg ascorbic acid equivalent/g extract (or 0.31 mg ascorbic acid equivalent/g seaweed on dry weight basis) among the all the fractions. Among the fractions obtained from different seaweeds, EA fraction of S. marginatum showed higher DPPH scavenging activity of 23.16%; while PE fraction of T. conoides exhibited lower deoxyribose activity of 47.81%. Higher phenolic content (49.16 mg gallic acid equivalent/g extract or 0.86 mg GAE/g of seaweed on dry weight basis) was noticed in aqueous fraction of T. conoides. Reducing power of crude methanolic extract increased with increasing concentration. Reducing power of T. conoides and P. tetrastomatica were higher compared to standard antioxidant (α-tocopherol). Among the seaweeds, total methanolic extract of T. conoides had significantly higher phenol content (P < 0.05) compared to the other two species. In vitro antioxidant activity of methanolic extracts from all the three seaweeds showed an increase with increasing concentration indicating the dose dependency of these properties.  相似文献   

13.
Methanolic extracts of low-grade green coffee beans (LCB) and spent coffee were analysed for radical-scavenging activity (α,α-diphenyl-β-picrylhydrazyl radical) and oxygen radical absorbance capacity (ORAC). The extracts were also evaluated for anti-tumour (P388 cell assay), anti-inflammatory (J774A.1 cell assay) and anti-allergenic (RBL-2H3 cell line) activities in vitro. LCB extract was found to exhibit a radical-scavenging activity of 92.0% followed by spent Arabica (86.9%) and spent Robusta (82.0%) at a concentration of 50 ppm. The antioxidant activity of LCB extract, measured as Trolox equivalents (4416 μM/g) was significantly (p < 0.05) higher than that of the spent coffee extracts. However, extracts of spent coffee exhibited significantly (p < 0.05) more anti-tumour activity than the LCB extract in terms of cell viability. This could be due to the possible role of brown pigments (melanoidins and phenolic polymers), formed during roasting, which may protect cells from oxidative damage in the biological system. However, both the extracts of LCB and spent coffee showed limited anti-inflammatory and anti-allergic activities. The presence of phenolics and chlorogenic acids in appreciable quantities along with brown pigments makes these coffee by-products a source for natural antioxidants.  相似文献   

14.
The in vitro antioxidant activity and in vivo anti-fatigue activity of loach peptide (LP) were determined. Results showed that LP contained the amino acids, which were expected to contribute to its antioxidant and anti-fatigue activities. LP could scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) (IC50 17.0 ± 0.54 mg/ml) and hydroxyl radicals (IC50 2.64 ± 0.29 mg/ml). It could chelate cupric ion and inhibit the lipid peroxidation in a linoleic acid emulsion system. It also prolonged the swimming time to exhaustion of mice by 20–28% compared to the control. It increased the levels of blood glucose (28–42% increase) and liver glycogen (2.3–3.0-fold increase). It decreased the levels of lactic acid and blood urea nitrogen by 10.9–27.5% and 8.6–17.5%, respectively. It also improved the endogenous cellular antioxidant enzymes in mice by increasing the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px). Therefore, LP can increase an endurance capacity and facilitate recovery from fatigue.  相似文献   

15.
The in vitro and in vivo protective effects of water extract of pu-erh tea (WEPT) on tert-butyl-hydroperoxide (t-BHP)-induced oxidative damage in hepatocytes of HepG2 cells and in rat livers were investigated. After treatment with 200 μg/ml of samples, the survival rate of HepG2 cells induced by t-BHP increased. WEPT concentration-dependently inhibited reactive oxygen species (ROS) generation in HepG2 cells in response to the oxidative challenge induced by t-BHP. Administration of WEPT (0.2, 0.5 and 1.0 g/kg of body weigh) to rats for 56 consecutive days before a single dose of t-BHP (0.5 mmol/kg, i.p.) exhibited a significant (p < 0.01) protective effect by lowering serum levels of glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT), as well as reducing the formation of malondialdehyde. Taken together, these results demonstrate that WEPT is able to protect against hepatic damage in vitro and in vivo, suggesting that the drinking of pu-erh tea may protect liver tissue from oxidative damage.  相似文献   

16.
This study examined the lactate-mediated enzymatic reduction of equine metmyoglobin (MMb) by using various lactate salts (sodium, potassium and calcium) and bovine m. triceps brachi extracts in vitro. The equine MMb was reduced by the assay mixture containing lactate, NAD+, and the muscle extract at pH 5.7. In the absence of the bovine muscle extract, NAD+ or l-lactate in the assay mixture, MMb reduction was not observed. Replacing l-lactate with d-lactate or adding oxalate (lactate dehydrogenase inhibitor) to the assay mixture resulted in no MMb reduction, suggesting that lactate dehydrogenase is involved in the MMb reduction, interacting with l-lactate and NAD+. An increase (P < 0.05) in the rate of MMb reduction was also observed with an increase of the amount of bovine muscle extract, NAD+ or lactate concentration in the assay mixture. There was no difference (P > 0.05) in the rate of MMb reduction when potassium lactate was added to the assay mixture instead of sodium lactate. The MMb reduction through the lactate–NAD+-muscle extract system was increased (P < 0.05) with an elevation in pH from 5.1 to 6.1. The results of this research confirm that the inclusion of l-lactate can induce the MMb reduction through the lactate– NAD+-enzyme coupling interaction.  相似文献   

17.
Resistant starch (RS) content was determined in 10 indica and japonica milled rices with different levels of amylose. The effect of microbial growth during starch digestion on the measurement of RS, and the correlation between physico-chemical characteristics and RS contents of milled rice were analysed. Results indicated a significant decrease (P < 0.01) in assay values of RS after antibiotics addition, and the markedly decreased sample pH due to fermentation might be the main reason for errors in RS determination. Correlation analyses showed that RS contents of milled rice were closely related to amylose content (r = 0.75, P < 0.05) and protein content (r = 0.78, P < 0.01). No significant correlation existed between RS content and some relatively simple physical properties, such as width, shape and elongation ratio of rice grain, which were reported to be good indictors of rate of rice starch digestion, while a significant positive correlation was found between elongation ratio and digestible starch in cooked milled rice (r = 0.67, P < 0.05).  相似文献   

18.
The effects of selenium-containing green tea (SGT; 1.4 mg selenium/kg) and China green tea (CGT; 0.13 mg selenium/kg) on the in vitro growth of lactobacilli and bifidobacteria were investigated using pure and mixed cultures. SGT had significantly higher phenolic contents (TPC), higher reducing activity, higher DPPH free-radical scavenging activity, and higher ferrous-ion chelating activity (P < 0.05–0.0001) than CGT. The addition of aqueous extracts from CGT to Mann-Rogosa-Sharpe (MRS) broth at 10% and 25% (v/v) resulted in small but nonsignificant (P > 0.05) increases in the numbers of Lactobacillus rhamnosus and Bifidobacterium breve over the control incubations (without tea). Addition of 10% and 25% of SGT extract resulted in a significant increase (P < 0.05–0.0001) in the number of lactobacilli and bifidobacteria recovered from batch fermentation while CGT did not increase the number of bifidobacteria. The higher prebiotic activity of SGT over CGT may be related to the higher TPC or minerals, notably selenium or a combination of these factors. To test whether selenium itself has an effect on bacterial growth, Na-selenite and Na-selenate were added alone or in combination with CGT to the MRS broth containing pure culture of L. rhamnosus. Growth of this bacterium was enhanced relative to the control incubation of MRS only. When added in combination with CGT, Na-selenate was more effective at enhancing the growth of L. rhamnosus than Na-selenite. The prebiotic effect of SGT could be largely explained by its selenium content.  相似文献   

19.
Antioxidant and antibacterial activities of freeze-dried and irradiated parsley (Petroselinum crispum) and cilantro (Coriandrum sativum) leaves and stems were determined on methanol and water extracts. The total phenolic content was quantified with the Folin–Ciocalteau reagent. Several mechanisms of potential antioxidant activity of all extracts, including determining relative free radical-scavenging and ferrous ion-chelating activities, as well as reducing power, were examined. Assessment of the total antioxidant activity of all extracts was done using an iron-induced linoleic acid oxidation model system. Antimicrobial activity towards Bacillus subtilis and Escherichia coli by different extracts was assessed by determining cell damage. Total phenolic content varied between parsley and cilantro, leaf and stem, as well as methanol and water extracts. Methanol-derived leaf extracts exhibited significantly (p < 0.05) greater radical-scavenging activity towards both lipid- and water-soluble radicals, which was attributed to the total phenolic content. Ferrous ion-chelating activity was significantly (p < 0.05) greater in the stem methanol extracts, and corresponded to antioxidant activity. Prooxidant activity was a feature of all aqueous extracts and corresponded to the reducing activity of both leaf and stem parts of parsley and cilantro. Bacterial cell damage, resulting in significant (p < 0.05) greater growth inhibition of B. subtilis and E. coli, corresponded to ferrous sequestering activity of methanol-derived stem extracts.  相似文献   

20.
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   

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