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1.
Syzygium aqueum is a medicinal plant which is grown in tropical regions. In this study, the ethanolic extracts of S. aqueum leaf were investigated for its antihyperglycaemic activity. Our investigation revealed its effectiveness in inhibiting the carbohydrate hydrolysing enzymes, α-glucosidase (EC50 = 11 μg/ml) and α-amylase (EC50 = 8 μg/ml), at significant level than the commercial drug acarbose (EC50 = 28 μg/ml, α-glucosidase; EC50 = 12 μg/ml, α-amylase). In addition, the ethanolic leaf extracts were able to inhibit the key enzyme in the polyol pathway, aldose reductase (EC50 = 0.03 μg/ml) and prevent the AGEs formation by 89%. Six flavonoid compounds, 4-hydroxybenzaldehyde (1), myricetin-3-O-rhamnoside (2), europetin-3-O-rhamnoside (3), phloretin (4), myrigalone-G (5) and myrigalone-B (6), were isolated from the ethanolic leaf extracts. Compounds (2) and (3) showed high inhibitory activities, with EC50 values of 1.1 μM and 1.9 μM against α-glucosidase and EC50 values of 1.9 μM and 2.3 μM against α-amylase, respectively. These findings provide a strong rationale to establish S. aqueum’s capability as an antihyperglycaemic agent.  相似文献   

2.
This study investigated the impact of two information conditions and two androstenone concentrations on the acceptability of fermented sausages made from boar meat. Two batches of salamis were produced by mixing bellies and lean meat resulting in average androstenone levels of 0.408 μg/g vs. 1.585 μg/g melted fat, respectively. Skatole levels were kept below 0.05 μg/g melted fat in the final products. The consumers were provided with either the information that the products consisted of 100% pork or 100% boar meat. In total, 478 visitors of an animal husbandry fair, assumed to be familiar with the consequences of not castrating male piglets, evaluated the salami following a monadic between-subject design. The information did not significantly affect the hedonic scores. The percentage of dislikes was very low, i.e. 3 vs. 6% (p = 0.24) for salami LOW and HIGH, respectively. The batch with lower androstenone content was liked slightly but significantly better (p = 0.03).  相似文献   

3.
The objectives of this study were to examine the antioxidant activities and free radical scavenging effects of extracts of aqueous leaves of Psidium guajava L. (PE), Camellia sinensis (GABA tea; CE), Toona sinensis Roem. (TE) and Rosemarinus officinalis L. (RE). Among the four extracts, PE exhibited the strongest efficiency and showed over 50% scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals at the concentration of 100 μg/mL. The reducing power of four nutraceutical herbs was in the order of PE > RE > CE > TE. The antioxidant activities of nutraceutical herbs were evaluated in a liposomes oxidation system promoted by Fe3+/ascorbic acid/H2O2. PE still showed the strongest antioxidant activity and exhibited over 95% inhibition at concentration of 50 μg/mL. The antioxidant activity of TE was still lower than that of other herbal plants; however, it also displayed 89% inhibition at concentration of 250 μg/mL. RE exhibited well inhibitory effects on the UVB-induced oxidation of erythrocyte ghosts at lower concentration (100 μg/mL). However, the protection of PE on the UVB-induced oxidation was significantly raised with increasing the concentrations and reached 95.4% inhibitory effects at concentration of 500 μg/mL. These results show that the tested herbal tea, especially PE could be considered as a natural antioxidant source.  相似文献   

4.
The essential oil obtained from aerial parts of Satureja montana L. and Origanum vulgare L. (Labiatae) along with four of its main components, p-cymene, carvacrol, thymol and γ-terpinene were tested in models of in vitro peroxynitrite-induced formation of both 3-nitrotyrosine and malondialdehyde, two biomarkers of the oxidative stress of recognised pathological and toxicological significance. The essential oils showed a significant activity, thus decreasing 3-nitrotyrosine formation (IC50 values of 43.9 μg/ml for S. montana and 19.2 μg/ml for O. vulgare), and also inhibited the peroxynitrite induced malondialdehyde formation (IC50 values of 27.2 μg/ml and 17.0 μg/ml respectively). Thymol and carvacrol inhibited 3-nitrotyrosine formation (IC50 values of 81.3 μM and 106.3 μM; ascorbic acid IC50 = 400 μM) and reduced malondialdehyde formation (IC50 values of 43.9 μM and 70.1 μM respectively; trolox IC50 = 240 μM). On the contrary, p-cymene and γ-terpinene were completely inactive in both assays under the concentration of 300 μg/ml. These results support, in particular for origanum, the nutraceutical value of these spices and the potential of thymol and carvacrol in preventing the formation of toxic products by the action of reactive nitrogen species.  相似文献   

5.
The objective of this study was to establish an analytical method to measure pesticides used to cultivate yuza (Citrus junos Sieb. ex Tanaka) and to analyze pesticide residue levels of yuza and yuza tea samples. Risk assessments were also performed by calculating estimated daily intake (EDI) and acceptable daily intake (ADI). An excellent linear correlation was achieved with coefficient correlation values of 0.9750–0.9999. Percent recoveries were 80.4–109.9% for most pesticides with a <6.9% relative standard deviation (RSD). The limits of quantification for the method were 0.10–0.67 μg/ml. The RSD of intra-day and inter-day variability was <15.3%. Seven pesticides in yuza (n = 80) and yuza tea (n = 75) were analyzed with the optimized analytical method. Acequinocyl, spirodiclofen and carbendazim were detected in yuza samples in the concentration range of 0.07–0.15 μg/g, 0.11–1.89 μg/g, and 0.03–5.15 μg /g, respectively, whereas chlorpyrifos, prothiofos, phosalone, and deltamethrin were not detected in yuza or yuza tea. The concentrations of acequinocyl, spirodiclofen and carbendazim ranged from 0.18–1.05 μg/g, 0.13–0.29 μg/g, and 0.17–2.36 μg/g, respectively, in yuza tea samples. The percent ratios of EDI to ADI for acequinocyl, spirodiclofen, and carbendazim were 24.6%, 22.7%, and 58.5%, respectively.  相似文献   

6.
The objectives of the current study were to evaluate the efficacy and field safety of GnRH HCl administered at 3 doses in fixed-time artificial insemination (FTAI) programs (Ovsynch) in dairy cows. A common protocol was conducted at 6 commercial dairies. Between 188 and 195 cows were enrolled at each site (total enrolled = 1,142). Cows had body condition scores ≥2 and ≤4, were between 32 to 140 d in milk, and were clinically healthy. Within pen and enrollment day (enrollment cohort), cows were assigned randomly in blocks of 4 to each of 4 treatments: (1) 25 mg of PGF on d 7 with FTAI 72 ± 2 h later (control); (2) 100 μg of GnRH on d 0, d 7 a dose of 25 mg of PGF, and the second administration of 100 μg of GnRH (T100) administered either at 48 ± 2 h (d 9) after PGF with FTAI 24 ± 2 h later or 56 ± 2 h (d 9) after PGF and FTAI 17 ± 2 h later; (3) same as T100 with both injections of 150 μg of GnRH (T150); and (4) same as T100 with both injections of 200 μg of GnRH (T200). Three sites selected the first option and 3 sites selected the second option for the timing of the second injection of all doses of GnRH. Cows were observed daily for signs of estrus and adverse clinical signs. Cows not returning to estrus had pregnancy diagnosis between 42 and 65 d following FTAI. Pregnancies per FTAI (P/FTAI) were analyzed as a binary variable (1 = pregnant, 0 = not pregnant) using a generalized linear mixed model with a binomial error distribution and a logit link function. The statistical model included fixed effects for treatment, random effects of site, site by treatment, enrollment cohort within site, and residual. Parity (first vs. second or greater) was included as a covariate. For demonstration of effectiveness, α = 0.05 and a 2-tailed test were used. Fifty-two cows were removed from the study because of either deviation from the protocol, injury, illness, culling, or death. Among the remaining 1,090 cows, 33.9% were primiparous and 66.1% were multiparous. Back-transformed least squares means for P/FTAI were 17.1, 27.3, 29.1, and 32.2% for control, T100, T150 and T200, respectively. The P/FTAI for each GnRH dose differed from that of the control. No differences were detected in P/FTAI between GnRH doses. No treatment-related adverse events were observed. Mastitis was the most frequently observed adverse clinical sign, followed by lameness and pneumonia. This study documents the efficacy and safety of doses of 100 to 200 μg of GnRH as the HCl salt when used in Ovsynch programs.  相似文献   

7.
Anthocyanin pigments in coloured rice cultivars were isolated and identified using high-performance liquid chromatography techniques. Two black rice cultivars (Asamurasaki, Okunomurasaki) contained three major anthocyanins: cyanidin-3-glucoside, peonidin-3-glucoside and malvidin. Chinakuromai (black) rice additionally contained a fourth anthocyanin, petunidin-3-glucoside. Four red rice cultivars contained only malvidin. The total anthocyanin content varied greatly among black rice cultivars (79.5–473.7 mg/100 g), but was lower in red rice (7.9–34.4 mg/100 g). Total phenolic content was similar between red (460.32–725.69 mg/100 g) and black (417.11–687.24 mg/100 g) rice. The oxygen radical absorbing capacity was ranked as follows: red (69.91–130.32 μmol Trolox/g) > black (55.49–64.85 μmol Trolox/g) > green (35.32 μmol Trolox/g) > white (21.81 μmol Trolox/g) rice. The antioxidant capacity resulted mainly from the seed capsule, not the endosperm. The anthocyanin pigments contributed little to the total antioxidant capacity of red (0.03–0.1%) and black (0.5–2.5%) rice cultivars. Hence, the antioxidant capacity is derived mainly from other phenolic compounds.  相似文献   

8.
Immunoglobulin in yolk (IgY) (with a titer of 1.3 × 106) specific against bovine milk (BM) alkaline phosphatase (ALP) was obtained by intramuscularly immunizing hens on the thigh and was used as the primary antibody to conduct competitive indirect enzyme-linked immunosorbent assay (CI-ELISA) to determine BMALP in ALPs from BM and Escherichia coli sources. A relationship between the ELISA value and the BMALP level (0.01–10 μg/mL) in whole milk (R2 = 0.9019) or in skimmed milk (R2 = 0.9402) was observed. The maximal inhibition (%) of BMALP on the microtiter plate by free BMALP at 10 μg/mL whole milk (3.89 mU/μg BMALP) was about 50%, while no inhibition (%) of BMALP by free E. coli ALP at concentrations between 0.01 to 10 μg/mL (60 mU/μg E. coli ALP) was determined. At BMALP levels higher than 0.1 μg/mL, CI-ELISA was proved to be effective in differentiating between BMALP and E. coli ALP and quantifying BMALP in whole milk or skimmed milk in the presence of E. coli ALP with an activity of 0.6 U/mL. Higher inhibition (about 70%) of BMALP on the microtiter plate by free BMALP in diluted (101–104 fold) milk samples was observed. The optimal conditions for CI-ELISA in determining BMALP (0.1–10 μg/mL) from ALPs in milk samples were using 103-fold diluted crude IgY specific against BMALP as primary antibody and 103-fold diluted goat anti-chicken IgG–ALP conjugate as the secondary antibody.  相似文献   

9.
The present study investigates the antimicrobial activity of various solvent extracts of Eruca sativa (aerial and root) and seed oil against-antibiotic resistant Gram-negative (Escherichia coli, Pseudomoms aeruginosa and Shigella flexneri) and Gram-positive (Staphylococcus aureus and Bacillus subtilis) bacteria. Among the various preparations, seed oil was the most active, exhibiting a maximum zone inhibition of 97% for Gram-positive bacteria and of 74–97% for Gram-negative bacteria. The MIC of the seed oil was found to be 65–75 and 60–70 μg/ml for Gram-negative and Gram-positive bacteria, respectively. Analytical investigation on main volatile and non-volatile components was performed on seed oil. Among the formers allyl isothiocyanate (40 μg/g), 3-butenyl isothiocyanate (260 μg/g), 4-methylsulfinybutyl isothiocyanate (sulforaphane 743 μg/g), 2-phenylethyl isothiocyanate (159 μg/g) and bis(isothiocyanatobutyl)disulphide (∼5000 μg/g) were determined by head space/SPME/GC–MS analysis. Free fatty acids were 1.6% w/w of the oil and overall 25 fatty acids were identified. Erucic and oleic acids were the main fatty acids both in the free (7.8 and 2.1 mg/ml) and esterified forms (50.6% w/w and 14.9% w/w of total fatty acids). Unsaponifiable fraction was 1.8% w/w.  相似文献   

10.
Headspace solid-phase microextraction (HS-SPME) gas chromatography was used to analyze target flavor compounds in orange beverage emulsion. The effects of SPME fiber (PDMS 100 μm, CAR/PDMS 75 μm, PDMS/DVB 65 μm and DVB/CAR/PDMS 50/30 μm), adsorption temperature (25–45 °C), adsorption time (5–25 min), sample concentration (1–100%), sample amount (5–12.5 g), pH (2.5–9.5), salt type (K2CO3, Na2CO3, NaCl and Na2SO4), salt amounts (0–30%) and stirring mode were studied to develop HS-SPME condition for obtaining the highest extraction efficiency and aroma recovery. For the head space volatile extraction, the optimum conditions were: CAR/PDMS fiber, adsorption at 45 °C for 15 min, 5 g of diluted beverage emulsion (1:100), 15% (w/w) of NaCl with stirring and original pH 4. The main volatile flavor compounds were: limonene, 94.9%; myrcene, 1.2%; ethyl butyrate, 1.1%; γ-terpinene, 0.41%; linalool, 0.36%; 3-carene, 0.16%; decanal, 0.12%; ethyl acetate, 0.1%; 1-octanol, 0.06%; geranial, 0.05%; β-pinene, 0.04%; octanal, 0.03%; α-pinene, 0.03%; and neral, 0.03%. The linearity was very good in the considered concentration ranges (R2 ? 0.97). Average recoveries ranged from 88.3% to 121.7% and showed good accuracy for the proposed analytical method. Average relative standard deviation (RSD) for five replicate analyses was found to be less than 14%. The limit of detection (LOD) ranged from 0.06 to 2.27 mg/l for all volatile flavor compounds and confirmed the feasibility of the HS-SPME technique for headspace analysis of orange beverage emulsion. The method was successfully applied for headspace analysis of five commercial orange beverage emulsions.  相似文献   

11.
The essential oil from underground parts of Ferula heuffelii from N.E. Serbia, was analysed using GC and GC–MS. The main compounds of the essential oil were elemicin (35.4%) and myristicin (20.6%). The essential oil exhibited the best antimicrobial activity against two strains of Candida albicans (MIC = 7.0 and 13.7 μg/ml), as well as against Micrococcus luteus (MIC = 13.7 μg/ml), Staphylococcus epidermidis (MIC = 17.6 μg/ml), Bacillus subtilis (MIC = 21.1 μg/ml) and Micrococcus flavus (MIC = 28.2 μg/ml). In the DPPH radical scavenging assay, essential oil showed substantial activity with SC50 = 22.43 μl/ml. The essential oil was also tested for antispasmodic activity. It inhibited spontaneous contraction of isolated rat ileum dose-dependently, and at the concentration of 86.64 μg/ml exhibited 50% of the maximum effect of atropine. After incubation with 75.00 μg/ml of essential oil, acetylcholine did not induce contractions of ileum, and at 250.00 μg/ml, the essential oil almost completely abolished the spasmodic effect of potassium chloride (80 mM).  相似文献   

12.
Migration levels of commercial plasticisers [di-(2-ethylhexyl) adipate (DEHA) and acetyl tributyl citrate (ATBC)] from polyvinyl chloride (PVC) film into the EU specified aqueous food simulants (distilled water, 3% w/v acetic acid and 10% v/v ethanol) were monitored as a function of time. Migration testing was carried out at 40 °C for 10 days (EEC, 1993). Determination of the analytes was performed by applying the analytical methodology based on surfactant (Triton X-114) mediated extraction prior to gas chromatographic-flame ionisation detection (GC-FID) recently proposed by our group. The study focuses on the determination of the effect of gamma radiation on plasticiser migration into the selected simulants. PVC cling film used was subjected to ionising treatment with a [60Co] source at doses equal to 5, 15 and 25 kGy. DEHA and ATBC migration into the EU aqueous simulating solvents was limited, yielding final concentrations in the respective ranges 10–100 μg/l and 171–422 μg/l; hence, ATBC demonstrated a stronger interaction with all three simulants compared to DEHA. Migration data, with respect to ATBC, showed that the most aggressive simulant seemed to be the 10% ethanol, while in the case of DEHA the 3% aqueous acetic acid exhibited the highest extraction efficiency; distilled water demonstrated the lowest migration in both cases. With regard to PVC treatment with gamma rays, high radiation doses up to 25 kGy produced a statistically significant (< 0.05) effect on the migration of both plasticisers.  相似文献   

13.
Ten hydroalcoholic extracts of edible plants from the Calabria region (Italy) were evaluated for their in vitro antioxidant and antiradical properties and in vivo topical anti-inflammatory activity. All the extracts had radical-scavenging and/or antioxidant properties, the most active plants being hawkweed oxtongue and viper’s bugloss. The best free radical (DPPH·)-scavenging activity was found in hawkweed oxtongue and chicory leaves extracts (IC50 = 25 and 26 μg/ml, respectively). Hawkweed oxtongue, poppy and viper’s bugloss extracts showed the greatest inhibition of linoleic acid oxidation (IC50 = 3 μg/ml). Viper’s bugloss and hawkweed oxtongue extracts had the greatest antioxidant effect on bovine brain peroxidation (IC50 = 11 and 22 μg/ml). All the extracts also showed an anti-inflammatory effect: 300 μg/cm2 provoked oedema reductions ranging from 18% to 43%. Cress was the most active plant. Chicory leaves contained the highest amount of phenolics (190 mg/g) whilst Rush crimps contained the highest amount of flavonoids (32.9 mg/g), followed by hawkweed oxtongue (15.8 mg/g). Cress contained the highest number of sterols. Among them, γ-sitosterol (12.2%) and ergost-5-en-3-ol (3β) (4.5%) were found to be the major constituents. Moreover, three of the identified molecules (stigmasta-5,23-dien-3β-ol, stigmasta-5,24(28)-dien-3-ol (3β,22E) and 9,19-cyclolanost-24-en-3-ol (3β)) were found in this plant only.  相似文献   

14.
Epidemiological evidence has linked consumption of sorghum with reduced incidences of gastrointestinal cancer, especially cancer of esophagus. No information is available on how sorghum may effect the chemoprotective properties. We investigated in vitro potential of eight sorghum varieties to induce phase II detoxifying enzymes using the NAD(P)H:quinone oxidoreductase (NQO) enzyme assay, and also inhibit proliferation of esophageal, OE33, and colon, HT-29, carcinoma cells using the PicoGreen and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays; these properties were compared to phenolic profile and antioxidant activity of the sorghum. Black sorghum extract high in 3-deoxyanthocyanins was the most potent NQO inducer, doubling NQO activity at 5.0 μg/mL and maximally inducing the enzyme activity by 3.0 times. White sorghum was a moderately strong inducer, maximally increasing NQO activity by 80%; tannin-containing sorghums were non-inducers. On the other hand, the tannin-containing sorghum extracts had strongest antiproliferative activity against both OE33 and HT-29 cells (IC50, 38-105 μg/mL); the white sorghum extract was the least potent (IC50, 389->800 μg/mL). Antiproliferative activity correlated with antioxidant activity whereas NQO-inducer capacity did not. Sorghum extracts have strong chemoprotective potential which is partially independent of their antioxidant properties. They may thus be valuable health-promoting ingredients in whole-grain based products.  相似文献   

15.
The antiproliferative effect of an immature Citrus grandis Osbeck fruit extract was investigated using U937 human leukaemia cells. Maximum cytotoxicity was observed using the hexane fraction (HF) of the extract. Cell death was dose-dependent (IC50 = ca. 60 μg/ml) and was characterised by chromatin condensation, apoptotic body formation, and DNA fragmentation. The induction of apoptosis was confirmed by caspase-3 activity assays and by immunoblotting using antibodies against Bcl-2, Bax, poly(ADP-ribose) polymerase (PARP), caspase-9, and caspase-3. The molecular mechanism underlying HF-induced apoptosis in U937 cells may involve a mitochondria-mediated signalling pathway, as demonstrated by an increase in the Bax/Bcl-2 expression ratio. Analyses of the HF by gas chromatography (GC) and GC-mass spectrometry (MS) tentatively identified 19 compounds, including γ-sitosterol (17.5%), 7-methoxy-8-(2-oxo-3-methylbutyl) coumarin (6.8%), stigmasterol (3.8%), and campesterol (3.4%). Together, our results provide the first evidence that the HF of an immature C. grandis Osbeck fruit extract induces apoptosis in U937 cells.  相似文献   

16.
Essential oil from the aerial parts of Artemisia indica was analysed by GC-FID and GC–MS. A total of 43 compounds representing 96.8% of the oil were identified and the major components were found to be artemisia ketone (42.1%), germacrene B (8.6%), borneol (6.1%) and cis-chrysanthenyl acetate (4.8%). Antimicrobial activity of the oil was evaluated against seven clinically significant bacterial and two fungal strains. The essential oil and its major constituents exhibited moderate to potent, broad-spectrum antibacterial and antifungal activities targeting both Gram-positive and Gram-negative bacteria. In vitro cytotoxicity evaluation against four human cancer cell lines THP-1 (leukemia), A-549 (lung), HEP-2 (liver) and Caco-2 (colon) showed that the essential oil exhibited concentration dependant growth inhibition in the 10–100 μg/ml dilution range, with IC50 values of 10 μg/ml (THP-1), 25 μg/ml (A-549), 15.5 μg/ml (HEP-2) and 19.5 μg/ml (Caco-2). It was interesting to note that the essential oil also exhibited potent antioxidant activity.  相似文献   

17.
The residue dynamics of plant growth regulators (PGR) forchlorfenuron (CPPU), 6-benzylaminopurine (6-BA), gibberellic acid (GA3) and ethephon in grape are presented, corresponding to their field applications at recommended and double doses. Random samples were collected from each treated and control plot at regular time intervals. The optimised sample preparation technique involves extraction of 10 g homogenised sample with 20 ml methanol (+1% formic acid) and measurement by LC–MS/MS multiple reaction monitoring, offering limit of quantification ?0.0025 μg/g for all except ethephon with LOQ of 0.005 μg/g. The recoveries at LOQ and above were 84.8–109.5%. Residue dissipation of all the PGRs followed non-linear two-compartment first + first-order kinetics. CPPU, 6-BA and ethephon residues dissipated with preharvest intervals (PHIs) of 33.5, 12 and 32 days at recommended dose with no PHI applicable for GA3. The PHIs successfully minimised residue problems as observed from survey results of traceable field samples.  相似文献   

18.
Total phenolic content, proanthocyanidins, gallotannins, flavonoids, and antioxidant activities of Sclerocarya birrea and Harpephyllum caffrum methanolic extracts were evaluated using in vitro assays. S. birrea young stem extract contained the highest levels of total phenolic content (14.15 ± 0.03 mg GAE/g), flavonoids (1.21 ± 0.01 mg CE/g) and gallotannins (0.24 ± 0.00 mg GAE/g). H. caffrum stem bark extract had the highest content of proanthocyanidins (1.47%). The EC50 values of the extracts in the DPPH free radical scavenging assay ranged from 4.26 to 6.92 μg/ml, compared to 6.86 μg/ml for ascorbic acid. A dose-dependent linear curve was obtained for all extracts in the ferric-reducing power assay. Dichloromethane and methanol extracts exhibited dose-dependent acetylcholinesterase inhibitory activity. Similarly, all extracts exhibited high antioxidant activity comparable to butylated hydroxytoluene based on the rate of β-carotene bleaching (84.1–93.9%). The two Anacardiaceae species provide a source of natural antioxidants and acetylcholinesterase inhibitors, and may be beneficial to the health of consumers.  相似文献   

19.
Shahid Iqbal  M.I. Bhanger 《LWT》2007,40(2):361-367
Antioxidant activity of bran extracts from five wheat varieties indigenous to Pakistan, i.e. Punjab-96, Bhakkar-2002, Uqab-2000, SH-2002, and Pasban-90, has been evaluated. All the bran extracts exhibited appreciable total phenolic content (2.12-3.37 mg gallic acid equivalent/g bran), total flavonoid content (epicatechin equivalent 262-304 μg/g bran), chelating activity (ethylenediaminetetracetate equivalent 597-716 μg/g bran), 2,2′-diphenyl-1-picrylhydrazyl radical scavenging activity (51-79%), ABTS radical cation scavenging activity (Trolox equivalent 27-36 μmol/g), oxygen radical absorbance capacity (97-123 μmol/g), and total anthocyanin content (30-38 mg/kg bran). Tocopherol (22-26 ppm) and tocotrienol content (59-74 ppm) were determined by RP-HPLC. For confirmation of tocopherol content, polarographic study was conducted, which further authenticated the results (21-25 ppm). All the varieties exhibited appreciable antioxidant potential and significant differences were observed among the varieties in different systems of antioxidant activity evaluation.  相似文献   

20.
Saponins are naturally occurring metabolites associated with several health benefits. The objective was to quantify and purify saponins from mate dry leaves, and to assess their anti inflammatory and apoptotic mechanisms in human colon cancer cells in vitro. Matesaponins were extracted with methanol from dry leaves, partially purified and quantified. Leaves contained 10–15 mg/g dry weight total saponins, predominantly matesaponins 1 and 2. HPLC and LC/ESI-MS-MS identified saponins in six preparative chromatographic fractions (A, B, C, D, E, and F). Major matesaponins were identified as 1 [M–H] = 911 and 2 [M–H] = 1057, with trace amounts of 3 [M–H] = 1073, 4 [M–H] = 1219, and 5 [M–H] = 1383. Fractions D, E, and F significantly inhibited iNOS (IC35 = 36.3, 29.5, 43.7 μM), PGE2 (IC35 = 23.1, 22.3, 11.7 μM) and COX-2 (IC35 = 45.7, 32.4, 17.0 μM). Fraction F reduced nuclear translocation of nuclear factor-κB subunits p50 (49.8%) and p65 (49.0%) and induced apoptosis through suppression of Bcl-2 and increased Bax protein expressions and activated caspase-3 activity. Saponins in leaves of mate prevent inflammation and colon cancer in vitro.  相似文献   

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