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1.
Spices and vegetables possess antioxidant activity that can be applied for preservation of lipids and reduce lipid peroxidation in biological systems. The potential antioxidant activities of selected spices extracts (water and alcohol 1:1) were investigated on enzymatic lipid peroxidation. Water and alcoholic extract (1:1) of commonly used spices (garlic, ginger, onion, mint, cloves, cinnamon and pepper) dose-dependently inhibited oxidation of fatty acid, linoleic acid in presence of soybean lipoxygenase. Among the spices tested, cloves exhibited highest while onion showed least antioxidant activity. The relative antioxidant activities decreased in the order of cloves, cinnamon, pepper, ginger, garlic, mint and onion. Spice mix namely ginger, onion and garlic; onion and ginger; ginger and garlic showed cumulative inhibition of lipid peroxidation thus exhibiting their synergistic antioxidant activity. The antioxidant activity of spice extracts were retained even after boiling for 30 min at 100 degrees C, indicating that the spice constituents were resistant to thermal denaturation. The antioxidant activity of these dietary spices suggest that in addition to imparting flavor to the food, they possess potential health benefits by inhibiting the lipid peroxidation.  相似文献   

2.
The effect of dietary supplementation of spice-active principles, curcumin (0.2%), capsaicin (0.015%), and piperine (0.02%) on the activities of the liver drug-metabolizing enzyme system was examined. All the 3 dietary spice principles significantly stimulated the activity of aryl hydroxylase. A synergistic action of dietary curcumin and capsaicin with respect to stimulating the activity of aryl hydroxylase was also evidenced when fed in combination. The activity of N-demethylase essentially remained unaffected by dietary curcumin, capsaicin, or their combination, but was significantly lowered as a result of piperine feeding. Uridine dinucleotide phosphate (UDP)-glucuronyl transferase activity was decreased by dietary piperine and the combination of curcumin and capsaicin. NADPH-cytochrome c reductase activity was significantly decreased by dietary piperine. The levels of hepatic microsomal cytochrome P450 and cytochrome b5 were not influenced by any of the dietary spice-active principles. These spice-active principles were also examined for their possible in vitro influence on the components of the hepatic drug-metabolizing enzyme system in rat liver microsomal preparation. Piperine significantly decreased the activity of liver microsomal aryl hydroxylase activity when included in the assay medium at 1 x 10(-6) mol/L, 1 x 10(-5) mol/L, and 1x 10(-4) mol/L level. Lowered activity of N-demethylase was observed in presence of capsaicin or piperine at 1 x 10(-6) mol/L in the assay medium. Hepatic microsomal glucuronyl transferase activity was significantly decreased in vitro by addition of capsaicin or piperine. Capsaicin and piperine brought about significant decrease in liver microsomal cytochrome P450 when included at 1 x 10(-6) mol/L and 1 x 10(-5) mol/L, the effect being much higher in the case of piperine. The results suggested that whereas the 3 spice principles have considerable similarity in structure, piperine is exceptional in its influence on the liver drug-metabolizing enzyme system. The study also indicated that a combination of curcumin and capsaicin does not produce any significant additive effect on the liver drug-metabolizing enzyme system.  相似文献   

3.
Fungi and aflatoxins associated with spices in the Sultanate of Oman   总被引:4,自引:1,他引:3  
One hundred and five samples of seven spices (cumin, cinnamon, clove, black pepper, cardamom, ginger, and coriander) were purchased from five popular companies in the Sultanate of Oman. The spices were surveyed for the mycoflora and aflatoxins. Twenty fungal species were isolated in which Aspergillus flavus , A. niger . Penicillium , Rhizopus , and Syncephalastrum racemosum were the most dominant. When colony forming units per gm (cfu/gm) of fungi were compared, significant differences were found among spices and companies. Of the seven spices studied, clove was found to be the least contaminated, while cumin was the most contaminated. None of the 15 selected samples of the spices contaminated by A. flavus were found to contain aflatoxins. Nevertheless, nine isolates (45%) of the twenty A. flavus strains screened for aflatoxins were aflatoxigenic. The moisture content of most of the spices was below the maximum standard limit. The results showed that the spices were contaminated by some fungi that might constitute health hazards for humans. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

4.
A wide variety of phenolic compounds and flavonoids present in spices possess potent antioxidant, antimutagenic and anticarcinogenic activities. We examined whether 5-lipoxygenase (5-LO), the key enzyme involved in biosynthesis of leukotrienes is a possible target for the spices. Effect of aqueous extracts of turmeric, cloves, pepper, chili, cinnamon, onion and also their respective active principles viz., curcumin, eugenol, piperine, capsaicin, cinnamaldehyde, quercetin, and allyl sulfide were tested on human PMNL 5-LO activity by spectrophotomeric and HPLC methods. The formation of 5-LO product 5-HETE was significantly inhibited in a concentration-dependent manner with IC(50) values of 0.122-1.44 mg for aqueous extracts of spices and 25-83 microM for active principles, respectively. The order of inhibitory activity was of quercetin>eugenol>curcumin>cinnamaldehyde>piperine>capsaicin>allyl sulfide. Quercetin, eugenol and curcumin with one or more phenolic ring and methoxy groups in their structure showed high inhibitory effect, while the non-phenolic spice principle allyl sulfide showed least inhibitory effect on 5-LO. The inhibitory effect of quercetin, curcumin and eugenol was similar to that of synthetic 5-LO inhibitors-phenidone and NDGA. Moreover, the inhibitory potency of aqueous extracts of spice correlated with the active principles of their respective spices. The synergistic or antagonistic effect of mixtures of spice active principles and spice extracts were investigated and all the combinations of spice active principles/extracts exerted synergistic effect in inhibiting 5-LO activity. These findings clearly suggest that phenolic compounds present in spices might have physiological role in modulating 5-LO pathway.  相似文献   

5.
Cyclic and pseudocyclic instrumental neutron activation analysis (INAA) has been used to determine the Se content of 40 Libyan food items. The selected samples include different varieties of local and imported foods such as wheat and barley products (bran and flours), rice, bread, almond, peanuts, vegetables as bean and peas, tea, coffee, sugar, and commonly used spices such as red and black paper, curry, cumin, mixture of spices, thyme, coriander, and fenugreek. Both conventional and anticoincidence γ-ray spectrometry techniques have been employed. Pseudocyclic INAA in conjunction with anticoincidence counting has been found to provide the most reliable results. The precision of the method has been significantly improved by recycling the samples up to three times. The accuracy has been evaluated by analyzing a number of certified reference materials of varied Se levels. The detection limit has been found to vary between 26 and 90 ppb Se depending on the sample composition. The range of daily dietary intake has been calculated as 13–44 μg of Se per day.  相似文献   

6.
Fifteen spices obtained from common markets were examined for their mould profile. A total of 520 fungal isolates, representing 57 species, were recovered and identified from dried and ground spice samples on three different media using standard dilution plate method. The most heavily contaminated spice samples examined were observed in ginger in order of magnitude of 5325–6800 cfu/g. The most predominant fungal genera encountered were Aspergillus, Penicillium, and Rhizopus. Relative occurrence values of taxa disclosed ranged between 80% for Aspergillusflavus, Aspergillusniger and Penicilliumarenicola, and 10% for some species. Samples obtained from sumac encountered very rare colony counts indicating its antifungal prosperities. The present magnitude of contamination and spectra of mycobiota approximate those reported for similar spice samples. Several potentially mycotoxigenic fungi were isolated from the majority of samples. The present study attracts the attention to potential risk for mycotoxins contamination may be caused as a result of using these spices, especially in great quantities. The study strongly recommends reduction in application of heavily contaminated spices like ginger in food processing and using some others like clove and sumac due to their antimicrobial properties.  相似文献   

7.
A total of 120 different samples belonging to 24 kinds of spices collected from different places atAssiut Governorate (Egypt) were examined for the natural occurrence of mycotoxins. TLC analysis of spice extracts revealed the presence of aflatoxins (8–35 μg/kg) in 16 samples of anise, black pepper, caraway, black cumin, fennel, peppermint, coriander and marjoram, sterigmatocystin (10–23 μg/kg) in ten samples of red pepper, caraway, cumin and marjoram and citrinin (8–12 ⧎g/kg) in two samples of black cumin, while ochratoxin A and zearalenone could not be detected.  相似文献   

8.
This study was designed to evaluate "in vitro" the inhibitory effects of spices and essential oils on the growth of psycrotrophic food-borne bacteria: Aeromonas hydrophila, Listeria monocytogenes and Yersinia enterocolitica. The sensitivity to nine spices and their oils (chilli, cinnamon, cloves, ginger, nutmeg, oregano, rosemary, sage, thyme) was studied. Antibacterial activity was evaluated on liquid and solid medium. Spices: 1% concentration of each spice was added separately to Triptic Soy Broth and then inoculated to contain 10(8)/ml organism and held to 4 degrees C for 7 days. Populations of test organism were determined on Triptic Soy Agar. Oils: Inhibition of growth was tested by using the paper disc agar diffusion method (at 35, 20 and 4 degrees C) and measuring their inhibition zone. MIC was determined by the broth microdilution method. Some culinary spices produce antibacterial activity: inhibition of growth ranged from complete (cinnamon and cloves against A. hydrophila) to no inhibition. Antibacterial inhibition zone ranged from 8 mm to 45 mm: thyme essential oil showed the greatest inhibition against A. hydrophila.  相似文献   

9.
Ten oriental spices were analyzed for their element composition using X-ray fluorescence (XRF): nutmeg (Myristica fragrans), coriander (Coriandrum sativum), safflower (Carthamus tinctorius), caraway (Carum carvi), Sicilian sumac (Rhus coriaria), aniseed (Anisum vulgare), black pepper (Piper nigrum), cardamom (Elettaria cardamomum), cumin (Cuminum cyminum) and nigella (Nigella sativum). The spices were found to contain the following elements: Mg, Al, Si, P, S, Cl, K, Ca, Ti, Mn, Fe, Cu and Zn, with varying concentrations. Mutagenic studies using Salmonella typhimurium strains TA97a, TA98, TA100, and TA102 showed that the above spices have no base pair substitution mutagenic activity. However, a weak frameshift mutagenicity has been shown by nutmeg and a very weak oxidative mutagenic action has been revealed by cumin.  相似文献   

10.
Ochratoxin A (OTA) is a mycotoxin produced mostly by several species of Aspergillus and Penicillium. OTA is nephrotoxic in all animal species in which it has been tested and is cancerogenic in rodents. It is associated with Balkan endemic nephropathy. It is naturally present in many crop products such as cereals (barley, wheat, maize) and dried fruits, spices, coffee, wine, olives, and cocoa. The aim of this study was to assess the contamination of three Ivoirian spices with OTA (ginger, chili, and pepper) widely consumed by the population. A total of 90 spice samples (ginger: n?=?30; chili: n?=?30; pepper n?=?30) was taken from various sales outlets of Abidjan. OTA was quantified using an HPLC apparatus coupled with a fluorimetric detector. The chili and ginger samples were contaminated with OTA at a mean concentration of 57.48?±?174 and 0.12?±?0.15 μg/kg, respectively. No contamination of the pepper samples was detected. Eight (26.67 %) of the chili samples exceeded the maximum limit of 15 μg/kg established by European regulation. These results should serve as an alert on the risk to the consumer population of these products that are highly contaminated with OTA.  相似文献   

11.
Mutagenic activity of south Indian food items.   总被引:1,自引:0,他引:1  
Dietary components and food dishes commonly consumed in South India were screened for their mutagenic activity. Kesari powder, calamus oil, palm drink, toddy and Kewra essence were found to be strongly mutagenic; garlic, palm oil, arrack, onion and pyrolysed portions of bread toast, chicory powder were weakly mutagenic, while tamarind and turmeric were not. Certain salted, sundried and oil fried food items were also mutagenic. Cissus quadrangularis was mutagenic, while 'decoctions' of cumin seeds, aniseeds and ginger were not. Several perfumes, essential oils and colouring agents, which are commonly used were also screened and many of them exhibited their mutagenic potential by inducing the 'reverse mutation' in Salmonella typhimurium tester strains.  相似文献   

12.
The multifunctional cytochrome P450 monooxygenases P450-1 and P450-2 from Fusarium fujikuroi catalyze the formation of GA14 and GA4, respectively, in the gibberellin (GA)-biosynthetic pathway. However, the activity of these enzymes is qualitatively and quantitatively different in mutants lacking the NADPH:cytochrome P450 oxidoreductase (CPR) compared to CPR-containing strains. 3beta-Hydroxylation, a major P450-1 activity in wild-type strains, was strongly decreased in the mutants relative to oxidation at C-6 and C-7, while synthesis of C19-GAs as a result of oxidative cleavage of C-20 by P450-2 was almost absent whereas the C-20 alcohol, aldehyde and carboxylic acid derivatives accumulated. Interaction of the monooxygenases with alternative electron transport proteins could account for these different product distributions. In the absence of CPR, P450-1 activities were NADH-dependent, and stimulated by cytochrome b5 or by added FAD. These properties as well as the decreased efficiency of P450-1 and P450-2 in the mutants are consistent with the participation of cytochrome b5:NADH cytochrome b5 reductase as redox partner of the gibberellin monooxygenases in the absence of CPR. We provide evidence, from either incubations of GA12 (C-20 methyl) with cultures of the mutant suspended in [18O]H2O or maintained under an atmosphere of [18O]O2:N2 (20:80), that GA15 (C-20 alcohol) and GA24 (C-20 aldehyde) are formed directly from dioxygen and not from hydrolysis of covalently enzyme-bound intermediates. Thus these partially oxidized GAs correspond to intermediates of the sequential oxidation of C-20 catalyzed by P450-2.  相似文献   

13.
Pungent spices are well-recognized for their aromatic and pungent nature; however, relatively little is known about their pungent or ‘burning’ responses. Therefore, this research was undertaken to characterize oral pungency of the principal irritants or red pepper (capsaicin), black pepper (piperine), cinnamon (cinnamaldehyde), cumin (cuminaldehyde), cloves (eugenol), ginger (ginger oleoresin), and alcohol (ethanol). These compounds were evaluated for four pungent qualities (burning, tingling, numbing, overall), two temporal qualities (lag time, overall duration), and three spatial qualities (longitudinal location, lateral location, localized/diffuse). The pungency of cinnamaldehyde was primarily burning and tingling. It had a quick onset and rapid decay. The pungency of eugenol had a long-lasting, predominantly numbing effect. The pungency piperine, capsaicin and ginger were primarily burning, but had different temporal and spatial responses. The pungency of ethanol was most diffuse in nature, with some burning and tingling sensations. It had the shortest perceived onset and overall duration. The pungency of cuminaldehyde was equally burning, tingling and numbing.  相似文献   

14.
In the preceding paper, evidence was presented that rat liver microsomes contain two structurally related isozymes of cytochrome P450, namely cytochromes P450a and P450m, that can both catalyze the 7 alpha-hydroxylation of testosterone. The aim of the present study was to determine the extent to which these two P450 isozymes are responsible for the 7 alpha-hydroxylation of testosterone catalyzed by rat liver microsomes. Four monoclonal antibodies against cytochrome P450a, designated A2, A4, A5, and A7, were prepared in BALB/c mice. Monoclonal antibodies A2 (an IgM), A4 (an IgG2b), and A5 (an IgG1) were determined to be distinct immunoglobulins, whereas A7 could not be distinguished from A5. All of the antibodies were highly specific for cytochrome P450a; none cross-reacted with cytochrome P450m or with 10 other P450 isozymes purified from rat liver microsomes. Competition experiments between unlabeled and horseradish peroxidase-conjugated antibodies revealed that each of the monoclonal antibodies recognized the same epitope on cytochrome P450a. None of the monoclonal antibodies bound to denatured cytochrome P450a, suggesting that they each bound to a spatial epitope. A monospecific, polyclonal antibody against cytochrome P450a was also prepared, as described in the preceding paper. The levels of cytochrome P450a in liver microsomes were determined by single radial immunodiffusion, Western immunoblot (with polyclonal antibody), and enzyme-linked immunosorbent assay with monoclonal antibody. The levels of cytochrome P450a declined with age in male but not female rats, and were inducible up to 10-fold by treatment of rats with various xenobiotics. The levels of cytochrome P450a (but not cytochrome P450m) were also elevated (approximately 3-fold) by thyroidectomy of mature male rats. Near normal levels of cytochrome P450a were restored by treatment of athyroid rats with triiodothyronine, whereas treatment with thyroxine was less effective in this regard. These changes in the levels of cytochrome P450a were highly correlated (r = 0.995) with changes in testosterone 7 alpha-hydroxylase activity. None of the monoclonal antibodies inhibited the catalytic activity of cytochrome P450a when reconstituted with NADPH-cytochrome P450 reductase and lipid. In contrast, the polyclonal antibody not only inhibited the catalytic activity of purified cytochrome P450a, but also completely inhibited (greater than 96%) the 7 alpha-hydroxylation of testosterone catalyzed by liver microsomes from immature and mature rats of both sexes and by liver microsomes from male rats treated with a variety of cytochrome P450 inducers.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

15.
Spices such as coriander, cumin, turmeric, chilli collected from a local market were found to be highly contaminated with bacteria and fungi. A dose of 10 kGy was required to reduce the total bacterial count below detectable levels, while a dose of only 5 kGy was required to eliminate the fungal contamination. Coliforms were totally eliminated at a radiation dose of 5 kGy. During a 6 months storage of irradiated and unirradiated spices, the irradiated spices were found to retain good microbiological quality.  相似文献   

16.
R O Juvonen  M Iwasaki  M Negishi 《Biochemistry》1992,31(46):11519-11523
Cytochrome b5 stimulates the coumarin 7-hydroxylation activity of P450coh. A mutation of Arg-129 in P450coh, however, abolishes the stimulation. Moreover, this mutant P450coh binds loosely to cytochrome b5-conjugated Sepharose 4B, whereas wild-type P450coh binds tightly. Consistent with this, the mutation increases the Ka value for b5 binding approximately 6-fold. The identity of residue 209 also alters the stimulation of the activity of P450coh depending on the type of the substrates used and products formed. Coumarin 7-hydroxylation activity is greatly stimulated by cytochrome b5 only when Phe is at position 209, while cytochrome b5 stimulates testosterone hydroxylation activity of P450coh in which Phe, Asn, Ser or Lys substitutes residue 209. P450coh changes its rate of hydrogen peroxide formation depending on the identity of residue 209 and substrate used. Cytochrome b5 decreases the hydrogen peroxide formation of some P450coh whose activities are stimulated by the cytochrome; however, the decrease does not always result in stimulating the activity. The results indicate, therefore, that residues 129 and 209 play different roles in stimulating P450coh activity by cytochrome b5; Arg-129 is a key residue in the cytochrome b5-binding domain and is essential for the stimulation. Residue 209, however, alters the efficiency of electron transport for substrate oxidation as a residue which resides near the sixth ligand of heme and in the substrate-binding site.  相似文献   

17.
We determined 1) whether the previously observed induction of estradiol secretion in bovine granulosa cells cultured in serum-free conditions is associated with an increase in cytochrome P450 aromatase (P450(arom)) mRNA abundance and 2) whether P450(arom) mRNA levels are responsive to FSH in vitro. Granulosa cells from small (2-4-mm) follicles were cultured in serum-free medium. Estradiol secretion increased with time in culture and was correlated with increased P450(arom) mRNA abundance. Progesterone secretion also increased with time in culture, but P450 cholesterol side-chain cleavage (P450(scc)) mRNA abundance did not. FSH stimulated estradiol secretion and P450(arom) mRNA abundance; the effect was quadratic for both estradiol and P450(arom) mRNA. Estradiol secretion and P450(arom) mRNA levels were correlated. FSH stimulated progesterone secretion and P450(scc) mRNA abundance, although the minimum effective dose of FSH was lower for estradiol (0.1 ng/ml) than for progesterone (10 ng/ml) production. Insulin alone stimulated estradiol secretion and P450(arom) mRNA levels but not progesterone or P450(scc) mRNA abundance. We conclude that this cell culture system maintained both estradiol secretion and P450(arom) mRNA abundance responsiveness to FSH and insulin, whereas P450(scc) mRNA abundance and progesterone secretion were responsive to FSH but not insulin.  相似文献   

18.
Antibody-inhibition experiments established that the induction of cytochrome P450c is largely responsible for the marked increase in liver microsomal 7-ethoxyresorufin O-dealkylation in rats treated with 3-methylcholanthrene, whereas the induction of cytochrome P450b and/or P450e is largely responsible for the marked increase in 7-pentoxy- and 7-benzyloxyresorufin O-dealkylation in rats treated with phenobarbital. When reconstituted with NADPH-cytochrome P450 reductase and lipid, purified cytochrome P450c catalyzed the O-dealkylation of 7-ethoxyresorufin at a rate of approximately 30 nmol/nmol P450/min, which far exceeded the rate catalyzed by either purified cytochromes P450b and P450e or microsomal cytochrome P450c. In contrast, purified cytochrome P450b and P450e were poor catalysts of the O-dealkylation of 7-pentoxy- and 7-benzyloxyresorufin. However, purified cytochrome P450b is an excellent catalyst of several other reactions, such as the N-demethylation of benzphetamine, the hydroxylation of testosterone, and the O-dealkylation of 7-ethoxycoumarin. The low rate of 7-pentoxyresorufin O-dealkylation catalyzed by purified cytochrome P450b did not reflect a requirement for cytochrome b5, and could not be ascribed to an artifact of the method used to measure the formation of resourufin. The catalytic activity of purified cytochrome P450b toward 7-pentoxyresorufin was consistently low over a range of substrate and lipid concentrations, and was not stimulated by sodium deoxycholate (which stimulates the N-demethylation of benzphatamine by purified cytochrome P450b). Evidence is presented which indicates that cytochrome P450c catalyzes the O-dealkylation of both the oxidized and reduced forms of 7-ethoxyresorufin, with perhaps a slight preference for the reduced form. In contrast, cytochrome P450b preferentially catalyzes the O-dealkylation of the oxidized form of 7-pentoxyresorufin. Conditions that favored formation of the reduced form of 7-ethoxyresorufin tended to stimulate its O-dealkylation by purified cytochrome P450c, whereas conditions that favored formation of the reduced form of 7-pentoxyresorufin decreased its rate of O-dealkylation by purified cytochrome P450b. Such conditions included a molar excess of NADPH-cytochrome P450 reductase over cytochrome P450, the presence of superoxide dismutase, and the presence of DT-diaphorase (liver cytosol).(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

19.
20.
AIMS: The objective of this research was to determine the antimicrobial activity of conventional and high-intensity ultrasound-assisted (HI-US) solvent-extracted Thai spices, including ginger (Zingiber officinale Rose), fingerroot (Bosenbergia pandurata Holtt) and turmeric (Curouma longa Linn). METHODS AND RESULTS: Extracts were obtained using hexane, isopropanol and a 7 : 3 isopropanol : hexane mixture as solvents with and without HI-US. The antimicrobial activity of the extracts was assayed against four strains each of Listeria monocytogenes and Salmonella Typhimurium DT 104 using an agar dilution assay. Application of HI-US did not alter antibacterial activity against S. Typhimurium, but antilisterial activity of some HI-US spice extracts decreased. Solvent type affected antimicrobial efficacy of extracts with hexane producing the least antimicrobial activity. Fingerroot extracted with isopropanol-hexane and without HI-US had the best antilisterial effect while HI-US-isopropanol fingerroot extract had the greatest antimicrobial efficacy against S. Typhimurium. CONCLUSIONS: Application of HI-US reduced time of extraction to 5 min, compared with the 24 h required for conventional extraction and maintained antimicrobial activity against Salmonella but slightly reduced activity against Listeria. SIGNIFICANCE AND IMPACT OF THE STUDY: HI-US in combination with proper solvent selection may offer a new tool to optimize extraction of spice essential oil for use as antimicrobial agents, and reduce processing time and costs.  相似文献   

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