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101.
For the first time the identification and quantification of phenolic compounds of the Olea europaea L. cv. Chemlali olive were carried out to examine their profile during maturation. The phenolic composition was studied by using reverse-phase high-performance liquid chromatography during all steps of fruit development. Oleuropein is the abundant phenolic compound in Chemlali olive, and its concentration increases during maturation. An indirect relationship between oleuropein content in olive fruit and hydroxytyrosol was observed. Weak changes in the amounts of the other phenolic monomers and flavonoids were also observed. The total phenolic content varied from 6 to 16 g/kg expressed as pyrogallol equivalents. Its highest level was found at the last maturation period. The antioxidant capacity of olive extracts was evaluated by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl. The IC(50) values of the olive extract ranged from 3.2 to 1.5 microg/mL. There was a correlation between antioxidant activity and total phenolic content of samples. The antioxidant activity increased with maturation. This could be attributed to the increase of the tolal phenol level with fruit development. 相似文献
102.
Dellali Mohamed Romeo Michèle Gnassia-Barelli Mauricette Aïssa Patricia 《Water, air, and soil pollution》2004,156(1-4):131-144
Water, Air, & Soil Pollution - From May 1998 to May 1999, the clams Ruditapes decussatus were collected each month at three stations of the Bizerta lagoon. This paper represents a synthesis... 相似文献
103.
Ould El Kebir MV Barnathan G Siau Y Miralles J Gaydou EM 《Journal of agricultural and food chemistry》2003,51(7):1942-1947
If a great number of rays are fished in the Tropical East Atlantic Ocean for their caudal fins, only a small amount of ray flesh is processed. Among them, three species of rays, Dasyatis marmorata, Rhinobatos cemiculus, and Rhinoptera marginata, from the Mauritanian coast have been investigated for the fatty acid composition of their lipids. Gas chromatography and gas chromatography-mass spectrometry allowed identification of 50 molecules from muscles, livers, and gonads of these fishes. Principal component analysis, starting from >50 samples, reveals significant differences in various fatty acid distributions, related to the species and sex of the sampled fish. Some of them are preferentially present in one sex or in both species, whereas the occurrence of others characterizes the male and female of one or two species. The results show that rays are potential resources of polyunsaturated fatty acids (PUFA) and should be used in the diet of local populations. The lipidic fractions contained a high amount of PUFA (up to 30% of the total), mainly composed of docosa-4,7,10,13,16,19-hexaenoic acid, eicosa-5,8,11,14-tetraenoic acid, and eicosa-5,8,11,14,17-pentaenoic acid. 相似文献
104.
Rafi MM Vastano BC Zhu N Ho CT Ghai G Rosen RT Gallo MA DiPaola RS 《Journal of agricultural and food chemistry》2002,50(4):677-684
Herbal therapies are commonly used by patients with cancer, despite little understanding about biologically active chemical derivatives. We recently demonstrated that the herbal combination PC-SPES, which contains licorice root, had anti-prostate cancer activity attributable to estrogen(s) that produced a chemical castration. A recent study also demonstrated that licorice root alone decreased circulating testosterone in men. Other studies demonstrated antitumor activity of PC-SPES in vitro associated with decreased expression of the anti-apoptotic protein Bcl-2 and in patients independent of chemical castration, suggesting that other mechanisms of antitumor activity exist separate from chemical castration. In the present study, we assessed licorice root extract for effects on Bcl-2 to identify novel cytotoxic derivatives. Licorice root extract induced Bcl-2 phosphorylation as demonstrated by immunoblot and G2/M cell cycle arrest, similarly to clinically used antimicrotubule agents such as paclitaxel. Bioassay-directed fractionations resulted in a biologically active fraction for Bcl-2 phosphorylation. HPLC separation followed by mass spectrometry and NMR identified 6 compounds. Only one molecule was responsible for Bcl-2 phosphorylation; it was identified as 1-(2,4-dihydroxyphenyl)-3-hydroxy-3-(4'-hydroxyphenyl) 1-propanone (beta-hydroxy-DHP). The effect on Bcl-2 was structure specific, because alpha-hydroxy-DHP, 1-(2,4-dihydroxyphenyl)-2-hydroxy-3-(4'-hydroxyphenyl) 1-propanone, in contrast to beta-hydroxy-DHP, was not capable of Bcl-2 phosphorylation. Pure beta-hydroxy-DHP induced Bcl-2 phosphorylation in breast and prostate tumor cells, G2/M cell cycle arrest, apoptosis demonstrated by Annexin V and TUNEL assay, decreased cell viability demonstrated by a tetrazolium (MTT) assay, and altered microtubule structure. Therefore, these data demonstrate that licorice root contains beta-hydroxy-DHP, which induced Bcl-2 phosphorylation, apoptosis, and G2/M cell cycle arrest, in breast and prostate tumor cells, similarly to the action of more complex (MW >800) antimicrotubule agents used clinically. 相似文献
105.
M E Hamid G E Mohamed M T Abu Samra A A Hamad 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1991,44(3):273-275
In a flock of 425 female and male Nubian goats in the Khartoum Province, an outbreak of a disease causing sudden death of 18 apparently healthy goats occurred (11 females and 7 males, 3-6 years old). Adult Fasciola gigantica were found in the livers of all goats and in seven of them Cysticercus tenuicollis cysts. These organs showed necrotic and severe histopathological changes. Clostridium novyi type B was isolated from necrotic areas of all livers and found to be highly pathogenic and toxigenic to laboratory animals. The disease was diagnosed as infectious necrotic hepatitis (black disease). Faecal examination revealed the presence of F. gigantica eggs. Lymnaea natalensis snails were found to be prevalent in the water canals. As the Khartoum Province is regarded as an endemic area for black disease, routine vaccination is highly recommended for its control in goats and sheep. 相似文献
106.
Specific antibody to Pseudomonas pseudomallei exotoxin was detected in sheep sera exposed to natural infection. An enzyme-linked immunosorbent assay (ELISA) was used. Serum antitoxin was present in 49.3% of sera obtained from a flock of sheep naturally exposed to P. pseudomallei infection. Among these sera, 17.0% gave titers of 10,000. In contrast, serum antitoxin was present in only 6.0% of sera collected from sheep kept on a melioidosis-free farm. The ELISA reactivity of all positive sera could be completely absorbed with purified P. pseudomallei exotoxin. Similarly, preincubation of the exotoxin-coated wells with specific antiserum inhibited the ELISA reactivity of sheep sera. The results indicate that exotoxin is produced in vivo during infection by P. pseudomallei. 相似文献
107.
A Mohamed Ou Said M G Contrepois M Der Vartanian J P Girardeau 《American journal of veterinary research》1988,49(10):1657-1660
Relative pathogenicity of 151 Escherichia coli isolates from 36 calves with bacteremia after necropsy was studied by measurement of the LD50 after mice were inoculated IP with E coli isolates. Study of virulence factors and markers revealed that the pathogenicity of E coli was associated with the production of hydroxamate siderophores and with resistance to serum bactericidal effects. Production of colicins, including colicin V, and of surface antigen 31A was correlated with virulence. The close association between phenotypic expression of virulence factors and markers was consistent with a hypothesis of a localization of genes coding for virulence factors and markers on the same plasmid. 相似文献
108.
The treatment of synchronized cells of the green alga Chlorella fusca under photoautotrophic conditions with metflurazon (SAN H 6706; 4-chloro-5-dimethylamino-2-(α,α,α-trifluoro-m-tolyl-3(2H)-pyridazinone)) induces a bleaching process and results in white-appearing cells. This process of bleaching was followed by quantitative analysis of cell growth and cell division, photosynthetic oxygen evolution, respiratory oxygen consumption, and of pigment pattern at 0, 6, 12, 18, 24, 48, and 72 hr after incubation with different concentrations of metflurazon. Increasing concentrations of metflurazon gradually affected cell growth of Chlorella measured as increase in cell diameter. Cell division was inhibited completely with 1, 10, and 100 μM metflurazon. Photosynthetic oxygen evolution and respiratory oxygen consumption were not inhibited by 1 μM metflurazon during the first 6 hr; after this time a gradually increased inhibition was observed. Both parameters were inhibited by 100 μM metflurazon immediately after herbicide addition. A detailed analysis of the pigment content during the bleaching process revealed that: (a) The bleaching of Chlorella cells by metflurazon is not a simple photochemical process like the photobleaching of boiled cells, but is directed by the active metabolism of Chlorella itself. (b) The bleaching process is characterized by two phases: an accumulation of pigments followed by their degradation. The accumulation phase extends to 6 hr after herbicide addition. (c) During the accumulation phase, chlorophyll is accumulated to 380 and 106% in cells treated with 1 and 100 μM metflurazon, respectively, compared to the initial pigment content. The breakdown of chlorophyll, however, during the degradation phase is 5 times faster in the 1 μM treatment than in the 100 μM treatment. This difference resulted in the faster appearance of white cells with the low metflurazon concentration. (d) During the accumulation phase in the 1 μM treatment, the biosynthesis of chlorophylls, xanthophylls, and carotenes is inhibited by 56, 74, and 78%, respectively, when compared to a nontreated control. When related to the initial amounts, chlorophylls, xanthophylls, and carotenes are accumulated to 380, 230, and 153%, respectively. However, the synthesis of violaxanthin is specifically inhibited, followed by α-carotene. During the degradation phase, violaxanthin and α-carotene again, are the most rapidly disappearing pigments. Continuous culturing of white Chlorella cells resulted in a regeneration to green cells after 96, 240, 384 hr for 1, 10, and 100 μM metflurazone, respectively. The bleaching of Chlorella by metflurazon is evidently dependent on a functioning metabolism and is itself a regulated disassembly of the photosynthetic apparatus, which is reversible and not lethal. 相似文献
109.
110.