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1.
Lipase (triacylglycerol acylhydrolase; EC 3.1.1.3) is the first enzyme of the degradation path of stored triacylglycerols (TAGs). In olive fruits, lipase may determine the increase of free fatty acids (FFAs) which level is an important index of virgin olive oil quality. However, despite the importance of virgin olive oil for nutrition and human health, few studies have been realized on lipase activity in Olea europaea fruits. In order to characterize olive lipase, fruits of the cv. Ogliarola, widely diffused in Salento area (Puglia, Italy), were harvested at four stages of ripening according to their skin colour (green, spotted I, spotted II, purple). Lipase activity was detected in the fatty layer obtained after centrifugation of the olive mesocarp homogenate. The enzyme exhibited a maximum activity at pH 5.0. The addition of calcium in the lipase assay medium leads to an increment of activity, whereas in the presence of copper the activity was reduced by 75%. Furthermore, mesocarp lipase activity increases during olive development but declined at maturity (purple stage). The data represent the first contribution to the biochemical characterization of an olive fruit lipase associated to oil bodies.  相似文献   

2.
Summary Polyionic hydrogels have been prepared by complexation of chitosan and xanthan. These hydrogels have been used to immobilize lipase from porcine pancreas (E.C. 3.1.1.3). Immobilization efficiency varied between 90 and 99% of initial activity. Immobilized lipase retained its activity towards hydrolysis of olive oil in water as an emulsion and of olive oil in isooctane.  相似文献   

3.
Lipoxygenase pathway in olive callus cultures (Olea europaea)   总被引:1,自引:0,他引:1  
Stimulation of the lipoxygenase pathway in olive fruit initiates a cascade of reactions that begins with the regio- and stereospecific di-oxygenation of polyunsaturated fatty acids containing a cis, cis-1,4 pentadiene moiety. Later products of the pathway include volatiles that influence the organoleptic properties of harvested olive oil. In this study, we have investigated lipoxygenase activity in olive callus cultures, and found that there is evidence of several isoforms of the enzyme with different pH optima and substrate specificities. Endogenous lipoxygenase activity was detected throughout the growth cycle of olive callus, particularly during the log phase of growth, suggesting that olive lipoxygenases are intimately involved in growth. The most prominent lipoxygenase activity in tissue cultures was found to be soluble but significant activities were detected in the plastid fraction. In addition, hydroperoxide lyase (HPL) activity was measured in the calli; both 13- and 9-HPL activities were found which were particulate.  相似文献   

4.
Mediterranean diet includes a relatively high fat consumption mostly from monounsaturated fatty acids mainly provided by olive oil, the principal source of culinary and dressing fat. The beneficial effects of olive oil have been widely studied and could be due to its phytochemicals, which have been shown to possess anti-inflammatory properties. Lubricin is a chondroprotective glycoprotein and it serves as a critical boundary lubricant between opposing cartilage surfaces. A joint injury causes an initial flare of cytokines, which decreases lubricin expression and predisposes to cartilage degeneration such as osteoarthritis. The aim of this study was to evaluate the role of extra-virgin olive oil diet and physical activity on inflammation and expression of lubricin in articular cartilage of rats after injury. In this study we used histomorphometric, histological, immunocytochemical, immunohistochemical, western blot and biochemical analysis for lubricin and interleukin-1 evaluations in the cartilage and in the synovial fluid. We report the beneficial effect of physical activity (treadmill training) and extra-virgin olive oil supplementation, on the articular cartilage. The effects of anterior cruciate ligament transection decrease drastically the expression of lubricin and increase the expression of interleukin-1 in rats, while after physical activity and extra-virgin olive oil supplemented diet, the values return to a normal level compared to the control group. With our results we can confirm the importance of the physical activity in conjunction with extra-virgin olive oil diet in medical therapy to prevent osteoarthritis disease in order to preserve the articular cartilage and then the entire joint.  相似文献   

5.
The olive (Olea europaea L.) is a widely-distributed plant that originated in the Mediterranean region. Its fruit is commonly used to produce olive oil, table olives, and other by-products. The main nutrient of the olive fruit is fat, predominantly monounsaturated fatty acids (MUFA). Olives are also rich in carbohydrates, vitamins, and minerals. Increasing numbers of investigations show that the health benefits of the ‘Mediterranean diet’ are associated with lower incidences of chronic degenerative diseases and higher life expectancy. These benefits have been attributed to the dietary consumption of olive oil. Furthermore, epidemiological data suggest that phenolic components and other antioxidants in olive oil are responsible for some of these benefits. Remarkably, these minor components play significant roles in reducing the incidences of atherosclerosis, cardiovascular disease, neurodegenerative diseases, and certain types of cancer. We reviewed the main olive products and the nutritional composition of olive oil focusing on fatty acids, phenolic compounds, and other antioxidants. We also discuss the chief chemical constituents relevant to the biological activity of olive oil, the metabolism and bioavailability of olive oil phenolic compounds, and the antioxidant activity of metabolites. Finally, we outline recent advances, potential applications, and limitations of developments in the olive oil industry, aiming to provide a theoretical basis for further research and to broaden the prospect of its application to healthy diets.  相似文献   

6.
In the present work we have studied the effects of feeding either olive or sunflower oil on lipid composition and desaturase activities of duodenal mucosa microsomes. Duodenal microsomes prepared from dogs fed the sunflower oil diet showed higher percentages of saturated, of linoleic and of n - 3 polyunsaturated fatty acids as well as lower levels of oleic, dihomo-gamma-linolenic and arachidonic acids in phosphatidylcholine and phosphatidylethanolamine than those prepared from animals fed the olive oil diet. In sphingomyelin, the dietary supplementation did not produce significant differences between the two groups. The cholesterol/phospholipid molar ratio was higher in the sunflower oil group than in the olive oil group. The in vitro delta 9-desaturase activity was higher in microsomes from the olive oil dogs. The delta 6-desaturase activity was similar in microsomes from the two groups and lower than that found for delta 9-desaturase activity. Desaturase activities were higher in duodenal microsomes than those previously found for liver microsomes.  相似文献   

7.
Previous studies have shown the antiinflammatory, antioxidant and antiangiogenic properties by pure olive oil polyphenols; however, the effects of olive oil phenolic fraction on the inflammatory angiogenesis are unknown. In this study, we investigated the effects of the phenolic fraction (olive oil polyphenolic extract, OOPE) from extra virgin olive oil and related circulating metabolites on the VEGF-induced angiogenic responses and NADPH oxidase activity and expression in human cultured endothelial cells. We found that OOPE (1–10 μg/ml), at concentrations achievable nutritionally, significantly reduced, in a concentration-dependent manner, the VEGF-induced cell migration, invasiveness and tube-like structure formation through the inhibition of MMP-2 and MMP-9. OOPE significantly (P<0.05) reduced VEGF-induced intracellular reactive oxygen species by modulating NADPH oxidase activity, p47phox membrane translocation and the expression of Nox2 and Nox4. Moreover, the treatment of endothelial cells with serum obtained 4 h after acute intake of extra virgin olive oil, with high polyphenol content, decreased VEGF-induced NADPH oxidase activity and Nox4 expression, as well as, MMP-9 expression, as compared with fasting control serum. Overall, native polyphenols and serum metabolites of extra virgin olive oil rich in polyphenols are able to lower the VEGF-induced angiogenic responses by preventing endothelial NADPH oxidase activity and decreasing the expression of selective NADPH oxidase subunits. Our results provide an alternative mechanism by which the consumption of olive oil rich in polyphenols may account for a reduction of oxidative stress inflammatory-related sequelae associated with chronic degenerative diseases.  相似文献   

8.
Health benefits of lycopene from tomato products have been suggested to be related to its antioxidant activity. Dietary fat may influence the absorption and hence the plasma levels and antioxidant activity of lycopene. In the present study, we have compared the effect of consumption of tomato products with extra-virgin olive oil vs. tomato products plus sunflower oil on plasma lycopene and antioxidant levels. Results show that the oil composition does not affect the absorption of lycopene from tomato products because similar levels of plasma lycopene (mean +/- SD) were obtained on feeding tomatoes (providing approximately 46 mg lycopene/d) for 7 d with either olive oil (0.66 +/- 0.26 vs 1.20 +/- 0.20 micromol/l, p <.002) or sunflower oil (0.67 +/- 0.27 vs. 1.14 micromol/l, p <.001). However, consumption of tomato products with olive oil significantly raised the plasma antioxidant activity (FRAP) from 930 +/- 150 to 1118 +/- 184 micromol/l, p <.01) but no effect was observed when the sunflower oil was used. The change (supplementation minus start values) in FRAP following the consumption of tomato products with oil was significantly higher for olive oil (190 +/- 101) than for sunflower oil (-9.6 +/- 99, p <. 005). In conclusion, the results of the study show that consumption of tomato products with olive oil but not with sunflower oil improves the antioxidant activity of the plasma.  相似文献   

9.
Olea europaea preparations are traditionally employed in a variety of troubles, including skin infections. Olive extracts and some of their pure compounds have shown antimicrobial activity in vitro. The present study deals with the antifungal activity of some aliphatic aldehydes from olive fruit [hexanal, nonanal, (E)-2-hexenal, (E)-2-heptenal, (E)-2-octenal, (E)-2-nonenal] against Tricophyton mentagrophytes (6 strains), Microsporum canis (1 strains) and Candida spp. (7 strains). The capability of these substances to inhibit elastase, a virulence factor essential for the dermatophytes colonization, and their cytotoxicity on cultures of reconstructed human epidermis, are also described. Aldehydes tested, inhibited the growth of T. mentagrophytes and M. canis in the range of concentration between <1.9 and 125 microg/ml; the unsaturated aldehydes showed the most broad spectrum of activity in that inhibited all strains tested. None of the aldehydes exhibited activity against Candida spp. strains. (E)-2-octenal and (E)-2-nonenal inhibited the elastase activity in a concentration-dependent manner; the anti-elastase activity suggests an additional target of the antimicrobial activity of these compounds. Aldehydes were devoid of cytotoxicity on cultures of human reconstructed epidermis. The antifungal activity of the aldehydes from olive fruit here reported, substantiates the use of olive and olive oil in skin diseases and suggests that these natural compounds could be useful agents in the topical treatment of fungal cutaneous infections.  相似文献   

10.
We recorded bat activity on Zakynthos island (Greece) to test the hypotheses that (1) olive ( Olea europea ) groves and native woodlands provide comparable foraging habitat for insectivorous bats, (2) lower foraging activity occurs in olive groves treated with insecticide chemicals. We acoustically sampled bat activity (passes per minute) in four wooded habitats (organic and non-organic olive groves, oak woodland ( Quercus ilex and Quercus coccifera ) and pine ( Pinus halepensis ) woodland from June to August 2005. Habitat type did not affect overall bat activity. A single application of insecticide chemicals annually did not affect activity over traditional olive groves. Habitat use on the island differed in several ways from that reported in studies at mainland sites. Most strikingly, pine woodland supported higher bat activity than expected relative to other habitat types, and we recorded unexpectedly high levels of M. capaccinii activity in woodland habitats. We suggest that traditional olive groves buffer some bat species from the effects of deforestation. Conservation plans for Mediterranean bats should consider the biodiversity value of these groves along with the need to conserve small woodland patches. Finally, understanding island-specific patterns of habitat use is essential to bat conservation on small off-shore islands.  相似文献   

11.
Diet supplementation with olive oil exerts beneficial effects on an organism, even if an increase in the level of hepatic lipids has been concomitantly observed. This study was therefore designed to investigate whether the stimulation of lipogenesis was responsible for the olive oil-induced hepatic fat accumulation. In mice fed for 8 weeks with an olive oil-enriched diet, an increase of about 2.6 fold in the level of liver triglycerides was found in comparison to animals fed with a corn oil-containing diet. Despite that, no increase in the activities of cytosolic lipogenic enzymes or of the mitochondrial tricarboxylate carrier was found; on the contrary, a decrease in the activity of carnitine palmitoyltransferase I was observed. This impairment of fatty acid oxidation, which was not apparent in corn oil-fed animals, may have had a role in the increase of hepatic lipid content found in the olive oil-fed mice.  相似文献   

12.
橄榄果渣中生物活性成分丰富。本文主要研究橄榄果渣提取物成分及其对灰葡萄孢的抑菌性能。首先以橄榄果渣为原料,采用加热回流法,分别以H2O、50%乙醇、70%乙醇和90%乙醇为提取剂,得到四种提取物并采用HPLC和GC-MS对提取物进行成分分析。其次测定了提取物的总酚含量、抗氧化性和对灰葡萄孢的抑菌性能。研究表明,90%乙醇提取物的酚类含量较高,抗氧化水平优良,并且对灰葡萄孢有明显的抑制作用。该研究为橄榄果渣活性成分在抑菌性能方面的研究提供了一定的理论依据。  相似文献   

13.
本文介绍了微球菌(Micrococcussp)1504胞外脂肪酶的代谢调节模式。发现在发酵培养基中,通过补加长链脂肪酸及其油酯,能提高脂肪酶的生产水平,而中、短链脂肪酸及其酯抑制产酶能力;高浓度的葡萄糖抑制产酶能力;补加不同浓度的橄揽油,适宜补加时间也应不同。水洗细胞脂肪酶的合成受橄榄油和油酸诱导,受葡萄糖和甘油阻遏,并发现脂肪酶的分解代谢阻遏主要发生在转录水平上。  相似文献   

14.
Abstract

OBSERVATIONS ON A SPECIAL CASE OF WOUND HEALING IN AN OLIVE TREE DAMAGED BY LOW TEMPERATURE IN FEBRUARY 1956. — The authors have observed an unusual form of woung healing in an olive tree damaged by low temperature in 1956, and have studied its morphological and anatomical details.

Attention is drawn to the notable ability of olives to recover from low temperature damage, especially through the activity of the subsidiary trunks « corde » characteristic of the olive tree.  相似文献   

15.
主要对华根霉全细胞脂肪酶固态和液态两种发酵过程进行比较,并着重探讨不同培养方式下橄榄油对其合成活力和水解活力的影响。结果表明:液态培养较有利于菌体生长,对脂肪酶的生产也有一定的促进作用。橄榄油的加入不仅有利于菌体生长、提高脂肪酶水解活力,更可使脂肪酶的合成活力显著增加,液态发酵下的效果更为明显。橄榄油在整个发酵过程中可能既作为碳源又是脂肪酶的诱导物。另外,全细胞脂肪酶的水解活力和合成活力在固液态发酵条件下均存在不对应性,表明华根霉可能产性质不同的脂肪酶同功酶。  相似文献   

16.
The antioxidant activity of hydroxytyrosol, hydroxytyrosol acetate, oleuropein, 3,4-dihydroxyphenylelenolic acid (3,4-DHPEA-EA) and 3,4-dihydroxyphenylelenolic acid dialdehyde (3,4-DHPEA-EDA) towards oxidation initiated by 2,2'-azobis(2-amidinopropane) hydrochloride in a soybean phospholipid liposome system was studied. The antioxidant activity of these olive oil phenols was similar and the duration of the lag phase was almost twice that of alpha-tocopherol. Trolox, a water-soluble analogue of alpha-tocopherol, showed the worst antioxidant activity. However, oxidation before the end of the lag phase was inhibited less effectively by the olive oil phenols than by alpha-tocopherol and Trolox. Synergistic effects (11-20% increase in lag phase) were observed in the antioxidant activity of combinations of alpha-tocopherol with olive oil phenols both with and without ascorbic acid. Fluorescence anisotropy of probes and fluorescence quenching studies showed that the olive oil phenols did not penetrate into the membrane, but their effectiveness as antioxidants showed they were associated with the surface of the phospholipid bilayer.  相似文献   

17.
Some biological actions of olive oil phenolics (inhibition of platelet aggregation, decrease of LDL-oxidation, inhibition of bacterial growth and hypertensive action) have been attributed to NOS stimulation in endothelial cells through an increase of cytosolic calcium, notwithstanding the scavenging activity of phenolics on NO and superoxide. In this paper, we determine the concentration of cytosolic calcium in human lymphomonocytes incubated with high concentrations of NO-donors (CysNO) and we evaluate the effects of olive oil phenolics on this parameter. CysNO induces a marked decrease of cytosolic calcium; both olive oil phenolics oppose this action of CysNO. The effects of phenolics and CysNO are independent and additive. (Mol Cell Biochem xxx: 181–184, 2005)  相似文献   

18.
Beta-sitosteryl-D-glucoside and oleuropein isolated from the olive tree (Olea europaea) and their hydrolysed derivatives were tested by a feeding stimulative activity bioassay using the olive weevil (Dyscerus perforatus). Although the steroidal glucoside showed potent feeding stimulative activity, the activity of the aglycone (beta-sitosterol) was significantly lower than that of the glucoside. On the other hand, the difference in the activity between oleuropein, a secoiridoid glucoside, and the hydrolysed derivatives was not significant.  相似文献   

19.
Penicillium candidum grew and produced lipase in a culture medium supplemented with 0.2% olive oil. Significant enzyme production required the presence of olive, oil and was prevented by cycloheximide. Polyacrylamide gel electrophoresis of filtrates from olive oil fermentations gave a single band of lipase activity (MW 80 KDa). Among the olive oil components only oleate allowed significant lipase production. Other carboxylic and saturated fatty acids containing similar or lower numbers of carbon atoms, did not cause derepression of lipase formation.  相似文献   

20.
Changes in the activity of brain antioxidant superoxide dismutases (SOD) were followed in newborn and young female rats 8, 15, 30, 45, 60 and 75 days after birth treated with olive oil. In newborn rats, the content of brain cytosol SOD (CuZnSOD) and mitochondrial SOD (MnSOD) decreased after treatment with olive oil. However, in the brain of rats aged 8 days this effect was lost. The suppressive effect of olive oil on these enzymes reappeared again in 15-day-old rats. In rats aged one month, only the activity of CuZnSOD was reduced after olive oil treatment. In the brain of rats aged 45, 60 and 75 days, neither MnSOD nor CuZnSOD were affected by olive oil. The different effects of olive oil on the brain SOD, during ontogeny suggest that profound changes in the susceptibility of nervous tissue antioxidant enzymes to olive oil take place during sexual maturation.  相似文献   

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