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71.
Storage at 3 and 18 °C of 'Arbequina' olives (Olea europaea L.) cultivated in hedgerows and harvested manually or mechanically (wine grape harvester) was tested. Fruit characteristics and oil quality were monitored. Mechanical harvesting caused internal fruit damage that induced its rapid softening and decay, but also facilitated obtaining higher amounts of oil, which suffered a rapid deterioration during fruit storage. This oil presented lower tocopherol and phenol contents and lower oxidative stability than the oil extracted from manually harvested olives, but showed similar fatty acid composition. Cold storage (3 °C) delayed all of these deterioration processes. It allowed maintaining the best commercial level of quality ("extra") in the oil from mechanically harvested olives for 10 days. This cold storage could be considered as an alternative to the increase in machinery for processing the growing olive production, due to both hedgerow cultivation and mechanized harvesting.  相似文献   
72.
Instrumental light aging is one of the most important tools for restoration and conservation of historical textiles. It used in testing stability of conservation materials, in addition to its lightening effect during the presentation in the museums. Light fading is an important tool for preparing the aged textile and other polymeric samples especially for archaeological conservation applications. Many fadometers do not give homogeneous exposure for all sample’s areas. This work studies the color changes of silk fabric dyed with turmeric (Curcuma longa L.) mordanted with alum or ferric sulfate. Color change was studied for the exposure periods ranged from five to hundred hours. Three positions of different irradiance levels were measured on the same sample namely (bottom, middle and upper). Individual color change for each position was recorded and studied. The results showed that there is non-homogeneous irradiance distribution due to different positions in fadometer or mordant used.  相似文献   
73.
A total of 36 compounds, which comprised 99.4% of the extract, were identified by gas chromatography and mass spectrometry (GC-MS) in the volatile dichloromethane extract obtained from Egyptian corn silk. The main constituents of the volatile extract were cis-alpha-terpineol (24.22%), 6,11-oxidoacor-4-ene (18.06%), citronellol (16.18%), trans-pinocamphone (5.86%), eugenol (4.37%), neo-iso-3-thujanol (2.59%), and cis-sabinene hydrate (2.28%). Dried Egyptian corn silk was also directly extracted with petroleum ether, ethanol, and water. All extracts from solvent extraction and the volatile extract described above exhibited clear antioxidant activities at levels of 50-400 microg/mL in the 2,2-diphenyl-1-picrylhydrazyl (DPPH)/linoleic acid assay. The ethanol extract inhibited DPPH activity by 84% at a level of 400 microg/mL. All samples tested via the beta-carotene bleaching assay also exhibited satisfactory antioxidant activity with clear dose responses. This study indicates that corn silk could be used to produce novel natural antioxidants as well as a flavoring agent in various food products.  相似文献   
74.
Genetic diversity was investigated in a set of 27 barley genotypes, originated from Egypt, using 23 expressed sequence tag (EST)-derived simple sequence repeats (eSSRs), representatives of the seven barley chromosomes. Ninety-five alleles were detected among all the barley accessions. For 22 polymorphic eSSRs, the number of alleles per locus varied from 2 to 12, with a mean of 4.318 alleles per locus. The lowest and the largest number of alleles per locus among the seven homeologous groups was observed in homeologous group 5H and 4H with 3.00 and 6.33, respectively. The gene diversity increased as the number of alleles increased. Gene diversity for 22 ESTs loci varied from 0.137 for GBM1404 to 0.896 for GBM1015 with an average of 0.563. A significant correlation coefficient between gene diversity and the number of alleles was high, r = 0.741 (P < 0.01). Cluster analysis was conducted based on eSSRs data to group the barley genotypes and to construct a dendrogram. Four groups can be distinguished by truncating the dendrogram at gs value of 0.77.  相似文献   
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The morphogenetic responses to salt stress of Tunisian Populus alba clones were studied in order to promote their plantation in damaged saline areas.One year-old plants of three P.alba clones(MA-104,MA-195 and OG)were subjected to progressive salt stress by irrigation during two consecutive years.The plants were grown in a nursery,inside plastic receptacles containing sandy soil and were irrigated with tap water(control)or 3–6 g/l NaCl solution.During this study,leaf epinasty,elongation rate,vigor,internode length,plant architecture,and number of buds were evaluated.Test clone response was highly dependent on the applied treatment and degree of accommodation.The most pronounced alterations were induced under 6g/l of NaCl treatment including leaf epinasty,leaf elongation rate delay,vigor decrease,internode length shortening,and morphogenetic modifications.These responses were less noticeable in the MA-104 clone with respect to the two other clones.The salt effect induced a delay in the leaf elongation rate on the MA-195 and OG clones leading to an early leaf maturity.The vigour and internode length of the MA-104 clone was less affected than the other clones.The OG clone was the most salt-sensitive thus,it developed shorter branches and more buds number than MA-195 and MA-104.The effect of long-term salt stress was to induce early flowering of the P.alba clones which suggests that mechanism of salt accommodation could be developed.  相似文献   
78.
The composting process of organic wastes consists of the bioconversion of biologically unstable wastes to stabilized products for application to soils. This study was carried out on different soils (brown isohumic soils in Sfax region in southern Tunisia and calcimagnesic soils in Korba region in northern Tunisia). The mineralization process of organic matter is more important in isohumic soils, showing less tenors of fine fractions than in calcimagnesic soils. The study of different humic fractions in amended soils shows that humic acid tenors and the polymerization rates are linked to soil nature. Calcimagnesic soils ensure a more important humification than isohumic soils.  相似文献   
79.
This study investigated the beneficial effect of phytogenic extracts on semen quality, reproductive hormones, thyroid activity, immunity, hepatic antioxidant activity, and fertility in rabbit bucks. We divided 70 bucks into seven groups (10 in each). Group 1 was fed a basal diet (control); groups 2, 3, and 4 were fed the control diet with 30, 60, and 90 mg/kg of turmeric, respectively; and groups 5, 6, and 7 were fed the control diet with 50, 75, and 100 mg/kg of garlic extract, respectively, for 8 weeks. Rectal and skin temperatures decreased, while follicle-stimulating hormone, luteinizing hormone, triiodothyronine, thyroxine, testosterone, immunoglobulin M, tumor necrosis factor-alpha, and interleukin-6 in blood serum and glutathione peroxidase in the liver increased in all groups (p < .05). Garlic extract (100 mg/kg diet) increased adenosine triphosphate and glutathione in the liver tissues. All treatments significantly increased net semen volume, percentages of progressive motility, livability, curled tail, and intact acrosomes of spermatozoa, sperm cell concentration, and outputs of total and motile spermatozoa, while significantly decreased percentage of sperm abnormality. In conclusion, dietary supplementation of turmeric or garlic extract can be used as a suitable tool for enhancing the hepatic antioxidant activity, immunity, and semen quality in rabbit bucks.  相似文献   
80.
The present study aimed at analysing the effect of Khat plant extract on rat testicular development. Thirty-two weaned male albino rats (4 weeks old) were divided into four groups consisting of eight animals each. While control animals received normal saline, rats of groups I, II and III received 100, 200 and 300 mg Khat extract per kg body weight dissolved in distilled water by oral gavage daily for 8 weeks, respectively. Blood samples were collected in separate heparinized tubes by cardiac puncture from each rat and processed for measuring plasma levels of reproductive hormones LH, FSH, testosterone and prolactin. Five-µm sections were stained with haematoxylin and eosin and examined by light microscope. Some sections were immunostained for protamine-1 representing a biomarker for intact sperm differentiation. The present study clearly demonstrated that Khat extract has a pronounced effect on testicular maturation of developing albino rats at both the morphological and functional levels. Khat-treated groups revealed a significantly low serum testosterone level and severe impairment of spermatogenesis when compared with control animals. The current findings also verified, for the first time, that the final stages of sperm maturation (spermiogenesis) were strongly impaired after administration of Khat extract to experimental rats particularly at a higher dose (300 mg/kg body weight). This was proved by the very weak, if any, expression of protamine-1 in the maturing spermatids in Khat-treated rats.  相似文献   
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