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81.
The study carried out in this work concerns the pectic polysaccharides of olive cell walls as present in olive pulp and that remained entrapped in the cellulosic residue after sequential extraction of the cell wall material (CWM) with imidazole, carbonate and KOH aqueous solutions. These polymers, obtained after neutralisation and dialysis of an aqueous suspension of the residue (sn-CR fraction), extracted with 4 M KOH, were arabinan-rich pectic polysaccharides. They accounted for 11–19% of the total pectic polysaccharides found in the olive pulp cell walls of fruits collected in two years and in three stages of ripening (green, cherry and black). The analysis by powder X-ray diffraction highlighted the existence, in all sn-CR fractions, of crystalline phases related with the presence of calcium-pectic polysaccharide complexes (CPPC) occurring in an amorphous carbohydrate network. The relative crystallinity of the CPPC varied linearly with the Ca2+/GalA molar ratio until a maximum of 0.57. Size-exclusion chromatography showed that sn-CR fractions possessed a bimodal molecular weight distribution. The lower molecular weight fraction of sn-CR (Mw = 70–135 kDa) was independent on the ripening stage of olive fruit, whereas the higher molecular weight fraction showed values of 1.1, 0.6–0.9 and 0.5–0.7 MDa, respectively, for green, cherry and black olives. Treatment of the sn-CR pectic polysaccharides with a 2 M imidazole solution disrupted the CPPC crystalline network showing the loss of low molecular weight galacturonan-rich material during dialysis (12–14 kDa cut off) and the decrease of molecular weight of the polymers to roughly half. These results allowed to infer the presence of oligogalacturonides held within cell walls by calcium ions and that the pectic polysaccharides of sn-CR fraction occurred in olive pulp cell walls as calcium bridged macrodimers.  相似文献   
82.
We compared parasitic infection in a crop-raiding and a wild-foraging troop of olive baboons, Papio anubis, in Gashaka Gumti National Park, Nigeria, to quantify how crop raiding may have influenced primate-parasite interactions. We recovered gastrointestinal parasites from fecal samples from all adult individuals in both troops and processed them via formal-ether sedimentation. We compared parasitic species richness, prevalence, output, and load across troops. We recovered 9 parasite taxa. The wild-foraging troop had a significantly higher mean output than the crop-raiding troop for Physaloptera sp., Trichuris sp., and also a significantly higher total helminth load. The crop-raiding troop had a significantly higher mean output for the protozoan Balantidium coli and also showed a higher parasitic species richness, with 9 species recovered compared to the 7 recorded for the wild-foraging individuals. The changes in nutritional intake, behavior, and human proximity caused by crop raiding may have important epidemiological impacts on wild primate populations, and the nature of such impacts may vary across different taxa of parasites.  相似文献   
83.
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   
84.
In the present paper, we have used 2‐DE coupled to MS analysis to examine the molecular variability of the Ole e 1 allergen in three olive cultivars (cvs). Our results confirmed that the predicted polymorphism of Ole e 1 at cDNA level is extended to the expressed protein. The profiles of both the Ole e 1 peptides and the N‐glycan variants significantly changed among cvs. We observed that Picual and Arbequina cvs presented the highest and lowest degree of Ole e 1 polymorphism, respectively. Some of these peptides and N‐glycans were distributed in a cv‐specific manner. The putative implications of this molecular polymorphism in the development of the allergy symptoms are discussed.  相似文献   
85.
Aerobic biological treatment was conducted for the treatment of high strength olive oil mill wastewater (OMW). Two different approaches were used for kinetic modeling of OMW biodegradation. TOC removal and CO2–C evolution were monitored in an open and a closed bioreactor systems, respectively. Gompertz, Refractory organics plus first-order (RFO) and Chen–Hashimoto equations were applied to estimate the kinetic parameters by using the data from bioreactors. Furthermore, change in oxidation stage of carbon was monitored and temperature dependency of OMW biodegradation was investigated based on activation energy. At room temperature, 64% of TOC was removed in the open bioreactor while cumulative CO2–C evolution was 6.32 g L−1 in closed the bioreactor. Higher biodegradation efficiency and kinetic parameters were obtained at 25 °C rather than 10 °C. Gompertz and RFO equations provided better fitting with CO2–C and TOC data, respectively. Experimental and kinetic estimations indicated that OMW constituted of approximately 30% refractory organics. The comparison of two different modeling approaches showed that kinetic modeling based on CO2–C provided better correlation with the experimental data. Temperature coefficient indicated that biological degradation of OMW is slightly dependent on temperature.  相似文献   
86.
A new species, Agistemus aimogastaensis, is described with the aid of optical and Scanning Electron Microscopy. This mite is an important predator of two eriophyid mites (Aceria oleae and Oxycenus maxwelli) in olive orchards (Olea europaea, variety Arauco) in La Rioja Province. The problems related to eriophyids in olive orchards in Argentina are highlighted and photos of the damage on leaves and fruit are included.  相似文献   
87.
The present study focused on development of a sperm cryopreservation protocol for the critically endangered olive barb Puntiussarana (Hamilton, 1822) collected from two stocks within Bangladesh and reared in the Fisheries Field Laboratory, Bangladesh Agricultural University (BAU). The sperm were collected in Alsever’s solution prepared at 296 mOsmol kg−1. Sperm were activated with distilled water (24 mOsmol kg−1) to characterize motility. Maximum motility (90%) was observed within 15 s after activation, and sperm remained motile for 35 s. Sperm activation was evaluated in different osmolalities and motility was completely inhibited when osmolality of the extender was ?287 mOsmol kg−1. To evaluate cryoprotectant toxicity, sperm were equilibrated with 5%, 10% and 15% each of dimethyl sulfoxide (DMSO) and methanol. Sperm motility was noticeably reduced within 10 min, when sperm were equilibrated with 15% DMSO, indicating acute toxicity to spermatozoa and therefore this concentration was excluded in further trials. Sperm were cryopreserved using DMSO at concentrations of 5% and 10% and methanol at 5%, 10% and 15%. The one-step freezing protocol (from 5 °C to −80 °C at 10 °C/min) was carried out in a computer-controlled freezer (FREEZE CONTROL® CL-3300; Australia) and 0.25-ml straws containing spermatozoa were stored in liquid nitrogen for 7–15 days at −196 °C. The highest motility in thawed sperm 61 ± 8% (mean ± SD) was obtained with 10% DMSO. The fertilization and hatching rates were 70% and 37% for cryopreserved sperm, and 72% and 62% for fresh sperm. The protocol reported here can be useful for hatchery-scale production of olive barb. The use of cryopreserved sperm can facilitate hatchery operations, and can provide for long-term conservation of genetic resources to contribute in the recovery of critically endangered fish such as the olive barb.  相似文献   
88.
In this study, physico-chemical modifications and community dynamics and functional role of the resident microbiota during composting of humid husk from a two-phase extraction system (TPOMW) were investigated. High mineralization and humification of carbon, low loss of nitrogen and complete degradation of polyphenols led to the waste biotransformation into a high-quality compost. Viable cell counts and denaturing gradient gel electrophoresis (DGGE) profiling of the 16S rRNA genes showed that the thermophilic phase was characterized by the strongest variations of cell number, the highest biodiversity and the most variable community profiles. The isolation of tannin-degrading bacteria (e.g. Lysinibacillus fusiformis, Kocuria palustris, Tetrathiobacter kashmirensis and Rhodococcus rhodochrous) suggested a role of this enzymatic activity during the process. Taken together, the results indicated that the composting process, particularly the thermophilic phase, was characterized by a rapid succession of specialized bacterial populations with key roles in the organic matter biotransformation.  相似文献   
89.
橄榄叶提取物对大鼠急性炎症和痛觉过敏的研究   总被引:2,自引:0,他引:2  
本文采用鹿角菜胶诱导的大鼠急性炎症模型观察橄榄叶提取物(OLE)的抗炎与镇痛作用及对致炎因子TNF-α和IL-1β的mRNA表达。用鹿角菜胶注射到大鼠右后足内,分别于鹿角菜胶注射前30 min和注射后120 min灌胃给予OLE 100、250和500 mg/kg体重。鹿角菜胶处理后测量足跖肿胀度及痛域。用RT-PCR检测足跖垫内组织TNF-α、IL-1β和IL-10的mRNA表达。结果显示,经灌胃给予OLE100、250和500 mg/kg体重,均能明显降低大鼠后足肿胀度,增加痛域,并明显降低致炎因子TNF-α和IL-1β的mRNA表达。本研究提示OLE具有抗炎和镇痛作用,其作用机制可能与抑制TNF-α和IL-1β的mRNA表达有关。  相似文献   
90.
Pilot-scale constructed wetlands (CW) were constructed and operated to treat pre-treated olive mill wastewater. Pilot-scale units comprising three identical series with four pilot-scale vertical flow CWs were operated for one harvest season in a Greek olive mill plant. The pilot-scale CWs were filled with various porous media (i.e., cobble, gravel, and sand) of different gradations. Two series of pilot-scale units were planted with common reeds and the third (control) was unplanted. Mean influent concentrations were 14,120 mg/L, 2841 mg/L, 95 mg/L, 123 mg/L and 506 mg/L for COD, phenols, ortho-phosphate, ammonia and TKN, respectively. Despite the rather high influent concentrations, the performance of the CW units was very effective since it achieved removals of about 70%, 70%, 75% and 87% for COD, phenols, TKN and ortho-phosphate, respectively. COD, phenol and TKN removal seems to be significantly higher in the planted series, while ortho-phosphate removal shows no significant differences among the three series. Temperature and pollutant surface load seem to affect the removal efficiency of all pollutants. Compared to previous studies, pollutant surface loads applied here were higher (by one or two orders of magnitude). Even though high removal efficiencies were achieved, effluent pollutant concentrations remained high, thus preventing their use for irrigation or immediate disposal into the environment.  相似文献   
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