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21.
《Bioscience, biotechnology, and biochemistry》2013,77(6):1166-1170
The present study explored the possibility that aroma components generated by the oxidation of olive oil may enhance the palatability of olive oil. Using a mouse behavioral model, we found that olive oil oxidized at room temperature for 3 weeks after opening the package, and heated olive oil were both significantly preferred over non-oxidized olive oil. Furthermore, this preference was enhanced with an additive of oxidized refined olive oil flavoring preparation at a certain concentration. These results suggest that the aroma of oxidized fat might be present in most fats, and might act as a signal that makes possible the detection of fats or fatty acid sources. 相似文献
22.
Bioremediation of oil polluted aquatic systems and soils with novel preparation `Rhoder' 总被引:4,自引:0,他引:4
This paper summarises the experience accumulated duringthe field application of biopreparation `Rhoder' (solely or in a combinationwith preliminary mechanical collection of free oil) for remediation of oil polluted aquatic systems and soils in the Moscow region and Western Siberia during 1994–1999.It was demonstrated that `Rhoder' had a very high efficiency (>99%) for bioremediation of the open aquatic surfaces (100 m2 bay of the River Chernaya, two 5,000 m2 lakes in Vyngayakha) at initial level of oil pollution of 0.4–19.1 g/l. During remediation of the wetland (2,000 m2) in Urai (initial level of oil pollution of 10.5 g/l), a preliminary mechanical collection of oil was applied (75% removal) followed by a triple treatment with `Rhoder'. It resulted in an overall treatment efficiency of 94%. Relatively inferior results of bioremediation of the 10,000 m2 wetland in Vyngayakha (65% removal) and the 1,000 m2 marshy peat soil in Nizhnevartovsk (19% removal) can be attributed to the very high initial level of oil pollution (24.3 g/l and >750 g/g dry matter, respectively) aggravated by the fact that it was impossible to apply a preliminary mechanical collection of oil on these sites. A possible strategy for remediation of such heavily polluted sitesis discussed. 相似文献
23.
An acenaphthene-degrading bacterium putatively identified as Pseudomonas sp. strain KR3 and isolated from diesel-contaminated soil in Lagos, Nigeria was investigated for its degradative and biosurfactant production potentials on crude oil. Physicochemical analysis of the sampling site indicates gross pollution of the soil with high hydrocarbon content (2100 mg/kg) and detection of various heavy metals. The isolate grew luxuriantly on crude oil, engine oil and acenaphthene. It was resistant to septrin, amoxicillin and augmentin but was susceptible to pefloxacin, streptomycin and gentamycin. It was also resistant to elevated concentration of heavy metals such as 1–15 mM lead, nickel and molybdenum. On acenaphthene, the isolate exhibited specific growth rate and doubling time of 0.098 day?1 and 3.06 days, respectively. It degraded 62.44% (31.2 mg/l) and 91.78% (45.89 mg/l) of 50 mg/l acenaphthene within 12 and 21 days. On crude oil, the specific growth rate and doubling time were 0.375 day?1 and 1.85 days with corresponding percentage degradation of 33.01% (903.99 mg/l) and 87.79% (2403.71 mg/l) of crude oil (2738.16 mg/l) within 9 and 18 days. Gas chromatographic analysis of residual crude oil at the end of 18 days incubation showed significant reductions in the aliphatic, alicyclic and aromatic fractions with complete disappearance of benzene, propylbenzene, pristane, phytane, and nC18-octadecane fractions of the crude oil. The isolate produced growth-associated biosurfactant on crude oil with the highest emulsification index (E24) value of 72% ± 0.23 on Day 10 of incubation. The partially purified biosurfactant showed zero tolerance for salinity and had its optimal activity at 27°C and pH 2.0. 相似文献
24.
Simone Caroline Cappellari Birgit Harter-Marques Pia Aumeier Wolf Engels 《Biotropica》2009,41(6):721-729
Floral characteristics often indicate the pollinators' functional group visiting the plant and the pollination syndromes associated with them. This idea has been challenged in the past decades due to increasing evidence that most plants, including those exhibiting floral syndromes, are visited by large arrays of species that differ in their effectiveness as pollinators. Our study focuses on Mecardonia tenella (Plantaginaceae) from the Araucaria forest of southern Brazil, which exhibits characteristics of the oil flower pollination syndrome. However, it is visited by three types of functional groups of bees: male orchid bees, oil-collecting bees, and pollen-seeking bees. The relative contribution of each functional group to the plant's reproductive success was estimated based on their pollen load, visitation frequency, and morphology. We assessed resources, phenology, and breeding system of M. tenella . Our results indicate that flowers lack nectar, but volatiles, lipids, and pollen are resources that can be gathered by visitors. This combination of floral traits and visitors' assemblage makes M. tenella a challenge to the concept of pollination syndromes. Our findings indicate that the current interactions may not reflect the circumstances under which some floral traits of this plant were selected. 相似文献
25.
Mukhopadhyay I Nazir A Mahmood K Saxena DK Das M Khanna SK Chowdhuri DK 《Cell biology and toxicology》2002,18(1):1-11
The effect of argemone oil on hsp70expression and tissue damage was investigated by studying β-galactosidase activity, Western blotting and hybridization, and
trypan blue staining in the larval tissues of transgenic Drosophila melanogaster(hsp70-lacZ)Bg
9. Different concentrations of argemone oil were mixed with food and third-instar larvae were allowed to feed on them for different
time intervals (2, 4, 24, and 48 h). Argemone oil was found to induce hsp70even in the lowest concentration of the adulterant while maximum tissue damage was observed in the higher two treatment groups.
Malpighian tubules and midgut tissue reflected maximum damage as evidenced by both high β-galactosidase activity and trypan
blue staining in these tissues. A prior temperature shock treatment to the larvae was enough to protect the larvae from argemone
oil-induced tissue damage as evidenced by little or no trypan blue staining. The present study suggests the cytotoxic potential
of argemone oil and further strengthens the evidence for the use of hsp70as a biomarker in risk assessment.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
26.
采用MTT法检测细胞活力,用倒置显微镜、荧光显微镜和扫描电子显微镜观察细胞形态与结构的变化,用激光共聚焦显微镜观察细胞微管的分布,从而研究了野艾蒿挥发油对HeLa人宫颈癌细胞形态与结构的影响。结果表明:(1)野艾蒿挥发油对HeLa癌细胞的增殖有明显的抑制作用,呈剂量和时间依赖性。(2)野艾蒿挥发油处理HeLa癌细胞24h后,100、200μg/mL实验组细胞体积缩小,核染色质凝集、微绒毛消失、细胞表面有泡状突起,微管解聚,呈现典型的凋亡特征;400μg/mL实验组细胞膜破裂、胞浆内含物外泄,呈明显的坏死特征。(3)野艾蒿挥发油具有抑制HeLa癌细胞增殖的作用,低、中浓度的野艾蒿挥发油诱导细胞凋亡,而高浓度的野艾蒿挥发油引起细胞坏死。 相似文献
27.
The potential of Mg(x)Co(2-)(x)O(2) as heterogeneous reusable catalyst in transesterification of palm oil to methyl ester was investigated. The catalyst was prepared via co-precipitation of the metal hydroxides at different Mg-Co ratios. Mg(1.7)Co(0.3)O(2) catalyst was more active than Mg(0.3)Co(1.7)O(2) in the transesterification of palm oil with methanol. The catalysts calcined at temperature 300 °C for 4 h resulted in highly active oxides and the highest transesterification of 90% was achieved at methanol/oil molar ratio of 9:1, catalyst loading of 5.00 wt.%, reaction temperature of 150 °C and reaction time of 2 h. The catalyst could easily be removed from reaction mixture, but showed 50% decrease in activity when reused due to leaching of active sites. 相似文献
28.
In trials conducted in Benin, conidia of Beauveria bassiana were evaluated as a control method against the cowpea weevil, Callosobruchus maculatus , in stored cowpea. In the first trial using a high artificial infestation of C. maculatus in 8-kg batches of cowpea in jerry cans under typical conditions, concentrations of 1 × 109 and 1 × 1011 conidia kg−1 were compared with lemon grass oil at 2 mL kg−1 and the synthetic pesticide mixture of 1.5% pirimiphos methyl + 0.05% deltamethrin at 0.5 g kg−1 . After 2 months of storage, seed losses (SD) were 20.63 (5.3)% in the untreated control, 8.04 (3.2)% in the low-dose B. bassiana group, 3.12 (1.3)% in the high-dose B. bassiana group, 2.52 (0.4)% in the lemon grass oil group and 0% in the pirimiphos methyl + deltamethrin group. In a second trial with natural infestations in 50-kg batches of cowpea in 200-L drums, treatment with B. bassiana 1 × 1011 conidia kg−1 was compared with pirimiphos methyl + deltamethrin at 0.5 g kg−1 . After 6 months of storage on six farms, losses reached 30.76 (1.5)% in the control, 1.28 (0.2)% in the pirimiphos methyl + deltamethrin group and 3.69 (0.6)% in the B. bassiana group. 相似文献
29.
目的:将新疆南疆地区栽种的主要经济作物之一小白杏应用于化妆品领域,发挥其保持皮肤弹性、柔软和透明的功效。方法:以小白杏杏仁油为原料,运用正交实验设计,加入一定量的乳化剂,通过改变乳化温度、时间、转速,使油相与水相搅拌均匀。结果:最佳配方为:杏仁油13%,羊毛脂4%,蜂蜡3%,尿素3%,乳化剂1.5%,温度85℃,时间7 min,转速140 r/min。结论:以新疆小白杏杏仁油为主要原料,可研制适合于干性皮肤的防皲裂护手霜。 相似文献