Estimation of the hydrocarbon-oxidizing activity of microorganisms

A method allowing the microorganisms growing on substrates with a low water solubility (oil, fuel oil, resins, and asphalthenes) to be isolated and counted was developed. An advantage of the method is its ability to estimate the oil-utilizing activity of each strain visually according to the decolorized zones formed during its growth on oil products. The sizes of these zones indicate which oil-degrading strain is most active.     

Rapid selection of microorganisms producing extracellular lipases]

A method for rapid selection of microorganisms producing extracellular lipases is described. The method is based on diffusion of the enzyme into agar containing olive oil. The hydrolysis zones revcal by 0,05--0,25% OSO4 solution.     

Improved method for direct screening of true lipase-producing microorganisms with particular emphasis on alkaline conditions

A rapid and effective method for direct detection, selection and testing of microorganisms able to produce both cell-bound and extracellular true lipases is described. The method is based on formation of clearance zones on turbid solid media with emulsified olive oil around or under the colonies, cell fractions or culture supernatant of lipase-producing organisms. The method was successfully applied for the screening and isolation of microorganisms producing alkaline lipases. The article is published in the original.     

Method for selective isolation of Mycobacteria using olive oil emulsified with SDS

This paper describes the demulsification of olive-oil/SDS emulsion (DOSE) method for selective isolation of environmental mycobacteria. A soil sample was suspended in olive oil and centrifuged. The supernatant was emulsified on plates together with SDS solution. After incubation, the colonies that had developed on the plates were surrounded by clear zones. The isolates were identified as genus Mycobacterium, and as belonging to a fast-growing group, by 16S rRNA gene sequence analysis.     

Decidualization in the post-partum uterus of the mouse

Unilaterally ovariectomized mice were allowed to complete one pregnancy before the second ovary was removed and sensitivity to decidualization was induced by hormone administration. The virgin uterine horn and the post-partum horn were stimulated to decidualize by the intraluminal injection of arachis oil. A greater decidual response was found in post-partum horns than in virgin horns. The foci of decidual induction in post-partum horns were regularly spaced reflecting the regular spacing of used and unused areas of the uterus. A focus of decidual induction occurred in 68% of the recently used uterine areas observed, i.e. areas associated with post-partum nodules. When compared with foci of decidualization in adjacent unused areas of the uterus, none of the decidualized used zones showed more decidual tissue, about half showed less decidual tissue and half showed the same amount of decidual tissue. The remaining 32% of used zones were not associated with foci of decidual induction. The results indicate that decidualization can be induced in recently used zones of the uterus using a non-traumatic method of induction, but that used zones are associated with less decidual tissue than unused zones of the post-partum uterus.     

老君庙油田L油层注水时细菌发育的规律

注水是广泛应用的有效采油工艺。在注入水、含油层和地层水中存在着各种微生物。注入的淡水将地层水冲淡,同时带进了微生物和其它物质,加强了微生物在地层中的活动。这是引起注水层堵塞和采油设备腐蚀的重要因素。因此,油层注水后,细菌发育状况的研究不仅具有理论意义,也具有重要的实践价值,早就引起了注意(Beerstecher,1954;Davis,1967;     

Preparation of prospective plant oil derived micro-emulsion vehicles for drug delivery

Biocompatible oil-in-water (o/w) micro-emulsions can be prospective drug delivery vehicles for their capability to solubilize lipophilic (oil soluble) drugs in the dispersed oil. Plant oils are considered suitable for such a purpose. In this study, we have attempted to examine the dispersion of corn, cottonseed, clove, orange and peppermint oils, as well as isopropyl myristate (IPM) in water continuum in presence of surfactants Tween-20, Brij-30 and Brij-92 and co-surfactants ethanol (EtOH) and isopropyl alcohol (iPrOH). Both ternary (oil/surfactant/water) and psedoternary (oil/surfactant + co-surfactant/water) phase diagrams were constructed. The ternary systems produced larger micro-emulsion forming zones than the psedo-ternary systems. The combinations peppermint oil/iPrOH/water, IPM/iPrOH/water and 1:1 (v/v) peppermint oil + IPM/iPrOH/water were found to form fair proportion of single-phase surfactant-less micro-emulsion. The surfactant-aided ternary systems produced larger clear microemulsion zones, compared to pseudo-ternary systems, while the behaviour of surfactant-less systems was intermediate. The prepared systems had shelf life of 1 year and they withstood temperature variations in the range of 4-40 degrees C.     

Antimicrobial activity of the major components of the essential oil of Melaleuca alternifolia

Tea tree oil, or the essential oil of Melaleuca alternifolia , is becoming increasingly popular as a naturally occurring antimicrobial agent. The antimicrobial activity of eight components of tea tree oil was evaluated using disc diffusion and broth microdilution methods. Attempts were also made to overcome methodological problems encountered with testing compounds which have limited solubility in aqueous media. After assessing media with and without solubilizing agents, the disc diffusion method was used to determine the susceptibility of a range of micro-organisms to 1,8-cineole, 1-terpinen-4-ol, ρ-cymene, linalool, α-terpinene, γ-terpinene, α-terpineol and terpinolene. While the disc diffusion method lacked reproducibility, it was considered useful as a procedure for screening for antimicrobial activity. Terpinen-4-ol was active against all the test organisms while ρ-cymene demonstrated no antimicrobial activity. Linalool and α-terpineol were active against all organisms with the exception of Pseudomonas aeruginosa. Minimum inhibitory and minimum cidal concentrations of each component against Candida albicans, Escherichia coli and Staphylococcus aureus were determined using a broth microdilution method. Modifications to this method overcame solubility and turbidity problems associated with the oil components and allowed the antimicrobial activity of each of the components to be quantified reproducibly. There was reasonable agreement between minimum inhibitory concentrations and zones of inhibition. These results may have significant implications for the future development of tea tree oil as an antimicrobial agent.     

Large expansion of oil industry in the Ecuadorian Amazon: biodiversity vulnerability and conservation alternatives

Ecuador will experience a significant expansion of the oil industry in its Amazonian region, one of the most biodiverse areas of the world. In view of the changes that are about to come, we explore the conflicts between oil extraction interests and biodiversity protection and apply systematic conservation planning to identify priority areas that should be protected in different oil exploitation scenarios. First, we quantified the current extent of oil blocks and protected zones and their overlap with two biodiversity indicators: 25 ecosystems and 745 species (whose distributions were estimated via species distribution models). With the new scheme of oil exploitation, oil blocks cover 68% (68,196 km²) of the Ecuadorian Amazon; half of it occupied by new blocks open for bids in the southern Amazon. This region is especially vulnerable to biodiversity losses, because peaks of species diversity, 19 ecosystems, and a third of its protected zones coincide spatially with oil blocks. Under these circumstances, we used Marxan software to identify priority areas for conservation outside oil blocks, but their coverage was insufficient to completely represent biodiversity. Instead, priority areas that include southern oil blocks provide a higher representation of biodiversity indicators. Therefore, preserving the southern Amazon becomes essential to improve the protection of Amazonian biodiversity in Ecuador, and avoiding oil exploitation in these areas (33% of the extent of southern oil blocks) should be considered a conservation alternative. Also, it is highly recommended to improve current oil exploitation technology to reduce environmental impacts in the region, especially within five oil blocks that we identified as most valuable for the conservation of biodiversity. The application of these and other recommendations depends heavily on the Ecuadorian government, which needs to find a better balance between the use of the Amazon resources and biodiversity conservation.     

Naturally Saline Boreal Communities as Models for Reclamation of Saline Oil Sand Tailings

Reclaimed landscapes after oil sands mining have saline soils; yet, they are required to have similar biodiversity and productivity as the predisturbance nonsaline landscape. Given that many species in the boreal forest are not tolerant of salinity, we studied the effects of soil salinity on plant communities in natural saline landscapes to understand potential plant responses during the reclamation process. Vegetation–soil relationships were measured along transects from flooded wetlands to upland forest vegetation in strongly saline, slightly saline, nonsaline, and reclaimed boreal landscapes. In strongly saline landscapes, surface soil salinity was high (>10 dS/m) in flooded, wet‐meadow, and dry‐meadow vegetation zones as compared to slightly saline (<5 dS/m) and nonsaline (<2 dS/m) landscapes. Plant communities in these vegetation zones were quite different from nonsaline boreal landscapes and were dominated by halophytes common to saline habitats of the Great Plains. In the shrub and forest vegetation zones, surface soil salinity was similar between saline and nonsaline landscapes, resulting in similar plant communities. In strongly saline landscapes, soils remained saline at depth through the shrub and forest vegetation zones (>10 dS/m), suggesting that forest vegetation can establish over saline soils as long as the salts are below the rooting zone. The reclaimed landscape was intermediate between slightly saline and nonsaline landscapes in terms of soil salinity but more similar to nonsaline habitats with respect to species composition. Results from this study suggest it may be unrealistic to expect that plant communities similar to those found on the predisturbance landscape can be established on all reclaimed landscapes after oil sands mining.     

Inhibition of quorum sensing regulated bacterial functions by plant essential oils with special reference to clove oil

Aims:  To evaluate quorum sensing (QS) inhibitory activity of plant essential oils using strains of Chromobacterium violaceum (CV12472 and CVO26) and Pseudomonas aeruginosa (PAO1).
Methods and Results:  Inhibition of QS-controlled violacein production in C. violaceum was assayed using disc diffusion and agar well diffusion method. Of the 21 essential oils, four oils showed varying levels of anti-QS activity. Syzygium aromaticum (Clove) oil showed promising anti-QS activity on both wild and mutant strains with zones of pigment inhibition 19 and 17 mm, respectively, followed by activity in cinnamon, lavender and peppermint oils. The effect of clove oil on the extent of violacein production was estimated photometrically and found to be concentration dependent. At sub-MICs of clove oil, 78·4% reduction in violacein production over control and up to 78% reduction in swarming motility in PAO1 over control were recorded. Gas chromatography–mass spectrometry analysis of clove oil indicated presence of many phytocompounds. Eugenol, the major constituent of clove oil could not exhibit anti-QS activity.
Conclusions:  Presence of anti-QS activity in clove oil and other essential oils has indicated new anti-infective activity. The identification of anti-QS phytoconstituents is needed to assess the mechanism of action against both C. violaceum and Ps. aeruginosa .
Significance and Impact of the study:  Essential oils having new antipathogenic drugs principle because of its anti-QS activity might be important in reducing virulence and pathogenicity of drug-resistant bacteria in vivo .     

Dietary fats influence 'open-field' behaviour of male and female laboratory mice

Swiss mice of differing ages (juvenile and adult) and sexes were fed four specially formulated, pelleted diets containing respectively 8% saturated vegetable fat, 8% soya oil, 8% olive oil and 2% soya oil (with identities hidden from the experimenter) or a local commercial chow (3% crude fat) for 3 or 6 weeks. Subjects were individually housed and were assessed under red lighting for behaviour in a modified 'open field' (a 30 x 20 cm box with a black floor). Videotaped records were analysed using 'The Observer' system, quantifying transitions between inner and outer zones, rearing, freezing, grooming and defaecation as well as location in the two equal-sized zones. Clearly, these non-isocaloric diets differed in palatability, producing complex effects on growth as well as physiological and behavioural measures. Many indices were influenced by age, sex, and the duration of dietary exposure. Interactions between factors were common. Defaecation does not seem to provide a useful index of 'emotionality' in this type of study and investigations lacking a wide range of indices seem unlikely to provide unequivocal support for postulated links between dietary lipids and behaviour. The study broadly supports the contention that dietary fats subtly influence mood in mice.     

Effect of Environmental Parameters on Bacterial Degradation of Bunker C Oil, Crude Oils, and Hydrocarbons

Mixed microbial cultures, previously enriched on Bunker C fuel oil, grew on and degraded Bunker C fuel oil at temperatures ranging from 5 to 28 C. At 15 C, 41 to 85% of the benzene-soluble components of Bunker C disappeared after incubation for 7 days; at 5 C the values ranged from 21 to 52% after 14 days of incubation. A Nocardia sp. isolated from a culture enriched on Bunker C oil grew on Venezuelan crude oil, Bunker C, hexadecane, and a hydrocarbon mixture at temperatures of 5 and 15 C. The 10-C decrease in temperature resulted in an average 2.2-fold decrease in generation time of the bacteria. Gas-liquid chromatographic measurements of Venezuelan and Arabian crude oils which had been incubated with the Nocardia sp. showed significant degradation of the n-alkane portion and the chromatographically unresolved components of the oils. The concentration of elemental nitrogen required to bring about the disappearance of 1 mg of hexadecane by the Nocardia sp. was 0.5 mg. The results confirm suggestions that the rate of natural biodegradation of oil in marine temperate-to-polar zones is probably limited by low temperatures and phosphorus concentrations, but suggest that the concentrations of nitrogen occurring naturally are probably not rate-limiting factors.     

Ultrastructural aspects of the cytoplasmic origin and accumulation of oil in olive fruit (Olea europaea)

The development of oil bodies and oil droplets in fruits of olive was examined at the ultrastructural level. Both oil bodies that form in young fruits and oil droplets that develop with fruit maturation are cytoplasmic bodies. The formation of the small oil bodies occurs in localized regions of the cytoplasm. These bodies are closely associated and fuse together, forming a small oil droplet that protruded against and indented the vacuolar membrane. As the fruit matures, new oil bodies appear to form and fuse with the oil droplet, resulting in the formation of a single large oil droplet of about 30 μm in diameter in most mature mesocarp cells. The cytoplasmic region where the oil bodies formed had a granulate, ultrastructural appearance, and cytoplasmic components such as membranes and ribosomes were noticeably absent in these regions. The granulate material coated the oil bodies and oil droplets, and appeared as a thin, compressed band between the round inner surface of the droplets and the indented tonoplast. We suggest that this granulate material is involved in the synthesis of the oil and, with enlargement of the oil bodies, this coat becomes thinner in regions where they are closely associated, resulting in zones where confluence of the oil occurs.     

Investigations on the spontaneous emitted and hydrodistilled volatiles of Platycladus orientalis (L.) Franco grown in four different biogeographic zones of Jordan

The essential oil of the fresh leaves of Platycladus orientalis (L.), grown in four different biogeographic zones of Jordan,- (the Mediterranean, Irano-Turanian, Saharo-Arabian, and Sudanian penetration) -, were obtained by hydrodistillation and analysed by gas chromatography (GC) and gas chromatography-mass-spectrometry (GC/MS). The actual composition of the spontaneous emitted volatiles was obtained using the solid-phase-micro-extraction (SPME) method and investigated using the same chromatographic and spectroscopic methods. Hydrocarbon monoterpenes dominated the hydrodistilled oils and emissions of all regions. Bicyclic monoterpenes (sabinene, α-pinene, and α-thujene) and monocyclic α-terpinene were detected as the major constituents of the oils and emissions. Additionally, hierarchical cluster analysis (HCA) revealed that the clustering is based on the region of collection rather than the applied methodology. Differences were observed in the quantity of the obtained oils (P-values <0.01); the highest amount of volatile oil was obtained from samples grown in the Irano-Turanian biogeographic zone.     

Method for the quantitative study of the growth of fibroblastic cells in tissue culture

The method is elaborated for a quantitative evaluation of hypodermic fibroblast element growth in tissue culture of albino rats. The method is based on determination of the growth activity and intensity for each of the explant growth zones (compact, necwork-like zones and zone of migrating elements). The method permits a rapid and an exact evaluation of the influence of different substances added to the culture medium.     

Assessment of growth zones on whole and thin-sectioned otoliths in <Emphasis Type="Italic">Sperata aor</Emphasis> (Bagridae) inhabiting the River Ganga,India

The present study was undertaken with the objective to assess the clarity of growth zones on whole and thin-sectioned otoliths in Sperata aor. A total of 125 sagittal otoliths of S. aor were collected monthly from the river Ganga during the period, April to December 2013 at Narora, Uttar Pradesh, India. Thin sections (approximately 0.5 mm) of one of the sagittal otoliths of each fish were cut using IsoMet® Low Speed Saw. Both whole otoliths and thin-sectioned otoliths were then examined under stereozoom microscope. Parameters of agreement on growth zones were calculated by comparing the number of growth zones obtained independentlyby the two readers (R1 and R2) from the two methods (whole otolith and thin-sectioned otolith method). Thin-sectioned otolith method exhibited higher agreement than whole otolith method based on linear regression analysis and growth zones bias plot. Between readers, higher agreement was noted for reader 1 than reader 2, plausibly due to his relatively more experience in examining the growth zones on the otoliths. However, both readers reported independently that the growth zones were clearer on thin sections than on whole otoliths especially those from older individuals. Thus, it may be concluded that the thin-sectioned otolith method should be utilized for assessment of growth zones in S. aor populations from the river Ganga.     

Study of the effect of Ammoides pusilla (Brot.) Breist, essential oil against Pseudomonas sp

The economic losses caused by plant pathogens, the development of genetic resistance to applied pesticides by major pathogenic bacteria and public concerns about the use of synthetic chemicals on food and environment, increased interest in the search of alternative safe methods to control diseases spreading. Biological control with plant extracts has emerged as a promising option. The present study was carried out to determine the effect of Ammoides pusilla essential oil on the growth of two pathogenic bacteria, Pseudomonas syringae pv. syringae and Pseudomonas syringae pv. mosprunorum Three essential oil treatments, 1/2 v/v, 1/5 v/v and 1/10 v/v concentrations, were tested onto these bacteria, using the agar diffusion test. The results showed that 1/2 v/v concentration treatment completely inhibited Pseudomonas syringae pv. mosprunorum growth and produced a 35 mm diameter inhibition zone for Pseudomonas syringae pu. syringae. 1/5 v/v essential oil concentration produced inhibition zones of 19 and 17 mm diameter for Pseudomonas syringae pv. syringae and Pseudormonas syringae pv. mosprunorum respetively, while 1/10 v/v essential oil concentration gave inhibition plates of 11 and 12 mm diameter for both stains in the order cited. In in vitro culture essential oil gave promising results suggesting that future studies should be carried out and focus on determining appropriate formulation of this bio-molecule to be use as a bio-control agent.     

Molecular detection of marine bacterial populations on beaches contaminated by the Nakhodka tanker oil-spill accident

In January 1997, the tanker Nakhodka sank in the Japan Sea, and more than 5000 tons of heavy oil leaked. The released oil contaminated more than 500 km of the coastline, and some still remained even by June 1999. To investigate the long-term influence of the Nakhodka oil spill on marine bacterial populations, sea water and residual oil were sampled from the oil-contaminated zones 10, 18, 22 and 29 months after the accident, and the bacterial populations in these samples were analysed by denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S rDNA fragments. The dominant DGGE bands were sequenced, and the sequences were compared with those in DNA sequence libraries. Most of the bacteria in the sea water samples were classified as the  Cytophaga – Flavobacterium – Bacteroides phylum, α- Proteobacteria or cyanobacteria. The bacteria detected in the oil paste samples were different from those detected in the sea water samples; they were types related to hydrocarbon degraders, exemplified by strains closely related to Sphingomonas subarctica and Alcanivorax borkumensis . The sizes of the major bacterial populations in the oil paste samples ranged from 3.4 × 10⁵ to 1.6 × 10⁶ bacteria per gram of oil paste, these low numbers explaining the slow rate of natural attenuation.     

Gas and Liquids in Intercellular Spaces of Maize Roots

Oils are spontaneously absorbed by gas-filled intercellularspaces (IS) in maize root cortex. The network of these spacesin living root sections was imaged by confocal laser scanningmicroscopy using a fluorescent solution of Nile red in oil.The gas volume fraction (GVF) of root segments was quantifiedby the increase in weight (differentiated zones) or tissue density(2–3 mm root tips) due to complete vacuum infiltration.Cooling to 6 °C or inhibition of oxidative phosphorylationdiminished the GVF of root tips but did not significantly affectthe GVF of differentiated root zones. The threshold pressuredifference for measurable infiltration of isolated root segmentsis lower (10 to 15  kPa) than the threshold for infiltrationof comparable zones of attached roots or of detached roots withthe cut surface sealed (>60 kPa). In the absence of an opencut, pressure-driven infiltration of the root cortex is acceleratedby microscopic fissures within the epidermal/hypodermal barrier.The GVF of the root cortex was reduced after transferring rootsfrom sugar solutions (0.1 to 0.3M ) to water. This points toefficient water transport from the medium to sugar-containingcortical cell walls through epidermal and hypodermal protoplasts.When 2-cm-long primary roots were vacuum infiltrated in situand then allowed to grow on aerated mineral medium for a further5 d, cortical IS of the originally infiltrated root bases remainedfilled with liquid but the subsequently grown apical root zoneshad a normal GVF. Copyright 1999 Annals of Botany Company Apoplastic and protoplasmic route, maize, infiltration, intercellular spaces, oil absorption, confocal laser scanning microscope, water transport, Zea mays L.