Life cycle assessment of waste strategies for used lubricating oil

Purpose

The study aimed to evaluate the environmental impacts of used lubricating oil (ULO) recovery in the largest oil consumer country in Africa, Egypt. The main questions were: What are the impacts of the different waste management strategies for the recovery of used lubricating oil and which waste management strategy is more eco-friendly?

Methods

Life cycle assessment (LCA) was employed to model the environmental impacts of the two waste management approaches for used lubricating oil recovery in Egypt: recycling by re-firing and recovery by co-firing. The model was applied to assess the impacts of one of the largest ULO recovery units in the Middle East and North Africa (MENA) region and the only operating unit in Egypt. The following impact categories were included: global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), carcinogens potential (CP), ecotoxicity potential (ETP), respiratory inorganic formation potential (RIFP), respiratory organic formation potential (ROFP), radiation potential (RP), ozone layer depletion (OLD), mineral depletion (MD), land use (LU) and fossil fuel depletion (FFD).

Results and discussion

Results indicated that recycling by re-refining strategy is more environment-friendly. De-asphalting, de-aromatization and de-waxing processes are the main processes that affect the environmental impacts of lubricating oil production in both strategies, due to the use of hazard materials and toxic solvents in these processes. Fuel gas and fuel oil used as a fuel in the refinery and power units are the main contributors affecting the environmental impacts in case of recycling by re-refining strategy. The highest impacts were detected on FFD, followed by RIFP, GWP, AP, EP, ETP and CP in both strategies; no impacts were detected on RP, OLD and MD.

Conclusions

It can be concluded that recycling by re-refining of ULO is the more eco-friendly approach. This strategy is more energy conservative, saves a diminishing fossil fuel resource and reduces burdens on the environment. ULO containing high percentages of additive remnants such as viscosity index improvers and pour point depressants which represents a valuable resource and its proper management should be given the most attention.

     

Feeding fried oil changes antioxidant and fatty acid pattern of rat and affects rat liver mitochondrial respiratory chain components

Fat frying is a popular food preparation method but several components like antioxidant vitamins could be lost due to oxidation and some others with toxic effects could appear. Because of such large consumption of frying oils, the effect of high temperatures on the oils is of major concern both for product quality and nutrition, taking into account that dietary fat source deeply influences several biochemical parameters, especially of mitochondrial membranes. Virgin olive oil possesses specific features for modulating the damages occurred by endogenous and exogenous oxidative stress being particularly rich in antioxidant molecules. We evaluated the extent of modifications suffered by virgin olive oil following a short-time deep fat frying procedure: vitamin E and phenolic compound as well as total antioxidant capacity (measured by ESR) decreased, while polar compounds increased. The intake of such an altered oil mainly affected the hydroperoxide and TBARS contents of mitochondrial membranes which were enhanced after the dietary treatments. Also, several mitochondrial respiratory chain components (Coenzyme Q, cytochrome b, c + c ₁, and a + a ₃) were affected.     

Life cycle assessment of a waste lubricant oil management system

Purpose

This paper compares 16 waste lubricant oil (WLO) systems (15 management alternatives and a system in use in Portugal) using a life cycle assessment (LCA). The alternatives tested use various mild processing techniques and recovery options: recycling during expanded clay production, recycling and electric energy production, re-refining, energy recovery during cement production, and energy recovery during expanded clay production.

Methods

The proposed 15 alternatives and the actual present day situation were analyzed using LCA software UMBERTO 5.5, applied to eight environmental impact categories. The LCA included an expansion system to accommodate co-products.

Results

The results show that mild processing with low liquid gas fuel consumption and re-refining is the best option to manage WLO with regard to abiotic depletion, eutrophication, global warming, and human toxicity environmental impacts. A further environmental option is to treat the WLO using the same mild processing technique, but then send it to expanded clay recycling to be used as a fuel in expanded clay production, as this is the best option regarding freshwater sedimental ecotoxicity, freshwater aquatic ecotoxicity, and acidification.

Conclusions

It is recommended that there is a shift away from recycling and electric energy production. Although sensitivity analysis shows re-refining and energy recovery in expanded clay production are sensitive to unit location and substituted products emission factors, the LCA analysis as a whole shows that both options are good recovery options; re-refining is the preferable option because it is closer to the New Waste Framework Directive waste hierarchy principle.     

Change in fluxes of carbon dioxide,methane and nitrous oxide due to forest drainage of mire sites of different trophy

Northern peatlands accumulate atmospheric CO₂ thus counteracting climate warming. However, CH₄ which is more efficient as a greenhouse gas than CO₂, is produced in the anaerobic decomposition processes in peat. When peatlands are taken for forestry their water table is lowered by ditching. We studied long-term effects of lowered water table on the development of vegetation and the annual emissions of CO₂, CH₄ and N₂O in an ombrotrophic bog and in a minerotrophic fen in Finland. Reclamation of the peat sites for forestry had changed the composition and coverage of the field and ground layer species, and increased highly the growth of tree stand at the drained fen. In general, drainage increased the annual CO₂ emissions but the emissions were also affected by the natural fluctuations of water table. In contrast to CO₂, drainage had decreased the emissions of CH₄, the drained fen even consumed atmospheric CH₄. CO₂ and CH₄ emissions were higher in the virgin fen than in the virgin bog. There were no N₂O emissions from neither type of virgin sites. Drainage had, however, highly increased the N₂O emissions from the fen. The results suggest that post-drainage changes in gas fluxes depend on the trophy of the original mires.     

LCA of soybean meal

Background, Aim and Scope  Soybean meal is an important protein input to the European livestock production, with Argentina being an important supplier. The area cultivated with soybeans is still increasing globally, and so are the number of LCAs where the production of soybean meal forms part of the product chain. In recent years there has been increasing focus on how soybean production affects the environment. The purpose of the study was to estimate the environmental consequences of soybean meal consumption using a consequential LCA approach. The functional unit is ‘one kg of soybean meal produced in Argentina and delivered to Rotterdam Harbor’. Materials and Methods  Soybean meal has the co-product soybean oil. In this study, the consequential LCA method was applied, and co-product allocation was thereby avoided through system expansion. In this context, system expansion implies that the inputs and outputs are entirely ascribed to soybean meal, and the product system is subsequently expanded to include the avoided production of palm oil. Presently, the marginal vegetable oil on the world market is palm oil but, to be prepared for fluctuations in market demands, an alternative product system with rapeseed oil as the marginal vegetable oil has been established. EDIP97 (updated version 2.3) was used for LCIA and the following impact categories were included: Global warming, eutrophication, acidification, ozone depletion and photochemical smog. Results  Two soybean loops were established to demonstrate how an increased demand for soybean meal affects the palm oil and rapeseed oil production, respectively. The characterized results from LCA on soybean meal (with palm oil as marginal oil) were 721 gCO₂ eq. for global warming potential, 0.3 mg CFC11 eq. for ozone depletion potential, 3.1 g SO₂ eq. for acidification potential, −2 g NO₃ eq. for eutrophication potential and 0.4 g ethene eq. for photochemical smog potential per kg soybean meal. The average area per kg soybean meal consumed was 3.6 m²year. Attributional results, calculated by economic and mass allocation, are also presented. Normalised results show that the most dominating impact categories were: global warming, eutrophication and acidification. The ‘hot spot’ in relation to global warming, was ‘soybean cultivation’, dominated by N₂O emissions from degradation of crop residues (e.g., straw) and during biological nitrogen fixation. In relation to eutrophication and acidification, the transport of soybeans by truck is important, and sensitivity analyses showed that the acidification potential is very sensitive to the increased transport distance by truck. Discussion  The potential environmental impacts (except photochemical smog) were lower when using rapeseed oil as the marginal vegetable oil, because the avoided production of rapeseed contributes more negatively compared with the avoided production of palm oil. Identification of the marginal vegetable oil (palm oil or rapeseed oil) turned out to be important for the result, and this shows how crucial it is in consequential LCA to identify the right marginal product system (e.g., marginal vegetable oil). Conclusions  Consequential LCAs were successfully performed on soybean meal and LCA data on soybean meal are now available for consequential (or attributional) LCAs on livestock products. The study clearly shows that consequential LCAs are quite easy to handle, even though it has been necessary to include production of palm oil, rapeseed and spring barley, as these production systems are affected by the soybean oil co-product. Recommendations and Perspectives  We would appreciate it if the International Journal of Life Cycle Assessment had articles on the developments on, for example, marginal protein, marginal vegetable oil, marginal electricity (related to relevant markets), marginal heat, marginal cereals and, likewise, on metals and other basic commodities. This will not only facilitate the work with consequential LCAs, but will also increase the quality of LCAs.     

Assessment of Helicobacter pylori eradication by virgin olive oil

Background: A recent study conducted by Medina et al. disclosed that virgin olive oil has a bactericidal effect in vitro against Helicobacter pylori because of its contents of certain phenolic compounds with dialdehydic structures. We carried out two clinical trials to evaluate the effect of virgin olive oil on H. pylori‐infected individuals. Materials and Methods: Two different pilot studies were performed with 60 H. pylori‐infected adults. In the first study, thirty subjects who tested positive for H. pylori received 30 g of washed virgin olive oil for 14 days, and after 1 month, the patients took 30 g of unwashed virgin olive oil for another 14 days. In a second study, a group of 30 subjects received 30 g of a different virgin olive oil for 14 days. Helicobacter pylori‐infection status was checked by the urea breath test. Results: Helicobacter pylori was eradicated in 8 of 30 individuals when microorganism status was checked after 4–6 weeks from the first clinical intervention although 12 of 30 individuals did not show H. pylori infection at 24–72 hour of the last oil dose. Eradication rates were 27 and 40% by intention to treat and per protocol, respectively. Moreover, only 3 of 30 individuals were H. pylori negative after 4–6 weeks from the second clinical intervention but 5 of 30 were negative at 24–72 hour of the last oil dose. Eradication rates were 10 and 11% by intention to treat and per protocol, respectively. It must also be noted that 13 subjects withdrew from the studies because of taste and nausea drawbacks. Conclusions: The administration of virgin olive oil showed moderate effectiveness in eradicating H. pylori. Further studies are needed to confirm these findings, especially with longer periods, different administration conditions, and several types of olive oils.     

Carbon and Water Footprints and Energy Use of Greenhouse Tomato Production in Northern Italy

This study reports on the carbon, water, and energy footprints of tomatoes grown in a greenhouse in Northern Italy and two possible future variations of heating and carbon dioxide (CO₂) fertilization on the current setup. The heat supply in place, consisting of natural gas (NG) and canola oil combustion, is compared to cogeneration and incineration of municipal solid waste for heating and CO₂ from industrial exhaust for fertilization. As a benchmark, the current system is also compared to a conventional system, in which heat is delivered solely based on NG. Each kilogram (kg) of fresh tomatoes (“Cuore di Bue” variety) produced in the current greenhouse emits 2.28 kg CO₂ equivalents (eq) and uses 95.5 megajoules (MJ) eq energy and 122 liters (L) of water. Relative to the system in place, the carbon footprint (CF) is 57.5% and 18% higher with conventional NG heating and cogeneration and is 40% lower with waste valorization. Further, 33%, 55%, and 63% less energy and 9%, 96%, and 14% less water are used in the conventional, cogeneration, and waste valorization scenarios, respectively. This confirms that there are multiple strategies to reduce the impact of the tomato production under consideration.     

Biodegradation of slop oil from a petrochemical industry and bioreclamation of slop oil contaminated soil

Slop oil, i.e. waste oil from a petrochemical complex, contains at least 240 hydrocarbon components, of which 54% are from C₅ to C₁₁ and the rest from C₁₂ to C₂₃. Of 22 isolated bacterial cultures that were able to degrade slop oil, seven could each degrade about 40% of the slop oil, and a mixture of all seven could degrade 50% in liquid medium. Bioaugmentation of soil contaminated with slop oil with the mixed bacterial culture gave up to 70% degradation of slop oil after 30 days. This compares with 40% degradation without bioaugmentation. Bioaugmentation led to a significant increase in counts of bacteria able to degrade slop oil. Wheat sown on bioaugmented soil germinated and grew better than on non-augmented soil and led to increased degradation of slop oil (up to 80%). This indicates the potential of mixed culture for bioremediation.     

Biodegradation of a dilute waste oil emulsion applied to soil

Summary The use of land treatment for disposal of a dilute waste oil emulsion generated by an aluminum rolling industry was investigated. Major components of the waste, identified by gas chromatography and mass spectrometry, were linear and branched (C₁₂–C₂₅) and fatty acid emulsifiers (primarily, isomers of oleic acid). Hexadecane and pristane were readily biodegraded in vitro when added to soil collected from the waste disposal site. Hydrocarbons and fatty acids extracted from the waste were similarly, biodegraded, however, the rate of decomposition may have depended on the history of waste applications to soil collected from the land treatment site. The apparent half-life of resolvable waste hydrocarbons and fatty acids was 9.5 days in soil which had received waste applications averaging 25.4l m^–2 wk^–1. In contrast, soil receiving either 50.8l m^–2 wk^–1 or no waste application during summer 1987 apparent exhibited half-lives of 28.1 and 60.3 days, respectively. Waste components were restricted to the upper 48 cm of the soil cores collected from the disposal site. Core samples also provided evidence for biodegradation of hydrocarbons and fatty acids as well as an accumulation of other compounds not readily resolvable by gas chromatographyPublished with the approval of the Director of the West Virginia University Agriculture and Forestry Experiment Station as Scientific Article # 2122.     

Pistacia lentiscus fruit oil reduces oxidative stress in human skin explants caused by hydrogen peroxide

We investigated the efficacy of Pistacia lentiscus fruit oil (PLFO) for protecting human skin from damage due to oxidative stress. PLFO contains natural antioxidants including polyphenols, sterols and tocopherols. We compared the antioxidant potential of PLFO with extra virgin olive oil (EVOO). Explants of healthy adult human skin were grown in culture with either PLFO or EVOO before adding hydrogen peroxide (H₂O₂). We also used cultured skin explants to investigate the effects of PLFO on lipid oxidation and depletion of endogenous antioxidant defense enzymes including glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) one day after 2 h exposure to H₂O₂. We found that PLFO scavenged radicals and protected skin against oxidative injury. PLFO exhibited greater antioxidant and free radical scavenging activity than EVOO. Skin explants treated with PLFO inhibited H₂O₂ induced MDA formation by inhibition of lipid oxidation. In addition, the oil inhibited H₂O₂ induced depletion of antioxidant defense enzymes including GPx, SOD and CAT. We found that treatment with PLFO repaired skin damage owing to its antioxidant properties.     

Removal of emulsified food and mineral oils from wastewater using surfactant modified barley straw

Barley straw, an agricultural waste, was chemically modified and evaluated for the removal of emulsified oils from aqueous solution. The chemical modification was performed using NaOH and a cationic surfactant, hexadecylpyridinium chloride monohydrate (CPC). The surface textural and chemical properties of the surfactant modified barley straw (BMBS) were characterized by N₂ adsorption, FT-IR, SEM and water soluble mineral content. The adsorption tests were carried out in batch adsorption system for removal of standard mineral oil (SMO) and canola oil (CO) from water. For both emulsified oils in wastewater, adsorption was found to be strongly related with solution pH. The isotherm study indicated that emulsified oil adsorption on BMBS could be fitted well with the Langmuir model other than Freundlich model. The maximum adsorption capacity for CO and SMO at 25 °C determined from the Langmuir isotherm is 613.3 and 584.2 mg g⁻¹, respectively. Desorption tests in water solution show that oil is strongly bonded with adsorbent and desorption is only about 1–2% in 24 h.     

Optimization of novel halophilic lipase production by Fusarium solani strain NFCCL 4084 using palm oil mill effluent

Among different sources of lipases, fungal lipases have continued to attract a wide range of applications. Further, halophilic lipases are highly desirable for biodiesel production due to the need to mitigate environmental pollution caused as result of extensive use of fossil fuels. However, currently, the high production cost limits the industrial application of lipases. In order to address this issue, we have attempted to optimize lipase production by Fusarium solani NFCCL 4084 and using palm oil mill effluent (POME) based medium. The production was optimized using a combinatory approach of Plackett-Burman (PB) design, one factor at a time (OFAT) design and face centred central composite design (FCCCD). The variables (malt extract, (NH₄)₂SO₄, CaCl₂, MgSO₄, olive oil, peptone, K₂HPO₄, NaNO₃, Tween-80, POME and pH) were analyzed using PB design and the variables with positive contrast coefficient were found to be K₂HPO₄, NaNO₃, Tween-80, POME and pH. The significant variables selected were further analyzed for possible optimum range by using OFAT approach and the findings revealed that K₂HPO₄, NaNO₃, and Tween-80 as the most significant medium components, and thus were further optimized by using FCCCD. The optimum medium yielded a lipase with an activity of 7.8 U/ml, a significant 3.2-fold increase compared to un-optimized medium. The present findings revealed that POME is an alternative and suitable substrate for halophilic lipase production at low cost. Also, it is clearly evident that the combinatory approach employed here proved to be very effective in producing high activity halophilic lipases, in general.     

Genetic Analysis of Oil Content in Brassica napus L. Using Mixed Model of Major Gene and Polygene

The joint segregation analysis of a mixed genetic model of major gene plus poly-gene was conducted to study the inheritance of oil content in Brassica napus L. Five populations, i.e the populations of 2 parents(P₁ and P₂), F₁, F₂ and F_2:3 (derived from F₂) family, from each of the two crosses (1141B × Ken C₁-1, 32B × Ken C₁-2) were investigated. The frequency distributions of oil content in F₂ and F_2:3 family populations show characteristics of a mixed normal distribution, which indicated that the inheritance of oil content followed a major gene plus poly-gene model. Twenty-one genetic models were established, which could be classified into five types: one and two major genes, polygenes, one and two major genes plus polygenes. The most suitable genetic model could be selected using Akaike's Information Criterion and the fitness of the selected one could be examined by a set of tests. Results show that genetic model D-2 is the most fitting genetic model for the trait. In other words, oil content in oilseed rape is controlled by one additive major gene plus additive and dominance polygenes. For cross 1 (1141B × Ken C₁-1) the heritabilities of major gene and poly-genes in F₂ are 68.21% and 27.17%, respectively, and in F_2:3 are 81.70% and 16.80%, respectively. The additive effect of major gene is-1.74, which indicates that the locus of the allele in parent 1141B may decrease the oil content, but that in parent Ken C₁-1 may increase it. The additive and dominance effects of the polygenes are 1.20 and -1.93, respectively. For cross 2 (32B × Ken C₁-2) the heritabilities of major gene and polygenes in F₂ are 66.20% and 28.10%, respectively, and in F_2:3 were 81.00% and 14.90%, respectively. The additive effect of major gene was -3.74, which also indicates that the locus of the allele in parent 32B may decrease the oil content, but that in parent Ken C₁-2 may increase it. The additive and dominance effects are -1.99 and 0.93, respectively. The heritability of the major gene in F_2:3 is higher than that in F₂ in both crosses, so it would be more efficent to conduct selection in F_2:3 families for high oil content in breeding.     

Synthesis of fatty acid methyl ester from used vegetable cooking oil by solid reusable Mg 1-x Zn 1+x O2 catalyst

Fatty acid methyl ester was produced from used vegetable cooking oil using Mg_1−x Zn_1+xO₂ solid catalyst and the performance monitored in terms of ester content obtained. Used vegetable cooking oil was employed to reduce operation cost of biodiesel. The significant operating parameters which affect the overall yield of the process were studied. The highest ester content, 80%, was achieved with the catalyst during 4 h 15 min reaction at 188 °C with methanol to oil ratio of 9:1 and catalyst loading of 2.55 wt% oil. Also, transesterification of virgin oil gave higher yield with the heterogeneous catalyst and showed high selectivity towards ester production. The used vegetable cooking oil did not require any rigorous pretreatment. Catalyst stability was examined and there was no leaching of the active components, and its performance was as good at the fourth as at the first cycle.     

Effect of dietary coenzyme Q and fatty acids on the antioxidant status of rat tissues

Summary.  Wistar rats were fed with different diets with or without supplement coenzyme Q₁₀ (CoQ₁₀) and with oil of different sources (sunflower or virgin olive oil) for six or twelve months. Ubiquinone contents (CoQ₉ and CoQ₁₀) were quantified in homogenates of livers and brains from rats fed with the four diets. In the brain, younger rats showed a 3-fold higher amount of ubiquinone than older ones for all diets. In the liver, however, CoQ₁₀ supplementation increased the amount of CoQ₉ and CoQ₁₀ in both total homogenates and plasma membranes. Rats fed with sunflower oil as fat source showed higher amounts of ubiquinone content than those fed with olive oil, in total liver homogenates, but the total ubiquinone content in plasma membranes was similar with both fat sources. Older rats showed a higher amount of ubiquinone after diets supplemented with CoQ₁₀. Two ubiquinone-dependent antioxidant enzyme activities were measured. NADH-ferricyanide reductase activity in hepatocyte plasma membranes was unaltered by ubiquinone accumulation, but this activity increased slightly with age. Both cytosolic and membrane-bound dicumarol-sensitive NAD(P)H:(quinone acceptor) oxidoreductase (DT-diaphorase, EC 1.6.99.2) activities were decreased by diets supplemented with CoQ₁₀. Animals fed with olive oil presented lower DT-diaphorase activity than those fed with sunflower oil, suggesting that the CoQ₁₀ antioxidant protection is strengthened by olive oil as fat source. Received May 22, 2002; accepted September 20, 2002; published online May 21, 2003 RID="*" ID="*" Correspondence and reprints: Departamento de Biología Celular, Fisiología e Inmunología, Universidad de Córdoba Edificio Severo Ochoa, Campus de Rabanales, 14071 Córdoba, Spain.     

New C9-polyacetylenes from the essential oil of the highly endangered species Baccharis palustris Heering (Asteraceae)

The essential oil composition of the aerial parts from Baccharis palustris Heering (Asteraceae), a highly endangered species, was analyzed by GC/qMS, GC/HRMS-TOF, FT-IR, UV–vis and NMR spectroscopy using 1D and 2D techniques. To our knowledge, this is the first report on the essential oil composition of B. palustris, as well as the first phytochemical study on this plant species. The volatile extracts were obtained from different phenologicals stages of plant, at flowering stage (FS) and vegetative stage (VS), where 51 components were identified accounting for 96.3 % and 99.0 % of the oil, respectively. The oil was rich in polyacetylene compounds (> 75 %), being the main components identified the new natural C₉-polyacetylenes 1-nonene-3,5-diyne (1, here named as baccharisdiyne) (52.7–65.0 %), 1,7(Z)-nonadiene-3,5-diyne [2, 7(Z)-dehydro-baccharisdiyne] (14.4–17.8 %), and 1,7(E)-nonadiene-3,5-diyne [3, 7(E)-dehydro-baccharisdiyne] (1.5–2.4 %). In addition, the known polyacetylenic compounds (Z)-lachnophyllum acid methyl ester (4) (4.3–5.3 %) and (E)-lachnophyllum acid methyl ester (5) (0.2 %) were also identified. Moreover, GC/qMS analysis allowed the identification of other 46 components in the essential oil samples, mainly mono- and sesquiterpenoids. In B. palustris, C₉-polyacetylenes probably derive biogenetically from a C₁₀ precursor: baccharisdiyne (1) would be derived from either or both lachnophyllum methyl ester geometric isomers (4 or 5), by enzymatic hydrolysis followed by decarboxylation. Dehydro-baccharisdiynes (2 and 3) could be produced by a similar pathway starting from the corresponding matricaria acid methyl ester isomers, one of which was tentatively identified at trace-level in B. palustris essential oil.     

Effect of keratinous waste addition on improvement of crude oil hydrocarbon removal by a hydrocarbon-degrading and keratinolytic mixed culture

The aim of this work was to evaluate the effect of keratinous waste addition on oil-hydrocarbon removal, through a mixed culture of oil-degrading bacteria, with the ability to secrete keratinases. The mixed culture was grown in the media with oil, or oil supplemented with chicken-feathers as the keratinous waste. Residual oil-hydrocarbons were determined as total petroleum hydrocarbons (TPHs) and oil fractions and then quantified by GC–FID and GC–MS.Results showed that in presence of the keratinous waste, the removal of oil-hydrocarbons was 57,400 mg l^?1, meanwhile the treatment without waste presented an oil-hydrocarbons removal of 35,600 mg l^?1. The aliphatic fraction was the most removed in both treatments. In addition, chromatographic profiles indicated that the aliphatic fraction showed different degradation pattern; in the presence of keratinous wastes, the C₁₈ to C₂₈ compounds were preferably removed over the C₁₀ to C₁₇. The addition of keratinous waste not only improved the oil-hydrocarbons removal but, it changed the removal pattern of the target hydrocarbons.     

Dietary n-3 fatty acids,curcumin and capsaicin lower the release of lysosomal enzymes and eicosanoids in rat peritoneal macrophages

Male Wistar rats (12 rats/group) were fed a diet containing 8 wt % coconut oil or groundnut oil or cod-liver oil for a total period of 8 weeks. The diets were also supplemented with 2 wt % groundnut oil for providing essential fatty acids. During the last 2 weeks, 6 rats form each group were additionally given curcumin (30 mg/kg body wt/day) or capsaicin (5 mg/kg body wt/day) in 1 ml groundnut oil. The peritoneal macrophages from rats fed cod-liver oil diet secreted lower levels of lysosomal enzymes collagenase, elastase and hyaluronidase as compared to those from rats fed coconut oil or groundnut oil diets. Curcumin and capsaicin significantly lowered the secretion of these lysosomal enzymes from macrophages in animals given coconut oil or groundnut oil diet. Macrophages from rats fed cod-liver oil secreted lower amounts of prostaglandin E₂, 6-keto PGF_1a, leukotrienes B₄and C₄and also incorporated lesser amounts of [^3H]-arachidonic acid as compared to those given coconut oil or groundnut oil diets. Curcumin and capsaicin lowered the secretion of these eicosanoids and decreased the incorporation of [³H]-arachidonic acid in macrophage lipids. However curcumin and capsaicin significantly increased the secretion of 6-keto PGF_1ain all the groups of animals. These studies indicated that dietary cod-liver oil (rich in n-3 fatty acids), and spice principles curcumin and capsaicin can lower the secretory functions of macrophages in a beneficial manner.     

驯化复合微生物菌群处理废弃钻井泥浆活性研究

【背景】油田废弃钻井泥浆含油量高,污染物复杂,环境危害严重,现有技术无法满足日益发展的石油开采行业在废弃钻井泥浆处理方面的需求。生物法处理废弃钻井泥浆,工艺简单,成本低,但也存在局限,包括广谱性差、处理周期长、原油降解率低、泥浆性质波动冲击工艺稳定性等。【目的】构建一种高活性和高环境耐受能力的微生物菌群,分析遗传稳定性和综合性能,提高废弃钻井泥浆处理技术水平。【方法】通过定向富集、诱导驯化的方法,提高活性群落对石油烃乳化降解效率,降低共代谢底物反馈抑制和群体感应系统敏感度,分析群落结构和活性成员的种群类别,分析乳化降解石油烃的活性对应关系。【结果】从含油量超过12g/kg、芳烃-胶质沥青含量超过80%、含盐量超过8g/kg的钻井废弃泥浆中富集得到1个活性微生物菌群,主要成员包括假单胞菌属(Pseudomonas)、根瘤菌属(Rhizobium)、红细菌属(Rhodobacter)和嗜碱还原硫素杆菌(Dethiobacter alkaliphilus),比例分别达27.44%、20.73%、8.54%和7.93%。在超过22代的连续驯化过程中,假单胞菌(Pseudomonas)、类希瓦氏菌(Alishewanella)和盐单胞菌(Halomonas)数量达92.72%,菌群结构和活性趋于稳定。处理钻井废弃泥浆5 d,土壤含油率由处理前的12403 mg/kg降低到处理后的42 mg/kg,综合脱油效率99.67%,石油烃降解率68.9%。分析微生物群落作用前后石油饱和土壤中的石油含量变化,原始含油量261 g/kg,处理后含油量305 mg/kg,脱油率99.88%。【结论】菌群驯化后活性稳定,耐受高盐环境能力强,在钻井废弃泥浆、含油土壤及油泥污染物处理方面具有很强的工业应用潜力。