Simple,Rapid Lipidomic Analysis of Triacylglycerols in Bovine Milk by Infusion-Electrospray Mass Spectrometry

Bovine milk is a complex mixture of lipids, proteins, carbohydrates, and other factors of which lipids comprise 3–5% of the total mass. Rapid analysis and characterization of the triacylglycerols (TAG) that comprise about 95% of the total lipid is daunting given the numerous TAG species. In the attached methods paper, we demonstrate an improved method for identifying and quantifying TAG species by infusion-based “shotgun” lipidomics. Because of the broad range of TAG species in milk, a single internal standard was insufficient for the analysis and required sectioning the spectrum into three portions based upon mass range to provide accurate quantitation of TAG species. Isobaric phospholipid interferences were removed using a simple dispersive solid-phase extraction step. Using this method, > 100 TAG species were quantitated by acyl carbon number and desaturation level in a sample of commercially purchased bovine milk.     

Lipid analysis of Greek broad bean oil: Preparation of liposomes and physicochemical characterization

Liposomes were prepared from the isolated phospholipids of mature broad bean [Vicia faba L. (syn. Fabae calabaricae)] oil and their physical properties were studied. The method of preparation was the hydration of the thin lipid film, while the probe sonication methodology was used for reducing the size of the vesicles. The seeds of the broad bean were collected in two different periods of maturity and extracted by the Bligh‐Dyer method, and the lipid classes were studied by HPTLC/FID. The oils were found to be rich in polar lipids (63.1% and 60.2% of total lipids) and low in neutral lipids (36.9% and 39.8% of total lipids) for the immature and mature seed oils, respectively. The neutral lipid fraction consisted mainly of triacylglycerides (34.2% and 32.3%) whereas the polar lipids mainly consisted of phospholipids (60.2% and 54.2%) for the mature and immature seed oils, respectively. Sphingolipids (8.9%) were identified only in the immature seed oil. The overall goal of this study was the preparation of a new liposomal formulation with physicochemical properties such as unique lipid composition, size and ζ‐potential, which are important factors influencing drug delivery to the target tissues.     

Mineralization of Ibuprofen and Humic Acid through Catalytic Ozonation

Advanced oxidation methods are used to remove traces of pharmaceuticals from aquatic environments. The application of a catalyst improves the total organic carbon removal during ozonation of pharmaceuticals in water. The aim of this study was to use MnO₂-CuO/ γ-Al₂O₃ catalyst for ozonation of ibuprofen (5 mgL^?1) and evaluate the effect of the presence of humic acid in the removal process. The presence of the catalyst increased the mineralization percentage of ibuprofen from 27% for noncatalytic ozonation to 55% in the presence of catalyst. The presence of humic acid increased noncatalytic mineralization by 10%. The reusability and stability of the catalyst, and its ability to adsorb reaction by-products were demonstrated.     

Degradation and Transformation of Organic Compounds in Songhua River Water by Catalytic Ozonation in the Presence of TiO2/Zeolite

This paper presents experimental results of the catalytic ozonation of Songhua River water in the presence of nano-TiO₂ supported on Zeolite. The removal efficiency of TOC and UV₂₅₄, the variation of AOC and molecular weight distribution of organics was studied. Results showed that TOC and UV₂₅₄ removal efficiency by ozone was improved in the presence of TiO₂/Zeolite, and increased by 20% and 25%, respectively. The part of organic compounds less than 1000 Da increased in ozonation, but decreased in catalytic ozonation. The AOC of water increased in catalytic ozonation, and the increase of AOC was particularly obvious when ozone dose increased from 28.8 mg·L^?1 to 46.6 mg·L^?1. The degradation and transformation of organic compounds was analyzed by means of GC-MS. The total number of organic compounds was reduced from 50 in the untreated water to 36 and 20, respectively, in ozonation and catalytic ozonation. The removal efficiency of the total organic compounds peak area in ozonation and catalytic ozonation were 23.5% and 62.5%, respectively. Most of the hydrocarbons could be removed easily in ozonation and catalytic ozonation. The organic compounds having hydroxyl, carboxyl or carbonyl groups were hard to be removed in ozonation, but could be removed efficiently in the presence of TiO₂/Zeolite.     

Optimization of an Analytical Procedure for Extraction of Lipids from Microalgae

An optimized procedure for extraction of total and non-polar lipids from microalgae is proposed. The effects of solvent, pretreatment (lyophilization, inactivation of lipases, and addition of antioxidants) and cell-disruption (liquid nitrogen, sonication, and bead beating) on total lipid content, lipid class, and fatty acid composition were examined. Chloroform–methanol 1:1 was shown to be the best solvent mixture for extraction of total lipids from microalgae. When performing this extraction, lyophilized algae can be used, no pretreatment with isopropanol to inactivate the lipases is needed and addition of antioxidants is not necessary. Furthermore, cell-disruption is not essential, although in that case two extractions must be performed in series to ensure that, irrespective of the microalgal species, all lipids are extracted. Determination of non-polar lipid content should be performed by separation of the total lipid extract on an SPE column. Extraction using petroleum ether is only appropriate when a bead beater is used for pretreatment.     

Fatty acids of lipid fractions in extracellular polymeric substances of activated sludge flocs

Phospholipid (PL), glycolipid (GL), and neutral lipid (NL) FA, and the lipopolysaccharide 2- and 3-hydroxy (LPS 2-OH and 3-OH) FA of activated sludges and extracted extracellular polymeric substances (EPS) were determined on samples collected from two wastewater treatment plants. EPS extracted from sludges by means of sonication and cation exchange contained proteins (43.4%), humic-like substances (11.5%), nucleic acids (10.9%), carbohydrates (9.9%), and lipid-bound FA (1.8%). The lipids associated with EPS were composed of GL, PL, NL, and LPS acids in proportions of 61, 21, 16, and 2%, respectively. The profiles of lipid-bound FA in activated sludges and EPS were similar (around 85 separate FA were identified). The FA signatures observed can be attributed to the likely presence of yeasts, fungi, sulfate-reducing bacteria, gram-positive and gram-negative bacteria, and, in lesser quantities, mycobacteria. Comparison of data from the dates of sampling (January and September) showed that there were more unsaturated PLFA in the EPS extracted from the activated sludges sampled in January. This observation could be partly related to microorganism adaptation to temperature variations. The comparison between two wastewater treatment plants showed that the FA profiles were similar, although differences in microbial community structure were also seen. Most of the FA in sludges had an even number of carbons.     

ACF催化臭氧化降解苯酚的反应参数影响

研究了活性碳纤维(ACF)催化臭氧化降解苯酚过程中各种参数的影响。结果表明,ACF能够显著提高臭氧化效率,当ACF为1g,反应10min时苯酚的去除率为96.8%,而同样条件下活性炭仅为68%;臭氧化效率在酸性下几乎相同并高于碱性下,而且在碱性下随pH值升高而降低;臭氧化空气流量从0.04m3/h增加到0.16m3/h,反应10min时的效率提高为17%;苯酚初始浓度升高到500mg/L仅使臭氧化效率下降不到10%。重复实验表明臭氧化过程中ACF的催化性能可以得到原位再生。     

Residual Sugars in Klason Lignin

The Klason method–dissolution of carbohydrates in sulfuric acid–has been widely used for the determination of lignin content in woody materials. It was an unsolved problem, however, whether Klason lignin still contains carbohydrates. We observed previously that Klason lignin becomes almost completely soluble in water after ozone treatment. In this work, the residual sugar content of Klason lignin was determined on the basis of the above observation.

Water-soluble lignin was prepared by ozone treatment (25 and 45 min) of finely-crushed Klason lignin obtained from spruce and birch wood meals. After hydrolysis with 2N-trifluoroacetic acid followed by sodium borohydride reduction, residual sugars were determined by GLC as their alditol acetates.

Klason lignin ozonated for 25 min contained 0.75% and 0.95% neutral sugars for spruce and birch, respectively. Most of the residual sugars were derived from hemicelluloses. Because ozone degrades carbohydrates, the prolonged ozonation was found to decrease the content of residual sugars. Therefore, the values obtained here are the minimum ones for the residual sugar content in Klason lignin.     

Ultraschall-Extraktion vegetabiler Feststoffe — Untersuchungen zur Lipidfreisetzung aus Rapssaat

Ultrasonic-Extraction of Vegetable Materials — Investigation of Lipid Release from Rapeseed The effect of ultrasonics on the hexane-extraction of rapeseed-elements (dehulled meat and hulls) was investigated. The experiments were carried out in an immersion extractor coupled with an ultrasonic transducer, different ultrasonic energy levels (max. 100 W, calibrated calorimetrically; 20 kHz) were applied independently to structurally unaltered rapeseed material of various water-content. The timespan required for 50%-release of hexane-soluble lipids was reduced by a factor of 3 for rapeseed meat and by a factor of 20 in the case of rapeseed hulls, compared with control experiments in a well-stirred extractor without ultrasonics. A marked increase in fines with the duration of sonication was also observed. Several models based on the known relevant phenomena of cavitation and acoustic streaming were proposed. The experimental results, particularly the material destruction and lipidrelease, could be interpreted by taking pseudo-cavitation — due to trapped air bubbles in the intercellular interstices of the meat and in the cavities of the hull testa — into consideration. The effect of sonication can be seen technically as an extractor-internal material disruption. Practical applications of ultrasonic-extraction are at present limited to materials which resist milling and flaking; a case in point is that of the rapeseed hulls.     

Nanofiltration and ozonation for decolorisation and salt recovery from reactive dyebath

Three commercially available high exhaust dyes were used to prepare dyebaths of different shades and subjected to nanofiltration and ozonation. Colour removal, chemical oxygen demand reduction, permeate flux, ozone consumption and total organic carbon removal were analysed to determine the efficiency of nanofiltration and ozonation. It was found that both nanofiltration and ozonation showed a high degree of (>90%) decolorising efficiency. High total organic carbon removal (80%) could be achieved by nanofiltration while ozonation could achieve only a maximum of 55% total organic carbon removal. The treated dyebath was reused for dyeing the fabric and the fabric quality was compared for the different shades. It was found that the quality of the dyed fabric was good for all shades dyed with nanofiltration permeate. The quality of the dyed fabric was affected for dark shades dyed with the ozone decolorised dyebath.     

Total and polar lipids in soybean protein meals

Soybean protein meals obtained by various oil extraction methods have different neutral oil content, and they may contain differnet amounts of polar lipids. Three soy protein meals obtained by different processing methods were extracted by two solvents consecutively, chloroform/methanol (2:1, vol/vol) and water-saturated butanol, for total lipid analysis. The organic flour (i.e., ground soybean) containted 15.52% total lipids; the high protein dispersibility index flour from extrusion-expelling processing and the white flour from conventional solvent extraction contained 11.20 and 1.84% total lipids, respectively. Organic flour contained more polar lipids than the other two protein meals on a dry-weight meal basis. Chloroform/methanol extracted most of the lipid from the meals, whereas water-saturated butanol resulted in an extract with more polar lipids than that from chloroform/methanol extraction.     

Treatment of Industrial Landfill Leachates By Chemical And Biological Methods: Ozonation,Ozonation + Hydrogen Peroxide,Hydrogen Peroxide And Biological Post-Treatment For Ozonated Water

The objective of this study was to determine a suitable treatment method for variable waters from a forest industry landfill site. The main target was to find out the impact of different chemical treatments on the composition and biodegradability of those waters. Earlier studies have shown that biological treatment alone is not a suitable treatment method for these waters. That is why ozonation, ozonation+hydrogen peroxide and hydrogen peroxide treatment were studied in a laboratory scale. The ozonated waters were also biologically post-treated.

All the methods studied were able to degrade a part of the organic compounds and convert them into a more biodegradable form. Also the BOD/COD -ratio increased significantly. The removal of organic compounds by ozonation was 30 - 50 %. Hydrogen peroxide addition did not improve the degradation. The combination of pre-ozonation and biological post-treatment gave a total TOC removal between 50 - 95 %.     

Successful Colonization of Lodgepole Pine Trees by Mountain Pine Beetle Increased Monoterpene Production and Exhausted Carbohydrate Reserves

Lodgepole pine (Pinus contorta) forests have experienced severe mortality from mountain pine beetle (MPB) (Dendroctonus ponderosae Hopkins) in western North America for the last several years. Although the mechanisms by which beetles kill host trees are unclear, they are likely linked to pine defense monoterpenes that are synthesized from carbohydrate reserves. However, how carbohydrates and monoterpenes interact in response to MPB colonization is unknown. Understanding this relationship could help to elucidate how pines succumb to bark beetle attack. We compared concentrations of individual and total monoterpenes and carbohydrates in the phloem of healthy pine trees with those naturally colonized by MPB. Trees attacked by MPB had nearly 300% more monoterpenes and 40% less carbohydrates. Total monoterpene concentrations were most strongly associated with the concentration of sugars in the phloem. These results suggest that bark beetle colonization likely depletes carbohydrate reserves by increasing the production of carbon-rich monoterpenes, and other carbon-based secondary compounds. Bark beetle attacks also reduce water transport causing the disruption of carbon transport between tree foliage and roots, which restricts carbon assimilation. Reduction in carbohydrate reserves likely contributes to tree mortality.     

Availability of lysophosphatidylcholine in single bilayer vesicles for hydrolysis by lysophospholipase

Single bilayer vesicles were prepared from total rat liver microsomal lipids to which 5 mol% lysophosphatidylcholine had been added. The availability of lysophosphatidylcholine for enzymatic hydrolysis by lysophospholipase (EC 3.1.1.5) was found to be higher in vesicles prepared by the cholate dispersion technique when compared with sonicated vesicles. Sepharose 4 B chromatography showed that the vesicles prepared by the cholate technique were smaller than those prepared by sonication. This is in contrast to previous observations for egg phosphatidylcholine vesicles. Total rat liver microsomal extracts were found to contain proteolipid, which could be removed by ether precipitation. Cholate vesicles prepared from proteolipid-free extracts were still smaller than sonicated vesicles from this extract. Experiments with [¹⁴C] dextran entrapped in the vesicles indicate that there is no loss of the permeability barrier of the vesicles for high molecular weight solutes during vesicle treatment with lysophospholipase. The high availability of lysophosphatidylcholine in cholate vesicles of total rat liver microsomal lipids is discussed in terms of a highly asymmetric distribution of lysophosphatidylcholine over the inner and outer monolayer of the bilayer.     

Combination of Ozonation and the Fenton Processes for Landfill Leachate Treatment: Evaluation of Treatment Efficiency

Single processes such as ozonation, ozone/hydrogen peroxide, Fenton and several combined treatment schemes were applied for leachate collected from a waste disposal site. The implementation of combined Fenton and ozonation processes resulted in the highest chemical oxygen demand removal (77% from initial value) among all the treatment methods applied, while biodegradability improvement was observed during the Fenton pre-treatment only. Some decrease of chemical oxygen demand was obtained during the single ozonation or combined schemes including ozone resulting in slight if any biodegradability improvement. The addition of hydrogen peroxide to ozonation did not enhance chemical oxygen demand, dissolved organic carbon or biochemical oxygen demand removal compared to ozone alone. Ferric chloride coagulation used as a pre-treatment stage did not improve subsequent chemical oxygen demand removal by ozonation or the Fenton processes. Taking into account the effective chemical oxygen demand, dissolved organic carbon removal and biodegradability improvement the single Fenton process seems to be a preferable treatment method for the leachate treatment. Some reduction in toxicity to Daphnia magna was observed after the application of the studied treatment methods.     

Performance evaluation of pretreatment processes in integrated membrane system for wastewater reuse

A series of lab-scale filtration experiments were performed under various operating conditions to investigate the fouling behavior of microfiltration (MF) membranes when employing two different pretreatment methods. The secondary effluents from a biologically advanced treatment process were fed to each hybrid system, consisting of coagulation-flocculation-MF (CF-MF) and ozonation-MF processes. All experiments were carried out using a stirred-cell system, which consisted of polyvinylidene difluoride (PVDF) MF membranes with a 0.22 μm pore size. When MF membrane was used alone without any pretreatment, the permeate flux dropped significantly. However, in the case of employing polyaluminium chloride (PACl) coagulation and ozonation as a pretreatment, the extent of flux decline rates was enhanced up to 88 and 38%, respectively. In the CF-MF hybrid system, the removal efficiencies of COD and total phosphorus were significantly enhanced at a coagulant dose above 30 mg/L. With ozonation, more than 90% of the color was removed even at a low dosage of ozone (5 mg/L). Therefore, ozonation would be strongly recommended as a pretreatment in terms of removing organic matter. The permeate water quality by ozonation-MF process was in good compliance with the guidelines for wastewater reuse proposed by South Korean Ministry of Environment.     

协同催化臭氧化工艺对水中微量有机污染物的降解

选用城市二级出水作为试验原水,通过静态试验考察了O3、O3/C、O3/UV、O3/UV/C对水中难以生化降解的微量有机物的处理效果。结果表明：波长为254 nm的紫外线和活性炭对水中微量有机物的臭氧化过程具有协同催化作用,并可大幅度提高对臭氧的利用率;在紫外线和活性炭的协同催化臭氧化作用下,对水在254nm处紫外吸光度（E254）的去除率达到87.40%,水中CODCr的去除率可达到59.79%,臭氧的利用率可提高到91.4%。通过考察叔丁醇和碳酸氢钠两种自由基捕捉剂对O3/UV/C反应器处理效果的影响,表明在紫外线和活性炭的协同催化臭氧化作用下,水中有机污染物的氧化降解是多种自由基反应的结果,其中以羟基氧化反应为主。     

Comparative evaluation of solvent extraction methods for the determination of neutral and polar lipids in beef

Samples of lean (< 5% fat), medium (13–15%) and high-fat (> 20%) ground beef were extracted for total lipid by 4 methods of wet extraction employing chloroform/methanol (CM), n-hexane/iso-propanol (HIP) and ethyl alcohol/ethyl ether (AE), and by 3 methods of soxhlet extraction of freeze-dried material by petroleum ether (PE) or eithyl ether (EE), CM and methylene chloride/ methanol (MM). The purified lipid was fractionated into neutral and polar lipid fractions by silicic acid chromatography and the frac-tions were analyzed for fatty acid distribution by gas liquid chroma-tography (GLC). The soxhlet procedure employing either PE or EE extracted less than 75% of total lipid, 89% of triglycérides and 15% of polar lipids from lean beef as compared to other methods, and as the fat content increased from 3 to 20%, extracted amounts of polar lipid which increased to 40% of that extracted by other methods. The fatty acid distribution of the fractionated triglycerides and polar lipids was generally within experimental error for each frac-tion, irrespective of the method of extraction. The percentages of 16:0 and 18:1 were significantly less in polar lipids than in trigly-cerides. In addition to significantly higher percentage of 18:2, the polar lipids contained up to 20% of long-chain fatty acids not detected in triglycerides. The soxhlet procedures with CM or MM were as effective as wet extraction procedures in extracting neutral and polar lipids. Presented at the 73rd AOCS annual meeting, Toronto, 1982. Contribution No. 512, Food Research Institute, Agriculture Canada.     

Disinfection of recycled red‐meat‐processing wastewater by ozone

Ozonation of a real red‐meat‐processing wastewater was conducted in a semi‐batch reactor to explore the possibility of the water reuse. The experimental results revealed that ozone was very effective in disinfection of the red‐meat‐processing wastewater. After 8 min of ozonation with an applied ozone dose of 23.09 mg min^?1 liter^?1 of wastewater, 99% of aerobic bacteria, total coliforms and Escherichia coli were inactivated. Empirical models were developed to predict the microbial inactivation efficacy of ozone from the CT values for the real red‐meat‐processing wastewater. A correlation was also derived to estimate the CT values from the applied ozone dose and the ozone contact time. The results also revealed that under the ozonation condition for 99% inactivation of aerobic bacteria, total coliforms and E coli, the decrease in the chemical oxygen demand and the 5‐day biological oxygen demand of the wastewater were 10.7% and 23.6%, respectively. However, ozonation under this condition neither improved the light transmission nor reduced the total suspended solids (TSS) despite of the decolorization of the wastewater after ozonation. Copyright © 2005 Society of Chemical Industry     

Optimization of cell wall disruption and lipid extraction methods by combining different solvents from wet Chlorella vulgaris

Over the past few decades, microalgae have emerged as a promising option for making lipid-based bioactive compounds. The purpose of this study was to extract lipids from Chlorella vulgaris. In this study, different cell wall disruption methods such as microwave, liquid nitrogen, ultrasound (US), and bead mill were compared. We selected and optimized two systems based on their efficacy in disrupting cell walls—US and beads mill. Based on the dry weight of C. vulgaris biomass, the maximum lipid extraction by the US was 17.1% and by bead mill was 15.2%. Following cell wall disruption of C. vulgaris, chloroform–methanol (2:1) solvent combination achieved high lipid extraction. However, the hexane–ethanol (1:1) solvent combination was chosen because of its lower toxicity. Specifically, the effect of the solvent-to-biomass ratio, the temperature, and the extraction time was investigated. The results indicated that the chloroform–methanol solvent combination yielded optimal results at 8 ml/g solvents to biomass, 45°C, and 60 min and that the hexane–ethanol combination yielded optimal results at 6 ml/g, 35°C, and 73 min, respectively. The highest amount of lipids was obtained from C. vulgaris with 87.6% moisture content. As a cell wall disruption method, the US obtained 20.4% and 16.4% with a combination of chloroform–methanol solvents and hexane–ethanol, respectively. Additionally, bead milling resulted in the highest extraction yield of 17.6% for chloroform–methanol and 13.9% for hexane–ethanol. Based on the results of cell wall disruption, the US method is the most efficient cell wall disruption method in terms of lipid extraction efficiency.