Olive detection

Figure 12.1 Analysis of Tinuvin 1577 in 30% virgin olive oil (in hexane), showing (a) the gas cliromatogram comparing the pure oil with a sample at the Tinuvin 1577 detection limit concentration, and (b) the coixesponding liquid chromatogram. Reprinted from Journal of High Resolution Chromatography, 20, A. L. Baner and A. Guggenberger, Analysis of Tinuvin 1577 polymer additive in edible oils using on-line coupled HPLC-GC , pp. 669-673, 1997, with pennission from Wiley-VCH.

Cherry and Crandall in 1932 (86) used olive oil as substrate with gum acacia as the emufsTfier. This method has served as the basis for a number of modifications that increased the stability of the emulsion, decreased incubation time and gave better precision. When a serum sample is incubated with a stabilized olive oil emulsion, lipase acts at the interface of substrate and water to hydrolyze olive oil into fatty acid plus diglycerides, and to a small extent to monoglycerides and glycerol. The bile salt sodium deoxycholate activates the reaction. These methods measure the liberated fatty acids by titration with a standardized NaOH solution. An indicator such as phenolphatalein, thymolphthalein or methyl red or a pH meter are used to detect the end point. 

A traditional system for the preparation of table olives, involves a treatment of the fresh fruit with a solution of NaOH to hydrolised the bitter glycoside oleuropein, followed by a lactic fermentation in brine. The modifications that take place on pectic polysaccharides of olives (Manzanilla variety) during this process was smdied. Processing induced a net loss of polysaccharides soluble in sodium carbonate and a paralel accumulation of water and Imidazole/HCl soluble polysaccharides. A general decrease of the apparent molecular weight of water and carbonate soluble polysaccharides was also detected. 

Total pectinase, cellulase and lipase activities secreted by colonies were detected on BSM plates containing respectively 1% of citrus pectin, 2% Walseth cellulose and 1% olive oil + rhodamine. After few days at 30°C, pectin plates were covered by 1% CTAB for Ihour, positive colonies became surrounded by a clear halo walseth plates are not stained the halo is visible directly on positive clones lipase activity is revealed under UV on oil-rhodamine plates. 

The application of 13C NMR for the rapid analysis of the oil composition of oil seeds is well known [16], 13C NMR has recently been applied to the quantitative analysis of the most abundant fatty acids in olive oil [17]. The values obtained by this method differed by only up to 5% compared with GLC analysis. The quantitative analysis was applied to the olefmic region of the high resolution 13C NMR spectrum of virgin olive oil to detect adulteration by other oils which differed significantly in their fatty acid composition. The application of the methodology for the detection of adulteration of olive oil by hazelnut oil is more challenging as both oils have similar chemical profiles and further experiments are in progress. 

Lawrence and Ducharme [489] have described a fast, simplified method for the detection of fluorescent whiteners in polymers, in which the polymer dissolution was applied directly to the thin layer. Also the separation of optical brighteners (Leucopur EGM, Azur 4, Azur 5, Hostalux ABC, Uvitex OB, Eastobrite OB) from plastics and migration into water and olive oil was studied by HPTLC on RP-18 silica using various mobile phase mixtures and UV detection [490]. 

Bertolini, E. Penyalver, R. Garcia, A. Olmos, A. Quesada, J. M. Cambra, M. Lopez, M. M. Highly sensitive detection of Pseudomonas savastanoi pv. savas-tanoi in asymptomatic olive plants by nested-PCR in a single closed tube./. Microbiol. Meth. 2003,52, 261-266. 

Oliver, SE, D Gunnell, J Donovan et al. 2004. Screen-detected prostate cancer and the insulin-like growth factor axis results of a population-based case-control study (United States). Int J Cancer 108(6) 887-892. 

Aqueous simulants — HPLC with UV detection. Olive oil extracted with dilute sodium hydrogen carbonate and the aqueous extract acidified and examined by HPLC Headspace GC with automated sample injection and specific nitrogen detector. Confirmation by GC-MS if required Headspace GC of the polymer dissolved in N,N-dimethylacetamide. 

GC of aqueous simulant or water extract of olive oil using cold on-column injector. 1,4 butane diol internal standard Solvent extraction with dichloromethane and concurrent derivatisation with 9-(methylaminomethyl)anthracene. Fluorescent derivatives analysed by HPLC with fluorescence detection... 

Bis-derivitisation with fluorescamine and HPLC with fluorescence detection Aqueous simulants — HPLC with fluorescence detection. Olive oil extracted with methanol /water after addition of hexane Aqueous simulants — HPLC with UV detection. Olive oil extracted with 80% aqueous acetonitrile Headspace GC with FID detection and pentane internal standard Aqueous simulants GC. Olive oil extracted with water/ethanol and GC detection... 

Aqueous simulants examined by HPLC with UV detection. Olive oil extracted with distilled water, with determination in the water extract... 

Part 27 Determination of 2,4,6-triamino-1,3,5-triazine in food simulants Aqueous simulants — HPLC with UV detection 230 nm. Olive oil extracted with water/isopropanol... 

By the nature of the process by which olive oil is extracted from the olive, the oil is susceptible to contamination. The high price associated with olive oil of the highest purity— extra virgin olive oil — also leads to falsification by unscrupulous vendors who blend with less costly oils such as com, peanut, and soybean oil. Various analytical techniques have been devised to authenticate the purity of olive oil by detecting certain oil components. 

DCIA has been used to label numerous proteins and other biomolecules, including phospholipids (Silvius et al., 1987), to study the interaction of mRNA with the 30S ribosomal subunit (Czworkowski et al., 1991), in the investigation of cellular thiol components by flow cytometry (Durand and Olive, 1983), in the detection of carboxylate compounds using peroxyoxalate chemiluminescence (Grayeski and DeVasto, 1987), and for general sulfhydryl labeling (Sippel, 1981). 

Olive PL (1988) DNA precipitation assay a rapid and simple method for detecting DNA damage in mammalian cells. Environ Mol Mutagen ll(4) 487-495... 

Hexachloroethane is rarely detected in ambient water. Data reported in the STORET database indicate that the chemical was detectable in only 1 of 882 (0.1%) ambient water samples (Staples et al. 1985). The median concentration for all samples was <10 pg/L. Hexachloroethane was detected in Lake Ontario water, but not in Lake Erie (International Joint Commission 1983). The concentration of hexachloroethane in Lake Ontario was reported at 0.02 ng/L (Oliver and Niimi 1983). It was also identified in leachate from a hazardous waste site in Niagara Falls, New York (Hauser and Bromberg 1982). Hexachloroethane was not detected in 86 samples of urban runoff from 15 cities analyzed for the National Urban Runoff Program (Cole et al. 1984). 

Hexachloroethane has not generally been reported in foods. Hexachloroethane was not detected in 116 fish samples reported in the STORET database (Staples et al. 1985), nor was it detected in 28 fish samples from 14 Lake Michigan tributaries (Camanzo et al. 1987). However, hexachloroethane was detected in 10 of 10 Lake Ontario rainbow trout at an average concentration of 0.03 ng/g (Oliver and Niimi 1983). No information was located regarding hexachloroethane in other foods. 

Ambient air may also be collected on adsorbent traps (Krost et al. 1982 Oliver et al. 1996) or in stainless steel canisters (Anlauf et al. 1985 EPA 1988 McLaren et al. 1996). Detection limits, where reported, are in the low ppb to low parts per trillion (ppt) range (Anlauf et al. 1985 McLaren et al. 1996 Oliver et al. 1996). Recovery of 75-98% (for all compounds tested) has been reported for collection on Tenax adsorbent (Krost et al. 1982). Passive monitors are utilized for ambient air and indoor air (Cao and Hewitt 1993 Fellin and Otson 1994 Otson et al. 1994). Detection limits in the low ppb range have been reported (Otson et al. 1994). 

If analytical methods are at the heart of biopharmaceutical development and manufacturing, then protein concentration methods are the workhorse assays. A time and motion study of the discovery, development, and manufacture of a protein-based product would probably confirm the most frequently performed assay to be protein concentration. In the 1940s Oliver H. Lowry developed the Lowry method while attempting to detect miniscule amounts of substances in blood. In 1951 his method was published in the Journal of Biological Chemistry. In 1996 the Institute for Scientific Information (ISI) reported that this article had been cited almost a quarter of a million times, making it the most cited research article in history. This statistic reveals the ubiquity of protein measurement assays and the resilience of an assay developed over 60 years ago. The Lowry method remains one of the most popular colorimetric protein assays in biopharmaceutical development, although many alternative assays now exist. 

Rats exposed acutely by gavage to 110 mg/kg of 1,2-dibromoethane in olive oil had elevated concentrations of the parent compound in the blood up to 30 minutes after exposure. At 2 and 4 hours postexposure, only trace amounts were detected and by 13 hours after exposure,... 

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