Pristane Research Articles

Osteoarticular protection of Zea mays L. purple variety (purple corn) in experimental arthritis in rats

To evaluate the protective effect of Zea mays L., purple variety (purple corn) against inflammatory response and osteoarticular damage in rats with experimental arthritis. Sixty-five Holtzman rats were used, assigned to seven groups: G1 (n=5): control; G2 (n=10): pristane (PIA) + distilled water; G3 (n=10): PIA + methotrexate 0.1 mg/kg; G4 (n=10): PIA + indomethacin 0.6 mg/kg; G5 (n=10): PIA + Zea mays 100 mg/kg; G6 (n=10): PIA + Zea mays 1000 mg/kg, and G7 (n=10): PIA + methotrexate 0.1 mg/kg + Zea mays 1000 mg/kg. Treatments were administered by orogastric cannula daily for 21 days; pristane was administered subdermal only on day 1. Volume of hind leg was recorded with a digital plethysmometer. The radiological analysis of the legs was evaluated according to the modified Clark criteria. The percentage of inflammation at the end of the experiment was: (G1) 1.50 ± 0.5; (G2) 13.73 ± 8.4; (G3) 14.76 ± 8.8; (G4) 14.22 ± 9.0; (G5) 10.81 ± 9.1; (G6) 5.31 ± 1.4; (G7) 6.38 ± 0.5. The radiological scores of the affected areas were: (G1) 0.6; (G2) 3.5; (G3) 0.6; (G4) 1.7; (G5) 1.9; (G6) 1.4; (G7) 1.0. Only the groups Zea mays L. 1000 mg/kg and methotrexate + Zea mays L. 1000 mg/kg showed a significantly lower inflammatory response (p<0.05) and showed significantly lower joint scores in relation to PIA. Zea mays L. (purple corn) reduces the inflammatory process and radiological modifications of PIA-induced arthritis in rats in a dose-dependent manner.

Fisetin inhibits pristine-induced systemic lupus erythematosus in a murine model through CXCLs regulation.

Systemic lupus erythematosus (SLE) is associated with an increased risk of vascular complications. Lupus nephritis is a major manifestation of SLE in the clinic. Lupus nephritis is elevated by T helper type 17 (Th17) cells, the major pro-inflammatory T-cell subset, leading to autoimmunity modulation. Therapeutic treatments targeting leukocyte recruitment may be useful in attenuating vascular complications linked to SLE progression. 3,7,3',4'-Tetrahydroxyflavone (fisetin) is a flavonol and a member of the flavonoid polyphenols. It is present in various fruits and vegetables, including persimmons, apples, kiwis, grapes, onions, strawberries and cucumbers. In the present study, the effects of fisetin against SLE induced by pristane (PRI) were evaluated in mice. Fisetin was indicated to reduce PRI-induced anti-double stranded DNA, anti- small nuclear ribonucleoprotein and the ratio of albumin to creatinine in urine. In addition, the chemokine (C-X-C motif) ligand (CXCL) signaling pathway was activated for PRI treatment, which was reversed by fisetin administration by reducing CXCL-1 and 2, chemokine (C-C motif) ligand 3, as well as CXC receptor 2 expression. In addition, the induction of inflammatory cytokines, including interleukin (IL)-6, tumor necrosis factor-α, IL-1β, as well as the chemokine interferon-γ, by PRI were downregulated by fisetin treatment in mice. Furthermore, Th17 cells and their associated cytokines were highly induced by PRI treatment, which was inhibited by fisetin administration. The present results indicated that fisetin may be an effective management for SLE by targeting the CXCL signaling pathway and regulating Th17 differentiation during lupus nephritis development.

Bio-Degradation of Pristane in Mixed Alkanes by a Mixed Culture Containing Nocardia corynebacterioides

Gram-positive bacterium identified as Nocardia cotynebacterioides L29-2 was isolated from a diesel oil contaminated site in southern Taiwan. The bacterium was found able to degrade both straight and branched alkanes in diesel oil. Inorganic nutrients were not able to enhance the growth of the cells but the cell growth and hydrocarbon biodegradation could be accelerated by adding yeast extract. It was found that this bacterium was able to degrade pristane at high efficiency. However, the ability of pristane biodegradation was severely inhibited by the presence of normal alkanes. The diesel oil biodegradation was significantly improved by introducing another bacterium, Rhodococcus globerulus H425-2, found in the same contaminated site. Rhodococcus globerulus H425-2 was found to degrade normal alkanes at a much higher rate than Nocardia corynebacterioides L29-2. In this study, the biodegradation of pristane and n-pentadecane in single substrate and mixed substrate experiments were compared. The cooperation of Nocardia corynebacterioides L29-2 and Rhodococcus globerulus H425-2 was also under investigation. It appeared that the 1:1 ratio was close to the optimum inoculation ratio of these two species for degrading the mixture of pristane and n-pentadecane at 1:1 ratio. The results indicate that the addition of organic nutrients and the proper control of the population ratio according to the alkane composition in the contaminated site are crucial for effective bioremediation of diesel spill.

Biodegradation of crude oil across a wide range of salinities by an extremely halotolerant bacterial consortium MPD-M, immobilized onto polypropylene fibers.

The bacterial consortium MPD-M, isolated from sediment associated with Colombian mangrove roots, was effective in the treatment of hydrocarbons in water with salinities varying from 0 to 180 g L(-1). Where the salinity of the culture medium surpassed 20 g L(-1), its effectiveness increased when the cells were immobilized on polypropylene fibers. Over the range of salinity evaluated, the immobilized cells significantly enhanced the biodegradation rate of crude oil compared with free-living cells, especially with increasing salinity in the culture medium. Contrary to that observed in free cell systems, the bacterial consortium MPD-M was highly stable in immobilized systems and it was not greatly affected by increments in salinity. Biodegradation was evident even at the highest salinity evaluated (180 g L(-1)), where biodegradation was between 4 and 7 times higher with immobilized cells compared to free cells. The biodegradation of pristane (PR) and phytane (PH) and of the aromatic fraction was also increased using cells immobilized on polypropylene fibers.

GEOCHEMICAL CHARACTERIZATION OF LOWER TOARCIAN SOURCE ROCKS FROM NW GERMANY: INTERPRETATION OF AROMATIC AND SATURATED HYDROCARBONS IN RELATION TO DEPOSITIONAL ENVIRONMENT AND MATURATION EFFECTS

The characterization of crude oils in terms of source rock facies and depositional environment, as well as their maturity and alteration stage, is a crucial element in exploration studies. The present contribution has implications for oil‐oil and oil‐source rock correlations. In the past, numerous parameters have been used for this purpose most of which are based on the analysis of saturated and aromatic hydrocarbons (including sulphur aromatics) and also on stable isotope signatures and elemental compositions. Recently, molecular indicators based on dibenzothiophene (DBT), phenanthrene (PHE) and their methyl derivatives methyldibenzothiophene (MDBT) and methylphenanthrene, as well as pristane (PRI) and phytane (PHY), have also been proposed (Hughes et al., 1995). These studies have attempted to infer a crude oil's source rock facies and lithology, and to classify the source rock's depositional environment. In the present study, the above compounds have been quantified by solvent extraction, liquid chromatography and capillary gas chromatography in 98 core samples of the Lower Toarcian Posidonia Shale Formation, a source rock in NW Germany. Most samples, cored between depths of 7m and 70 m, came from the Hils Half‐Graben in the Lower Saxony Basin. With a few exceptions from one borehole, the samples were unweathered marls or calcareous shales. The rocks contained mainly marine organic matter (Type II kerogen), the thermal maturity of which ranged from early mature to postmature (corresponding to 0.48‐1.44% mean vitrinite reflectance), therefore encompassing the range over which effective petroleum generation had occurred. We found that the influences of organic matter type and maturity on the molecular distributions of the above compounds were not obvious when interpreted in terms of a DBT/PHE vs PRI/PHY diagram. However, Principal Component Analysis (PCA) of our data‐set showed that alkylphenanthrene concentrations are strongly controlled by maturity, while the concentrations of PRI, PHY, and 1‐MDBT display a distinct source effect.

Myeloma proteins that bind Hsp65 (GroEL) are polyreactive and are found in high incidence in pristine induced plasmacytomas.

The myeloma proteins produced by 44 plasmacytomas (PCTs) recently induced by pristane in BALB/cAnPt and closely related PCT susceptible congenic strains of mice were isolated chromatographically and screened against a panel of 10 protein, nucleic acid and lipid antigens. This sample was highly unusual because 82% of the proteins had IgG isotopes. Nine of the proteins bound to Hsp65 (GroEL), and all of these were polyreactative. Twenty-one of the myeloma proteins were polyreactive and bound two or more antigens in the panel, and five were monoreactive. Thus, an antigen binding activity was determined for 59% of these myeloma proteins.

Separation of Pristane from Herring.

Separation of Pristane from Herring.

Studies Related to Pristane. V. The Constitution of Zamene.

Studies Related to Pristane. V. The Constitution of Zamene.