Learn More
Lipoxygenase (LOX) from eggplant (Solanum melongena L. cv. Belleza negra) was partially purified, and the products and kinetics of the enzyme were studied. Linoleic acid (LA) was the best substrate for this enzyme. Product analysis by HPLC and GC/MS revealed that, at its pH optimum (pH 7.0), the enzyme converted LA almost totally into the 9-hydroperoxy(More)
Fatty acid hydroperoxide lyase (HPO-lyase) was purified 300-fold from tomatoes. The enzymatic activity appeared to be very unstable, but addition of Triton X100 and beta-mercaptoethanol to the buffer yielded an active enzyme that could be stored for several months at -80 degrees C. The enzyme was inhibited by desferoxamine mesylate (desferal),(More)
Soybean lipoxygenase-1 is able to oxidize dilinoleoyl phosphatidylcholine at pH 7.5 and 10. The reaction could be followed spectrophotometrically from the increase of the absorbance at 234 nm. An intermediate product and a final product were detected. In the intermediate product only one of the linoleoyl chains (either sn1 or sn2) was oxidized. In the final(More)
The aim of this study was to reassess the use of autofluorescence for evaluating AM colonization in mycorrhizal roots in the light of criticisms of this method that affirmed that only metabolically inactive arbuscules autofluoresce. It was also investigated whether other mycorrhizal structures, such as hyphae, vesicles and spores, could be detected by(More)
Lipoxygenase (LOX) (EC 1.13.11.12) oxidized a wide range of phenothiazine (Pt) tranquillizers to their corresponding radical cations in the presence of H2O2 by means of an enzymatic chemical second-order mechanism with substrate regeneration similar to that of horseradish peroxidase. The optimum pH of LOX for this hydroperoxidase activity was in the acid(More)
The hydroperoxidase activity of soybean lipoxygenase, a non-heme protein, oxidizes chlorpromazine using H2O2 at acidic pHs ranging from 3.0 to 4.0. The enzyme is assayed at pH 3.5, at which the half-life is 2 h (lower pHs cause higher inactivation rates). This oxidation is enzymatical since boiled enzyme or even iron ions both with H2O2 failed to produce(More)
In the present paper, a fully latent polyphenol oxidase (PPO) from desert truffle (Terfezia claveryi Chatin) ascocarps is described for the first time. The enzyme was partially purified by using phase partitioning in Triton X-114 (TX-114). The achieved purification was 2-fold from a crude extract, with a 66% recovery of activity. The interfering lipids were(More)
The influence of inorganic and organic phosphorus (P) and the absence of P in the culture medium on the type of mycorrhizal colonization formed (ecto-, ectendo-, or endomycorrhiza) during Helianthemum almeriense x Terfezia claveryi symbiosis in in vitro conditions was analyzed. This is the first time that the relative proportions of the different(More)
In the present paper, we confirmed that alkaline phosphatase (ALP) is the main phosphatase present in ascocarps of the edible mycorrhizal fungus Terfezia claveryi. The enzyme was partially purified by precipitation with polyethylene glycol. The purification achieved from a crude extract was fivefold, with 53% of the activity recovered, and acid phosphatase,(More)
Patatin is a family of glycoproteins that accounts for 30-40% of the total soluble protein in potato (Solanum tuberosum L.) tubers. This protein has been reported to serve as a storage protein and also to exhibit lipid phospholipase activity. This paper describes a simple continuous spectrophotometric method for assaying patatin phospholipase activity. The(More)