Venezuela Orinoco heavy crude oil was sequentially separated into several subfractions to determine the contents and types of vanadyl porphyrins contained in the products. Vanadium contents in each subfraction were detected using an atomic absorption spectrometer (AAS) combined with the characterization of vanadyl porphyrins by ultraviolet–visible (UV–vis) spectroscopy and positive-ion electrospray ionization (ESI) Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICR MS). Six types of petroleum vanadyl porphyrins, which have been identified previously, were well-characterized with the detailed fractionation. Three new series of vanadyl porphyrins corresponding to molecules of C n H m N4VO2, C n H m N4VO3, and C n H m N4VO4, respectively, were identified in addition to the six known types of vanadyl porphyrins.

These results demonstrated the active targeting ability of this kind of mannan-modified DNA-loaded vehicles, which may have great potential for targeted gene delivery.

A low molecular mass cutinase (designated TtcutA) from Thielavia terrestris was purified and biochemically characterized. The thermophilic fungus T. terrestris CAU709 secreted a highly active cutinase (90.4 U ml(-1)) in fermentation broth containing wheat bran as the carbon source. The cutinase was purified 19-fold with a recovery yield of 4.8 %. The molecular mass of the purified TtcutA was determined as 25.3 and 22.8 kDa using SDS-PAGE and gel filtration, respectively. TtcutA displayed optimal activity at pH 4.0 and 50 °C. It was highly stable up to 65 °C and in the broad pH range 2.5-10.5. Extreme stability in high concentrations (80 %, v/v) of solvents such as methanol, ethanol, acetone, acetonitrile, isopropanol, and dimethyl sulfoxide was observed for the enzyme. The K (m) values for this enzyme towards p-nitrophenyl (pNP) acetate, pNP butyrate, and pNP caproate were 7.7, 1.0, and 0.52 mM, respectively. TtcutA was able to efficiently degrade various ester polymers, including cutin, polyethylene terephthalate (PET), polycaprolactone (PCL), and poly(butylene succinate) (PBS) at hydrolytic rates of 3 μmol h(-1) mg(-1) protein, 1.1 mg h(-1) mg(-1) protein, 203.6 mg h(-1) mg(-1) protein, and 56.4 mg h(-1) mg(-1) protein, respectively. Because of these unique biochemical properties, TtcutA of T. terrestris may be useful in various industrial applications in the future.

Cyclonic (anticyclonic) oceanic eddies drive local upwelling (downwelling), leaving footprints in the sea surface temperature (SST) field as local extremes. Satellite-measured SST images can therefore be used to obtain information of the characteristics of oceanic eddies. Remotely sensed measurements represent very large data sets, both spatially and temporally. Manual eddy detection and analysis are thus practically impossible. In this letter, an automated scheme for eddy detection from remote sensing SST data is presented. The method is based on the analysis of velocity fields derived from SST measurements (thermal-wind velocity field). Using the geometric features of the velocity field, we can identify positions of eddy centers and derive eddy size, intensity, path, and lifetime. The scheme is applied to a realistic remotely sensed SST data set in a strong eddy activity region: Kuroshio Extension region

Content of total proanthocyanidins as well as total phenolics, flavonoids, antioxidant activities were evaluated for litchi (Litchi chinensis Sonn.) pulp of 32 cultivars. One cultivar, Hemaoli, showed the highest total proanthocyanidins and total phenolics, and DPPH or ABTS radical scavenging activities. ESI-MS and NMR analysis of the Hemaoli pulp crude extracts (HPCE) showed that procyandins composed of (epi)catechin unites with degree of polymerization (DP) of 2–6 were dominant proanthocyanidins in HPCE. After the HPCE was fractionated by a Sephadex LH-20 column, 32 procyanidins were identified by LC-ESI-Q-TOF-MS in litchi pulp for the first time. Quantification of individual procyanidin in HPCE indicated that epicatechin, procyanidin B2, procyanidin C1 and A-type procyanidin trimer were the main procyanidins. The radical scavenging activities of different fractions of HPCE as well as six procyanidins standards were evaluated by both DPPH and ABTS assays. HPCE fractions showed similar antioxidant activities with those of Vc and six individual procyanidins, the IC50 of which ranged from 1.88 ± 0.01 to 2.82 ± 0.10 μg/ml for DPPH assay, and from 1.52 ± 0.17 to 2.71 ± 0.15 μg/ml for ABTS assay. Such results indicate that litchi cultivars rich in proanthocyanidins are good resources of dietary antioxidants and have the potential to contribute to human health.

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