Classification of pumpkin seed oils according to their species and genetic variety by attenuated total reflection Fourier-transform infrared spectroscopy

Attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR), followed by multivariate treatment of the spectral data, was used to classify seed oils of the genus Cucurbita (pumpkins) according to their species as C. maxima, C. pepo, and C. moschata. Also, C. moschata seed oils were classified according to their genetic variety as RG, Inivit C-88, and Inivit C-2000. Up to 23 wavelength regions were selected on the spectra, each region corresponding to a peak or shoulder. The normalized absorbance peak areas within these regions were used as predictors. Using linear discriminant analysis (LDA), an excellent resolution among all categories concerning both Cucurbita species and C. moschata varieties was achieved. The proposed method was straightforward and quick and can be easily implemented. Quality control of pumpkin seed oils is important because Cucurbita species and genetic variety are both related to the pharmaceutical properties of the oils.     

Antioxidant activity of ethanolic extracts from several asparagus cultivars

Three different methods (antiradical activity, inhibition of primary oxidation, and ferric reducing power) have been used to evaluate the antioxidant activity of eight different asparagus cultivars and byproducts: white and green asparagus from Alcalá del Río (Guadalquivir Valley, Seville) and American hybrids, native spears, and their byproducts from Huétor-Tájar (Vega de Granada). The correlation between antioxidant activity and total phenol content was studied. Six standards were also tested to validate the modified methods for antioxidant activity determination. Results obtained for antiradical capacity and reducing power were very similar, and a high correlation with phenols was found (R > or = 0.9 for both tests). Sample origin was an important factor, spears from Huétor-Tájar having higher values (ARC between 7 and 10 and P(R) of 0.25-0.33) than those from Alcalá del Río (ARC 0.6-2 and P(R) of 0.05-0.07). Significant differences were found between spears with the same origin, suggesting that genetics are another factor to take into account. Asparagus inhibits lipid primary oxidation, but no correlation between the inhibition percentage and phenols was observed. Asparagus origin was the only factor that led to significant differences: samples from Huétor-Tájar had higher values (POIC between 18 and 32) than those from Alcalá del Río (POIC of 5-9). Byproducts from the canning industry at Huétor-Tájar were also assayed for antioxidant activity; the results obtained suggested that byproducts could be considered as an excellent source of natural antioxidants.     

Development of an analytical scheme for simazine and 2,4-D in soil and water runoff from ornamental plant nursery plots

The transport and fate of pesticides applied to ornamental plant nursery crops are not well documented. Methodology for analysis of soil and water runoff samples concomitantly containing the herbicides simazine (1-chloro-4,6-bis(ethylamino)-s-triazine) and 2,4-D ((2,4-dichlorophenoxy)acetic acid) was developed in this research to investigate the potential for runoff and leaching from ornamental nursery plots. Solid-phase extraction was used prior to analysis by gas chromatography and liquid chromatography. Chromatographic results were compared with determination by enzyme-linked immunoassay analysis. The significant analytical contributions of this research include (1) the development of a scheme using chromatographic mode sequencing for the fractionation of simazine and 2,4-D, (2) optimization of the homogeneous derivatization of 2,4-D using the methylating agent boron trifluoride in methanol as an alternative to in situ generation of diazomethane, and (3) the practical application of these techniques to field samples.     

Interrill and rill erodibility in the northern Andean Highlands

There is a lack of quantitative information describing the physical processes causing soil erosion in the Andean Highlands, especially those related to interrill and rill erodibility factors. To assess how susceptible are soils to erosion in this region, field measurements of interrill (Ki) and rill (Kr) erodibility factors were evaluated. These values were compared against two equations used by the Water Erosion Prediction Project (WEPP), and also compared against the Universal Soil Loss Equation (USLE) erodibility factor. Ki observed in situ ranged from 1.9 to 56 × 10⁵ kg s m^− 4 whereas Kr ranged from 0.3 to 14 × 10^− 3 s m^− 1. Sand, clay, silt, very fine sand and organic matter fractions were determined in order to apply WEPP and USLE procedures. Most of the evaluated soils had low erodibility values. However, the estimated USLE K values were in the low range of erodibility values. Stepwise multiple regression analyses were applied to ascertain the influence of the independent soil parameters on the Ki and Kr values. After this, we yield two empirical equations to estimate Ki and Kr under this Andean Highlands conditions. Ki was estimated using as predictors silt and very fine sand, while Kr used as predictors clay, very fine sand and organic matter content. Relationship among Ki, Kr and K are described for the Highland Andean soils.     

Countercurrent supercritical fluid extraction and fractionation of high-added-value compounds from a hexane extract of olive leaves

Countercurrent supercritical fluid extraction (CC-SFE) at a pilot scale plant was used for fractionation of high-added-value products from a raw extract of olive leaves in hexane. Compounds found in the raw extract were waxes, hydrocarbons, squalene, beta-carotene, triglycerides, alpha-tocopherol, beta-sitosterol, and alcohols. The CC-SFE extraction process was investigated according to a 2(3) full factorial experimental design using the following variables and ranges: extraction pressure, 75-200 bar; extraction temperature, 35-50 degrees C; and ethanol as modifier, 0-10%. Data were analyzed in terms of extraction yield, enrichment, recovery, and selectivity. Higher extraction yields were attained at 200 bar. For most of the compounds analyzed enrichment was attained at the same conditions, that is, 75 bar, 35 degrees C, and 10% ethanol. Hydrocarbons were usually recovered in the separators, whereas waxes and alpha-tocopherol remain in the raffinate. Selectivity data reveal that alpha-tocopherol is the most easily separable compound. The influence of the experimental factors on the recovery of all the compounds was studied by means of regression models. The best fitted model was attained for beta-sitosterol, with R2 = 99.25%.     

Plant and animal species composition and heavy metal content in fly ash ecosystems

Plant and animal species present on a coal fly ash slurry pond site and a dry deposit site were surveyed and sampled during a two-day period in October. Elemental analyses were determined for most of the species encountered. A total of 48 plant species were observed on the two sites, with 35 species on the wet site, and 20 on the dry site. Eighteen terrestrial and 7 aquatic animal species were found on the wet site, exclusive of vertebrates which were not studied with the exception of a carp (Cyprinus carpio). Eleven terrestrial invertebrates and one aquatic species were observed on the dry site. Neutron activation analysis was carried out for: Se, Hg, Cr, Ni, Zn, Co, Sb, Cd, and As. Using literature values for phytotoxicity, we conclude that, in general, plants did not accumulate toxic levels of metals. Only one plant (Impatiens biflora Willd.) showed a significant level of Cd. Of 20 plants analyzed on the wet site, 10 had excessive Se concentrations (>5 ppm); on the dry site 6 out of 18 had high Se values. In animals (Gryllus sp.; Melanoplus sp.; Trachelipus sp.; Lumbricus terrestris; Physa integra; Cyprinus carpio) the trace metal concentration was generally in between that of control animals and that of the fly ash itself. One exception included Zn, which, although the most variable element examined, was concentrated in all the terrestrial animals to levels higher than in fly ash. Crickets are the most consistent bioconcentrators with Cr, Se, and Zn at higher levels than for control animals. All animal species studied accumulated Se compared to controls.     

Fumonisin B-glucose reaction products are less toxic when fed to swine

The effects of fumonisin B-glucose reaction products in swine diets was examined. Pigs were fed diets containing 528 micromol of total fumonisin B/kg (FB), 528 micromol of total FB-glucose adducts/kg (FB-G, 122 micromol of unreacted FB/kg), or 0 micromol of total FB/kg for 15 days to test the efficacy of the FB-G reaction products in detoxifying FB. Weight gain in FB pigs was lower than in FB-G or controls, which was correlated with feed intake reduction in FB pigs. Serum aspartate aminotransferase, gamma-glutamyltransferase, and total bilirubin in FB pigs were higher than in FB-G or control pigs. Serum sphinganine/shingosine ratios in FB pigs were higher than in FB-G or control pigs. Microscopic examination of tissues from FB pigs showed generalized liver necrosis and apoptosis with marked cellular pleomorphism and disorganized hepatic cords. The liver and kidneys in the FB-G group appeared to be normal. Tissues of controls were free of lesions. Results suggest that dietary FB-G products are less toxic to swine and may provide an detoxification approach in instances of widespread FB grain contamination (p < 0.05).