Effect of the addition of sewage sludge as a fertilizer on a sandy vineyard soil

Purpose

The application of sludge from wastewater in agriculture has increased in recent years, and it is therefore important to assess the effect that such treatment has on both the soil and the plant. The aim of the study described here was to ascertain whether there is a variation in the properties of the soil and to determine if this addition has an impact on the plant.

Materials and methods

The area of investigation was close to the municipality of Villarrubia de los Ojos (Ciudad Real). In this work, six samples were taken from the surface horizon in the studied plot at a depth of 35 cm. A further three samples were taken: (i) a surface horizon of a soil close to the area under investigation but without treatment (control sample), (ii) a sample of sludge from the wastewater treatment plant and (iii) a sample of the mixture used by farmers as fertilizer. Laboratory tests were conducted in accordance with the SCS-USDA (1972) guidelines. Trace element samples were analysed by X-ray fluorescence spectrophotometry (Philips PW 2404).

Results and discussion

The parcel of land studied is dominated by a sandy texture (88.3 % sand), and a decrease in pH was observed in areas in which the mixture (manure + sludge) was added (pH?=?8.0) compared to areas in which fertilizer was not applied (pH?=?8.5). It was observed that the addition of the compound led to an increase in the electrical conductivity of the soil. The trace elements can be organized into two groups based on the results obtained in this study. One group contains the trace elements that were only present in the rows that were treated with the fertilizer. The other group of trace elements was mobilized throughout the whole plot.

Conclusions

The application of sewage sludge on agricultural soils can be very useful as an organic amendment because it produces an increase in soil organic matter. However, sewage sludge must be applied with caution due to the changes in soil chemical properties (for example, pH and E.C.). The use of this type of waste for prolonged periods of time can cause problems of contamination in the soil.

     

Identification and quantification of cyclolinopeptides in five flaxseed cultivars

Cyclolinopeptides are a group of naturally occurring hydrophobic cyclic peptides found in flaxseed and flax oil that have immunosuppressive activity. This study describes the measurement of flaxseed cyclolinopeptide concentrations using an internal standard HPLC method. In addition, the concentration of cyclolinopeptides in the seed of Canadian flax cultivars grown at two locations over two years is reported. The data are consistent with the formation of flaxseed cyclolinopeptides from two ribosome-derived precursors. Each precursor protein includes the sequences corresponding to three cyclolinopeptides from which those cyclolinopeptides are presumably derived by precursor processing. The concentrations of cyclolinopeptides C and E, which are encoded by the same gene sequence, are highly correlated, and the concentrations of cyclolinopeptides D, F, and G, which are encoded by a second gene sequence, are also highly correlated. The strong correlation between the cyclolinopeptides arising from the same gene may prove to be important in understanding how peptide concentration is controlled. Additional research may lead to approaches to improve flax either as a platform for peptide production or as a source of oil with improved drying properties and flavor.     

The dissipation of tebuconazole and propiconazole in boronia (Boronia megastigma Nees)

The broad spectrum, systemic fungicides tebuconazole and propiconazole are used to control rust in boronia (Boronia megastigma Nees). Gas chromatography combined with either a benchtop quadrupole mass spectrometer or a high-resolution mass spectrometer allowed for the monitoring of both pesticides in boronia leaves, flowers, and concrete. Field trials were established at two sites to determine the rate of dissipation of tebuconazole and propiconazole in boronia. At site 1, two application rates of 125 and 250 g active ingredient/hectare (ai/ha) tebuconazole were employed. Treatments were repeated 17 days later. At harvest, 286 days after the final application, tebuconazole was detected at levels of 0.06 +/- 0.05 and 0.5 +/- 0.1 [mg/kg +/- standard error, on a dry matter basis (DMB)] in the leaves collected from plots treated with 125 and 250 g ai/ha of tebuconazole, respectively. The oil produced from the flowers collected at the final harvest had residues of tebuconazole at levels of 0.06 +/- 0.03 and 0.10 +/- 0.08 mg/kg for the 125 and 250 g ai/ha application rates, respectively. Two repeat applications of 125 g ai/ha propiconazole were also used at site 1. Residues of propiconazole were detected at 0.09 +/- 0.03 mg/kg (DMB) 286 days after the final application. At site 2, treatments of 125 g ai/ha of tebuconazole were applied twice. At harvest, 279 days after the final application of tebuconazole, residues were recorded at 0.30 +/- 0.09 mg/kg in the leaves (DMB) while the oil produced had 0.20 +/- 0.07 mg/kg.     

On-line gas chromatography combustion/pyrolysis isotope ratio mass spectrometry (HRGC-C/P-IRMS) of pineapple (Ananas comosus L. Merr.) volatiles

By use of extracts prepared by liquid-liquid separation of the volatiles from self-prepared juices of pineapple fruits (Ananas comosus) (n = 14) as well as commercial pineapple recovery aromas/water phases (n = 3), on-line capillary gas chromatography-isotope ratio mass spectrometry was employed in the combustion (C) and the pyrolysis (P) modes (HRGC-C/P-IRMS) to determine the delta(13)C(VPDB) and delta(2)H(VSMOW) values of selected pineapple flavor constituents. In addition to methyl 2-methylbutanoate 1, ethyl 2-methylbutanoate 2, methyl hexanoate 3, ethyl hexanoate 4, and 2,5-dimethyl-4-methoxy-3[2H]-furanone 5, each originating from the fruit, the delta(13)C(VPDB) and delta(2)H(VSMOW) data of commercial synthetic 1-5 and "natural" (biotechnologically derived) 1-4 were determined. With delta(13)C(VPDB) data of pineapple volatiles 1-4 varying from -12.8 to -24.4 per thousand, the range expected for CAM metabolism was observed. Compound 5 showed higher depletion from -20.9 to -28.6 per thousand. A similar situation was given for the delta(2)H(VSMOW) values of 3-5 from pineapple ranging from -118 to -191 per thousand, whereas 1 and 2 showed higher depleted values from -184 to -263 per thousand. In nearly all cases, analytical differentiation of 1-5 from pineapple and natural as well as synthetic origin was possible. In general, natural and synthetic 1-5 exhibited delta(13)C(VPDB) data ranging from -11.8 to -32.2 per thousand and -22.7 to -35.9 per thousand, respectively. Their delta(2)H(VSMOW) data were in the range from -242 to -323 per thousand and -49 to -163 per thousand, respectively.     

Synthesis and characterization of canola oil-stearic acid-based trans-free structured lipids for possible margarine application

Incorporation of stearic acid into canola oil to produce trans-free structured lipid (SL) as a healthy alternative to partially hydrogenated fats for margarine formulation was investigated. Response surface methodology was used to study the effects of lipozyme RM IM from Rhizomucor miehei and Candida rugosa lipase isoform 1 (LIP1) and two acyl donors, stearic acid and ethyl stearate, on the incorporation. Lipozyme RM IM and ethyl stearate gave the best result. Gram quantities of SLs were synthesized using lipozyme RM IM, and the products were compared to SL made by chemical catalysis and fat from commercial margarines. After short-path distillation, the products were characterized by GC and RPHPLC-MS to obtain fatty acid and triacylglycerol profiles, 13C NMR spectrometry for regiospecific analysis, X-ray diffraction for crystal forms, and DSC for melting profile. Stearic acid was incorporated into canola oil, mainly at the sn-1,3 positions, for the lipase reaction, and no new trans fatty acids formed. Most SL products did not have adequate solid fat content or beta' crystal forms for tub margarine, although these may be suitable for light margarine formulation.     

Pathogens as drivers of population declines: The importance of systematic monitoring in great apes and other threatened mammals

Until recently, the focus of great ape behavioural and ecological research has been distinct from the focus of scientists working in medical and veterinary sciences. More scientists are calling for a connection between medical and field research due to recent disease outbreaks in great apes, including Ebola, and indications of cross-transmission of Ebola and other viruses between primates and humans. A major limitation to progress is the lack of information on infectious diseases and their transmission in wild primates. Here, we present examples of successful pathogen detection in wild great apes and describe approaches and techniques that can be used in the field, focusing in particular on investigation of deaths and non-invasive sample collection. This interdisciplinary approach is providing new insights to infectious diseases of great apes and is helping to protect the health of great ape populations. This framework can also be applied to other mammals under threat from infectious diseases, including African wild dogs, seals and Tasmanian devils. In addition to providing benefits for great ape conservation, research that integrates infectious disease with primate ecology provides insights to emerging diseases in humans and the role of disease in primate evolution.     

Conversion of the mycotoxin patulin to the less toxic desoxypatulinic acid by the biocontrol yeast Rhodosporidium kratochvilovae strain LS11

The infection of stored apples by the fungus Penicillium expansum causes the contamination of fruits and fruit-derived products with the mycotoxin patulin, which is a major issue in food safety. Fungal attack can be prevented by beneficial microorganisms, so-called biocontrol agents. Previous time-course thin layer chromatography analyses showed that the aerobic incubation of patulin with the biocontrol yeast Rhodosporidium kratochvilovae strain LS11 leads to the disappearance of the mycotoxin spot and the parallel emergence of two new spots, one of which disappears over time. In this work, we analyzed the biodegradation of patulin effected by LS11 through HPLC. The more stable of the two compounds was purified and characterized by nuclear magnetic resonance as desoxypatulinic acid, whose formation was also quantitated in patulin degradation experiments. After R. kratochvilovae LS11 had been incubated in the presence of (13)C-labeled patulin, label was traced to desoxypatulinic acid, thus proving that this compound derives from the metabolization of patulin by the yeast. Desoxypatulinic acid was much less toxic than patulin to human lymphocytes and, in contrast to patulin, did not react in vitro with the thiol-bearing tripeptide glutathione. The lower toxicity of desoxypatulinic acid is proposed to be a consequence of the hydrolysis of the lactone ring and the loss of functional groups that react with thiol groups. The formation of desoxypatulinic acid from patulin represents a novel biodegradation pathway that is also a detoxification process.     

Characterization and quantitation of low and high molecular weight phenolic compounds in apple seeds

The phenolic constituents of seeds of 12 different apple cultivars were fractionated by sequential extraction with aqueous acetone (30:70, v/v) and ethyl acetate after hexane extraction of the lipids. Low molecular weight phenolic compounds were individually quantitated by RP-HPLC-DAD. The contents of extractable and nonextractable procyanidins were determined by applying RP-HPLC following thiolysis and n-butanol/HCl hydrolysis, respectively. As expected, the results revealed marked differences of the ethyl acetate extracts, aqueous acetone extracts, and insoluble residues with regard to contents and mean degrees of polymerization of procyanidins. Total phenolic contents in the defatted apple seed residues ranged between 18.4 and 99.8 mg/g. Phloridzin was the most abundant phenolic compound, representing 79-92% of monomeric polyphenols. Yields of phenolic compounds significantly differed among the cultivars under study, with seeds of cider apples generally being richer in phloridzin and catechins than seeds of dessert apple cultivars. This is the first study presenting comprehensive data on the contents of phenolic compounds in apple seeds comprising extractable and nonextractable procyanidins. Furthermore, the present work points out a strategy for the sustainable and complete exploitation of apple seeds as valuable agro-industrial byproducts, in particular as a rich source of phloridzin and antioxidant flavanols.     

Physicochemical and Enzyme Characterization of Small and Large Starch Granules Isolated from Two Maize Cultivars

In this study, some morphological, physicochemical, and the initial characterization of the starch granule enzymes of blue and white maizes of small and large granules are described. Starch was isolated from blue and white maizes, and the small and large granules were separated. The efficiency of separation was higher in large granules than small of the blue maize starch. The amylose content was slightly greater (1.3%) in large granules than smaller in both starches studied. No differences in the average gelatinization temperature were found between large and small granules, but the enthalpy of gelatinization value was higher in the small granules. The electrophoretic pattern showed that the granule‐bound starch synthase (GBSSI) had higher expression in large than small granules and that explain the higher amylose content in the former granules. The differences showed in the starch biosynthesis enzymes in small and large granules might explain partially the physicochemical and functional properties of maize.