Nondestructive evaluation of anthocyanins in olive (Olea europaea) fruits by in situ chlorophyll fluorescence spectroscopy

Anthocyanins (Anths) in olive (Olea europaea L.) fruits at different degrees of pigmentation were assessed nondestructively by measuring chlorophyll fluorescence (ChlF). The method is based on the comparison of the ChlF excitation spectra from olives with different pigmentation from green to green-red, reddish-purple, and purple. The logarithm of the ratio between the fluorescence excitation spectra (logFER) from two different colored zones gave the difference in the absorption spectrum between them. The absorbance spectrum derived from the logFER between a red olive and the same olive devoid of the skin showed the typical Anth green band (at 550 nm). It matched that recorded by microspectrophotometry on a single pulp cell and the in vitro absorbance spectrum of the olive skin extract. As expected, the in vivo Anths absorption maximum increased in intensity going from less to more mature olives and was higher in the sun-exposed olive side with respect to the sun-shaded side. Absolute quantitative nondestructive determination of Anths for each olive sample was obtained by the logFER calculated for two excitation wavelengths, 550 and 625 nm, of ChlF at 740 nm. Going from green to purple skin colors, the Log[ChlF(625)/ChlF(550)] was fairly well-correlated to the extract Anths concentration. Finally, the relationship between the Anths and the other main phenolics present in the olives analyzed by high-performance liquid chromatography was evaluated. The main result was a net increase of verbascoside with increasing Anths content. On the basis of our results, the development of a new rapid and noninvasive method for the monitoring of olive development and ripening can be envisaged.     

Effects of dietary protein content on renal parameters in normal cats

This study evaluates the effect of dietary protein content on renal parameters in 23 healthy spayed female cats. The objective was to determine if cats eating diets high in protein will have higher serum urea nitrogen (UN) and creatinine values without a detectable change in kidney function, as assessed by urinalysis. A single random cross-over design was used. Cats were fed a standard maintenance diet for at least 1 month prior to the dietary trial. They were fed in two phases. For the first phase, cats were randomly assigned to receive either a high protein [HP=46% metabolizable energy (ME)] or low protein (LP=26% ME) diet. For the second phase, cats were fed whichever diet they were not fed during the phase I period. Blood and urine samples were collected at 2-week intervals for the duration of the study (10 weeks). UN, albumin, alanine aminotransferase and urine specific gravity were significantly higher, and creatinine and phosphorus were significantly lower (P<0.05) when cats were fed the HP diet as compared to when they were fed the LP diet, although none of the mean values were found to be outside of the corresponding reference interval. Dietary intake can result in clinically significant changes in UN and statistically significantly changes in several other biochemical analytes, although all analytes are likely to remain within normal reference intervals. Therefore, an accurate dietary history is necessary to help determine if renal parameters are being influenced by diet in a particular patient.     

Gastroduodenoscopy in the dog and cat.

Endoscopic examination of the upper gastrointestinal (GI) tract in dogs and cats is a relatively recent development. It was just over 20 years ago, in 1978, that the first series report of GI endoscopy in dogs and cats was presented. In those initial days, endoscopy was truly a novelty, and the primary uses for endoscopes were to retrieve foreign objects or visualize the esophagus and stomach. It was not until the mid-1980s that technology and training made gastroduodenoscopy standard practice. The evolution in endoscopic technology has also mirrored the evolution in computers and imaging modalities. The original fiberoptic endoscopes, although still available, are giving way to video endoscopy and digital imaging capabilities that provide spectacular images and an ability to generate hard copy images for medical records, teaching purposes, and research data that was previously not possible.     

Relationship between soil CO2 concentrations and forest-floor CO2 effluxes

To better understand the biotic and abiotic factors that control soil CO₂ efflux, we compared seasonal and diurnal variations in simultaneously measured forest-floor CO₂ effluxes and soil CO₂ concentration profiles in a 54-year-old Douglas fir forest on the east coast of Vancouver Island. We used small solid-state infrared CO₂ sensors for long-term continuous real-time measurement of CO₂ concentrations at different depths, and measured half-hourly soil CO₂ effluxes with an automated non-steady-state chamber. We describe a simple steady-state method to measure CO₂ diffusivity in undisturbed soil cores. The method accounts for the CO₂ production in the soil and uses an analytical solution to the diffusion equation. The diffusivity was related to air-filled porosity by a power law function, which was independent of soil depth. CO₂ concentration at all depths increased with increase in soil temperature, likely due to a rise in CO₂ production, and with increase in soil water content due to decreased diffusivity or increased CO₂ production or both. It also increased with soil depth reaching almost 10 mmol mol⁻¹ at the 50-cm depth. Annually, soil CO₂ efflux was best described by an exponential function of soil temperature at the 5-cm depth, with the reference efflux at 10 °C (F₁₀) of 2.6 μmol m⁻² s⁻¹ and the Q₁₀ of 3.7. No evidence of displacement of CO₂-rich soil air with rain was observed.Effluxes calculated from soil CO₂ concentration gradients near the surface closely agreed with the measured effluxes. Calculations indicated that more than 75% of the soil CO₂ efflux originated in the top 20 cm soil. Calculated CO₂ production varied with soil temperature, soil water content and season, and when scaled to 10 °C also showed some diurnal variation. Soil CO₂ efflux and concentrations as well as soil temperature at the 5-cm depth varied in phase. Changes in CO₂ storage in the 0–50 cm soil layer were an order of magnitude smaller than measured effluxes. Soil CO₂ efflux was proportional to CO₂ concentration at the 50-cm depth with the slope determined by soil water content, which was consistent with a simple steady-state analytical model of diffusive transport of CO₂ in the soil. The latter proved successful in calculating effluxes during 2004.     

Utilization of Marine Waste to Obtain β-Chitin Nanofibers and Films from Giant Humboldt Squid Dosidicus gigas

β-chitin was isolated from marine waste, giant Humboldt squid Dosidicus gigas, and further converted to nanofibers by use of a collider machine under acidic conditions (pH 3). The FTIR, TGA, and NMR analysis confirmed the efficient extraction of β-chitin. The SEM, TEM, and XRD characterization results verified that β-chitin crystalline structure were maintained after mechanical treatment. The mean particle size of β-chitin nanofibers was in the range between 10 and 15 nm, according to the TEM analysis. In addition, the β-chitin nanofibers were converted into films by the simple solvent-casting and drying process at 60 °C. The obtained films had high lightness, which was evidenced by the CIELAB color test. Moreover, the films showed the medium swelling degree (250–290%) in aqueous solutions of different pH and good mechanical resistance in the range between 4 and 17 MPa, depending on film thickness. The results obtained in this work show that marine waste can be efficiently converted to biomaterial by use of mild extractive conditions and simple mechanical treatment, offering great potential for the future development of sustainable multifunctional materials for various industrial applications such as food packaging, agriculture, and/or wound dressing.     

Changes in a knitted fabric’s surface properties due to enzyme treatments

Enzyme treatment technologies in textile processing have become commonly-applied techniques for the modification of fabric-handle appearance, and other surface and mechanical characteristics of fabrics. Most studies have focused on understanding the impact of enzyme treatments on the fabric preparation, dyeing, and finishing processes of woven fabrics, whilst only limited research has been reported regarding any enzymatic effects on the surface and handproperties of knitted fabrics. The aim of this study was to analyze the effects of two different enzymes Trichoderma reesei whole cellulase, and enriched (EGIII) endoglucanase cellulase, at three different enzyme dosages on 100 % cotton interlock knitted fabric. This was in order to evaluate certain surface properties such as pilling, friction. and geometrical roughness. Furthermore, the compression and tactile properties of knitted fabric were also analyzed. The results show that treatment conditions with enzyme Trichoderma reesei whole cellulase had the more pronounced effect on the surface properties compared to the enriched EGIII enzymes. In general, it can be concluded that both types of enzymes improved the surface properties and hand when compared with the silicone softener-treated reference sample of interlock knitted fabric, as is statistically confirmed by one-way analysis of variance.     

Uranium in the Groundwater of Permo-Triassic Aquifers of the Visok Region, Stara Planina, Eastern Serbia

An elevated concentration of uranium in the water of some springs in the Permo-Triassic sedimentary rocks of the Visok region, south-eastern slopes of the Stara Planina, eastern Serbia, is interpreted based on geological, hydrogeological and hydrochemical data. Uranium concentration in groundwater was first examined whilst exploring for uranium minerals as an energy resource. The purpose of a later hydrogeological investigation was assessment of a safe drinking water supply to a planned ski-centre hotel. The maximum contaminant level for uranium, recommended by the World Health Organization (WHO), is 15 μg/L. This work reviews and interprets the naturally elevated uranium in springs from the Permo-Triassic sediments of Visok, focusing on geological, hydrogeological, hydrogeochemical and other factors of uranium contamination. Uranium distribution in groundwater from Permo-Triassic aquifers was studied by taking groundwater, spring sediment and rock samples. The varied mobility of uranium depends largely on lithology, which also controls the chemistry of groundwater. The investigation results have shown that sulfate–calcium groundwater is a suitable facilitator of uranium mobility with a high migration coefficient of 0.77. Uranium concentrations in this water were up to 41 μg/L, with a Sa/Sr mass ratio of around 20, and a mineral content of about 0.5 g/L. The hydrochemistry was characteristically transitional Eh and pH neutral. Elevated uranium in groundwater has been reported globally and may be compared.     

In vitro antioxidant activity of ragweed (Ambrosia artemisiifolia L., Asteraceae) herb

The antioxidant activity in 70% aqueous acetone extracts of the herb of Ambrosia artemisiifolia L., Asteraceae was evaluated with regards to total polyphenol and flavonoid contents. Antioxidant activity has been assessed by two commonly used in vitro tests, based on determination of ferric-reducing antioxidant power (FRAP assay) and DPPH free radical scavenging ability (DPPH assay), against butylated hydroxytoluene (BHT), ascorbic acid and quercetin, which were used as positive control substances. The results of both antioxidant tests showed that the plant material expressed a considerable activity (DPPH IC₅₀ = 27.6 μg/ml; FRAP value = 2.37 mmol Fe²⁺/g), attributed to both flavonoid aglyca and resembling glycosides, as verified by dot-blot TLC analysis.     

Immobilization of cell wall invertase modified with glutaraldehyde for continuous production of invert sugar

Yeast cell wall invertase (CWI) was modified with dimethyl suberimidate, glutaraldehyde, formaldehyde, and sodium periodate. Retained activity after modification was 45% for CWI modified with formaldehyde, 77% for CWI modified with sodium periodate, 80% for CWI modified with glutaraldehyde, and 115% for CWI modified with dimethyl suberimidate. Chemically modified and native CWIs showed significantly broad pH stability (pH 3-11), whereas after incubations at 50, 60, and 70 °C, CWI modified with glutaraldehyde showed the highest thermostability. Optimum pH for CWI modified with glutaraldehyde was between 4 and 5, whereas optimum temperature was at 60 °C. Comparison to CWI modified with glutaraldehyde after immobilization within alginate beads showed broader pH optimum (4.0-5.5) as well as broader temperature optimum (55-70 °C). Column bed reactor packed with the immobilized CWI modified with glutaraldehyde was successfully used for the 95% inversion of 60% (w/w) sucrose at the flow rate of 3 bed volumes per hour, pH 4.9, and 45 °C. A 1 month productivity of 3844 kg of inverted sugar/kg of the immobilisate was obtained.