Assessment of the production of antioxidants from winemaking waste solids

Winemaking waste solids (WS, resulting from red grapes after fermentation and distillation to recover spirits) were subjected to various processing schemes for isolating fractions with antioxidant activity. The liquors entrapped in WS as received were separated by pressing and freeze-dried to yield a fraction with antioxidant activity (measured as DPPH radical scavenging capacity) comparable to those of synthetic antioxidants. A second approach based on the direct processing of raw WS in sulfuric acid medium under fixed operational conditions and further extraction of hydrolysis liquors with ethyl acetate enabled the isolation of a fraction with higher antioxidant ability at an improved yield. The most favorable approach started with a washing stage leading to liquors (which were directly freeze-dried to yield 1.20 g of extract/100 g of oven-dry WS and presented an EC50 of 0.41 g of extract/L) and washed solids, which were dried and subjected to hydrolytic processing (i) with water as a reactive in an autocatalyzed reaction (autohydrolysis) or (ii) with sulfuric acid solutions to give an ethyl acetate-soluble fraction with improved antioxidant properties (EC50 in the range of 0.18-0.40 g/L). Samples from washing liquors and processing of washed solids in aqueous medium were subjected to chromatographic fractionation and analysis to give isolates with remarkable antioxidant activity (with EC50 as low as 0.07 g/L) and to identify their major components.     

Echocardiographic and electrocardiographic examination of clinically healthy, conscious ferrets

Objectives : To assess the feasibility of performing electrocardiography (ECG) and echocardiography on conscious ferrets and to establish reference values for this species under these conditions. Methods : End‐systolic and end‐diastolic left ventricular (LV) diameters, LV and interventricular septal thicknesses were measured by M‐mode echocardiography, while left atrial, aortic and pulmonary trunk diameters were determined by two‐dimensional echocardiography in 46 ferrets. In some animals the maximum velocities of blood flow in the aorta and the pulmonary trunk were also measured by spectral Doppler. ECG examinations were performed by using limb leads both in right lateral recumbency and in the so‐called “hanging” position. In the course of the ECG examinations (n=43), the occurrences, directions, durations and amplitudes of the P, QRS and T waves and the duration of the PR‐ and QT intervals were recorded for all six leads. Results : ECG and echocardiography were successfully performed on non‐sedated ferrets in 90 and 96% of the cases, respectively. Males were significantly heavier and had larger cardiac dimensions compared to females. Clinical Significance : Performance of both echocardiography and ECG are feasible techniques in conscious ferrets, and reference values are now available for future comparisons.     

Preparation and promotion of fruit growth in kiwifruit of fluorinated N-phenyl-N'-1,2,3-thiadiazol-5-yl ureas

Seventeen phenyl-fluorinated analogues of thidiazuron [N-phenyl-N'-(1,2,3-thiadiazol-5-yl)urea, TDZ] have been prepared and characterized. The effects of each fluorinated urea on growth and quality of kiwifruits (Actinidia deliciosa) were evaluated by comparison with untreated (control) and TDZ-treated fruits. The results obtained showed a clear dependence of the growth-promoting activity of these fluorinated ureas on the pattern and degree of fluorine substitution in the phenyl ring. The most effective for promoting fruit growth was N-(2,3,5,6-tetrafluorophenyl)-N'-(1',2',3'-thiadiazol-5'-yl)urea at 25 ppm (at harvest, treated fruits were 58% heavier than untreated ones) followed by N-(3,5-difluorophenyl)-N'-(1',2',3'-thiadiazol-5'-yl)urea at 10 ppm (50%). Comparatively, TDZ-treated fruits were 31% (10 ppm) and 38% (25 ppm) heavier than untreated ones. The results also indicate that the effects of the more active phenyl-fluorinated ureas on some standard quality parameters of fruits, for example, percent of fruit dry matter content, soluble solids contents, total titratable acids, shape, and internal structure, are similar to those of TDZ. Quantitative structure-activity relationships have been derived for the fruit growth promoting activity of the phenyl-fluorinated analogues of TDZ.     

Determination of tetracycline antibiotic residues in edible swine tissues by liquid chromatography with spectrofluorometric detection and confirmation by mass spectrometry

A sensitive and specific method is described for the simultaneous determination of oxytetracycline, tetracycline (TC), and chlortetracycline residues in edible swine tissues, by combining liquid chromatography with spectrofluorometric and mass spectrometry detection. The procedure involved a preliminary extraction with EDTA-McIlvaine buffer acidified at pH 4.0, followed by solid-phase extraction cleanup using a polymeric sorbent. The liquid chromatography analysis was performed with spectrofluorometric detection after postcolumn derivatization with magnesium ions. The limits of quantification were 50 microg/kg for muscle and 100 microg/kg for kidney tissues. The recovery values were greater than 77.8% for muscle and 65.1% for kidney. The method has been successfully used for the quantification of tetracyclines in swine tissues samples. The selective liquid chromatography mass spectrometric analysis for confirmation of oxytetracycline in one positive swine muscle sample was made by atmospheric pressure chemical ionization (APCI). The APCI mass spectra of the TCs gave the protonated molecular ion and two typical fragment ions, required for their confirmation in single ion monitoring scan mode in animal tissues.     

Grape-seed procyanidins act as antiinflammatory agents in endotoxin-stimulated RAW 264.7 macrophages by inhibiting NFkB signaling pathway

Procyanindin extract (PE) is a mixture of polyphenols, mainly procyanidins, obtained from grape seed with putative antiinflammatory activity. We evaluated the PE effect on RAW 264.7 macrophages stimulated with lipopolysaccharide plus interferon-gamma that show a rapid enhanced production of prostaglandin E2 (PGE2) and nitric oxide (NO). Our results demonstrated that PE significantly inhibited the overproduction of NO, dose and time dependently. PE caused a marked inhibition of PGE2 synthesis when administered during activation. Moreover, PE pretreatment diminished iNOS mRNA and protein amount dose dependently (10-65 microg/mL). PE (65 microg/mL) pretreatment inhibited NFkappaB (p65) translocation to nucleus by nearly 40%. Trimeric and longer oligomeric-rich procyanidin fractions from PE (5-30 microg/mL) inhibited iNOS expression but not the monomeric forms catechin and epicatechin. Thus, we show that the degree of polymerization is important in determining procyanidin effects. PE was considerably a more effective inhibitor of NO biosynthesis (IC50 = 50 microg/mL) in comparison to other antiinflammatories, such as aspirin (3 mM), indomethacin (20 microM), and dexamethasone (9 nM). In conclusion, PE modulates inflammatory response in activated macrophages by the inhibition of NO and PGE2 production, suppression of iNOS expression, and NFkB translocation. These results demonstrate an immunomodulatory role of grape seed procyanidins and thus a potential health-benefit in inflammatory conditions that exert an overproduction of NO and PGE2.     

Antioxidant activity of olive pulp and olive oil phenolic compounds of the arbequina cultivar

The aim of this study was to characterize antioxidant activities of phenolic compounds that appear in olive pulp and olive oils using both radical scavenging and antioxidant activity tests. Antiradical and antioxidant activities of olive pulp and olive oil phenolic compounds were due mainly to the presence of a 3,4-dihydroxy moiety linked to an aromatic ring, and the effect depended on the polarity of the phenolic compound. Glucosides and more complex phenolics exhibited higher antioxidant activities toward oxidation of liposomes, whereas in bulk lipids aglycons were more potent antioxidants with the exception of oleuropein. Lignans acted as antioxidants only in liposomes, which could partly be due to their chelating activity, because liposome oxidation was initiated by cupric acetate. The antioxidant activity of virgin olive oil is principally due to the dialdehydic form of elenolic acid linked to hydroxytyrosol (3,4-DHPEA-EDA), a secoiridoid derivative (peak RT 36, structure unidentified), and luteolin.     

Antigens from Rhipicephalus sanguineus ticks elicit potent cell-mediated immune responses in resistant but not in susceptible animals

In the present study we compared the immunological reactions between Rhipicephalus sanguineus tick-infested susceptible (dogs and mice) and tick-resistant hosts (guinea pigs), elucidating some of the components of efficient protective responses against ticks. We found that T-cells from guinea pigs infested with adult ticks proliferate vigorously in the presence of concanavalin A (ConA), whereas ConA-induced cell proliferation of tick-infested mice and dogs was significantly decreased at 43.1 and 94.0%, respectively, compared to non-infested controls. Moreover, cells from mice and dogs submitted to one or three successive infestations did not exhibit a T-cell proliferative response to tick antigens, whilst cells from thrice tick-infested guinea pigs, when cultured with either a tick extract or tick saliva, displayed a significant increase in cell proliferation. Also, we evaluated the response of tick-infested mice to a cutaneous hypersensitivity test induced by a tick extract. Tick-infested mice developed a significant immediate reaction, whereby a 29.9% increase in the footpad thickness was observed. No delayed-type hypersensitivity (DTH) reaction was detected. Finally, the differential cell count at the tick attachment site in repeatedly infested mice exhibited a 6.6- and 4.1-fold increase in the percentage of eosinophils and neutrophils, respectively, compared to non-infested animals, while a decrease of 77.0-40.9 in the percentage of mononuclear cells was observed. The results of the cutaneous hypersensitivity test and the cellular counts at the tick feeding site for mice support the view that tick-infested mice develop an immune response to R. sanguineus ticks very similar to dogs, the natural host of this species of tick, but very different from guinea pigs (resistant host), which develop a DTH reaction in addition to a basophil and mononuclear cell infiltration at the tick-attachment site. In conclusion, saliva introduced during tick infestations reduces the ability of a susceptible animal host to respond to tick antigens that could stimulate a protective immune response. As a consequence, the animals present a lack of DTH response and disturbed cellular migration to tick feeding site, which can represent a deficient response against ticks.     

Hydroxymethanesulphinate salts and related decomposition products in wastewater

Hydroxymethanesulphinate (HMS) and its decomposition products such as HCHO, Zn and sulphites can be determined quantitatively in each other's presence by a polarographic method. In the alkaline medium it is possible to have well defined and separated waves relative to the oxidation of HMS ion and to the reduction of HCHO and zincate ion. The quantitative determination of these compounds is carried out with standard addition methods since the concentration-current relationship is linear. The SO₂ is determined in HClO₄ 0.1 M and in the same sample it is possible to determine even HMS, HCHO and Zn after addition of NaOH up to 0.1 M. Moreover, a method of indirect determination of HMS is herein described. This is based on the determination of HCHO released by means of a weak oxidation of HMS which is stoichiometrically proportional to the total HMS. The method is sensitive and is made specific for such types of wastewater which come from textile industries.