Antibacterial and antioxidant activities of essential oils isolated from Thymbra capitata L. (Cav.) andOriganum vulgare L

Antilisterial activities of Thymbra capitata and Origanum vulgare essential oils were tested against 41 strains of Listeria monocytogenes. The oil of T. capitata was mainly constituted by one component, carvacrol (79%), whereas for O. vulgare three components constituted 70% of the oil, namely, thymol (33%), gamma-terpinene (26%), and p-cymene (11%). T. capitata essential oil had a significantly higher antilisterial activity in comparison to O. vulgare oil and chloramphenicol. No significant differences in L. monocytogenes susceptibilities to the essential oils tested were registered. The minimum inhibitory concentration values of T. capitata essential oil and of carvacrol were quite similar, ranging between 0.05 and 0.2 microL/mL. Antioxidant activity was also tested, the essential oil of T. capitata showing significantly higher antioxidant activity than that of O. vulgare. Use of T. capitata and O. vulgare essential oils can constitute a powerful tool in the control of L. monocytogenes in food and other industries.     

Effects of road transportation or droving on the weight and metabolism of young bulls

This study evaluated the effects of the mode of transportation on weight and metabolism of young bulls, which are generally transported by two systems: droving and truck. This experiment consisted of two phases: transportation and refeeding and involved transportation by droving and truck. Fifty young Nellore bulls were separated in equal numbers in both groups, droving group and truck group. In the transportation phase, animals were moved, in a 640-km journey. The refeeding phase consisted of 84 days and commenced after the animals arrived at the fattening farm. The effect of the transportation system on animals’ weight, metabolic hormones, and serum biochemistry was assessed after 28, 56, and 84 days. During the transportation phase, animals in the droving group lost 10.11 kg and animals in the truck group gained 13.1 kg. The truck group showed 20.5 kg of weight gain at the end of the refeeding phase. The highest triiodothyronine (T₃) and thyroxine (T₄) concentrations were observed on days 0 and 60 in the transportation phase in both droving and truck groups. The serum cortisol concentration was higher in the droving group than in the truck group on day 56 of the refeeding phase. The IGF-I concentrations were higher during the refeeding phase in the droving group than in the truck group. Our results showed that transportation by droving leads to increased weight loss and reduced further weight gain compared to transportation by truck and that serum concentrations of T₄, cortisol, and insulin-like growth factor (IGF-I) hormones are altered by the transportation system.     

Ion levels in the gastrointestinal tract content and plasma of four teleosts with different feeding habits

The levels of various ions (Na⁺, Cl⁻, Ca²⁺, Mg²⁺, K⁺) in the fluid phase of the gastrointestinal contents and of the plasma were determined in four teleosts with different feeding habits: traira (Hoplias malabaricus), hassar (Hoplosternum littorale), silver catfish (Rhamdia quelen), and grass carp (Ctenopharyngodon idella). The results showed that most ionic levels in the fluid phase of the gastrointestinal tract seem to be affected by feeding habit and that these levels can be different from those found in the plasma. In practical terms, these results suggest that ionic levels of the gastrointestinal contents should be considered when preparing solutions for studies of intestinal absorption in fishes.     

Selective control of polyamide dyeing with acid dyes using hydroxypropyl-β-cyclodextrin

The effect of hydroxypropyl-β-cyclodextrin (HPβCD) in the dyeing of polyamide fabric was investigated under conditions that mimic industrial dyebaths where dye mixtures are used. The dyes used were Telon Red BN, Telon Yellow A-2R, and Telon Blue RR. The blue dye complexed with HPβCD whereas the other dyes did not do so under the conditions used. The dyeing results were compared with those obtained using a traditional retarding agent, Albegal B. The exhaustion dyeing data showed that HPβCD mainly affected the dyeing behavior of the blue dye that became encapsulated. In the case of the yellow and red dyes, changes in the overall kinetics of dyeing were observed, resulting in modified exhaustion profiles. In comparison, Albegal B retarded the blue dyeing process and increased the rate of exhaustion of the yellow dye while the exhaustion curve of red dye remained unchanged. The color uniformity of the dyed polyamide was improved when HPβCD was used. This resulted from the more controlled exhaustion rate during the critical phase of the dyeing process.     

Purification and characterization of an N-acetylglucosamine-binding lectin from Koelreuteria paniculata seeds and its effect on the larval development of Callosobruchus maculatus (Coleoptera: Bruchidae) and Anagasta kuehniella (Lepidoptera: Pyralidae)

This study describes the purification of an N-acetylglucosamine-binding lectin from Koelreuteria paniculata seeds and its effects on the larval development of Callobruchus maculatus and Anagasta kuehniella. The lectin (KpLec) was characterized and isolated by gel filtration, affinity column, and reverse phase chromatography. SDS-PAGE indicated that this lectin is a dimer composed of subunits of 22 and 44 kDa. The N terminus exhibited 40% similarity with Urtiga dioica agglutinin. KpLec was tested for anti-insect activity against C. maculatus and A. kuehniella. With regard to C. maculatus, an artificial diet containing 0.7 and 1% KpLec produced LD(50) and ED(50) value, respectively. However, for A. kuenhiella, an artificial diet containing 0.65% KpLec produced an LD(50), whereas 0.2% KpLec produced an ED(50). The transformation of genes coding for this lectin could be useful in the development of insect resistance in important agricultural crops.     

Root growth conditions in the topsoil as affected by tillage intensity

Many studies have reported impeded root growth in topsoil under reduced tillage or direct drilling, but few have quantified the effects on the least limiting water range for root growth. This study explored the effects of tillage intensity on critical soil physical conditions for root growth in the topsoil. Samples were taken from a 7-year tillage experiment on a Danish sandy loam at Foulum, Denmark (56°30′ N, 9°35′ E) in 2008. The main crop was spring barley followed by either dyer's woad (Isatis tinctoria L.) or fodder radish (Raphanus sativus L.) cover crops as subtreatment. The tillage treatments were direct drilling (D), harrowing 8-10 cm (H), and ploughing (P) to 20 cm depth. A chisel coulter drill was used in the H and D treatments and a traditional seed drill in the P treatment. Undisturbed soil cores were collected in November 2008 at soil field moisture capacity from the 4-8 and 12-16 cm depths.We estimated the critical aeration limit from either 10% air-filled porosity (ε_a) or relative gas diffusivity (D/D₀) of 0.005 or 0.02 and found a difference between the two methods. The critical limit of soil aeration was best assessed by measuring gas diffusivity directly. Root growth was limited by a high penetration resistance in the D and H soils (below tillage depth). Poor soil aeration did not appear to be a significant limiting factor for root growth for this sandy loam soil, irrespective of tillage treatment. The soil had a high macroporosity and D/D₀ exceeded 0.02 at field capacity. Fodder radish resulted in more macropores, higher gas diffusivity and lower pore tortuosity compared to dyer's woad. This was especially important for the H treatment where compaction was a significant problem at the lower depths of the arable layer (10-20 cm depth). Our results suggest that fodder radish could be a promising tool in the amelioration of soil compaction.     

Near infrared spectroscopy as a tool for intensive mapping of vineyards soil

The wine industry has always been particularly interested in the influence of the terroir characteristics on the features of a wine. Over the past few years, a growing interest has spurred on the mechanisms by which a particular soil influences the vine’s growth, grape variety characteristics and ultimately wine quality. Near-infrared spectroscopy (NIRS) is a rapid, non-destructive, low-cost and robust analytical method for chemical and physical property determination. Its use for soil characterization, discrimination and compound determination is rapidly increasing. In this work, NIRS data were collected in two vineyards, one in the Dão Wine Region (centre of Portugal) and one in the Vinhos Verdes Wine Region (North of Portugal) previously characterized in terms of soils. Wet, dried and dried-ground soil samples collected from specific vineyard locations were scanned on a Fourier-transform near infrared spectrometer (FTLA 2000, ABB, Quebec, Canada) in diffuse reflectance mode. Spectra were analysed with chemometric tools, namely principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). Results revealed that dried, ground soil samples gave better results, but not substantially so when compared with wet or dried samples. Discriminant models showed that the NIRS method is able to discriminate the different vineyard soil types, reproducing very accurately the mapping generated by pedology methods. Variations within the same soil type (present at different locations in the vineyard) were also detected by NIRS. The NIRS technology was shown to be suitable for correlating, complementing and perhaps eventually replacing costly, time-consuming vineyard soil mapping methods.